Science.gov

Sample records for abundant tick species

  1. Species diversity and abundance of ticks in three habitats in southern Italy.

    PubMed

    Dantas-Torres, Filipe; Otranto, Domenico

    2013-04-01

    A 2-year study was conducted from March 2010 to March 2012 in a forested area in southern Italy to evaluate the species diversity and abundance of free-living ticks in 3 different habitats: (i) a meadow habitat within an enclosure inhabited by roe deer (Capreolus capreolus); (ii) a man-made trail located in a high-altitude, forested area; and (iii) a grassland near a house inhabited by 3 people. In total, 10,795 ticks were collected. Ixodes ricinus was the most abundant species (69.0%), followed by Haemaphysalis inermis (19.1%), Rhipicephalus turanicus (6.7%), Dermacentor marginatus (3.2%), and Hyalomma marginatum (1.0%). The least frequently collected species were Rhipicephalus bursa, Haemaphysalis parva, Haemaphysalis sulcata, and Haemaphysalis concinna, representing together less than 1% of the collections. Immature ticks predominated over adult ticks. In particular, immature stages of Ix. ricinus (i.e., 3246 larvae and 3554 nymphs) represented 63% of the total number of ticks collected. High levels of species diversity and abundance of ticks were recorded in all habitats and the daily number of ticks collected was negatively correlated with daily mean temperature, evapotranspiration, and saturation deficit. This study indicates that the southern Italian climate is suitable for different tick species, which may find a preferred 'climate niche' during a specific season, when a combination of factors (e.g., suitable meteorological and environmental conditions) associated with the presence of suitable hosts will facilitate their development and reproduction.

  2. Ticks and tick-borne pathogens in South Bohemia (Czech Republic)--Spatial variability in Ixodes ricinus abundance, Borrelia burgdorferi and tick-borne encephalitis virus prevalence.

    PubMed

    Hönig, V; Svec, P; Halas, P; Vavruskova, Z; Tykalova, H; Kilian, P; Vetiskova, V; Dornakova, V; Sterbova, J; Simonova, Z; Erhart, J; Sterba, J; Golovchenko, M; Rudenko, N; Grubhoffer, L

    2015-07-01

    Spatial distribution of Ixodes ricinus tick host-seeking activity, as well as prevalence of Borrelia burgdorferi sensu lato and tick-borne encephalitis virus (TBEV) were studied in the TBE endemic area of South Bohemia (Czech Republic). High variability in tick abundance detected in a network of 30 study sites was most closely associated with characteristics of vegetation cover. Of 11,182 tested tick samples, 12% carried DNA of spirochete from B. burgdorferi s.l. complex. B. afzelii and B. garinii prevailed among spirochete species. The presence of B. spielmanii in the region was confirmed. The median number of borrelial genome copies in positive samples reached 6.6 × 10(3) by real-time PCR. The total prevalence of TBEV in pooled samples reached 0.32% (20,057 samples tested), at least one TBEV positive tick was present in 21 out of 30 sampling sites.

  3. Tick Paralysis

    MedlinePlus

    ... Resources Contact About The Foundation Select Page Tick Paralysis Menu What is Tick Paralysis? Where is Tick ... Tick Paralysis Tick-borne Relapsing Fever Tularemia Tick Paralysis Tick species that cause Tick Paralysis: Deer tick, ...

  4. [The species composition of mosquitoes and ticks in Armenia].

    PubMed

    Manukian, D V; Oganesian, A S; Shakhnazarian, S A; Aleksanian, Iu T

    2006-01-01

    Comprehensive epidemiological, entomological, virological, and parasitological studies were conducted to examine the species composition and size of bloodsucking arthropoda (mosquitoes and ticks). A total of 64,567 mosquitoes and 45,180 Ixodes ticks were collected. Among the mosquitoes, Anopheles maculipennis was a prevalent species (81.6%). In all climatic zones, Dermacentor marginatus was the largest in number and most abundant during flag collections from cattle and plants (62.5% and 95.5%, respectively). Virological studies of the collected field material identified 125 strains of arboviruses belonging to 10 viruses: Tyaginya, Sindbis, Batai, Dkhori, tick-borne encephalitis, West Nile fever, Tamdy, KGL, Geta, and Bkhandzha. The identified arboviruses are environmentally associated with both mosquitoes and ticks. The larger number and diversity of bloodsucking artropoda present a potential risk of outbursts of arbovirus infections on the territory of the republic.

  5. Altitudinal patterns of tick and host abundance: a potential role for climate change in regulating tick-borne diseases?

    PubMed

    Gilbert, Lucy

    2010-01-01

    The impact of climate change on vector-borne infectious diseases is currently controversial. In Europe the primary arthropod vectors of zoonotic diseases are ticks, which transmit Borrelia burgdorferi sensu lato (the agent of Lyme disease), tick-borne encephalitis virus and louping ill virus between humans, livestock and wildlife. Ixodes ricinus ticks and reported tick-borne disease cases are currently increasing in the UK. Theories for this include climate change and increasing host abundance. This study aimed to test how I. ricinus tick abundance might be influenced by climate change in Scotland by using altitudinal gradients as a proxy, while also taking into account the effects of hosts, vegetation and weather effects. It was predicted that tick abundance would be higher at lower altitudes (i.e. warmer climates) and increase with host abundance. Surveys were conducted on nine hills in Scotland, all of open moorland habitat. Tick abundance was positively associated with deer abundance, but even after taking this into account, there was a strong negative association of ticks with altitude. This was probably a real climate effect, with temperature (and humidity, i.e. saturation deficit) most likely playing an important role. It could be inferred that ticks may become more abundant at higher altitudes in response to climate warming. This has potential implications for pathogen prevalence such as louping ill virus if tick numbers increase at elevations where competent transmission hosts (red grouse Lagopus lagopus scoticus and mountain hares Lepus timidus) occur in higher numbers.

  6. Tick species and tick-borne infections identified in population from a rural area of Spain.

    PubMed Central

    Merino, Francisco Jesús; Nebreda, Teresa; Serrano, Jose Luis; Fernández-Soto, Pedro; Encinas, Antonio; Pérez-Sánchez, Ricardo

    2005-01-01

    To determine the tick species that bite humans in the province of Soria (Spain) and ascertain the tick-borne pathogens that threaten people's health in that province, 185 tick specimens were collected from 179 patients who sought medical advice at health-care centres. The ticks were identified, and their DNA examined by PCR for pathogens. Most ticks were collected in autumn and spring (59 and 57 respectively). Nine species of ticks were identified, the most frequent being Dermacentor marginatus (55.7%), Ixodes ricinus (12.4%) and Rhipicephalus bursa (11.9%). Ninety-seven females, 66 males, 21 nymphs and one larva were identified. Twenty-six ticks carried DNA from Rickettsia spp. (11 Rickettsia slovaca, 6 Rickettsia spp. RpA4/DnS14, 1 Rickettsia massiliae/Bar29, and 8 unidentified); two ticks carried DNA from Borrelia burgdorferi sensu lato and seven ticks harboured DNA from Anaplasma phagocytophilum. PMID:16181517

  7. Ticks

    USGS Publications Warehouse

    Ginsberg, H.S.; Faulde, M.K.

    2008-01-01

    The most common vector-borne diseases in both Europe and North America are transmitted by ticks. Lyme borreliosis (LB), a tick-borne bacterial zoonosis, is the most highly prevalent. Other important tick-borne diseases include TBE (tick-borne encephalitis) and Crimean-Congo haemorrhagic fever in Europe, Rocky Mountain spotted fever (RMSF) in North America, and numerous less common tick-borne bacterial, viral, and protozoan diseases on both continents. The major etiological agent of LB is Borrelia burgdorferi in North America, while in Europe several related species of Borrelia can also cause human illness. These Borrelia genospecies differ in clinical manifestations, ecology (for example, some have primarily avian and others primarily mammalian reservoirs), and transmission cycles, so the epizootiology of LB is more complex in Europe than in North America. Ticks dwell predominantly in woodlands and meadows, and in association with animal hosts, with only limited colonization of human dwellings by a few species. Therefore, suburbanization has contributed substantially to the increase in tick-borne disease transmission in North America by fostering increased exposure of humans to tick habitat. The current trend toward suburbanization in Europe could potentially result in similar increases in transmission of tick-borne diseases. Incidence of tick-borne diseases can be lowered by active public education campaigns, targeted at the times and places of greatest potential for encounter between humans and infected ticks. Similarly, vaccines (e.g., against TBE) are most effective when made available to people at greatest risk, and for high-prevalence diseases such as LB. Consultation with vector-borne disease experts during the planning stages of new human developments can minimize the potential for residents to encounter infected ticks (e.g., by appropriate dwelling and landscape design). Furthermore, research on tick vectors, pathogens, transmission ecology, and on

  8. Decreased small mammal and on-host tick abundance in association with invasive red imported fire ants (Solenopsis invicta).

    PubMed

    Castellanos, Adrian A; Medeiros, Matthew C I; Hamer, Gabriel L; Morrow, Michael E; Eubanks, Micky D; Teel, Pete D; Hamer, Sarah A; Light, Jessica E

    2016-09-01

    Invasive species may impact pathogen transmission by altering the distributions and interactions among native vertebrate reservoir hosts and arthropod vectors. Here, we examined the direct and indirect effects of the red imported fire ant (Solenopsis invicta) on the native tick, small mammal and pathogen community in southeast Texas. Using a replicated large-scale field manipulation study, we show that small mammals were more abundant on treatment plots where S. invicta populations were experimentally reduced. Our analysis of ticks on small mammal hosts demonstrated a threefold increase in the ticks caught per unit effort on treatment relative to control plots, and elevated tick loads (a 27-fold increase) on one common rodent species. We detected only one known human pathogen (Rickettsia parkeri), present in 1.4% of larvae and 6.7% of nymph on-host Amblyomma maculatum samples but with no significant difference between treatment and control plots. Given that host and vector population dynamics are key drivers of pathogen transmission, the reduced small mammal and tick abundance associated with S. invicta may alter pathogen transmission dynamics over broader spatial scales.

  9. Decreased small mammal and on-host tick abundance in association with invasive red imported fire ants (Solenopsis invicta)

    PubMed Central

    Medeiros, Matthew C. I.; Hamer, Gabriel L.; Morrow, Michael E.; Eubanks, Micky D.; Teel, Pete D.

    2016-01-01

    Invasive species may impact pathogen transmission by altering the distributions and interactions among native vertebrate reservoir hosts and arthropod vectors. Here, we examined the direct and indirect effects of the red imported fire ant (Solenopsis invicta) on the native tick, small mammal and pathogen community in southeast Texas. Using a replicated large-scale field manipulation study, we show that small mammals were more abundant on treatment plots where S. invicta populations were experimentally reduced. Our analysis of ticks on small mammal hosts demonstrated a threefold increase in the ticks caught per unit effort on treatment relative to control plots, and elevated tick loads (a 27-fold increase) on one common rodent species. We detected only one known human pathogen (Rickettsia parkeri), present in 1.4% of larvae and 6.7% of nymph on-host Amblyomma maculatum samples but with no significant difference between treatment and control plots. Given that host and vector population dynamics are key drivers of pathogen transmission, the reduced small mammal and tick abundance associated with S. invicta may alter pathogen transmission dynamics over broader spatial scales. PMID:27651533

  10. Landscape level variation in tick abundance relative to seasonal migration in red deer.

    PubMed

    Qviller, Lars; Risnes-Olsen, Nina; Bærum, Kim Magnus; Meisingset, Erling L; Loe, Leif Egil; Ytrehus, Bjørnar; Viljugrein, Hildegunn; Mysterud, Atle

    2013-01-01

    Partial migration is common among northern ungulates, typically involving an altitudinal movement for seasonally migratory individuals. The main driving force behind migration is the benefit of an extended period of access to newly emerged, high quality forage along the green up gradient with increasing altitude; termed the forage maturation hypothesis. Any other limiting factor spatially correlated with this gradient may provide extra benefits or costs to migration, without necessarily being the cause of it. A common ectoparasite on cervids in Europe is the sheep tick (Ixodes ricinus), but it has not been tested whether migration may lead to the spatial separation from these parasites and thus potentially provide an additional benefit to migration. Further, if there is questing of ticks in winter ranges in May before spring migration, deer migration may also play a role for the distribution of ticks. We quantified the abundance of questing sheep tick within winter and summer home ranges of migratory (n=42) and resident red deer (Cervus elaphus) individuals (n=32) in two populations in May and August 2009-2012. Consistent with predictions, there was markedly lower abundance of questing ticks in the summer areas of migrating red deer (0.6/20 m(2)), both when compared to the annual home range of resident deer (4.9/20 m(2)) and the winter home ranges of migrants (5.8/20 m(2)). The reduced abundances within summer home ranges of migrants were explained by lower abundance of ticks with increasing altitude and distance from the coast. The lower abundance of ticks in summer home ranges of migratory deer does not imply that ticks are the main driver of migration (being most likely the benefits expected from forage maturation), but it suggests that ticks may add to the value of migration in some ecosystems and that it may act to spread ticks long distances in the landscape.

  11. Species, developmental stage and infection with microbial pathogens of engorged ticks removed from dogs and questing ticks.

    PubMed

    Leschnik, M W; Khanakah, G; Duscher, G; Wille-Piazzai, W; Hörweg, C; Joachim, A; Stanek, G

    2012-12-01

    Research into tick-borne diseases implies vector sampling and the detection and identification of microbial pathogens. Ticks were collected simultaneously from dogs that had been exposed to tick bites and by flagging the ground in the area in which the dogs had been exposed. In total, 200 ticks were sampled, of which 104 came from dogs and 96 were collected by flagging. These ticks were subsequently examined for DNA of Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, Rickettsia spp. and Babesia canis. A mixed sample of adult ticks and nymphs of Ixodes ricinus (Ixodida: Ixodidae) and Haemaphysalis concinna (Ixodida: Ixodidae) was obtained by flagging. Female I. ricinus and adult Dermacentor reticulatus (Ixodida: Ixodidae) ticks dominated the engorged ticks removed from dogs. Rickettsia spp. were detected in 17.0% of the examined ticks, A. phagocytophilum in 3.5%, B. canis in 1.5%, and B. burgdorferi s.l. in 16.0%. Ticks with multiple infections were found only among the flagging sample. The ticks removed from the dogs included 22 infected ticks, whereas the flagging sample included 44 infected ticks. The results showed that the method for collecting ticks influences the species composition of the sample and enables the detection of a different pattern of pathogens. Sampling strategies should be taken into consideration when interpreting studies on tick-borne pathogens.

  12. Abundance estimation of Ixodes ticks (Acari: Ixodidae) on roe deer (Capreolus capreolus).

    PubMed

    Kiffner, Christian; Lödige, Christina; Alings, Matthias; Vor, Torsten; Rühe, Ferdinand

    2010-09-01

    Despite the importance of roe deer as a host for Ixodes ticks in central Europe, estimates of total tick burden on roe deer are not available to date. We aimed at providing (1) estimates of life stage and sex specific (larvae, nymphs, males and females, hereafter referred to as tick life stages) total Ixodes burden and (2) equations which can be used to predict the total life stage burden by counting the life stage on a selected body area. Within a period of 1(1/2) years, we conducted whole body counts of ticks from 80 hunter-killed roe deer originating from a beech dominated forest area in central Germany. Averaged over the entire study period (winter 2007-summer 2009), the mean tick burden per roe deer was 64.5 (SE +/- 10.6). Nymphs were the most numerous tick life stage per roe deer (23.9 +/- 3.2), followed by females (21.4 +/- 3.5), larvae (10.8 +/- 4.2) and males (8.4 +/- 1.5). The individual tick burden was highly aggregated (k = 0.46); levels of aggregation were highest in larvae (k = 0.08), followed by males (k = 0.40), females (k = 0.49) and nymphs (k = 0.71). To predict total life stage specific burdens based on counts on selected body parts, we provide linear equations. For estimating larvae abundance on the entire roe deer, counts can be restricted to the front legs. Tick counts restricted to the head are sufficient to estimate total nymph burden and counts on the neck are appropriate for estimating adult ticks (females and males). In order to estimate the combined tick burden, tick counts on the head can be used for extrapolation. The presented linear models are highly significant and explain 84.1, 77.3, 90.5, 91.3, and 65.3% (adjusted R (2)) of the observed variance, respectively. Thus, these models offer a robust basis for rapid tick abundance assessment. This can be useful for studies aiming at estimating effects of abiotic and biotic factors on tick abundance, modelling tick population dynamics, modelling tick-borne pathogen transmission dynamics

  13. A list of the 70 species of Australian ticks; diagnostic guides to and species accounts of Ixodes holocyclus (paralysis tick), Ixodes cornuatus (southern paralysis tick) and Rhipicephalus australis (Australian cattle tick); and consideration of the place of Australia in the evolution of ticks with comments on four controversial ideas.

    PubMed

    Barker, Stephen C; Walker, Alan R; Campelo, Dayana

    2014-10-15

    Seventy species of ticks are known from Australia: 14 soft ticks (family Argasidae) and 56 hard ticks (family Ixodidae). Sixteen of the 70 ticks in Australia may feed on humans and domestic animals (Barker and Walker 2014). The other 54 species of ticks in Australia feed only on wild mammals, reptiles and birds. At least 12 of the species of ticks in Australian also occur in Papua New Guinea. We use an image-matching system much like the image-matching systems of field guides to birds and flowers to identify Ixodes holocyclus (paralysis tick), Ixodes cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). Our species accounts have reviews of the literature on I. holocyclus (paralysis tick) from the first paper on the biology of an Australian tick by Bancroft (1884), on paralysis of dogs by I. holocyclus, to papers published recently, and of I. cornuatus (southern paralysis tick) and Rhipicephalus (Boophilus) australis (Australian cattle tick). We comment on four controversial questions in the evolutionary biology of ticks: (i) were labyrinthodont amphibians in Australia in the Devonian the first hosts of soft, hard and nuttalliellid ticks?; (ii) are the nuttalliellid ticks the sister-group to the hard ticks or the soft ticks?; (iii) is Nuttalliella namaqua the missing link between the soft and hard ticks?; and (iv) the evidence for a lineage of large bodied parasitiform mites (ticks plus the holothyrid mites plus the opiliocarid mites).

  14. Ticks of Australia. The species that infest domestic animals and humans.

    PubMed

    Barker, Stephen C; Walker, Alan R

    2014-06-18

    The book Australian Ticks by F.H.S. Roberts (1970) is a land-mark in Australian tick biology. But it is time for a new and improved book on the ticks of Australia. The present book has identification guides and accounts of the biology and diseases associated with the 16 species of ticks that may feed on domestic animals and humans in Australia. These comprise five argasid (soft) ticks: Argas persicus (poultry tick), Argas robertsi (Robert's bird tick), Ornithodoros capensis (seabird soft tick), O. gurneyi (kangaroo soft tick), Otobius megnini (spinose ear tick); and 11 ixodid (hard) ticks, Amblyomma triguttatum (ornate kangaroo tick), Bothriocroton auruginans (wombat tick), B. hydrosauri (southern reptile tick), Haemaphysalis bancrofti (wallaby tick), H. longicornis (bush tick), Ixodes cornuatus (southern paralysis tick), I. hirsti (Hirst's marsupial tick), I. holocyclus (paralysis tick), I. tasmani (common marsupial tick), Rhipicephalus (Boophilus) australis (Australian cattle tick) and R. sanguineus (brown dog tick).  We use an image-matching system to identify ticks, much like the image-matching systems used in field-guides for birds and flowers. Ticks may be identified by drawings that emphasise unique matrices of uniformly defined morphological characters that, together, allow these 16 ticks to be identified by morphology unequivocally. The species accounts have seven sections: (i) General; (ii)  Differential diagnosis; (iii) Hosts; (iv) Life-cycle and seasonality; (v) Disease; (vi) Habitat and geographic distribution; (vii) Genes and genomes; and (viii) Other information. There are 71 figures and tables, including a glossary character matrices, drawings of life-cycles, drawings of genera, species, and colour photographs of tick biology.

  15. Survey of ticks collected in Mississippi for Rickettsia, Ehrlichia, and Borrelia species.

    PubMed

    Goddard, Jerome; Sumner, John W; Nicholson, William L; Paddock, Christopher D; Shen, John; Piesman, Joseph

    2003-12-01

    From November 1999 through October 2000, we tested ticks collected from vegetation as well as from deer, dogs, and humans for spotted fever group (SFG) rickettsiae, Ehrlichia chaffeensis, and Borrelia spp. spirochetes. A total of 149 adult ticks representing four species was collected from 11 collection sites from southwestern to northern Mississippi. Amblyomma americanum was most commonly collected (n=68), followed by Ixodes scapularis (n=53). The bird tick, Ixodes brunneus (usually rare), was the third most commonly collected tick (n=17). Eleven Dermacentor variabilis were also collected. Ticks were cut longitudinally to make smears on three microscope slides. The remaining body parts were frozen at -65 degrees C for additional testing. Tick smears were stained by direct immunofluorescence assays (DFA) for Rickettsia spp. and Borrelia spp., while indirect immunofluorescence assays (IFA) were used for Ehrlichia spp. The corresponding tick for each positive smear was evaluated using PCR analysis. None of the 149 ticks tested was DFA positive for Borrelia spp. However, smears of 30 (20%) and 32 (22%) ticks reacted with anti-E. chaffeensis sera and anti-R. rickettsii conjugate (known to react with several members of the spotted fever group), respectively. None of the ticks staining with the IFA for Ehrlichia was positive for E. chaffeensis using PCR. However, 23 (72%) of 32 FA-positive ticks for SFG rickettsiae yielded amplicons of the appropriate size when tested using a PCR assay for SFG rickettsiae, corresponding to an overall infection rate with SFG rickettsiae among the collected ticks of 15%. Smears of 12 (71%) of 17 I. brunneus revealed abundant bacilliform bacteria. PCR amplification of DNA from a single I. brunneus containing these bacteria was performed using universal primers for the 16S rRNA gene as well as Borrelia-specific primers. The predominant sequence obtained using the universal primers did not match any sequence in GenBank, but it showed 91

  16. New Borrelia species detected in ixodid ticks in Oromia, Ethiopia.

    PubMed

    Kumsa, Bersissa; Socolovschi, Cristina; Raoult, Didier; Parola, Philippe

    2015-04-01

    Little is known about Borrelia species transmitted by hard ticks in Ethiopia. The present study was conducted from November 2011 through March 2014 to address the occurrence and molecular identity of these bacteria in ixodid ticks infesting domestic animals in Oromia, Ethiopia. A total of 767 ixodid ticks collected from domestic animals were screened for Borrelia DNA by quantitative (q) real-time PCR followed by standard PCR and sequencing to identify the species. Overall, 3.8% (29/767) of the tested ticks were positive for Borrelia DNA, including 8/119 (6.7%) Amblyomma cohaerens, 1/42 (2.4%) Am. gemma, 3/53 (5.7%) Am. variegatum, 5/22 (22.7%) Amblyomma larvae, 3/60 (5%) Amblyomma nymphs, 2/139 (1.4%) Rhipicephalus (Boophilus) decoloratus, 2/31 (6.4%) Rh. decoloratus nymphs, and 5/118 (4.2%) Rh. pulchellus using 16S genus-specific qPCR. The prevalence of Borrelia DNA was significantly higher in genus Amblyomma (20/298, 6.7%) than in the genus Rhipicephalus (9/417, 2.1%) ticks (P=0.001). Sequencing of PCR products from the flaB and 16S rRNA genes of Borrelia spp. from Amblyomma ticks showed the presence of a new species between the relapsing fever and Lyme disease groups. However, Borrelia sp. detected in Rhipicephalus ticks clustered with B. theileri/B. lonestari. The human pathogenicity of the Borrelia sp. detected in Amblyomma ticks from Ethiopia has not yet been investigated, whereas the Borrelia sp. detected in Rhipicephalus ticks in our study is the causative agent of bovine borreliosis in cattle and may have veterinary importance in different parts of Ethiopia. Furthermore, the detection of previously unrecognized Borrelia species in Amblyomma and Rhipicephalus ticks in Ethiopia generates additional questions concerning the bacterial fauna in hard ticks and will prompt researchers to perform detailed studies for better understanding of ixodid ticks associated bacteria.

  17. Assessing the abundance, seasonal questing activity, and Borrelia and tick-borne encephalitis virus (TBEV) prevalence of Ixodes ricinus ticks in a Lyme borreliosis endemic area in Southwest Finland.

    PubMed

    Sormunen, Jani J; Klemola, Tero; Vesterinen, Eero J; Vuorinen, Ilppo; Hytönen, Jukka; Hänninen, Jari; Ruohomäki, Kai; Sääksjärvi, Ilari E; Tonteri, Elina; Penttinen, Ritva

    2016-02-01

    Studies have revealed that Ixodes ricinus (Acari: Ixodidae) have become more abundant and their geographical distribution extended northwards in some Nordic countries during the past few decades. However, ecological data of tick populations in Finland are sparse. In the current study, I. ricinus abundance, seasonal questing activity, and their Borrelia spp. and tick-borne encephalitis virus (TBEV) prevalence were evaluated in a Lyme borreliosis endemic area in Southwest Finland, Seili Island, where a previous study mapping tick densities was conducted 12 years earlier. A total of 1940 ticks were collected from five different biotopes by cloth dragging during May-September 2012. The overall tick density observed was 5.2 ticks/100m(2) for nymphs and adults. Seasonal questing activity of ticks differed between biotopes and life stages: bimodal occurrences were observed especially for nymphal and adult ticks in forested biotopes, while larvae in pastures exhibited mostly unimodal occurrence. Prevalence of Borrelia and TBEV in ticks was evaluated using conventional and real-time PCR. All samples were negative for TBEV. Borrelia prevalence was 25.0% for adults (n=44) and the minimum infection rate (MIR) 5.6% for pooled nymph samples (191 samples, 1-14 individuals per sample; 30/191 positive). No Borrelia were detected in pooled larval samples (63 samples, 1-139 individuals per sample). Five species of Borrelia were identified from the samples: B. afzelii, B. burgdorferi s.s., B. garinii, B. valaisiana and B. miyamotoi. In Finland, B. valaisiana and B. miyamotoi have previously been reported from the Åland Islands but not from the mainland or inner archipelago. The results of the present study suggest an increase in I. ricinus abundance on the island.

  18. Ixodid ticks of road-killed wildlife species in southern Italy: new tick-host associations and locality records.

    PubMed

    Lorusso, Vincenzo; Lia, Riccardo Paolo; Dantas-Torres, Filipe; Mallia, Egidio; Ravagnan, Silvia; Capelli, Gioia; Otranto, Domenico

    2011-11-01

    The present study aimed to identify ticks collected from road-killed wildlife species retrieved in several localities of southern Italy and to assess the presence of Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum and Rickettsia spp. DNA in ticks. Collections were carried out from January 2000 to December 2009 on wild animals found dead within the territories of 11 municipalities from three regions (i.e., Apulia, Basilicata, and Calabria). In total, 189 carcasses of wild animals belonging to 10 species were checked for tick infestation, and 40 animals belonging to seven species were found parasitized. One hundred and twenty-five ixodid ticks (11 larvae, 14 nymphs, 77 males, and 23 females) were collected and identified as belonging to nine species, namely Dermacentor marginatus, Haemaphysalis erinacei, Hyalomma marginatum, Ixodes acuminatus, Ixodes canisuga, Ixodes hexagonus, Ixodes ricinus, Rhipicephalus bursa, and Rhipicephalus turanicus. None of the 36 tick specimens tested by PCR was positive for tick-borne pathogens. The results add new information on the tick fauna associated with wild animals in Italy, reporting new tick-host associations. Further field studies are still needed to ascertain the suitability of certain wildlife species as hosts for some tick species, particularly for those implicated in the transmission of pathogens to domestic animals and humans. Finally, from a conservation perspective, it would be interesting to assess whether these wild animals (e.g., Lepus corsicanus) are exposed to tick-borne pathogens, investigating the possible implications for their health and behavior.

  19. Prevalence and genotypes of Anaplasma species and habitat suitability for ticks in a Mediterranean ecosystem.

    PubMed

    Torina, Alessandra; Alongi, Angelina; Naranjo, Victoria; Estrada-Peña, Agustín; Vicente, Joaquín; Scimeca, Salvatore; Marino, Anna M F; Salina, Felice; Caracappa, Santo; de la Fuente, José

    2008-12-01

    Anaplasma species are tick-transmitted pathogens that impact veterinary and human health. Sicily is one of the locations where these pathogens are endemic. Sicily represents a typical Mediterranean ecosystem to study Anaplasma infection and tick habitat suitability. The aims of this study were (i) to characterize by 16S rRNA and species-specific msp4 gene PCR the prevalence and genotypes of A. marginale, A. phagocytophilum, and A. ovis in the most abundant host species in Sicilian provinces and (ii) to correlate differences between hosts and between western and eastern Sicily with the habitat suitability for ticks in these regions. Differences were found in the prevalence of Anaplasma spp. between different hosts and between western and eastern provinces. The differences in Anaplasma prevalence between different hosts may be explained by pathogen host tropism. The differences between western and eastern provinces correlated with the tick habitat suitability in these regions. The analysis of Anaplasma genotypes suggested a higher host and regional specificity for A. phagocytophilum than for A. marginale and A. ovis strains, a finding probably associated with the broader host range of A. phagocytophilum. The presence of identical A. marginale genotypes in the two regions may reflect cattle movement. The results for A. ovis suggested the possibility of some genotypes being host specific. These results provide information potentially useful for the management of tick-borne diseases caused by Anaplasma spp. in Sicily and other Mediterranean regions and may contribute to the development of models to predict the risks for these tick-borne pathogens.

  20. Lone star tick abundance, fire, and bison grazing in tall-grass prairie

    USGS Publications Warehouse

    Cully, J.F.

    1999-01-01

    Lone star ticks (Amblyomma americanum L.) were collected by drag samples of 1 km transects on 12 watersheds at Konza Prairie Research Natural Area near Manhattan, Kans., during summer 1995-1996. Watersheds were treated to 2 experimental treatments: 3 burn intervals (1-year, 4-year, and 20-year) and 2 grazing treatments (grazed by bison (Bos bison L.) or ungrazed). The objectives were to determine whether fire interval, time since most recent burn, and the presence of large ungulate grazers would cause changes in lone star tick abundance in tallgrass prairie in central Kansas. Watersheds burned at 1-year intervals had fewer larvae and adults than watersheds burned at 4-year or 20-year intervals. Watersheds burned during the year of sampling had fewer ticks than watersheds burned one or more years in the past. For watersheds burned 1 or more years in the past there was no effect from time since burn. The presence of bison did not affect tick abundance. Spring burning is an effective method to reduce tick populations in tallgrass prairie during the year of the burn.

  1. Fencing and mowing as effective methods for reducing tick abundance on very small, infested plots.

    PubMed

    Del Fabbro, Simone

    2015-03-01

    The tick Ixodes ricinus (L.) transmits a large variety of pathogens to humans and is therefore a matter of concern for public health. Different strategies for reducing the risk of tick bite, and thus of infection, have been developed and vary according to the kind of exposure (occupational, recreational, peridomestic). The present study (carried out in an endemic region for both Lyme borreliosis and tick-borne encephalitis) aimed to assess the efficacy of two simple and cheap interventions for reducing I. ricinus abundance around residential properties surrounded by wooded areas. The immediate impact of exclosures (host-targeted control methods) and mowing (vegetation management) on very small surfaces (<1ha) were evaluated both alone and in combination. Results suggest that fencing (even if applied on very small surfaces), by preventing the entrance of tick reproductive hosts, can decrease the abundance of parasites in a short time, and that mowing can contribute to reach the goal. This control method could be of great value in small portions of heavily infested areas that have to be kept tick-free to reduce the risk of peridomestic exposure or to permit their recreational use (e.g. picnic areas within natural parks). Benefits appear even greater when considering that these interventions are environmental safe, cheap, technically simple and effective even in close proximity to heavy infested woodlands.

  2. Francisella species in ticks and animals, Iberian Peninsula.

    PubMed

    Lopes de Carvalho, I; Toledo, A; Carvalho, C L; Barandika, J F; Respicio-Kingry, L B; Garcia-Amil, C; García-Pérez, A L; Olmeda, A S; Zé-Zé, L; Petersen, J M; Anda, P; Núncio, M S; Escudero, R

    2016-02-01

    The presence of Francisella species in 2134 ticks, 93 lagomorphs and 280 small mammals from the Iberian Peninsula was studied. Overall, 19 ticks and 6 lagomorphs were positive for Francisella tularensis subsp. holarctica, suggesting, as described for other regions, that lagomorphs may have an important role in the maintenance of F. tularensis in nature. Of the 6 positive lagomorphs, 4 were identified as the European rabbit, Oryctogalus cuniculus. Additionally, 353 ticks and 3 small mammals were PCR positive for Francisella-like endosymbionts (FLEs) and one small mammal was also positive for Francisella hispaniensis-like DNA sequences. Among FLE positive specimens, a variety of sequence types were detected: ticks were associated with 5 lpnA sequence types, with only one type identified per tick, in contrast to 2 lpnA sequence types detected in a single wood mouse (Apodemus sylvaticus). To our knowledge, this is the first report of FLEs in free-living small mammals as well as the first detection of F. hispaniensis-like sequences in a natural setting.

  3. Species diversity and geographic distribution of hard ticks (Acari: Ixodoidea: Ixodidae) infesting domestic ruminants, in Qazvin Province, Iran.

    PubMed

    Shemshad, Khadijeh; Rafinejad, Javad; Kamali, Karim; Piazak, Norayer; Sedaghat, Mohammad Mahdi; Shemshad, Masoomeh; Biglarian, Akbar; Nourolahi, Fathollah; Valad Beigi, Enshallah; Enayati, Ahmad Ali

    2012-01-01

    This report presents the results of the first faunistic study of hard ticks in Qazvin province of Iran. The primary objective was to determine the species diversity and geographic distribution of hard ticks that parasitize domestic ruminants. Information about the abiotic preferences of these species has been provided. A total of 286 cattle, 1,053 goats, and 2,050 sheep were examined in 13 villages in 28 flocks distributed throughout the studied areas. Total direct body collections of ticks were made from each domestic ruminant. A total of 228 Ixodid specimens belonging to nine species in three different genera were recorded in the areas, including Boophilus annulatus (Say, 1821), Hyalomma anatolicum Koch, 1844, Hyalomma asiaticum (Schulze and Schlettke, 1929), Hyalomma detritum Schulze, 1919, Hyalomma dromedarii Koch, 1844, Hyalomma marginatum Koch 1844, Hyalomma schulzei Olenev, 1931, Rhipicephalus bursa Canestrini and Fanz, 1878 and Rhipicephalus sanguineus (Latreille, 1806). The most abundant species on sheep was R. sanguineus (46.92%), while B. annulatus (6.6%) found only on cattle. A finding of great significance was that R. sanguineus, the main vector of babesiosis, is firmly established throughout the counties. A further objective of the study was to compare the abundance of the major tick species on domestic ruminants. This was carried out at 19 sampling sites. The highest number of ticks was collected in July-August during the hot season.

  4. Seasonal dynamics of tick species in an urban park of Rome.

    PubMed

    Di Luca, Marco; Toma, Luciano; Bianchi, Riccardo; Quarchioni, Elisa; Marini, Luca; Mancini, Fabiola; Ciervo, Alessandra; Khoury, Cristina

    2013-12-01

    Regular collections were obtained in the Natural Reserve of the Insugherata of Rome during 2011 in order to obtain the tick species composition and the respective seasonal dynamics of the area. A total of 325 ticks was collected in selected sites by means of drag sampling. Among the identified species, Rhipicephalus turanicus was the most abundant (72.3%), followed by Ixodes ricinus (19.7%), Dermacentor marginatus (6.5%), Haemaphysalis punctata (1.2%), and Rhipicephalus bursa (0.3%). R. turanicus occurred mainly in pastures, showing a mono-modal seasonal activity pattern from spring to early summer. Questing I. ricinus were prevalent in woodland from October to May, and the seasonal trend of specimens showed a weak peak in winter. Although adult D. marginatus exhibited seasonal dynamics similar to I. ricinus, with an activity period from October to April, this species occurred in a different environment (pasture) and with considerably lower densities. Haemaphysalis punctata and R. bursa were rare, with an apparent autumn and autumn-winter seasonal activity, respectively. While the species diversity recorded appears as an unequivocal consequence of the natural state of the park, the remarkable R. turanicus density could be a direct effect of the recent introduction of wild boar, as carriers, from the close Veio Park. The presence of the species, a proven vector of various diseases in humans and domestic animals, is discussed in the light of the possible risk of tick-bite exposure of park workers and visitors.

  5. Molecular screening for Midichloria in hard and soft ticks reveals variable prevalence levels and bacterial loads in different tick species.

    PubMed

    Cafiso, Alessandra; Bazzocchi, Chiara; De Marco, Leone; Opara, Maxwell N; Sassera, Davide; Plantard, Olivier

    2016-10-01

    Candidatus Midichloria mitochondrii, symbiont of the sheep tick Ixodes ricinus, was the first described member of the family Candidatus Midichloriaceae, order Rickettsiales. Recent reports are expanding our view of this family, now including numerous bacteria of great biological and medical interest, indicating a widespread distribution with an increasing range of hosts, with ticks being strongly represented. Here we present a molecular screening of 17 tick species, detecting and quantifying bacteria of the family Midichloriaceae in seven of them, including the first report of a representative of this family in a soft tick species (Argasidae), Ornithodoros maritimus. Based on sequence identity and phylogenetic analysis we propose that all these bacterial symbionts of ticks could be members of the genus Midichloria. The performed screening highlights different prevalence levels and variable bacterial loads in different tick species including one, Ixodes aulacodi, where the bacterium is present in all examined individuals, like in I. ricinus. This result prompts us to hypothesize different roles of Midichloria bacteria in different tick species.

  6. Serotonin-like immunoreactivity in the central nervous system of two Ixodid tick species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Immunocytochemistry was used to detect the presence of serotonin-like immunoreactive (5HT-IR) neurons and neuronal processes in the central nervous system (CNS), the synganglion, of two Ixodid tick species; the winter tick, Dermacentor albipictus and the lone star tick, Amblyomma americanum. Seroto...

  7. Tick Bites

    MedlinePlus

    ... that go outdoors, you need to beware of ticks. Ticks are small bloodsucking parasites. Many species transmit diseases ... of the diseases you can get from a tick bite are Lyme disease, ehrlichiosis, Rocky Mountain spotted ...

  8. Seasonal variation in the abundance and distribution of ticks that parasitize Microcebus griseorufus at the Bezà Mahafaly Special Reserve, Madagascar

    PubMed Central

    Rodriguez, Idalia A.; Rasoazanabary, Emilienne; Godfrey, Laurie R.

    2015-01-01

    At Bezà Mahafaly Special Reserve (BMSR), Madagascar, mouse lemurs (Microcebus griseorufus) are parasitized by multiple species of haemaphysaline ticks. At present we know little about the role ticks play in wild lemur populations and how they can alter interspecies relationships within communities or impact host fitness. In order to better understand these dynamics at BMSR, we examined parasite-host interactions as well as the ecology of mouse lemurs and their infesting ticks, Haemaphysalis lemuris and H. sp. cf. simplex. We show that season, host sex, and habitat influence the relative abundance of ticks on mouse lemurs. Specifically, infestations occur only during the dry season (May–October), are higher in males, and are higher at the study site with the most ground cover and with greater density of large-bodied hosts. Microcebus likely experience decreased susceptibility to tick infestations during the wet season because at that time they rarely if ever descend to the ground. Similarly, male mouse lemurs have higher infestation rates than females because of the greater time they spend traveling and foraging on the ground. During the dry season, Microcebus likely serve as hosts for the tenrec tick, H. sp. cf. simplex, when tenrecs hibernate. In turn, during the wet season when mouse lemurs rarely descend to the ground, other small mammals at the reserve may serve as maintenance hosts for populations of immature ticks. The synchronous development of larvae and nymphs could present high risk for vector-borne disease in Microcebus. This study also provides a preliminary description of the ecology and life cycle of the most common lemur tick, H. lemuris. PMID:26767168

  9. Seasonal variation in the abundance and distribution of ticks that parasitize Microcebus griseorufus at the Bezà Mahafaly Special Reserve, Madagascar.

    PubMed

    Rodriguez, Idalia A; Rasoazanabary, Emilienne; Godfrey, Laurie R

    2015-12-01

    At Bezà Mahafaly Special Reserve (BMSR), Madagascar, mouse lemurs (Microcebus griseorufus) are parasitized by multiple species of haemaphysaline ticks. At present we know little about the role ticks play in wild lemur populations and how they can alter interspecies relationships within communities or impact host fitness. In order to better understand these dynamics at BMSR, we examined parasite-host interactions as well as the ecology of mouse lemurs and their infesting ticks, Haemaphysalis lemuris and H. sp. cf. simplex. We show that season, host sex, and habitat influence the relative abundance of ticks on mouse lemurs. Specifically, infestations occur only during the dry season (May-October), are higher in males, and are higher at the study site with the most ground cover and with greater density of large-bodied hosts. Microcebus likely experience decreased susceptibility to tick infestations during the wet season because at that time they rarely if ever descend to the ground. Similarly, male mouse lemurs have higher infestation rates than females because of the greater time they spend traveling and foraging on the ground. During the dry season, Microcebus likely serve as hosts for the tenrec tick, H. sp. cf. simplex, when tenrecs hibernate. In turn, during the wet season when mouse lemurs rarely descend to the ground, other small mammals at the reserve may serve as maintenance hosts for populations of immature ticks. The synchronous development of larvae and nymphs could present high risk for vector-borne disease in Microcebus. This study also provides a preliminary description of the ecology and life cycle of the most common lemur tick, H. lemuris.

  10. Species composition, distribution, and ecological preferences of the ticks of grazing sheep in north-central Spain.

    PubMed

    Estrada-Peña, A; Quíez, J; Sánchez Acedo, C

    2004-06-01

    The distribution and ecological preferences of tick (Acari: Ixodidae) parasites of grazing sheep in the region of Aragón (north-central Spain) were surveyed on flocks four times a year and mapped into a 5 x 5 km grid. Nine tick species were found. These were species of the Rhipicephalus sanguineus group (about 95% of them Rhipicephalus turanicus Pomerantsev, in 91% of cells of the grid), Rhipicephalus bursa Canestrini & Fanzago (79% of cells), Dermacentor marginatus (Sulzer) (58% of cells), Haemaphysalis punctata Canestrini & Fanzago (74% of cells) and Ixodes ricinus (Linnaeus) 14% of cells. Other species weakly represented in the surveys were Dermacentor reticulatus (Fabricius), Haemaphysalis sulcata Canestrini & Fanzago and Hyalomma m. marginatum Koch. Data on temperature, Normalized Difference Vegetation index (NDVI), topography, vegetation categories and plant productivity were used to build models of distribution and abundance of D. marginatus, H. punctata, R. bursa and R. turanicus. The occurrence models largely incorporated climatic variables and had good discrimination ability (P < 0.0001 for every modelled species, correct classification rate or sensitivity within 0.89 and 0.99), whereas the abundance models had a lower explanatory power. These models are relevant in the understanding of the variables composing the main distribution patterns, but they are unable adequately to predict the density. Abundance models produce good predictions in cells with low tick density, whereas poor correlation is observed in sites with high tick abundance. Several causes may be responsible for this low predictive power of the abundance models. Model output might be sensible to host density, to local farming practices, or to the size of the grid used to refer the results of the survey. In the latter case, small patches may support locally important populations of ticks, influencing largely the results of the survey. These patches of particular abiotic conditions, or

  11. Variation in the Microbiota of Ixodes Ticks with Regard to Geography, Species, and Sex

    PubMed Central

    Van Treuren, Will; Ponnusamy, Loganathan; Brinkerhoff, R. Jory; Gonzalez, Antonio; Parobek, Christian M.; Juliano, Jonathan J.; Andreadis, Theodore G.; Falco, Richard C.; Ziegler, Lorenza Beati; Hathaway, Nicholas; Keeler, Corinna; Emch, Michael; Bailey, Jeffrey A.; Roe, R. Michael; Apperson, Charles S.; Knight, Rob

    2015-01-01

    Ixodes scapularis is the principal vector of Lyme disease on the East Coast and in the upper Midwest regions of the United States, yet the tick is also present in the Southeast, where Lyme disease is absent or rare. A closely related species, I. affinis, also carries the pathogen in the South but does not seem to transmit it to humans. In order to better understand the geographic diversity of the tick, we analyzed the microbiota of 104 adult I. scapularis and 13 adult I. affinis ticks captured in 19 locations in South Carolina, North Carolina, Virginia, Connecticut, and New York. Initially, ticks from 4 sites were analyzed by 454 pyrosequencing. Subsequently, ticks from these sites plus 15 others were analyzed by sequencing with an Illumina MiSeq machine. By both analyses, the microbiomes of female ticks were significantly less diverse than those of male ticks. The dissimilarity between tick microbiomes increased with distance between sites, and the state in which a tick was collected could be inferred from its microbiota. The genus Rickettsia was prominent in all locations. Borrelia was also present in most locations and was present at especially high levels in one site in western Virginia. In contrast, members of the family Enterobacteriaceae were very common in North Carolina I. scapularis ticks but uncommon in I. scapularis ticks from other sites and in North Carolina I. affinis ticks. These data suggest substantial variations in the Ixodes microbiota in association with geography, species, and sex. PMID:26150449

  12. Variation in the Microbiota of Ixodes Ticks with Regard to Geography, Species, and Sex.

    PubMed

    Van Treuren, Will; Ponnusamy, Loganathan; Brinkerhoff, R Jory; Gonzalez, Antonio; Parobek, Christian M; Juliano, Jonathan J; Andreadis, Theodore G; Falco, Richard C; Ziegler, Lorenza Beati; Hathaway, Nicholas; Keeler, Corinna; Emch, Michael; Bailey, Jeffrey A; Roe, R Michael; Apperson, Charles S; Knight, Rob; Meshnick, Steven R

    2015-09-01

    Ixodes scapularis is the principal vector of Lyme disease on the East Coast and in the upper Midwest regions of the United States, yet the tick is also present in the Southeast, where Lyme disease is absent or rare. A closely related species, I. affinis, also carries the pathogen in the South but does not seem to transmit it to humans. In order to better understand the geographic diversity of the tick, we analyzed the microbiota of 104 adult I. scapularis and 13 adult I. affinis ticks captured in 19 locations in South Carolina, North Carolina, Virginia, Connecticut, and New York. Initially, ticks from 4 sites were analyzed by 454 pyrosequencing. Subsequently, ticks from these sites plus 15 others were analyzed by sequencing with an Illumina MiSeq machine. By both analyses, the microbiomes of female ticks were significantly less diverse than those of male ticks. The dissimilarity between tick microbiomes increased with distance between sites, and the state in which a tick was collected could be inferred from its microbiota. The genus Rickettsia was prominent in all locations. Borrelia was also present in most locations and was present at especially high levels in one site in western Virginia. In contrast, members of the family Enterobacteriaceae were very common in North Carolina I. scapularis ticks but uncommon in I. scapularis ticks from other sites and in North Carolina I. affinis ticks. These data suggest substantial variations in the Ixodes microbiota in association with geography, species, and sex.

  13. Relationship between temporal abundance of ticks and incidence of Lyme borreliosis in Lower Silesia regions of Poland.

    PubMed

    Kiewra, D; Zaleśny, G

    2013-12-01

    The aim of this study was to identify the factors determining the incidence of Lyme borreliosis (LB) in south-western Poland by estimating the prevalence of B. burgdorferi s. l. in I. ricinus, and to analyze the temporal abundance of ticks in relation to epidemiological data on LB incidence. Host-seeking ticks collected in 2011 in four districts in southwestern Poland were examined by nested PCR for the presence of B. burgdorferi s.l. In total, 2,507 host-seeking I. ricinus were collected. The temporal abundance of ticks varied between districts. The minimal infection rates with B. burgdorferi s.l. were 11.5% for nymphs and 37.7% for adults. There were no statistical differences in the level of infection between districts either for nymphs or for adults. Five different genospecies were identified within the B. burgdorferi s.l. complex: B. garinii, B. afzelii, B. lusitaniae, B. valasiana, and B. burgdorferi s.s., and additionally B. miyamotoi. Our results point to a relationship between tick temporal abundance and LB incidence both for adults and nymphs. The high abundance of ticks is positively correlated with the number of LB cases in humans. The tick's abundance may be considered as a major factor in determining the LB risk in southwestern Poland.

  14. Tick species, tick-borne pathogens and symbionts in an insular environment off the coast of Western France.

    PubMed

    Michelet, Lorraine; Joncour, Guy; Devillers, Elodie; Torina, Alessandra; Vayssier-Taussat, Muriel; Bonnet, Sarah I; Moutailler, Sara

    2016-10-01

    Insular environments provide ideal natural conditions to study disease ecology, especially emerging diseases, due to clear differentiation between local and long-distance transmission. Such environments are of particular interest regarding tick-borne pathogens (TBP), since animal exchange with the mainland (along with any ticks they carry) is limited, and because such locations could lie on migratory routes for birds carrying ticks. Therefore both tick species and TBP may display different prevalence than those observed on the continent. As such, an epidemiological survey was performed on Belle-Ile-en-Mer, an island off the coast of Western France, in order to estimate the prevalence of tick species and the microorganisms they carried. Three tick species, Dermacentor marginatus, D. reticulatus, and Haemaphysalis punctata were collected at five different sites in 2010 and 2011. All ticks were tested for pathogen's and symbiont's DNA by (i) PCR for Anaplasma spp., Borrelia spp., Rickettsia spp.; (ii) real-time PCR for Francisella tularensis, Francisella-like endosymbionts (FLE) and Coxiella spp. and (iii) PCR-RLB for Babesia-Theileria spp. Pathogen DNA detected in D. marginatus including Borrelia spp. (18%), Rickettsia spp. (13%) which was identified as R. slovaca, Babesia spp. (8%), and Theileria spp. (1%). Pathogens detected in D. reticulatus including Rickettsia spp. (31%) identified as R. raoulti, Francisella-like endosymbiont (86%), and Babesia spp (21%). Pathogens detected in H. punctata including Rickettsia spp. (1%) identified as R. aeschlimannii, FLE (0.4%), Babesia spp. (18%), and Theileria spp. (7%). Anaplasma spp., F. tularensis, or Coxiella spp. were not detected in any of the collected ticks. This study represents the first epidemiological survey of the insular Belle-Ile-en-Mer environment. It demonstrated the presence of expected pathogens, consistent with reports from island veterinarians or physicians, as well as unexpected pathogens, raising

  15. Clonal growth and plant species abundance

    PubMed Central

    Herben, Tomáš; Nováková, Zuzana; Klimešová, Jitka

    2014-01-01

    Background and Aims Both regional and local plant abundances are driven by species' dispersal capacities and their abilities to exploit new habitats and persist there. These processes are affected by clonal growth, which is difficult to evaluate and compare across large numbers of species. This study assessed the influence of clonal reproduction on local and regional abundances of a large set of species and compared the predictive power of morphologically defined traits of clonal growth with data on actual clonal growth from a botanical garden. The role of clonal growth was compared with the effects of seed reproduction, habitat requirements and growth, proxied both by LHS (leaf–height–seed) traits and by actual performance in the botanical garden. Methods Morphological parameters of clonal growth, actual clonal reproduction in the garden and LHS traits (leaf-specific area – height – seed mass) were used as predictors of species abundance, both regional (number of species records in the Czech Republic) and local (mean species cover in vegetation records) for 836 perennial herbaceous species. Species differences in habitat requirements were accounted for by classifying the dataset by habitat type and also by using Ellenberg indicator values as covariates. Key Results After habitat differences were accounted for, clonal growth parameters explained an important part of variation in species abundance, both at regional and at local levels. At both levels, both greater vegetative growth in cultivation and greater lateral expansion trait values were correlated with higher abundance. Seed reproduction had weaker effects, being positive at the regional level and negative at the local level. Conclusions Morphologically defined traits are predictive of species abundance, and it is concluded that simultaneous investigation of several such traits can help develop hypotheses on specific processes (e.g. avoidance of self-competition, support of offspring) potentially

  16. Species interactions in occurrence data for a community of tick-transmitted pathogens

    PubMed Central

    Estrada-Peña, Agustín; de la Fuente, José

    2016-01-01

    Interactions between tick species, their realized range of hosts, the pathogens they carry and transmit, and the geographic distribution of species in the Western Palearctic were determined based on evidence published between 1970–2014. These relationships were linked to remotely sensed features of temperature and vegetation and used to extract the network of interactions among the organisms. The resulting datasets focused on niche overlap among ticks and hosts, species interactions, and the fraction of the environmental niche in which tick-borne pathogens may circulate as a result of interactions and overlapping environmental traits. The resulting datasets provide a valuable resource for researchers interested in tick-borne pathogens, as they conciliate the abiotic and biotic sides of their niche, allowing exploration of the importance of each host species acting as a vertebrate reservoir in the circulation of tick-transmitted pathogens in the environmental niche. PMID:27479213

  17. Ectoparasites of Microtus californicus and Possible Emergence of an Exotic Ixodes Species Tick in California.

    PubMed

    Poulsen, Amanda; Conroy, Chris; Foley, Patrick; Ott-Conn, Caitlin; Roy, Austin; Brown, Richard; Foley, Janet

    2015-09-01

    California voles (Microtus californicus Peale) harbor fleas and ticks, may be infected with vector-borne pathogens, and could themselves suffer from disease and serve as a source of infection for people and other animals. Here we summarize publications, museum archives, and recent records of ticks and fleas from California voles. There have been 18 flea species reported on California voles with geographic locations reported for 13. During recent statewide surveys, we found six flea species, with the highest species richness in Humboldt County. We found three of five previously reported tick species as well as a tick resembling the eastern North American tick Ixodes minor Neumann (which we here designate Ixodes "Mojave morphotype") on isolated Amargosa voles and Owens Valley voles (Microtus californicus vallicola Bailey) in Inyo County in 2012 and 2014. Additional incidental observations of this Mojave morphotype tick were on a western harvest mouse (Reithrodontomys megalotis Baird) at the Mojave site and a montane vole (Microtus montanus Peale) in the Owens Valley, both in March, 2014. We cannot rule out that this tick species has been present in remote areas of California but gone unrecognized, but these data are consistent with recent introduction of this tick, possibly from migrating birds. Changes in the ectoparasite fauna suggest changing ecologies of vectors and vector-borne pathogens that could influence animals and people as well.

  18. The diversity and prevalence of hard ticks attacking human hosts in Eastern Siberia (Russian Federation) with first description of invasion of non-endemic tick species.

    PubMed

    Khasnatinov, Maxim Anatolyevich; Liapunov, Alexander Valeryevich; Manzarova, Ellina Lopsonovna; Kulakova, Nina Viktorovna; Petrova, Irina Viktorovna; Danchinova, Galina Anatolyevna

    2016-02-01

    Hard ticks are the vectors of many pathogens including tick-borne encephalitis virus and the Lyme disease agent Borrelia burgdorferi sensu lato. In Eastern Siberia, Ixodes persulcatus, Dermacentor nuttalli, Dermacentor silvarum and Haemaphysalis concinna are regarded as aggressive to humans. Recently, significant changes in world tick fauna have been reported and this affects the spread of tick-borne pathogens. We studied the current species diversity, population structure and prevalence of tick-borne pathogens of hard ticks (Acari: Ixodidae) that attacked humans in Eastern Siberia (Irkutsk region, Russia). In total, 31,892 individual ticks were identified and analysed during the years 2007-2014. The majority (85.4%) of victims was bitten by I. persulcatus, 14.55% of attacks on humans were caused by D. nuttalli and D. silvarum, whereas H. concinna was documented only in 15 cases (0.05%). The seasonal activity and the age/gender structure of the tick population were studied as well. Among all the studied ticks, three unconventional species, i.e. Rhipicephalus sanguineus, Dermacentor reticulatus and Amblyomma americanum, were identified. Analysis of tick bite histories indicates at least three events of invasion of non-endemic ticks into the ecosystems of northern Eurasia with harsh continental climates. Invading ticks are able to reach the adult life stage and are aggressive to the local human population. Phylogenetic analysis of mt 16S rRNA gene fragments suggests multiple independent routes of tick migration to Eastern Siberia. Possible implications to human health and epidemiology of tick-borne infections are discussed.

  19. Which forest bird species are the main hosts of the tick, Ixodes ricinus, the vector of Borrelia burgdorferi sensu lato, during the breeding season?

    PubMed

    Marsot, M; Henry, P-Y; Vourc'h, G; Gasqui, P; Ferquel, E; Laignel, J; Grysan, M; Chapuis, J-L

    2012-07-01

    Wild birds are important hosts for vector-borne pathogens, especially those borne by ticks. However, few studies have been conducted on the role of different bird species within a community as hosts of vector-borne pathogens. This study addressed individual and species factors that could explain the burden of Ixodes ricinus on forest birds during the reproductive periods of both vectors and hosts. The goal was to identify which bird species contribute the most to the tick population at the community level. Birds were mist-netted on four plots in 2008 and on seven plots in 2009 in two forests (Sénart and Notre Dame, near Paris, France). The dependence of the tick load per bird upon environmental conditions (questing nymph density, year and plot) and on host species traits (species, age, sex, body size, vertical space use, level of innate and acquired immunity) was analysed. Finally, the relative contribution of each bird species to the local dynamics of ticks was estimated, while accounting for their respective abundance. Tick burden differed markedly between bird species and varied according to questing nymph density. Bird species with a high body mass, those that forage low in the vegetation, and those that had a high innate immune response and a high spleen mass were more likely to have a high tick burden. Four species (the Common Blackbird, Turdus merula, the European Robin, Erithacus rubecula, the Song Thrush, Turdus philomelos, and the Winter Wren, Troglodytes troglodytes) hosted more than 90% of the ticks in the local bird community. These species, and particularly T. merula which was host to a high proportion of the nymphs, are likely to contribute significantly to the circulation of pathogens for which they are competent, such as the agent of Lyme borreliosis.

  20. Comparison of tick-borne microorganism communities in Ixodes spp. of the Ixodes ricinus species complex at distinct geographical regions.

    PubMed

    Movila, Alexandru; Dubinina, Helen V; Sitnicova, Natalia; Bespyatova, Liubov; Uspenskaia, Inga; Efremova, Galina; Toderas, Ion; Alekseev, Andrey N

    2014-05-01

    Characterizing the tick-borne microorganism communities of Ixodes ricinus (sheep tick) and Ixodes persulcatus (taiga tick) from the I. ricinus species complex in distinct geographical regions of Eastern Europe and European Russia, we demonstrated differences between the two ticks. Taiga ticks were more frequently mono- and co-infected than sheep ticks: 24.4 % (45/184 tested ticks) versus 17.5 % (52/297) and 4.3 % (8/184) versus 3.4 % (10/297), respectively. Ginsberg co-infection index values were significant at the various sites. Diversity of the tick-borne microorganism communities was estimated by the Shannon index, reaching values of 1.71 ± 0.46 and 1.20 ± 0.15 at the sheep-tick and the taiga-tick harbored sites, respectively. Richness of the tick-borne microorganism community in the sheep tick collection sites was about twice the value of the taiga tick collection sites. Future investigations are warranted to further characterize the peculiarities of the tick-borne microorganism communities among the ticks of the Ixodes ricinus complex.

  1. The relationship between deer density, tick abundance, and human cases of Lyme disease in a residential community.

    PubMed

    Kilpatrick, Howard J; LaBonte, Andrew M; Stafford, Kirby C

    2014-07-01

    White-tailed deer (Odocoileus virginianus Zimmerman), serve as the primary host for the adult blacklegged tick (Ixodes scapularis Say), the vector for Lyme disease, human babesiosis, and human granulocytic anaplasmosis. Our objective was to evaluate the degree of association between deer density, tick abundance, and human cases of Lyme disease in one Connecticut community over a 13-yr period. We surveyed 90-98% of all permanent residents in the community six times from 1995 to 2008 to document resident's exposure to tick-related disease and frequency and abundance of deer observations. After hunts were initiated, number and frequency of deer observations in the community were greatly reduced as were resident-reported cases of Lyme disease. Number of resident-reported cases of Lyme disease per 100 households was strongly correlated to deer density in the community. Reducing deer density to 5.1 deer per square kilometer resulted in a 76% reduction in tick abundance, 70% reduction in the entomological risk index, and 80% reduction in resident-reported cases of Lyme disease in the community from before to after a hunt was initiated.

  2. Insights into the development of Ixodes scapularis: a resource for research on a medically important tick species.

    PubMed

    Kocan, Katherine M; de la Fuente, José; Coburn, Lisa A

    2015-11-14

    Ticks (Acari: Ixodida) are arthropod ectoparasites dependent on a bloodmeal from a vertebrate host at each developmental stage for completion of their life cycle. This tick feeding cycle impacts animal health by causing damage to hides, secondary infections, immune reactions and diseases caused by transmission of pathogens. The genus Ixodes includes several medically important species that vector diseases, including granulocytic anaplasmosis and Lyme disease. I. scapularis, commonly called the black-legged or deer tick, is a medically-important tick species in North America and therefore was the first tick genome to be sequenced, thus serving as an important resource for tick research. This Primer focuses on the normal developmental cycle and laboratory rearing of I. scapularis. Definition of normal morphology, along with a consistent source of laboratory-reared I. scapularis, are fundamental for all aspects of future research, especially the effects of genetic manipulation and the evaluation of tick vaccine efficacy. Recent research important for the advancement of tick research, namely the development of tick cell culture systems for study of ticks and tick-borne pathogens, RNA interference for genetic manipulation of ticks and discovery of candidate antigens for development of tick vaccines, are briefly presented along with areas to target for future research.

  3. Wild birds and urban ecology of ticks and tick-borne pathogens, Chicago, Illinois, USA, 2005-2010.

    PubMed

    Hamer, Sarah A; Goldberg, Tony L; Kitron, Uriel D; Brawn, Jeffrey D; Anderson, Tavis K; Loss, Scott R; Walker, Edward D; Hamer, Gabriel L

    2012-10-01

    Bird-facilitated introduction of ticks and associated pathogens is postulated to promote invasion of tick-borne zoonotic diseases into urban areas. Results of a longitudinal study conducted in suburban Chicago, Illinois, USA, during 2005-2010 show that 1.6% of 6,180 wild birds captured in mist nets harbored ticks. Tick species in order of abundance were Haemaphysalis leporispalustris, Ixodes dentatus, and I. scapularis, but 2 neotropical tick species of the genus Amblyomma were sampled during the spring migration. I. scapularis ticks were absent at the beginning of the study but constituted the majority of ticks by study end and were found predominantly on birds captured in areas designated as urban green spaces. Of 120 ticks, 5 were infected with Borrelia burgdorferi, spanning 3 ribotypes, but none were infected with Anaplasma phagocytophilum. Results allow inferences about propagule pressure for introduction of tick-borne diseases and emphasize the large sample sizes required to estimate this pressure.

  4. Detection of a Borrelia species in questing Gulf Coast ticks, Amblyomma maculatum

    PubMed Central

    Lee, Jung Keun; Smith, Whitney Crow; McIntosh, Chelsea; Ferrari, Flavia Girao; Moore-Henderson, Brittany; Varela-Stokes, Andrea

    2015-01-01

    Borrelia spp. are agents of Lyme disease and relapsing fever, diseases which use Ixodes hard ticks and Ornithodoros soft ticks, respectively, as primary vectors. Some relapsing fever spirochetes, such as B. miyamotoi, are also found in hard ticks. To date, no Borrelia sp. is known to use the hard tick, Amblyomma maculatum, as a vector. However, both B. burgdorferi and B. lonestari were recently detected in A. maculatum removed from hosts. In our study, DNA extracts from 306 questing adult A. maculatum collected in Mississippi in 2009 and 2010 were tested for Borrelia spp. DNA by PCR amplification of flaB and 16S rRNA gene targets. An additional 97 A. maculatum collected in 2013 were tested by amplification of 16S rRNA gene target. Two ticks, one collected in 2009 and the other in 2010, were positive by PCR of the flaB and 16S rRNA gene targets; both were collected from the same location in central Mississippi. Interestingly, 16S rRNA gene amplicons from these two tick extracts were 98% identical to twelve Borrelia spp. including the reptile-associated spirochete B. turcica and Borrelia sp. “tAG158M”; flaB amplicons from these two ticks shared closest identity (89%) to the reptile-associated spirochete, B. turcica. These results demonstrate a Borrelia sp. in unfed A. maculatum ticks that is unique from other species in the NCBI database and in a clade with reptile-associated Borrelia species. Detection of a previously unrecognized Borrelia in a hard tick species generates additional questions regarding the bacterial fauna in these arthropods and warrants further studies to better understand this fauna. PMID:24844970

  5. Hepatozoon and Theileria species detected in ticks collected from mammals and snakes in Thailand.

    PubMed

    Sumrandee, Chalao; Baimai, Visut; Trinachartvanit, Wachareeporn; Ahantarig, Arunee

    2015-04-01

    We report the detection of Hepatozoon and Theileria in 103 ticks from mammals and snakes in Thailand. By using a genus-specific 18S rRNA PCR, Hepatozoon and Theileria spp. were detected in 8% and 18%, respectively, of ticks (n=79) removed from mammals. Of the ticks removed from snakes (n=24), 96% were infected with Hepatozoon spp., but none were infected with Theileria. Phylogenetic analysis revealed that Hepatozoon spp. detected from Dermacentor astrosignatus and Dermacentor auratus ticks from Wild boar (Sus scrofa) formed a phylogenetic group with many isolates of Hepatozoon felis that were distantly related to a species group containing Hepatozoon canis and Hepatozoon americanum. In contrast, a phylogenetic analysis of the Hepatozoon sequences of snake ticks revealed that Hepatozoon spp. from Amblyomma varanense from King cobra (Ophiophagus hannah) and Amblyomma helvolum ticks from Indochinese rat snake (Ptyas korros), and Asiatic water snake (Xenochrophis piscator) are grouped with Hepatozoon spp. recently isolated from Monocellate cobras, Reticulated pythons and Burmese pythons, all of Thai origin, and with Hepatozoon sp. 774c that has been detected from a tick species obtained from Argus monitors in Australia. A phylogenetic analysis demonstrated that Theileria spp. from Rhipicephalus (Boophilus) microplus, Haemaphysalis obesa, and Haemaphysalis lagrangei ticks from Sambar deer (Cervus unicolor) cluster with the Theileria cervi isolates WU11 and 239, and Theileria sp. Iwate 141. We report for the first time a Hepatozoon species that shares genetic similarity with Hepatozoon felis found in Dermacentor astrosignatus and Dermacentor auratus ticks collected from Wild boars in Thailand. In addition, we found the presence of a Theileria cervi-like sp. which suggests the potential role of Haemaphysalis lagrangei as a Theileria vector in Thailand.

  6. Detection of a Borrelia species in questing Gulf Coast ticks, Amblyomma maculatum.

    PubMed

    Lee, Jung Keun; Smith, Whitney Crow; McIntosh, Chelsea; Ferrari, Flavia Girao; Moore-Henderson, Brittany; Varela-Stokes, Andrea

    2014-06-01

    Borrelia spp. are agents of Lyme disease and relapsing fever, diseases which use Ixodes hard ticks and Ornithodoros soft ticks, respectively, as primary vectors. Some relapsing fever spirochetes, such as B. miyamotoi, are also found in hard ticks. To date, no Borrelia sp. is known to use the hard tick, Amblyomma maculatum, as a vector. However, both B. burgdorferi and B. lonestari were recently detected in A. maculatum removed from hosts. In our study, DNA extracts from 306 questing adult A. maculatum collected in Mississippi in 2009 and 2010 were tested for Borrelia spp. DNA by PCR amplification of flaB and 16S rRNA gene targets. An additional 97 A. maculatum collected in 2013 were tested by amplification of 16S rRNA gene target. Two ticks, one collected in 2009 and the other in 2010, were positive by PCR of the flaB and 16S rRNA gene targets; both were collected from the same location in central Mississippi. Interestingly, 16S rRNA gene amplicons from these two tick extracts were 98% identical to twelve Borrelia spp. including the reptile-associated spirochete B. turcica and Borrelia sp. "tAG158M"; flaB amplicons from these two ticks shared closest identity (89%) to the reptile-associated spirochete, B. turcica. These results demonstrate a Borrelia sp. in unfed A. maculatum ticks that is unique from other species in the NCBI database and in a clade with reptile-associated Borrelia species. Detection of a previously unrecognized Borrelia in a hard tick species generates additional questions regarding the bacterial fauna in these arthropods and warrants further studies to better understand this fauna.

  7. Tick-borne zoonotic bacteria in ticks collected from central Spain.

    PubMed

    Toledo, Alvaro; Olmeda, A Sonia; Escudero, Raquel; Jado, Isabel; Valcárcel, Félix; Casado-Nistal, Miguel A; Rodríguez-Vargas, Manuela; Gil, Horacio; Anda, Pedro

    2009-07-01

    The prevalence of tick-borne and related bacteria infecting adult ticks in central Spain was assessed by molecular methods. Six areas were sampled monthly during a 2-year longitudinal study. A total of 1,038 questing and 442 feeding ticks, belonging to eight different species, were tested. The most abundant species were Hyalomma lusitanicum (54% of captures), followed by Dermacentor marginatus (23%) and Rhipicephalus sanguineus (10%). Four human pathogens, including seven Rickettsia species, Anaplasma phagocytophilum, Borrelia burgdorferi, and Francisella tularensis, were detected at percentages of 19.0, 2.2, 1.7, and 0.5, respectively, whereas Bartonella spp. was never detected. In terms of infection and tick abundance, H. lusitanicum seems to be the most significant tick species in the area, carrying three of the five agents tested, and the anthropophilic tick, D. marginatum, infected with Rickettsia spp. and F. tularensis, is the most relevant in terms of public health. The significance of these data is discussed.

  8. Prevalence of spotted fever group Rickettsia species detected in ticks in La Rioja, Spain.

    PubMed

    Oteo, J A; Portillo, A; Santibáñez, S; Pérez-Martínez, L; Blanco, J R; Jiménez, S; Ibarra, V; Pérez-Palacios, A; Sanz, M

    2006-10-01

    Our objective was to learn the prevalence of spotted fever group (SFG) Rickettsia detected in ticks in La Rioja, in the north of Spain. From 2001 to 2005, 496 ticks representing 7 tick species were analysed at the Hospital de La Rioja. Ticks were removed from humans with or without rickettsial syndrome (n = 59) or collected from mammals (n = 371) or from vegetation by dragging (n = 66). The presence of SFG Rickettsia in these ticks was investigated by semi-nested PCR (ompA gene) and sequencing. A phylogenetic tree using Clustal method (neighbor-joining) was constructed with these data. Only 3 of 170 Hyalomma marginatum ticks carried SFG Rickettsia. Sequencing analysis demonstrated the presence of Rickettsia aeschlimannii (1.8%). Furthermore, Rickettsia massiliae and BAR29 were found in 3 of 120 Rhipicephalus sanguineus specimens (2.5%). In contrast, 81 of 83 tested Dermacentor marginatus ticks were PCR-positive (97%). Rickettsia slovaca (40.6%) and Rickettsia sp. strains RpA4, DnS14, DnS28 and JL-02 (59.3%) were found within this tick species. No SFG Rickettsia was detected using ompA primers when Ixodes ricinus, Rhipicephalus bursa, Rhipicephalus turanicus, Rhipicephalus eversti eversti, Hyalomma detritum scupense and Rhipicephalus sp. were analyzed. We detected 17.5% of ticks associated with different SFG Rickettsia: R. aeschlimannii, R. massiliae, BAR29, R. slovaca and Rickettsia sp. strains RpA4, DnS14, DnS28 and JL-02. Their presence has to be taken into account since most of them have been recognized as human pathogens.

  9. Multiple Pathogens Including Potential New Species in Tick Vectors in Côte d’Ivoire

    PubMed Central

    Ehounoud, Cyrille Bilé; Yao, Kouassi Patrick; Dahmani, Mustapha; Achi, Yaba Louise; Amanzougaghene, Nadia; Kacou N’Douba, Adèle; N’Guessan, Jean David; Raoult, Didier; Fenollar, Florence; Mediannikov, Oleg

    2016-01-01

    Background Our study aimed to assess the presence of different pathogens in ticks collected in two regions in Côte d’Ivoire. Methodology/Principal Findings Real-time PCR and standard PCR assays coupled to sequencing were used. Three hundred and seventy eight (378) ticks (170 Amblyomma variegatum, 161 Rhipicepalus microplus, 3 Rhipicephalus senegalensis, 27 Hyalomma truncatum, 16 Hyalomma marginatum rufipes, and 1 Hyalomma impressum) were identified and analyzed. We identified as pathogenic bacteria, Rickettsia africae in Am. variegatum (90%), Rh. microplus (10%) and Hyalomma spp. (9%), Rickettsia aeschlimannii in Hyalomma spp. (23%), Rickettsia massiliae in Rh. senegalensis (33%) as well as Coxiella burnetii in 0.2%, Borrelia sp. in 0.2%, Anaplasma centrale in 0.2%, Anaplasma marginale in 0.5%, and Ehrlichia ruminantium in 0.5% of all ticks. Potential new species of Borrelia, Anaplasma, and Wolbachia were detected. Candidatus Borrelia africana and Candidatus Borrelia ivorensis (detected in three ticks) are phylogenetically distant from both the relapsing fever group and Lyme disease group borreliae; both were detected in Am. variegatum. Four new genotypes of bacteria from the Anaplasmataceae family were identified, namely Candidatus Anaplasma ivorensis (detected in three ticks), Candidatus Ehrlichia urmitei (in nine ticks), Candidatus Ehrlichia rustica (in four ticks), and Candidatus Wolbachia ivorensis (in one tick). Conclusions/Significance For the first time, we demonstrate the presence of different pathogens such as R. aeschlimannii, C. burnetii, Borrelia sp., A. centrale, A. marginale, and E. ruminantium in ticks in Côte d’Ivoire as well as potential new species of unknown pathogenicity. PMID:26771308

  10. Molecular Evidence of Bartonella Species in Ixodid Ticks and Domestic Animals in Palestine.

    PubMed

    Ereqat, Suheir; Nasereddin, Abdelmajeed; Vayssier-Taussat, Muriel; Abdelkader, Ahmad; Al-Jawabreh, Amer; Zaid, Taher; Azmi, Kifaya; Abdeen, Ziad

    2016-01-01

    Ticks play an important role in disease transmission as vectors for human and animal pathogens, including the Gram-negative pathogen Bartonella. Here, we evaluated the presence of Bartonella in ixodid ticks and domestic animals from Palestine. We tested 633 partly engorged ticks and 139 blood samples from domestic animals (dogs, sheep and camels) for Bartonella using ITS-PCR. Bartonella DNA was detected in 3.9% of the tested ticks. None of the ticks collected from sheep and goats were positive for Bartonella. Seventeen R. sanguineus ticks (17/391; 4.3%) collected from dogs were infected with B. rochalimae (n = 10), B. chomelii (n = 6), and B. koehlerae (n = 1). Four H. dromedarri ticks (4/63; 6.3%) obtained from camels were infected with B. bovis (n = 2) and B. rochalimae (n = 2). Among canine blood samples (n = 110), we found one asymptomatic female dog to be infected with B. rochalimae (0.9%). The detection of zoonotic Bartonella species in this study should raise awareness of these vector-borne diseases among physicians, veterinarians and public health workers and highlight the importance of surveillance and preventive measures in the region.

  11. Molecular Evidence of Bartonella Species in Ixodid Ticks and Domestic Animals in Palestine

    PubMed Central

    Ereqat, Suheir; Nasereddin, Abdelmajeed; Vayssier-Taussat, Muriel; Abdelkader, Ahmad; Al-Jawabreh, Amer; Zaid, Taher; Azmi, Kifaya; Abdeen, Ziad

    2016-01-01

    Ticks play an important role in disease transmission as vectors for human and animal pathogens, including the Gram-negative pathogen Bartonella. Here, we evaluated the presence of Bartonella in ixodid ticks and domestic animals from Palestine. We tested 633 partly engorged ticks and 139 blood samples from domestic animals (dogs, sheep and camels) for Bartonella using ITS-PCR. Bartonella DNA was detected in 3.9% of the tested ticks. None of the ticks collected from sheep and goats were positive for Bartonella. Seventeen R. sanguineus ticks (17/391; 4.3%) collected from dogs were infected with B. rochalimae (n = 10), B. chomelii (n = 6), and B. koehlerae (n = 1). Four H. dromedarri ticks (4/63; 6.3%) obtained from camels were infected with B. bovis (n = 2) and B. rochalimae (n = 2). Among canine blood samples (n = 110), we found one asymptomatic female dog to be infected with B. rochalimae (0.9%). The detection of zoonotic Bartonella species in this study should raise awareness of these vector-borne diseases among physicians, veterinarians and public health workers and highlight the importance of surveillance and preventive measures in the region. PMID:27540374

  12. Crimean-Congo Hemorrhagic Fever Virus Clade IV (Asia 1) in Ticks of Western Iran.

    PubMed

    Kayedi, Mohammad Hassan; Chinikar, Sadegh; Mostafavi, Ehsan; Khakifirouz, Sahar; Jalali, Tahmineh; Hosseini-Chegeni, Asadolah; Naghizadeh, Ali; Niedrig, Matthias; Fooks, Anthony R; Shahhosseini, Nariman

    2015-09-01

    Crimean-Congo Hemorrhagic Fever virus (CCHFV) is transmitted through the bite of an infected tick, or by direct contact with CCHFV-infected patients' blood or the products of infected livestock. In 2012, ticks were collected in eight regions of Lorestan Province, Iran. In total, 434 ticks were collected. Reverse transcriptase polymerase chain reaction was used for the detection of CCHFV RNA. Of 434 ticks, 419 (96.6%) ticks were from the family Ixodidae (hard ticks) and 15 (3.5%) ticks were from the family Argasidae (soft ticks). The presence of CCHFV RNA was detected in 29 (6.7%) of 434 ticks. The infected tick species include Hyalomma asiaticum (n = 7, 7.4%), Hyalomma anatolicum (n = 12, 13.2%), Hyalomma marginatum (n = 1, 16.7%), and Rhipicephalus sanguineus (n = 9, 4.3%). These empirical data demonstrated that the majority of CCHFV-positive ticks belonged to the Ixodidae. None of the Argasidae and Haemaphysalis sulcata species was infected with CCHFV. The phylogenetic analyses of the tick-derived CCHFV strains revealed that all 29 viral strains fell in clade IV (Asia 1). The most abundant species of tick collected in this study was R. sanguineus followed by different species of Hyalomma. Given the infection rate among collected ticks, H. marginatum was the most abundant infected tick species (16.7%) followed by H. anatolicum (13.2%), H. asiaticum (7.4%), and R. sanguineus (4.3%).

  13. Spotted fever Rickettsia species in Hyalomma and Ixodes ticks infesting migratory birds in the European Mediterranean area

    PubMed Central

    2014-01-01

    Background A few billion birds migrate annually between their breeding grounds in Europe and their wintering grounds in Africa. Many bird species are tick-infested, and as a result of their innate migratory behavior, they contribute significantly to the geographic distribution of pathogens, including spotted fever rickettsiae. The aim of the present study was to characterize, in samples from two consecutive years, the potential role of migrant birds captured in Europe as disseminators of Rickettsia-infected ticks. Methods Ticks were collected from a total of 14,789 birds during their seasonal migration northwards in spring 2009 and 2010 at bird observatories on two Mediterranean islands: Capri and Antikythira. All ticks were subjected to RNA extraction followed by cDNA synthesis and individually assayed with a real-time PCR targeting the citrate synthase (gltA) gene. For species identification of Rickettsia, multiple genes were sequenced. Results Three hundred and ninety-eight (2.7%) of all captured birds were tick-infested; some birds carried more than one tick. A total number of 734 ticks were analysed of which 353 ± 1 (48%) were Rickettsia-positive; 96% were infected with Rickettsia aeschlimannii and 4% with Rickettsia africae or unidentified Rickettsia species. The predominant tick taxon, Hyalomma marginatum sensu lato constituted 90% (n = 658) of the ticks collected. The remaining ticks were Ixodes frontalis, Amblyomma sp., Haemaphysalis sp., Rhipicephalus sp. and unidentified ixodids. Most ticks were nymphs (66%) followed by larvae (27%) and adult female ticks (0.5%). The majority (65%) of ticks was engorged and nearly all ticks contained visible blood. Conclusions Migratory birds appear to have a great impact on the dissemination of Rickettsia-infected ticks, some of which may originate from distant locations. The potential ecological, medical and veterinary implications of such Rickettsia infections need further examination. PMID:25011617

  14. Morphological, molecular and MALDI-TOF mass spectrometry identification of ixodid tick species collected in Oromia, Ethiopia.

    PubMed

    Kumsa, Bersissa; Laroche, Maureen; Almeras, Lionel; Mediannikov, Oleg; Raoult, Didier; Parola, Philippe

    2016-11-01

    Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) technology has recently been reported as a promising method for arthropods identification. More recently, our laboratory reported the correct identification of tick species via the MALDI-TOF MS protein spectra profiling of legs from fresh specimens. The aim of the present study was to assess the use of MALDI-TOF MS for correct identification of ixodid tick species preserved in 70 % ethanol during field collection in Ethiopia. Following morphological identification of 12 tick species, the legs from 85 tick specimens were subjected to MALDI-TOF MS. Spectral analysis revealed an intra-species reproducibility and inter-species specificity that were consistent with the morphological classification. To support the results of the MALDI-TOF MS tick species identification, 41 tick specimens comprising 3 to 5 specimens per tick species were used to create a reference spectra database, which was evaluated using the spectra of the 44 remaining tick specimens. The blind tests revealed that 100 % of the tick specimens studied by MALDI-TOF MS were correctly identified. A relevant Log score value (LSV) of >1.8 was recorded for all of the tick species studied by MALDI-TOF MS, except for Rhipicephalus praetextatus. The morphological and MALDI-TOF MS identifications were confirmed by sequencing the 12S ribosomal RNA (rRNA) gene of 40 tick specimens belonging to 11 ixodid species. Taken together, the results of the present study indicate that MALDI-TOF MS is a reliable tool for tick species identification, even after preservation in ethanol, provided that a reference spectra database is built from specimens that represent the respective species stored under the same conditions.

  15. Observations on changes in abundance of questing Ixodes ricinus, castor bean tick, over a 35-year period in the eastern part of its range (Russia, Tula region).

    PubMed

    Korotkov, Yu; Kozlova, T; Kozlovskaya, L

    2015-06-01

    Ixodes ricinus (Acari: Ixodidae) L. transmit a wide variety of pathogens to vertebrates including viruses, bacteria and protozoa. Understanding of the epidemiology of tick-borne infections requires basic knowledge of the regional and local factors influencing tick population dynamics. The present study describes the results of monitoring of a questing I. ricinus population, conducted over 35 years (1977-2011) in the eastern, poorly studied part of its range (Russia, Tula region). We have found that the multiannual average abundance of ticks is small and varies depending on the biotope and degree of urban transformation. Tick abundance for the first 14 years of observations (1977-1990) was at the lower limit of the sensitivity of our methods throughout the study area (0.1-0.9 specimens per 1-km transect). In the following 21 years (1991-2011), a manifold increase in abundance was observed, which reached 18.1 ± 1.8 individuals per 1-km transect in moist floodplain terraces, and 4.8 ± 0.9 in xerophylic hill woods. Long-term growth of tick abundance occurred in spite of a relatively constant abundance of small mammals and only minor fluctuations in the abundance of large wild animals. Climate and anthropogenic changes appear to be the main contributors to increased abundance of the tick.

  16. A global database of ant species abundances

    USGS Publications Warehouse

    Gibb, Heloise; Dunn, Rob R.; Sanders, Nathan J.; Grossman, Blair F.; Photakis, Manoli; Abril, Silvia; Agosti, Donat; Andersen, Alan N.; Angulo, Elena; Armbrecht, Ingre; Arnan, Xavier; Baccaro, Fabricio B.; Bishop, Tom R.; Boulay, Raphael; Bruhl, Carsten; Castracani, Cristina; Cerda, Xim; Del Toro, Israel; Delsinne, Thibaut; Diaz, Mireia; Donoso, David A.; Ellison, Aaron M.; Enriquez, Martha L.; Fayle, Tom M.; Feener Jr., Donald H.; Fisher, Brian L.; Fisher, Robert N.; Fitpatrick, Matthew C.; Gomez, Cristanto; Gotelli, Nicholas J.; Gove, Aaron; Grasso, Donato A.; Groc, Sarah; Guenard, Benoit; Gunawardene, Nihara; Heterick, Brian; Hoffmann, Benjamin; Janda, Milan; Jenkins, Clinton; Kaspari, Michael; Klimes, Petr; Lach, Lori; Laeger, Thomas; Lattke, John; Leponce, Maurice; Lessard, Jean-Philippe; Longino, John; Lucky, Andrea; Luke, Sarah H.; Majer, Jonathan; McGlynn, Terrence P.; Menke, Sean; Mezger, Dirk; Mori, Alessandra; Moses, Jimmy; Munyai, Thinandavha Caswell; Pacheco, Renata; Paknia, Omid; Pearce-Duvet, Jessica; Pfeiffer, Martin; Philpott, Stacy M.; Resasco, Julian; Retana, Javier; Silva, Rogerio R.; Sorger, Magdalena D.; Souza, Jorge; Suarez, Andrew V.; Tista, Melanie; Vasconcelos, Heraldo L.; Vonshak, Merav; Weiser, Michael D.; Yates, Michelle; Parr, Catherine L.

    2017-01-01

    What forces structure ecological assemblages? A key limitation to general insights about assemblage structure is the availability of data that are collected at a small spatial grain (local assemblages) and a large spatial extent (global coverage). Here, we present published and unpublished data from 51,388 ant abundance and occurrence records of more than 2693 species and 7953 morphospecies from local assemblages collected at 4212 locations around the world. Ants were selected because they are diverse and abundant globally, comprise a large fraction of animal biomass in most terrestrial communities, and are key contributors to a range of ecosystem functions. Data were collected between 1949 and 2014, and include, for each geo-referenced sampling site, both the identity of the ants collected and details of sampling design, habitat type and degree of disturbance. The aim of compiling this dataset was to provide comprehensive species abundance data in order to test relationships between assemblage structure and environmental and biogeographic factors. Data were collected using a variety of standardised methods, such as pitfall and Winkler traps, and will be valuable for studies investigating large-scale forces structuring local assemblages. Understanding such relationships is particularly critical under current rates of global change. We encourage authors holding additional data on systematically collected ant assemblages, especially those in dry and cold, and remote areas, to contact us and contribute their data to this growing dataset.

  17. A global database of ant species abundances.

    PubMed

    Gibb, Heloise; Dunn, Rob R; Sanders, Nathan J; Grossman, Blair F; Photakis, Manoli; Abril, Silvia; Agosti, Donat; Andersen, Alan N; Angulo, Elena; Armbrecht, Inge; Arnan, Xavier; Baccaro, Fabricio B; Bishop, Tom R; Boulay, Raphaël; Brühl, Carsten; Castracani, Cristina; Cerda, Xim; Del Toro, Israel; Delsinne, Thibaut; Diaz, Mireia; Donoso, David A; Ellison, Aaron M; Enriquez, Martha L; Fayle, Tom M; Feener, Donald H; Fisher, Brian L; Fisher, Robert N; Fitzpatrick, Matthew C; Gómez, Crisanto; Gotelli, Nicholas J; Gove, Aaron; Grasso, Donato A; Groc, Sarah; Guenard, Benoit; Gunawardene, Nihara; Heterick, Brian; Hoffmann, Benjamin; Janda, Milan; Jenkins, Clinton; Kaspari, Michael; Klimes, Petr; Lach, Lori; Laeger, Thomas; Lattke, John; Leponce, Maurice; Lessard, Jean-Philippe; Longino, John; Lucky, Andrea; Luke, Sarah H; Majer, Jonathan; McGlynn, Terrence P; Menke, Sean; Mezger, Dirk; Mori, Alessandra; Moses, Jimmy; Munyai, Thinandavha Caswell; Pacheco, Renata; Paknia, Omid; Pearce-Duvet, Jessica; Pfeiffer, Martin; Philpott, Stacy M; Resasco, Julian; Retana, Javier; Silva, Rogerio R; Sorger, Magdalena D; Souza, Jorge; Suarez, Andrew; Tista, Melanie; Vasconcelos, Heraldo L; Vonshak, Merav; Weiser, Michael D; Yates, Michelle; Parr, Catherine L

    2017-03-01

    What forces structure ecological assemblages? A key limitation to general insights about assemblage structure is the availability of data that are collected at a small spatial grain (local assemblages) and a large spatial extent (global coverage). Here, we present published and unpublished data from 51 ,388 ant abundance and occurrence records of more than 2,693 species and 7,953 morphospecies from local assemblages collected at 4,212 locations around the world. Ants were selected because they are diverse and abundant globally, comprise a large fraction of animal biomass in most terrestrial communities, and are key contributors to a range of ecosystem functions. Data were collected between 1949 and 2014, and include, for each geo-referenced sampling site, both the identity of the ants collected and details of sampling design, habitat type, and degree of disturbance. The aim of compiling this data set was to provide comprehensive species abundance data in order to test relationships between assemblage structure and environmental and biogeographic factors. Data were collected using a variety of standardized methods, such as pitfall and Winkler traps, and will be valuable for studies investigating large-scale forces structuring local assemblages. Understanding such relationships is particularly critical under current rates of global change. We encourage authors holding additional data on systematically collected ant assemblages, especially those in dry and cold, and remote areas, to contact us and contribute their data to this growing data set.

  18. Bacterial Profiling Reveals Novel "Ca. Neoehrlichia", Ehrlichia, and Anaplasma Species in Australian Human-Biting Ticks.

    PubMed

    Gofton, Alexander W; Doggett, Stephen; Ratchford, Andrew; Oskam, Charlotte L; Paparini, Andrea; Ryan, Una; Irwin, Peter

    2015-01-01

    In Australia, a conclusive aetiology of Lyme disease-like illness in human patients remains elusive, despite growing numbers of people presenting with symptoms attributed to tick bites. In the present study, we surveyed the microbial communities harboured by human-biting ticks from across Australia to identify bacteria that may contribute to this syndrome. Universal PCR primers were used to amplify the V1-2 hyper-variable region of bacterial 16S rRNA genes in DNA samples from individual Ixodes holocyclus (n = 279), Amblyomma triguttatum (n = 167), Haemaphysalis bancrofti (n = 7), and H. longicornis (n = 7) ticks. The 16S amplicons were sequenced on the Illumina MiSeq platform and analysed in USEARCH, QIIME, and BLAST to assign genus and species-level taxonomies. Nested PCR and Sanger sequencing were used to confirm the NGS data and further analyse novel findings. All 460 ticks were negative for Borrelia spp. by both NGS and nested PCR analysis. Two novel "Candidatus Neoehrlichia" spp. were identified in 12.9% of I. holocyclus ticks. A novel Anaplasma sp. was identified in 1.8% of A. triguttatum ticks, and a novel Ehrlichia sp. was identified in both A. triguttatum (1.2%) ticks and a single I. holocyclus (0.6%) tick. Further phylogenetic analysis of novel "Ca. Neoehrlichia", Anaplasma and Ehrlichia based on 1,265 bp 16S rRNA gene sequences suggests that these are new species. Determining whether these newly discovered organisms cause disease in humans and animals, like closely related bacteria do abroad, is of public health importance and requires further investigation.

  19. Tick infestation patterns in free ranging African buffalo (Syncercus caffer): Effects of host innate immunity and niche segregation among tick species☆

    PubMed Central

    Anderson, Kadie; Ezenwa, Vanessa O.; Jolles, Anna E.

    2012-01-01

    Ticks are of vast importance to livestock health, and contribute to conflicts between wildlife conservation and agricultural interests; but factors driving tick infestation patterns on wild hosts are not well understood. We studied tick infestation patterns on free-ranging African buffalo (Syncercus caffer), asking (i) is there evidence for niche segregation among tick species?; and (ii) how do host characteristics affect variation in tick abundance among hosts? We identified ticks and estimated tick burdens on 134 adult female buffalo from two herds at Kruger National Park, South Africa. To assess niche segregation, we evaluated attachment site preferences and tested for correlations between abundances of different tick species. To investigate which host factors may drive variability in tick abundance, we measured age, body condition, reproductive and immune status in all hosts, and examined their effects on tick burdens. Two tick species were abundant on buffalo, Amblyomma hebraeum and Rhipicephalus evertsi evertsi. A. hebraeum were found primarily in the inguinal and axillary regions; R. e. evertsi attached exclusively in the perianal area. Abundances of A. hebraeum and R. e. evertsi on the host were unrelated. These results suggest spatial niche segregation between A. hebraeum and R. e. evertsi on the buffalo. Buffalo with stronger innate immunity, and younger buffalo, had fewer ticks. Buffalo with low body condition scores, and pregnant buffalo, had higher tick burdens, but these effects varied between the two herds we sampled. This study is one of the first to link ectoparasite abundance patterns and immunity in a free-ranging mammalian host population. Based on independent abundances of A. hebraeum and R. e. evertsi on individual buffalo, we would expect no association between the diseases these ticks transmit. Longitudinal studies linking environmental variability with host immunity are needed to understand tick infestation patterns and the dynamics of tick

  20. New Rickettsia species in soft ticks Ornithodoros hasei collected from bats in French Guiana.

    PubMed

    Tahir, Djamel; Socolovschi, Cristina; Marié, Jean-Lou; Ganay, Gautier; Berenger, Jean-Michel; Bompar, Jean-Michel; Blanchet, Denis; Cheuret, Marie; Mediannikov, Oleg; Raoult, Didier; Davoust, Bernard; Parola, Philippe

    2016-10-01

    In French Guiana, located on the northeastern coast of South America, bats of different species are very numerous. The infection of bats and their ticks with zoonotic bacteria, especially Rickettsia species, is so far unknown. In order to improve knowledge of these zoonotic pathogens in this French overseas department, the presence and diversity of tick-borne bacteria was investigated with molecular tools in bat ticks. In the beginning of 2013, 32 bats were caught in Saint-Jean-du-Maroni, an area close to the coast of French Guiana, and the ticks of these animals were collected. A total of 354 larvae of Argasidae soft ticks (Ornithodoros hasei) from 12 bats (Noctilio albiventris) were collected and 107 of them were analysed. DNA was extracted from the samples and quantitative real-time PCR was carried out to detect Rickettsia spp., Bartonella spp., Borrelia spp. and Coxiella burnetii. All tested samples were negative for Bartonella spp., Borrelia spp. and Coxiella burnetii. Rickettsia DNA was detected in 31 (28.9%) ticks. An almost entire (1118 base pairs long) sequence of the gltA gene was obtained after the amplification of some positive samples on conventional PCR and sequencing. A Bayesian tree was constructed using concatenated rrs, gltA, ompA, ompB, and gene D sequences. The study of characteristic sequences shows that this Rickettsia species is very close (98.3-99.8%) genetically to R. peacockii. Nevertheless, the comparative analysis of sequences obtained from gltA, ompA, ompB, rrs and gene D fragments demonstrated that this Rickettsia is different from the other members of the spotted fever group. The sequences of this new species were deposited in GenBank as Candidatus Rickettsia wissemanii. This is the first report showing the presence of nucleic acid of Rickettsia in Ornithodoros hasei ticks from South American bats.

  1. Evaluation of Gulf Coast Ticks (Acari: Ixodidae) for Ehrlichia and Anaplasma Species.

    PubMed

    Allerdice, Michelle E J; Hecht, Joy A; Karpathy, Sandor E; Paddock, Christopher D

    2017-03-01

    Amblyomma maculatum Koch (the Gulf Coast tick) is an aggressive, human-biting ixodid tick distributed throughout much of the southeastern United States and is the primary vector for Rickettsia parkeri, an emerging human pathogen. Amblyomma maculatum has diverse host preferences that include white-tailed deer, a known reservoir for Ehrlichia and Anaplasma species, including the human pathogens E. ewingii and E. chaffeensis. To examine more closely the potential role of A. maculatum in the maintenance of various pathogenic Ehrlichia and Anaplasma species, we screened DNA samples from 493 questing adult A. maculatum collected from six U.S. states using broad-range Anaplasmataceae and Ehrlichia genus-specific PCR assays. Of the samples tested, four (0.8%) were positive for DNA of Ehrlichia ewingii, one (0.2%) was positive for Anaplasma platys, and one (0.2%) was positive for a previously unreported Ehrlichia species closely related to Ehrlichia muris and an uncultivated Ehrlichia species from Haemaphysalis longicornis ticks in Japan. No ticks contained DNA of Ehrlichia chaffeensis, Ehrlichia canis, the Panola Mountain Ehrlichia, or Anaplasma phagocytophilum. This is the first identification of E. ewingii, A. platys, and the novel Ehrlichia in questing Gulf Coast ticks; nonetheless the low prevalence of these agents suggests that A. maculatum is not likely an important vector of these zoonotic pathogens.

  2. Abundance of introduced species at home predicts abundance away in herbaceous communities

    USGS Publications Warehouse

    Firn, Jennifer; Moore, Joslin L.; MacDougall, Andrew S.; Borer, Elizabeth T.; Seabloom, Eric W.; HilleRisLambers, Janneke; Harpole, W. Stanley; Cleland, Elsa E.; Brown, Cynthia S.; Knops, Johannes M.H.; Prober, Suzanne M.; Pyke, David A.; Farrell, Kelly A.; Bakker, John D.; O'Halloran, Lydia R.; Adler, Peter B.; Collins, Scott L.; D'Antonio, Carla M.; Crawley, Michael J.; Wolkovich, Elizabeth M.; La Pierre, Kimberly J.; Melbourne, Brett A.; Hautier, Yann; Morgan, John W.; Leakey, Andrew D.B.; Kay, Adam; McCulley, Rebecca; Davies, Kendi F.; Stevens, Carly J.; Chu, Cheng-Jin; Holl, Karen D.; Klein, Julia A.; Fay, Phillip A.; Hagenah, Nicole; Kirkman, Kevin P.; Buckley, Yvonne M.

    2011-01-01

    Many ecosystems worldwide are dominated by introduced plant species, leading to loss of biodiversity and ecosystem function. A common but rarely tested assumption is that these plants are more abundant in introduced vs. native communities, because ecological or evolutionary-based shifts in populations underlie invasion success. Here, data for 26 herbaceous species at 39 sites, within eight countries, revealed that species abundances were similar at native (home) and introduced (away) sites - grass species were generally abundant home and away, while forbs were low in abundance, but more abundant at home. Sites with six or more of these species had similar community abundance hierarchies, suggesting that suites of introduced species are assembling similarly on different continents. Overall, we found that substantial changes to populations are not necessarily a pre-condition for invasion success and that increases in species abundance are unusual. Instead, abundance at home predicts abundance away, a potentially useful additional criterion for biosecurity programmes.

  3. Abundance of introduced species at home predicts abundance away in herbaceous communities.

    PubMed

    Firn, Jennifer; Moore, Joslin L; MacDougall, Andrew S; Borer, Elizabeth T; Seabloom, Eric W; HilleRisLambers, Janneke; Harpole, W Stanley; Cleland, Elsa E; Brown, Cynthia S; Knops, Johannes M H; Prober, Suzanne M; Pyke, David A; Farrell, Kelly A; Bakker, John D; O'Halloran, Lydia R; Adler, Peter B; Collins, Scott L; D'Antonio, Carla M; Crawley, Michael J; Wolkovich, Elizabeth M; La Pierre, Kimberly J; Melbourne, Brett A; Hautier, Yann; Morgan, John W; Leakey, Andrew D B; Kay, Adam; McCulley, Rebecca; Davies, Kendi F; Stevens, Carly J; Chu, Cheng-Jin; Holl, Karen D; Klein, Julia A; Fay, Philip A; Hagenah, Nicole; Kirkman, Kevin P; Buckley, Yvonne M

    2011-03-01

    Many ecosystems worldwide are dominated by introduced plant species, leading to loss of biodiversity and ecosystem function. A common but rarely tested assumption is that these plants are more abundant in introduced vs. native communities, because ecological or evolutionary-based shifts in populations underlie invasion success. Here, data for 26 herbaceous species at 39 sites, within eight countries, revealed that species abundances were similar at native (home) and introduced (away) sites - grass species were generally abundant home and away, while forbs were low in abundance, but more abundant at home. Sites with six or more of these species had similar community abundance hierarchies, suggesting that suites of introduced species are assembling similarly on different continents. Overall, we found that substantial changes to populations are not necessarily a pre-condition for invasion success and that increases in species abundance are unusual. Instead, abundance at home predicts abundance away, a potentially useful additional criterion for biosecurity programmes.

  4. Ticks (Acarina: Ixodida) infesting five reptile species in Sri Lanka with sixteen new host records.

    PubMed

    Liyanaarachchi, Dilrukshi R; Rajakaruna, Rupika S; Dikkumbura, Anil W; De Silva, Anslem; Rajapakse, R P V Jayantha

    2015-05-29

    The first study on ticks on reptiles of Sri Lanka dates back to Seneviratna (1965) who reported ticks from five reptiles. Later studies were either limited to one reptile (Fernando & Fernando 2012), or captive animals in zoos (Fernando & Randeniaya 2009) and household pets (Nathanael et al. 2004). According to the current classification (Guglielmone et al. 2010), all the tick species previously recorded on reptiles belong to five species of Amblyomma: A. clypeolatum Neumann, A. gervaisi (Lucas), A. pattoni (Neumann), A. trimaculatum (Lucas) and A. varanense (Supino). Some of the species listed by Seneviratna (1965) were either synonyms or invalid in respect to the present classification. For example Amblyomma laeve sensu Warburton (1910) is a junior synonym of A. pattoni and A. gervaisii var. lucasi is considered a junior synonym of A. varanense (Guglielmone et al. 2010; D. Apanaskevich pers. comm.).

  5. [Tick (Ixodoidea) and flea (Siphonaptera) species on three red foxes (Vulpes vulpes) in Erzurum province].

    PubMed

    Aydın, Mehmet Fatih; Balkaya, Ibrahim; Aktaş, Münir; Dumanlı, Nazir

    2011-01-01

    In this study, three red foxes (Vulpes vulpes) which died after traffic accidents were examined in terms of ectoparasites, in the province of Erzurum in January of 2009. 13 ticks and 74 fleas were collected from the foxes and taken to the laboratory in separate glasses containing 70% alcohol. Ticks were taken directly from 70% alcohol and have been identified under the stereo microscope. Fleas were cleared in 10% KOH solution during 4-13 days and washed in distilled water 3-4 times and were identified under the light microscope. Two tick species Ixodes hexagonus Leach, 1815 (5 males, 7 females) and Haemaphysalis numidiana Neumann, 1905 (1 male) and four flea species Pulex irritans Linne, 1758 (23 males, 37 females), Chaetopsylla globiceps Tacshenberg, 1880 (11 female), Ctenocephalides canis Curtis, 1826 (2 female) and Ctenocephalides felis felis Bouche, 1835 (1 female) were identified. In this study H. numidiana have been identified in the fox for the first time.

  6. Modeling species-abundance relationships in multi-species collections

    USGS Publications Warehouse

    Peng, S.; Yin, Z.; Ren, H.; Guo, Q.

    2003-01-01

    Species-abundance relationship is one of the most fundamental aspects of community ecology. Since Motomura first developed the geometric series model to describe the feature of community structure, ecologists have developed many other models to fit the species-abundance data in communities. These models can be classified into empirical and theoretical ones, including (1) statistical models, i.e., negative binomial distribution (and its extension), log-series distribution (and its extension), geometric distribution, lognormal distribution, Poisson-lognormal distribution, (2) niche models, i.e., geometric series, broken stick, overlapping niche, particulate niche, random assortment, dominance pre-emption, dominance decay, random fraction, weighted random fraction, composite niche, Zipf or Zipf-Mandelbrot model, and (3) dynamic models describing community dynamics and restrictive function of environment on community. These models have different characteristics and fit species-abundance data in various communities or collections. Among them, log-series distribution, lognormal distribution, geometric series, and broken stick model have been most widely used.

  7. Diversity and distribution of tick species (Acari: Ixodidae) associated with human otoacariasis and socio-ecological risk factors of tick infestations in Sri Lanka.

    PubMed

    Ariyarathne, S; Apanaskevich, D A; Amarasinghe, P H; Rajakaruna, R S

    2016-09-01

    Tick infestation in humans is a major public health concern. The diversity and distribution of tick species associated with human otoacariasis was studied in five districts: Anuradhapura, Kandy, Kurunegala, Nuwara Eliya and Ratnapura in the main agro-climatic zones of Sri Lanka. Ticks from patients attending the ear, nose and throat clinics of the General Hospitals were collected during a 3 year period. In total 426 ticks were collected. Most human otoacariasis cases were reported from Kandy (33.8 %) and the fewest from Nuwara Eliya (8.2 %). Of the five tick species identified, nymphs of Dermacentor auratus constituted 90.6 % of the collection. Rhipicephalus sanguineus, Hyalomma isaaci, Haemaphysalis bispinosa and Otobius megnini were found rarely infesting humans possibly as an accidental host; H. bispinosa and O. megnini in the human ear canal were first time records in Sri Lanka. Females and children under 10 years were identified as risk groups of human otoacariasis. Subsequently, a field study was carried out to determine socio-ecological risk factors of human tick infestations in the five districts. Based on hospital data, eight villages with high prevalence of otoacariasis were selected from each district. A total 40 villages were visited and 1674 household members were interviewed. Involvement in outdoor activities, presence of wild animals around the house, location of the house in close proximity to a forest and occupation were identified as major risk factors.

  8. Molecular Detection of Rickettsia Species Within Ticks (Acari: Ixodidae) Collected from Arkansas United States.

    PubMed

    Trout Fryxell, R T; Steelman, C D; Szalanski, A L; Billingsley, P M; Williamson, P C

    2015-05-01

    Rocky Mountain spotted fever (RMSF), caused by the etiological agent Rickettsia rickettsii, is the most severe and frequently reported rickettsial illness in the United States, and is commonly diagnosed throughout the southeast. With the discoveries of Rickettsia parkeri and other spotted fever group rickettsiae (SFGR) in ticks, it remains inconclusive if the cases reported as RMSF are truly caused by R. rickettsii or other SFGR. Arkansas reports one of the highest incidence rates of RMSF in the country; consequently, to identify the rickettsiae in Arkansas, 1,731 ticks, 250 white-tailed deer, and 189 canines were screened by polymerase chain reaction (PCR) for the rickettsial genes gltA, rompB, and ompA. None of the white-tailed deer were positive, while two of the canines (1.1%) and 502 (29.0%) of the ticks were PCR positive. Five different tick species were PCR positive: 244 (37%) Amblyomma americanum L., 130 (38%) Ixodes scapularis Say, 65 (39%) Amblyomma maculatum (Koch), 30 (9%) Rhipicephalus sanguineus Latreille, 7 (4%) Dermacentor variabilis Say, and 26 (44%) unidentified Amblyomma ticks. None of the sequenced products were homologous to R. rickettsii. The most common Rickettsia via rompB amplification was Rickettsia montanensis and nonpathogenic Candidatus Rickettsia amblyommii, whereas with ompA amplification the most common Rickettsia was Ca. R. amblyommii. Many tick specimens collected in northwest Arkansas were PCR positive and these were commonly A. americanum harboring Ca. R. amblyommii, a currently nonpathogenic Rickettsia. Data reported here indicate that pathogenic R. rickettsii was absent from these ticks and suggest by extension that other SFGR are likely the causative agents for Arkansas diagnosed RMSF cases.

  9. Detection of a new Borrelia species in ticks taken from cattle in Southwest Ethiopia.

    PubMed

    Mediannikov, Oleg; Abdissa, Alemseged; Socolovschi, Cristina; Diatta, Georges; Trape, Jean-François; Raoult, Didier

    2013-04-01

    We collected 284 ticks in Ethiopia (109 Amblyomma cohaerens, 173 Rhipicephalus decoloratus, and 2 Rhipicephalus praetextatus). We found no rickettsiae and bartonellae. In 7.3% of the A. cohaerens, we found a Borrelia sp. that may represent a new species distant from both relapsing fever group and Lyme borreliae.

  10. Detection and identification of Rickettsia species in Ixodes tick populations from Estonia.

    PubMed

    Katargina, Olga; Geller, Julia; Ivanova, Anna; Värv, Kairi; Tefanova, Valentina; Vene, Sirkka; Lundkvist, Åke; Golovljova, Irina

    2015-09-01

    A total of 1640 ticks collected in different geographical parts of Estonia were screened for the presence of Rickettsia species DNA by real-time PCR. DNA of Rickettsia was detected in 83 out of 1640 questing ticks with an overall prevalence of 5.1%. The majority of the ticks infected by rickettsiae were Ixodes ricinus (74 of 83), while 9 of the 83 positive ticks were Ixodes persulcatus. For rickettsial species identification, a part of the citrate synthase gltA gene was sequenced. The majority of the positive samples were identified as Rickettsia helvetica (81 out of 83) and two of the samples were identified as Rickettsia monacensis and Candidatus R. tarasevichiae, respectively. Genetic characterization based on the partial gltA gene showed that the Estonian sequences within the R. helvetica, R. monacensis and Candidatus R. tarasevichiae species demonstrated 100% similarity with sequences deposited in GenBank, originating from Rickettsia species distributed over large territories from Europe to Asia.

  11. Real-time PCR-based identification of Borrelia burgdorferi sensu lato species in ticks collected from humans in Romania.

    PubMed

    Briciu, Violeta T; Meyer, Fabian; Sebah, Daniela; Tăţulescu, Doina F; Coroiu, Georgiana; Lupşe, Mihaela; Carstina, Dumitru; Mihalca, Andrei D; Hizo-Teufel, Cecilia; Klier, Christiane; Huber, Ingrid; Fingerle, Volker

    2014-09-01

    The aims of our study were to determine (i) which tick species bite humans in Romania and (ii) the prevalence of Borrelia (B.) burgdorferi genospecies in these ticks. All ticks collected from patients who presented to the Clinic of Infectious Diseases Cluj Napoca in spring/summer 2010 were morphologically identified by an entomologist and tested for B. burgdorferi genospecies prevalence by a real-time PCR assay targeting the hbb gene and melting curve analysis. Out of 532 ticks, 518 were Ixodes ricinus, 10 Dermacentor marginatus, and 3 Haemaphysalis spp. ticks, and one unidentified tick due to destruction. Since evaluation of the hbb PCR revealed that it was not possible to differentiate between B. spielmanii/B. valaisiana and B. garinii/B. bavariensis, sequencing of an 800-bp fragment of the ospA gene was performed in these cases. Out of 389 investigated ticks, 43 were positive by hbb PCR for B. burgdorferi sensu lato. The positive samples were 42 Ixodes ricinus (11.1% B. burgdorferi sensu lato prevalence) and the one unidentified tick. Species identification revealed the presence of mainly B. afzelii, but also of B. garinii, B. burgdorferi sensu stricto, B. valaisiana, and B. lusitaniae. In 4 samples, differentiation between B. spielmanii/B. valaisiana was impossible. Our study shows that the most relevant human pathogenic B. burgdorferi genospecies - predominantly B. afzelii - are present in ticks collected from Romanian patients.

  12. Spotted Fever Group Rickettsiae in Multiple Hard Tick Species from Fairfax County, Virginia

    PubMed Central

    Orr, John M.; Smith, Joshua D.; Arias, Jorge R.; Norris, Douglas E.

    2014-01-01

    Abstract Spotted fever group rickettsiosis (SFGR) is a potentially fatal disease that has displayed increasing incidence in the United States in recent years. The most well-known and severe type of this disease is Rocky Mountain spotted fever, but there are other mild forms that occur. Recently, human infection with Rickettsia parkeri has been reported and linked with the tick Amblyomma maculatum. In 2010, a population of R. parkeri-infected A. maculatum was discovered in Fairfax County, Virginia, leading to increased surveillance of tick species. In this study, we report the presence of R. parkeri in Rhipicephalus sanguineus, Haemaphysalis leporispalustris, and Dermacentor variabilis in Fairfax County. R. parkeri was discovered in two Rh. sanguineus, one H. leporispalustris, and 17 D. variabilis. These findings suggest that spillover infections of R. parkeri may be occurring in tick species not typically associated with this pathogen; however, vector competence studies need to be conducted to determine if these tick species can serve as potential vectors for human SFGR. PMID:24978651

  13. Molecular detection of Rickettsia species in Amblyomma ticks collected from snakes in Thailand.

    PubMed

    Sumrandee, Chalao; Hirunkanokpun, Supanee; Doornbos, Kathryn; Kitthawee, Sangvorn; Baimai, Visut; Grubhoffer, Libor; Trinachartvanit, Wachareeporn; Ahantarig, Arunee

    2014-10-01

    Some reptile ticks are potential vectors of pathogens such as spotted fever group (SFG) rickettsiae. Here, we report for the first time in detail the molecular evidence, DNA sequences and phylogenetic studies, for the presence of Rickettsia spp. in Amblyomma ticks (Amblyomma helvolum and Amblyomma varanense) from snakes in Thailand. A total of 24 tick samples was collected from 4 snake species and identified. A phylogenetic analysis inferred from the partial sequences of the gltA gene indicated that the Rickettsia spp. from 2 Amblyomma helvolum and 1 Amblyomma varanense belong to the same group as the SFG rickettsiae, which are closely related to Rickettsia raoultii strains. In contrast, there was 1 Rickettsia sp. from Amblyomma helvolum grouped into the same clade with other SFG rickettsiae (Rickettsia tamurae, Rickettsia monacensis, and a Rickettsia endosymbiont of Amblyomma dubitatum from Brazil). However, another Rickettsia sp. from Amblyomma varanense was closely related to Rickettsia bellii and Rickettsia sp. strain RDa420 from Thailand. In addition, from phylogenetic results based on the 16S rRNA gene and a concatenated tree of the 3 genes (gltA, ompA, and ompB), we found what may be a novel SFG rickettsia species closely related to Rickettsia raoultii (from both Amblyomma varanense and Amblyomma helvolum). In conclusion, our findings are the first report on the presence of novel SFG rickettsiae in 2 snake tick species, Amblyomma varanense and Amblyomma helvolum in Thailand and in south-eastern Asia.

  14. ABUNDANT OR RARE? A HYBRID APPROACH FOR DETERMINING SPECIES RELATIVE ABUNDANCE AT AN ECOREGOIONAL SCALE

    EPA Science Inventory

    Everyone knows what abundant and rare species are, but quantifying the concept proves elusive. As part of an EPA/USGS project to assess near-coastal species vulnerability to climate change affects, we designed a hybrid approach to determine species relative abundance at an ecoreg...

  15. ABUNDANT OR RARE? A HYBRID APPROACH FOR DETERMINING SPECIES RELATIVE ABUNDANCE AT AN ECOREGOIONAL SCALE - 2014

    EPA Science Inventory

    Everyone knows what abundant and rare species are, but quantifying the concept proves elusive. As part of an EPA/USGS project to assess near-coastal species vulnerability to climate change affects, we designed a hybrid approach to determine species relative abundance at an ecoreg...

  16. A cautionary note: survival of nymphs of two species of ticks (Acari: Ixodidae) among clothes laundered in an automatic washer.

    PubMed

    Carroll, J F

    2003-09-01

    Host-seeking ticks often remain on clothing of persons returning home from work or recreation in tick habitats, and can pose at least a temporary risk to people and pets in these homes. Laundering clothing has been one of the recommendations to reduce tick exposure. Host-seeking lone star tick, Amblyomma americanum (L.), and blacklegged tick, Ixodes scapularis Say, nymphs confined in polyester mesh packets, were included with laundry in cold, warm, and hot wash cycles of an automatic clothes washer. Ticks were also placed with washed clothing and subjected to drying in an automatic clothes dryer set on high heat and on air only (unheated). Most nymphs (> or = 90%) of both species survived the cold and warm washes, and 95% of A. americanum nymphs survived the hot wash. At the time of their removal from the washer, I. scapularis nymphs were clearly affected by the hot wash, but 65% were considered alive 20-24 h later. Large percentages of nymphs of both species survived hot washes in which two other detergents (a powder containing a nonchlorine bleach and a liquid) were used. All ticks were killed by the 1 h cycle at high heat in the clothes dryer, but with unheated air some nymphs of both species survived the 1 h cycle in the dryer. Given the laundering recommendations of clothing manufacturers and variation in the use automatic clothes washers, laundry washed in automatic washers should not be considered free of living ticks.

  17. Ticks infesting wild and domestic animals and humans of Sri Lanka with new host records.

    PubMed

    Liyanaarachchi, D R; Rajakaruna, R S; Dikkumbura, A W; Rajapakse, R P V J

    2015-02-01

    An island-wide collection of tick species infesting humans, domesticated and wild animals and questing ticks in domestic and peridomestic environments was carried out during 2009-2011. A total of 30,461 ticks were collected from 30 different hosts and free living stages from the ground. The collection consisted of 22 tick species from 30 different hosts recording 12 tick species from humans, 19 from domesticated animals and 21 from wild animals, with a total of 97 new host records. The most common tick species on humans were Dermacentor auratus and Amblyomma testudinairum, while Haemaphysalis intermedia, Rhipicephalus microplus and Rhipicephalus sanguineus were common in domesticated and wild animals sharing 20 host species. Among the questing ticks, immature D. auratus was the most abundant. Humans and domesticated animals were mostly infested by the nymphal stages while adult ticks were found on wild animals. High number of new host records could be due to domestic animals picking tick species from wildlife and vise versa at the human/animal interface. Habitat destruction due to forest fragmentation has lead to wild animals roaming in urban and semi-urban neighbourhoods increasing the interactions of wild animals with domesticated animals. Wild animals play a significant role as a reservoir of many tick borne infections which can easily be spread to domesticated animals and then to humans via tick infestations. Data in this paper are useful for those interested in tick infesting wild and domestic animals and humans in describing the zoonotic potential of tick borne infections.

  18. Phylogeny of a relapsing fever Borrelia species transmitted by the hard tick Ixodes scapularis.

    PubMed

    Barbour, Alan G

    2014-10-01

    The discovery of Borrelia species that were related to the agents of relapsing fever but were transmitted by hard ticks rather than soft ticks challenged previous taxonomies based largely on microbe-host specificities and geographic considerations. One of these newly-identified organisms is the Borrelia miyamotoi sensu lato strain LB-2001 from North America and transmitted by Ixodes scapularis. This or related strains have been identified as the cause of human disease, but comparatively little is known about their biology or genetics. Using recently acquired chromosome sequence of LB-2001 together with database sequences and additional sequences determined here, I carried out comparisons of the several species of Borrelia, including those in the two major clades: the relapsing fever group of species and the Lyme disease group of species. Phylogenetic inference at the species level was based on four data sets: whole chromosomes of ∼1Mb each, and concatenated sequences of 19 ribosomal protein genes, 3 conserved nucleic acid enzymes (rpoC, recC, and dnaE), and 4 contiguous genes for nucleotide salvage on a large plasmid. Analyses using neighbor-joining, maximum likelihood, and Bayesian methods were largely concordant for each of the trees. They showed that LB-2001 and related hard tick-associated organisms, like Borrelia lonestari, are deeply positioned within the RF group of species and that these organisms did not, as some earlier estimations had suggested, constitute a paraphyletic group. The analyses also provided further evidence that major changes in host ranges and life cycles, such as hard to soft ticks or vice versa, may not correlate well with overall sequence differences. The genetic differences between LB-2001 and B. miyamotoi sensu stricto justify provisional use of the "sensu lato" designation for LB-2001.

  19. Phylogeny of a relapsing fever Borrelia species transmitted by the hard tick Ixodes scapularis

    PubMed Central

    Barbour, Alan G.

    2014-01-01

    The discovery of Borrelia species that were related to the agents of relapsing fever but were transmitted by hard ticks rather than soft ticks challenged previous taxonomies based largely on microbe-host specificities and geographic considerations. One of these newly-identified organisms is the Borrelia miyamotoi sensu lato strain LB-2001 from North America and transmitted by Ixodes scapularis. This or related strains have been identified as the cause of human disease, but comparatively little is known about their biology or genetics. Using recently acquired chromosome sequence of LB-2001 together with database sequences and additional sequences determined here, I carried out comparisons of the several species of Borrelia, including those in the two major clades: the relapsing fever group of species and the Lyme disease group of species. Phylogenetic inference at the species level was based on four data sets: whole chromosomes of ~1 Mb each, and concatenated sequences of 19 ribosomal protein genes, 3 conserved nucleic acid enzymes (rpoC, recC, and dnaE), and 4 contiguous genes for nucleotide salvage on a large plasmid. Analyses using neighbor-joining, maximum likelihood, and Bayesian methods were largely concordant for each of the trees. They showed that LB-2001 and related hard tick-associated organisms, like B. lonestari, are deeply positioned within the RF group of species and that these organisms did not, as some earlier estimations had suggested, constitute a paraphyletic group. The analyses also provided further evidence that major changes in host ranges and life cycles, such as hard to soft ticks or vice versa, may not correlate well with overall sequence differences. The genetic differences between LB-2001 and B. miyamotoi sensu stricto justify provisional use of the “sensu lato” designation for LB-2001. PMID:24813576

  20. Predicted correspondence between species abundances and dendrograms of niche similarities

    PubMed Central

    Sugihara, George; Bersier, Louis-Félix; Southwood, T. Richard E.; Pimm, Stuart L.; May, Robert M.

    2003-01-01

    We examine a hypothesized relationship between two descriptions of community structure: the niche-overlap dendrogram that describes the ecological similarities of species and the pattern of relative abundances. Specifically, we examine the way in which this relationship follows from the niche hierarchy model, whose fundamental assumption is a direct connection between abundances and underlying hierarchical community organization. We test three important, although correlated, predictions of the niche hierarchy model and show that they are upheld in a set of 11 communities (encompassing fishes, amphibians, lizards, and birds) where both abundances and dendrograms were reported. First, species that are highly nested in the dendrogram are on average less abundant than species from branches less subdivided. Second, and more significantly, more equitable community abundances are associated with more evenly branched dendrogram structures, whereas less equitable abundances are associated with less even dendrograms. This relationship shows that abundance patterns can give insight into less visible aspects of community organization. Third, one can recover the distribution of proportional abundances seen in assemblages containing two species by treating each branch point in the dendrogram as a two-species case. This reconstruction cannot be achieved if abundances and the dendrogram are unrelated and suggests a method for hierarchically decomposing systems. To our knowledge, this is the first test of a species abundance model based on nontrivial predictions as to the origins and causes of abundance patterns, and not simply on the goodness-of-fit of distributions. PMID:12702773

  1. Factors Driving the Abundance of Ixodes ricinus Ticks and the Prevalence of Zoonotic I. ricinus-Borne Pathogens in Natural Foci

    PubMed Central

    Fernández-de-Mera, Isabel G.; Acevedo, Pelayo; Gortázar, Christian; de la Fuente, José

    2012-01-01

    Environmental factors may drive tick ecology and therefore tick-borne pathogen (TBP) epidemiology, which determines the risk to animals and humans of becoming infected by TBPs. For this reason, the aim of this study was to analyze the influence of environmental factors on the abundance of immature-stage Ixodes ricinus ticks and on the prevalence of two zoonotic I. ricinus-borne pathogens in natural foci of endemicity. I. ricinus abundance was measured at nine sites in the northern Iberian Peninsula by dragging the vegetation with a cotton flannelette, and ungulate abundance was measured by means of dung counts. In addition to ungulate abundance, data on variables related to spatial location, climate, and soil were gathered from the study sites. I. ricinus adults, nymphs, and larvae were collected from the vegetation, and a representative subsample of I. ricinus nymphs from each study site was analyzed by PCR for the detection of Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum DNA. Mean prevalences of these pathogens were 4.0% ± 1.8% and 20.5% ± 3.7%, respectively. Statistical analyses confirmed the influence of spatial factors, climate, and ungulate abundance on I. ricinus larva abundance, while nymph abundance was related only to climate. Interestingly, cattle abundance rather than deer abundance was the main driver of B. burgdorferi sensu lato and A. phagocytophilum prevalence in I. ricinus nymphs in the study sites, where both domestic and wild ungulates coexist. The increasing abundance of cattle seems to increase the risk of other hosts becoming infected by A. phagocytophilum, while reducing the risk of being infected by B. burgdorferi sensu lato. Controlling ticks in cattle in areas where they coexist with wild ungulates would be more effective for TBP control than reducing ungulate abundance. PMID:22286986

  2. Geographical range and local abundance of tree species in China.

    PubMed

    Ren, Haibao; Condit, Richard; Chen, Bin; Mi, Xiangcheng; Cao, Min; Ye, Wanhui; Hao, Zhanqing; Ma, Keping

    2013-01-01

    Most studies on the geographical distribution of species have utilized a few well-known taxa in Europe and North America, with little research in China and its wide range of climate and forest types. We assembled large datasets to quantify the geographic ranges of tree species in China and to test several biogeographic hypotheses: 1) whether locally abundant species tend to be geographically widespread; 2) whether species are more abundant towards their range-centers; and 3) how abundances are correlated between sites. Local abundances of 651 species were derived from four tree plots of 20-25 ha where all individuals ≥1 cm in stem diameter were mapped and identified taxonomically. Range sizes of these species across China were then estimated from over 460,000 geo-referenced records; a Bayesian approach was used, allowing careful measures of error of each range estimate. The log-transformed range sizes had a bell-shaped distribution with a median of 703,000 km(2), and >90% of 651 species had ranges >10(5) km(2). There was no relationship between local abundance and range size, and no evidence for species being more abundant towards their range-centers. Finally, species' abundances were positively correlated between sites. The widespread nature of most tree species in China suggests few are vulnerable to global extinction, and there is no indication of the double-peril that would result if rare species also had narrow ranges.

  3. Geographical Range and Local Abundance of Tree Species in China

    PubMed Central

    Ren, Haibao; Condit, Richard; Chen, Bin; Mi, Xiangcheng; Cao, Min; Ye, Wanhui; Hao, Zhanqing; Ma, Keping

    2013-01-01

    Most studies on the geographical distribution of species have utilized a few well-known taxa in Europe and North America, with little research in China and its wide range of climate and forest types. We assembled large datasets to quantify the geographic ranges of tree species in China and to test several biogeographic hypotheses: 1) whether locally abundant species tend to be geographically widespread; 2) whether species are more abundant towards their range-centers; and 3) how abundances are correlated between sites. Local abundances of 651 species were derived from four tree plots of 20–25 ha where all individuals ≥1 cm in stem diameter were mapped and identified taxonomically. Range sizes of these species across China were then estimated from over 460,000 geo-referenced records; a Bayesian approach was used, allowing careful measures of error of each range estimate. The log-transformed range sizes had a bell-shaped distribution with a median of 703,000 km2, and >90% of 651 species had ranges >105 km2. There was no relationship between local abundance and range size, and no evidence for species being more abundant towards their range-centers. Finally, species’ abundances were positively correlated between sites. The widespread nature of most tree species in China suggests few are vulnerable to global extinction, and there is no indication of the double-peril that would result if rare species also had narrow ranges. PMID:24130772

  4. Model reduction for stochastic chemical systems with abundant species.

    PubMed

    Smith, Stephen; Cianci, Claudia; Grima, Ramon

    2015-12-07

    Biochemical processes typically involve many chemical species, some in abundance and some in low molecule numbers. We first identify the rate constant limits under which the concentrations of a given set of species will tend to infinity (the abundant species) while the concentrations of all other species remains constant (the non-abundant species). Subsequently, we prove that, in this limit, the fluctuations in the molecule numbers of non-abundant species are accurately described by a hybrid stochastic description consisting of a chemical master equation coupled to deterministic rate equations. This is a reduced description when compared to the conventional chemical master equation which describes the fluctuations in both abundant and non-abundant species. We show that the reduced master equation can be solved exactly for a number of biochemical networks involving gene expression and enzyme catalysis, whose conventional chemical master equation description is analytically impenetrable. We use the linear noise approximation to obtain approximate expressions for the difference between the variance of fluctuations in the non-abundant species as predicted by the hybrid approach and by the conventional chemical master equation. Furthermore, we show that surprisingly, irrespective of any separation in the mean molecule numbers of various species, the conventional and hybrid master equations exactly agree for a class of chemical systems.

  5. Model reduction for stochastic chemical systems with abundant species

    SciTech Connect

    Smith, Stephen; Cianci, Claudia; Grima, Ramon

    2015-12-07

    Biochemical processes typically involve many chemical species, some in abundance and some in low molecule numbers. We first identify the rate constant limits under which the concentrations of a given set of species will tend to infinity (the abundant species) while the concentrations of all other species remains constant (the non-abundant species). Subsequently, we prove that, in this limit, the fluctuations in the molecule numbers of non-abundant species are accurately described by a hybrid stochastic description consisting of a chemical master equation coupled to deterministic rate equations. This is a reduced description when compared to the conventional chemical master equation which describes the fluctuations in both abundant and non-abundant species. We show that the reduced master equation can be solved exactly for a number of biochemical networks involving gene expression and enzyme catalysis, whose conventional chemical master equation description is analytically impenetrable. We use the linear noise approximation to obtain approximate expressions for the difference between the variance of fluctuations in the non-abundant species as predicted by the hybrid approach and by the conventional chemical master equation. Furthermore, we show that surprisingly, irrespective of any separation in the mean molecule numbers of various species, the conventional and hybrid master equations exactly agree for a class of chemical systems.

  6. Diversity and seasonal patterns of ticks parasitizing wild birds in western Portugal.

    PubMed

    Norte, A C; de Carvalho, I Lopes; Ramos, J A; Gonçalves, M; Gern, L; Núncio, M S

    2012-11-01

    The diversity and abundance of questing ticks and ticks parasitizing birds was assessed during 1 year in two recreational forests in western Portugal, a suburban forest and an enclosed game area. The aim of this study was to assess the distribution and seasonality of tick species and to understand the role of bird species as hosts for ticks. Ixodes ricinus was the most abundant questing tick collected in the enclosed game area, whereas in the suburban forest, only three ticks were collected by blanket dragging. Tick species parasitizing birds included I. ricinus, I. frontalis, I. arboricola, I. acuminatus, Haemaphysalis punctata, Hyalomma marginatum and H. lusitanicum. This is the first record of I. arboricola in Portugal. Tick prevalence and intensity of infestation differed between study areas and was higher in birds from the game area where a large population of deer and wild boar may support tick populations. Ground and shrub dwelling bird species such as Turdus merula, Erithacus rubecula and Sylvia melanocephala were the most heavily parasitized by ticks, but the importance of different bird species as hosts of larvae and nymphs of I. ricinus and I. frontalis differed. Therefore, different bird species may contribute differently for tick population maintenance.

  7. Ecological niche structure and rangewide abundance patterns of species

    PubMed Central

    Martínez-Meyer, Enrique; Díaz-Porras, Daniel; Peterson, A. Townsend; Yáñez-Arenas, Carlos

    2013-01-01

    Spatial abundance patterns across species' ranges have attracted intense attention in macroecology and biogeography. One key hypothesis has been that abundance declines with geographical distance from the range centre, but tests of this idea have shown that the effect may occur indeed only in a minority of cases. We explore an alternative hypothesis: that species' abundances decline with distance from the centroid of the species' habitable conditions in environmental space (the ecological niche). We demonstrate consistent negative abundance–ecological distance relationships across all 11 species analysed (turtles to wolves), and that relationships in environmental space are consistently stronger than relationships in geographical space. PMID:23134784

  8. Efficiency of flagging and dragging for tick collection.

    PubMed

    Dantas-Torres, Filipe; Lia, Riccardo Paolo; Capelli, Gioia; Otranto, Domenico

    2013-09-01

    It is acknowledged that data from field studies on tick ecology might be biased by collection methods, but actually comparative studies are still limited. Herein we assessed whether the efficiency of flagging and dragging varies according to tick developmental stage, species, season and habitat. Ticks were collected in three sites bordered by an oak forest. The abundance of ticks collected by each collection method varied according to tick species, developmental stage, season, and habitat. Flagging was in general more efficient in collecting adult ticks, especially in spring and winter. Females were more frequently collected by flagging in the meadow and grassland habitats and males in the man-made trail. Flagging collected significantly more adults of Dermacentor marginatus, Hyalomma marginatum, Haemaphysalis inermis and Ixodes ricinus. Flagging was more efficient in collecting D. marginatus and I. ricinus in spring, and H. inermis and I. ricinus females in both spring and winter. In summer and autumn tick abundances were generally similar, with the exception of D. marginatus female in autumn. Flagging was more efficient in collecting D. marginatus adults in the meadow habitat and in the man-made trail, and I. ricinus adults in the meadow and grassland habitats. Dragging was more efficient in grassland for R. turanicus. Our results suggest that variations in terms of collection method performance are associated to factors linked to tick behaviour, habitat characteristics, and climate. Field studies employing these collection methods should take this into account to avoid misleading conclusions about tick population dynamics and tick-borne pathogen transmission risk.

  9. Why abundant tropical tree species are phylogenetically old.

    PubMed

    Wang, Shaopeng; Chen, Anping; Fang, Jingyun; Pacala, Stephen W

    2013-10-01

    Neutral models of species diversity predict patterns of abundance for communities in which all individuals are ecologically equivalent. These models were originally developed for Panamanian trees and successfully reproduce observed distributions of abundance. Neutral models also make macroevolutionary predictions that have rarely been evaluated or tested. Here we show that neutral models predict a humped or flat relationship between species age and population size. In contrast, ages and abundances of tree species in the Panamanian Canal watershed are found to be positively correlated, which falsifies the models. Speciation rates vary among phylogenetic lineages and are partially heritable from mother to daughter species. Variable speciation rates in an otherwise neutral model lead to a demographic advantage for species with low speciation rate. This demographic advantage results in a positive correlation between species age and abundance, as found in the Panamanian tropical forest community.

  10. Effect of attractant sex pheromone on immature larval stages of ixodid tick species.

    PubMed

    Ranju, R S; Latha, Bhaskaran Ravi; Leela, V; Basith, S Abdul

    2012-10-01

    Attractant sex pheromone (ASP) 2,6-dichloro phenol was used in the current study to evaluate the percentage attraction and the behavioural responses of the five ixodid tick species namely Rhipicephalus sanguineus, Rhipicephalus microplus (Boophilus microplus), Haemaphysalis bispinosa, Rhipicephalus haemaphysaloides and Hyalomma marginatum using petridish bioassay. Two concentrations of 2,6-DCP (0.1 M and 0.05 M) was used for the larval stages of all five ixodid tick species of which 0.1 M concentration was found to have maximum attraction. Trials with 0.1 M ASP revealed highest per cent of attraction in R. sanguineus larvae (71 %) followed by H. bispinosa (55 %) and R. microplus (55 %). With 0.1 M ASP R. haemaphysaloides and H. marginatum showed least attraction (39 % each). However the per cent of attraction of R. haemaphysaloides was higher (46 %) with 0.05 M ASP. Statistical analysis revealed a highly significant difference in per cent of attraction between the different tick larvae using 0.05 and 0.1 M ASP. The larvae also exhibited behavioural responses such as feeding, probing, resting and questing posture.

  11. Midichloria mitochondrii is widespread in hard ticks (Ixodidae) and resides in the mitochondria of phylogenetically diverse species.

    PubMed

    Epis, S; Sassera, D; Beninati, T; Lo, N; Beati, L; Piesman, J; Rinaldi, L; McCoy, K D; Torina, A; Sacchi, L; Clementi, E; Genchi, M; Magnino, S; Bandi, C

    2008-04-01

    The hard tick Ixodes ricinus (Ixodidae) is the sole animal thus far shown to harbour an intra-mitochondrial bacterium, which has recently been named Midichloria mitochondrii. The objectives of this work were (i) to screen ixodid ticks for Midichloria-related bacteria and (ii) to determine whether these bacteria exploit the intra-mitochondrial niche in other tick species. Our main goal was to discover further models of this peculiar form of symbiosis. We have thus performed a PCR screening for Midichloria-related bacteria in samples of ixodid ticks collected in Italy, North America and Iceland. A total of 7 newly examined species from 5 genera were found positive for bacteria closely related to M. mitochondrii. Samples of the tick species Rhipicephalus bursa, found positive in the PCR screening, were analysed with transmission electron microscopy, which revealed the presence of bacteria both in the cytoplasm and in the mitochondria of the oocytes. There is thus evidence that bacteria invade mitochondria in at least 2 tick species. Phylogenetic analysis on the bacterial 16S rRNA gene sequences generated from positive specimens revealed that the bacteria form a monophyletic group within the order Rickettsiales. The phylogeny of Midichloria symbionts and related bacteria does not appear completely congruent with the phylogeny of the hosts.

  12. Comparative population dynamics of a generalist (Ixodes ricinus) and specialist tick (I. hexagonus) species from European hedgehogs.

    PubMed

    Pfäffle, M; Petney, T; Skuballa, J; Taraschewski, H

    2011-06-01

    Although the population dynamics of the tick Ixodes ricinus are relatively well studied, those of other Western European tick species are largely unknown. Moreover, there is very little information related to the interactions between I. ricinus and other ticks. Such knowledge, however, is of special interest in respect to the epidemiology of tick-borne pathogens such as Borrelia spp. We compared the dynamics of the generalist I. ricinus with the nest-dwelling hedgehog specialist, I. hexagonus. Both species were collected from hedgehogs from a naturally infested experimental population between 2006 and 2008. Ticks were collected once a month from March to October from each hedgehog counted and the life history stage and species determined. All hedgehogs harboured both tick species. Nymphs, females and males of I. ricinus showed clear bimodal seasonal distributions with peaks in spring and autumn, while larvae peaked only in summer. The density of I. hexagonus life stages was low during the whole investigation period and seasonal fluctuations of population density were much weaker compared to I. ricinus. Nymphs and larvae showed comparatively little change in population size and no consistent period of peak density. Females showed a single peak in summer and males were found only occasionally on hedgehogs. We suggest density-dependent mechanisms regulating the population density of the specialist I. hexagonus but not of the generalist I. ricinus.

  13. The decoupling of abundance and species richness in lizard communities.

    PubMed

    Nimmo, Dale G; James, Simon G; Kelly, Luke T; Watson, Simon J; Bennett, Andrew F

    2011-05-01

    1. Patterns of species richness often correlate strongly with measures of energy. The more individuals hypothesis (MIH) proposes that this relationship is facilitated by greater resources supporting larger populations, which are less likely to become extinct. Hence, the MIH predicts that community abundance and species richness will be positively related. 2. Recently, Buckley & Jetz (2010, Journal of Animal Ecology, 79, 358-365) documented a decoupling of community abundance and species richness in lizard communities in south-west United States, such that richer communities did not contain more individuals. They predicted, as a consequence of the mechanisms driving the decoupling, a more even distribution of species abundances in species-rich communities, evidenced by a positive relationship between species evenness and species richness. 3. We found a similar decoupling of the relationship between abundance and species richness for lizard communities in semi-arid south-eastern Australia. However, we note that a positive relationship between evenness and richness is expected because of the nature of the indices used. We illustrate this mathematically and empirically using data from both sets of lizard communities. When we used a measure of evenness, which is robust to species richness, there was no relationship between evenness and richness in either data set. 4. For lizard communities in both Australia and the United States, species dominance decreased as species richness increased. Further, with the iterative removal of the first, second and third most dominant species from each community, the relationship between abundance and species richness became increasingly more positive. 5. Our data support the contention that species richness in lizard communities is not directly related to the number of individuals an environment can support. We propose an alternative hypothesis regarding how the decoupling of abundance and richness is accommodated; namely, an inverse

  14. Molecular and morphological description of a Hepatozoon species in reptiles and their ticks in the Northern Territory, Australia.

    PubMed

    Vilcins, Inger-Marie E; Ujvari, Beata; Old, Julie M; Deane, Elizabeth

    2009-04-01

    Ticks, representing 3 species of Amblyomma, were collected from the water python (Liasis fuscus) and 3 additional reptile species in the Northern Territory, Australia, and tested for the presence of Hepatozoon sp., the most common blood parasites of snakes. In addition, blood smears were collected from 5 reptiles, including the water python, and examined for the presence of the parasite. Hepatozoon sp. DNA was detected in all tick and reptile species, with 57.7% of tick samples (n = 187) and 35.6% of blood smears (n=35) showing evidence of infection. Phylogenetic analysis of the 18S rRNA gene demonstrated that half of the sequences obtained from positive tick samples matched closest with a Hepatozoon species previously identified in the water python population. The remaining sequences were found to be more closely related to mammalian and amphibian Hepatozoon species. This study confirms that species of Amblyomma harbor DNA of the same Hepatozoon species detected in the water pythons. The detection of an additional genotype suggests the ticks may be exposed to 2 Hepatozoon species, providing further opportunity to study multiple host-vector-parasite relationships.

  15. Multiple peaks of species abundance distributions induced by sparse interactions

    NASA Astrophysics Data System (ADS)

    Obuchi, Tomoyuki; Kabashima, Yoshiyuki; Tokita, Kei

    2016-08-01

    We investigate the replicator dynamics with "sparse" symmetric interactions which represent specialist-specialist interactions in ecological communities. By considering a large self-interaction u , we conduct a perturbative expansion which manifests that the nature of the interactions has a direct impact on the species abundance distribution. The central results are all species coexistence in a realistic range of the model parameters and that a certain discrete nature of the interactions induces multiple peaks in the species abundance distribution, providing the possibility of theoretically explaining multiple peaks observed in various field studies. To get more quantitative information, we also construct a non-perturbative theory which becomes exact on tree-like networks if all the species coexist, providing exact critical values of u below which extinct species emerge. Numerical simulations in various different situations are conducted and they clarify the robustness of the presented mechanism of all species coexistence and multiple peaks in the species abundance distributions.

  16. Ticks and spotted fever group rickettsiae of southeastern Virginia.

    PubMed

    Nadolny, Robyn M; Wright, Chelsea L; Sonenshine, Daniel E; Hynes, Wayne L; Gaff, Holly D

    2014-02-01

    The incidence of tick-borne rickettsial disease in the southeastern United States has been rising steadily through the past decade, and the range expansions of tick species and tick-borne infectious agents, new and old, has resulted in an unprecedented mix of vectors and pathogens. The results of an ongoing 4-year surveillance project describe the relative abundance of questing tick populations in southeastern Virginia. Since 2009, more than 66,000 questing ticks of 7 species have been collected from vegetation in a variety of habitats, with Amblyomma americanum constituting over 95% of ticks collected. Other species represented included Ixodes scapularis, Dermacentor variabilis, Amblyomma maculatum, Ixodes affinis, Haemaphysalis leporispalustris, and Ixodes brunneus. We found that 26.9-54.9% of A. americanum ticks tested were positive for Rickettsia amblyommii, a non-pathogenic symbiont of this tick species. We also found no evidence of R. rickettsii in D. variabilis ticks, although they did show low infection rates of R. montanensis (1.5-2.0%). Rickettsia parkeri and Candidatus R. andeanae were found in 41.8-55.7% and 0-1.5% A. maculatum ticks, respectively. The rate of R. parkeri in A. maculatum ticks is among the highest in the literature and has increased in the 2 years since R. parkeri and A. maculatum were first reported in southeastern Virginia. We conclude that tick populations in southeastern Virginia have recently undergone dramatic changes in species and abundance and that these populations support a variety of rickettsial agents with the potential for increased risk to human health.

  17. Evaluation of the efficacy of afoxolaner against two European dog tick species: Dermacentor reticulatus and Ixodes ricinus.

    PubMed

    Dumont, Pascal; Blair, Jeffrey; Fourie, Josephus J; Chester, Theodore S; Larsen, Diane L

    2014-04-02

    The acaricidal efficacy of a novel oral formulation of afoxolaner (NEXGARD(®), Merial) against two European tick species was assessed in dogs experimentally infested with Ixodes ricinus and Dermacentor reticulatus. Three studies, each characterized by a negative controlled randomized block design, were conducted with a total of 52 beagle or mongrel dogs of both sexes. Starting 2 days before treatment, each dog was infested weekly with approximately 50 ticks. The number of live ticks was counted at 48 h post-treatment (Day 2) as well as 48 h following each infestation on Days 9, 16, 23, and 30. Afoxolaner, administered at an average dose of 2.7 mg/kg bodyweight (range 2.5-2.9 mg/kg), rapidly eliminated the pre-existing tick infestations with over 99% acaricidal efficacy and controlled the weekly re-infestations for up to 30 days post treatment with over 96% efficacy on both tick species. Afoxolaner provides excellent acaricidal efficacy against these two major European tick species using the oral route of administration.

  18. Serologic and molecular characterization of Anaplasma species infection in farm animals and ticks from Sicily.

    PubMed

    de la Fuente, José; Torina, Alessandra; Caracappa, Santo; Tumino, Giovanni; Furlá, Roberto; Almazán, Consuelo; Kocan, Katherine M

    2005-11-05

    Although Anaplasma marginale was known to be endemic in Italy, the diversity of Anaplasma spp. from this area have not been characterized. In this study, the prevalence of Anaplasma spp. antibodies in randomly selected farm animals collected on the island of Sicily was determined by use of a MSP5 cELISA for Anaplasma spp. and an immunofluorescence test specific for Anaplasma phagocytophilum. Genetic variation among strains of Anaplasma spp. from animals and ticks was characterized using the A. marginale msp1alpha and the Anaplasma spp. msp4 genes. Eight species of ticks were collected and tested by PCR. Seropositivity for Anaplasma spp. and A. phagocytophilum was detected in bovine and ovine samples. All the donkeys were seropositive for A. phagocytophilum but not for Anaplasma spp. Four A. marginale genotypes were identified by msp4 sequences from bovine and tick samples. Two new genotypes of Anaplasma ovis were characterized in sheep. The sequences of A. phagocytophilum from three donkeys proved to be identical to the sequence of the MRK equine isolate from California. Six A. marginale genotypes were found in cattle and one tick using the A. marginale msp1alpha sequences. All genotypes had four repeated sequences in the N-terminal portion of the MSP1a, except for one that had five repeats. The Italian strains of A. marginale contained three repeat sequences that were not reported previously. Definition of the diversity of Anaplasma spp. in Sicily reported, herein is fundamental to development of control strategies for A. marginale, A. ovis and A. phagocytophilum in Sicily.

  19. Tick infestation on wild snakes in northern part of western Ghats of India.

    PubMed

    Pandit, Pranav; Bandivdekar, Ruta; Geevarghese, G; Pande, Satish; Mandke, Omkar

    2011-05-01

    In total, 167 individuals of 30 species of snakes belonging to 22 genera and five families were examined for tick infestation from November 2008 to March 2010. Only two species of snakes, Ptyas mucosa (L., 1758) (Indian rat snake) and Naja naja (L., 1758) (spectacled cobra), were found infested by ticks. All ticks collected were identified to be Amblyomma gervaisi [previously Aponomma gervaisi (Lucas, 1847) 1. The average prevalence of these ticks on Indian rat snakes (n=48) was 29.16%, with abundance of 7.02 ticks per individual; on spectacled cobras (n=20), average prevalence was 30.00%, with abundance of 6.9 ticks per individual. The nymphs and males were predominant. All the ticks were found on the dorsal aspect of the body of the snake, and no ticks were recorded on the head, tail, or ventral body. The rate of tick infestation was highest in scrubland and was lowest in evergreen forests. Female Indian rat snakes showed higher tick infestation rates than male Indian rat snakes. Using Mann-Whitney U test, we found that longer snakes of both species had significantly higher rate of tick infestation in both the species of snakes.

  20. Tick paralysis in Australia caused by Ixodes holocyclus Neumann

    PubMed Central

    Hall-Mendelin, S; Craig, S B; Hall, R A; O’Donoghue, P; Atwell, R B; Tulsiani, S M; Graham, G C

    2011-01-01

    Ticks are obligate haematophagous ectoparasites of various animals, including humans, and are abundant in temperate and tropical zones around the world. They are the most important vectors for the pathogens causing disease in livestock and second only to mosquitoes as vectors of pathogens causing human disease. Ticks are formidable arachnids, capable of not only transmitting the pathogens involved in some infectious diseases but also of inducing allergies and causing toxicoses and paralysis, with possible fatal outcomes for the host. This review focuses on tick paralysis, the role of the Australian paralysis tick Ixodes holocyclus, and the role of toxin molecules from this species in causing paralysis in the host. PMID:21396246

  1. A quantitative synthesis of the role of birds in carrying ticks and tick-borne pathogens in North America.

    PubMed

    Loss, Scott R; Noden, Bruce H; Hamer, Gabriel L; Hamer, Sarah A

    2016-12-01

    Birds play a central role in the ecology of tick-borne pathogens. They expand tick populations and pathogens across vast distances and serve as reservoirs that maintain and amplify transmission locally. Research into the role of birds for supporting ticks and tick-borne pathogens has largely been descriptive and focused in small areas. To expand inference beyond these studies, we conducted a quantitative review at the scale of North America to identify avian life history correlates of tick infestation and pathogen prevalence, calculate species-level indices of importance for carrying ticks, and identify research gaps limiting understanding of tick-borne pathogen transmission. Across studies, 78 of 162 bird species harbored ticks, yielding an infestation prevalence of 1981 of 38,929 birds (5.1 %). Avian foraging and migratory strategies interacted to influence infestation. Ground-foraging species, especially non-migratory ground foragers, were disproportionately likely to have high prevalence and intensity of tick infestation. Studies largely focused on Borrelia burgdorferi, the agent of Lyme disease, and non-migratory ground foragers were especially likely to carry B. burgdorferi-infected ticks, a finding that highlights the potential importance of resident birds in local pathogen transmission. Based on infestation indices, all "super-carrier" bird species were passerines. Vast interior areas of North America, many bird and tick species, and most tick-borne pathogens, remain understudied, and research is needed to address these gaps. More studies are needed that quantify tick host preferences, host competence, and spatiotemporal variation in pathogen prevalence and vector and host abundance. This information is crucial for predicting pathogen transmission dynamics under future global change.

  2. Larval keys to the genera of Ixodidae (Acari) and species of Ixodes (Latreille) ticks established in California

    PubMed Central

    Kleinjan, Joyce E.; Lane, Robert S.

    2009-01-01

    In California, hard (Ixodidae) ticks transmit at least 8 zoonotic disease agents (1 virus, 6 bacteria, 1 protozoan) to humans or other animals. The correct taxonomic identification of all 3 parasitic stages (larvae, nymphs, adults) of ticks is integral to understanding host-tick associations and disease dynamics, but immature ticks, especially the larvae, can be difficult to identify. Here, we present larval keys to the 4 genera of Ixodidae (Dermacentor Koch, 1844; Haemaphysalis Koch, 1844; Ixodes Latreille, 1795; Rhipicephalus Koch, 1844) and to the 18 species of Ixodes known to be established in California. Several new diagnostic features, as well as photographs of microscopic structures, are provided to facilitate identification. Non-exclusive characters are utilized to separate the subgenera Ixodiopsis Filippova, 1957 and Pholeoixodes Schulze, 1942. PMID:20027236

  3. Bacterial Profiling Reveals Novel “Ca. Neoehrlichia”, Ehrlichia, and Anaplasma Species in Australian Human-Biting Ticks

    PubMed Central

    Gofton, Alexander W.; Doggett, Stephen; Ratchford, Andrew; Oskam, Charlotte L.; Paparini, Andrea; Ryan, Una; Irwin, Peter

    2015-01-01

    In Australia, a conclusive aetiology of Lyme disease-like illness in human patients remains elusive, despite growing numbers of people presenting with symptoms attributed to tick bites. In the present study, we surveyed the microbial communities harboured by human-biting ticks from across Australia to identify bacteria that may contribute to this syndrome. Universal PCR primers were used to amplify the V1-2 hyper-variable region of bacterial 16S rRNA genes in DNA samples from individual Ixodes holocyclus (n = 279), Amblyomma triguttatum (n = 167), Haemaphysalis bancrofti (n = 7), and H. longicornis (n = 7) ticks. The 16S amplicons were sequenced on the Illumina MiSeq platform and analysed in USEARCH, QIIME, and BLAST to assign genus and species-level taxonomies. Nested PCR and Sanger sequencing were used to confirm the NGS data and further analyse novel findings. All 460 ticks were negative for Borrelia spp. by both NGS and nested PCR analysis. Two novel “Candidatus Neoehrlichia” spp. were identified in 12.9% of I. holocyclus ticks. A novel Anaplasma sp. was identified in 1.8% of A. triguttatum ticks, and a novel Ehrlichia sp. was identified in both A. triguttatum (1.2%) ticks and a single I. holocyclus (0.6%) tick. Further phylogenetic analysis of novel “Ca. Neoehrlichia”, Anaplasma and Ehrlichia based on 1,265 bp 16S rRNA gene sequences suggests that these are new species. Determining whether these newly discovered organisms cause disease in humans and animals, like closely related bacteria do abroad, is of public health importance and requires further investigation. PMID:26709826

  4. Ticks collected from migratory birds, including a new record of Haemaphysalis formosensis, on Jeju Island, Korea.

    PubMed

    Choi, Chang-Yong; Kang, Chang-Wan; Kim, Eun-Mi; Lee, Sang; Moon, Kyoung-Ha; Oh, Mi-Rae; Yamauchi, Takeo; Yun, Young-Min

    2014-04-01

    Migratory birds may disperse parasites across ecological barriers, and recent climate change may alter the pattern of ectoparasite dispersal via changed patterns of bird migration. In order to document the parasitization of migratory birds by Ixodidae ticks on Jeju Island in Korea, we examined 934 migratory birds comprising 75 species for ticks from 2010 to 2012. In total, 313 ticks were collected from 74 migratory birds across 17 avian species and identified based on morphological keys. These ticks represented six species: Haemaphysalis flava, H. formosensis, H. longicornis, H. concinna, Ixodes turdus and I. nipponensis. Of particular note was the presence of H. formosensis, a species not previously reported to have been found in Korea, and H. concinna, which had not been previously reported on Jeju Island. The dominant tick species found were H. flava (226 ticks, 72.2 %) and I. turdus (54 ticks, 17.3 %), and ground-dwelling thrushes such as Pale thrushes (Turdus pallidus; 39 birds, 52.7 %) were the most important hosts. Although H. longicornis is the most abundant and prevalent terrestrial tick on Jeju Island, the species accounted for only 3.8 % of the total ticks collected in this study, suggesting that ticks on migratory birds may differ from the local tick fauna and that exotic ticks may be introduced via migratory birds. Therefore, long-term programs for tick and tick-borne disease surveillance are recommended to understand the role of migratory animals in the introduction of exotic species and associated pathogens and in life cycles of ticks at different stages in this region.

  5. Improved molecular detection of Ehrlichia and Anaplasma species applied to Amblyomma ticks collected from cattle and sheep in Ethiopia.

    PubMed

    Teshale, S; Geysen, D; Ameni, G; Asfaw, Y; Berkvens, D

    2015-02-01

    Detection of Ehrlichia and Anaplasma species in animals and tick vectors is crucial for an understanding of the epidemiology of diseases caused by these pathogens. In this study, a pair of primers designated EBR2 and EBR3 was designed from the Anaplasma 16S rDNA sequence and was used along with a previously described primer EHR 16SD for the simultaneous detection of Ehrlichia and Anaplasma species by nested PCR. The primers were used to amplify 925bp of DNA from known species of Ehrlichia and Anaplasma. Restriction with MboII and MspI enzymes allowed Ehrlichia and Anaplasma speciation. Restriction with MboII differentiated between An. marginale, Anaplasma (formerly Ehrlichia) sp. Omatjenne, and An. centrale with An. marginale and Anaplasma (formerly Ehrlichia) sp. Omatjenne yielding 2 distinct fragments each while An. centrale produced 3 distinct bands. Ehrlichia ruminantium and An. phagocytophylum remained undigested. Subsequent restriction with MspI differentiated E. ruminantium from An. phagocytophylum with 2 and 4 fragments, respectively. When used on tick samples from the field, 63 ticks (16.4%) out of 384 collected from cattle and sheep were positive for one or more species of Ehrlichia and Anaplasma. The positivity ranged from 6.3% at Andasa to 36.7% at Habernosa. Higher overall infection rates were found in Amblyomma lepidum than in Amblyomma variegatum ticks (p=0.009). Amblyomma lepidum from Habernosa were more often infected with all detected species of Anaplasma and Ehrlichia than Am. variegatum. At Bako, however, Anaplasma (formerly Ehrlichia) sp. Omatjenne was detected only in Am. variegatum. A significantly higher proportion of ticks collected from cattle (20.6%) was found positive than in those collected from sheep (3.3%) (p=0.003). Simultaneous detection of Ehrlichia and Anaplasma species and correct identification of mixed infections was possible. Since the ticks were collected from animals, the occurrence of the major species of Ehrlichia and

  6. Capybaras and ticks in the urban areas of Uberlândia, Minas Gerais, Brazil: ecological aspects for the epidemiology of tick-borne diseases.

    PubMed

    Queirogas, V L; Del Claro, K; Nascimento, A R T; Szabó, M P J

    2012-05-01

    In Brazil capybara, the biggest existing rodent species, and associated tick species, Amblyomma cajennense and Amblyomma dubitatum, are undergoing an unplanned host and parasite population expansion in both urban and rural areas. However, scientific information about such issue, particularly in urban areas, is scanty. Such rodent and ticks are associated in some municipalities, particularly in southeastern Brazil, with the transmission of the highly lethal Rickettsia rickettsia caused spotted-fever. In this study ecological aspects related to the establishment and expansion of capybaras and ticks in urban areas of Uberlândia, Minas Gerais State, Brazil were evaluated. For this purpose, capybara and tick abundance in four urban areas and an ecological reserve was determined. Abundance of capybaras varied between areas and over the sampling period and these differences were related to human activities. A positive correlation was found between capybara and tick abundance, however, the tick species had an uneven distribution within the municipality and environmental factors rather than host availability were blamed for such. On the whole these observations show that capybara populations in urban areas are associated to high environmental infestation of ticks and the increased risk of bites and of pathogen transmission to humans. At the same time the uneven distribution of tick species might implicate in an unequal risk of tick-borne diseases within the same urban area.

  7. Null model analysis of species associations using abundance data.

    PubMed

    Ulrich, Werner; Gotelli, Nicholas J

    2010-11-01

    The influence of negative species interactions has dominated much of the literature on community assembly rules. Patterns of negative covariation among species are typically documented through null model analyses of binary presence/absence matrices in which rows designate species, columns designate sites, and the matrix entries indicate the presence (1) or absence (0) of a particular species in a particular site. However, the outcome of species interactions ultimately depends on population-level processes. Therefore, patterns of species segregation and aggregation might be more clearly expressed in abundance matrices, in which the matrix entries indicate the abundance or density of a species in a particular site. We conducted a series of benchmark tests to evaluate the performance of 14 candidate null model algorithms and six covariation metrics that can be used with abundance matrices. We first created a series of random test matrices by sampling a metacommunity from a lognormal species abundance distribution. We also created a series of structured matrices by altering the random matrices to incorporate patterns of pairwise species segregation and aggregation. We next screened each algorithm-index combination with the random and structured matrices to determine which tests had low Type I error rates and good power for detecting segregated and aggregated species distributions. In our benchmark tests, the best-performing null model does not constrain species richness, but assigns individuals to matrix cells proportional to the observed row and column marginal distributions until, for each row and column, total abundances are reached. Using this null model algorithm with a set of four covariance metrics, we tested for patterns of species segregation and aggregation in a collection of 149 empirical abundance matrices and 36 interaction matrices collated from published papers and posted data sets. More than 80% of the matrices were significantly segregated, which

  8. Relative species abundance of replicator dynamics with sparse interactions

    NASA Astrophysics Data System (ADS)

    Obuchi, Tomoyuki; Kabashima, Yoshiyuki; Tokita, Kei

    2016-11-01

    A theory of relative species abundance on sparsely-connected networks is presented by investigating the replicator dynamics with symmetric interactions. Sparseness of a network involves difficulty in analyzing the fixed points of the equation, and we avoid this problem by treating large self interaction u, which allows us to construct a perturbative expansion. Based on this perturbation, we find that the nature of the interactions is directly connected to the abundance distribution, and some characteristic behaviors, such as multiple peaks in the abundance distribution and all species coexistence at moderate values of u, are discovered in a wide class of the distribution of the interactions. The all species coexistence collapses at a critical value of u, u c , and this collapsing is regarded as a phase transition. To get more quantitative information, we also construct a non-perturbative theory on random graphs based on techniques of statistical mechanics. The result shows those characteristic behaviors are sustained well even for not large u. For even smaller values of u, extinct species start to appear and the abundance distribution becomes rounded and closer to a standard functional form. Another interesting finding is the non-monotonic behavior of diversity, which quantifies the number of coexisting species, when changing the ratio of mutualistic relations Δ . These results are examined by numerical simulations, which show that our theory is exact for the case without extinct species, but becomes less and less precise as the proportion of extinct species grows.

  9. Genetic markers for the identification of two tick species, Amblyomma dissimile and Amblyomma rotundatum.

    PubMed

    Lampo, M; Rangel, Y; Mata, A

    1997-06-01

    Genetic markers are described for 2 species of reptile and amphibian ticks, Amblyomma dissimile and Amblyomma rotundatum, by allozyme electrophoresis. Fixed allelic differences in 4 out of the 8 examined loci allowed the unequivocal separation of both of these species. A strong correlation was found between these genetic markers and the relative size of the spurs in coxae IV but not with the punctuation pattern of the scutum. Moreover, no overlap was found in the distribution of relative spur sizes between samples of both species. The percent polymorphic loci and the mean percent heterozygosity per locus for A. rotundatum was considerably lower than that for A. dissimile. Differences in the amount of genetic variability may be related to their modes of reproduction.

  10. Estimating abundance in the presence of species uncertainty

    USGS Publications Warehouse

    Chambert, Thierry A; Hossack, Blake R.; Fishback, LeeAnn; Davenport, Jon M.

    2016-01-01

    1.N-mixture models have become a popular method for estimating abundance of free-ranging animals that are not marked or identified individually. These models have been used on count data for single species that can be identified with certainty. However, co-occurring species often look similar during one or more life stages, making it difficult to assign species for all recorded captures. This uncertainty creates problems for estimating species-specific abundance and it can often limit life stages to which we can make inference. 2.We present a new extension of N-mixture models that accounts for species uncertainty. In addition to estimating site-specific abundances and detection probabilities, this model allows estimating probability of correct assignment of species identity. We implement this hierarchical model in a Bayesian framework and provide all code for running the model in BUGS-language programs. 3.We present an application of the model on count data from two sympatric freshwater fishes, the brook stickleback (Culaea inconstans) and the ninespine stickleback (Pungitius pungitius), ad illustrate implementation of covariate effects (habitat characteristics). In addition, we used a simulation study to validate the model and illustrate potential sample size issues. We also compared, for both real and simulated data, estimates provided by our model to those obtained by a simple N-mixture model when captures of unknown species identification were discarded. In the latter case, abundance estimates appeared highly biased and very imprecise, while our new model provided unbiased estimates with higher precision. 4.This extension of the N-mixture model should be useful for a wide variety of studies and taxa, as species uncertainty is a common issue. It should notably help improve investigation of abundance and vital rate characteristics of organisms’ early life stages, which are sometimes more difficult to identify than adults.

  11. Environmental correlates of species rank - abundance distributions in global drylands.

    PubMed

    Ulrich, Werner; Soliveres, Santiago; Thomas, Andrew D; Dougill, Andrew J; Maestre, Fernando T

    2016-06-01

    Theoretical models predict lognormal species abundance distributions (SADs) in stable and productive environments, with log-series SADs in less stable, dispersal driven communities. We studied patterns of relative species abundances of perennial vascular plants in global dryland communities to: i) assess the influence of climatic and soil characteristics on the observed SADs, ii) infer how environmental variability influences relative abundances, and iii) evaluate how colonisation dynamics and environmental filters shape abundance distributions. We fitted lognormal and log-series SADs to 91 sites containing at least 15 species of perennial vascular plants. The dependence of species relative abundances on soil and climate variables was assessed using general linear models. Irrespective of habitat type and latitude, the majority of the SADs (70.3%) were best described by a lognormal distribution. Lognormal SADs were associated with low annual precipitation, higher aridity, high soil carbon content, and higher variability of climate variables and soil nitrate. Our results do not corroborate models predicting the prevalence of log-series SADs in dryland communities. As lognormal SADs were particularly associated with sites with drier conditions and a higher environmental variability, we reject models linking lognormality to environmental stability and high productivity conditions. Instead our results point to the prevalence of lognormal SADs in heterogeneous environments, allowing for more evenly distributed plant communities, or in stressful ecosystems, which are generally shaped by strong habitat filters and limited colonisation. This suggests that drylands may be resilient to environmental changes because the many species with intermediate relative abundances could take over ecosystem functioning if the environment becomes suboptimal for dominant species.

  12. Questing ixodid ticks on the vegetation of sable antelope and multi-herbivore enclosures in Thabazimbi.

    PubMed

    Uys, André C; Horak, Ivan G; Harrison, Alan

    2015-07-14

    This survey of ixodid ticks was the first to compare the species composition and population dynamics of free-living ticks in intensive, sable antelope breeding enclosures, now commonplace in commercial wildlife ranching in South Africa, with those of multi-herbivore enclosures. The species composition, abundance and seasonal abundance of questing ixodid ticks on the vegetation in intensive breeding enclosures for sable antelope (Hippotragus niger), on which strategic tick control is practised, were compared with those of ticks in a multi-species herbivore enclosure surrounding the breeding enclosures in which no tick control is practised. A total of eight ixodid tick species were collected by drag-sampling the woodland and grassland habitats in each enclosure type monthly from July 2011 to July 2013. Rhipicephalus decoloratus, a potential vector of fatal tick-borne disease in sable antelopes, was the most abundant, accounting for 65.4% of the total number of ticks collected in the sable enclosures, whilst representing only 25.4% of number of ticks collected in the multi-species herbivore enclosure. Rhipicephalus decoloratus and R. evertsi evertsi were more abundant than R. appendiculatus (both p < 0.05) and Amblyomma hebraeum (p < 0.001 and p < 0.01, respectively). Rhipicephalus decoloratus larvae were collected throughout the year, with peak collections in November 2012 and October to December 2013 in the sable enclosures; and in April/May 2012 and February/April 2013 in the multi-species herbivore enclosure. More R. decoloratus were recovered in the second year than in the first year in the grassland habitat of the sable enclosures (V = 7.0, p < 0.05) possibly as a result of acaricide resistance. The apparent temporal over-abundance of R. decoloratus in sable antelope breeding enclosures, in the face of strategic tick control, is of concern and requires further investigation.

  13. [Abundance of larvae and nymphs of the taiga tick Ixodes persuicatus (Acari: Ixodidae) on small mammals in the cut-over lands of the middle taiga subzone of Karelia].

    PubMed

    Bugmyrin, S V; Bespiatova, L A; Anikanova, V S; Ieshko, E P

    2009-01-01

    Data of long-term investigations (1998-2004) on the abundance of the taiga tick larvae and nymphs in the cut-over lands of different age in the middle taiga subzone of Karelia (62 degrees 04'S; 33 degrees 55'W) are presented. The investigation was carried out on three model cut-over lands of different age: 1) "young" cut-over land; age of cut-over in the beginning of investigation is 7 years; Betula-Deschampsia cespitosa-Agrostis tenuis; 2) "middle" cut-over land; age of cut-over is 12 years; Salix-Deschampsia cespitosa-Agrostis tenuis; 3) "old" cut-over land; age of cut-over 25 years; Alnus incana-Rubus idaeus-grass. The number of ticks was estimated by using common parasitological indices: prevalence, abundance, and index of feeding intensity (the tick abundance multiply by the number of small mammals per hundred traps-nights). In the beginning of investigation the "young" cut-over land was a typical meadow association. The lowest tick abundance was recorded here. That was a result of unfavorable abiotic conditions and low number of small mammals in the beginning of summer. "Middle" cut-over land is characterized by the highest number of the tick larvae, which is the evidence for high number of the hosts of tick imago. "Old" cut-over land has the optimum conditions for development of taiga ticks. High abundance of the ticks (larvae and nymphs) was recorded during the whole period of investigations. The number of preimaginal ticks is shown to be much higher in cut-over lands as compared with that in mixed and coniferous forests, due to the higher number of small mammals.

  14. Relating species abundance distributions to species-area curves in two Mediterranean-type shrublands

    USGS Publications Warehouse

    Keeley, Jon E.

    2003-01-01

    Based on both theoretical and empirical studies there is evidence that different species abundance distributions underlie different species-area relationships. Here I show that Australian and Californian shrubland communities (at the scale from 1 to 1000 m2) exhibit different species-area relationships and different species abundance patterns. The species-area relationship in Australian heathlands best fits an exponential model and species abundance (based on both density and cover) follows a narrow log normal distribution. In contrast, the species-area relationship in Californian shrublands is best fit with the power model and, although species abundance appears to fit a log normal distribution, the distribution is much broader than in Australian heathlands. I hypothesize that the primary driver of these differences is the abundance of small-stature annual species in California and the lack of annuals in Australian heathlands. Species-area is best fit by an exponential model in Australian heathlands because the bulk of the species are common and thus the species-area curves initially rise rapidly between 1 and 100 m2. Annuals in Californian shrublands generate very broad species abundance distributions with many uncommon or rare species. The power function is a better model in these communities because richness increases slowly from 1 to 100 m2 but more rapidly between 100 and 1000 m2due to the abundance of rare or uncommon species that are more likely to be encountered at coarser spatial scales. The implications of this study are that both the exponential and power function models are legitimate representations of species-area relationships in different plant communities. Also, structural differences in community organization, arising from different species abundance distributions, may lead to different species-area curves, and this may be tied to patterns of life form distribution.

  15. The Phenology of Ticks and the Effects of Long-Term Prescribed Burning on Tick Population Dynamics in Southwestern Georgia and Northwestern Florida

    PubMed Central

    Gleim, Elizabeth R.; Conner, L. Mike; Berghaus, Roy D.; Levin, Michael L.; Zemtsova, Galina E.; Yabsley, Michael J.

    2014-01-01

    Some tick populations have increased dramatically in the past several decades leading to an increase in the incidence and emergence of tick-borne diseases. Management strategies that can effectively reduce tick populations while better understanding regional tick phenology is needed. One promising management strategy is prescribed burning. However, the efficacy of prescribed burning as a mechanism for tick control is unclear because past studies have provided conflicting data, likely due to a failure of some studies to simulate operational management scenarios and/or account for other predictors of tick abundance. Therefore, our study was conducted to increase knowledge of tick population dynamics relative to long-term prescribed fire management. Furthermore, we targeted a region, southwestern Georgia and northwestern Florida (USA), in which little is known regarding tick dynamics so that basic phenology could be determined. Twenty-one plots with varying burn regimes (burned surrounded by burned [BB], burned surrounded by unburned [BUB], unburned surrounded by burned [UBB], and unburned surrounded by unburned [UBUB]) were sampled monthly for two years while simultaneously collecting data on variables that can affect tick abundance (e.g., host abundance, vegetation structure, and micro- and macro-climatic conditions). In total, 47,185 ticks were collected, of which, 99% were Amblyomma americanum, 0.7% were Ixodes scapularis, and fewer numbers of Amblyomma maculatum, Ixodes brunneus, and Dermacentor variabilis. Monthly seasonality trends were similar between 2010 and 2011. Long-term prescribed burning consistently and significantly reduced tick counts (overall and specifically for A. americanum and I. scapularis) regardless of the burn regimes and variables evaluated. Tick species composition varied according to burn regime with A. americanum dominating at UBUB, A. maculatum at BB, I. scapularis at UBB, and a more even composition at BUB. These data indicate that

  16. The effects of acoustic misclassification on cetacean species abundance estimation.

    PubMed

    Caillat, Marjolaine; Thomas, Len; Gillespie, Douglas

    2013-09-01

    To estimate the density or abundance of a cetacean species using acoustic detection data, it is necessary to correctly identify the species that are detected. Developing an automated species classifier with 100% correct classification rate for any species is likely to stay out of reach. It is therefore necessary to consider the effect of misidentified detections on the number of observed data and consequently on abundance or density estimation, and develop methods to cope with these misidentifications. If misclassification rates are known, it is possible to estimate the true numbers of detected calls without bias. However, misclassification and uncertainties in the level of misclassification increase the variance of the estimates. If the true numbers of calls from different species are similar, then a small amount of misclassification between species and a small amount of uncertainty around the classification probabilities does not have an overly detrimental effect on the overall variance. However, if there is a difference in the encounter rate between species calls and/or a large amount of uncertainty in misclassification rates, then the variance of the estimates becomes very large and this dramatically increases the variance of the final abundance estimate.

  17. Factors affecting Culicoides species composition and abundance in avian nests.

    PubMed

    Martínez-de la Puente, J; Merino, S; Tomás, G; Moreno, J; Morales, J; Lobato, E; Talavera, S; Sarto I Monteys, V

    2009-08-01

    Mechanisms affecting patterns of vector distribution among host individuals may influence the population and evolutionary dynamics of vectors, hosts and the parasites transmitted. We studied the role of different factors affecting the species composition and abundance of Culicoides found in nests of the blue tit (Cyanistes caeruleus). We identified 1531 females and 2 males of 7 different Culicoides species in nests, with C. simulator being the most abundant species, followed by C. kibunensis, C. festivipennis, C. segnis, C. truncorum, C. pictipennis and C. circumscriptus. We conducted a medicationxfumigation experiment randomly assigning bird's nests to different treatments, thereby generating groups of medicated and control pairs breeding in fumigated and control nests. Medicated pairs were injected with the anti-malarial drug Primaquine diluted in saline solution while control pairs were injected with saline solution. The fumigation treatment was carried out using insecticide solution or water for fumigated and control nests respectively. Brood size was the main factor associated with the abundance of biting midges probably because more nestlings may produce higher quantities of vector attractants. In addition, birds medicated against haemoparasites breeding in non-fumigated nests supported a higher abundance of C. festivipennis than the rest of the groups. Also, we found that the fumigation treatment reduced the abundance of engorged Culicoides in both medicated and control nests, thus indicating a reduction of feeding success produced by the insecticide. These results represent the first evidence for the role of different factors in affecting the Culicoides infracommunity in wild avian nests.

  18. Molecular evidence for a spotted fever group Rickettsia species in the tick Amblyomma longirostre in Brazil.

    PubMed

    Labruna, Marcelo B; McBride, Jere W; Bouyer, Donal H; Camargo, Luis Marcelo A; Camargo, Erney P; Walker, David H

    2004-05-01

    Two Amblyomma longirostre adult male ticks were collected from a Brazilian porcupine Coendou prehensilis L. in the state of Rondonia, Western Amazon, Brazil. The two ticks were pooled for DNA extraction and tested for the presence of rickettsial DNA by amplifying portions of the gltA, 17-kDa, ompA, and ompB rickettsial genes by polymerase chain reaction (PCR). Portions of the four genes were amplified from the sample and subsequently sequenced. These results indicated the presence of a Rickettsia strain infecting A. longirostre, which was designated as strain Aranha. Compared with homologous ompA rickettsial sequences, "Rickettsia amblyommii" ompA seemed to be the closest relative to Aranha (similarity values: 99.0-99.3%). Phylogenetic analyses of more conserved genes including 17-kDa and gtlA partial sequences indicated that this Rickettsia sp. is a spotted fever group rickettsia. The partial ompB sequence of strain Aranha was distinct from all homologous sequences available in GenBank. Although our ompA analysis suggested a very close molecular phylogenetic relationship of Aranha with "R. amblyommii," we cannot at this time determine if Aranha is a new strain of "R. amblyommii" or a new Rickettsia species in South America.

  19. Abundance of common species, not species richness, drives delivery of a real-world ecosystem service.

    PubMed

    Winfree, Rachael; Fox, Jeremy W; Williams, Neal M; Reilly, James R; Cariveau, Daniel P

    2015-07-01

    Biodiversity-ecosystem functioning experiments have established that species richness and composition are both important determinants of ecosystem function in an experimental context. Determining whether this result holds for real-world ecosystem services has remained elusive, however, largely due to the lack of analytical methods appropriate for large-scale, associational data. Here, we use a novel analytical approach, the Price equation, to partition the contribution to ecosystem services made by species richness, composition and abundance in four large-scale data sets on crop pollination by native bees. We found that abundance fluctuations of dominant species drove ecosystem service delivery, whereas richness changes were relatively unimportant because they primarily involved rare species that contributed little to function. Thus, the mechanism behind our results was the skewed species-abundance distribution. Our finding that a few common species, not species richness, drive ecosystem service delivery could have broad generality given the ubiquity of skewed species-abundance distributions in nature.

  20. Measuring β-diversity with species abundance data.

    PubMed

    Barwell, Louise J; Isaac, Nick J B; Kunin, William E

    2015-07-01

    In 2003, 24 presence-absence β-diversity metrics were reviewed and a number of trade-offs and redundancies identified. We present a parallel investigation into the performance of abundance-based metrics of β-diversity. β-diversity is a multi-faceted concept, central to spatial ecology. There are multiple metrics available to quantify it: the choice of metric is an important decision. We test 16 conceptual properties and two sampling properties of a β-diversity metric: metrics should be 1) independent of α-diversity and 2) cumulative along a gradient of species turnover. Similarity should be 3) probabilistic when assemblages are independently and identically distributed. Metrics should have 4) a minimum of zero and increase monotonically with the degree of 5) species turnover, 6) decoupling of species ranks and 7) evenness differences. However, complete species turnover should always generate greater values of β than extreme 8) rank shifts or 9) evenness differences. Metrics should 10) have a fixed upper limit, 11) symmetry (βA,B  = βB,A ), 12) double-zero asymmetry for double absences and double presences and 13) not decrease in a series of nested assemblages. Additionally, metrics should be independent of 14) species replication 15) the units of abundance and 16) differences in total abundance between sampling units. When samples are used to infer β-diversity, metrics should be 1) independent of sample sizes and 2) independent of unequal sample sizes. We test 29 metrics for these properties and five 'personality' properties. Thirteen metrics were outperformed or equalled across all conceptual and sampling properties. Differences in sensitivity to species' abundance lead to a performance trade-off between sample size bias and the ability to detect turnover among rare species. In general, abundance-based metrics are substantially less biased in the face of undersampling, although the presence-absence metric, βsim , performed well overall. Only

  1. Are ticks venomous animals?

    PubMed Central

    2014-01-01

    Introduction As an ecological adaptation venoms have evolved independently in several species of Metazoa. As haematophagous arthropods ticks are mainly considered as ectoparasites due to directly feeding on the skin of animal hosts. Ticks are of major importance since they serve as vectors for several diseases affecting humans and livestock animals. Ticks are rarely considered as venomous animals despite that tick saliva contains several protein families present in venomous taxa and that many Ixodida genera can induce paralysis and other types of toxicoses. Tick saliva was previously proposed as a special kind of venom since tick venom is used for blood feeding that counteracts host defense mechanisms. As a result, the present study provides evidence to reconsider the venomous properties of tick saliva. Results Based on our extensive literature mining and in silico research, we demonstrate that ticks share several similarities with other venomous taxa. Many tick salivary protein families and their previously described functions are homologous to proteins found in scorpion, spider, snake, platypus and bee venoms. This infers that there is a structural and functional convergence between several molecular components in tick saliva and the venoms from other recognized venomous taxa. We also highlight the fact that the immune response against tick saliva and venoms (from recognized venomous taxa) are both dominated by an allergic immunity background. Furthermore, by comparing the major molecular components of human saliva, as an example of a non-venomous animal, with that of ticks we find evidence that ticks resemble more venomous than non-venomous animals. Finally, we introduce our considerations regarding the evolution of venoms in Arachnida. Conclusions Taking into account the composition of tick saliva, the venomous functions that ticks have while interacting with their hosts, and the distinguishable differences between human (non-venomous) and tick salivary

  2. Comparing feeding and reproductive parameters of Amblyomma parvum tick populations (Acari: Ixodidae) from Brazil and Argentina on various host species.

    PubMed

    Gerardi, Monize; Martins, Maria Marlene; Nava, Santiago; Szabó, Matias Pablo Juan

    2013-10-18

    Amblyomma parvum is a Neotropical tick that is widely spread and a potential vector of pathogens, including Rickettsiae. Genetic differences are remarkable between A. parvum populations from Brazil and Argentina. In this work, feeding and reproduction parameters of A. parvum ticks from these two populations were compared on some key host species to evaluate possible differences in host suitability between them. On the whole parameters of these tick populations were similar when fed on the same host and varied similarly on different host species. Still, bovines were more suitable host for Argentinian larvae than for Brazilian cohorts. It was observed that guinea pigs were the best host A. parvum immatures from both origins, as depicted from higher recovery rate of larvae and heavier engorged nymph weights. Canids and bovids were host species most suitable to adults of both tick populations as shown by the highest number of larvae produced by adult females that engorged on these hosts. Taken together, results showed that in spite of the genetic divergence, A. parvum from Argentina and Brazil have similar biological performance on various host species.

  3. Ticks infesting bats (Mammalia: Chiroptera) in the Brazilian Pantanal.

    PubMed

    Muñoz-Leal, Sebastián; Eriksson, Alan; Santos, Carolina Ferreira; Fischer, Erich; de Almeida, Juliana Cardoso; Luz, Hermes R; Labruna, Marcelo B

    2016-05-01

    Ticks associated with bats have been poorly documented in the Neotropical Zoogeographical Region. In this study, a total of 1028 bats were sampled for tick infestations in the southern portion of the Brazilian Pantanal. A total of 368 ticks, morphologically identified as Ornithodoros hasei (n = 364) and O. mimon (n = 4), were collected from the following bat species: Artibeus planirostris, Platyrrhinus lineatus, Phyllostomus hastatus, Mimon crenulatum and Noctilio albiventris. Morphological identification of O. hasei was confirmed by molecular analysis. Regarding the most abundant bat species, only 40 (6.2%) out of 650 A. planirostris were infested by O. hasei, with a mean intensity of 7.2 ticks per infested bat, or a mean abundance of 0.44 ticks per sampled bat. Noteworthy, one single P. hastatus was infested by 55 O. hasei larvae, in contrast to the 2.5-7.2 range of mean intensity values for the whole study. As a complement to the present study, a total of 8 museum bat specimens (6 Noctilio albiventris and 2 N. leporinus), collected in the northern region of Pantanal, were examined for tick infestations. These bats contained 176 ticks, which were all morphologically identified as O. hasei larvae. Mean intensity of infestation was 22, with a range of 1-46 ticks per infested bat. Our results suggest that A. planirostris might play an important role in the natural life cycle of O. hasei in the Pantanal.

  4. Effects of Climate Change on Ticks and Tick-Borne Diseases in Europe

    PubMed Central

    Gray, J. S.; Dautel, H.; Estrada-Peña, A.; Kahl, O.; Lindgren, E.

    2009-01-01

    Zoonotic tick-borne diseases are an increasing health burden in Europe and there is speculation that this is partly due to climate change affecting vector biology and disease transmission. Data on the vector tick Ixodes ricinus suggest that an extension of its northern and altitude range has been accompanied by an increased prevalence of tick-borne encephalitis. Climate change may also be partly responsible for the change in distribution of Dermacentor reticulatus. Increased winter activity of I. ricinus is probably due to warmer winters and a retrospective study suggests that hotter summers will change the dynamics and pattern of seasonal activity, resulting in the bulk of the tick population becoming active in the latter part of the year. Climate suitability models predict that eight important tick species are likely to establish more northern permanent populations in a climate-warming scenario. However, the complex ecology and epidemiology of such tick-borne diseases as Lyme borreliosis and tick-borne encephalitis make it difficult to implicate climate change as the main cause of their increasing prevalence. Climate change models are required that take account of the dynamic biological processes involved in vector abundance and pathogen transmission in order to predict future tick-borne disease scenarios. PMID:19277106

  5. Rhipicephalus rossicus and not R. sanguineus is the dominant tick species of dogs in the wetlands of the Danube Delta, Romania.

    PubMed

    Sándor, Attila D; Dumitrache, Mirabela O; D'Amico, Gianluca; Kiss, Botond J; Mihalca, Andrei D

    2014-08-29

    Changes in the distribution of tick species are among the major causes for the increase in prevalence of zoonotic diseases worldwide, with tick-borne diseases' prevalence showing an emerging pattern. One of these ticks, Rhipicephalus rossicus, which is reported occasionally from humans, seems to be particularly interesting because of its demonstrated vectorial role for zoonotic pathogens like Francisella tularensis, Coxiella burnetii, or CCHF and West Nile viruses. Here we report a case of dominant occurrence of R. rossicus on household dogs in the wetlands of Eastern Europe (Romania). Ticks were collected from dogs in 5 distinct locations, with 1068 ticks of 6 species found. R. rossicus had a dominant occurrence in dogs in all but one location, accounting for 87.1% of all ticks (32.3-95.3% in different locations). Until this study, Rhipicephalus sanguineus was considered as the only important tick species on dogs in south-temperate regions of Europe, as well in Romania. The dominant presence of R. rossicus in dogs, its vectorial competence and broad host spectrum (including humans), make this tick species an important candidate for further analysis and highlight the paucity of our knowledge on disease vectors in this region of Europe.

  6. Assessing introduction risk using species' rank-abundance distributions.

    PubMed

    Chan, Farrah T; Bradie, Johanna; Briski, Elizabeta; Bailey, Sarah A; Simard, Nathalie; MacIsaac, Hugh J

    2015-01-22

    Mixed-species assemblages are often unintentionally introduced into new ecosystems. Analysing how assemblage structure varies during transport may provide insights into how introduction risk changes before propagules are released. Characterization of introduction risk is typically based on assessments of colonization pressure (CP, the number of species transported) and total propagule pressure (total PP, the total abundance of propagules released) associated with an invasion vector. Generally, invasion potential following introduction increases with greater CP or total PP. Here, we extend these assessments using rank-abundance distributions to examine how CP : total PP relationships change temporally in ballast water of ocean-going ships. Rank-abundance distributions and CP : total PP patterns varied widely between trans-Atlantic and trans-Pacific voyages, with the latter appearing to pose a much lower risk than the former. Responses also differed by taxonomic group, with invertebrates experiencing losses mainly in total PP, while diatoms and dinoflagellates sustained losses mainly in CP. In certain cases, open-ocean ballast water exchange appeared to increase introduction risk by uptake of new species or supplementation of existing ones. Our study demonstrates that rank-abundance distributions provide new insights into the utility of CP and PP in characterizing introduction risk.

  7. Species richness, equitability, and abundance of ants in disturbed landscapes

    USGS Publications Warehouse

    Graham, J.H.; Krzysik, A.J.; Kovacic, D.A.; Duda, J.J.; Freeman, D.C.; Emlen, J.M.; Zak, J.C.; Long, W.R.; Wallace, M.P.; Chamberlin-Graham, C.; Nutter, J.P.; Balbach, H.E.

    2009-01-01

    Ants are used as indicators of environmental change in disturbed landscapes, often without adequate understanding of their response to disturbance. Ant communities in the southeastern United States displayed a hump-backed species richness curve against an index of landscape disturbance. Forty sites at Fort Benning, in west-central Georgia, covered a spectrum of habitat disturbance (military training and fire) in upland forest. Sites disturbed by military training had fewer trees, less canopy cover, more bare ground, and warmer, more compact soils with shallower A-horizons. We sampled ground-dwelling ants with pitfall traps, and measured 15 habitat variables related to vegetation and soil. Ant species richness was greatest with a relative disturbance of 43%, but equitability was greatest with no disturbance. Ant abundance was greatest with a relative disturbance of 85%. High species richness at intermediate disturbance was associated with greater within-site spatial heterogeneity. Species richness was also associated with intermediate values of the normalized difference vegetation index (NDVI), a correlate of net primary productivity (NPP). Available NPP (the product of NDVI and the fraction of days that soil temperature exceeded 25 ??C), however, was positively correlated with species richness, though not with ant abundance. Species richness was unrelated to soil texture, total ground cover, and fire frequency. Ant species richness and equitability are potential state indicators of the soil arthropod community. Moreover, equitability can be used to monitor ecosystem change. ?? 2008 Elsevier Ltd.

  8. Inferring invasive species abundance using removal data from management actions.

    PubMed

    Davis, Amy J; Hooten, Mevin B; Miller, Ryan S; Farnsworth, Matthew L; Lewis, Jesse; Moxcey, Michael; Pepin, Kim M

    2016-10-01

    Evaluation of the progress of management programs for invasive species is crucial for demonstrating impacts to stakeholders and strategic planning of resource allocation. Estimates of abundance before and after management activities can serve as a useful metric of population management programs. However, many methods of estimating population size are too labor intensive and costly to implement, posing restrictive levels of burden on operational programs. Removal models are a reliable method for estimating abundance before and after management using data from the removal activities exclusively, thus requiring no work in addition to management. We developed a Bayesian hierarchical model to estimate abundance from removal data accounting for varying levels of effort, and used simulations to assess the conditions under which reliable population estimates are obtained. We applied this model to estimate site-specific abundance of an invasive species, feral swine (Sus scrofa), using removal data from aerial gunning in 59 site/time-frame combinations (480-19,600 acres) throughout Oklahoma and Texas, USA. Simulations showed that abundance estimates were generally accurate when effective removal rates (removal rate accounting for total effort) were above 0.40. However, when abundances were small (<50) the effective removal rate needed to accurately estimates abundances was considerably higher (0.70). Based on our post-validation method, 78% of our site/time frame estimates were accurate. To use this modeling framework it is important to have multiple removals (more than three) within a time frame during which demographic changes are minimized (i.e., a closed population; ≤3 months for feral swine). Our results show that the probability of accurately estimating abundance from this model improves with increased sampling effort (8+ flight hours across the 3-month window is best) and increased removal rate. Based on the inverse relationship between inaccurate abundances and

  9. Inferring invasive species abundance using removal data from management actions

    USGS Publications Warehouse

    Davis, Amy J.; Hooten, Mevin B.; Miller, Ryan S.; Farnsworth, Matthew L.; Lewis, Jesse S.; Moxcey, Michael; Pepin, Kim M.

    2016-01-01

    Evaluation of the progress of management programs for invasive species is crucial for demonstrating impacts to stakeholders and strategic planning of resource allocation. Estimates of abundance before and after management activities can serve as a useful metric of population management programs. However, many methods of estimating population size are too labor intensive and costly to implement, posing restrictive levels of burden on operational programs. Removal models are a reliable method for estimating abundance before and after management using data from the removal activities exclusively, thus requiring no work in addition to management. We developed a Bayesian hierarchical model to estimate abundance from removal data accounting for varying levels of effort, and used simulations to assess the conditions under which reliable population estimates are obtained. We applied this model to estimate site-specific abundance of an invasive species, feral swine (Sus scrofa), using removal data from aerial gunning in 59 site/time-frame combinations (480–19,600 acres) throughout Oklahoma and Texas, USA. Simulations showed that abundance estimates were generally accurate when effective removal rates (removal rate accounting for total effort) were above 0.40. However, when abundances were small (<50) the effective removal rate needed to accurately estimates abundances was considerably higher (0.70). Based on our post-validation method, 78% of our site/time frame estimates were accurate. To use this modeling framework it is important to have multiple removals (more than three) within a time frame during which demographic changes are minimized (i.e., a closed population; ≤3 months for feral swine). Our results show that the probability of accurately estimating abundance from this model improves with increased sampling effort (8+ flight hours across the 3-month window is best) and increased removal rate. Based on the inverse relationship between inaccurate abundances and

  10. Stop Ticks

    MedlinePlus

    ... and bringing ticks with them. Prevent Ticks on Animals Use tick control products to prevent family pets ... medications should be used regularly to protect your animals and your family from ticks. Consult your veterinarian ...

  11. Tick bite

    MedlinePlus

    ... Images Lyme disease, erythema migrans Lyme disease organism, Borrelia burgdorferi Deer ticks Ticks Tick, deer engorged on the skin Lyme disease - Borrelia burgdorferi organism Tick, deer - adult female Deer and dog ...

  12. Foraminifera Species Richness, Abundance, and Diversity Research in Bolinas, California

    NASA Astrophysics Data System (ADS)

    Brunwin, N.; Ingram, Z.; Mendez, M.; Sandoval, K.

    2015-12-01

    Foraminifera are abundant, diverse, respond rapidly to environmental change, and are present in all marine and estuarine environments, making them important indicator species. A survey of occurrence and distribution of foraminifera in the Bolinas Lagoon, Marin County, California was carried out by Hedman in 1975, but no study since has focused on foraminiferal composition within this important ecosystem. In July 2015, the Careers in Science (CiS) Intern Program collected samples at 12 sites previously examined in the 1975 study. Thirty-six samples were collected from the upper few centimeters of sediment from a variety of intertidal and subtidal environments within the lagoon. Foraminifera from each sample were isolated, identified and species richness, abundance and diversity quantified. Furthermore, comparisons of faunal composition represented in our recent collection and that of Hedman's 1975 report are made.

  13. Abiotic and biotic determinants of tick burdens in the eastern rock sengi (Elephantulus myurus).

    PubMed

    Lutermann, H; Medger, K; Horak, I G

    2012-09-01

    Ticks are important vectors of pathogens of medical and veterinary importance worldwide. In spite of their economic importance, our current knowledge about the factors affecting tick prevalence and abundance in tropical and subtropical regions is rather limited. Both abiotic (e.g. temperature) as well as biotic variables (e.g. host sex) have been identified as key determinants of distributions. Eastern rock sengis or elephant shrews (Elephantulus myurus, Macroscelidea: Cacroscelididae, Thomas & Schwann) are widely distributed throughout Africa and can harbour a large number of tick species and substantial tick burdens. In the present study, we evaluated the contribution of climate and host factors on tick burdens of sengis. Throughout the year sengis carried high abundances of immature stages of a single tick species, Rhipicephalus sp. near warburtoni. There was no evidence that host parameters affected tick burdens. However, larval abundance decreased with increasing ambient temperatures and both larvae and nymphs were negatively affected by rainfall 2 months before the sampling month. In addition, nymphal burdens decreased with increasing minimum temperatures. Our results suggest that climate factors are the largest constraint for the immature stages of R. sp. near warburtoni and that eastern rock sengis could play a crucial role in the dynamics of tick-borne diseases as a result of the large tick burdens they can sustain.

  14. Interstellar isomeric species: Energy, stability and abundance relationship

    NASA Astrophysics Data System (ADS)

    Etim, Emmanuel E.; Arunan, Elangannan

    2016-12-01

    Accurate enthalpies of formation are reported for known and potential interstellar isomeric species using high-level ab initio quantum-chemical calculations. A total of 130 molecules comprising of 31 isomeric groups and 24 cyanide/isocyanide pairs with molecules ranging from 3 to 12 atoms have been considered. The results show an interesting relationship between energy, stability and abundance (ESA) existing among these molecules. Among the isomeric species, isomers with lower enthalpies of formation are more easily observed in the interstellar medium compared to their counterparts with higher enthalpies of formation. Available data in the literature confirm the high abundance of the most stable isomer over other isomers in the different groups considered. Potential for interstellar hydrogen bonding accounts for the few exceptions observed. Thus, in general, it suffices to say that the interstellar abundances of related species could be linked to their stabilities if other factors do not dominate. The immediate consequences of this relationship in addressing some of the whys and wherefores among interstellar molecules and in predicting some possible candidates for future astronomical observations are discussed.

  15. A new species of Trichoderma hypoxylon harbours abundant secondary metabolites

    PubMed Central

    Sun, Jingzu; Pei, Yunfei; Li, Erwei; Li, Wei; Hyde, Kevin D.; Yin, Wen-Bing; Liu, Xingzhong

    2016-01-01

    Some species of Trichoderma are fungicolous on fungi and have been extensively studied and commercialized as biocontrol agents. Multigene analyses coupled with morphology, resulted in the discovery of T. hypoxylon sp. nov., which was isolated from surface of the stroma of Hypoxylon anthochroum. The new taxon produces Trichoderma- to Verticillium-like conidiophores and hyaline conidia. Phylogenetic analyses based on combined ITS, TEF1-α and RPB2 sequence data indicated that T. hypoxylon is a well-distinguished species with strong bootstrap support in the polysporum group. Chemical assessment of this species reveals a richness of secondary metabolites with trichothecenes and epipolythiodiketopiperazines as the major compounds. The fungicolous life style of T. hypoxylon and the production of abundant metabolites are indicative of the important ecological roles of this species in nature. PMID:27869187

  16. Molecular detection of zoonotic tick-borne pathogens from ticks collected from ruminants in four South African provinces

    PubMed Central

    MTSHALI, Khethiwe; KHUMALO, Zamantungwa T. H.; NAKAO, Ryo; GRAB, Dennis J.; SUGIMOTO, Chihiro; THEKISOE, Oriel M. M.

    2015-01-01

    Ticks carry and transmit a remarkable array of pathogens including bacteria, protozoa and viruses, which may be of veterinary and/or of medical significance. With little to no information regarding the presence of tick-borne zoonotic pathogens or their known vectors in southern Africa, the aim of our study was to screen for Anaplasma phagocytophilum, Borrelia burgdorferi, Coxiella burnetii, Rickettsia species and Ehrlichia ruminantium in ticks collected and identified from ruminants in the Eastern Cape, Free State, KwaZulu-Natal and Mpumalanga Provinces of South Africa. The most abundant tick species identified in this study were Rhipicephalus evertsi evertsi (40%), Rhipicephalus species (35%), Amblyomma hebraeum (10%) and Rhipicephalus decoloratus (14%). A total of 1634 ticks were collected. DNA was extracted, and samples were subjected to PCR amplification and sequencing. The overall infection rates of ticks with the target pathogens in the four Provinces were as follows: A. phagocytophilum, 7%; C. burnetii, 7%; E. ruminantium, 28%; and Rickettsia spp., 27%. The presence of B. burgdorferi could not be confirmed. The findings of this study show that zoonotic pathogens are present in ticks in the studied South African provinces. This information will aid in the epidemiology of tick-borne zoonotic diseases in the country as well as in raising awareness about such diseases in the veterinary, medical and tourism sectors, as they may be the most affected. PMID:26227797

  17. Molecular detection of zoonotic tick-borne pathogens from ticks collected from ruminants in four South African provinces.

    PubMed

    Mtshali, Khethiwe; Khumalo, Zth; Nakao, Ryo; Grab, Dennis J; Sugimoto, Chihiro; Thekisoe, Omm

    2016-01-01

    Ticks carry and transmit a remarkable array of pathogens including bacteria, protozoa and viruses, which may be of veterinary and/or of medical significance. With little to no information regarding the presence of tick-borne zoonotic pathogens or their known vectors in southern Africa, the aim of our study was to screen for Anaplasma phagocytophilum, Borrelia burgdorferi, Coxiella burnetii, Rickettsia species and Ehrlichia ruminantium in ticks collected and identified from ruminants in the Eastern Cape, Free State, KwaZulu-Natal and Mpumalanga Provinces of South Africa. The most abundant tick species identified in this study were Rhipicephalus evertsi evertsi (40%), Rhipicephalus species (35%), Amblyomma hebraeum (10%) and Rhipicephalus decoloratus (14%). A total of 1634 ticks were collected. DNA was extracted, and samples were subjected to PCR amplification and sequencing. The overall infection rates of ticks with the target pathogens in the four Provinces were as follows: A. phagocytophilum, 7%; C. burnetii, 7%; E. ruminantium, 28%; and Rickettsia spp., 27%. The presence of B. burgdorferi could not be confirmed. The findings of this study show that zoonotic pathogens are present in ticks in the studied South African provinces. This information will aid in the epidemiology of tick-borne zoonotic diseases in the country as well as in raising awareness about such diseases in the veterinary, medical and tourism sectors, as they may be the most affected.

  18. Novel Candidatus Rickettsia Species Detected in Nostril Tick from Human, Gabon, 2014

    PubMed Central

    Lopez-Velez, Rogelio; Palomar, Ana M.; Oteo, José A.; Norman, Francesca F.; Pérez-Molina, José A.

    2015-01-01

    We report the identification of a nymphal nostril tick (Amblyomma sp.) from a national park visitor in Gabon and subsequent molecular detection and characterization of tickborne bacteria. Our findings provide evidence of a potentially new Rickettsia sp. circulating in Africa and indicate that tick bites may pose a risk to persons visiting parks in the region. PMID:25625886

  19. Amblyomma latepunctatum, a valid tick species (Acari: Ixodidae) long misidentified with both amblyomma incisum and Amblyomma scalpturatum.

    PubMed

    Labruna, Marcelo B; Keirans, James E; Camargo, Luis Marcelo A; Ribeiro, Alberto F; Soares, Rodrigo M; Camargo, Erney P

    2005-06-01

    In 2000, we initiated an investigation on the tick fauna of Rondônia State, where we collected many specimens of Amblyomma scalpturatum Neumann, 1906 and Amblyomma incisum Neumann, 1906. In addition, we also collected a third group of ticks that were morphologically closely related to those 2 species, but sufficiently different to be considered a distinct species; members of this group were subsequently identified as Amblyomma latepunctatum Tonelli-Rondelli, 1939, through comparison with the type specimens of this taxon. Herein, we redescribe both sexes of A. scalpturatum and A. incisum, the female of A. latepunctatum, and provide the first description of the male of this latter species. Molecular analysis of the second internal transcribed spacer (ITS2) from rDNA of specimens of the 3 species supports morphological results. Examination of both A. scalpturatum and A. incisum deposited in different tick collections revealed that A. latepunctatum appeared relatively frequently in the vials believed to contain specimens of A. incisum or A. scalpturatum. Before this study, A. latepunctatum was considered a synonym of A. scalpturatum. Herein, we provide morphological and molecular evidence to validate the species A. latepunctatum. The South American tapir (Tapirus terrestris) seems to be the primary host for the adult stage of A. latepunctatum, A. scalpturatum, and A. incisum.

  20. When Can Species Abundance Data Reveal Non-neutrality?

    PubMed Central

    Al Hammal, Omar; Alonso, David; Etienne, Rampal S.; Cornell, Stephen J.

    2015-01-01

    Species abundance distributions (SAD) are probably ecology’s most well-known empirical pattern, and over the last decades many models have been proposed to explain their shape. There is no consensus over which model is correct, because the degree to which different processes can be discerned from SAD patterns has not yet been rigorously quantified. We present a power calculation to quantify our ability to detect deviations from neutrality using species abundance data. We study non-neutral stochastic community models, and show that the presence of non-neutral processes is detectable if sample size is large enough and/or the amplitude of the effect is strong enough. Our framework can be used for any candidate community model that can be simulated on a computer, and determines both the sampling effort required to distinguish between alternative processes, and a range for the strength of non-neutral processes in communities whose patterns are statistically consistent with neutral theory. We find that even data sets of the scale of the 50 Ha forest plot on Barro Colorado Island, Panama, are unlikely to be large enough to detect deviations from neutrality caused by competitive interactions alone, though the presence of multiple non-neutral processes with contrasting effects on abundance distributions may be detectable. PMID:25793889

  1. Abundant Microsatellite Diversity and Oil Content in Wild Arachis Species

    PubMed Central

    Ren, Xiaoping; Chen, Yuning; Xiao, Yingjie; Zhao, Xinyan; Tang, Mei; Huang, Jiaquan; Upadhyaya, Hari D.; Liao, Boshou

    2012-01-01

    The peanut (Arachis hypogaea) is an important oil crop. Breeding for high oil content is becoming increasingly important. Wild Arachis species have been reported to harbor genes for many valuable traits that may enable the improvement of cultivated Arachis hypogaea, such as resistance to pests and disease. However, only limited information is available on variation in oil content. In the present study, a collection of 72 wild Arachis accessions representing 19 species and 3 cultivated peanut accessions were genotyped using 136 genome-wide SSR markers and phenotyped for oil content over three growing seasons. The wild Arachis accessions showed abundant diversity across the 19 species. A. duranensis exhibited the highest diversity, with a Shannon-Weaver diversity index of 0.35. A total of 129 unique alleles were detected in the species studied. A. rigonii exhibited the largest number of unique alleles (75), indicating that this species is highly differentiated. AMOVA and genetic distance analyses confirmed the genetic differentiation between the wild Arachis species. The majority of SSR alleles were detected exclusively in the wild species and not in A. hypogaea, indicating that directional selection or the hitchhiking effect has played an important role in the domestication of the cultivated peanut. The 75 accessions were grouped into three clusters based on population structure and phylogenic analysis, consistent with their taxonomic sections, species and genome types. A. villosa and A. batizocoi were grouped with A. hypogaea, suggesting the close relationship between these two diploid wild species and the cultivated peanut. Considerable phenotypic variation in oil content was observed among different sections and species. Nine alleles were identified as associated with oil content based on association analysis, of these, three alleles were associated with higher oil content but were absent in the cultivated peanut. The results demonstrated that there is great

  2. Biological control of ticks

    USGS Publications Warehouse

    Samish, M.; Ginsberg, H.; Glazer, I.; Bowman, A.S.; Nuttall, P.

    2004-01-01

    Ticks have numerous natural enemies, but only a few species have been evaluated as tick biocontrol agents (BCAs). Some laboratory results suggest that several bacteria are pathogenic to ticks, but their mode of action and their potential value as biocontrol agents remain to be determined. The most promising entomopathogenic fungi appear to be Metarhizium anisopliae and Beauveria bassiana, strains of which are already commercially available for the control of some pests. Development of effective formulations is critical for tick management. Entomopathogenic nematodes that are pathogenic to ticks can potentially control ticks, but improved formulations and selection of novel nematode strains are needed. Parasitoid wasps of the genus Ixodiphagus do not typically control ticks under natural conditions, but inundative releases show potential value. Most predators of ticks are generalists, with a limited potential for tick management (one possible exception is oxpeckers in Africa). Biological control is likely to play a substantial role in future IPM programmes for ticks because of the diversity of taxa that show high potential as tick BCAs. Considerable research is required to select appropriate strains, develop them as BCAs, establish their effectiveness, and devise production strategies to bring them to practical use.

  3. Rickettsia Species Infecting Amblyomma cooperi Ticks from an Area in the State of São Paulo, Brazil, Where Brazilian Spotted Fever Is Endemic

    PubMed Central

    Labruna, Marcelo B.; Whitworth, Ted; Horta, Maurício C.; Bouyer, Donald H.; McBride, Jere W.; Pinter, Adriano; Popov, Vsevolod; Gennari, Solange M.; Walker, David H.

    2004-01-01

    Owing to the potential role of the tick Amblyomma cooperi in the enzootic cycle of Rickettsia rickettsii, the etiologic agent of Brazilian spotted fever (BSF), this study evaluated infection by Rickettsia species in A. cooperi ticks collected from an area in Brazil where BSF is endemic. Among a total of 40 A. cooperi adult ticks collected in an area of BSF endemicity in the state of São Paulo, PCR analysis detected DNA of Rickettsia bellii in 16 ticks (40%), and 3 other ticks (7.5%) were positive for a previously unidentified spotted-fever-group (SFG) rickettsia. Cultivation in Vero cell cultures by the shell vial technique with individual A. cooperi ticks resulted in two isolates of R. bellii and one isolate genotypically characterized as an SFG rickettsia. The two R. bellii isolates were established in Vero cell cultures in the laboratory and were confirmed to be R. bellii by molecular analysis of the gltA and 17-kDa protein-encoding genes and by electron microscopic analysis. The SFG rickettsial isolate could not be stably passaged in cell culture in the laboratory, but molecular analysis of early passages suggested that it was closely related to Rickettsia parkeri, Rickettsia africae, and Rickettsia sibirica. These results do not support the role of A. cooperi in the ecology of R. rickettsii in the area studied, but they add two more species of rickettsiae to the poorly developed list of species occurring in ticks in South America. PMID:14715737

  4. Transport of ixodid ticks and tick-borne pathogens by migratory birds.

    PubMed

    Hasle, Gunnar

    2013-01-01

    Birds, particularly passerines, can be parasitized by Ixodid ticks, which may be infected with tick-borne pathogens, like Borrelia spp., Babesia spp., Anaplasma, Rickettsia/Coxiella, and tick-borne encephalitis virus. The prevalence of ticks on birds varies over years, season, locality and different bird species. The prevalence of ticks on different species depends mainly on the degree of feeding on the ground. In Europe, the Turdus spp., especially the blackbird, Turdus merula, appears to be most important for harboring ticks. Birds can easily cross barriers, like fences, mountains, glaciers, desserts and oceans, which would stop mammals, and they can move much faster than the wingless hosts. Birds can potentially transport tick-borne pathogens by transporting infected ticks, by being infected with tick-borne pathogens and transmit the pathogens to the ticks, and possibly act as hosts for transfer of pathogens between ticks through co-feeding. Knowledge of the bird migration routes and of the spatial distribution of tick species and tick-borne pathogens is crucial for understanding the possible impact of birds as spreaders of ticks and tick-borne pathogens. Successful colonization of new tick species or introduction of new tick-borne pathogens will depend on suitable climate, vegetation and hosts. Although it has never been demonstrated that a new tick species, or a new tick pathogen, actually has been established in a new locality after being seeded there by birds, evidence strongly suggests that this could occur.

  5. Transport of ixodid ticks and tick-borne pathogens by migratory birds

    PubMed Central

    Hasle, Gunnar

    2013-01-01

    Birds, particularly passerines, can be parasitized by Ixodid ticks, which may be infected with tick-borne pathogens, like Borrelia spp., Babesia spp., Anaplasma, Rickettsia/Coxiella, and tick-borne encephalitis virus. The prevalence of ticks on birds varies over years, season, locality and different bird species. The prevalence of ticks on different species depends mainly on the degree of feeding on the ground. In Europe, the Turdus spp., especially the blackbird, Turdus merula, appears to be most important for harboring ticks. Birds can easily cross barriers, like fences, mountains, glaciers, desserts and oceans, which would stop mammals, and they can move much faster than the wingless hosts. Birds can potentially transport tick-borne pathogens by transporting infected ticks, by being infected with tick-borne pathogens and transmit the pathogens to the ticks, and possibly act as hosts for transfer of pathogens between ticks through co-feeding. Knowledge of the bird migration routes and of the spatial distribution of tick species and tick-borne pathogens is crucial for understanding the possible impact of birds as spreaders of ticks and tick-borne pathogens. Successful colonization of new tick species or introduction of new tick-borne pathogens will depend on suitable climate, vegetation and hosts. Although it has never been demonstrated that a new tick species, or a new tick pathogen, actually has been established in a new locality after being seeded there by birds, evidence strongly suggests that this could occur. PMID:24058903

  6. Ability of successful attack in two species of ixodid ticks (Acari: Ixodidae) as a manifestation of their aggressiveness.

    PubMed

    Uspensky, I

    1993-09-01

    Patterns of attacking hosts by two closely related species of ixodid ticks (Ixodes persulcatus and I. ricinus) were compared in parallel field tests. The ability of active unfed adults of both sexes to adhere to a flannel flag dragged over grass vegetation and to remain on the flag during this process were estimated. The tests were conducted under two temperature conditions, 6-10 degrees C and 17-22 degrees C. In all test versions, adults of I. persulcatus were more successful both in adhering to the flag and in remaining on it. There were no consistent differences between males and females of the same species. The results demonstrated a differing ability of successful attack in both tick species. This ability is a complex derivative of the tick activity and aggressiveness. An attempt is made to analyse the latter phenomenon, which is considered as a general one for all bloodsucking arthropods. The aggressiveness of arthropods should be taken into account as one of the leading factors influencing the sampling results.

  7. Species composition and abundance of Brevipalpus spp. on different citrus species in Mexican orchards.

    PubMed

    Salinas-Vargas, D; Santillán-Galicia, M T; Valdez-Carrasco, J; Mora-Aguilera, G; Atanacio-Serrano, Y; Romero-Pescador, P

    2013-08-01

    We studied the abundance of Brevipalpus spp. in citrus orchards in the Mexican states of Yucatan, Quintana Roo and Campeche. Mites were collected from 100 trees containing a mixture of citrus species where sweet orange was always the main species. Eight collections were made at each location from February 2010 to February 2011. Mites from the genus Brevipalpus were separated from other mites surveyed and their abundance and relationships with the different citrus species were quantified throughout the collection period. A subsample of 25% of the total Brevipalpus mites collected were identified to species level and the interaction of mite species and citrus species were described. Brevipalpus spp. were present on all collection dates and their relative abundance was similar on all citrus species studies. The smallest number of mites collected was during the rainy season. Brevipalpus phoenicis (Geijskes) and Brevipalpus californicus (Banks) were the only two species present and they were found in all locations except Campeche, where only B. phoenicis was present. Yucatan and Campeche are at greater risk of leprosis virus transmission than Quintana Roo because the main vector, B. phoenicis, was more abundant than B. californicus. The implications of our results for the design of more accurate sampling and control methods for Brevipalpus spp. are discussed.

  8. Passive surveillance in Maine, an area emergent for tick-borne diseases.

    PubMed

    Rand, Peter W; Lacombe, Eleanor H; Dearborn, Richard; Cahill, Bruce; Elias, Susan; Lubelczyk, Charles B; Beckett, Geoff A; Smith, Robert P

    2007-11-01

    In 1989, a free-of-charge, statewide tick identification program was initiated in Maine, 1 yr after the first Ixodes scapularis Say (=I. dammini Spielman, Clifford, Piesman & Corwin) ticks were reported in the state. This article summarizes data from 18 continuous years of tick submissions during which >24,000 ticks of 14 species were identified. Data provided include tick stage, degree of engorgement, seasonal abundance, geographical location, host, and age of the person from whom the tick was removed. Maps depict the distributions of the three major species submitted. I. scapularis emerged first along the coast, and then it advanced inland up major river valleys, Dermacentor variabilis Say slowly expanded centrifugally from where it was initially reported in southwestern Maine, and the distribution of long-established Ixodes cookei Packard remained unchanged. Submissions of nymphal I. scapularis closely correlated with reported Lyme diseases cases at the county level. Annual fluctuations of nymphal submissions in Maine correlated with those of Lyme disease cases for New England, supporting the possibility of a regional influence on tick abundance. More ticks were removed from people < or =14 and > or =30 yr of age, and their degree of engorgement was greatest in people < or =20 yr of age and progressively increased in people > or =30 yr of age. This study demonstrates the usefulness and potential of tick identification programs.

  9. Metagenomic abundance estimation and diagnostic testing on species level

    PubMed Central

    Lindner, Martin S.; Renard, Bernhard Y.

    2013-01-01

    One goal of sequencing-based metagenomic community analysis is the quantitative taxonomic assessment of microbial community compositions. In particular, relative quantification of taxons is of high relevance for metagenomic diagnostics or microbial community comparison. However, the majority of existing approaches quantify at low resolution (e.g. at phylum level), rely on the existence of special genes (e.g. 16S), or have severe problems discerning species with highly similar genome sequences. Yet, problems as metagenomic diagnostics require accurate quantification on species level. We developed Genome Abundance Similarity Correction (GASiC), a method to estimate true genome abundances via read alignment by considering reference genome similarities in a non-negative LASSO approach. We demonstrate GASiC’s superior performance over existing methods on simulated benchmark data as well as on real data. In addition, we present applications to datasets of both bacterial DNA and viral RNA source. We further discuss our approach as an alternative to PCR-based DNA quantification. PMID:22941661

  10. Habitat and Vegetation Variables Are Not Enough When Predicting Tick Populations in the Southeastern United States.

    PubMed

    Trout Fryxell, R T; Moore, J E; Collins, M D; Kwon, Y; Jean-Philippe, S R; Schaeffer, S M; Odoi, A; Kennedy, M; Houston, A E

    2015-01-01

    Two tick-borne diseases with expanding case and vector distributions are ehrlichiosis (transmitted by Amblyomma americanum) and rickettiosis (transmitted by A. maculatum and Dermacentor variabilis). There is a critical need to identify the specific habitats where each of these species is likely to be encountered to classify and pinpoint risk areas. Consequently, an in-depth tick prevalence study was conducted on the dominant ticks in the southeast. Vegetation, soil, and remote sensing data were used to test the hypothesis that habitat and vegetation variables can predict tick abundances. No variables were significant predictors of A. americanum adult and nymph tick abundance, and no clustering was evident because this species was found throughout the study area. For A. maculatum adult tick abundance was predicted by NDVI and by the interaction between habitat type and plant diversity; two significant population clusters were identified in a heterogeneous area suitable for quail habitat. For D. variabilis no environmental variables were significant predictors of adult abundance; however, D. variabilis collections clustered in three significant areas best described as agriculture areas with defined edges. This study identified few landscape and vegetation variables associated with tick presence. While some variables were significantly associated with tick populations, the amount of explained variation was not useful for predicting reliably where ticks occur; consequently, additional research that includes multiple sampling seasons and locations throughout the southeast are warranted. This low amount of explained variation may also be due to the use of hosts for dispersal, and potentially to other abiotic and biotic variables. Host species play a large role in the establishment, maintenance, and dispersal of a tick species, as well as the maintenance of disease cycles, dispersal to new areas, and identification of risk areas.

  11. Habitat and Vegetation Variables Are Not Enough When Predicting Tick Populations in the Southeastern United States

    PubMed Central

    Trout Fryxell, R. T.; Moore, J. E.; Collins, M. D.; Kwon, Y.; Jean-Philippe, S. R.; Schaeffer, S. M.; Odoi, A.; Kennedy, M.; Houston, A. E.

    2015-01-01

    Two tick-borne diseases with expanding case and vector distributions are ehrlichiosis (transmitted by Amblyomma americanum) and rickettiosis (transmitted by A. maculatum and Dermacentor variabilis). There is a critical need to identify the specific habitats where each of these species is likely to be encountered to classify and pinpoint risk areas. Consequently, an in-depth tick prevalence study was conducted on the dominant ticks in the southeast. Vegetation, soil, and remote sensing data were used to test the hypothesis that habitat and vegetation variables can predict tick abundances. No variables were significant predictors of A. americanum adult and nymph tick abundance, and no clustering was evident because this species was found throughout the study area. For A. maculatum adult tick abundance was predicted by NDVI and by the interaction between habitat type and plant diversity; two significant population clusters were identified in a heterogeneous area suitable for quail habitat. For D. variabilis no environmental variables were significant predictors of adult abundance; however, D. variabilis collections clustered in three significant areas best described as agriculture areas with defined edges. This study identified few landscape and vegetation variables associated with tick presence. While some variables were significantly associated with tick populations, the amount of explained variation was not useful for predicting reliably where ticks occur; consequently, additional research that includes multiple sampling seasons and locations throughout the southeast are warranted. This low amount of explained variation may also be due to the use of hosts for dispersal, and potentially to other abiotic and biotic variables. Host species play a large role in the establishment, maintenance, and dispersal of a tick species, as well as the maintenance of disease cycles, dispersal to new areas, and identification of risk areas. PMID:26656122

  12. Species distribution and detection of Crimean Congo Hemorrhagic Fever Virus (CCHFV) in field-collected ticks in Ankara Province, Central Anatolia, Turkey.

    PubMed

    Hekimoglu, Olcay; Ozer, Nurdan; Ergunay, Koray; Ozkul, Aykut

    2012-01-01

    Ticks may act as vectors for a number of infectious diseases including Crimean Congo Hemorrhagic Fever (CCHF). The causative agent is Crimean Congo Hemorrhagic Fever Virus (CCHFV), a member of Bunyaviridae, causing extensive ecchymosis, visceral bleeding and hepatic dysfunction with a high fatality rate in the affected individuals. CCHF was initially recognized in Turkey in 2002 and the current number of reported cases exceeds 4,400. This study was conducted to confirm the presence of tick species established as potential CCHFV vectors and investigate CCHFV activity in ticks at Ankara province, Turkey's second most-densely populated province, where CCHF cases were demonstrated. A total of 1,196 adult ticks, collected from various animals and vegetation in 12 sites located in 5 counties of Ankara during April-July 2010 were identified to species level. Twenty-two tick pools from county K2 were also evaluated for the presence of CCHFV RNA via a one-step real-time RT-PCR assay and reactive results were further confirmed by an in house nested RT-PCR assay. Nine tick species were identified: Rhipicephalus bursa (44.9%), R. sanguineus (18.9%), R. turanicus (18.1%), Haemaphysalis parva (8.3%), Hyalomma marginatum marginatum (5.4%), H. aegyptium (1.4%), H. anatolicum excavatum (1.3%), Hae. punctata (0.3%) and Dermacentor marginatus (0.2%). A total of five tick pools (22.7%) were reactive in real-time and nested RT-PCR assays. The pools included R. bursa, H. m. marginatum and Hae. parva ticks, collected from mammal hosts from two villages in one county. This is the first documentation of CCHFV activity in ticks from Ankara province, which indicates requirement for detailed surveillance to predict high risk zones in the region.

  13. Survey of Ticks Collected from Tennessee Cattle and Their Pastures for Anaplasma and Ehrlichia Species.

    PubMed

    Pompo, K; Mays, S; Wesselman, C; Paulsen, D J; Fryxell, R T Trout

    2016-02-01

    Anaplasma marginale is the causative agent for bovine anaplasmosis (BA) and Ehrlichia ruminantium is the causative agent for heartwater, 2 devastating diseases of cattle. BA is common in the United States and frequently reported in western Tennessee cattle; however, cases of heartwater are not yet established in the continental United States. Because both pathogens are transmitted via the bites of infected ticks, the objective of this study was to survey cattle and pastures for ticks and for each pathogen. University of Tennessee AgResearch has 7 research and education centers (REC) located throughout the state at which they manage cattle. Ticks were collected from selected cattle (every fourth to sixth animal) and pastures (via dragging) associated with the herd from each REC during the summer of 2013. A total of 512 ticks were collected from cattle (n = 386) and pastures (n = 126) and were PCR-screened for Anaplasma and Ehrlichia using genus-specific primers. Collections consisted of 398 (77.7%) Amblyomma americanum, 84 (16.4%) Amblyomma maculatum, and 30 (5.9%) Dermacentor variabilis. Ticks were not recovered from pastures or cattle east of the Tennessee Plateau. The North American vectors for An. marginale and E. ruminantium were identified (D. variabilis and A. maculatum, respectively), but neither pathogen was recovered. A large proportion of ticks were collected from cattle and, of these, a majority were attached to their host (compared to questing on their host or engorged on the host). Four A. americanum were positive for Ehrlichia spp. (Ehrlichia ewingii, Ehrlichia chaffeensis, and Panola Mountain Ehrlichia), all in western Tennessee. With the identification of a few Ehrlichia infections in cattle-associated ticks and current A. marginale rates in Tennessee beef cattle nearing 11%, additional research is needed to establish baseline tick, Anaplasma, and Ehrlichia data for future management studies.

  14. Ticks collected from humans, domestic animals, and wildlife in Yucatan, Mexico.

    PubMed

    Rodríguez-Vivas, R I; Apanaskevich, D A; Ojeda-Chi, M M; Trinidad-Martínez, I; Reyes-Novelo, E; Esteve-Gassent, M D; Pérez de León, A A

    2016-01-15

    Domestic animals and wildlife play important roles as reservoirs of zoonotic pathogens that are transmitted to humans by ticks. Besides their role as vectors of several classes of microorganisms of veterinary and public health relevance, ticks also burden human and animal populations through their obligate blood-feeding habit. It is estimated that in Mexico there are around 100 tick species belonging to the Ixodidae and Argasidae families. Information is lacking on tick species that affect humans, domestic animals, and wildlife through their life cycle. This study was conducted to bridge that knowledge gap by inventorying tick species that infest humans, domestic animals and wildlife in the State of Yucatan, Mexico. Amblyomma ticks were observed as euryxenous vertebrate parasites because they were found parasitizing 17 animal species and human. Amblyomma mixtum was the most eryxenous species found in 11 different animal species and humans. Both A. mixtum and A. parvum were found parasitizing humans. Ixodes near affinis was the second most abundant species parasitizing six animal species (dogs, cats, horses, white-nosed coati, white-tail deer and black vulture) and was found widely across the State of Yucatan. Ixodid tick populations may increase in the State of Yucatan with time due to animal production intensification, an increasing wildlife population near rural communities because of natural habitat reduction and fragmentation. The diversity of ticks across host taxa documented here highlights the relevance of ecological information to understand tick-host dynamics. This knowledge is critical to inform public health and veterinary programs for the sustainable control of ticks and tick-borne diseases.

  15. Comparative analysis of the roles of Ixodes persulcatus and I. trianguliceps ticks in natural foci of ixodid tick-borne borrelioses in the Middle Urals, Russia.

    PubMed

    Korenberg, Edward I; Kovalevskii, Yurii V; Gorelova, Natalya B; Nefedova, Valentina V

    2015-04-01

    Long-term studies on natural foci of ixodid tick-borne borrelioses (ITBB) have been performed in Chusovskoi district of Perm region, the Middle Urals, where the vectors of these infections are represented by two ixodid tick species: the taiga tick Ixodes persulcatus and many times less abundant vole tick I. trianguliceps. Over 10 years, more than 6000 half-engorged ticks were collected from small forest mammals using the standard procedure, and 1027 I. persulcatus and 1142 I. trianguliceps ticks, individually or in pools, were used to inoculate BSK-2 medium. As a result, 199 Borrelia isolates were obtained. Among them, 177 isolates were identified, and the rrf(5S)-rrl(23S) intergenic spacer sequence was determined in 57 isolates. The prevalence of Borrelia infection in I. persulcatus larvae and nymphs averaged 31.0 and 53.3%, while that in I. trianguliceps larvae, nymphs, and adult ticks was five to ten times lower: 2.6, 10.2, and 8.1%, respectively. Each of the two tick species was found to carry both ITBB agents circulating in the Middle Ural foci (Borrelia garinii and B. afzelii), but the set of genogroups and genovariants of these spirochetes in I. trianguliceps proved to be far less diverse. According to the available data, this tick, compared to I. persulcatus, is generally less susceptible to Borrelia infection (especially by B. afzelii). Taking into account of its relatively low abundance, it appears that I. trianguliceps cannot seriously influence the course of epizootic process in ITBB foci of the study region, whereas highly abundant I. persulcatus with the high level of Borrelia infection is obviously a key component of these parasitic systems. A similar situation may well be typical for the entire geographic range shared by the two tick species.

  16. SPECIES-ABUNDANCE-BIOMASS RESPONSES BY ESTUARINE MACROBENTHOS TO SEDIMENT CHEMICAL CONTAMINATION.

    EPA Science Inventory

    Macrobenthic community responses can be measured through concerted changes in univariate metrics, including species richness, total abundance, and total biomass. The classic model of pollution effects on marine macroinvertebrate communities recognizes that species/abundance/bioma...

  17. Fuel breaks affect nonnative species abundance in Californian plant communities

    USGS Publications Warehouse

    Merriam, K.E.; Keeley, J.E.; Beyers, J.L.

    2006-01-01

    We evaluated the abundance of nonnative plants on fuel breaks and in adjacent untreated areas to determine if fuel treatments promote the invasion of nonnative plant species. Understanding the relationship between fuel treatments and nonnative plants is becoming increasingly important as federal and state agencies are currently implementing large fuel treatment programs throughout the United States to reduce the threat of wildland fire. Our study included 24 fuel breaks located across the State of California. We found that nonnative plant abundance was over 200% higher on fuel breaks than in adjacent wildland areas. Relative nonnative cover was greater on fuel breaks constructed by bulldozers (28%) than on fuel breaks constructed by other methods (7%). Canopy cover, litter cover, and duff depth also were significantly lower on fuel breaks constructed by bulldozers, and these fuel breaks had significantly more exposed bare ground than other types of fuel breaks. There was a significant decline in relative nonnative cover with increasing distance from the fuel break, particularly in areas that had experienced more numerous fires during the past 50 years, and in areas that had been grazed. These data suggest that fuel breaks could provide establishment sites for nonnative plants, and that nonnatives may invade surrounding areas, especially after disturbances such as fire or grazing. Fuel break construction and maintenance methods that leave some overstory canopy and minimize exposure of bare ground may be less likely to promote nonnative plants. ?? 2006 by the Ecological Society of America.

  18. Astrochem: Abundances of chemical species in the interstellar medium

    NASA Astrophysics Data System (ADS)

    Maret, Sébastien; Bergin, Edwin A.

    2015-07-01

    Astrochem computes the abundances of chemical species in the interstellar medium, as function of time. It studies the chemistry in a variety of astronomical objects, including diffuse clouds, dense clouds, photodissociation regions, prestellar cores, protostars, and protostellar disks. Astrochem reads a network of chemical reactions from a text file, builds up a system of kinetic rates equations, and solves it using a state-of-the-art stiff ordinary differential equation (ODE) solver. The Jacobian matrix of the system is computed implicitly, so the resolution of the system is extremely fast: large networks containing several thousands of reactions are usually solved in a few seconds. A variety of gas phase process are considered, as well as simple gas-grain interactions, such as the freeze-out and the desorption via several mechanisms (thermal desorption, cosmic-ray desorption and photo-desorption). The computed abundances are written in a HDF5 file, and can be plotted in different ways with the tools provided with Astrochem. Chemical reactions and their rates are written in a format which is meant to be easy to read and to edit. A tool to convert the chemical networks from the OSU and KIDA databases into this format is also provided. Astrochem is written in C, and its source code is distributed under the terms of the GNU General Public License (GPL).

  19. An extensive comparison of species-abundance distribution models

    PubMed Central

    Baldridge, Elita; Harris, David J.; Xiao, Xiao

    2016-01-01

    A number of different models have been proposed as descriptions of the species-abundance distribution (SAD). Most evaluations of these models use only one or two models, focus on only a single ecosystem or taxonomic group, or fail to use appropriate statistical methods. We use likelihood and AIC to compare the fit of four of the most widely used models to data on over 16,000 communities from a diverse array of taxonomic groups and ecosystems. Across all datasets combined the log-series, Poisson lognormal, and negative binomial all yield similar overall fits to the data. Therefore, when correcting for differences in the number of parameters the log-series generally provides the best fit to data. Within individual datasets some other distributions performed nearly as well as the log-series even after correcting for the number of parameters. The Zipf distribution is generally a poor characterization of the SAD. PMID:28028483

  20. Daughter Species Abundances in Comet C/2014 Q2 (Lovejoy)

    NASA Astrophysics Data System (ADS)

    McKay, Adam; Cochran, Anita; Dello Russo, Neil; Kelley, Michael

    2015-11-01

    We present analysis of high spectral resolution optical spectra of C/2014 Q2 (Lovejoy) acquired with the Tull Coude spectrometer on the 2.7-meter Harlan J. Smith Telescope at McDonald Observatory and the ARCES spectrometer mounted on the 3.5-meter Astrophysical Research Consortium Telescope at Apache Point Observatory. Both Tull Coude and ARCES provide high spectral resolution (R=30,000-60,000) and a large spectral range of approximately 3500-10000 Angstroms. We obtained two observation epochs, one in February 2015 at a heliocentric distance of 1.3 AU, and another in May 2015 at a heliocentric distance of 1.9 AU. Another epoch in late August 2015 at a heliocentric distance of 3.0 AU is scheduled. We will present production rates of the daughter species CN, C3, CH, C2, and NH2. We will also present H2O production rates derived from the [OI]6300 emission, as well as measurements of the flux ratio of the [OI]5577 Angstrom line to the sum of the [OI]6300 and [OI]6364 Angstrom lines (sometimes referred to as the oxygen line ratio). This ratio is indicative of the CO2 abundance of the comet. As we have observations at several heliocentric distances, we will examine how production rates and mixing ratios of the various species change with heliocentric distance. We will compare our oxygen line measurements to observations of CO2 made with Spitzer, as well as our other daughter species observations to those of candidate parent molecules made at IR wavelengths.

  1. Taxonomic and phylogenetic relationships between neotropical species of ticks from genus Amblyomma (Acari: Ixodidae) inferred from second internal transcribed spacer sequences of rDNA.

    PubMed

    Marrelli, M T; Souza, L F; Marques, R C; Labruna, M B; Matioli, S R; Tonon, A P; Ribolla, P E M; Marinotti, O; Schumaker, T T S

    2007-03-01

    The accurate specific identification of ticks is essential for the study, control and prevention of tick-borne diseases. Herein, we determined ribosomal nucleotide sequences of the second internal transcribed spacer (ITS2) of 15 Neotropical hard tick species of the genus Amblyomma Koch found in Brazil. Most of the studied ticks accidentally parasite humans and potentially act as vectors of zoonoses. Lengths of the ITS2 sequences ranged from 956 to 1,207 bp, whereas GC content varied from 62.4 to 66.9%. A matrix of ITS2 divergence was calculated with the ITS2 sequence data obtained showing divergence levels varying from 1.5 to 28.8%. The analysis indicated that this molecular marker can be useful for Amblyomma-specific identification. Phylogenetic inferences based on the ITS2 sequences were used to assess some issues in subgenus taxonomy.

  2. Molecular detection of Rickettsia rhipicephali and other spotted fever group Rickettsia species in Amblyomma ticks infesting wild birds in the state of Minas Gerais, Brazil.

    PubMed

    Zeringóta, Viviane; Maturano, Ralph; Luz, Hermes Ribeiro; Senra, Tatiane Oliveira Souza; Daemon, Erik; Faccini, João Luiz Horacio; McIntosh, Douglas

    2017-01-01

    The current study evaluated parasitism of wild birds by ticks in a fragment of Atlantic Forest in the state of Minas Gerais, Brazil, and examined the ticks for rickettsial agents. Birds were captured during 2014 and 2015 and ticks were identified by sequencing fragments of the 16S and 12S ribosomal DNA. Among 260 birds representing 19 families and 52 species, a total of 69 (26.5%) were found to be infested by larvae (LL) and/or nymphs (NN) of Amblyomma longirostre (Koch, 1844) (45 LL, 4 NN), Amblyomma calcaratum Neumann, 1899 (9 LL, 15 NN), Amblyomma nodosum Neumann, 1899 (2 NN), Amblyomma parkeri Fonseca and Aragão, 1952 (21 LL), Amblyomma sp. haplotype Nazaré (77 LL), and Haemaphysalis leporispalustris (Packard, 1869) (17 LL, 1 NN). The use of PCR and sequencing of the rickettsial genes gltA, htrA, ompA and ompB, revealed the presence of "Candidatus Rickettsia amblyommii" in A. longirostre (13/49; 26%) and Rickettsia parkeri (strain ApPR) in both A. parkeri (1/21; 5%) and haplotype Nazaré (42/77; 55%) ticks. In addition, we detected Rickettsia rhipicephali in 31 (40%) of the 77 haplotype Nazaré ticks. This is the first record of this rickettsial agent in a species of the genus Amblyomma. The pathogenic potential of this bacterium is undetermined, but the unprecedented association with Amblyomma ticks may represent a cause for concern for public and/or animal health.

  3. Rickettsiaceae and Anaplasmataceae infections in Ixodes ricinus ticks from urban and natural forested areas of Poland

    PubMed Central

    2014-01-01

    Background Ixodes ricinus is a major vector for a range of microbial pathogens and the most prevalent and widely distributed tick species on the European continent, occurring in both natural and urban habitats. Nevertheless, little is known about the relative density of ticks in these two ecologically distinct habitats and the diversity of tick-borne pathogens that they carry. Methods We compared densities of questing I. ricinus nymphs and adults in urban and natural habitats in Central and Northeastern Poland, assessed the prevalence and rate of co-infection with A. phagocytophilum, Rickettsia, Ehrlichia and ‘Ca. Neoehrlichia spp.’ in ticks, and compared the diversity of tick-borne pathogens using molecular assays (PCR). Results Of the 1325 adults and nymphs, 6.2% were infected with at least one pathogen, with 4.4%, 1.7% and less than 0.5% being positive for the DNA of Rickettsia spp., A. phagocytophilum, Ehrlichia spp. and Ca. N. mikurensis, respectively. Although tick abundance was higher in natural habitats, the prevalence of the majority of pathogens was higher in urban forested areas. Conclusion We conclude that: (i) zoonotic genetic variants of A. phagocytophilum are widely distributed in the Polish tick population, (ii) although the diversity of tick borne pathogens was higher in natural habitats, zoonotic species/strains were detected only in urban forests, (iii) and we provide the first description of Ca. N. mikurensis infections in ticks in Poland. PMID:24661311

  4. Parasites of domestic and wild animals in South Africa. XXII. Ixodid ticks on domestic dogs and on wild carnivores.

    PubMed

    Horak, I G; Guillarmod, A J; Moolman, L C; de Vos, V

    1987-12-01

    Ixodid ticks were collected from 4 dogs on smallholdings near Grahamstown, eastern Cape Province, on 1 or more occasions each week for periods ranging from 9-36 months. Fourteen tick species were recovered and the seasonal abundance of adult Haemaphysalis leachi and adult Rhipicephalus simus was determined. Complete collections of ticks were made from 50 caracals (Felis caracal) in the Cradock, Graaff-Reinet and Southwell regions in the eastern Cape Province. The animals from Cradock and Graaff-Reinet harboured 13 ixodid tick species. The caracals from Southwell were infested with 11 tick species and the seasonal abundance of Ixodes pilosus on these animals was determined. A small-spotted genet (Genetta genetta), 1 bat-eared fox (Otocyon megalotis), 1 aardwolf (Proteles cristatus) and 6 black-backed jackal (Canis mesomelas) from various localities in the eastern Cape Province were examined for ticks and 9 species were collected. Complete tick collections were made from a side-striped jackal (Canis adustus), 2 wild dogs (Lycaon pictus), a spotted hyaena (Crocuta crocuta), a several (Felis serval), 2 African civets (Civettictis civetta), 2 leopards (Panthera pardus) and a lion (Panthera leo) in the Kruger National Park in the north-eastern Transvaal. Twelve ixodid tick specis were recovered from these animals.

  5. Developing Anti-tick Vaccines.

    PubMed

    Rodríguez-Mallon, Alina

    2016-01-01

    Ticks are responsible for the transmission of viral, bacterial, and protozoal diseases of man and animals and also produce significant economic losses to cattle industry. The use of acaricides constitutes a major component of integrated tick control strategies. However, this is accompanied by the selection of acaricide-resistant ticks and contamination of environment and milk and meat products with drug residues. These issues highlight the need for alternative approaches to control tick infestations and have triggered the search for tick protective antigens for vaccine development. Vaccination as a tick control method has been practiced since the introduction of TickGARD and Gavac that were developed using the midgut glycoprotein Bm86 as antigen. Gavac within integrated tick management systems has proven to reduce the number of acaricidal applications per year that are required to control some strains of R. microplus ticks in different geographical regions. Nevertheless, it has limited or no efficacy against other tick species. These issues have stimulated research for additional tick protective antigens with critical functions in the tick. This chapter presents methodologies for the design and test of molecules as antigens against ticks. Considerations about different methods for the tick control compared to the immunological methods, the desirable characteristics for an anti-tick vaccine and the obstacles encountered for developing this kind of vaccines are discussed. Detailed methodologies for the establishment of a biological model to test new molecules as immunogens against ticks and to perform challenge trials with this model are presented. General considerations in the efficacy calculation for any anti-tick vaccine are also discussed.

  6. Fibrinogen-related proteins in ixodid ticks

    PubMed Central

    2011-01-01

    Background Fibrinogen-related proteins with lectin activity are believed to be part of the tick innate immune system. Several fibrinogen-related proteins have been described and characterised mainly on the basis of their cDNA sequences while direct biochemical evidence is missing. One of them, the haemolymph lectin Dorin M from the tick Ornithodoros moubata was isolated and characterised in more depth. Results Several fibrinogen-related proteins were detected in the haemolymph of ixodid ticks Dermacentor marginatus, Rhipicephalus appendiculatus, R. pulchellus, and R. sanguineus. These proteins were recognised by sera directed against the tick lectin Dorin M and the haemagglutination activity of the ticks R. appendiculatus and D. marginatus. Cross-reactivity of the identified proteins with antibodies against the fibrinogen domain of the human ficolin was also shown. The carbohydrate-binding ability of tick haemolymph was confirmed by haemagglutination activity assays, and this activity was shown to be inhibited by neuraminic acid and sialylated glycoproteins as well as by N-acetylated hexosamines. The fibrinogen-related proteins were shown to be glycosylated and they were localised in salivary glands, midguts, and haemocytes of D. marginatus. Hemelipoglycoprotein was also recognised by sera directed against the fibrinogen-related proteins in all three Rhipicephalus species as well as in D. marginatus. However, this protein does not contain the fibrinogen domain and thus, the binding possibly results from the structure similarity between hemelipoglycoprotein and the fibrinogen domain. Conclusions The presence of fibrinogen-related proteins was shown in the haemolymph of four tick species in high abundance. Reactivity of antibodies directed against ficolin or fibrinogen-related proteins with proteins which do not contain the fibrinogen domain points out the importance of sequence analysis of the identified proteins in further studies. Previously observed expression of

  7. Nellore cattle (Bos indicus) and ticks within the Brazilian Pantanal: ecological relationships.

    PubMed

    Ramos, Vanessa N; Piovezan, Ubiratan; Franco, Ana Helena A; Rodrigues, Vinicius S; Nava, Santiago; Szabó, Matias P J

    2016-02-01

    Pantanal is a huge floodplain mostly in Brazil, and its main economic activity is extensive cattle raising, in farms characterized by an extremely wildlife-rich environment. We herein describe tick infestations of cattle and of the natural environment in Pantanal of Nhecolândia in Brazil, at areas with and without cattle during both dry and wet seasons. Environmental sampling resulted in three tick species: Amblyomma sculptum (423 nymphs and 518 adults), Amblyomma parvum (7 nymphs and 129 adults), Amblyomma ovale (3 adults) as well as three clusters and two individuals of Amblyomma sp. larvae. A significantly higher number of adult A. sculptum ticks was found in areas with cattle in the wet season. From 106 examinations of bovines 1710 ticks from three species were collected: Rhipicephalus microplus (55.7% of the total), A. sculptum (38%) and A. parvum (4.1%), as well as 32 Amblyomma sp. larvae. A significant similarity was found between Amblyomma tick fauna from environment and on cattle during both seasons. All A. sculptum females on bovines were flat whereas many of A. parvum females and A. sculptum nymphs were engorging. Although R. microplus was the most abundant tick species on cattle, overall highest tick prevalence on bovines in the dry season was of A. sculptum nymphs. Lack of R. microplus in environmental sampling, relationship between cattle and increase in adult A. sculptum numbers in the environment as well as suitability of bovine for the various tick species are discussed.

  8. Commonly rare and rarely common: comparing population abundance of invasive and native aquatic species.

    PubMed

    Hansen, Gretchen J A; Vander Zanden, M Jake; Blum, Michael J; Clayton, Murray K; Hain, Ernie F; Hauxwell, Jennifer; Izzo, Marit; Kornis, Matthew S; McIntyre, Peter B; Mikulyuk, Alison; Nilsson, Erika; Olden, Julian D; Papeş, Monica; Sharma, Sapna

    2013-01-01

    Invasive species are leading drivers of environmental change. Their impacts are often linked to their population size, but surprisingly little is known about how frequently they achieve high abundances. A nearly universal pattern in ecology is that species are rare in most locations and abundant in a few, generating right-skewed abundance distributions. Here, we use abundance data from over 24,000 populations of 17 invasive and 104 native aquatic species to test whether invasive species differ from native counterparts in statistical patterns of abundance across multiple sites. Invasive species on average reached significantly higher densities than native species and exhibited significantly higher variance. However, invasive and native species did not differ in terms of coefficient of variation, skewness, or kurtosis. Abundance distributions of all species were highly right skewed (skewness>0), meaning both invasive and native species occurred at low densities in most locations where they were present. The average abundance of invasive and native species was 6% and 2%, respectively, of the maximum abundance observed within a taxonomic group. The biological significance of the differences between invasive and native species depends on species-specific relationships between abundance and impact. Recognition of cross-site heterogeneity in population densities brings a new dimension to invasive species management, and may help to refine optimal prevention, containment, control, and eradication strategies.

  9. Prevalence, diversity, and load of Borrelia species in ticks that have fed on humans in regions of Sweden and Åland Islands, Finland with different Lyme borreliosis incidences.

    PubMed

    Wilhelmsson, Peter; Lindblom, Pontus; Fryland, Linda; Ernerudh, Jan; Forsberg, Pia; Lindgren, Per-Eric

    2013-01-01

    The incidence of Lyme borreliosis (LB) in a region may reflect the prevalence of Borrelia in the tick population. Our aim was to investigate if regions with different LB incidences can be distinguished by studying the prevalence and diversity of Borrelia species in their respective tick populations. The Borrelia load in a feeding tick increases with the duration of feeding, which may facilitate a transmission of Borrelia Spirochetes from tick to host. Therefore, we also wanted to investigate how the Borrelia load in ticks that have fed on humans varies with the duration of tick feeding. During 2008 and 2009, ticks that had bitten humans were collected from four regions of Sweden and Finland, regions with expected differences in LB incidence. The duration of tick feeding was estimated and Borrelia were detected and quantified by a quantitative PCR assay followed by species determination. Out of the 2,154 Ixodes ricinus ticks analyzed, 26% were infected with Borrelia and seven species were identified. B. spielmanii was detected for the first time in the regions. The tick populations collected from the four regions exhibited only minor differences in both prevalence and diversity of Borrelia species, indicating that these variables alone cannot explain the regions' different LB incidences. The number of Borrelia cells in the infected ticks ranged from fewer than ten to more than a million. We also found a lower number of Borrelia cells in adult female ticks that had fed for more than 36 hours, compared to the number of Borrelia cells found in adult female ticks that had fed for less than 36 hours.

  10. RELATIONSHIPS OF ALIEN PLANT SPECIES ABUNDANCE TO RIPARIAN VEGETATION, ENVIRONMENT, AND DISTURBANCE

    EPA Science Inventory

    Riparian ecosystems are often invaded by alien species. We evaluated vegetation, environment, and disturbance conditions and their interrelationships with alien species abundance along reaches of 29 streams in eastern Oregon, USA. Using flexible-BETA clustering, indicator species...

  11. Plant Trait-Species Abundance Relationships Vary with Environmental Properties in Subtropical Forests in Eastern China

    PubMed Central

    Yan, En-Rong; Yang, Xiao-Dong; Chang, Scott X.; Wang, Xi-Hua

    2013-01-01

    Understanding how plant trait-species abundance relationships change with a range of single and multivariate environmental properties is crucial for explaining species abundance and rarity. In this study, the abundance of 94 woody plant species was examined and related to 15 plant leaf and wood traits at both local and landscape scales involving 31 plots in subtropical forests in eastern China. Further, plant trait-species abundance relationships were related to a range of single and multivariate (PCA axes) environmental properties such as air humidity, soil moisture content, soil temperature, soil pH, and soil organic matter, nitrogen (N) and phosphorus (P) contents. At the landscape scale, plant maximum height, and twig and stem wood densities were positively correlated, whereas mean leaf area (MLA), leaf N concentration (LN), and total leaf area per twig size (TLA) were negatively correlated with species abundance. At the plot scale, plant maximum height, leaf and twig dry matter contents, twig and stem wood densities were positively correlated, but MLA, specific leaf area, LN, leaf P concentration and TLA were negatively correlated with species abundance. Plant trait-species abundance relationships shifted over the range of seven single environmental properties and along multivariate environmental axes in a similar way. In conclusion, strong relationships between plant traits and species abundance existed among and within communities. Significant shifts in plant trait-species abundance relationships in a range of environmental properties suggest strong environmental filtering processes that influence species abundance and rarity in the studied subtropical forests. PMID:23560114

  12. Modeling the Impact of Climate and Landscape on the Efficacy of White Tailed Deer Vaccination for Cattle Tick Control in Northeastern Mexico

    PubMed Central

    Estrada-Peña, Agustín; Carreón, Diana; Almazán, Consuelo; de la Fuente, José

    2014-01-01

    Cattle ticks are distributed worldwide and affect animal health and livestock production. White tailed deer (WTD) sustain and spread cattle tick populations. The aim of this study was to model the efficacy of anti-tick vaccination of WTD to control tick infestations in the absence of cattle vaccination in a territory where both host species coexist and sustain cattle tick populations. Agent-based models that included land cover/landscape properties (patch size, distances to patches) and climatic conditions were built in a GIS environment to simulate WTD vaccine effectiveness under conditions where unvaccinated cattle shared the landscape. Published and validated information on tick life cycle was used to build models describing tick mortality and developmental rates. Data from simulations were applied to a large territory in northeastern Mexico where cattle ticks are endemic and WTD and cattle share substantial portions of the habitat. WTD movements were simulated together with tick population dynamics considering the actual landscape and climatic features. The size of the vegetation patches and the distance between patches were critical for the successful control of tick infestations after WTD vaccination. The presence of well-connected, large vegetation patches proved essential for tick control, since the tick could persist in areas of highly fragmented habitat. The continued application of one yearly vaccination on days 1-70 for three years reduced tick abundance/animal/patch by a factor of 40 and 60 for R. annulatus and R. microplus, respectively when compared to non-vaccinated controls. The study showed that vaccination of WTD alone during three consecutive years could result in the reduction of cattle tick populations in northeastern Mexico. Furthermore, the results of the simulations suggested the possibility of using vaccines to prevent the spread and thus the re-introduction of cattle ticks into tick-free areas. PMID:25047078

  13. Spatial disaggregation of tick occurrence and ecology at a local scale as a preliminary step for spatial surveillance of tick-borne diseases: general framework and health implications in Belgium

    PubMed Central

    2013-01-01

    Background The incidence of tick-borne diseases is increasing in Europe. Sub national information on tick distribution, ecology and vector status is often lacking. However, precise location of infection risk can lead to better targeted prevention measures, surveillance and control. Methods In this context, the current paper compiled geolocated tick occurrences in Belgium, a country where tick-borne disease has received little attention, in order to highlight the potential value of spatial approaches and draw some recommendations for future research priorities. Results Mapping of 89,289 ticks over 654 sites revealed that ticks such as Ixodes ricinus and Ixodes hexagonus are largely present while Dermacentor reticulatus has a patchy distribution. Suspected hot spots of tick diversity might favor pathogen exchanges and suspected hot spots of I. ricinus abundance might increase human-vector contact locally. This underlines the necessity to map pathogens and ticks in detail. While I. ricinus is the main vector, I. hexagonus is a vector and reservoir of Borrelia burgdorferi s.l., which is active the whole year and is also found in urban settings. This and other nidiculous species bite humans less frequently, but seem to harbour pathogens. Their role in maintaining a pathogenic cycle within the wildlife merits investigation as they might facilitate transmission to humans if co-occurring with I. ricinus. Many micro-organisms are found abroad in tick species present in Belgium. Most have not been recorded locally but have not been searched for. Some are transmitted directly at the time of the bite, suggesting promotion of tick avoidance additionally to tick removal. Conclusion This countrywide approach to tick-borne diseases has helped delineate recommendations for future research priorities necessary to design public health policies aimed at spatially integrating the major components of the ecological cycle of tick-borne diseases. A systematic survey of tick species and

  14. Ixodes scapularis Tick Saliva Proteins Sequentially Secreted Every 24 h during Blood Feeding

    PubMed Central

    Pinto, Antônio F. M.; Moresco, James; Yates, John R.; da Silva Vaz, Itabajara; Mulenga, Albert

    2016-01-01

    Ixodes scapularis is the most medically important tick species and transmits five of the 14 reportable human tick borne disease (TBD) agents in the USA. This study describes LC-MS/MS identification of 582 tick- and 83 rabbit proteins in saliva of I. scapularis ticks that fed for 24, 48, 72, 96, and 120 h, as well as engorged but not detached (BD), and spontaneously detached (SD). The 582 tick proteins include proteases (5.7%), protease inhibitors (7.4%), unknown function proteins (22%), immunity/antimicrobial (2.6%), lipocalin (3.1%), heme/iron binding (2.6%), extracellular matrix/ cell adhesion (2.2%), oxidant metabolism/ detoxification (6%), transporter/ receptor related (3.2%), cytoskeletal (5.5%), and housekeeping-like (39.7%). Notable observations include: (i) tick saliva proteins of unknown function accounting for >33% of total protein content, (ii) 79% of proteases are metalloproteases, (iii) 13% (76/582) of proteins in this study were found in saliva of other tick species and, (iv) ticks apparently selectively inject functionally similar but unique proteins every 24 h, which we speculate is the tick's antigenic variation equivalent strategy to protect important tick feeding functions from host immune system. The host immune responses to proteins present in 24 h I. scapularis saliva will not be effective at later feeding stages. Rabbit proteins identified in our study suggest the tick's strategic use of host proteins to modulate the feeding site. Notably fibrinogen, which is central to blood clotting and wound healing, was detected in high abundance in BD and SD saliva, when the tick is preparing to terminate feeding and detach from the host. A remarkable tick adaptation is that the feeding lesion is completely healed when the tick detaches from the host. Does the tick concentrate fibrinogen at the feeding site to aide in promoting healing of the feeding lesion? Overall, these data provide broad insight into molecular mechanisms regulating different tick

  15. Common European birds are declining rapidly while less abundant species' numbers are rising.

    PubMed

    Inger, Richard; Gregory, Richard; Duffy, James P; Stott, Iain; Voříšek, Petr; Gaston, Kevin J

    2015-01-01

    Biodiversity is undergoing unprecedented global decline. Efforts to slow this rate have focused foremost on rarer species, which are at most risk of extinction. Less interest has been paid to more common species, despite their greater importance in terms of ecosystem function and service provision. How rates of decline are partitioned between common and less abundant species remains unclear. Using a 30-year data set of 144 bird species, we examined Europe-wide trends in avian abundance and biomass. Overall, avian abundance and biomass are both declining with most of this decline being attributed to more common species, while less abundant species showed an overall increase in both abundance and biomass. If overall avian declines are mainly due to reductions in a small number of common species, conservation efforts targeted at rarer species must be better matched with efforts to increase overall bird numbers, if ecological impacts of birds are to be maintained.

  16. Molecular detection of Anaplasma, Bartonella, and Borrelia species in ticks collected from migratory birds from Hong-do Island, Republic of Korea.

    PubMed

    Kang, Jun-Gu; Kim, Heung-Chul; Choi, Chang-Yong; Nam, Hyun-Young; Chae, Hee-Young; Chong, Sung-Tae; Klein, Terry A; Ko, Sungjin; Chae, Joon-Seok

    2013-04-01

    Bird migration is a recurring annual and seasonal event undertaken by more than 100 species of birds in the southeast Asian and northeast Palearctic regions that pass through or remain for short periods from April to May and September to November at Hong-do Island, Republic of Korea (ROK). A total of 212 ticks (40 Haemaphysalis flava, 12 H. longicornis, 146 Ixodes turdus, 13 I. nipponensis, and 1 I. ornithophila) were collected from 65/2,161 (3.0%) migratory birds consisting of 21 species that were captured from January, 2008, through December, 2009, as part of the Migratory Birds Center, Hong-do bird banding program for studying bird migration patterns. Adult ticks were assayed individually while larvae and nymphs were pooled (1-22 and 1-6 ticks per pool, respectively) into 31 and 65 pools, respectively. Ticks were assayed for zoonotic pathogens by PCR using 16S rRNA, heat shock protein (groEL), and internal transcribed spacer (ITS) gene primers to amplify genera specific for Anapalsma, Bartonella, and Borrelia PCR amplicons. Using the 16S rRNA-based nested PCR, A. phagocytophilum (n=1) was detected in I. nipponensis collected from Zoothera sibirica and A. bovis (n=1) was detected in I. turdus collected from Emberiza chrysophrys. Borrelia turdi 16S rRNA genes (n=3) were detected in I. turdus and I. nipponensis collected from Turdus pallidus and Zoothera aurea. Borrelia spp. 16S rRNA genes (n=4) were detected in Ixodes ticks collected from Emberiza tristrami, T. pallidus, and Z. aurea. The Bartonella grahamii ITS gene (n=1) was detected by nested PCR assay in I. turdus collected from Z. aurea. These results provide insight into the potential role of migratory birds in the dispersal of ticks and associated tick-borne pathogens throughout their ranges in Asia.

  17. Comparative Metagenomic Profiling of Symbiotic Bacterial Communities Associated with Ixodes persulcatus, Ixodes pavlovskyi and Dermacentor reticulatus Ticks.

    PubMed

    Kurilshikov, Alexander; Livanova, Natalya N; Fomenko, Nataliya V; Tupikin, Alexey E; Rar, Vera A; Kabilov, Marsel R; Livanov, Stanislav G; Tikunova, Nina V

    2015-01-01

    Ixodes persulcatus, Ixodes pavlovskyi, and Dermacentor reticulatus ticks inhabiting Western Siberia are responsible for the transmission of a number of etiological agents that cause human and animal tick-borne diseases. Because these ticks are abundant in the suburbs of large cities, agricultural areas, and popular tourist sites and frequently attack people and livestock, data regarding the microbiomes of these organisms are required. Using metagenomic 16S profiling, we evaluate bacterial communities associated with I. persulcatus, I. pavlovskyi, and D. reticulatus ticks collected from the Novosibirsk region of Russia. A total of 1214 ticks were used for this study. DNA extracted from the ticks was pooled according to tick species and sex. Sequencing of the V3-V5 domains of 16S rRNA genes was performed using the Illumina Miseq platform. The following bacterial genera were prevalent in the examined communities: Acinetobacter (all three tick species), Rickettsia (I. persulcatus and D. reticulatus) and Francisella (D. reticulatus). B. burgdorferi sensu lato and B. miyamotoi sequences were detected in I. persulcatus and I. pavlovskyi but not in D. reticulatus ticks. The pooled samples of all tick species studied contained bacteria from the Anaplasmataceae family, although their occurrence was low. DNA from A. phagocytophilum and Candidatus Neoehrlichia mikurensis was first observed in I. pavlovskyi ticks. Significant inter-species differences in the number of bacterial taxa as well as intra-species diversity related to tick sex were observed. The bacterial communities associated with the I. pavlovskyi ticks displayed a higher biodiversity compared with those of the I. persulcatus and D. reticulatus ticks. Bacterial community structure was also diverse across the studied tick species, as shown by permutational analysis of variance using the Bray-Curtis dissimilarity metric (p = 0.002). Between-sex variation was confirmed by PERMANOVA testing in I. persulcatus (p = 0

  18. First identification of Rickettsia helvetica in questing ticks from a French Northern Brittany Forest

    PubMed Central

    Paul, Richard E. L.; Bischoff, Emmanuel; Cote, Martine; Le Naour, Evelyne

    2017-01-01

    Tick-borne rickettsiae are considered to be emerging, but data about their presence in western Europe are scarce. Ixodes ricinus ticks, the most abundant and widespread tick species in western Europe, were collected and tested for the presence of several tick-borne pathogens in western France, a region never previously explored in this context. There was a high tick abundance with a mean of 4 females, 4.5 males, and 23.3 nymphs collected per hour per collector. Out of 622 tested ticks, specific PCR amplification showed the presence of tick symbionts as well as low prevalence of Borrelia burgdorferi (0.8%), Bartonella spp. (0.17%), and Anaplasma phagocytophilum (0.09%). The most prevalent pathogen was Rickettsia helvetica (4.17%). This is the first time that this bacteria has been detected in ticks in this region, and this result raises the possibility that bacteria other than those classically implicated may be involved in rickettsial diseases in western France. PMID:28248955

  19. Ticks and Tick-borne diseases in Ireland.

    PubMed

    Zintl, Annetta; Moutailler, Sara; Stuart, Peter; Paredis, Linda; Dutraive, Justine; Gonzalez, Estelle; O'Connor, Jack; Devillers, Elodie; Good, Barbara; OMuireagain, Colm; De Waal, Theo; Morris, Fergal; Gray, Jeremy

    2017-01-01

    Throughout Europe interest in tick-borne agents is increasing, particularly with regard to those that can cause human disease. The reason for this is the apparent rise in the incidence of many tick-borne diseases (TBD's). While there has never been a national survey of ticks or TBD's in Ireland, the trend here appears to be the reverse with a decline in the incidence of some agents seemingly associated with decreasing tick numbers particularly on agricultural land. In the absence of robust baseline data, however, this development cannot be confirmed. This review collates the limited information available from several dated published records on tick species and a small number of studies focused on certain TBD's. Some pilot data on tick density and TBD agents collected in 2016 are also presented. The aim is to explore the particular situation in Ireland with regard to ticks and TBD's and to provide a reference for future workers in the field.

  20. Modelling community dynamics based on species-level abundance models from detection/nondetection data

    USGS Publications Warehouse

    Yamaura, Yuichi; Royle, J. Andrew; Kuboi, Kouji; Tada, Tsuneo; Ikeno, Susumu; Makino, Shun'ichi

    2011-01-01

    1. In large-scale field surveys, a binary recording of each species' detection or nondetection has been increasingly adopted for its simplicity and low cost. Because of the importance of abundance in many studies, it is desirable to obtain inferences about abundance at species-, functional group-, and community-levels from such binary data. 2. We developed a novel hierarchical multi-species abundance model based on species-level detection/nondetection data. The model accounts for the existence of undetected species, and variability in abundance and detectability among species. Species-level detection/nondetection is linked to species- level abundance via a detection model that accommodates the expectation that probability of detection (at least one individuals is detected) increases with local abundance of the species. We applied this model to a 9-year dataset composed of the detection/nondetection of forest birds, at a single post-fire site (from 7 to 15 years after fire) in a montane area of central Japan. The model allocated undetected species into one of the predefined functional groups by assuming a prior distribution on individual group membership. 3. The results suggest that 15–20 species were missed in each year, and that species richness of communities and functional groups did not change with post-fire forest succession. Overall abundance of birds and abundance of functional groups tended to increase over time, although only in the winter, while decreases in detectabilities were observed in several species. 4. Synthesis and applications. Understanding and prediction of large-scale biodiversity dynamics partly hinge on how we can use data effectively. Our hierarchical model for detection/nondetection data estimates abundance in space/time at species-, functional group-, and community-levels while accounting for undetected individuals and species. It also permits comparison of multiple communities by many types of abundance-based diversity and similarity

  1. Fish and phytoplankton exhibit contrasting temporal species abundance patterns in a dynamic north temperate lake.

    PubMed

    Hansen, Gretchen J A; Carey, Cayelan C

    2015-01-01

    Temporal patterns of species abundance, although less well-studied than spatial patterns, provide valuable insight to the processes governing community assembly. We compared temporal abundance distributions of two communities, phytoplankton and fish, in a north temperate lake. We used both 17 years of observed relative abundance data as well as resampled data from Monte Carlo simulations to account for the possible effects of non-detection of rare species. Similar to what has been found in other communities, phytoplankton and fish species that appeared more frequently were generally more abundant than rare species. However, neither community exhibited two distinct groups of "core" (common occurrence and high abundance) and "occasional" (rare occurrence and low abundance) species. Both observed and resampled data show that the phytoplankton community was dominated by occasional species appearing in only one year that exhibited large variation in their abundances, while the fish community was dominated by core species occurring in all 17 years at high abundances. We hypothesize that the life-history traits that enable phytoplankton to persist in highly dynamic environments may result in communities dominated by occasional species capable of reaching high abundances when conditions allow. Conversely, longer turnover times and broad environmental tolerances of fish may result in communities dominated by core species structured primarily by competitive interactions.

  2. Influence of deer abundance on the abundance of questing adult Ixodes scapularis (Acari: Ixodidae)

    USGS Publications Warehouse

    Ginsberg, H.S.; Zhioua, E.

    1999-01-01

    Nymphal and adult Ixodes scapularis Say were sampled by flagging at 2 sites on a barrier island, Fire Island, NY, and at 2 sites on the nearby mainland. Nymphal densities did not differ consistently between island and mainland sites, but adult densities were consistently lower on the island. We tested whether lower adult densities on the island resulted from greater nymphal mortality on the island than the mainland, or whether adult ticks on the island were poorly sampled by flagging because they had attached abundantly to deer, which were common on Fire Island. Differential nymphal mortality on islands vs. mainland did not explain this difference in adult densities because survival of flat and engorged nymphs in enclosures was the same at island and mainland sites. Ticks were infected by parasitic wasps on the island and not the mainland, but the infection rate (4.3%) was too low to explain the difference in adult tick densities. In contrast, exclusion of deer by game fencing on Fire Island resulted in markedly increased numbers of adult ticks in flagging samples inside compared to samples taken outside the exclosures. Therefore, the scarcity of adult ticks in flagging samples on Fire Island resulted, at least in part, from the ticks being unavailable to flagging samples because they were on deer hosts. Differences in the densities of flagged ticks inside and outside the exclosures were used to estimate the percentage of questing adults on Fire Island that found deer hosts, excluding those that attached to other host species. Approximately 56% of these questing adult ticks found deer hosts in 1995 and 50% found deer hosts in 1996. Therefore, in areas where vertebrate hosts are highly abundant, large proportions of the questing tick population can find hosts. Moreover, comparisons of tick densities at different sites by flagging can potentially be biased by differences in host densities among sites.

  3. The influence of interspecific competition and host preference on the phylogeography of two African ixodid tick species.

    PubMed

    Cangi, Nídia; Horak, Ivan G; Apanaskevich, Dmitry A; Matthee, Sonja; das Neves, Luís C B G; Estrada-Peña, Agustín; Matthee, Conrad A

    2013-01-01

    A comparative phylogeographic study on two economically important African tick species, Amblyomma hebraeum and Hyalomma rufipes was performed to test the influence of host specificity and host movement on dispersion. Pairwise AMOVA analyses of 277 mtDNA COI sequences supported significant population differentiation among the majority of sampling sites. The geographic mitochondrial structure was not supported by nuclear ITS-2 sequencing, probably attributed to a recent divergence. The three-host generalist, A. hebraeum, showed less mtDNA geographic structure, and a lower level of genetic diversity, while the more host-specific H. rufipes displayed higher levels of population differentiation and two distinct mtDNA assemblages (one predominantly confined to South Africa/Namibia and the other to Mozambique and East Africa). A zone of overlap is present in southern Mozambique. A mechanistic climate model suggests that climate alone cannot be responsible for the disruption in female gene flow. Our findings furthermore suggest that female gene dispersal of ticks is more dependent on the presence of juvenile hosts in the environment than on the ability of adult hosts to disperse across the landscape. Documented interspecific competition between the juvenile stages of H. rufipes and H. truncatum is implicated as a contributing factor towards disrupting gene flow between the two southern African H. rufipes genetic assemblages.

  4. Glycerophosphodiester phosphodiesterase gene (glpQ) of Borrelia lonestari identified as a target for differentiating Borrelia species associated with hard ticks (Acari:Ixodidae).

    PubMed

    Bacon, Rendi Murphree; Pilgard, Mark A; Johnson, Barbara J B; Raffel, Sandra J; Schwan, Tom G

    2004-05-01

    A glpQ ortholog was identified in DNA from Borrelia lonestari-positive Amblyomma americanum, providing further evidence that B. lonestari is more closely related to the relapsing fever group spirochetes than to borreliae that cause Lyme disease. This finding provides a basis for developing diagnostic assays to differentiate species of borrelia transmitted by hard ticks.

  5. [IXODID TICKS (PARASITIFORMES: IXODIDAE) FROM SMALL MAMMALS IN DEFORESTED BOREAL HABITATS IN THE NORTHERN EUROPEAN RUSSIA].

    PubMed

    Bespyatova, L A; Bugmyrin, S V

    2015-01-01

    Changes in the population density of two hard tick species, Ixodes (Exopalpiger) trianguliceps Birula, 1895 and Ixodes persulcatus Schulze, 1930, were examined in 1998-2001, and in 2003-2004 near Gomselga Village (Kondopoga District, 62° 04' N, 33° 55' E) in central Karelia. Data on the abundance of ixodid ticks and the species composition of their hosts in 4 forest sites at different stages of post-felling regeneration (secondary succession), i. e. 7-14, 12-19, 25-32, and 80-87 after logging were obtained. I. persulcatus dominated, comprising 73 % of the total tick number in samples. Regenera- tion of the forest resulted in fluctuations of the population density of two examined tick species: I. (Exopalpiger) trianguliceps (larvae 2.8-5.3; nymphs 1.5-2.2; adults 0-0.09) and I. persulcatus (larvae 4.3-10.6; nymphs 0.6-4.2).

  6. Acoustical Scattering, Propagation, and Attenuation Caused by Two Abundant Pacific Schooling Species: Humboldt Squid and Hake

    DTIC Science & Technology

    2012-09-30

    Caused by Two Abundant Pacific Schooling Species: Humboldt Squid and Hake Kelly J. Benoit-Bird College of Oceanic and Atmospheric Sciences 104...Abundant Pacific Schooling Species: Humboldt Squid and Hake 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...with maximum lengths of up to 90 cm. A more recent immigrant to these waters, is the similarly sized and highly abundant jumbo or Humboldt squid

  7. Acaricidal activity of Palicourea marcgravii, a species from the Amazon forest, on cattle tick Rhipicephalus (Boophilus) microplus.

    PubMed

    Silva, Wilson Castro; Martins, João Ricardo de Souza; Cesio, Maria Veronica; Azevedo, João Lúcio; Heinzen, Horacio; de Barros, Neiva Monteiro

    2011-06-30

    Leaves of Palicourea marcgravii were extracted successively with hexane, ethyl acetate and ethanol in order to evaluate their acaricidal activity on larvae and adult stages of the cattle tick Rhipicephalus (Boophilus) microplus. The ethyl acetate extract showed the highest bioactivity of the tested extracts, which contained 0.12% monofluoroacetic acid. On engorged female, the ethyl acetate extract showed a lethal concentration 50% - LC(50)=30.08 mg ml(-1), inhibitory concentration 50% - IC(50)=5.79 mg ml(-1) and lethal time 50% - LT(50)=4.72 days; 100% reproduction was controlled at concentrations of 50 mg ml(-1) and on larvae the ethyl acetate extract showed a LC(50)=2.46 mg ml(-1). No alkaloids were detected in any of the extracts. This is the first report on the acaricidal activity of P. marcgravii extracts against R. microplus as well as the acaricidal properties of a plant species containing monofluoroacetic acid.

  8. Parasites of domestic and wild animals in South Africa. XLVIII. Ticks (Acari: Ixodidae) infesting domestic cats and wild felids in southern Africa.

    PubMed

    Horak, Ivan G; Heyne, Heloise; Donkin, Edward F

    2010-11-24

    Ticks collected from domestic cats (Felis catus), cheetahs (Acinonyx jubatus),caracals (Caracal caracal), African wild cats (Felis lybica), black-footed cats (Felis nigripes), a serval (Leptailurus serval), lions(Panthera leo), and leopards (Panthera pardus) were identified and counted. Thirteen species of ixodid ticks and one argasid tick were identified from domestic cats and 17 species of ixodid ticks from wild felids. The domestic cats and wild felids harboured 11 ixodid species in common. The adults of Haemaphysalis elliptica, the most abundant tick species infesting cats and wild felids, were most numerous on a domestic cat in late winter and in mid-summer, during 2 consecutive years. The recorded geographic distribution of the recently described Haemaphysalis colesbergensis, a parasite of cats and caracals, was extended by 2 new locality records in the Northern Cape Province, South Africa.

  9. Simultaneous detection of Anaplasma and Ehrlichia species in ruminants and detection of Ehrlichia ruminantium in Amblyomma variegatum ticks by reverse line blot hybridization.

    PubMed

    Bekker, Cornelis P J; de Vos, Sander; Taoufik, Amar; Sparagano, Olivier A E; Jongejan, Frans

    2002-10-22

    The detection of Anaplasma and Ehrlichia species is usually based on species-specific PCR assays, since no assay is yet available which can detect and identify these species simultaneously. To this end, we developed a reverse line blot (RLB) assay for simultaneous detection and identification of Anaplasma and Ehrlichia species in domestic ruminants and ticks. In a PCR the hypervariable V1 region of the 16S ribosomal RNA (rRNA) gene was amplified with a set of primers unique for members of the genera Anaplasma and Ehrlichia [Int. J. Syst. Evol. Microbiol. 51 (2001) 2145]. Amplified PCR products from blood of domestic ruminants or Amblyomma variegatum tick samples were hybridized onto a membrane to which eight species-specific oligonucleotide probes and one Ehrlichia and Anaplasma catch-all oligonucleotide probe were covalently linked. No DNA was amplified from uninfected blood, nor from other hemoparasites such as Theileria annulata, or Babesia bigemina. The species-specific probes did not cross-react with DNA amplified from other species. E. ruminantium, A. ovis and another Ehrlichia were identified by RLB in blood samples collected from small ruminants in Mozambique. Finally, A. variegatum ticks were tested after feeding on E. ruminantium infected sheep. E. ruminantium could be detected in adult ticks even if feeding of nymphs was carried out 3.5 years post-infection. In conclusion, the developed species-specific oligonucleotide probes used in an RLB assay can simultaneously detect and identify several Ehrlichia and Anaplasma species. However, as no quantitative data for the detection limit are available yet, only positive results are interpretable at this stage.

  10. Repellency of Deet and SS220 Applied to Skin Involves Olfactory Sensing by Two Species of Ticks

    DTIC Science & Technology

    2005-01-01

    3- methylbenzamide) is the active component of most tick repellents marketed for use on skin, although it can be used on clothing (Mount & Snoddy...phase were responsible for the observed avoid- ance responses by the ticks and that the modality for repellent activity in these compounds is...J.F., Solberg, V.B., Klun, J.A., Kramer, M., Debboun, M. (2004) Comparative activity of deet and AI3-37220 repellents against the ticks Ixodes

  11. Mosquitoes of Zika Forest, Uganda: species composition and relative abundance.

    PubMed

    Kaddumukasa, M A; Mutebi, J-P; Lutwama, J J; Masembe, C; Akol, A M

    2014-01-01

    Mosquito collections were conducted in Zika Forest near Entebbe, Uganda, from July 2009 through June 2010 using CO2-baited light traps, ovitraps, and human-baited catches. In total, 163,790 adult mosquitoes belonging to 12 genera and 58 species were captured. Of these, 22 species (38%) were captured in Zika Forest for the first time. All the new records found in the forest in this study had previously been captured in other regions of Uganda, implying that they are native to the country and do not represent new introductions. More than 20 species previously collected in Zika Forest were not detected in our collections, and this may suggest a change in the mosquito fauna during the past 40 yr or variation in species composition from year to year. Arboviruses of public health importance have previously been isolated from >50% of the 58 mosquito species captured in Zika Forest, which suggests ahigh potential for transmission and maintenance of a wide range of arboviruses in Zika Forest.

  12. Estimating abundances of interacting species using morphological traits, foraging guilds, and habitat

    USGS Publications Warehouse

    Dorazio, Robert M.; Connor, Edward F.

    2014-01-01

    We developed a statistical model to estimate the abundances of potentially interacting species encountered while conducting point-count surveys at a set of ecologically relevant locations - as in a metacommunity of species. In the model we assume that abundances of species with similar traits (e.g., body size) are potentially correlated and that these correlations, when present, may exist among all species or only among functionally related species (such as members of the same foraging guild). We also assume that species-specific abundances vary among locations owing to systematic and stochastic sources of heterogeneity. For example, if abundances differ among locations due to differences in habitat, then measures of habitat may be included in the model as covariates. Naturally, the quantitative effects of these covariates are assumed to differ among species. Our model also accounts for the effects of detectability on the observed counts of each species. This aspect of the model is especially important for rare or uncommon species that may be difficult to detect in community-level surveys. Estimating the detectability of each species requires sampling locations to be surveyed repeatedly using different observers or different visits of a single observer. As an illustration, we fitted models to species-specific counts of birds obtained while sampling an avian community during the breeding season. In the analysis we examined whether species abundances appeared to be correlated due to similarities in morphological measures (body mass, beak length, tarsus length, wing length, tail length) and whether these correlations existed among all species or only among species of the same foraging guild. We also used the model to estimate the effects of forested area on species abundances and the effects of sound power output (as measured by body size) on species detection probabilities.

  13. Estimating Abundances of Interacting Species Using Morphological Traits, Foraging Guilds, and Habitat

    PubMed Central

    Dorazio, Robert M.; Connor, Edward F.

    2014-01-01

    We developed a statistical model to estimate the abundances of potentially interacting species encountered while conducting point-count surveys at a set of ecologically relevant locations – as in a metacommunity of species. In the model we assume that abundances of species with similar traits (e.g., body size) are potentially correlated and that these correlations, when present, may exist among all species or only among functionally related species (such as members of the same foraging guild). We also assume that species-specific abundances vary among locations owing to systematic and stochastic sources of heterogeneity. For example, if abundances differ among locations due to differences in habitat, then measures of habitat may be included in the model as covariates. Naturally, the quantitative effects of these covariates are assumed to differ among species. Our model also accounts for the effects of detectability on the observed counts of each species. This aspect of the model is especially important for rare or uncommon species that may be difficult to detect in community-level surveys. Estimating the detectability of each species requires sampling locations to be surveyed repeatedly using different observers or different visits of a single observer. As an illustration, we fitted models to species-specific counts of birds obtained while sampling an avian community during the breeding season. In the analysis we examined whether species abundances appeared to be correlated due to similarities in morphological measures (body mass, beak length, tarsus length, wing length, tail length) and whether these correlations existed among all species or only among species of the same foraging guild. We also used the model to estimate the effects of forested area on species abundances and the effects of sound power output (as measured by body size) on species detection probabilities. PMID:24727898

  14. Species abundance in a forest community in South China: A case of poisson lognormal distribution

    USGS Publications Warehouse

    Yin, Z.-Y.; Ren, H.; Zhang, Q.-M.; Peng, S.-L.; Guo, Q.-F.; Zhou, G.-Y.

    2005-01-01

    Case studies on Poisson lognormal distribution of species abundance have been rare, especially in forest communities. We propose a numerical method to fit the Poisson lognormal to the species abundance data at an evergreen mixed forest in the Dinghushan Biosphere Reserve, South China. Plants in the tree, shrub and herb layers in 25 quadrats of 20 m??20 m, 5 m??5 m, and 1 m??1 m were surveyed. Results indicated that: (i) for each layer, the observed species abundance with a similarly small median, mode, and a variance larger than the mean was reverse J-shaped and followed well the zero-truncated Poisson lognormal; (ii) the coefficient of variation, skewness and kurtosis of abundance, and two Poisson lognormal parameters (?? and ??) for shrub layer were closer to those for the herb layer than those for the tree layer; and (iii) from the tree to the shrub to the herb layer, the ?? and the coefficient of variation decreased, whereas diversity increased. We suggest that: (i) the species abundance distributions in the three layers reflects the overall community characteristics; (ii) the Poisson lognormal can describe the species abundance distribution in diverse communities with a few abundant species but many rare species; and (iii) 1/?? should be an alternative measure of diversity.

  15. Relationships between species richness, evenness, and abundance in a southwestern savanna.

    PubMed

    Bock, Carl E; Jones, Zach F; Bock, Jane H

    2007-05-01

    Species richness and evenness are components of biological diversity that may or may not be correlated with one another and with patterns of species abundance. We compared these attributes among flowering plants, grasshoppers, butterflies, lizards, summer birds, winter birds, and rodents across 48 plots in the grasslands and mesquite-oak savannas of southeastern Arizona. Species richness and evenness were uncorrelated or weakly negatively correlated for each taxonomic group, supporting the conclusion that richness alone is an incomplete measure of diversity. In each case, richness was positively correlated with one or more measures of abundance. By contrast, evenness usually was negatively correlated with the abundance variables, reflecting the fact that plots with high evenness generally were those where all species present were about equally uncommon. Therefore richness, but not evenness, usually was a positive predictor of places of conservation value, if these are defined as places where species of interest are especially abundant. Species diversity was more positively correlated with evenness than with richness among grasshoppers and flowering plants, in contrast to the other taxonomic groups, and the positive correlations between richness and abundance were comparatively weak for grasshoppers and plants as well. Both of these differences can be attributed to the fact that assemblages of plants and grasshoppers were numerically dominated by small subsets of common species (grasses and certain spur-throated grasshoppers) whose abundances differed greatly among plots in ways unrelated to species richness of the groups as a whole.

  16. Urbanization level and woodland size are major drivers of woodpecker species richness and abundance.

    PubMed

    Myczko, Lukasz; Rosin, Zuzanna M; Skórka, Piotr; Tryjanowski, Piotr

    2014-01-01

    Urbanization is a process globally responsible for loss of biodiversity and for biological homogenization. Urbanization may have a direct negative impact on species behaviour and indirect effects on species populations through alterations of their habitats, for example patch size and habitat quality. Woodpeckers are species potentially susceptible to urbanization. These birds are mostly forest specialists and the development of urban areas in former forests may be an important factor influencing their richness and abundance, but documented examples are rare. In this study we investigated how woodpeckers responded to changes in forest habitats as a consequence of urbanization, namely size and isolation of habitat patches, and other within-patch characteristics. We selected 42 woodland patches in a gradient from a semi-natural rural landscape to the city centre of Poznań (Western Poland) in spring 2010. Both species richness and abundance of woodpeckers correlated positively to woodland patch area and negatively to increasing urbanization. Abundance of woodpeckers was also positively correlated with shrub cover and percentage of deciduous tree species. Furthermore, species richness and abundance of woodpeckers were highest at moderate values of canopy openness. Ordination analyses confirmed that urbanization level and woodland patch area were variables contributing most to species abundance in the woodpecker community. Similar results were obtained in presence-absence models for particular species. Thus, to sustain woodpecker species within cities it is important to keep woodland patches large, multi-layered and rich in deciduous tree species.

  17. Urbanization Level and Woodland Size Are Major Drivers of Woodpecker Species Richness and Abundance

    PubMed Central

    Myczko, Łukasz; Rosin, Zuzanna M.; Skórka, Piotr; Tryjanowski, Piotr

    2014-01-01

    Urbanization is a process globally responsible for loss of biodiversity and for biological homogenization. Urbanization may have a direct negative impact on species behaviour and indirect effects on species populations through alterations of their habitats, for example patch size and habitat quality. Woodpeckers are species potentially susceptible to urbanization. These birds are mostly forest specialists and the development of urban areas in former forests may be an important factor influencing their richness and abundance, but documented examples are rare. In this study we investigated how woodpeckers responded to changes in forest habitats as a consequence of urbanization, namely size and isolation of habitat patches, and other within-patch characteristics. We selected 42 woodland patches in a gradient from a semi-natural rural landscape to the city centre of Poznań (Western Poland) in spring 2010. Both species richness and abundance of woodpeckers correlated positively to woodland patch area and negatively to increasing urbanization. Abundance of woodpeckers was also positively correlated with shrub cover and percentage of deciduous tree species. Furthermore, species richness and abundance of woodpeckers were highest at moderate values of canopy openness. Ordination analyses confirmed that urbanization level and woodland patch area were variables contributing most to species abundance in the woodpecker community. Similar results were obtained in presence-absence models for particular species. Thus, to sustain woodpecker species within cities it is important to keep woodland patches large, multi-layered and rich in deciduous tree species. PMID:24740155

  18. Associations of forest cover, fragment area, and connectivity with neotropical understory bird species richness and abundance.

    PubMed

    Martensen, Alexandre Camargo; Ribeiro, Milton Cezar; Banks-Leite, Cristina; Prado, Paulo Inácio; Metzger, Jean Paul

    2012-12-01

    Theoretical and empirical studies demonstrate that the total amount of forest and the size and connectivity of fragments have nonlinear effects on species survival. We tested how habitat amount and configuration affect understory bird species richness and abundance. We used mist nets (almost 34,000 net hours) to sample birds in 53 Atlantic Forest fragments in southeastern Brazil. Fragments were distributed among 3 10,800-ha landscapes. The remaining forest in these landscapes was below (10% forest cover), similar to (30%), and above (50%) the theoretical fragmentation threshold (approximately 30%) below which the effects of fragmentation should be intensified. Species-richness estimates were significantly higher (F= 3715, p = 0.00) where 50% of the forest remained, which suggests a species occurrence threshold of 30-50% forest, which is higher than usually occurs (<30%). Relations between forest cover and species richness differed depending on species sensitivity to forest conversion and fragmentation. For less sensitive species, species richness decreased as forest cover increased, whereas for highly sensitive species the opposite occurred. For sensitive species, species richness and the amount of forest cover were positively related, particularly when forest cover was 30-50%. Fragment size and connectivity were related to species richness and abundance in all landscapes, not just below the 30% threshold. Where 10% of the forest remained, fragment size was more related to species richness and abundance than connectivity. However, the relation between connectivity and species richness and abundance was stronger where 30% of the landscape was forested. Where 50% of the landscape was forested, fragment size and connectivity were both related to species richness and abundance. Our results demonstrated a rapid loss of species at relatively high levels of forest cover (30-50%). Highly sensitive species were 3-4 times more common above the 30-50% threshold than below it

  19. Susceptibility of Four Tick Species Amblyomma americanum, Dermacentor variabilis, Ixodes scapularis, and Rhipicephalus sanguineus (Acari: Ixodidae) to Nootkatone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The essential oil nootkatone has shown acaricidal activity on ticks. The toxicity of nootkatone was determined in laboratory assays using a vial coating technique against unfed nymphs of four Ixodid ticks: Amblyomma americanum L., Dermacentor variabilis (Say), Ixodes scapularis Say, and Rhipicepha...

  20. Differential tick burdens may explain differential Borrelia afzelii and Borrelia garinii infection rates among four, wild, rodent species in Hokkaido, Japan.

    PubMed

    Taylor, Kyle R; Takano, Ai; Konnai, Satoru; Shimozuru, Michito; Kawabata, Hiroki; Tsubota, Toshio

    2013-01-01

    The ecologies of Lyme disease Borrelia spp. are very specific to location, as they are dependent upon the spirochete species and genotypes, the vectors and the host vertebrates present. In Hokkaido, Japan, where two human pathogenic, Lyme disease Borrelia spp. are present, and human cases are reported annually, the ecologies have been poorly studied. Our goal was to determine whether variation in borrelial infection rates among rodent species sharing an environment, is due to immunological or ecological differences. To this end, we examined the relationships between tick burden and borrelial infection, by including examination of agreement between nested PCR, as a test for infection, and serology, as a test for exposure. We collected 868 rodents, comprised of four species commonly found in Hokkaido, and tested for infection rates with Borrelia spp. using PCR for the borrelial flaB gene, seroprevalence of Borrelia afzelii and Borrelia garinii using ELISA, and attachment of ticks by direct counts. We noted a correlation between differential nymph and larval burdens and the borrelial infection rates found among the four rodent species. Furthermore, there was significant correlation between infection and seroprevalence of B. afzelii and B. garinii (P<0.01), between infection and Ixodes persulcatus nymph burden (P<0.01), and between seroprevalence and I. persulcatus nymph burden (P<0.01). The close agreement among rodent species seroprevalences with infection rates and tick burdens suggest the differences in infection rates of Borrelia spp. may largely be a direct consequence of differential exposure to vectors.

  1. Macroalgal mats and species abundance: a field experiment

    NASA Astrophysics Data System (ADS)

    Hull, S. C.

    1987-11-01

    A field experiment was carried out whereby the density of macroalgae ( Enteromorpha spp.) was manipulated and the resultant changes in sediment infaunal density were monitored. Four densities of Enteromorpha spp. were used: 0,0·3, 1, and 3 kg FW m -2, corresponding to control, low-, medium-, and high-density plots. The experiment ran from May to October 1985 and was sampled on three occasions. By July, the density of Corophium volutator was reduced at all weed levels when compared to control plots, whereas densities of Hydrobia ulvae, Macoma balthica, Nereis diversicolor, and Capitella capitata, all increased. Samples taken in October when the weed mats were buried in the sediment showed fewer differences than in July. Macoma, Nereis, and Capitella were still significantly more abundant at medium and high weed densities. Corophium showed no significant treatment effect. There was, however, a highly significant difference in population size structure for Corophium. Measurements of sediment redox potential and silt content under medium- and high-density plots revealed rapid anoxia with a significant increase in siltation.

  2. Topographic variables improve climate models of forage species abundance in the northeastern United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Species distribution modeling has most commonly been applied to presence-only data and to woody species, but detailed predicted abundance maps for forage species would be of great value for agricultural management and land use planning. We used field data from 107 farms across the northeastern Unite...

  3. Ticks on dogs and cats: a pet owner-based survey in a rural town in northeastern Switzerland.

    PubMed

    Eichenberger, Ramon Marc; Deplazes, Peter; Mathis, Alexander

    2015-04-01

    Changes in the endemic foci of tick populations and invasions of tick species to new areas have become evident in Europe, leading to changes in the epidemiology of tick-transmitted diseases. However, data about tick infestations of pet animals are limited. Following the recent identification of a new focus of canine babesiosis in northeastern Switzerland, we investigated the occurrence of tick vectors in this region by using a pet owner-based sampling strategy. All dog owners in a rural town were sent postal requests to send ticks from their dogs and cats over two consecutive years, beginning in April 2012. In total 3003 ticks were submitted for identification from 249 dogs (approximately 20% of the resident dog population) and from 117 cats. Ixodes ricinus was the most abundant species identified in 96.8% (n=2124) and 74.3% (n=601) of the individual samples submitted from dogs and cats, respectively. Two other tick species, I. hexagonus and Dermacentor reticulatus, were recorded on both host species, with host infestation prevalences below 2%. On cats (but not on dogs), as many as 24.0% (n=194) of the specimens were identified as a fourth tick species, I. trianguliceps. Overall, 93.5% of the ticks were adults (93.8% and 93.0% in dogs and cats), 4.4% nymphs (5.7% in dogs and 1% in cats) and 2% larvae (0.5% and 6.0% in dogs and cats), respectively. The highest infestation intensity was 49 I. ricinus ticks from an individual dog. However, 55.6% of the submissions from dogs and 24.8% from cats contained only one tick. This survey demonstrated that pet owners can contribute to a cost-effective tick surveillance and identified a new tick focus of D. reticulatus. The finding of I. trianguliceps exclusively on cats might be related to behavioural traits of the cats or to a more readily detection of these very small ticks during petting by their owners.

  4. Species-abundance--seed-size patterns within a plant community affected by grazing disturbance.

    PubMed

    Wu, Gao-lin; Shang, Zhan-huan; Zhu, Yuan-jun; Ding, Lu-ming; Wang, Dong

    2015-04-01

    Seed size has been advanced as a key factor that influences the dynamics of plant communities, but there are few empirical or theoretical predictions of how community dynamics progress based on seed size patterns. Information on the abundance of adults, seedlings, soil seed banks, seed rains, and the seed mass of 96 species was collected in alpine meadows of the Qinghai-Tibetan Plateau (China), which had different levels of grazing disturbance. The relationships between seed-mass-abundance patterns for adults, seedlings, the soil seed bank, and seed rain in the plant community were evaluated using regression models. Results showed that grazing levels affected the relationship between seed size and abundance properties of adult species, seedlings, and the soil seed bank, suggesting that there is a shift in seed-size--species-abundance relationships as a response to the grazing gradient. Grazing had no effect on the pattern of seed-size-seed-rain-abundance at four grazing levels. Grazing also had little effect on the pattern of seed-size--species-abundance and pattern of seed-size--soil-seed-bank-abundance in meadows with no grazing, light grazing, and moderate grazing), but there was a significant negative effect in meadows with heavy grazing. Grazing had little effect on the pattern of seed-size--seedling-abundance with no grazing, but had significant negative effects with light, moderate, and heavy grazing, and the |r| values increased with grazing levels. This indicated that increasing grazing pressure enhanced the advantage of smaller-seeded species in terms of the abundances of adult species, seedlings, and soil seed banks, whereas only the light grazing level promoted the seed rain abundance of larger-seeded species in the plant communities. This study suggests that grazing disturbances are favorable for increasing the species abundance for smaller-seeded species but not for the larger-seeded species in an alpine meadow community. Hence, there is a clear

  5. Accounting for dispersal and biotic interactions to disentangle the drivers of species distributions and their abundances

    PubMed Central

    Boulangeat, Isabelle; Gravel, Dominique; Thuiller, Wilfried

    2014-01-01

    Although abiotic factors, together with dispersal and biotic interactions, are often suggested to explain the distribution of species and their abundances, species distribution models usually focus on abiotic factors only. We propose an integrative framework linking ecological theory, empirical data and statistical models to understand the distribution of species and their abundances together with the underlying community assembly dynamics. We illustrate our approach with 21 plant species in the French Alps. We show that a spatially nested modelling framework significantly improves the model’s performance and that the spatial variations of species presence–absence and abundances are predominantly explained by different factors. We also show that incorporating abiotic, dispersal and biotic factors into the same model bring new insights to our understanding of community assembly. This approach, at the crossroads between community ecology and biogeography, is a promising avenue for a better understanding of species co-existence and biodiversity distribution. PMID:22462813

  6. A common scaling rule for abundance, energetics, and production of parasitic and free-living species

    USGS Publications Warehouse

    Hechinger, Ryan F.; Lafferty, Kevin D.; Dobson, Andy P.; Brown, James H.; Kuris, Armand M.

    2011-01-01

    The metabolic theory of ecology uses the scaling of metabolism with body size and temperature to explain the causes and consequences of species abundance. However, the theory and its empirical tests have never simultaneously examined parasites alongside free-living species. This is unfortunate because parasites represent at least half of species diversity. We show that metabolic scaling theory could not account for the abundance of parasitic or free-living species in three estuarine food webs until accounting for trophic dynamics. Analyses then revealed that the abundance of all species uniformly scaled with body mass to the - 3/4 power. This result indicates "production equivalence," where biomass production within trophic levels is invariant of body size across all species and functional groups: invertebrate or vertebrate, ectothermic or endothermic, and free-living or parasitic.

  7. A common scaling rule for abundance, energetics, and production of parasitic and free-living species.

    PubMed

    Hechinger, Ryan F; Lafferty, Kevin D; Dobson, Andy P; Brown, James H; Kuris, Armand M

    2011-07-22

    The metabolic theory of ecology uses the scaling of metabolism with body size and temperature to explain the causes and consequences of species abundance. However, the theory and its empirical tests have never simultaneously examined parasites alongside free-living species. This is unfortunate because parasites represent at least half of species diversity. We show that metabolic scaling theory could not account for the abundance of parasitic or free-living species in three estuarine food webs until accounting for trophic dynamics. Analyses then revealed that the abundance of all species uniformly scaled with body mass to the -¾ power. This result indicates "production equivalence," where biomass production within trophic levels is invariant of body size across all species and functional groups: invertebrate or vertebrate, ectothermic or endothermic, and free-living or parasitic.

  8. The effect of soil-borne pathogens depends on the abundance of host tree species

    PubMed Central

    Liu, Yu; Fang, Suqin; Chesson, Peter; He, Fangliang

    2015-01-01

    The overarching issue for understanding biodiversity maintenance is how fitness advantages accrue to a species as it becomes rare, as this is the defining feature of stable coexistence mechanisms. Without these fitness advantages, average fitness differences between species will lead to exclusion. However, empirical evidence is lacking, especially for forests, due to the difficulty of manipulating density on a large-enough scale. Here we took advantage of naturally occurring contrasts in abundance between sites of a subtropical tree species, Ormosia glaberrima, to demonstrate how low-density fitness advantages accrue by the Janzen–Connell mechanism. The results showed that soil pathogens suppressed seedling recruitment of O. glaberrima when it is abundant but had little effect on the seedlings when it is at low density due to the lack of pathogens. The difference in seedling survival between abundant and low-density sites demonstrates strong dependence of pathogenic effect on the abundance of host species. PMID:26632594

  9. Molecular detection of murine herpesvirus 68 in ticks feeding on free-living reptiles.

    PubMed

    Ficová, Martina; Betáková, Tatiana; Pančík, Peter; Václav, Radovan; Prokop, Pavol; Halásová, Zuzana; Kúdelová, Marcela

    2011-11-01

    The MHV-68 (designed as Murid herpesvirus 4 (MuHV 4) strain 68) isolated from two rodents, Myodes glareolus and Apodemus flavicollis, is considered as a natural pathogen of free-living murid rodents. Recently, the detection of MHV antibodies in the blood of animals living in the same biotope as MHV-infected mice has suggested that ticks may have a role in the transmission of this pathogen. Ixodes ricinus is one the most abundant tick species in Europe known to transmit multiple pathogens causing human and animal diseases. In this study, nymphs and larvae feeding on 116 individuals of a temperate lizard species-the green lizard Lacerta viridis captured in the Slovak Karst National Park, were examined for MHV-68. The specific sequence of virion glycoprotein 150 was amplified in DNA individually isolated from I. ricinus ticks using single-copy sensitive nested polymerase chain reaction. MHV-68 was detected in ten of 649 nymphs and in five of 150 larvae, respectively. We found that 9.6% of green lizards fed at least one MHV-68-infected immature tick. Occurrence of MHV-68 within all ticks tested was 1.8%. This study is first to show that immature I. ricinus ticks feeding on free-living lizards in a Central European region could be infected with gammaherpesvirus (MHV-68), naturally infecting free-living murid rodents. Our results provide evidence supporting the hypothesis that ticks may play a mediating role in circulation of MHV-68 in nature.

  10. Detection of tick-borne encephalitis virus in I. ricinus ticks collected from autumn migratory birds in Latvia.

    PubMed

    Kazarina, Alisa; Japiņa, Kristīne; Keišs, Oskars; Salmane, Ineta; Bandere, Dace; Capligina, Valentina; Ranka, Renāte

    2015-03-01

    Birds have a potential of spreading ticks via bird migration routes. In this study, we screened 170 ticks removed during autumn 2010 from 55 birds belonging to 10 species for the presence of tick-borne encephalitis virus (TBEV). In total, TBEV RNA was detected in 14% of I. ricinus tick samples obtained from different birds species. The results of this study indicate the possible role of migrating birds in the dispersal of TBEV-infected ticks along the southward migration route.

  11. Changes in the Relative Abundance of Two Saccharomyces Species from Oak Forests to Wine Fermentations

    PubMed Central

    Dashko, Sofia; Liu, Ping; Volk, Helena; Butinar, Lorena; Piškur, Jure; Fay, Justin C.

    2016-01-01

    Saccharomyces cerevisiae and its sibling species Saccharomyces paradoxus are known to inhabit temperate arboreal habitats across the globe. Despite their sympatric distribution in the wild, S. cerevisiae is predominantly associated with human fermentations. The apparent ecological differentiation of these species is particularly striking in Europe where S. paradoxus is abundant in forests and S. cerevisiae is abundant in vineyards. However, ecological differences may be confounded with geographic differences in species abundance. To compare the distribution and abundance of these two species we isolated Saccharomyces strains from over 1200 samples taken from vineyard and forest habitats in Slovenia. We isolated numerous strains of S. cerevisiae and S. paradoxus, as well as a small number of Saccharomyces kudriavzevii strains, from both vineyard and forest environments. We find S. cerevisiae less abundant than S. paradoxus on oak trees both within and outside the vineyard, but more abundant on grapevines and associated substrates. Analysis of the uncultured microbiome shows, that both S. cerevisiae and S. paradoxus are rare species in soil and bark samples, but can be much more common in grape must. In contrast to S. paradoxus, European strains of S. cerevisiae have acquired multiple traits thought to be important for life in the vineyard and dominance of wine fermentations. We conclude, that S. cerevisiae and S. paradoxus currently share both vineyard and non-vineyard habitats in Slovenia and we discuss factors relevant to their global distribution and relative abundance. PMID:26941733

  12. Strategies for new and improved vaccines against ticks and tick-borne diseases.

    PubMed

    de la Fuente, J; Kopáček, P; Lew-Tabor, A; Maritz-Olivier, C

    2016-12-01

    Ticks infest a variety of animal species and transmit pathogens causing disease in both humans and animals worldwide. Tick-host-pathogen interactions have evolved through dynamic processes that accommodated the genetic traits of the hosts, pathogens transmitted and the vector tick species that mediate their development and survival. New approaches for tick control are dependent on defining molecular interactions between hosts, ticks and pathogens to allow for discovery of key molecules that could be tested in vaccines or new generation therapeutics for intervention of tick-pathogen cycles. Currently, tick vaccines constitute an effective and environmentally sound approach for the control of ticks and the transmission of the associated tick-borne diseases. New candidate protective antigens will most likely be identified by focusing on proteins with relevant biological function in the feeding, reproduction, development, immune response, subversion of host immunity of the tick vector and/or molecules vital for pathogen infection and transmission. This review addresses different approaches and strategies used for the discovery of protective antigens, including focusing on relevant tick biological functions and proteins, reverse genetics, vaccinomics and tick protein evolution and interactomics. New and improved tick vaccines will most likely contain multiple antigens to control tick infestations and pathogen infection and transmission.

  13. Acoustical Scattering, Propagation, and Attenuation Caused by Two Abundant Pacific Schooling Species: Humboldt Squid and Hake

    DTIC Science & Technology

    2011-09-30

    Caused by Two Abundant Pacific Schooling Species: Humboldt Squid and Hake Kelly J. Benoit-Bird College of Oceanic and Atmospheric Sciences 104...Attenuation Caused by Two Abundant Pacific Schooling Species: Humboldt Squid and Hake 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...have successfully recruited graduate students that will conduct thesis research as part of this project. RESULTS Both hake and Humboldt squid

  14. Ticks infesting humans in Northern Misiones, Argentina.

    PubMed

    Lamattina, Daniela; Nava, Santiago

    2016-01-01

    This work presents records of ticks infesting humans in northern Misiones Province, Argentina. Also, notes on potential transmission of tick-borne pathogens are included. A total of 282 ticks attached to researchers were collected and identified by their morphological characters. Eight tick species were found: Amblyomma brasiliense, Amblyomma coelebs, Amblyomma dubitatum, Amblyomma incisum, Amblyomma ovale, Haemaphysalis juxtakochi, Rhipicephalus sanguineus and Rhipicephalus microplus. Some of these species as A. dubitatum, A. ovale and R. sanguineus have been found infected with spotted fever group rickettsiae pathogenic to humans in Brazil and Argentina. The potential role as vectors of humans pathogens of the ticks found attached to humans in this study is discussed.

  15. Distribution pattern and number of ticks on lizards.

    PubMed

    Dudek, Krzysztof; Skórka, Piotr; Sajkowska, Zofia Anna; Ekner-Grzyb, Anna; Dudek, Monika; Tryjanowski, Piotr

    2016-02-01

    The success of ectoparasites depends primarily on the site of attachment and body condition of their hosts. Ticks usually tend to aggregate on vertebrate hosts in specific areas, but the distribution pattern may depend on host body size and condition, sex, life stage or skin morphology. Here, we studied the distribution of ticks on lizards and tested the following hypothesis: occurrence or high abundance of ticks is confined with body parts with smaller scales and larger interscalar length because such sites should provide ticks with superior attachment conditions. This study was performed in field conditions in central Poland in 2008-2011. In total, 500 lizards (Lacerta agilis) were caught and 839 ticks (Ixodes ricinus, larvae and nymphs) were collected from them. Using generalised linear mixed models, we found that the ticks were most abundant on forelimbs and their axillae, with 90% of ticks attached there. This part of the lizard body and the region behind the hindlimb were covered by the smallest scales with relatively wide gaps between them. This does not fully support our hypothesis that ticks prefer locations with easy access to skin between scales, because it does not explain why so few ticks were in the hindlimb area. We found that the abundance of ticks was positively correlated with lizard body size index (snout-vent length). Tick abundance was also higher in male and mature lizards than in female and young individuals. Autotomy had no effect on tick abundance. We found no correlation between tick size and lizard morphology, sex, autotomy and body size index. The probability of occurrence of dead ticks was positively linked with the total number of ticks on the lizard but there was no relationship between dead tick presence and lizard size, sex or age. Thus lizard body size and sex are the major factors affecting the abundance of ticks, and these parasites are distributed nearly exclusively on the host's forelimbs and their axillae.

  16. Assessing the sensitivity of avian species abundance to land cover and climate

    USGS Publications Warehouse

    LeBrun, Jaymi J.; Thogmartin, Wayne E.; Thompson, Frank R.; Dijak, William D.; Millspaugh, Joshua J.

    2016-01-01

    Climate projections for the Midwestern United States predict southerly climates to shift northward. These shifts in climate could alter distributions of species across North America through changes in climate (i.e., temperature and precipitation), or through climate-induced changes on land cover. Our objective was to determine the relative impacts of land cover and climate on the abundance of five bird species in the Central United States that have habitat requirements ranging from grassland and shrubland to forest. We substituted space for time to examine potential impacts of a changing climate by assessing climate and land cover relationships over a broad latitudinal gradient. We found positive and negative relationships of climate and land cover factors with avian abundances. Habitat variables drove patterns of abundance in migratory and resident species, although climate was also influential in predicting abundance for some species occupying more open habitat (i.e., prairie warbler, blue-winged warbler, and northern bobwhite). Abundance of northern bobwhite increased with winter temperature and was the species exhibiting the most significant effect of climate. Models for birds primarily occupying early successional habitats performed better with a combination of habitat and climate variables whereas models of species found in contiguous forest performed best with land cover alone. These varied species-specific responses present unique challenges to land managers trying to balance species conservation over a variety of land covers. Management activities focused on increasing forest cover may play a role in mitigating effects of future climate by providing habitat refugia to species vulnerable to projected changes. Conservation efforts would be best served focusing on areas with high species abundances and an array of habitats. Future work managing forests for resilience and resistance to climate change could benefit species already susceptible to climate impacts.

  17. The Evolving Medical and Veterinary Importance of the Gulf Coast tick (Acari: Ixodidae).

    PubMed

    Paddock, Christopher D; Goddard, Jerome

    2015-03-01

    Amblyomma maculatum Koch (the Gulf Coast tick) is a three-host, ixodid tick that is distributed throughout much of the southeastern and south-central United States, as well as several countries throughout Central and South America. A considerable amount of scientific literature followed the original description of A. maculatum in 1844; nonetheless, the Gulf Coast tick was not recognized as a vector of any known pathogen of animals or humans for >150 years. It is now identified as the principal vector of Hepatozoon americanum, the agent responsible for American canine hepatozoonosis, and Rickettsia parkeri, the cause of an emerging, eschar-associated spotted fever group rickettsiosis identified throughout much of the Western Hemisphere. Coincident with these discoveries has been recognition that the geographical distribution of A. maculatum in the United States is far more extensive than described 70 yr ago, supporting the idea that range and abundance of certain tick species, particularly those with diverse host preferences, are not fixed in time or space, and may change over relatively short intervals. Renewed interest in the Gulf Coast tick reinforces the notion that the perceived importance of a particular tick species to human or animal health can be relatively fluid, and may shift dramatically with changes in the distribution and abundance of the arthropod, its vertebrate hosts, or the microbial agents that transit among these organisms.

  18. FleaTickRisk: a meteorological model developed to monitor and predict the activity and density of three tick species and the cat flea in Europe.

    PubMed

    Beugnet, Frédéric; Chalvet-Monfray, Karine; Loukos, Harilaos

    2009-11-01

    Mathematical modelling is quite a recent tool in epidemiology. Geographical information system (GIS) combined with remote sensing (data collection and analysis) provide valuable models, but the integration of climatologic models in parasitology and epidemiology is less common. The aim of our model, called "FleaTickRisk", was to use meteorological data and forecasts to monitor the activity and density of some arthropods. Our parasitological model uses the Weather Research and Forecasting (WRF) meteorological model integrating biological parameters. The WRF model provides a temperature and humidity picture four times a day (at 6:00, 12:00, 18:00 and 24:00 hours). Its geographical resolution is 27 x 27 km over Europe (area between longitudes 10.5 degrees W and 30 degrees E and latitudes 37.75 degrees N and 62 degrees N). The model also provides weekly forecasts. Past data were compared and revalidated using current meteorological data generated by ground stations and weather satellites. The WRF model also includes geographical information stemming from United States Geophysical Survey biotope maps with a 30'' spatial resolution (approximately 900 x 900 m). WRF takes into account specific climatic conditions due to valleys, altitudes, lakes and wind specificities. The biological parameters of Ixodes ricinus, Dermacentor reticulatus, Rhipicephalus sanguineus and Ctenocephalides felis felis were transformed into a matrix of activity. This activity matrix is expressed as a percentage, ranging from 0 to 100, for each interval of temperature x humidity. The activity of these arthropods is defined by their ability to infest hosts, take blood meals and reproduce. For each arthropod, the matrix was calculated using existing data collected under optimal temperature and humidity conditions, as well as the timing of the life cycle. The mathematical model integrating both the WRF model (meteorological data + geographical data) and the biological matrix provides two indexes: an

  19. Species diversity and seasonal abundance of Culicoides biting midges in northwestern Argentina.

    PubMed

    Aybar, C A Veggiani; Juri, M J Dantur; De Grosso, M S Lizarralde; Spinelli, G R

    2010-03-01

    The species diversity and seasonal abundance of biting midges of the genus Culicoides (Diptera: Ceratopogonidae) were studied in northwestern Argentina during the period 2003-2005. A total of 5437 Culicoides specimens were collected using CDC light traps in three areas of the mountainous rainforest area. The most common species were Culicoides paraensis (Goeldi) and C. insignis Lutz, Culicoides lahillei (Iches), C. venezuelensis Ortiz & Mirsa, C. debilipalpis Lutz and C. crescentis Wirth & Blanton were also collected. Culicoides paraensis was abundant during the summer, and C. insignis and C. lahillei during late summer and early fall. Accumulated rainfall was the climatic variable most related to fluctuation in abundance of C. paraensis.

  20. Remembrance of things past: modelling the relationship between species' abundances in living communities and death assemblages.

    PubMed

    Olszewski, Thomas D

    2012-02-23

    Accumulations of dead skeletal material are a valuable archive of past ecological conditions. However, such assemblages are not equivalent to living communities because they mix the remains of multiple generations and are altered by post-mortem processes. The abundance of a species in a death assemblage can be quantitatively modelled by successively integrating the product of an influx time series and a post-mortem loss function (a decay function with a constant half-life). In such a model, temporal mixing increases expected absolute dead abundance relative to average influx as a linear function of half-life and increases variation in absolute dead abundance values as a square-root function of half-life. Because typical abundance distributions of ecological communities are logarithmically distributed, species' differences in preservational half-life would have to be very large to substantially alter species' abundance ranks (i.e. make rare species common or vice-versa). In addition, expected dead abundances increase at a faster rate than their range of variation with increased time averaging, predicting greater consistency in the relative abundance structure of death assemblages than their parent living community.

  1. Molecular Ecological Insights into Neotropical Bird-Tick Interactions.

    PubMed

    Miller, Matthew J; Esser, Helen J; Loaiza, Jose R; Herre, Edward Allen; Aguilar, Celestino; Quintero, Diomedes; Alvarez, Eric; Bermingham, Eldredge

    2016-01-01

    In the tropics, ticks parasitize many classes of vertebrate hosts. However, because many tropical tick species are only identifiable in the adult stage, and these adults usually parasitize mammals, most attention on the ecology of tick-host interactions has focused on mammalian hosts. In contrast, immature Neotropical ticks are often found on wild birds, yet difficulties in identifying immatures hinder studies of birds' role in tropical tick ecology and tick-borne disease transmission. In Panama, we found immature ticks on 227 out of 3,498 individually-sampled birds representing 93 host species (24% of the bird species sampled, and 13% of the Panamanian land bird fauna). Tick parasitism rates did not vary with rainfall or temperature, but did vary significantly with several host ecological traits. Likewise, Neotropical-Nearctic migratory birds were significantly less likely to be infested than resident species. Using a molecular library developed from morphologically-identified adult ticks specifically for this study, we identified eleven tick species parasitizing birds, indicating that a substantial portion of the Panamanian avian species pool is parasitized by a diversity of tick species. Tick species that most commonly parasitized birds had the widest diversity of avian hosts, suggesting that immature tick species are opportunistic bird parasites. Although certain avian ecological traits are positively associated with parasitism, we found no evidence that individual tick species show specificity to particular avian host ecological traits. Finally, our data suggest that the four principal vectors of Rocky Mountain Spotted Fever in the Neotropics rarely, if ever, parasitize Panamanian birds. However, other tick species that harbor newly-discovered rickettsial parasites of unknown pathogenicity are frequently found on these birds. Given our discovery of broad interaction between Panamanian tick and avian biodiversity, future work on tick ecology and the dynamics of

  2. Molecular Ecological Insights into Neotropical Bird–Tick Interactions

    PubMed Central

    Esser, Helen J.; Loaiza, Jose R.; Herre, Edward Allen; Aguilar, Celestino; Quintero, Diomedes; Alvarez, Eric; Bermingham, Eldredge

    2016-01-01

    In the tropics, ticks parasitize many classes of vertebrate hosts. However, because many tropical tick species are only identifiable in the adult stage, and these adults usually parasitize mammals, most attention on the ecology of tick-host interactions has focused on mammalian hosts. In contrast, immature Neotropical ticks are often found on wild birds, yet difficulties in identifying immatures hinder studies of birds’ role in tropical tick ecology and tick-borne disease transmission. In Panama, we found immature ticks on 227 out of 3,498 individually–sampled birds representing 93 host species (24% of the bird species sampled, and 13% of the Panamanian land bird fauna). Tick parasitism rates did not vary with rainfall or temperature, but did vary significantly with several host ecological traits. Likewise, Neotropical–Nearctic migratory birds were significantly less likely to be infested than resident species. Using a molecular library developed from morphologically–identified adult ticks specifically for this study, we identified eleven tick species parasitizing birds, indicating that a substantial portion of the Panamanian avian species pool is parasitized by a diversity of tick species. Tick species that most commonly parasitized birds had the widest diversity of avian hosts, suggesting that immature tick species are opportunistic bird parasites. Although certain avian ecological traits are positively associated with parasitism, we found no evidence that individual tick species show specificity to particular avian host ecological traits. Finally, our data suggest that the four principal vectors of Rocky Mountain Spotted Fever in the Neotropics rarely, if ever, parasitize Panamanian birds. However, other tick species that harbor newly–discovered rickettsial parasites of unknown pathogenicity are frequently found on these birds. Given our discovery of broad interaction between Panamanian tick and avian biodiversity, future work on tick ecology and the

  3. Gradients in the Number of Species at Reef-Seagrass Ecotones Explained by Gradients in Abundance

    PubMed Central

    Tuya, Fernando; Vanderklift, Mathew A.; Wernberg, Thomas; Thomsen, Mads S.

    2011-01-01

    Gradients in the composition and diversity (e.g. number of species) of faunal assemblages are common at ecotones between juxtaposed habitats. Patterns in the number of species, however, can be confounded by patterns in abundance of individuals, because more species tend to be found wherever there are more individuals. We tested whether proximity to reefs influenced patterns in the composition and diversity (‘species density’ = number of species per area and ‘species richness’ = number of species per number of individuals) of prosobranch gastropods in meadows of two seagrasses with different physiognomy: Posidonia and Amphibolis. A change in the species composition was observed from reef-seagrass edges towards the interiors of Amphibolis, but not in Posidonia meadows. Similarly, the abundance of gastropods and species density was higher at edges relative to interiors of Amphibolis meadows, but not in Posidonia meadows. However, species richness was not affected by proximity to reefs in either type of seagrass meadow. The higher number of species at the reef-Amphibolis edge was therefore a consequence of higher abundance, rather than species richness per se. These results suggest that patterns in the composition and diversity of fauna with proximity to adjacent habitats, and the underlying processes that they reflect, likely depend on the physiognomy of the habitat. PMID:21629654

  4. Gradients in the number of species at reef-seagrass ecotones explained by gradients in abundance.

    PubMed

    Tuya, Fernando; Vanderklift, Mathew A; Wernberg, Thomas; Thomsen, Mads S

    2011-01-01

    Gradients in the composition and diversity (e.g. number of species) of faunal assemblages are common at ecotones between juxtaposed habitats. Patterns in the number of species, however, can be confounded by patterns in abundance of individuals, because more species tend to be found wherever there are more individuals. We tested whether proximity to reefs influenced patterns in the composition and diversity ('species density'  =  number of species per area and 'species richness'  =  number of species per number of individuals) of prosobranch gastropods in meadows of two seagrasses with different physiognomy: Posidonia and Amphibolis. A change in the species composition was observed from reef-seagrass edges towards the interiors of Amphibolis, but not in Posidonia meadows. Similarly, the abundance of gastropods and species density was higher at edges relative to interiors of Amphibolis meadows, but not in Posidonia meadows. However, species richness was not affected by proximity to reefs in either type of seagrass meadow. The higher number of species at the reef-Amphibolis edge was therefore a consequence of higher abundance, rather than species richness per se. These results suggest that patterns in the composition and diversity of fauna with proximity to adjacent habitats, and the underlying processes that they reflect, likely depend on the physiognomy of the habitat.

  5. Long-term changes in species composition and relative abundances of sharks at a provisioning site.

    PubMed

    Brunnschweiler, Juerg M; Abrantes, Kátya G; Barnett, Adam

    2014-01-01

    Diving with sharks, often in combination with food baiting/provisioning, has become an important product of today's recreational dive industry. Whereas the effects baiting/provisioning has on the behaviour and abundance of individual shark species are starting to become known, there is an almost complete lack of equivalent data from multi-species shark diving sites. In this study, changes in species composition and relative abundances were determined at the Shark Reef Marine Reserve, a multi-species shark feeding site in Fiji. Using direct observation sampling methods, eight species of sharks (bull shark Carcharhinus leucas, grey reef shark Carcharhinus amblyrhynchos, whitetip reef shark Triaenodon obesus, blacktip reef shark Carcharhinus melanopterus, tawny nurse shark Nebrius ferrugineus, silvertip shark Carcharhinus albimarginatus, sicklefin lemon shark Negaprion acutidens, and tiger shark Galeocerdo cuvier) displayed inter-annual site fidelity between 2003 and 2012. Encounter rates and/or relative abundances of some species changed over time, overall resulting in more individuals (mostly C. leucas) of fewer species being encountered on average on shark feeding dives at the end of the study period. Differences in shark community composition between the years 2004-2006 and 2007-2012 were evident, mostly because N. ferrugineus, C. albimarginatus and N. acutidens were much more abundant in 2004-2006 and very rare in the period of 2007-2012. Two explanations are offered for the observed changes in relative abundances over time, namely inter-specific interactions and operator-specific feeding protocols. Both, possibly in combination, are suggested to be important determinants of species composition and encounter rates, and relative abundances at this shark provisioning site in Fiji. This study, which includes the most species from a spatially confined shark provisioning site to date, suggests that long-term provisioning may result in competitive exclusion among shark

  6. Regional-scale directional changes in abundance of tree species along a temperature gradient in Japan.

    PubMed

    Suzuki, Satoshi N; Ishihara, Masae I; Hidaka, Amane

    2015-09-01

    Climate changes are assumed to shift the ranges of tree species and forest biomes. Such range shifts result from changes in abundances of tree species or functional types. Owing to global warming, the abundance of a tree species or functional type is expected to increase near the colder edge of its range and decrease near the warmer edge. This study examined directional changes in abundance and demographic parameters of forest trees along a temperature gradient, as well as a successional gradient, in Japan. Changes in the relative abundance of each of four functional types (evergreen broad-leaved, deciduous broad-leaved, evergreen temperate conifer, and evergreen boreal conifer) and the demography of each species (recruitment rate, mortality, and population growth rate) were analyzed in 39 permanent forest plots across the Japanese archipelago. Directional changes in the relative abundance of functional types were detected along the temperature gradient. Relative abundance of evergreen broad-leaved trees increased near their colder range boundaries, especially in secondary forests, coinciding with the decrease in deciduous broad-leaved trees. Similarly, relative abundance of deciduous broad-leaved trees increased near their colder range boundaries, coinciding with the decrease in boreal conifers. These functional-type-level changes were mainly due to higher recruitment rates and partly to the lower mortality of individual species at colder sites. This is the first report to show that tree species abundances in temperate forests are changing directionally along a temperature gradient, which might be due to current or past climate changes as well as recovery from past disturbances.

  7. Regional species richness of families and the distribution of abundance and rarity in a local community of forest Hymenoptera

    NASA Astrophysics Data System (ADS)

    Ulrich, Werner

    2005-09-01

    Recent investigations about the relationship between the number of species of taxonomic lineages and regional patterns of species abundances gave indecisive results. Here, it is shown that mean densities of species of a species-rich community of forest Hymenoptera (673 species out of 25 families) were positively related to the number of European species per family. The fraction of abundant species per family declined and the fraction of rare species increased with species richness. Species rich families contained relatively more species, which were present in only one study year (occasional species), and relatively fewer species present during the whole study period (frequent species).

  8. Temporal comparison and predictors of fish species abundance and richness on undisturbed coral reef patches.

    PubMed

    Wagner, Elena L E S; Roche, Dominique G; Binning, Sandra A; Wismer, Sharon; Bshary, Redouan

    2015-01-01

    Large disturbances can cause rapid degradation of coral reef communities, but what baseline changes in species assemblages occur on undisturbed reefs through time? We surveyed live coral cover, reef fish abundance and fish species richness in 1997 and again in 2007 on 47 fringing patch reefs of varying size and depth at Mersa Bareika, Ras Mohammed National Park, Egypt. No major human or natural disturbance event occurred between these two survey periods in this remote protected area. In the absence of large disturbances, we found that live coral cover, reef fish abundance and fish species richness did not differ in 1997 compared to 2007. Fish abundance and species richness on patches was largely related to the presence of shelters (caves and/or holes), live coral cover and patch size (volume). The presence of the ectoparasite-eating cleaner wrasse, Labroides dimidiatus, was also positively related to fish species richness. Our results underscore the importance of physical reef characteristics, such as patch size and shelter availability, in addition to biotic characteristics, such as live coral cover and cleaner wrasse abundance, in supporting reef fish species richness and abundance through time in a relatively undisturbed and understudied region.

  9. Ticks on Deer and Cattle in the Cattle Fever Tick Permanent Quarantine Zone, 2012

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ticks were sampled from hosts in the cattle fever tick permanent quarantine zone along the Texas-Mexico border on five occasions in 2012. Three sample events involved white-tailed deer populations in Zapata and Starr Counties and two were from a cattle herd in Kinney County. Six species of ticks (n ...

  10. Experimentally reducing species abundance indirectly affects food web structure and robustness.

    PubMed

    Barbosa, Milton; Fernandes, G Wilson; Lewis, Owen T; Morris, Rebecca J

    2017-03-01

    Studies on the robustness of ecological communities suggest that the loss or reduction in abundance of individual species can lead to secondary and cascading extinctions. However, most such studies have been simulation-based analyses of the effect of primary extinction on food web structure. In a field experiment we tested the direct and indirect effects of reducing the abundance of a common species, focusing on the diverse and self-contained assemblage of arthropods associated with an abundant Brazilian shrub, Baccharis dracunculifolia D.C. (Asteraceae). Over a 5-month period we experimentally reduced the abundance of Baccharopelma dracunculifoliae (Sternorrhyncha: Psyllidae), the commonest galling species associated with B. dracunculifolia, in 15 replicate plots paired with 15 control plots. We investigated direct effects of the manipulation on parasitoids attacking B. dracunculifoliae, as well as indirect effects (mediated via a third species or through the environment) on 10 other galler species and 50 associated parasitoid species. The experimental manipulation significantly increased parasitism on B. dracunculifoliae in the treatment plots, but did not significantly alter either the species richness or abundance of other galler species. Compared to control plots, food webs in manipulated plots had significantly lower values of weighted connectance, interaction evenness and robustness (measured as simulated tolerance to secondary extinction), even when B. dracunculifoliae was excluded from calculations. Parasitoid species were almost entirely specialized to individual galler species, so the observed effects of the manipulation on food web structure could not have propagated via the documented trophic links. Instead, they must have spread either through trophic links not included in the webs (e.g. shared predators) or non-trophically (e.g. through changes in habitat availability). Our results highlight that the inclusion of both trophic and non

  11. Description of the immature stages and redescription of the female of Ixodes schulzei Aragão & Fonseca, 1951 (Acari: Ixodidae), an endemic tick species of Brazil.

    PubMed

    Barros-Battesti, Darci M; Onofrio, Valeria C; Faccini, João L H; Labruna, Marcelo B; Arruda-Santos, Ana D; Giacomin, Flávia G

    2007-11-01

    Ixodes schulzei Aragão & Fonseca, 1951 is a tick endemic to Brazil, where nine species of Ixodes Latreille, 1796 are currently known to occur. Larvae, nymphs and females of I. schulzei were obtained from a laboratory colony originating from an engorged female collected on a free-living water rat Nectomys squamipes from the Santa Branca municipality, São Paulo State. Only female ticks were obtained from engorged nymphs. Unfed immature and female adult specimens were measured and the descriptions were based on optical and scanning electron microscopy, as were drawings of some features of the larva. Both immature stages present the very long palpi and basis capituli, and the female has large, contiguous porose areas. However, the basis capituli is triangular, with a slight central elevation in the larva and nymph, whereas in the female this area is depressed. The I. schulzei types deposited at the FIOCRUZ (Instituto Oswaldo Cruz) were also examined, as was other material from collections, such as the IBSP (Coleção Acarológica do Instituto Butantan), CNC-FMVZ/USP (Coleção Nacional de Carrapatos da Faculdade de Medicina Veterinária e Zootecnia da USP) and USNTC (United States National Tick Collection). In addition, the relationship between I. schulzei and other immature neotropical species of Ixodes is discussed.

  12. Ixodid tick infestation in cattle and wild animals in Maswa and Iringa, Tanzania.

    PubMed

    Kwak, You Shine; Kim, Tae Yun; Nam, Sung-Hyun; Lee, In-Yong; Kim, Hyung-Pyo; Mduma, Simon; Keyyu, Julius; Fyumagwa, Robert; Yong, Tai-Soon

    2014-10-01

    Ticks and tick-borne diseases are important in human and livestock health worldwide. In November 2012, ixodid ticks were collected and identified morphologically from cattle and wild animals in the Maswa district and Iringa urban, Tanzania. Amblyomma gemma, A. lepidum, and A. variegatum were identified from Maswa cattle, and A. variegatum was the predominant species. A. marmoreum, Hyalomma impeltatum, and Rhipicephalus pulchellus were identified from Iringa cattle in addition to the above 3 Amblyomma species, and A. gemma was the most abundant species. Total 4 Amblyomma and 6 Rhipicephalus species were identified from wild animals of the 2 areas. A. lepidum was predominant in Maswa buffaloes, whereas A. gemma was predominant in Iringa buffaloes. Overall, A. variegatum in cattle was predominant in the Maswa district and A. gemma was predominant in Iringa, Tanzania.

  13. Absence of the symbiont Candidatus Midichloria mitochondrii in the mitochondria of the tick Ixodes holocyclus.

    PubMed

    Beninati, Tiziana; Riegler, Markus; Vilcins, Inger-Marie E; Sacchi, Luciano; McFadyen, Raelene; Krockenberger, Mark; Bandi, Claudio; O'Neill, Scott L; Lo, Nathan

    2009-10-01

    Candidatus Midichloria mitochondrii (M. mitochondrii) belongs to a novel clade of bacteria within the order Rickettsiales. Recent PCR-based screening studies indicate that it is present in a number of blood-sucking arthropods, as well as the blood of some vertebrates. Its medical and veterinary significance remains to be determined. Electron microscopic examinations of M. mitochondrii have thus far been conducted on two infected tick species. Remarkably, the bacterium was found in abundance within the mitochondria of the ovarian cells of each tick species. This makes it the only characterized bacterium able to invade the mitochondria of any multicellular organism. To examine whether mitochondrial invasion is a consistent characteristic of M. mitochondrii, we examined two tick species found in Eastern Australia. One of these species, Ixodes holocyclus, was infected with two M. mitochondrii strains; however, no bacteria were seen in the mitochondria. Comparative studies involving these strains may shed light on the unique phenomenon of mitochondrial invasion.

  14. Early MESSENGER Results for Less Abundant or Weakly Emitting Species in Mercury's Exosphere

    NASA Technical Reports Server (NTRS)

    Vervack, Ronald J., Jr.; McClintock, William E.; Killen, Rosemary M.; Sprague, Ann L.; Burger, Matthew H.; Merkel, Aimee W.; Sarantos, Menelaos

    2011-01-01

    Now that the Messenger spacecraft is in orbit about Mercury, the extended observing time enables searches for exospheric species that are less abundant or weakly emitting compared with those for which emission has previously been detected. Many of these species cannot be observed from the ground because of terrestrial atmospheric absorption. We report here on the status of MESSENGER orbital-phase searches for additional species in Mercury's exosphere.

  15. Molecular identification of tick-borne pathogens in Nigerian ticks.

    PubMed

    Ogo, Ndudim Isaac; de Mera, Isabel G Fernández; Galindo, Ruth C; Okubanjo, Oluyinka O; Inuwa, Hauwa Mairo; Agbede, Rowland I S; Torina, Alessandra; Alongi, Angelina; Vicente, Joaquín; Gortázar, Christian; de la Fuente, José

    2012-07-06

    A molecular epidemiology investigation was undertaken in two Nigerian states (Plateau and Nassarawa) to determine the prevalence of pathogens of veterinary and public health importance associated with ticks collected from cattle and dogs using PCR, cloning and sequencing or reverse line blot techniques. A total of 218 tick samples, Amblyomma variegatum (N=153), Rhipicephalus (Boophilus) decoloratus (N=45), and Rhipicephalus sanguineus (N=20) were sampled. Pathogens identified in ticks included piroplasmids (Babesia spp., Babesia bigemina and Babesia divergens), Anaplasma marginale and Rickettsia africae. Piroplasmids were identified in A. variegatum, A. marginale was found in R. decoloratus, while R. africae was detected in all tick species examined. Ehrlichia spp. and Theileria spp. were not identified in any of the ticks examined. Of the 218 ticks examined, 33 (15.1%) contained pathogen DNA, with the presence of B. divergens and R. africae that are zoonotic pathogens of public health and veterinary importance. The variety of tick-borne pathogens identified in this study suggests a risk for the emergence of tick-borne diseases in domestic animals and humans, especially amongst the Fulani pastoralists in Plateau and Nassarawa states of Nigeria.

  16. Molecular survey of hard ticks in endemic areas of tick-borne diseases in China.

    PubMed

    Lu, Xin; Lin, Xian-Dan; Wang, Jian-Bo; Qin, Xin-Cheng; Tian, Jun-Hua; Guo, Wen-Ping; Fan, Fei-Neng; Shao, Renfu; Xu, Jianguo; Zhang, Yong-Zhen

    2013-06-01

    Over the past several years, there was a substantial increase in the number of cases of known and novel tick-borne infections in humans in China. To better understand the ticks associated with these infections, we collected hard ticks from animals or around livestock shelters in 29 localities in 5 provinces (Beijing, Henan, Hubei, Inner Mongolia, and Zhejiang) where cases of tick-borne illness were reported. We collected 2950 hard ticks representing 7 species of 4 genera (Dermacentor sinicus, Haemaphysalis flava, Haemaphysalis longicornis, Ixodes granulatus, Ixodes persulcatus, Rhipicephalus microplus, and Rhipicephalus sanguineus). These ticks were identified to species using morphological characters initially. We then sequenced the mitochondrial small subunit rRNA (12S rRNA) gene, cytochrome oxidase subunit 1 (COI) gene, and the second internal transcribed spacer (ITS2) gene of these ticks, and conducted phylogenetic analyses. Our analyses showed that the molecular and morphological data are consistent in the identification of the 7 tick species. Furthermore, all these 7 tick species from China were genetically closely related to the same species or related species found outside China. Rapid and accurate identification and long-term monitoring of these ticks will be of significance to the prevention and control of tick-borne diseases in China.

  17. Cattle ticks in Cameroon: is Rhipicephalus (Boophilus) microplus absent in Cameroon and the Central African region?

    PubMed

    Awa, D N; Adakal, H; Luogbou, N D D; Wachong, K H; Leinyuy, I; Achukwi, M D

    2015-03-01

    In most parts of the world, ticks are rapidly developing resistance to commonly used acaricides thus rendering control difficult. This constraint is further compounded by the introduction of new species in areas where they did not exist before. Such is the case with the introduction into and rapid spread of Rhipicephalus (Boophilus) microplus in some countries of West Africa. With the looming threat of its further spread in the region, the objective of the present study was to update knowledge on cattle ticks in Cameroon. Among 19,189 ticks collected monthly from 60 animals in 5 herds from March 2012 to February 2013, Rh. (B.) decoloratus was the most abundant species with a relative prevalence of 62.2%, followed by Amblyomma variegatum (28.4%), Rh. (B.) annulatus (0.2%), Rh. (B.) geigyi (0.03%), other Rhipicephalus spp. (8.4%) and Hyalomma spp. (0.3%). Rh. (B.) decoloratus and A. variegatum were also the most widely distributed in space. Infestation rate was generally high, with average tick count/animal of about 80 during peak periods. Tick distribution and abundance in the different sites was as varied as the underlying factors, among which the most important were management systems and climatic factors. The effects of rainfall and temperature were confounded by other factors and difficult to evaluate. However, it appears tick development depends among other factors, on a humidity threshold, above which there is not much more effect. Rh. microplus was not found during this study, but more extensive tick collections have to be done to confirm this. In conclusion, cattle tick infestation in Cameroon remains an important cause for concern. Farmers need assistance in the use and management of acaricides in order to increase their efficiency and reduce the development of resistance. Although Rh. microplus was not found, its introduction from other West African countries is imminent if adequate measures, especially in the control and limitation of animal movements

  18. Vaccinomics, the new road to tick vaccines.

    PubMed

    de la Fuente, José; Merino, Octavio

    2013-12-05

    Ticks are a threat to human and animal health worldwide. Ticks are considered to be second worldwide to mosquitoes as vectors of human diseases, the most important vectors of diseases that affect cattle industry worldwide and important vectors of diseases affecting pets. Tick vaccines are a cost-effective and environmentally friendly alternative to protect against tick-borne diseases through the control of vector infestations and reducing pathogen infection and transmission. These premises stress the need for developing improved tick vaccines in a more efficient way. In this context, development of improved vaccines for tick-borne diseases will be greatly enhanced by vaccinomics approaches starting from the study of tick–host–pathogen molecular interactions and ending in the characterization and validation of vaccine formulations. The discovery of new candidate vaccine antigens for the control of tick infestations and pathogen infection and transmission requires the development of effective screening platforms and algorithms that allow the analysis and validation of data produced by systems biology approaches to tick research. Tick vaccines that affect both tick infestations and pathogen transmission could be used to vaccinate human and animal populations at risk and reservoir species to reduce host exposure to ticks while reducing the number of infected ticks and their vectorial capacity for pathogens that affect human and animal health worldwide.

  19. Do abundance distributions and species aggregation correctly predict macroecological biodiversity patterns in tropical forests?

    PubMed Central

    Wiegand, Thorsten; Lehmann, Sebastian; Huth, Andreas; Fortin, Marie‐Josée

    2016-01-01

    Abstract Aim It has been recently suggested that different ‘unified theories of biodiversity and biogeography’ can be characterized by three common ‘minimal sufficient rules’: (1) species abundance distributions follow a hollow curve, (2) species show intraspecific aggregation, and (3) species are independently placed with respect to other species. Here, we translate these qualitative rules into a quantitative framework and assess if these minimal rules are indeed sufficient to predict multiple macroecological biodiversity patterns simultaneously. Location Tropical forest plots in Barro Colorado Island (BCI), Panama, and in Sinharaja, Sri Lanka. Methods We assess the predictive power of the three rules using dynamic and spatial simulation models in combination with census data from the two forest plots. We use two different versions of the model: (1) a neutral model and (2) an extended model that allowed for species differences in dispersal distances. In a first step we derive model parameterizations that correctly represent the three minimal rules (i.e. the model quantitatively matches the observed species abundance distribution and the distribution of intraspecific aggregation). In a second step we applied the parameterized models to predict four additional spatial biodiversity patterns. Results Species‐specific dispersal was needed to quantitatively fulfil the three minimal rules. The model with species‐specific dispersal correctly predicted the species–area relationship, but failed to predict the distance decay, the relationship between species abundances and aggregations, and the distribution of a spatial co‐occurrence index of all abundant species pairs. These results were consistent over the two forest plots. Main conclusions The three ‘minimal sufficient’ rules only provide an incomplete approximation of the stochastic spatial geometry of biodiversity in tropical forests. The assumption of independent interspecific placements is most

  20. Candidatus Bartonella antechini: a novel Bartonella species detected in fleas and ticks from the yellow-footed antechinus (Antechinus flavipes), an Australian marsupial.

    PubMed

    Kaewmongkol, Gunn; Kaewmongkol, Sarawan; Owen, Helen; Fleming, Patricia A; Adams, Peter J; Ryan, Una; Irwin, Peter J; Fenwick, Stanley G

    2011-05-05

    Bartonella are fastidious, Gram-negative, aerobic bacilli belonging to the Alphaproteobacteria group. In the last ten years, the discovery of new Bartonella species from a variety of mammalian hosts, arthropod vectors and geographical areas has increased. More than 20 species of Bartonella have been identified, of which approximately thirteen are associated with disease in humans and animals. Recently, four novel species of Bartonella were isolated from mammalian hosts in Australia: Bartonella australis from eastern grey kangaroos (Macropus giganteus) and Bartonella rattaustraliani, Bartonella queenslandensis and Bartonella coopersplainsensis from rodents. Bartonella-like organisms have also been detected from Ixodes tasmani ticks collected from koalas (Phascolarctos cinereus). However, very little is known about Bartonella spp. in other marsupials in Australia. We report the identification of a novel Bartonella species detected from fleas (Acanthopsylla jordani) and ticks (Ixodes antechini) collected from a small carnivorous marsupial, Antechinus flavipes (Mardos or Yellow-footed antechinus) in the southwest of Western Australia. New nested-PCRs targeting the gltA gene and the ribosomal ITS region were developed as part of the present study. DNA sequencing of the 16S rRNA, gltA, ftsZ and rpoB genes and the ribosomal ITS region revealed that this detection is a distinct Bartonella species and is related to B. australis isolated from kangaroos. This is the first report of two different possible arthropod vectors in Australia (ticks and fleas) being infected with the same species of Bartonella. We propose the name Candidatus Bartonella antechini n. sp. for the recently characterized organism.

  1. Evolutionary patterns of range size, abundance and species richness in Amazonian angiosperm trees

    PubMed Central

    Chave, Jérôme

    2016-01-01

    Amazonian tree species vary enormously in their total abundance and range size, while Amazonian tree genera vary greatly in species richness. The drivers of this variation are not well understood. Here, we construct a phylogenetic hypothesis that represents half of Amazonian tree genera in order to contribute to explaining the variation. We find several clear, broad-scale patterns. Firstly, there is significant phylogenetic signal for all three characteristics; closely related genera tend to have similar numbers of species and similar mean range size and abundance. Additionally, the species richness of genera shows a significant, negative relationship with the mean range size and abundance of their constituent species. Our results suggest that phylogenetically correlated intrinsic factors, namely traits of the genera themselves, shape among lineage variation in range size, abundance and species richness. We postulate that tree stature may be one particularly relevant trait. However, other traits may also be relevant, and our study reinforces the need for ambitious compilations of trait data for Amazonian trees. In the meantime, our study shows how large-scale phylogenies can help to elucidate, and contribute to explaining, macroecological and macroevolutionary patterns in hyperdiverse, yet poorly understood regions like the Amazon Basin. PMID:27651991

  2. Evolutionary patterns of range size, abundance and species richness in Amazonian angiosperm trees.

    PubMed

    Dexter, Kyle; Chave, Jérôme

    2016-01-01

    Amazonian tree species vary enormously in their total abundance and range size, while Amazonian tree genera vary greatly in species richness. The drivers of this variation are not well understood. Here, we construct a phylogenetic hypothesis that represents half of Amazonian tree genera in order to contribute to explaining the variation. We find several clear, broad-scale patterns. Firstly, there is significant phylogenetic signal for all three characteristics; closely related genera tend to have similar numbers of species and similar mean range size and abundance. Additionally, the species richness of genera shows a significant, negative relationship with the mean range size and abundance of their constituent species. Our results suggest that phylogenetically correlated intrinsic factors, namely traits of the genera themselves, shape among lineage variation in range size, abundance and species richness. We postulate that tree stature may be one particularly relevant trait. However, other traits may also be relevant, and our study reinforces the need for ambitious compilations of trait data for Amazonian trees. In the meantime, our study shows how large-scale phylogenies can help to elucidate, and contribute to explaining, macroecological and macroevolutionary patterns in hyperdiverse, yet poorly understood regions like the Amazon Basin.

  3. Predators reduce abundance and species richness of coral reef fish recruits via non-selective predation

    NASA Astrophysics Data System (ADS)

    Heinlein, J. M.; Stier, A. C.; Steele, M. A.

    2010-06-01

    Predators have important effects on coral reef fish populations, but their effects on community structure have only recently been investigated and are not yet well understood. Here, the effect of predation on the diversity and abundance of young coral reef fishes was experimentally examined in Moorea, French Polynesia. Effects of predators were quantified by monitoring recruitment of fishes onto standardized patch reefs in predator-exclosure cages or uncaged reefs. At the end of the 54-day experiment, recruits were 74% less abundant on reefs exposed to predators than on caged ones, and species richness was 42% lower on reefs exposed to predators. Effects of predators varied somewhat among families, however, rarefaction analysis indicated that predators foraged non-selectively among species. These results indicate that predation can alter diversity of reef fish communities by indiscriminately reducing the abundance of fishes soon after settlement, thereby reducing the number of species present on reefs.

  4. Soil biota effects on local abundances of three grass species along a land-use gradient.

    PubMed

    Heinze, J; Werner, T; Weber, E; Rillig, M C; Joshi, J

    2015-09-01

    Biotic plant-soil interactions and land-use intensity are known to affect plant individual fitness as well as competitiveness and therefore plant-species abundances in communities. Therefore, a link between soil biota and land-use intensity on local abundance of plant species in grasslands can be expected. In two greenhouse experiments, we investigated the effects of soil biota from grassland sites differing in land-use intensity on three grass species that vary in local abundances along this land-use gradient. We were interested in those soil-biota effects that are associated with land-use intensity, and whether these effects act directly or indirectly. Therefore, we grew the three plant species in two separate experiments as single individuals and in mixtures and compared their performance. As single plants, all three grasses showed a similar performance with and without soil biota. In contrast, in mixtures growth of the species in response to the presence or absence of soil biota differed. This resulted in different soil-biota effects that tend to correspond with patterns of species-specific abundances in the field for two of the three species tested. Our results highlight the importance of indirect interactions between plants and soil microorganisms and suggest that combined effects of soil biota and plant-plant interactions are involved in structuring plant communities. In conclusion, our experiments suggest that soil biota may have the potential to alter effects of plant-plant interactions and therefore influence plant-species abundances and diversity in grasslands.

  5. Reverse transcription PCR-based detection of Crimean-Congo hemorrhagic fever virus isolated from ticks of domestic ruminants in Kurdistan province of Iran.

    PubMed

    Fakoorziba, Mohammad Reza; Golmohammadi, Parvaneh; Moradzadeh, Rahmatollah; Moemenbellah-Fard, Mohammad Djaefar; Azizi, Kourosh; Davari, Behrooz; Alipour, Hamzeh; Ahmadnia, Sara; Chinikar, Sadegh

    2012-09-01

    Crimean-Congo hemorrhagic fever (CCHF) is a potentially fatal viral vector-borne zoonosis which has a mortality rate of up to 30% without treatment in humans. CCHF virus is transmitted to humans by ticks, predominantly from the Hyalomma genus. Following the report of two confirmed and one suspected death due to CCHF virus in Kurdistan province of Iran in 2007, this study was undertaken to determine the fauna of hard ticks on domestic ruminants (cattle, sheep, and goats) and their possible infection with CCHF virus using reverse transcription PCR technique. This is the first detection of CCHF virus in ticks from the Kurdistan province of Iran. Overall, 414 ixodid ticks were collected from two districts in this province. They represented four genera from which 10 separate species were identified. The Hyalomma genus was the most abundant tick genus (70%). It was the only genus shown to be infected with the CCHF virus using RT-PCR technique. The number of ticks positive for CCHF virus was 5 out of 90 (5.6%) adult ticks. The three remaining genera (Haemaphysalis, Rhipicephalus, and Dermacentor) were all negative following molecular survey. Four of the five virally-infected ticks were from cattle mainly in the Sanandaj district. We concluded that CCHF virus is present in the Hyalomma ticks on domestic ruminants (cattle) in Kurdistan province of Iran.

  6. Habitat selection determines abundance, richness and species composition of beetles in aquatic communities.

    PubMed

    Binckley, Christopher A; Resetarits, William J

    2005-09-22

    Distribution and abundance patterns at the community and metacommunity scale can result from two distinct mechanisms. Random dispersal followed by non-random, site-specific mortality (species sorting) is the dominant paradigm in community ecology, while habitat selection provides an alternative, largely unexplored, mechanism with different demographic consequences. Rather than differential mortality, habitat selection involves redistribution of individuals among habitat patches based on perceived rather than realized fitness, with perceptions driven by past selection. In particular, habitat preferences based on species composition can create distinct patterns of positive and negative covariance among species, generating more complex linkages among communities than with random dispersal models. In our experiments, the mere presence of predatory fishes, in the absence of any mortality, reduced abundance and species richness of aquatic beetles by up to 80% in comparison with the results from fishless controls. Beetle species' shared habitat preferences generated distinct patterns of species richness, species composition and total abundance, matching large-scale field patterns previously ascribed to random dispersal and differential mortality. Our results indicate that landscape-level patterns of distribution and species diversity can be driven to a large extent by habitat selection behaviour, a critical, but largely overlooked, mechanism of community and metacommunity assembly.

  7. Environmental correlates of species rank – abundance distributions in global drylands

    PubMed Central

    Ulrich, Werner; Soliveres, Santiago; Thomas, Andrew D.; Dougill, Andrew J.; Maestre, Fernando T.

    2016-01-01

    Theoretical models predict lognormal species abundance distributions (SADs) in stable and productive environments, with log-series SADs in less stable, dispersal driven communities. We studied patterns of relative species abundances of perennial vascular plants in global dryland communities to: i) assess the influence of climatic and soil characteristics on the observed SADs, ii) infer how environmental variability influences relative abundances, and iii) evaluate how colonisation dynamics and environmental filters shape abundance distributions. We fitted lognormal and log-series SADs to 91 sites containing at least 15 species of perennial vascular plants. The dependence of species relative abundances on soil and climate variables was assessed using general linear models. Irrespective of habitat type and latitude, the majority of the SADs (70.3%) were best described by a lognormal distribution. Lognormal SADs were associated with low annual precipitation, higher aridity, high soil carbon content, and higher variability of climate variables and soil nitrate. Our results do not corroborate models predicting the prevalence of log-series SADs in dryland communities. As lognormal SADs were particularly associated with sites with drier conditions and a higher environmental variability, we reject models linking lognormality to environmental stability and high productivity conditions. Instead our results point to the prevalence of lognormal SADs in heterogeneous environments, allowing for more evenly distributed plant communities, or in stressful ecosystems, which are generally shaped by strong habitat filters and limited colonisation. This suggests that drylands may be resilient to environmental changes because the many species with intermediate relative abundances could take over ecosystem functioning if the environment becomes suboptimal for dominant species. PMID:27330404

  8. Using species abundance distribution models and diversity indices for biogeographical analyses

    NASA Astrophysics Data System (ADS)

    Fattorini, Simone; Rigal, François; Cardoso, Pedro; Borges, Paulo A. V.

    2016-01-01

    We examine whether Species Abundance Distribution models (SADs) and diversity indices can describe how species colonization status influences species community assembly on oceanic islands. Our hypothesis is that, because of the lack of source-sink dynamics at the archipelago scale, Single Island Endemics (SIEs), i.e. endemic species restricted to only one island, should be represented by few rare species and consequently have abundance patterns that differ from those of more widespread species. To test our hypothesis, we used arthropod data from the Azorean archipelago (North Atlantic). We divided the species into three colonization categories: SIEs, archipelagic endemics (AZEs, present in at least two islands) and native non-endemics (NATs). For each category, we modelled rank-abundance plots using both the geometric series and the Gambin model, a measure of distributional amplitude. We also calculated Shannon entropy and Buzas and Gibson's evenness. We show that the slopes of the regression lines modelling SADs were significantly higher for SIEs, which indicates a relative predominance of a few highly abundant species and a lack of rare species, which also depresses diversity indices. This may be a consequence of two factors: (i) some forest specialist SIEs may be at advantage over other, less adapted species; (ii) the entire populations of SIEs are by definition concentrated on a single island, without possibility for inter-island source-sink dynamics; hence all populations must have a minimum number of individuals to survive natural, often unpredictable, fluctuations. These findings are supported by higher values of the α parameter of the Gambin mode for SIEs. In contrast, AZEs and NATs had lower regression slopes, lower α but higher diversity indices, resulting from their widespread distribution over several islands. We conclude that these differences in the SAD models and diversity indices demonstrate that the study of these metrics is useful for

  9. Tick Removal

    MedlinePlus

    ... There are several tick removal devices on the market, but a plain set of fine-tipped tweezers ... for Disease Control and Prevention National Center for Emerging and Zoonotic Infectious Diseases (NCEZID) Division of Vector- ...

  10. Habitat partitioning by five congeneric and abundant Choerodon species (Labridae) in a large subtropical marine embayment

    NASA Astrophysics Data System (ADS)

    Fairclough, D. V.; Clarke, K. R.; Valesini, F. J.; Potter, I. C.

    2008-04-01

    The habitats occupied by the juveniles and adults of five morphologically similar, diurnally active and abundant Choerodon species in the large subtropical environment of Shark Bay, a "World Heritage Property" on the west coast of Australia, have been determined. The densities of the two life cycle stages of each Choerodon species in those habitats were used in various analyses to test the hypotheses that: (1) habitats are partitioned among these species and between their juveniles and adults; (2) such habitat partitioning is greatest in the case of the two Western Australian endemic species, i.e. Choerodon rubescens and Choerodon cauteroma; and (3) the extent of habitat partitioning between both of these two species and the only species that is widely distributed in the Indo-West Pacific, i.e. Choerodon schoenleinii, will be less pronounced. Initially, catches of each of the five congeneric species, obtained during other studies in Shark Bay by angling, spearfishing and otter trawling, were collated to elucidate the broad distribution of these species in that embayment. Underwater visual census was then used to determine the densities of the juveniles and adults of each Choerodon species at sites representing the four habitat types in which one or more of these species had been caught, i.e. reefs in marine waters at the western boundary of the bay and seagrass, reefs and rocky shorelines in the two inner gulfs. The compositions of the Choerodon species over marine (entrance channel) reefs and in seagrass were significantly different and each differed significantly from those in both inner gulf reefs and rocky shorelines, which were, however, not significantly different. Choerodon rubescens was restricted to exposed marine reefs, and thus occupied a different habitat and location of the bay than C. cauteroma, the other endemic species, which was almost exclusively confined to habitats found in the inner gulfs. Choerodon cauteroma differed from other Choerodon

  11. Porphyromonas gingivalis is the most abundant species detected in coronary and femoral arteries

    PubMed Central

    Mougeot, J-L. C.; Stevens, C. B.; Paster, B. J.; Brennan, M. T.; Lockhart, P. B.; Mougeot, F. K. B

    2017-01-01

    ABSTRACT An association between oral bacteria and atherosclerosis has been postulated. A limited number of studies have used 16S RNA gene sequencing-based metagenomics approaches to identify bacteria at the species level from atherosclerotic plaques in arterial walls. The objective of this study was to establish detailed oral microbiome profiles, at both genus and species level, of clinically healthy coronary and femoral artery tissues from patients with atherosclerosis. Tissue specimens were taken from clinically non-atherosclerotic areas of coronary or femoral arteries used for attachment of bypass grafts in 42 patients with atherosclerotic cardiovascular disease. Bacterial DNA was sequenced using the MiSeq platform, and sequence reads were screened in silico for nearly 600 oral species using the HOMINGS ProbeSeq species identification program. The number of sequence reads matched to species or genera were used for statistical analyses. A total of 230 and 118 species were detected in coronary and femoral arteries, respectively. Unidentified species detected by genus-specific probes consisted of 45 and 30 genera in coronary and in femoral artery tissues, respectively. Overall, 245 species belonging to 95 genera were detected in coronary and femoral arteries combined. The most abundant species were Porphyromonas gingivalis, Enterococcus faecalis, and Finegoldia magna based on species probes. Porphyromonas, Escherichia, Staphylococcus, Pseudomonas, and Streptococcus genera represented 88.5% mean relative abundance based on combined species and genus probe detections. Porphyromonas was significantly more abundant than Escherichia (i.e. 46.8% vs. 19.3%; p = 0.0005). This study provides insight into the presence and types of oral microbiome bacterial species found in clinically non-atherosclerotic arteries. PMID:28326156

  12. Tree species composition affects the abundance of rowan (Sorbus aucuparia L.) in urban forests in Finland.

    PubMed

    Hamberg, Leena; Lehvävirta, Susanna; Kotze, D Johan; Heikkinen, Juha

    2015-03-15

    Recent studies have shown a considerable increase in the abundance of rowan (Sorbus aucuparia) saplings in urban forests in Finland, yet the reasons for this increase are not well understood. Here we investigated whether canopy cover or tree species composition, i.e., the basal areas of different tree species in Norway spruce dominated urban forests, affects the abundances of rowan seedlings, saplings and trees. Altogether 24 urban forest patches were investigated. We sampled the number of rowan and other saplings, and calculated the basal areas of trees. We showed that rowan abundance was affected by tree species composition. The basal area of rowan trees (≥ 5 cm in diameter at breast height, dbh) decreased with increasing basal area of Norway spruce, while the cover of rowan seedlings increased with an increase in Norway spruce basal area. However, a decrease in the abundance of birch (Betula pendula) and an increase in the broad-leaved tree group (Acer platanoides, Alnus glutinosa, Alnus incana, Amelanchier spicata, Prunus padus, Quercus robur, Rhamnus frangula and Salix caprea) coincided with a decreasing number of rowans. Furthermore, rowan saplings were scarce in the vicinity of mature rowan trees. Although it seems that tree species composition has an effect on rowan, the relationship between rowan saplings and mature trees is complex, and therefore we conclude that regulating tree species composition is not an easy way to keep rowan thickets under control in urban forests in Finland.

  13. A Spectroscopic Survey of Metallic Species Abundances in the Lunar Atmosphere

    NASA Astrophysics Data System (ADS)

    Flynn, B. C.; Stern, S. A.

    1996-12-01

    The first results of an ongoing effort to search for new species in the lunar atmosphere are presented. The observations in terms of the degree to which atomic metal abundances in the lunar atmosphere are stoichiometric, that is, proportional to surface abundances (as the Na:K ratio is), are discussed. Na and K are the only atmospheric constituents to have been observed from Earth, but Apollo sample returns established that a variety of species are more abundant in the lunar surface than either Na or K. Simple stoichiometric arguments (i.e., assuming atmospheric production proportional to surface abundance) predict that relatively abundant lunar surface constituents such as Si, Al, Ca, Mg, Fe, and Ti should be more abundant in the lunar atmosphere than either Na or K. The 2.7-m coudé and 2.1-m cassegrain echelle spectrographs at the University of Texas McDonald Observatory were used to investigate this hypothesis by searching for solar resonant scattering lines of nine metallic species between 3700 and 9700 Å. Spectra were taken 20 arcsec above the apparent subsolar limb of the Moon near quarter phase on 30 July 1994 and 10-12 March 1995. Upper limits were obtained for the first time for the abundant lunar surface species Si, Al, Ca, Fe, and Ti, as well as Ba and the alkalis Li, Rb, and Cs. In the cases of Si, Ca, Fe, and Ti, the derived upper limits are more than an order of magnitude lower than the simple stoichiometric model predicts. The upper limits for Li and Al are less constraining. The Ba, Rb, and Cs upper limits lead to the conclusion that those species are not stoichiometrically overabundant above the detection threshold in the atmosphere. It is concluded that the stoichiometric Na:K ratio is peculiar in that the mechanism(s) that produce the lunar Na and K atmosphere somehow favor those atomic species over many more or comparably abundant lunar surface species.

  14. Tick-borne pathogens and the vector potential of ticks in China.

    PubMed

    Yu, Zhijun; Wang, Hui; Wang, Tianhong; Sun, Wenying; Yang, Xiaolong; Liu, Jingze

    2015-01-14

    Ticks, as obligate blood-sucking ectoparasites, attack a broad range of vertebrates and transmit a great diversity of pathogenic microorganisms. They are considered second only to mosquitoes as vectors of human disease, and the most important vector of pathogens of domestic and wild animals. Of the 117 described species in the Chinese tick fauna, 60 are known to transmit one or more diseases: 36 species isolated within China and 24 species isolated outside China. Moreover, 38 of these species carry multiple pathogens, indicating the potentially vast role of these vectors in transmitting pathogens. Spotted fever is the most common tick-borne disease, and is carried by at least 27 tick species, with Lyme disease and human granulocytic anaplasmosis ranked as the second and third most widespread tick-borne diseases, carried by 13 and 10 species, respectively. Such knowledge provides us with clues for the identification of tick-associated pathogens and suggests ideas for the control of tick-borne diseases in China. However, the numbers of tick-associated pathogens and tick-borne diseases in China are probably underestimated because of the complex distribution and great diversity of tick species in this country.

  15. Does beach nourishment have long-term effects on intertidal macroinvertebrate species abundance?

    NASA Astrophysics Data System (ADS)

    Leewis, Lies; van Bodegom, Peter M.; Rozema, Jelte; Janssen, Gerard M.

    2012-11-01

    Coastal squeeze is the largest threat for sandy coastal areas. To mitigate seaward threats, erosion and sea level rise, sand nourishment is commonly applied. However, its long-term consequences for macroinvertebrate fauna, critical to most ecosystem services of sandy coasts, are still unknown. Seventeen sandy beaches - nourished and controls - were sampled along a chronosequence to investigate the abundance of four dominant macrofauna species and their relations with nourishment year and relevant coastal environmental variables. Dean's parameter and latitude significantly explained the abundance of the spionid polychaete Scolelepis squamata, Beach Index (BI), sand skewness, beach slope and latitude explained the abundance of the amphipod Haustorius arenarius and Relative Tide Range (RTR), recreation and sand sorting explained the abundance of Bathyporeia sarsi. For Eurydice pulchra, no environmental variable explained its abundance. For H. arenarius, E. pulchra and B. sarsi, there was no relation with nourishment year, indicating that recovery took place within a year after nourishment. Scolelepis squamata initially profited from the nourishment with "over-recolonisation". This confirms its role as an opportunistic species, thereby altering the initial community structure on a beach after nourishment. We conclude that the responses of the four dominant invertebrates studied in the years following beach nourishment are species specific. This shows the importance of knowing the autecology of the sandy beach macroinvertebrate fauna in order to be able to mitigate the effects of beach nourishment and other environmental impacts.

  16. Nutrient availability modifies species abundance and community structure of Fucus-associated littoral benthic fauna.

    PubMed

    Korpinen, Samuli; Jormalainen, Veijo; Pettay, Esko

    2010-01-01

    The brown alga Fucus vesiculosus is a foundation species in the Baltic Sea littoral, hosting a rich faunal community. We compared the species composition and diversity of invertebrate macrofauna living on F. vesiculosus between sites differing in their eutrophication status and exposure to waves at three different times during a season. We determined the size, nitrogen and phlorotannin content of the alga. The invertebrate community differed substantially between sites near fish farms and those in more pristine environment. Snails and bivalves were more abundant on the Fucus stands near fish farms than on control stands, where crustaceans were more abundant. The abundance of molluscs decreased with the increasing shore exposure, while gammaridean amphipods dominated on the exposed shores. Abundance of several taxa increased during the proceeding growing season. The density of the most important herbivore of F. vesiculosus, Idotea balthica, varied 100-fold during the season being the lowest in June and the highest in August when the generation born in the summer started to feed on Fucus. Thus, the diversity and composition of Fucus-associated invertebrate fauna varies both with environmental conditions of the stand and seasonally. Although the negative effects of eutrophication on distribution and abundance of Fucus stands are well documented, a moderate increase of nutrients was found to increase the species richness of Fucus-associated fauna in early summer.

  17. Tick infestations (Acari: Ixodidae) on three lizard species from Seraidi (Annaba District), northeastern Algeria.

    PubMed

    Soualah-Alila, Hana; Bouslama, Zihad; Amr, Zuhair; Bani Hani, Rihan

    2015-09-01

    Parasitism of Ixodes ricinus on three species of lizards (Psammodromus algirus, Podarcis vaucheri and Timon pater) in northeastern Algeria was studied. Psammodromus algirus was the most preferred host, T. pater was least preferred. Nymphs of I. ricinus were found attached to lizards from March to August in various numbers. Most nymphs were collected during March, April and June for P. algirus, and most larvae from April until August. Larval stages were found to be mostly associated with P. vaucheri during the study period, with the highest number of recovered larvae in June.

  18. Estimating Lion Abundance using N-mixture Models for Social Species

    PubMed Central

    Belant, Jerrold L.; Bled, Florent; Wilton, Clay M.; Fyumagwa, Robert; Mwampeta, Stanslaus B.; Beyer, Dean E.

    2016-01-01

    Declining populations of large carnivores worldwide, and the complexities of managing human-carnivore conflicts, require accurate population estimates of large carnivores to promote their long-term persistence through well-informed management We used N-mixture models to estimate lion (Panthera leo) abundance from call-in and track surveys in southeastern Serengeti National Park, Tanzania. Because of potential habituation to broadcasted calls and social behavior, we developed a hierarchical observation process within the N-mixture model conditioning lion detectability on their group response to call-ins and individual detection probabilities. We estimated 270 lions (95% credible interval = 170–551) using call-ins but were unable to estimate lion abundance from track data. We found a weak negative relationship between predicted track density and predicted lion abundance from the call-in surveys. Luminosity was negatively correlated with individual detection probability during call-in surveys. Lion abundance and track density were influenced by landcover, but direction of the corresponding effects were undetermined. N-mixture models allowed us to incorporate multiple parameters (e.g., landcover, luminosity, observer effect) influencing lion abundance and probability of detection directly into abundance estimates. We suggest that N-mixture models employing a hierarchical observation process can be used to estimate abundance of other social, herding, and grouping species. PMID:27786283

  19. Estimating Lion Abundance using N-mixture Models for Social Species.

    PubMed

    Belant, Jerrold L; Bled, Florent; Wilton, Clay M; Fyumagwa, Robert; Mwampeta, Stanslaus B; Beyer, Dean E

    2016-10-27

    Declining populations of large carnivores worldwide, and the complexities of managing human-carnivore conflicts, require accurate population estimates of large carnivores to promote their long-term persistence through well-informed management We used N-mixture models to estimate lion (Panthera leo) abundance from call-in and track surveys in southeastern Serengeti National Park, Tanzania. Because of potential habituation to broadcasted calls and social behavior, we developed a hierarchical observation process within the N-mixture model conditioning lion detectability on their group response to call-ins and individual detection probabilities. We estimated 270 lions (95% credible interval = 170-551) using call-ins but were unable to estimate lion abundance from track data. We found a weak negative relationship between predicted track density and predicted lion abundance from the call-in surveys. Luminosity was negatively correlated with individual detection probability during call-in surveys. Lion abundance and track density were influenced by landcover, but direction of the corresponding effects were undetermined. N-mixture models allowed us to incorporate multiple parameters (e.g., landcover, luminosity, observer effect) influencing lion abundance and probability of detection directly into abundance estimates. We suggest that N-mixture models employing a hierarchical observation process can be used to estimate abundance of other social, herding, and grouping species.

  20. The Distribution and Abundance of Bird Species: Towards a Satellite, Data Driven Avian Energetics and Species Richness Model

    NASA Technical Reports Server (NTRS)

    Smith, James A.

    2003-01-01

    This paper addresses the fundamental question of why birds occur where and when they do, i.e., what are the causative factors that determine the spatio-temporal distributions, abundance, or richness of bird species? In this paper we outline the first steps toward building a satellite, data-driven model of avian energetics and species richness based on individual bird physiology, morphology, and interaction with the spatio-temporal habitat. To evaluate our model, we will use the North American Breeding Bird Survey and Christmas Bird Count data for species richness, wintering and breeding range. Long term and current satellite data series include AVHRR, Landsat, and MODIS.

  1. Landscape and Local Correlates of Bee Abundance and Species Richness in Urban Gardens.

    PubMed

    Quistberg, Robyn D; Bichier, Peter; Philpott, Stacy M

    2016-03-31

    Urban gardens may preserve biodiversity as urban population densities increase, but this strongly depends on the characteristics of the gardens and the landscapes in which they are embedded. We investigated whether local and landscape characteristics are important correlates of bee (Hymenoptera: Apiformes) abundance and species richness in urban community gardens. We worked in 19 gardens in the California central coast and sampled bees with aerial nets and pan traps. We measured local characteristics (i.e., vegetation and ground cover) and used the USGS National Land Cover Database to classify the landscape surrounding our garden study sites at 2 km scales. We classified bees according to nesting type (i.e., cavity, ground) and body size and determined which local and landscape characteristics correlate with bee community characteristics. We found 55 bee species. One landscape and several local factors correlated with differences in bee abundance and richness for all bees, cavity-nesting bees, ground-nesting bees, and different sized bees. Generally, bees were more abundant and species rich in bigger gardens, in gardens with higher floral abundance, less mulch cover, more bare ground, and with more grass. Medium bees were less abundant in sites surrounded by more medium intensity developed land within 2 km. The fact that local factors were generally more important drivers of bee abundance and richness indicates a potential for gardeners to promote bee conservation by altering local management practices. In particular, increasing floral abundance, decreasing use of mulch, and providing bare ground may promote bees in urban gardens.

  2. Do predators control prey species abundance? An experimental test with brown treesnakes on Guam.

    PubMed

    Campbell, Earl W; Adams, Amy A Yackel; Converse, Sarah J; Fritts, Thomas H; Rodda, Gordon H

    2012-05-01

    The effect of predators on the abundance of prey species is a topic of ongoing debate in ecology; the effect of snake predators on their prey has been less debated, as there exists a general consensus that snakes do not negatively influence the abundance of their prey. However, this viewpoint has not been adequately tested. We quantified the effect of brown treesnake (Boiga irregularis) predation on the abundance and size of lizards on Guam by contrasting lizards in two 1-ha treatment plots of secondary forest from which snakes had been removed and excluded vs. two 1-ha control plots in which snakes were monitored but not removed or excluded. We removed resident snakes from the treatment plots with snake traps and hand capture, and snake immigration into these plots was precluded by electrified snake barriers. Lizards were sampled in all plots quarterly for a year following snake elimination in the treatment plots. Following the completion of this experiment, we used total removal sampling to census lizards on a 100-m2 subsample of each plot. Results of systematic lizard population monitoring before and after snake removal suggest that the abundance of the skink, Carlia ailanpalai, increased substantially and the abundance of two species of gekkonids, Lepidodactylus lugubris and Hemidactylus frenatus, also increased on snake-free plots. No treatment effect was observed for the skink Emoia caeruleocauda. Mean snout-vent length of all lizard species only increased following snake removal in the treatment plots. The general increase in prey density and mean size was unexpected in light of the literature consensus that snakes do not control the abundance of their prey species. Our findings show that, at least where alternate predators are lacking, snakes may indeed affect prey populations.

  3. Do predators control prey species abundance? An experimental test with brown treesnakes on Guam

    USGS Publications Warehouse

    Campbell, Earl W.; Yackel Adams, Amy A.; Converse, Sarah J.; Fritts, Thomas H.; Rodda, Gordon H.

    2012-01-01

    The effect of predators on the abundance of prey species is a topic of ongoing debate in ecology; the effect of snake predators on their prey has been less debated, as there exists a general consensus that snakes do not negatively influence the abundance of their prey. However, this viewpoint has not been adequately tested. We quantified the effect of brown treesnake (Boiga irregularis) predation on the abundance and size of lizards on Guam by contrasting lizards in two 1-ha treatment plots of secondary forest from which snakes had been removed and excluded vs. two 1-ha control plots in which snakes were monitored but not removed or excluded. We removed resident snakes from the treatment plots with snake traps and hand capture, and snake immigration into these plots was precluded by electrified snake barriers. Lizards were sampled in all plots quarterly for a year following snake elimination in the treatment plots. Following the completion of this experiment, we used total removal sampling to census lizards on a 100-m2 subsample of each plot. Results of systematic lizard population monitoring before and after snake removal suggest that the abundance of the skink, Carlia ailanpalai, increased substantially and the abundance of two species of gekkonids, Lepidodactylus lugubris and Hemidactylus frenatus, also increased on snake-free plots. No treatment effect was observed for the skink Emoia caeruleocauda. Mean snout–vent length of all lizard species only increased following snake removal in the treatment plots. The general increase in prey density and mean size was unexpected in light of the literature consensus that snakes do not control the abundance of their prey species. Our findings show that, at least where alternate predators are lacking, snakes may indeed affect prey populations.

  4. Consequences of organic farming and landscape heterogeneity for species richness and abundance of farmland birds.

    PubMed

    Smith, Henrik G; Dänhardt, Juliana; Lindström, Ake; Rundlöf, Maj

    2010-04-01

    It has been suggested that organic farming may benefit farmland biodiversity more in landscapes that have lost a significant part of its former landscape heterogeneity. We tested this hypothesis by comparing bird species richness and abundance during the breeding season in organic and conventional farms, matched to eliminate all differences not directly linked to the farming practice, situated in either homogeneous plains with only a little semi-natural habitat or in heterogeneous farmland landscapes with abundant field borders and semi-natural grasslands. The effect of farm management on species richness interacted with landscape structure, such that there was a positive relationship between organic farming and diversity only in homogeneous landscapes. This pattern was mainly dependent on the species richness of passerine birds, in particular those that were invertebrate feeders. Species richness of non-passerines was positively related to organic farming independent of the landscape context. Bird abundance was positively related to landscape heterogeneity but not to farm management. This was mainly because the abundance of passerines, particularly invertebrate feeders, was positively related to landscape heterogeneity. We suggest that invertebrate feeders particularly benefit from organic farming because of improved foraging conditions through increased invertebrate abundances in otherwise depauperate homogeneous landscapes. Although many seed-eaters also benefit from increased insect abundance, they may also utilize crop seed resources in homogeneous landscapes and conventional farms. The occurrence of an interactive effect of organic farming and landscape heterogeneity on bird diversity will have consequences for the optimal allocation of resources to restore the diversity of farmland birds.

  5. Genotypic evaluation of rickettsial isolates recovered from various species of ticks in Portugal.

    PubMed Central

    Bacellar, F.; Regnery, R. L.; Núncio, M. S.; Filipe, A. R.

    1995-01-01

    Twelve rickettsial isolates, from Rhipicephalus sanguineus, R. turanicus, Dermacentor marginatus and Hyalomma marginatus, were subjected to genotypic analysis. Amplification of specific DNA sequences, restriction endonuclease digestion of amplified DNA products, and gel electrophoresis were used to identify specific DNA fragment-banding patterns. Five patterns were resolved. Four were homologous with those of previously described rickettsial genotypes, R. conorii, R. slovaca, R. rhipicephali and R. massiliae. The fifth pattern differed by only a single altered restriction endonuclease cleavage site. For the first time in Portugal a widely distributed spectrum of spotted fever group rickettsia was found among potential vector species stressing the need to determine their potential for human and domestic animals infection. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:7867736

  6. Control of Hyalomma lusitanicum (Acari: Ixodidade) Ticks Infesting Oryctolagus cuniculus (Lagomorpha: Leporidae) Using the Entomopathogenic Fungus Beauveria bassiana (Hyocreales: Clavicipitaceae) in Field Conditions.

    PubMed

    González, J; Valcárcel, F; Pérez-Sánchez, J L; Tercero-Jaime, J M; Cutuli, M T; Olmeda, A S

    2016-11-01

    Entomopathogenic fungi are widely used to control arthropods not just in agricultural settings but also in Veterinary Medicine and Public Health. These products have been employed to control tick populations and tick-borne diseases. The effectiveness of these control measures not only depends on the fungi, but also on the tick species and environmental conditions. In Mesomediterranean areas, tick species are adapted to extreme climatic conditions and it is therefore especially important to develop suitable tick control strategies. The aim of this study was to evaluate the effectiveness of a new method of tick control which entails the application of a commercial strain of Beauveria bassiana (Balsamo, Vuillemin) on wild rabbit burrows under field conditions. Aqueous solutions of the product were applied using a mist blower sprayer into 1,717 burrows. Two trials were performed, one in spring and the other in summer. The parasitic index (PI) was calculated for 10 rabbits per treatment per time point on day +30, +60, and +90 posttreatment and efficiency was calculated by comparing the PI for ticks in treated and untreated rabbits. A total of 20,234 ixodid ticks were collected. Hyalomma lusitanicum Koch, 1844 was the most abundant tick feeding on rabbits. Treatment significantly reduced the PI in spring (by 78.63% and 63.28% on day +30 and +60, respectively; P < 0.05), but appeared to be less effective in summer, with a marginally significant tick reduction of 35.72% on day +30 (P = 0.05). Results suggest that the efficacy of applications inside burrows could be temperature-dependent and that such applications could be an economic alternative to rabbit tick control during at least two months using a diluted solution of B. bassiana conidia.

  7. Detection of Severe Fever with Thrombocytopenia Syndrome Virus from Wild Animals and Ixodidae Ticks in the Republic of Korea.

    PubMed

    Oh, Sung-Suck; Chae, Jeong-Byoung; Kang, Jun-Gu; Kim, Heung-Chul; Chong, Sung-Tae; Shin, Jeong-Hwa; Hur, Moon-Suk; Suh, Jae-Hwa; Oh, Myoung-Don; Jeong, Soo-Myoung; Shin, Nam-Shik; Choi, Kyoung-Seong; Chae, Joon-Seok

    2016-06-01

    Severe fever with thrombocytopenia syndrome (SFTS) is caused by SFTS virus (SFTSV), a novel bunyavirus reported to be endemic to central-northeastern China, southern Japan, and the Republic of Korea (ROK). To investigate SFTSV infections, we collected serum samples and ticks from wild animals. Using serum samples and ticks, SFTSV-specific genes were amplified by one-step RT-PCR and nested PCR and sequenced. Indirect immunofluorescence assay (IFA) was performed to analyze virus-specific antibody levels in wild animals. Serum samples were collected from a total of 91 animals: 21 Korean water deer (KWD), 3 Siberian roe deer, 5 gorals, 7 raccoon dogs, 54 wild boars (WBs), and 1 carrion crow. The SFTSV infection rate in wild animals was 3.30% (3 of 91 animals: 1 KWD and 2 WBs). The seropositive rate was 6.59% (6 of 91 animals: 5 KWD and 1 WB). A total of 891 ticks (3 species) were collected from 65 wild animals (9 species). Of the attached tick species, Haemaphysalis longicornis (74.86%) was the most abundant, followed by Haemaphysalis flava (20.20%) and Ixodes nipponensis (4.94%). The average minimum infection rate (MIR) of SFTSV in ticks was 4.98%. The MIRs of H. longicornis, H. flava, and I. nipponensis were 4.51%, 2.22%, and 22.73%, respectively. The MIRs of larvae, nymphs, and adult ticks were 0.68%, 6.88%, and 5.53%, respectively. In addition, the MIRs of fed and unfed ticks were 4.67% and 4.96%, respectively. We detected a low SFTSV infection rate in wild animals, no differences in SFTSV infection rate with respect to bloodsucking in ticks, and SFTSV infection for all developmental stages of ticks. This is the first report describing the detection of SFTSV in wild animals in the ROK.

  8. Spatial predictability of juvenile fish species richness and abundance in a coral reef environment

    NASA Astrophysics Data System (ADS)

    Mellin, C.; Andréfouët, S.; Ponton, D.

    2007-12-01

    Juvenile reef fish communities represent an essential component of coral reef ecosystems in the current focus of fish population dynamics and coral reef resilience. Juvenile fish survival depends on habitat characteristics and is, following settlement, the first determinant of the number of individuals within adult populations. The goal of this study was to provide methods for mapping juvenile fish species richness and abundance into spatial domains suitable for micro and meso-scale analysis and management decisions. Generalized Linear Models predicting juvenile fish species richness and abundance were developed according to spatial and temporal environmental variables measured from 10 m up to 10 km in the southwest lagoon of New Caledonia. The statistical model was further spatially generalized using a 1.5-m resolution, independently created, remotely sensed, habitat map. This procedure revealed that : (1) spatial factors at 10 to 100-m scale explained up to 71% of variability in juvenile species richness, (2) a small improvement (75%) was gained when a combination of environmental variables at different spatial and temporal scales was used and (3) the coupling of remotely sensed data, geographical information system tools and point-based ecological data showed that the highest species richness and abundance were predicted along a narrow margin overlapping the coral reef flat and adjacent seagrass beds. Spatially explicit models of species distribution may be relevant for the management of reef communities when strong relationships exist between faunistic and environmental variables and when models are built at appropriate scales.

  9. Abundance of biting midge species (Diptera: Ceratopogonidae, Culicoides spp.) on cattle farms in Korea.

    PubMed

    Oem, Jae-Ku; Chung, Joon-Yee; Kwon, Mee-Soon; Kim, Toh-Kyung; Lee, Tae-Uk; Bae, You-Chan

    2013-01-01

    Culicoides biting midges were collected on three cattle farms weekly using light traps overnight from May to October between 2010 and 2011 in the southern part of Korea. The seasonal and geographical abundance of Culicodes spp. were measured. A total of 16,538 biting midges were collected from 2010 to 2011, including seven species of Culicoides, four of which represented 98.42% of the collected specimens. These four species were Culicodes (C.) punctatus (n = 14,413), C. arakawae (n = 1,120), C. oxystoma (n = 427), and C. maculatus (n = 318). C. punctatus was the predominant species (87.15%).

  10. Ixodid ticks parasitizing wild carnivores in Romania.

    PubMed

    D'Amico, Gianluca; Dumitrache, Mirabela Oana; Matei, Ioana Adriana; Ionică, Angela Monica; Gherman, Călin Mircea; Sándor, Attila David; Modrý, David; Mihalca, Andrei Daniel

    2017-02-01

    In Romania, data regarding hard-tick diversity and tick-host associations in wild carnivores are scarce. We aimed to identify tick species in wild carnivores and to establish reliable data on tick-host associations. The study was conducted in various Romanian localities from all five ecoregions found in the country. Fourteen species of wild carnivores were examined. Immature and adult ticks were collected and identified using the morphological keys. The frequency and mean intensity of tick infestation, overall and differentiated by species, developmental stage and host were calculated. Of 202 wild carnivores, 68 were parasitized by seven tick species (predominantly Ixodes ricinus, I. hexagonus and Dermacentor reticulatus). The mean intensity of tick infestation was similar in males (6.97, BCa 95% CI 5.15-9.88) and females (5.76, BCa 95% CI 4.15-9.17). The highest prevalence of infested animals was recorded in the pannonian and steppic ecoregions, 66.7 and 52.7%, respectively. In the continental ecoregion the prevalence was 26.7%, whereas in the pontic ecoregion it was 28%. The lowest value, 16.7% was recorded in the alpine ecoregion. In total 430 ticks were collected, and 24.8% (n = 50) of the animals were infested with more than one tick species. Fourteen new tick-host associations were recorded. Our results suggest that anthropogenic changes of the environment lead to the diminishing of the boundaries, between wild and domestic animals, increasing the exposure for both animals and humans, to infective agents, including tick-borne pathogens.

  11. Metabolomics of the tick-Borrelia interaction during the nymphal tick blood meal

    PubMed Central

    Hoxmeier, J. Charles; Fleshman, Amy C.; Broeckling, Corey D.; Prenni, Jessica E.; Dolan, Marc C.; Gage, Kenneth L.; Eisen, Lars

    2017-01-01

    The causal agents of Lyme disease in North America, Borrelia burgdorferi and Borrelia mayonii, are transmitted primarily by Ixodes scapularis ticks. Due to their limited metabolic capacity, spirochetes rely on the tick blood meal for nutrients and metabolic intermediates while residing in the tick vector, competing with the tick for nutrients in the blood meal. Metabolomics is an effective methodology to explore dynamics of spirochete survival and multiplication in tick vectors before transmission to a vertebrate host via tick saliva. Using gas chromatography coupled to mass spectrometry, we identified statistically significant differences in the metabolic profile among uninfected I. scapularis nymphal ticks, B. burgdorferi-infected nymphal ticks and B. mayonii-infected nymphal ticks by measuring metabolism every 24 hours over the course of their up to 96 hour blood meals. Specifically, differences in the abundance of purines, amino acids, carbohydrates, and fatty acids during the blood meal among the three groups of nymphal ticks suggest that B. mayonii and B. burgdorferi may have different metabolic capabilities, especially during later stages of nymphal feeding. Understanding mechanisms underlying variable metabolic requirements of different Lyme disease spirochetes within tick vectors could potentially aid development of novel methods to control spirochete transmission. PMID:28287618

  12. Historic Mining and Agriculture as Indicators of Occurrence and Abundance of Widespread Invasive Plant Species.

    PubMed

    Calinger, Kellen; Calhoon, Elisabeth; Chang, Hsiao-Chi; Whitacre, James; Wenzel, John; Comita, Liza; Queenborough, Simon

    2015-01-01

    Anthropogenic disturbances often change ecological communities and provide opportunities for non-native species invasion. Understanding the impacts of disturbances on species invasion is therefore crucial for invasive species management. We used generalized linear mixed effects models to explore the influence of land-use history and distance to roads on the occurrence and abundance of two invasive plant species (Rosa multiflora and Berberis thunbergii) in a 900-ha deciduous forest in the eastern U.S.A., the Powdermill Nature Reserve. Although much of the reserve has been continuously forested since at least 1939, aerial photos revealed a variety of land-uses since then including agriculture, mining, logging, and development. By 2008, both R. multiflora and B. thunbergii were widespread throughout the reserve (occurring in 24% and 13% of 4417 10-m diameter regularly-placed vegetation plots, respectively) with occurrence and abundance of each varying significantly with land-use history. Rosa multiflora was more likely to occur in historically farmed, mined, logged or developed plots than in plots that remained forested, (log odds of 1.8 to 3.0); Berberis thunbergii was more likely to occur in plots with agricultural, mining, or logging history than in plots without disturbance (log odds of 1.4 to 2.1). Mining, logging, and agriculture increased the probability that R. multiflora had >10% cover while only past agriculture was related to cover of B. thunbergii. Proximity to roads was positively correlated with the occurrence of R. multiflora (a 0.26 increase in the log odds for every 1-m closer) but not B. thunbergii, and roads had no impact on the abundance of either species. Our results indicated that a wide variety of disturbances may aid the introduction of invasive species into new habitats, while high-impact disturbances such as agriculture and mining increase the likelihood of high abundance post-introduction.

  13. Helminth parasitism in two closely related South African rodents: abundance, prevalence, species richness and impinging factors.

    PubMed

    Spickett, Andrea; Junker, Kerstin; Krasnov, Boris R; Haukisalmi, Voitto; Matthee, Sonja

    2017-04-01

    We investigated patterns of helminth infection in two closely related rodents (social Rhabdomys pumilio occurring mainly in xeric habitats and solitary R. dilectus occurring mainly in mesic habitats) at 20 localities in different biomes of South Africa and asked if between-species differences were mainly caused by difference in sociality or difference in environmental conditions of their respective habitats. Helminths recovered from the gastrointestinal tract totalled 11 nematode and 5 cestode species from R. pumilio and 19 nematode and 7 cestode species from R. dilectus. In both hosts, mean abundance and prevalence of nematodes were higher compared to cestodes. Cestode infection as well as nematode abundance, species richness or prevalence did not differ between the two rodents. However, incidence of nematode infection was significantly higher in R. dilectus than in R. pumilio. Moreover, nematode numbers and species richness in infracommunities of R. pumilio inhabiting the relatively more xeric Karoo biome were significantly lower than in those inhabiting the relatively less xeric Fynbos biome. Although we could not unequivocally distinguish between effects of host sociality and environmental factors on the number of individuals and species of helminths in the two hosts, differences in the incidence of nematode infection between R. pumilio and R. dilectus as well as differences in the number of nematode individuals and species between R. pumilio from the Fynbos and the Karoo suggested the effect of environmental conditions on helminth infection to be more important than that of sociality.

  14. Species richness and relative species abundance of Nymphalidae (Lepidoptera) in three forests with different perturbations in the North-Central Caribbean of Costa Rica.

    PubMed

    Stephen, Carolyn; Sánchez, Ragde

    2014-09-01

    Measurements of species richness and species abundance can have important implications for regulations and conservation. This study investigated species richness and abundance of butterflies in the family Nymphalidae at undisturbed, and disturbed habitats in Tirimbina Biological Reserve and Nogal Private Reserve, Sarapiquí, Costa Rica. Traps baited with rotten banana were placed in the canopy and the understory of three habitats: within mature forest, at a river/forest border, and at a banana plantation/forest border. In total, 71 species and 487 individuals were caught and identified during May and June 2011 and May 2013. Species richness and species abundance were found to increase significantly at perturbed habitats (p < 0.0001, p < 0.0001, respectively). The edge effect, in which species richness and abundance increase due to greater complementary resources from different habitats, could be one possible explanation for increased species richness and abundance.

  15. Ticks associated with wild mammals in Ghana.

    PubMed

    Ntiamoa-Baidu, Y; Carr-Saunders, C; Matthews, B E; Preston, P M; Walker, A R

    2005-06-01

    The host ranges of a collection of 21 tick species found on wild mammals in the savanna, forests and coastal zone of Ghana suggested that most species were adapted to feeding mainly on host species within a single mammalian order, i.e. on artiodactyls (bovids/suids), carnivores, rodents or pholidotes (pangolins). Only a few species were dispersed evenly across a range of orders. Seven out of ten of the most common ticks on forest mammals were significantly associated with a particular host species or a group of closely related host species, which could be viewed as their major host or hosts, but they were also recorded much less frequently on a wide range of host species. Two other species were confined to their major hosts. Only one species appeared to be widely dispersed on forest mammals and to lack a particular major host. The majority of tick species therefore occurred on hosts with very distinctive biological, behavioural and ecological characteristics. The study provided no evidence to support the view that host specificity is an artefact of sampling. Finding that the tick species on Ghanaian wild mammals occurred on particular hosts, as well as in distinct habitats, indicated that tick-host associations are important for tick survival and confirmed the importance of climate and vegetation in tick distribution.

  16. Daytime warming lowers community temporal stability by reducing the abundance of dominant, stable species.

    PubMed

    Yang, Zhongling; Zhang, Qian; Su, Fanglong; Zhang, Chunhui; Pu, Zhichao; Xia, Jianyang; Wan, Shiqiang; Jiang, Lin

    2017-01-01

    Daytime warming and nighttime warming have the potential to influence plant community structure and ecosystem functions. However, their impacts on ecological stability remain largely unexplored. We conducted an eight-year field experiment to compare the effects of daytime and nighttime warming on the temporal stability of a temperate steppe in northern China. Our results showed that the cover and stability of dominant species, stability of subordinate species, and compensatory dynamics among species strongly influenced community-level stability. However, daytime, but not nighttime, warming significantly reduced community temporal stability mainly through the reduction in the abundance of dominant, stable species. These findings demonstrate the differential effects of daytime and nighttime warming on community stability and emphasize the importance of understanding the changes of dominant species for accurately predicting community dynamics under climate warming.

  17. Ticks and Tickborne Diseases Affecting Military Personnel

    DTIC Science & Technology

    1989-09-01

    by disease transmission. Various bacteria , rickettsiae , viruses, and protozoans are transmitted to people via tick bites (see Chapter 4). Relatively...Ticks may harbor and transmit to people various disease agents such as protozoa, viruses, bacteria , rickettsiae , and toxins. Several factors are...Natural history. The causative agent of RMSF, Rickettsia rickettsii , is transmitted to man by several species of ticks. In the U.S., 2 of the most

  18. Rich and rare—First insights into species diversity and abundance of Antarctic abyssal Gastropoda (Mollusca)

    NASA Astrophysics Data System (ADS)

    Schwabe, Enrico; Michael Bohn, Jens; Engl, Winfried; Linse, Katrin; Schrödl, Michael

    2007-08-01

    , and all these 84 species seem endemic to Antarctica south of the Polar Front. Comparing diversity and abundances based on epibenthic sledge samples, there is no clear relationship between Antarctic deep-sea gastropod abundance and species richness with depth. However, both Antarctic and adjacent deep-sea areas are still far from being adequately sampled to allow more comprehensive conclusions.

  19. Prevalence of avian haemosporidian parasites is positively related to the abundance of host species at multiple sites within a region.

    PubMed

    Ellis, Vincenzo A; Medeiros, Matthew C I; Collins, Michael D; Sari, Eloisa H R; Coffey, Elyse D; Dickerson, Rebecca C; Lugarini, Camile; Stratford, Jeffrey A; Henry, Donata R; Merrill, Loren; Matthews, Alix E; Hanson, Alison A; Roberts, Jackson R; Joyce, Michael; Kunkel, Melanie R; Ricklefs, Robert E

    2017-01-01

    Parasite prevalence is thought to be positively related to host population density owing to enhanced contagion. However, the relationship between prevalence and local abundance of multiple host species is underexplored. We surveyed birds and their haemosporidian parasites (genera Plasmodium and Haemoproteus) at multiple sites across eastern North America to test whether the prevalence of these parasites in a host species at a particular site is related to that host's local abundance. Prevalence was positively related to host abundance within most sites, although the effect was stronger and more consistent for Plasmodium than for Haemoproteus. In contrast, prevalence was not related to variation in the abundance of most individual host species among sites across the region. These results suggest that parasite prevalence partly reflects the relative abundances of host species in local assemblages. However, three nonnative host species had low prevalence despite being relatively abundant at one site, as predicted by the enemy release hypothesis.

  20. Tick-borne rickettsial pathogens in questing ticks, removed from humans and animals in Mexico

    PubMed Central

    Vargas-Sandoval, Margarita; Torres, Javier

    2016-01-01

    Tick-borne rickettsial diseases (TBRD) are commonly encountered in medical and veterinary clinical settings. The control of these diseases is difficult, requiring disruption of a complex transmission chain involving a vertebrate host and ticks. The geographical distribution of the diseases is related to distribution of the vector, which is an indicator of risk for the population. A total of 1,107 ticks were collected by tick dragging from forests, ecotourism parks and hosts at 101 sites in 22 of the 32 states of Mexico. Collected ticks were placed in 1.5 mL cryovials containing 70% ethanol and were identified to species. Ticks were pooled according to location/host of collection, date of collection, sex, and stage of development. A total of 51 ticks were assayed by polymerase chain reaction (PCR) to confirm species identification using morphological methods. A total of 477 pools of ticks were assayed using PCR techniques for selected tick-borne pathogens. Anaplasma phagocytophilum was the most commonly detected pathogen (45 pools), followed by, Ehrlichia (E.) canis (42), Rickettsia (R.) rickettsii (11), E. chaffeensis (8), and R. amblyommii (1). Rhipicephalus sanguineus was the tick most frequently positive for selected pathogens. Overall, our results indicate that potential tick vectors positive for rickettsial pathogens are distributed throughout the area surveyed in Mexico. PMID:26726019

  1. Molecular investigation of tick-borne pathogens in ticks from grazing cattle in Korea.

    PubMed

    Kang, Seung Won; Doan, Huong Thi Thanh; Choe, Se Eun; Noh, Jin Hyeong; Yoo, Mi Sun; Reddy, Kondreddy Eswar; Kim, Young Ha; Kweon, Chang Hee; Jung, Suk Chan; Chang, Ki Yoon

    2013-06-01

    This study was carried out to identify the tick species that infest grazing cattle and to determine the presence of tick-borne pathogens transmitted by these ticks in Korea. A total of 903 ticks (categorized into 566 tick pools) were collected from five provinces during 2010-2011. The most prevalent tick species was Haemaphysalis longicornis, followed by three Ixodes spp. ticks. The collected ticks were infected with both rickettsial and protozoan pathogens. In all, 469 (82.9%) tick pools tested positive for the Anaplasma/Ehrlichia 16S rRNA gene, whereas 67 (11.8%) were positive for the Babesia/Theileria 18S rRNA gene. Among the rickettsial pathogens, E. canis was detected with the highest rate (22.3%), followed by A. platys (20%), E. chaffeensis (19.4%), E. ewingii (19.3%), Rickettsia sp. (12.4%), A. phagocytophilum (5.5%) and E. muris (0.5%). Among the protozoan pathogens, T. equi was detected with the highest rate (7.2%), followed by T. sergenti/T. buffeli (3.7%) and B. caballi (0.35%). Simultaneous infections with up to seven pathogens were also identified. In particular, ticks infected with rickettsial pathogens were also infected with protozoan pathogens (22 samples). All five provinces investigated infected with tick-borne pathogens.

  2. Species Abundance Distribution of Ectoparasites on Norway Rats (Rattus norvegicus) from a Localized Area in Southwest China

    PubMed Central

    Guo, Xian Guo; Dong, Wen Ge; Men, Xing Yuan; Qian, Ti Jun; Wu, Dian; Ren, Tian Guang; Qin, Feng; Song, Wen Yu; Yang, Zhi Hua; Fletcher, Quinn E

    2016-01-01

    Background: The species of ectoparasites that live on a specific host in a geographical region form an ectoparasite community. Species abundance distributions describe the number of individuals observed for each different species that is encountered within a community. Based on properties of the species abundance distribution, the expected total number of species present in the community can be estimated. Methods: Preston’s lognormal distribution model was used to fit the expected species abundance distribution curve. Using the expected species abundance distribution curve, we estimated the total number of expected parasite species present and the amount of species that were likely missed by our sampling in the field. Results: In total, 8040 ectoparasites (fleas, sucking lice, gamasid mites and chigger mites) were collected from 431 Norway rats (Rattus norvegicus) from a localized area in southwest China. These ectoparasites were identified to be 47 species from 26 genera in 10 families. The majority of ectoparasite species were chigger mites (family Trombiculidae) while the majority of individuals were sucking lice in the family Polyplacidae. The expected species abundance distribution curve demonstrated the classic pattern that the majority of ectoparasite species were rare and that there were a few common species. The total expected number of ectoparasite species on R. norvegicus was estimated to be 85 species, and 38 species were likely missed by our sampling in the field. Conclusions: Norway rats harbor a large suite of ectoparasites. Future field investigations should sample large numbers of host individuals to assess ectoparasite populations. PMID:27308277

  3. Estimating species – area relationships by modeling abundance and frequency subject to incomplete sampling

    USGS Publications Warehouse

    Yamaura, Yuichi; Connor, Edward F.; Royle, Andy; Itoh, Katsuo; Sato, Kiyoshi; Taki, Hisatomo; Mishima, Yoshio

    2016-01-01

    Models and data used to describe species–area relationships confound sampling with ecological process as they fail to acknowledge that estimates of species richness arise due to sampling. This compromises our ability to make ecological inferences from and about species–area relationships. We develop and illustrate hierarchical community models of abundance and frequency to estimate species richness. The models we propose separate sampling from ecological processes by explicitly accounting for the fact that sampled patches are seldom completely covered by sampling plots and that individuals present in the sampling plots are imperfectly detected. We propose a multispecies abundance model in which community assembly is treated as the summation of an ensemble of species-level Poisson processes and estimate patch-level species richness as a derived parameter. We use sampling process models appropriate for specific survey methods. We propose a multispecies frequency model that treats the number of plots in which a species occurs as a binomial process. We illustrate these models using data collected in surveys of early-successional bird species and plants in young forest plantation patches. Results indicate that only mature forest plant species deviated from the constant density hypothesis, but the null model suggested that the deviations were too small to alter the form of species–area relationships. Nevertheless, results from simulations clearly show that the aggregate pattern of individual species density–area relationships and occurrence probability–area relationships can alter the form of species–area relationships. The plant community model estimated that only half of the species present in the regional species pool were encountered during the survey. The modeling framework we propose explicitly accounts for sampling processes so that ecological processes can be examined free of sampling artefacts. Our modeling approach is extensible and could be applied

  4. Abundance, species composition of microzooplankton from the coastal waters of Port Blair, South Andaman Island

    PubMed Central

    2012-01-01

    Background Microzooplankton consisting of protists and metazoa <200 μm. It displays unique feeding mechanisms and behaviours that allow them to graze cells up to five times their own volume. They can grow at rates which equal or exceed prey growth and can serve as a viable food source for metazoans. Moreover, they are individually inconspicuous, their recognition as significant consumers of oceanic primary production. The microzooplankton can be the dominant consumers of phytoplankton production in both oligo- and eutrophic regions of the ocean and are capable of consuming >100% of primary production. Results The microzooplankton of the South Andaman Sea were investigated during September 2011 to January 2012. A total of 44 species belong to 19 genera were recorded in this study. Tintinnids made larger contribution to the total abundance (34%) followed in order by dinoflagellates (24%), ciliates (20%) and copepod nauplii (18%). Foraminifera were numerically less (4%). Tintinnids were represented by 20 species belong to 13 genera, Heterotrophic dinoflagellates were represented by 17 species belong to 3 genera and Ciliates comprised 5 species belong to 3 genera. Eutintinus tineus, Tintinnopsis cylindrical, T. incertum, Protoperidinium divergens, Lomaniella oviformes, Strombidium minimum were the most prevalent microzooplankton. Standing stock of tintinnids ranged from 30–80 cells.L-1 and showed a reverse distribution with the distribution of chlorophyll a relatively higher species diversity and equitability was found in polluted harbour areas. Conclusions The change of environmental variability affects the species composition and abundance of microzooplankton varied spatially and temporarily. The observations clearly demonstrated that the harbor area differed considerably from other area in terms of species present and phytoplankton biomass. Further, the phytoplankton abundance is showed to be strongly influenced by tintinnid with respect to the relationship of

  5. Abundance and phenology patterns of two pond-breeding salamanders determine species interactions in natural populations.

    PubMed

    Anderson, Thomas L; Hocking, Daniel J; Conner, Christopher A; Earl, Julia E; Harper, Elizabeth B; Osbourn, Michael S; Peterman, William E; Rittenhouse, Tracy A G; Semlitsch, Raymond D

    2015-03-01

    Phenology often determines the outcome of interspecific interactions, where early-arriving species often dominate interactions over those arriving later. The effects of phenology on species interactions are especially pronounced in aquatic systems, but the evidence is largely derived from experimental studies. We examined whether differences in breeding phenology between two pond-breeding salamanders (Ambystoma annulatum and A. maculatum) affected metamorph recruitment and demographic traits within natural populations, with the expectation that the fall-breeding A. annulatum would negatively affect the spring-breeding A. maculatum. We monitored populations of each species at five ponds over 4 years using drift fences. Metamorph abundance and survival of A. annulatum were affected by intra- and interspecific processes, whereas metamorph size and date of emigration were primarily influenced by intraspecific effects. Metamorph abundance, snout-vent length, date of emigration and survival for A. maculatum were all predicted by combinations of intra- and interspecific effects, but often showed negative relationships with A. annulatum metamorph traits and abundance. Size and date of metamorphosis were strongly correlated within each species, but in opposite patterns (negative for A. annulatum and positive for A. maculatum), suggesting that the two species use alternative strategies to enhance terrestrial survival and that these factors may influence their interactions. Our results match predictions from experimental studies that suggest recruitment is influenced by intra- and interspecific processes which are determined by phenological differences between species. Incorporating spatiotemporal variability when modeling population dynamics is necessary to understand the importance of phenology in species interactions, especially as shifts in phenology occur under climate change.

  6. Negative plant-soil feedback predicts tree-species relative abundance in a tropical forest.

    PubMed

    Mangan, Scott A; Schnitzer, Stefan A; Herre, Edward A; Mack, Keenan M L; Valencia, Mariana C; Sanchez, Evelyn I; Bever, James D

    2010-08-05

    The accumulation of species-specific enemies around adults is hypothesized to maintain plant diversity by limiting the recruitment of conspecific seedlings relative to heterospecific seedlings. Although previous studies in forested ecosystems have documented patterns consistent with the process of negative feedback, these studies are unable to address which classes of enemies (for example, pathogens, invertebrates, mammals) exhibit species-specific effects strong enough to generate negative feedback, and whether negative feedback at the level of the individual tree is sufficient to influence community-wide forest composition. Here we use fully reciprocal shade-house and field experiments to test whether the performance of conspecific tree seedlings (relative to heterospecific seedlings) is reduced when grown in the presence of enemies associated with adult trees. Both experiments provide strong evidence for negative plant-soil feedback mediated by soil biota. In contrast, above-ground enemies (mammals, foliar herbivores and foliar pathogens) contributed little to negative feedback observed in the field. In both experiments, we found that tree species that showed stronger negative feedback were less common as adults in the forest community, indicating that susceptibility to soil biota may determine species relative abundance in these tropical forests. Finally, our simulation models confirm that the strength of local negative feedback that we measured is sufficient to produce the observed community-wide patterns in tree-species relative abundance. Our findings indicate that plant-soil feedback is an important mechanism that can maintain species diversity and explain patterns of tree-species relative abundance in tropical forests.

  7. Altitudinal and seasonal differences of tick communities in dogs from pastoralist tribes of Northern Kenya.

    PubMed

    D'Amico, Gianluca; Dumitrache, Mirabela O; Široký, Pavel; Albrechtová, Kateřina; Sloboda, Michal; Domşa, Cristian; Sándor, Attila D; Balázsi, Robert; Kanyari, Paul W N; Modrý, David; Mihalca, Andrei D

    2015-09-15

    Studies regarding the distribution and ecology of ticks in dogs from Eastern Africa are scarce. Our research was based on a long-term screening of ticks parasitising the domestic dogs living with indigenous people around Lake Turkana, Mt. Kulal and Mt. Nyiru areas, Northern Kenya. A total of 9977 ticks were collected from 1464 dogs of all ages and both sexes. Identification was performed using morphological keys and data were analyzed using the Repeated Measures ANOVA, post-hoc Scheffe test and F test, relating independent variables as seasons and regions. Final results were translated to maps using GIS software. Five species of ticks were identified: Rhipicephalus pulchellus, Rhipicephalus sanguineus sensu lato (s.l.), Rhipicephalus armatus, Amblyomma gemma and Hyalomma truncatum. Our results suggest a statistical difference of the tick community structure related to seasonal and altitudinal distribution. Parasitism with R. armatus and R. pulchellus was higher in September-October than in January, whereas, R. sanguineus s.l. was not influenced by the season. Rhipicephalus armatus was present exclusively on dogs living in semi-desert areas, while R. sanguineus s.l. was the dominant species present on the shores of Lake Turkana. Although R. pulchellus was present in the all studied areas, this species had a significantly higher abundance in the afromontane region of Mt. Kulal and montane xeromorphic forest of Mt. Nyiru; these regions are characterized by elevated humidity and cooler climate. Similar geo-climatic distribution is typical also for A. gemma, which was found in dogs exclusively in Mt. Kulal afromontane area. The current work represents the most extensive study performed on the tick community structure of dogs in Eastern Africa. The results showed a relatively limited tick species diversity, with clear seasonal differences and altitudinal distribution.

  8. Molecular detection of tick-borne pathogens in Ixodes ricinus from Moldova collected in 1960.

    PubMed

    Movila, Alexandru; Toderas, Ion; Uspenskaia, Inga; Conovalov, Jurii

    2013-06-01

    This study is the first report about the prevalence of tick-borne pathogens, as well as their (co-)infection rates, in the museum-archived I. ricinus female ticks collected in Moldova in 1960. A total of 16.7% (21/126) ticks was mono-infected. Borrelia burgdorferi sensu stricto was revealed as the most abundant species (4.8%) followed by B. garinii (1.6%), B. afzelii (0.8%), B. valaisiana (0.8%), and B. lusitaniae (0.8%). DNA of Rickettsia helvetica (2.4%), R. monacensis (2.4%), Anaplasma phagocytophilum (2.4%), 'Candidatus Neoehrlichia mikurensis' (0.8%), and Babesia microti (0.8%) were also detected, indicating the occurrence of these emerging tick-borne microorganisms in Moldova since 1960 at least. In this study, we detected a co-infection (0.8%; 1/126 tested ticks) between B. microti and R. helvetica. Additional investigations are warranted to further characterize a historical snapshot of the distribution of tick-borne pathogens in Europe.

  9. Different lines of evidence used to delimit species in ticks: A study of the South American populations of Amblyomma parvum (Acari: Ixodidae).

    PubMed

    Nava, Santiago; Gerardi, Monize; Szabó, Matias P J; Mastropaolo, Mariano; Martins, Thiago F; Labruna, Marcelo B; Beati, Lorenza; Estrada-Peña, Agustín; Guglielmone, Alberto A

    2016-10-01

    The goal of this work was to combine different lines of evidence besides that of molecular markers to delimit species in ticks when the molecular data are not totally congruent. Two groups (Argentina, Brazil) of South American populations of Amblyomma parvum were compared to test whether the splitting of these two lineages suggested by genetic analyses is complete. Comparative studies of reproductive compatibility, morphological analyses of fixed characters, and comparison of population distributions in spatially defined ecological niches were performed.The morphological comparisons of both discrete and morphometric characters showed no differences among A. parvum ticks from Argentina and Brazil. The intercrosses and backcrosses showed evidence of pre- and post-zygotic compatibility between the two groups. No significant differences in environmental traits were found which would justify the separation of the records of A. parvum in distinct groups. Although the gene flow between the two groups of populations is limited, the absence of reproductive barriers, the lack of significant morphological differences, and the absence of significant differences in the niche preferences indicate that populations of A. parvum from Argentina and Brazil should be treated as a single species. The speciation conjectures suggested by some analyses of mitochondrial DNA sequences were not supported when different lines of evidences were compared.

  10. Estimating forest species abundance through linear unmixing of CHRIS/PROBA imagery

    NASA Astrophysics Data System (ADS)

    Stagakis, Stavros; Vanikiotis, Theofilos; Sykioti, Olga

    2016-09-01

    The advancing technology of hyperspectral remote sensing offers the opportunity of accurate land cover characterization of complex natural environments. In this study, a linear spectral unmixing algorithm that incorporates a novel hierarchical Bayesian approach (BI-ICE) was applied on two spatially and temporally adjacent CHRIS/PROBA images over a forest in North Pindos National Park (Epirus, Greece). The scope is to investigate the potential of this algorithm to discriminate two different forest species (i.e. beech - Fagus sylvatica, pine - Pinus nigra) and produce accurate species-specific abundance maps. The unmixing results were evaluated in uniformly distributed plots across the test site using measured fractions of each species derived by very high resolution aerial orthophotos. Landsat-8 images were also used to produce a conventional discrete-type classification map of the test site. This map was used to define the exact borders of the test site and compare the thematic information of the two mapping approaches (discrete vs abundance mapping). The required ground truth information, regarding training and validation of the applied mapping methodologies, was collected during a field campaign across the study site. Abundance estimates reached very good overall accuracy (R2 = 0.98, RMSE = 0.06). The most significant source of error in our results was due to the shadowing effects that were very intense in some areas of the test site due to the low solar elevation during CHRIS acquisitions. It is also demonstrated that the two mapping approaches are in accordance across pure and dense forest areas, but the conventional classification map fails to describe the natural spatial gradients of each species and the actual species mixture across the test site. Overall, the BI-ICE algorithm presented increased potential to unmix challenging objects with high spectral similarity, such as different vegetation species, under real and not optimum acquisition conditions. Its

  11. Attachment site selection of ticks on roe deer, Capreolus capreolus.

    PubMed

    Kiffner, C; Lödige, C; Alings, M; Vor, T; Rühe, F

    2011-01-01

    The spatio-temporal attachment site patterns of ticks feeding on their hosts can be of significance if co-feeding transmission (i.e. from tick to tick without a systemic infection of the host) of pathogens affects the persistence of a given disease. Using tick infestation data on roe deer, we analysed preferred attachment sites and niche width of Ixodes ticks (larvae, nymphs, males, females) and investigated the degree of inter- and intrastadial aggregation. The different development stages showed rather consistent attachment site patterns and relative narrow feeding site niches. Larvae were mostly found on the head and on the front legs of roe deer, nymphs reached highest densities on the head and highest adult densities were found on the neck of roe deer. The tick stages feeding (larvae, nymphs, females) on roe deer showed high degrees of intrastadial spatial aggregation, whereas males did not. Male ticks showed large feeding site overlap with female ticks. Feeding site overlap between larval-female and larval-nymphal ticks did occur especially during the months May-August on the head and front legs of roe deer and might allow pathogen transmission via co-feeding. Tick density, niche width and niche overlap on roe deer are mainly affected by seasonality, reflecting seasonal activity and abundance patterns of ticks. Since different tick development stages occur spatially and temporally clustered on roe deer, transmission experiments of tick-borne pathogens are urgently needed.

  12. Plankton studies in San Francisco Bay; II, Phytoplankton abundance and species composition, July 1977-December 1979

    USGS Publications Warehouse

    Wong, Raymond L. J.; Cloern, James E.

    1981-01-01

    Data are presented on the phytoplankton species composition and abundance in San Francisco Bay from July 1977 through December 1979. Phytoplankton identification and enumerations were made at selected stations. Sample collections were made at selected stations in the main channel of the Bay from Rio Vista on the Sacramento River to Calaveras Point in South San Francisco Bay, and at shoal stations in the central portion of South San Francisco Bay, San Pablo Bay, and Suisun Bay. Also reported, from October 1978 through December 1979, are the calculated phytoplankton carbon and percent nondiatom carbon, and the species list. This study is one component of an ongoing interdisciplinary study of San Francisco Bay. (USGS)

  13. Research on the ecology of ticks and tick-borne pathogens—methodological principles and caveats

    PubMed Central

    Estrada-Peña, Agustín; Gray, Jeremy S.; Kahl, Olaf; Lane, Robert S.; Nijhof, Ard M.

    2013-01-01

    Interest in tick-transmitted pathogens has experienced an upsurge in the past few decades. Routine application of tools for the detection of fragments of foreign DNA in ticks, together with a high degree of interest in the quantification of disease risk for humans, has led to a marked increase in the number of reports on the eco-epidemiology of tick-borne diseases. However, procedural errors continue to accumulate in the scientific literature, resulting in misleading information. For example, unreliable identification of ticks and pathogens, erroneous interpretations of short-term field studies, and the hasty acceptance of some tick species as vectors have led to ambiguities regarding the vector role of these arthropods. In this review, we focus on the ecological features driving the life cycle of ticks and the resulting effects on the eco-epidemiology of tick-transmitted pathogens. We review the factors affecting field collections of ticks, and we describe the biologically and ecologically appropriate procedures for describing tick host-seeking activity and its correlation with environmental traits. We detail the climatic variables that have biological importance on ticks and explain how they should be properly measured and analyzed. We also provide evidence to critically reject the use of some environmental traits that are being increasingly reported as the drivers of the behavior of ticks. With the aim of standardization, we propose unambiguous definitions of the status of hosts and ticks regarding their ability to maintain and spread a given pathogen. We also describe laboratory procedures and standards for evaluating the vectorial capacity of a tick or the reservoir role of a host. This approach should provide a coherent framework for the reporting of research findings concerning ticks and tick-borne diseases. PMID:23964348

  14. Research on the ecology of ticks and tick-borne pathogens--methodological principles and caveats.

    PubMed

    Estrada-Peña, Agustín; Gray, Jeremy S; Kahl, Olaf; Lane, Robert S; Nijhof, Ard M

    2013-01-01

    Interest in tick-transmitted pathogens has experienced an upsurge in the past few decades. Routine application of tools for the detection of fragments of foreign DNA in ticks, together with a high degree of interest in the quantification of disease risk for humans, has led to a marked increase in the number of reports on the eco-epidemiology of tick-borne diseases. However, procedural errors continue to accumulate in the scientific literature, resulting in misleading information. For example, unreliable identification of ticks and pathogens, erroneous interpretations of short-term field studies, and the hasty acceptance of some tick species as vectors have led to ambiguities regarding the vector role of these arthropods. In this review, we focus on the ecological features driving the life cycle of ticks and the resulting effects on the eco-epidemiology of tick-transmitted pathogens. We review the factors affecting field collections of ticks, and we describe the biologically and ecologically appropriate procedures for describing tick host-seeking activity and its correlation with environmental traits. We detail the climatic variables that have biological importance on ticks and explain how they should be properly measured and analyzed. We also provide evidence to critically reject the use of some environmental traits that are being increasingly reported as the drivers of the behavior of ticks. With the aim of standardization, we propose unambiguous definitions of the status of hosts and ticks regarding their ability to maintain and spread a given pathogen. We also describe laboratory procedures and standards for evaluating the vectorial capacity of a tick or the reservoir role of a host. This approach should provide a coherent framework for the reporting of research findings concerning ticks and tick-borne diseases.

  15. Tick-Borne Relapsing Fever

    MedlinePlus

    ... bite from a tick that carries the bacteria Borrelia hermsii. In the United States, these ticks are ... was contributed by: familydoctor.org editorial staff Tags: borrelia hermsii, illness from ticks, recurring, TBRF, tick, tick ...

  16. Sampling designs matching species biology produce accurate and affordable abundance indices

    PubMed Central

    Farley, Sean; Russell, Gareth J.; Butler, Matthew J.; Selinger, Jeff

    2013-01-01

    Wildlife biologists often use grid-based designs to sample animals and generate abundance estimates. Although sampling in grids is theoretically sound, in application, the method can be logistically difficult and expensive when sampling elusive species inhabiting extensive areas. These factors make it challenging to sample animals and meet the statistical assumption of all individuals having an equal probability of capture. Violating this assumption biases results. Does an alternative exist? Perhaps by sampling only where resources attract animals (i.e., targeted sampling), it would provide accurate abundance estimates more efficiently and affordably. However, biases from this approach would also arise if individuals have an unequal probability of capture, especially if some failed to visit the sampling area. Since most biological programs are resource limited, and acquiring abundance data drives many conservation and management applications, it becomes imperative to identify economical and informative sampling designs. Therefore, we evaluated abundance estimates generated from grid and targeted sampling designs using simulations based on geographic positioning system (GPS) data from 42 Alaskan brown bears (Ursus arctos). Migratory salmon drew brown bears from the wider landscape, concentrating them at anadromous streams. This provided a scenario for testing the targeted approach. Grid and targeted sampling varied by trap amount, location (traps placed randomly, systematically or by expert opinion), and traps stationary or moved between capture sessions. We began by identifying when to sample, and if bears had equal probability of capture. We compared abundance estimates against seven criteria: bias, precision, accuracy, effort, plus encounter rates, and probabilities of capture and recapture. One grid (49 km2 cells) and one targeted configuration provided the most accurate results. Both placed traps by expert opinion and moved traps between capture sessions, which

  17. Hard ticks (Acari, Ixodidae) of Croatia

    PubMed Central

    Krčmar, Stjepan

    2012-01-01

    Abstract The present paper is based on original and literature data. In Croatia the first studies on the occurrence of ixodid species were made about 80 years ago. The number of tick species recorded in Croatia considerably increased during the 1950s, 60s, 70s and 80s of the past century. A total of 21 species of hard tick belonging to 5 genera have been recorded in Croatia. Ixodes is the best represented genus, with seven species recorded. Haemaphysalis is represented by six species, followed by Rhipicephalus with four species. Dermacentor and Hyalomma are represented by two species each. The ticks were collected on 47 different host species. Eleven tick species were collected on Bos taurus and Ovis aries, followed by Capra hircus and Equus caballus with 8 species and Canis lupus familiaris with 6 species. On the remaining 42 host species one, two or three tick species were collected. The most widespread tick is Ixodes ricinus which was found on 25 different host species. PMID:23372407

  18. Predicting probability of occurrence and factors affecting distribution and abundance of three Ozark endemic crayfish species at multiple spatial scales

    USGS Publications Warehouse

    Nolen, Matthew S.; Magoulick, Daniel D.; DiStefano, Robert J.; Imhoff, Emily M.; Wagner, Brian K.

    2014-01-01

    We found that a range of environmental variables were important in predicting crayfish distribution and abundance at multiple spatial scales and their importance was species-, response variable- and scale dependent. We would encourage others to examine the influence of spatial scale on species distribution and abundance patterns.

  19. Tick Bites (For Parents)

    MedlinePlus

    ... medical treatment, some ticks (like the deer tick, wood tick, and others) can carry harmful germs and ... with at least 10% to 30% DEET for protection against bites and stings in kids older than ...

  20. Shifts in Campylobacter species abundance may reflect general microbial community shifts in periodontitis progression

    PubMed Central

    Henne, Karsten; Fuchs, Felix; Kruth, Sebastian; Horz, Hans-Peter; Conrads, Georg

    2014-01-01

    Background Oral Campylobacter species have been found to be associated with periodontitis progression. While the etiological significance of Campylobacter rectus is quite established, the association of C. gracilis, C. concisus, and C. curvus with health or disease remains contradictory. Objectives This study hypothesizes that the proportion of species within the Campylobacter genus rather than the absolute abundance of a single species is a suitable indicator for periodontitis progression. Design Subgingival plaque from 90 periodontitis patients and gingival sulcus fluid of 32 healthy individuals were subjected to a newly developed nested PCR approach, in which all Campylobacter spp. were amplified simultaneously. The resulting mixture of 16S-rRNA-gene-amplicons were separated by single-stranded conformation polymorphism (SSCP) gel electrophoresis, followed by sequencing and identification of excised bands and relative quantification of band intensities. In all samples, the abundance of selected periodontitis marker species was determined based on DNA hybridization on a microarray. Results The highly prevalent Campylobacter community was composed of varying proportions of C. rectus, C. gracilis, C. concisus, and C. curvus. Cluster analysis based on SSCP-banding pattern resulted in distinct groups which in turn coincided with significant differences in abundance of established periodontitis marker species (Tannerella forsythia, Porphyromonas gingivalis, and Fusobacterium nucleatum) and progression. Conclusions The shift in the Campylobacter community composition seems to display the general microbial community shift during clinical progression in a simplified manner. The focus on members of the Campylobacter in this study suggests that this genus can be an indicator of ecological changes in the subgingival oral microflora. PMID:25412608

  1. Problem of ticks and tick-borne diseases in India with special emphasis on progress in tick control research: a review.

    PubMed

    Ghosh, Srikant; Nagar, Gaurav

    2014-12-01

    Ticks, as vectors of several zoonotic diseases, are ranked second only to mosquitoes as vectors. The diseases spread by ticks are a major constraint to animal productivity while causing morbidity and mortality in both animals and humans. A number of tick species have been recognised since long as vectors of lethal pathogens, viz. Crimean-Congo haemorrhagic fever virus (CCHFV), Kyasanur forest disease virus (KFDV), Babesia spp, Theileria, Rickettsia conorii, Anaplasma marginale, etc. and the damages caused by them are well-recognised. There is a need to reassess the renewed threat posed by the tick vectors and to prioritize the tick control research programme. This review is focused on the major tick-borne human and animal diseases in India and the progress in vector control research with emphasis on acaricide resistance, tick vaccine and the development of potential phytoacaricides as an integral part of integrated tick control programme.

  2. Mosquito species succession and physicochemical factors affecting their abundance in rice fields in Mwea, Kenya.

    PubMed

    Muturi, Ephantus J; Mwangangi, Joseph; Shililu, Josephat; Muriu, Simon; Jacob, Benjamin; Kabiru, Ephantus; Gu, Weidong; Mbogo, Charles; Githure, John; Novak, Robert

    2007-03-01

    The succession of mosquito species and abiotic factors affecting their distribution and abundance in rice (Oryza spp.) fields was investigated over a 16-wk rice growing cycle covering the period between January and May 2006. Fifteen experimental rice plots were sampled for mosquito larvae and characterized based on rice height, number of tillers, floating vegetation cover, water depth, water temperature, turbidity, salinity, pH, dissolved oxygen, total dissolved solids, and conductivity. Microscopic identification of 3,025 larvae yielded nine mosquito species predominated by Anopheles arabiensis Patton (45.0%), Culex quinquefasciatus Say (35.8%), Anopheles pharoensis Theobald (9.0%) and Ficalbia splendens Theobald (7.1%). Other species, including Anopheles rufipes Gough, Anopheles coustani Laveran, Anonopheles maculipalpis Giles, Culex annulioris Theobald, and Culex poicilipes Theobald made up 3.1% of the total collection. Anopheles gambiae s.l., Cx. quinquefasciatus, and An. pharoensis occurred throughout the cycle, but they were more abundant up to 4 wk posttransplanting with peaks after fertilizer application. As rice plants became established, three groups of mosquitoes were recognized: the first groups included An. rufipes, Fl. splendens, and Cx. annulioris, which occurred throughout much of the second half of the rice cycle, whereas the second group included Cx. poicilipes, which was found in the middle of the rice cycle. An. coustani and An. maculipalpis formed the third group occurring toward the end of the cycle. Dissolved oxygen, number of tillers, and rice height were negatively associated with the abundance ofAn. arabiensis and Cx. quinquefasciatus larvae. In addition, Cx. quinquefasciatus also was associated with water depth (-ve) and turbidity (+ve). Abundance of An. pharoensis larvae was significantly associated with water temperature (+ve), the number of tillers (-ve), and rice height (-ve), whereas Fl. splendens was significantly associated with

  3. Ticks associated with domestic dogs and cats in Florida, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Voluntary collections of ticks from domestic dogs and cats by veterinary practitioners across Florida were conducted over a 10 month period. Of the 1,337 ticks submitted, five species of ixodid ticks were identified and included Rhipicephalus sanguineus, Amblyomma americanum, A. maculatum, Dermacen...

  4. Urban Breeding Corvids as Disseminators of Ticks and Emerging Tick-Borne Pathogens.

    PubMed

    Sándor, Attila D; Kalmár, Zsuzsa; Matei, Ioana; Ionică, Angela Monica; Mărcuţan, Ioan-Daniel

    2017-02-01

    Crows (Corvidae) are common city dwellers worldwide and are increasingly important subjects of epidemiology studies. Although their importance as hosts and transmitters of a number of zoonotic parasites and pathogens is well known, there are no studies on their importance as tick hosts. After mosquitoes, ticks are the most important vectors of zoonotic pathogens, especially for those causing emerging zoonotic diseases. Pathogenic bacteria, especially Borrelia spp., Rickettsia spp., and Anaplasma spp., vectored by ticks, are the cause for most vector-borne diseases in Europe. Here we report on ticks and tick-borne pathogens harbored by urban breeding crows. A total of 36 birds (33.33%, n = 108) hosted ticks, with 91 individual ticks belonging to 6 species (Haemaphysalis concinna, Haemaphysalis parva, Haemaphysalis punctata, Hyalomma marginatum, Ixodes arboricola, and Ixodes ricinus). Rickettsia spp. DNA was found in 6.6% of ticks and 1.9% of bird tissues, whereas Anaplasma phagocytophilum was found in 5.9% of ticks and 0.9% of birds. Two rickettsial genospecies were located, Rickettsia helvetica and Rickettsia monacensis. This is the first study to determine such a diverse tick spectrum feeding on urban corvids, while highlighting their importance as tick hosts and raising concerns about their potential risk to human health.

  5. Widespread Rickettsia spp. Infections in Ticks (Acari: Ixodoidea) in Taiwan.

    PubMed

    Kuo, Chi-Chien; Shu, Pei-Yun; Mu, Jung-Jung; Lee, Pei-Lung; Wu, Yin-Wen; Chung, Chien-Kung; Wang, Hsi-Chieh

    2015-09-01

    Ticks are second to mosquitoes as the most important disease vectors, and recent decades have witnessed the emergence of many novel tick-borne rickettsial diseases, but systematic surveys of ticks and tick-borne rickettsioses are generally lacking in Asia. We collected and identified ticks from small mammal hosts between 2006 and 2010 in different parts of Taiwan. Rickettsia spp. infections in ticks were identified by targeting ompB and gltA genes with nested polymerase chain reaction. In total, 2,732 ticks were collected from 1,356 small mammals. Rhipicephalus haemaphysaloides Supino (51.8% of total ticks), Haemaphysalis bandicota Hoogstraal & Kohls (28.0%), and Ixodes granulatus Supino (20.0%) were the most common tick species, and Rattus losea Swinhoe (44.7% of total ticks) and Bandicota indica Bechstein (39.9%) were the primary hosts. The average Rickettsia infective rate in 329 assayed ticks was 31.9% and eight Rickettsia spp. or closely related species were identified. This study shows that rickettsiae-infected ticks are widespread in Taiwan, with a high diversity of Rickettsia spp. circulating in the ticks. Because notifiable rickettsial diseases in Taiwan only include mite-borne scrub typhus and flea-borne murine typhus, more studies are warranted for a better understanding of the real extent of human risks to rickettsioses in Taiwan.

  6. Diatom species abundance and morphologically-based dissolution proxies in coastal Southern Ocean assemblages

    NASA Astrophysics Data System (ADS)

    Warnock, Jonathan P.; Scherer, Reed P.

    2015-07-01

    Taphonomic processes alter diatom assemblages in sediments, thus potentially negatively impacting paleoclimate records at various rates across space, time, and taxa. However, quantitative taphonomic data is rarely included in diatom-based paleoenvironmental reconstructions and no objective standard exists for comparing diatom dissolution in sediments recovered from marine depositional settings, including the Southern Ocean's opal belt. Furthermore, identifying changes to diatom dissolution through time can provide insight into the efficiency of both upper water column nutrient recycling and the biological pump. This is significant in that reactive metal proxies (e.g. Al, Ti) in the sediments only account for post-depositional dissolution, not the water column where the majority of dissolution occurs. In order to assess the range of variability of responses to dissolution in a typical Southern Ocean diatom community and provide a quantitative guideline for assessing taphonomic variability in diatoms recovered from core material, a sediment trap sample was subjected to controlled, serial dissolution. By evaluating dissolution-induced changes to diatom species' relative abundance, three preservational categories of diatoms have been identified: gracile, intermediate, and robust. The relative abundances of these categories can be used to establish a preservation grade for diatom assemblages. However, changes to the relative abundances of diatom species in sediment samples may reflect taphonomic or ecological factors. In order to address this complication, relative abundance changes have been tied to dissolution-induced morphological change to the areolae of Fragilariopsis curta, a significant sea-ice indicator in Southern Ocean sediments. This correlation allows differentiation between gracile species loss to dissolution versus ecological factors or sediment winnowing. These results mirror a similar morphological dissolution index from a parallel study utilizing

  7. Moisture conditions and the presence of bryophytes determine fescue species abundance in a dry calcareous grassland.

    PubMed

    Otsus, Merit; Zobel, Martin

    2004-01-01

    Festuca ovina is the abundant matrix-forming species and F. rubra a subordinate species in shallow-soil calcareous grasslands. F. pratensis is a transient species, occurring sparsely in this community. We hypothesised that the different abundances of these three species are primarily due to the differential effect of moisture conditions on their germination and early establishment, and that the effect of the pattern of rainfall intensity depends on the presence or absence of a bryophyte layer. We studied the dependence of the germination and establishment of the three fescue species on the moisture conditions both in the laboratory and in the patches of intact grassland community (microcosms). In a laboratory germination experiment, F. pratensis showed the highest, F. rubra, the intermediate and F. ovina, the lowest drought tolerance. In microcosms, the establishment of F. ovina was the highest. At the same time, the annual mortality of seedlings of F. ovina was the lowest. All three species responded positively to an increasing irrigation level. Differently from F. ovina, F. rubra showed a positive response only in plots from which the bryophyte layer had been removed, while F. pratensis responded positively to both irrigation and bryophyte removal. We conclude that moisture conditions have a differential effect on the three fescue species mainly in the seedling establishment, not in the germination phase. For the successful establishment of F. rubra and F. pratensis, the coincidence of high rainfall and local disturbance, removing bryophytes, is required. The presence or absence of bryophytes had no effect on establishment in dry years, while in rainy years the removal of bryophytes has a clear positive effect.

  8. The seasonal abundance of phlebotomine sand flies, Lutzomyia species in Florida.

    PubMed

    Mann, Rajinder S; Kaufman, Phillip E

    2010-03-01

    The seasonality of phlebotomine sand flies was studied in Florida, utilizing colored light-emitting diode- and attractant-baited Mosquito Magnet MM-X traps from September 2006 to September 2008 at San Felasco Hammock Preserve State Park, Gainesville, FL. A total of 6,278 sand flies were collected from 314 actual nights and 1,692 total trap-nights, yielding 3.7 sand flies per trap-night. Lutzomyia shannoni was the predominant species, constituting 55% to 80% of the total sand fly populations collected during the studies. Both L. shannoni and L. vexator populations were highly seasonal and were moderately influenced by weather factors. Lutzomyia shannoni populations peaked in May and showed reduced activity during December, January, and February. This species was active throughout the year and showed positive and negative correlations with average monthly temperature and relative humidity, respectively. Lutzomyia vexator showed peak activity during August and October with an activity lull from December to March. This species showed a positive correlation with average monthly temperature. No correlations were observed with either species for average daily, weekly, or 1- to 8-wk-lagging precipitation, number of rainy days, wind speed, or lunar phases. Lutzomyia shannoni abundance was weakly correlated to L. vexator abundance. No other Lutzomyia spp. were collected during the study.

  9. Relative abundance and species richness of cerambycid beetles in partial cut and uncut bottomland hardwood forests

    USGS Publications Warehouse

    Newell, P.; King, S.

    2009-01-01

    Partial cutting techniques are increasingly advocated and used to create habitat for priority wildlife. However, partial cutting may or may not benefit species dependent on deadwood; harvesting can supplement coarse woody debris in the form of logging slash, but standing dead trees may be targeted for removal. We sampled cerambycid beetles during the spring and summer of 2006 and 2007 with canopy malaise traps in 1- and 2-year-old partial cut and uncut bottomland hardwood forests of Louisiana. We captured a total of 4195 cerambycid beetles representing 65 species. Relative abundance was higher in recent partial cuts than in uncut controls and with more dead trees in a plot. Total species richness and species composition were not different between treatments. The results suggest partial cuts with logging slash left on site increase the abundance of cerambycid beetles in the first few years after partial cutting and that both partial cuts and uncut forest should be included in the bottomland hardwood forest landscape.

  10. Parametric scaling from species relative abundances to absolute abundances in the computation of biological diversity: a first proposal using Shannon's entropy.

    PubMed

    Ricotta, Carlo

    2003-01-01

    Traditional diversity measures such as the Shannon entropy are generally computed from the species' relative abundance vector of a given community to the exclusion of species' absolute abundances. In this paper, I first mention some examples where the total information content associated with a given community may be more adequate than Shannon's average information content for a better understanding of ecosystem functioning. Next, I propose a parametric measure of statistical information that contains both Shannon's entropy and total information content as special cases of this more general function.

  11. Abundance and Spatial Dispersion of Rice Stem Borer Species in Kahama, Tanzania.

    PubMed

    Leonard, Alfonce; Rwegasira, Gration M

    2015-01-01

    Species diversity, abundance, and dispersion of rice stem borers in framer's fields were studied in four major rice growing areas of Kahama District. Stem borer larvae were extracted from the damaged tillers in 16 quadrants established in each field. Adult Moths were trapped by light traps and collected in vials for identification. Results indicated the presence of Chilo partellus, Maliarpha separatella, and Sesamia calamistis in all study areas. The most abundant species was C. partellus (48.6%) followed by M. separatella (35.4%) and S. calamistis was least abundant (16.1%). Stem borers dispersion was aggregated along the edges of rice fields in three locations (wards) namely: Bulige, Chela, and Ngaya. The dispersion in the fourth ward, Kashishi was uniform as established from two of the three dispersion indices tested. Further studies would be required to establish the available alternative hosts, the extent of economic losses and the distribution of rice stem borers in the rest of the Lake zone of Tanzania.

  12. Abundance and Spatial Dispersion of Rice Stem Borer Species in Kahama, Tanzania

    PubMed Central

    Leonard, Alfonce; Rwegasira, Gration M.

    2015-01-01

    Species diversity, abundance, and dispersion of rice stem borers in framer’s fields were studied in four major rice growing areas of Kahama District. Stem borer larvae were extracted from the damaged tillers in 16 quadrants established in each field. Adult Moths were trapped by light traps and collected in vials for identification. Results indicated the presence of Chilo partellus, Maliarpha separatella, and Sesamia calamistis in all study areas. The most abundant species was C. partellus (48.6%) followed by M. separatella (35.4%) and S. calamistis was least abundant (16.1%). Stem borers dispersion was aggregated along the edges of rice fields in three locations (wards) namely: Bulige, Chela, and Ngaya. The dispersion in the fourth ward, Kashishi was uniform as established from two of the three dispersion indices tested. Further studies would be required to establish the available alternative hosts, the extent of economic losses and the distribution of rice stem borers in the rest of the Lake zone of Tanzania. PMID:26411785

  13. Bacterial colonization and extinction on marine aggregates: stochastic model of species presence and abundance

    PubMed Central

    Kramer, Andrew M; Lyons, M Maille; Dobbs, Fred C; Drake, John M

    2013-01-01

    Organic aggregates provide a favorable habitat for aquatic microbes, are efficiently filtered by shellfish, and may play a major role in the dynamics of aquatic pathogens. Quantifying this role requires understanding how pathogen abundance in the water and aggregate size interact to determine the presence and abundance of pathogen cells on individual aggregates. We build upon current understanding of the dynamics of bacteria and bacterial grazers on aggregates to develop a model for the dynamics of a bacterial pathogen species. The model accounts for the importance of stochasticity and the balance between colonization and extinction. Simulation results suggest that while colonization increases linearly with background density and aggregate size, extinction rates are expected to be nonlinear on small aggregates in a low background density of the pathogen. Under these conditions, we predict lower probabilities of pathogen presence and reduced abundance on aggregates compared with predictions based solely on colonization. These results suggest that the importance of aggregates to the dynamics of aquatic bacterial pathogens may be dependent on the interaction between aggregate size and background pathogen density, and that these interactions are strongly influenced by ecological interactions and pathogen traits. The model provides testable predictions and can be a useful tool for exploring how species-specific differences in pathogen traits may alter the effect of aggregates on disease transmission. PMID:24340173

  14. Integration of non-indigenous species within the interspecific abundance-occupancy relationship

    NASA Astrophysics Data System (ADS)

    Rigal, François; Whittaker, Robert J.; Triantis, Kostas A.; Borges, Paulo A. V.

    2013-04-01

    There is a broad consensus that habitat disturbance and introduction of non-indigenous species may dramatically modify community structure, particularly in insular ecosystems. However, it is less clear whether emergent macroecological patterns are similarly affected. The positive interspecific abundance-occupancy relationship (IAOR) is one of the most pervasive macroecological patterns, yet has rarely been analyzed for oceanic island assemblages. We use an extensive dataset for arthropods from six islands within the Azorean archipelago to test: (1) whether indigenous and non-indigenous species are distributed differently within the IAOR; and (2) to the extent that they are, can differences can be attributed to two indices of disturbance. We implemented modeling averaged methods using five of the most common IAOR models to derive an averaged IAOR fit for each island. After testing if species colonization status (indigenous versus non-indigenous) may explain the residuals of the IAOR, we identified true negative and positive outliers and tested the effect of colonization status on the likelihood of a species being a positive or negative outlier. We found that the indigenous and non-indigenous species are randomly distributed on both sides of the overall IAOR. Only for Flores Island, were non-indigenous species more aggregated than indigenous species. We were unable to detect a meaningful relationship between deviation from the IAOR and disturbance, despite the undoubted impact of both severe habitat loss and non-indigenous species on these oceanic islands. Our results show that the non-indigenous species have been integrated alongside indigenous species in the contemporary Azorean arthropod communities such that they are mostly undetectable by the study of the IAOR.

  15. The Human Release Hypothesis for biological invasions: human activity as a determinant of the abundance of invasive plant species.

    PubMed

    Zimmermann, Heike; Brandt, Patric; Fischer, Joern; Welk, Erik; von Wehrden, Henrik

    2014-01-01

    Research on biological invasions has increased rapidly over the past 30 years, generating numerous explanations of how species become invasive. While the mechanisms of invasive species establishment are well studied, the mechanisms driving abundance patterns (i.e. patterns of population density and population size) remain poorly understood. It is assumed that invasive species typically have higher abundances in their new environments than in their native ranges, and patterns of invasive species abundance differ between invaded regions. To explain differences in invasive species abundance, we propose the Human Release Hypothesis. In parallel to the established Enemy Release Hypothesis, this hypothesis states that the differences in abundance of invasive species are found between regions because population expansion is reduced in some regions through continuous land management and associated cutting of the invasive species. The Human Release Hypothesis does not negate other important drivers of species invasions, but rather should be considered as a potentially important complementary mechanism. We illustrate the hypothesis via a case study on an invasive rose species, and hypothesize which locations globally may be most likely to support high abundances of invasive species. We propose that more extensive empirical work on the Human Release Hypothesis could be useful to test its general applicability.

  16. Tick-borne rickettsial pathogens in questing ticks, removed from humans and animals in Mexico.

    PubMed

    Sosa-Gutierrez, Carolina G; Vargas-Sandoval, Margarita; Torres, Javier; Gordillo-Pérez, Guadalupe

    2016-09-30

    Tick-borne rickettsial diseases (TBRD) are commonly encountered in medical and veterinary clinical settings. The control of these diseases is difficult, requiring disruption of a complex transmission chain involving a vertebrate host and ticks. The geographical distribution of the diseases is related to distribution of the vector, which is an indicator of risk for the population. A total of 1107 were collected by tick drag from forests, ecotourism parks and hosts at 101 sites in 22 of the 32 states of Mexico. Collected ticks were placed in 1.5 mL cryovials containing 70% ethanol and were identified to species. Ticks were pooled according to location/host of collection, date of collection, sex, and stage of development. A total of 51 ticks were assayed by polymerase chain reaction (PCR) to confirm species identification using morphological methods. A total of 477 pools of ticks were assayed using PCR techniques for selected tick-borne pathogens. Anaplasma phagocytophilum was the most commonly detected pathogen (45 pools), followed by, Ehrlichia (E.) canis (42), Rickettsia (R.) rickettsii (11), E. chaffeensis (8), and R. amblyommii (1). Rhipicephalus sanguineus was the tick most frequently positive for selected pathogens. Overall, our results indicate that potential tick vectors positive for rickettsial pathogens are distributed throughout the area surveyed in Mexico.

  17. Borrelia burgdorferi DNA absent, multiple Rickettsia spp. DNA present in ticks collected from a teaching forest in North Central Florida.

    PubMed

    Sayler, Katherine; Rowland, Jessica; Boyce, Carisa; Weeks, Emma

    2017-01-01

    Tick-borne diseases are an emerging public health threat in the United States. In Florida, there has been public attention directed towards the possibility of locally acquired Borrelia burgdorferi sensu stricto, the causative agent of Lyme disease, in association with the lone star tick. The aim of this study was to determine the prevalence of ticks and the pathogens they carry and potentially transmit, such as B. burgdorferi, in a highly utilized teaching and research forest in North Central Florida. Ticks were collected by dragging and flagging methods over a four month period in early 2014, identified, and tested by PCR for multiple pathogens including Anaplasma, Borrelia, Rickettsia, and Ehrlichia species. During the study period the following ticks were collected: 2506 (96.5%) Amblyomma americanum L., 64 (2.5%) Ixodes scapularis Say, 19 (0.7%) Dermacentor variabilis Say, and 5 (0.2%) Ixodes affinis Neuman. Neither Borrelia spp. (0/846) nor Anaplasma spp. (0/69; Ixodes spp. only) were detected by PCR in any of the ticks tested. However, Rickettsia DNA was present in 53.7% (86/160), 62.5% (40/64), 60.0% (3/5) and 31.6% (6/19) of A. americanum, I. scapularis, I. affinis and D. variabilis, respectively. Furthermore, E. chaffeensis and E. ewingii DNA were detected in 1.3% and 4.4% of adult A. americanum specimens tested, respectively. Although receiving an A. americanum bite is likely in wooded areas in North Central Florida due to the abundance of this tick, the risk of contracting a tick-borne pathogen in this specific area during the spring season appears to be low. The potential for pathogen prevalence to be highly variable exists, even within a single geographical site and longitudinal studies are needed to assess how tick-borne pathogen prevalence is changing over time in North Central Florida.

  18. Primary report on distribution of tick fauna in Iran.

    PubMed

    Rahbari, Sadegh; Nabian, Sedighe; Shayan, Parviz

    2007-09-01

    A tick survey was carried out in four different geographical areas of Iran, where the majority of the domestic ruminants in Iran exist. About 1,500 sheep, 1,200 goats and 500 cattle of 12 herds in different provinces lying in the corresponding zones were inspected for tick infestation. The occurrence of ticks on cattle, sheep and goats were 62, 55 and 57%, respectively, with no differences between the zones. The mean number of ticks on each animal was low (10-20 ticks per animal). Ixodid ticks were found throughout the year, whereas the soft tick Ornithodoros sp., which occurred in mountainous area with a significant difference in abundance, showed a clear pattern of seasonality, being generally present from November to March. The largest numbers of adult ixodid ticks were generally present from April to August. Rhipicephalus, Haemaphysalis and Dermacentor ticks occurred in the mountainous area, whereas Boophilus and Ixodes ticks were only present in the Caspian region. Hyalomma were very abundant in each zone but especially in the mountainous area, whereas Ixodes ticks were the minor genus.

  19. Convergence and divergence in a long-term old-field succession: the importance of spatial scale and species abundance.

    PubMed

    Li, Shao-Peng; Cadotte, Marc W; Meiners, Scott J; Pu, Zhichao; Fukami, Tadashi; Jiang, Lin

    2016-09-01

    Whether plant communities in a given region converge towards a particular stable state during succession has long been debated, but rarely tested at a sufficiently long time scale. By analysing a 50-year continuous study of post-agricultural secondary succession in New Jersey, USA, we show that the extent of community convergence varies with the spatial scale and species abundance classes. At the larger field scale, abundance-based dissimilarities among communities decreased over time, indicating convergence of dominant species, whereas incidence-based dissimilarities showed little temporal tend, indicating no sign of convergence. In contrast, plots within each field diverged in both species composition and abundance. Abundance-based successional rates decreased over time, whereas rare species and herbaceous plants showed little change in temporal turnover rates. Initial abandonment conditions only influenced community structure early in succession. Overall, our findings provide strong evidence for scale and abundance dependence of stochastic and deterministic processes over old-field succession.

  20. Ixodid ticks on domestic animals in Samut Prakan Province, Thailand.

    PubMed

    Nithikathkul, C; Polseela, P; Changsap, B; Leemingsawat, S

    2002-01-01

    The prevalence of tick-harboring domestic animals, tick density, and the species of ticks were studied throughout the year 2000, in Muang Samut Prakan, Bang Phli and Phra Pradaeng districts of Samut Prakan Province. The animals examined were Canis lupus familiaris (450), Bos indicus (cross-bred) (189), Bos taurus (30), Bubalus bubalis (171) and Sus scrofa domestica (450). The total number of collected ticks was 1,491. The pigs did not harbor ticks. The stages of ticks collected were larvae, nymphs and adults. The prevalence rates of tick-harboring were 46% (Canis lupus familiaris), 42.86% (Bos indicus, cross-bred), 33.33% (Bos taurus) and 9.35% (Bubalus bubalis). The tick densities were 2.22 (Bos indicus, cross-bred), 2.16 (Canis lupus familiaris), 1.16 (Bos taurus) and 0.36 (Bubalus bubalis). Only 2 species of ixodid ticks, Boophilus microplus and Rhipicephalus sanguineus, were found. R. sanguineus was the dominant species of tick. The percentage of R. sanguineus was 65.2% and B. microplus was 34.8%. In Muang district, R. sanguineus was the dominant species in C. lupus familiaris; in Bang Phli district, B. microplus was the dominant species in Bos indicus (cross-bred). The density of B. microplus was high in the summer season; the density of R. sanguineus was high in the winter season. The number of ticks depended on the geographic location, animal host and season.

  1. Infestation of urban populations of the Northern white-breasted hedgehog, Erinaceus roumanicus, by Ixodes spp. ticks in Poland.

    PubMed

    Dziemian, S; Michalik, J; Pi Łacińska, B; Bialik, S; Sikora, B; Zwolak, R

    2014-12-01

    Infestation by the nest-dwelling Ixodes hexagonus Leach and the exophilic Ixodes ricinus (Linnaeus) (Ixodida: Ixodidae) on the Northern white-breasted hedgehog, Erinaceus roumanicus (Erinaceomorpha: Erinaceidae), was investigated during a 4-year study in residential areas of the city of Poznań, west-central Poland. Of 341 hedgehogs, 303 (88.9%) hosted 10 061 Ixodes spp. ticks encompassing all parasitic life stages (larvae, nymphs, females). Ixodes hexagonus accounted for 73% and I. ricinus for 27% of the collected ticks. Male hedgehogs carried significantly higher tick burdens than females. Analyses of seasonal prevalence and abundance of I. hexagonus revealed relatively stable levels of infestation of all parasitic stages, with a modest summer peak in tick abundance noted only on male hosts. By contrast, I. ricinus females and nymphs peaked in spring and declined steadily thereafter in summer and autumn, whereas the less abundant larvae peaked in summer. This is the first longterm study to evaluate the seasonal dynamics of both tick species on populations of wild hedgehogs inhabiting urban residential areas.

  2. Microbial distribution and abundance in the digestive system of five shipworm species (Bivalvia: Teredinidae).

    PubMed

    Betcher, Meghan A; Fung, Jennifer M; Han, Andrew W; O'Connor, Roberta; Seronay, Romell; Concepcion, Gisela P; Distel, Daniel L; Haygood, Margo G

    2012-01-01

    Marine bivalves of the family Teredinidae (shipworms) are voracious consumers of wood in marine environments. In several shipworm species, dense communities of intracellular bacterial endosymbionts have been observed within specialized cells (bacteriocytes) of the gills (ctenidia). These bacteria are proposed to contribute to digestion of wood by the host. While the microbes of shipworm gills have been studied extensively in several species, the abundance and distribution of microbes in the digestive system have not been adequately addressed. Here we use Fluorescence In-Situ Hybridization (FISH) and laser scanning confocal microscopy with 16S rRNA directed oligonucleotide probes targeting all domains, domains Bacteria and Archaea, and other taxonomic groups to examine the digestive microbiota of 17 specimens from 5 shipworm species (Bankia setacea, Lyrodus pedicellatus, Lyrodus massa, Lyrodus sp. and Teredo aff. triangularis). These data reveal that the caecum, a large sac-like appendage of the stomach that typically contains large quantities of wood particles and is considered the primary site of wood digestion, harbors only very sparse microbial populations. However, a significant number of bacterial cells were observed in fecal pellets within the intestines. These results suggest that due to low abundance, bacteria in the caecum may contribute little to lignocellulose degradation. In contrast, the comparatively high population density of bacteria in the intestine suggests a possible role for intestinal bacteria in the degradation of lignocellulose.

  3. Monitoring species richness and abundance of shorebirds in the western Great Basin

    USGS Publications Warehouse

    Warnock, N.; Haig, S.M.; Oring, L.W.

    1998-01-01

    Broad-scale avian surveys have been attempted within North America with mixed results. Arid regions, such as the Great Basin, are often poorly sampled because of the vastness of the region, inacessibilty of sites, and few ornithologist. In addition, extreme variability in wetland habitat conditions present special problems for conducting censuses of species inhabiting these areas. We examined these issues in assessing multi-scale shorebird (order: Charadriiformes) censuses conducted the western Great Basin from 1992-1997. On ground surveys, we recorded 31 species of shorebirds, but were unable to accurately estimate population size. Conversely, on aerial surveys we were able to estimate regional abundance of some shorebirds, but were unable to determined species diversity. Acrial surveys of three large alkali lakcs in Oregon (Goose, Summer, and abert Lakes) revealed > 300,000 shorebirds in one year of this study, of which 67% were American Avocets (Recurvirostra americana) and 30% phalaropes (Phalaropus spp.). These lakes clearly meet Western Hemisphere Shorebird Reserve Network guidelines for designation as important shorebirds sites. Based upon simulations of our monitoring effort and the magnitude and variation of numbers of American Avocets, detection of 5-10% negative declines in population of these birds would take a minimum of 7-23 years comparable effort. We conclude that a combination of ground and aerial surveys must be conducted at multiple sites and years and over a large region to obtain an accurate picture of the diversity, abundance, and trends of shorebirds in the western Great Basin.

  4. Stream salamander species richness and abundance in relation to environmental factors in Shenandoah National Park, Virginia

    USGS Publications Warehouse

    Campbell Grant, Evan H.; Jung, Robin E.; Rice, Karen C.

    2005-01-01

    Stream salamanders are sensitive to acid mine drainage and may be sensitive to acidification and low acid neutralizing capacity (ANC) of a watershed. Streams in Shenandoah National Park, Virginia, are subject to episodic acidification from precipitation events. We surveyed 25 m by 2 m transects located on the stream bank adjacent to the water channel in Shenandoah National Park for salamanders using a stratified random sampling design based on elevation, aspect and bedrock geology. We investigated the relationships of four species (Eurycea bislineata, Desmognathus fuscus, D. monticola and Gyrinophilus porphyriticus) to habitat and water quality variables. We did not find overwhelming evidence that stream salamanders are affected by the acid-base status of streams in Shenandoah National Park. Desmognathus fuscus and D. monticola abundance was greater both in streams that had a higher potential to neutralize acidification, and in higher elevation (>700 m) streams. Neither abundance of E. bislineata nor species richness were related to any of the habitat variables. Our sampling method preferentially detected the adult age class of the study species and did not allow us to estimate population sizes. We suggest that continued monitoring of stream salamander populations in SNP will determine the effects of stream acidification on these taxa.

  5. Tick-borne pathogens in ticks collected from breeding and migratory birds in Switzerland.

    PubMed

    Lommano, Elena; Dvořák, Charles; Vallotton, Laurent; Jenni, Lukas; Gern, Lise

    2014-10-01

    From 2007 to 2010, 4558 migrating and breeding birds of 71 species were caught and examined for ticks in Switzerland. A total of 1205 specimens were collected; all were Ixodes ricinus ticks except one Ixodes frontalis female, which was found on a common chaffinch (Fringilla coelebs) for the first time in Switzerland. Each tick was analysed individually for the presence of Borrelia spp., Rickettsia spp., Anaplasma phagocytophilum and tick-borne encephalitis virus (TBEV). Altogether, 11.4% of birds (22 species) were infested by ticks and 39.8% of them (15 species) were carrying infected ticks. Bird species belonging to the genus Turdus were the most frequently infested with ticks and they were also carrying the most frequently infected ticks. Each tick-borne pathogen for which we tested was identified within the sample of bird-feeding ticks: Borrelia spp. (19.5%) and Rickettsia helvetica (10.5%) were predominantly detected whereas A. phagocytophilum (2%), Rickettsia monacensis (0.4%) and TBEV (0.2%) were only sporadically detected. Among Borrelia infections, B. garinii and B. valaisiana were largely predominant followed by B. afzelii, B. bavariensis, B. miyamotoi and B. burgdorferi ss. Interestingly, Candidatus Neoehrlichia mikurensis was identified in a few ticks (3.3%), mainly from chaffinches. Our study emphasizes the role of birds in the natural cycle of tick-borne pathogens that are of human medical and veterinary relevance in Europe. According to infection detected in larvae feeding on birds we implicate the common blackbird (Turdus merula) and the tree pipit (Anthus trivialis) as reservoir hosts for Borrelia spp., Rickettsia spp. and A. phagocytophilum.

  6. Distribution and abundance of decapod crustacean larvae in the southeastern Bering Sea with emphasis on commercial species. Final report

    SciTech Connect

    Armstrong, D.A.; Incze, L.S.; Wencker, D.L.; Armstrong, J.L.

    1981-01-01

    Contents include: Distribution and abundance of king crab larvae, Paralithodes camtschatica and P. platypus in the southeast Bering Sea; Distribution and abundance of the larvae of tanner crabs in the southeastern Bering Sea; Distribution and abundance of other brachyuran larvae in the southeastern Bering Sea with emphasis on Erimacrus isenbeckii; Distribution and abundance of shrimp larvae in the southeastern Bering Sea with emphasis on pandalid species; Distribution and abundance of hermit crabs (Paguridae) in the southeasternBering Sea; Possible oil impacts on decapod larbae in the southeastern Bering Sea with emphesis on the St. George Basin.

  7. Abundance of Woody Riparian Species in the Western USA in Relation to Phenology, Climate, and Flow Regime

    NASA Astrophysics Data System (ADS)

    Auble, G. T.; Friedman, J. M.; Scott, M. L.; Shafroth, P. B.; Merigliano, M. M.; Freehling, M. D.; Evans, R. E.; Griffin, E. R.

    2004-12-01

    We randomly selected 475 long-term U.S. Geological Survey stream gaging stations in 17 western states to relate the presence and abundance of woody species to environmental factors. Along a 1.3-km reach near each station we measured the cover of all species on a list of the 44 most abundant large woody riparian species in the region. We used logistic regression to fit the response of four abundant species to growing degree days and mean precipitation. Then we related relative abundance of these 4 species to timing of the flood peak in sites where the likelihood of occurrence was greater than 0.5. The exotics Tamarix ramosissima (saltcedar) and Elaeagnus angustifolia (Russian-olive) are now the third and fourth most frequently occurring large woody riparian species in the western U.S. and the second and fifth most abundant. In climatically suitable areas, species differences in reproductive phenology produce different relations of abundance to flow regime. Because of its limited period of seed release and viability in early summer, cottonwood (Populus deltoides) is disadvantaged where floods occur in the spring or fall. Abundances of saltcedar, because of its long period of seed release; Russian-olive, because of seed dormancy; and Salix exigua, because of the importance of vegetative spread, are much less sensitive to flood timing.

  8. Environmental correlates of abundances of mosquito species and stages in discarded vehicle tires.

    PubMed

    Yee, Donald A; Kneitel, Jamie M; Juliano, Steven A

    2010-01-01

    Discarded vehicle tires are a common habitat for container mosquito larvae, although the environmental factors that may control their presence or abundance within a tire are largely unknown. We sampled discarded vehicle tires in six sites located within four counties of central Illinois during the spring and summer of 2006 to determine associations between a suite of environmental factors and community composition of container mosquitoes. Our goal was to find patterns of association between environmental factors and abundances of early and late instars. We hypothesized that environmental factors correlated with early instars would be indicative of oviposition cues, whereas environmental factors correlated with late instars would be those important for larval survival. We collected 13 species of mosquitoes, with six species (Culex restuans, Cx. pipiens, Aedes albopictus, Cx. salinarius, Ae. atropalpus, and Ae. triseriatus) accounting for r95% of all larvae. There were similar associations between congenerics and environmental factors, with Aedes associated with detritus type (fine detritus, leaves, seeds) and Culex associated with factors related to the surrounding habitat (human population density, canopy cover, tire size) or microorganisms (bacteria, protozoans). Although there was some consistency in factors that were important for early and late instar abundance, there were few significant associations between early and late instars for individual species. Lack of correspondence between factors that explain variation in early versus late instars, most notable for Culex, suggests a difference between environmental determinants of oviposition and survival within tires. Environmental factors associated with discarded tires are important for accurate predictions of mosquito occurrence at the generic level.

  9. Ticks and tick-borne viruses from livestock hosts in arid and semiarid regions of the eastern and northeastern parts of Kenya.

    PubMed

    Lutomiah, Joel; Musila, Lillian; Makio, Albina; Ochieng, Caroline; Koka, Hellen; Chepkorir, Edith; Mutisya, James; Mulwa, Francis; Khamadi, Samoel; Miller, Barry R; Bast, Joshua; Schnabel, David; Wurapa, Eyako K; Sang, Rosemary

    2014-01-01

    Biodiversity and relative abundance of ticks and associated arboviruses in Garissa (northeastern) and Isiolo (eastern) provinces of Kenya were evaluated. Ticks were collected from livestock, identified to species, pooled, and processed for virus isolation. In Garissa, Rhipicephalus pulchellus Gerstacker (57.8%) and Hyalomma truncatum Koch (27.8%) were the most abundant species sampled, whereas R. pulchellus (80.4%) and Amblyomma gemma Donitz (9.6%) were the most abundant in Isiolo. Forty-four virus isolates, comprising Dugbe virus (DUGV; n = 22) and Kupe virus (n = 10; Bunyaviridae: Nirovirus), Dhori virus (DHOV; n = 10; Orthomyxoviridae: Thogotovirus),and Ngari virus (NRIV; n = 2; Bunyaviridae: Orthobunyavirus), were recovered mostly from R. pulchellus sampled in Isiolo. DUGV was mostly recovered from R. pulchellus from sheep and cattle, and DHOV from R. pulchellus from sheep. All Kupe virus isolates were from Isiolo ticks, including R. pulchellus from all the livestock, A. gemma and Amblyomma variegatum F. from cattle, and H. truncatum from goat. NRIV was obtained from R. pulchellus and A. gemma sampled from cattle in Isiolo and Garissa, respectively, while all DHOV and most DUGV (n = 12) were from R. pulchellus sampled from cattle in Garissa. DUGV was also recovered from H. truncatum and Amblyomma hebraeum Koch from cattle and from Rhipicephalus annulatus Say from camel. This surveillance study has demonstrated the circulation of select tick-borne viruses in parts of eastern and northeastern provinces of Kenya, some of which are of public health importance. The isolation of NRIV from ticks is particularly significant because it is usually known to be a mosquito-borne virus affecting humans.

  10. Abundance and species richness of Coreoidea (Hemiptera: Heteroptera) from Parque Estadual do Turvo, Southern Brazil.

    PubMed

    Barcellos, Aline; Schmidt, Letícia S; Brailovsky, Harry

    2008-01-01

    The coreoid fauna from Neotropics is poorly known, especially in terms of community studies. Aiming at contributing to this knowledge, a two-year study was carried out at Parque Estadual do Turvo, Municipality of Derrubadas, state of Rio Grande do Sul, Brazil, to evaluate the composition, abundance and species richness of Coreoidea. Samplings were conducted in the springs of 2003 and 2004 (October), and autumns of 2004 and 2005 (May), using beating tray method, along two trails of the park. Sampling effort (hours X collectors) totaled 153h. A total of 282 individuals of Coreoidea were collected, distributed in 28 species of Alydidae, Coreidae and Rhopalidae. The most abundant species was the coreid Cebrenis supina Brailovsky, representing 16% of the collected individuals, followed by the rhopalids Jadera aeola (Dallas), and Harmostes sp., with 12.1% and 11.7%, respectively. The estimated richnesses by Chao 1, Chao 2, Jackknife 1 and Jackknife 2 indicated that the observed richness corresponds to 70% to 80% of the expected for the area. The estimated richness through rarefaction was significantly higher in spring 2003 and autumn 2004 than in the other periods. There was no significant difference, however, between spring of 2003 and autumn of 2004, and between spring of 2004 and autumn of 2005, for the same parameter. Yucumã and Garcia trails did not differ significantly for the estimated richness. Singletons and doubletons represented 32.1% of the recorded species. Additionally, eight other species were obtained qualitatively by using, besides beating tray without protocol, manual collection.

  11. Assessing Landscape Constraints on Species Abundance: Does the Neighborhood Limit Species Response to Local Habitat Conservation Programs?

    PubMed Central

    Jorgensen, Christopher F.; Powell, Larkin A.; Lusk, Jeffery J.; Bishop, Andrew A.; Fontaine, Joseph J.

    2014-01-01

    Landscapes in agricultural systems continue to undergo significant change, and the loss of biodiversity is an ever-increasing threat. Although habitat restoration is beneficial, management actions do not always result in the desired outcome. Managers must understand why management actions fail; yet, past studies have focused on assessing habitat attributes at a single spatial scale, and often fail to consider the importance of ecological mechanisms that act across spatial scales. We located survey sites across southern Nebraska, USA and conducted point counts to estimate Ring-necked Pheasant abundance, an economically important species to the region, while simultaneously quantifying landscape effects using a geographic information system. To identify suitable areas for allocating limited management resources, we assessed land cover relationships to our counts using a Bayesian binomial-Poisson hierarchical model to construct predictive Species Distribution Models of relative abundance. Our results indicated that landscape scale land cover variables severely constrained or, alternatively, facilitated the positive effects of local land management for Ring-necked Pheasants. PMID:24918779

  12. Ehrlichia minasensis sp. nov., a new species within the genus Ehrlichia isolated from the tick Rhipicephalus microplus.

    PubMed

    Cabezas-Cruz, Alejandro; Zweygarth, Erich; Vancová, Marie; Broniszewska, Marzena; Grubhoffer, Libor; Passos, Lygia Maria Friche; Ribeiro, Múcio Flávio Barbosa; Alberdi, Pilar; de la Fuente, José

    2016-01-12

    Recently, we obtained a rickettsial isolate (Ehrlichia sp. UFMG-EV) from the hemolymph of Rhipicephalus microplus engorged tick females. On the basis of maximum likelihood phylogenetic analysis using 16S rRNA, groEL, dsb, gltA and trp36 nucleotide sequences we showed that Ehrlichia sp. UFMG-EV belongs to the α-Proteobacteria, family Anaplasmataceae, genus Ehrlichia. Ehrlichia sp. UFMG-EV is a sister taxa of E. canis with 16S rRNA, groEL, dsb, gltA and trp36 nucleotide sequence similarity of 98.3%, 97.2%, 94.7%, 94.3% and 49.1%, respectively. Ehrlichia sp. UFMG-EV has been maintained in the laboratory by continuous passage in the IDE8 tick cell line where the ultrastructure was characterized using electron microscopy and it resembles that of E. canis, E. muris and E. chaffensis, but not E. ruminantium and E. ewingii. We propose the name Ehrlichia minasensis sp. nov. for this bacterium to acknowledge the place from where it was isolate for first time, Minas Gerais, Brazil. The type strain of Ehrlichia minasensis sp. nov. is strain Ehrlichia sp. UFMG-EV (= DSM 100393, = TCB-TBB-0018).

  13. Do the ticks of birds at an important migratory hotspot reflect the seasonal dynamics of Ixodes ricinus at the migration initiation site? A case study in the Danube Delta.

    PubMed

    Sándor, Attila D; Mărcuţan, Daniel I; D'Amico, Gianluca; Gherman, Călin M; Dumitrache, Mirabela O; Mihalca, Andrei D

    2014-01-01

    Migratory birds play important roles as distributors of ticks within and between continents. In the Old World, the most important migratory route of birds links Asia, Europe and Africa. During their migration, birds use various stopover sites, where they feed and rest and where ticks may attach or detach, creating new natural foci for vector-borne diseases. Danube Delta is one of the most important migration hotspots and so far no studies were focused on ticks of migratory birds herein. The aim of the present study was to assess the species diversity and seasonal dynamics of ticks parasitizing migratory birds in Danube Delta Biosphere Reserve. Migratory birds were trapped on Grindul Lupilor (44°41'N; 28°56'E) using mist nets during 4 migratory seasons (2 spring and 2 autumn) in 2011 and 2012. From each bird, all the ticks were collected and identified based on morphological features. Epidemiological parameters (prevalence, mean abundance, mean intensity) were calculated and all data were analysed statistically based on the season (spring and autumn), regional status of birds (migrants and breeding) and foraging behaviour (ground feeders, reed-bed feeders, foliage feeders). A total of 1434 birds (46 species) were captured. Ticks were found on 94 birds (10 species). Significantly more migratory birds hosted ticks, compared to resident birds. The 400 collected ticks belonged to four species: Ixodes ricinus (92.25%), I. arboricola (6.25%), I. redikorzevi (1.00%) and Haemaphysalis punctata (0.50%). A higher prevalence was found for I. ricinus in spring, with higher prevalence of nymphs in this season, while larvae occurred with the same prevalence in both seasons. Larval intensity was higher during spring and nymphs were more abundant during autumn. The seasonal differences in our study may be related not to the local seasonal dynamics of ticks, but on the seasonal dynamics at the site of migration initiation.

  14. Do the Ticks of Birds at an Important Migratory Hotspot Reflect the Seasonal Dynamics of Ixodes ricinus at the Migration Initiation Site? A Case Study in the Danube Delta

    PubMed Central

    Sándor, Attila D.; Mărcuţan, Daniel I.; D'Amico, Gianluca; Gherman, Călin M.; Dumitrache, Mirabela O.; Mihalca, Andrei D.

    2014-01-01

    Migratory birds play important roles as distributors of ticks within and between continents. In the Old World, the most important migratory route of birds links Asia, Europe and Africa. During their migration, birds use various stopover sites, where they feed and rest and where ticks may attach or detach, creating new natural foci for vector-borne diseases. Danube Delta is one of the most important migration hotspots and so far no studies were focused on ticks of migratory birds herein. The aim of the present study was to assess the species diversity and seasonal dynamics of ticks parasitizing migratory birds in Danube Delta Biosphere Reserve. Migratory birds were trapped on Grindul Lupilor (44°41′N; 28°56′E) using mist nets during 4 migratory seasons (2 spring and 2 autumn) in 2011 and 2012. From each bird, all the ticks were collected and identified based on morphological features. Epidemiological parameters (prevalence, mean abundance, mean intensity) were calculated and all data were analysed statistically based on the season (spring and autumn), regional status of birds (migrants and breeding) and foraging behaviour (ground feeders, reed-bed feeders, foliage feeders). A total of 1434 birds (46 species) were captured. Ticks were found on 94 birds (10 species). Significantly more migratory birds hosted ticks, compared to resident birds. The 400 collected ticks belonged to four species: Ixodes ricinus (92.25%), I. arboricola (6.25%), I. redikorzevi (1.00%) and Haemaphysalis punctata (0.50%). A higher prevalence was found for I. ricinus in spring, with higher prevalence of nymphs in this season, while larvae occurred with the same prevalence in both seasons. Larval intensity was higher during spring and nymphs were more abundant during autumn. The seasonal differences in our study may be related not to the local seasonal dynamics of ticks, but on the seasonal dynamics at the site of migration initiation. PMID:24586732

  15. Water Mites (Acari: Hydrachnida) of Ozark Streams - Abundance, Species Richness, and Potential as Environmental Indicators

    NASA Astrophysics Data System (ADS)

    Radwell, A. J.; Brown, A. V.

    2005-05-01

    Because water mites are tightly linked to other stream metazoans through parasitism and predation, they are potentially effective indicators of environmental quality. Meiofauna (80 μm to 1 mm) were sampled from headwater riffles of 11 Ozark streams to determine relative abundance and densities of major meiofauna taxa. Water mites comprised 15.3% of the organisms collected exceeded only by chironomids (50.2%) and oligochaetes (17.8%), and mean water mite density among the 11 streams was 265 organisms per liter. The two streams that differed the most in environmental quality were sampled using techniques suitable for identification of species. An estimated 32 species from 20 genera and 13 families were found in the least disturbed stream; an estimated 19 species from 13 genera and 8 families were found in the most disturbed stream. This preliminary finding supports the notion that water mite species richness declines in response to environmental disturbance. Many species could only be identified as morphospecies of particular genera, but the ongoing taxonomic revision of Hydrachnida is expected to provide needed information. A collaborative effort between those interested in taxonomy/systematics of water mites and ecologists interested in the significance of water mites in aquatic communities could prove mutually beneficial.

  16. [The abundance and distribution of the Ixodes persulcatus (Acari: Ixodidae) near its northern spreading limit in the Ural Mountains].

    PubMed

    Livanova, N N; Livanov, S G

    2006-01-01

    A count of the tick species Ixodes persulcatus Schulze, 1930 was carried out in the "Denezhkin Kamen" Nature Reserve and adjacent territories (the Severoural'sk and Ivdel' Districts of the Sverdlovsk Region, the Northern Urals geographical province) in the 2005. The abundance and distribution of unengorged adults has been evaluated on an area of 22.5 square kilometers (N 60 degrees 27'-60 degrees 30' E 059 degrees 38'-059 degrees 42'). The area includes proportionally main landscape and vegetation elements of the region studied, from mountain analogues of the middle and northern taiga up to tundra. One tick species, I. persulcatus, has been collected by flagging with the abundance from 0.4 up to 6.8 (average 1.6 +/- 0.9) specimens per flag-hour. The observed values of abundance are classified into three classes (I - ticks are absent, II - 1-2 specimens, and III - 3-7 specimens per flag-hour). The class I amounts 20, II - 75, and III - 5% of the area examined. It has been revealed by the expert evaluation of the 2003-2004 and counts of the 2005 that ticks occur stably in the Northern Ural, reaching N 61 degrees and 400 m above sea level. The level of the species abundance remained constant till the middle of summer. In this period the activity of ticks dependent on the weather optimum only.

  17. The ecology of ticks and epidemiology of tick-borne viral diseases.

    PubMed

    Estrada-Peña, Agustín; de la Fuente, José

    2014-08-01

    A number of tick-borne diseases of humans have increased in incidence and geographic range over the past few decades, and there is concern that they will pose an even greater threat to public health in future. Although global warming is often cited as the underlying mechanism favoring the spread of tick-borne diseases, climate is just one of many factors that determine which tick species are found in a given geographic region, their population density, the likelihood that they will be infected with microbes pathogenic for humans and the frequency of tick-human contact. This article provides basic information needed for microbiologists to understand the many factors that affect the geographic range and population density of ticks and the risk of human exposure to infected ticks. It first briefly summarizes the life cycle and basic ecology of ticks and how ticks and vertebrate hosts interact, then reviews current understanding of the role of climate, sociodemographic factors, agricultural development and changes in human behavior that affect the incidence of tick-borne diseases. These concepts are then illustrated in specific discussions of tick-borne encephalitis and Crimean-Congo hemorrhagic fever.

  18. Differences in ecological structure, function, and native species abundance between native and invaded Hawaiian streams.

    PubMed

    Holitzki, Tara M; MacKenzie, Richard A; Wiegner, Tracy N; McDermid, Karla J

    2013-09-01

    Poeciliids, one of the most invasive species worldwide, are found on almost every continent and have been identified as an "invasive species of concern" in the United States, New Zealand, and Australia. Despite their global prevalence, few studies have quantified their impacts on tropical stream ecosystem structure, function, and biodiversity. Utilizing Hawaiian streams as model ecosystems, we documented how ecological structure, function, and native species abundance differed between poeciliid-free and poeciliid-invaded tropical streams. Stream nutrient yields, benthic biofilm biomass, densities of macroinvertebrates and fish, and community structures of benthic algae, macroinvertebrates, and fish were compared between streams with and without established poeciliid populations on the island of Hawai'i, Hawaii, USA. Sum nitrate (sigmaNO3(-) = NO3(-) + NO2(-)), total nitrogen, and total organic carbon yields were eight times, six times, and five times higher, respectively, in poeciliid streams than in poeciliid-free streams. Benthic biofilm ash-free dry mass was 1.5x higher in poeciliid streams than in poeciliid-free streams. Percentage contributions of chironomids and hydroptilid caddisflies to macroinvertebrate densities were lower in poeciliid streams compared to poeciliid-free streams, while percentage contributions of Cheumatopsyche analis caddisflies, Dugesia sp. flatworms, and oligochaetes were higher. Additionally, mean densities of native gobies were two times lower in poeciliid streams than in poeciliid-free ones, with poeciliid densities being approximately eight times higher than native fish densities. Our results, coupled with the wide distribution of invasive poeciliids across Hawaii and elsewhere in the tropics, suggest that poeciliids may negatively impact the ecosystem structure, function, and native species abundance of tropical streams they invade. This underscores the need for increased public awareness to prevent future introductions and for

  19. Host specialization in ticks and transmission of tick-borne diseases: a review.

    PubMed

    McCoy, Karen D; Léger, Elsa; Dietrich, Muriel

    2013-01-01

    Determining patterns of host use, and the frequency at which these patterns change, are of key importance if we are to understand tick population dynamics, the evolution of tick biodiversity, and the circulation and evolution of associated pathogens. The question of whether ticks are typically host specialists or host generalists has been subject to much debate over the last half-century. Indeed, early research proposed that morphological diversity in ticks was linked to host specific adaptations and that most ticks were specialists. Later work disputed this idea and suggested that ticks are largely limited by biogeographic conditions and tend to use all locally available host species. The work presented in this review suggests that the actual answer likely lies somewhere between these two extremes. Although recent observational studies support the view that phylogenetically diverse host species share ticks when found on similar ecological ranges, theory on host range evolution predicts that host specialization should evolve in ticks given their life history characteristics. Contemporary work employing population genetic tools to examine host-associated population structure in several tick systems support this prediction and show that simple species records are not enough to determine whether a parasite is a true host generalist; host specialization does evolve in ticks at local scales, but may not always lead to speciation. Ticks therefore seem to follow a pattern of being global generalists, local specialists. Given this, the notion of host range needs to be modified from an evolutionary perspective, where one simply counts the number of hosts used across the geographic distribution, to a more ecological view, where one considers host use at a local scale, if we are to better understand the circulation of tick-borne pathogens and exposure risks for humans and livestock.

  20. Host specialization in ticks and transmission of tick-borne diseases: a review

    PubMed Central

    McCoy, Karen D.; Léger, Elsa; Dietrich, Muriel

    2013-01-01

    Determining patterns of host use, and the frequency at which these patterns change, are of key importance if we are to understand tick population dynamics, the evolution of tick biodiversity, and the circulation and evolution of associated pathogens. The question of whether ticks are typically host specialists or host generalists has been subject to much debate over the last half-century. Indeed, early research proposed that morphological diversity in ticks was linked to host specific adaptations and that most ticks were specialists. Later work disputed this idea and suggested that ticks are largely limited by biogeographic conditions and tend to use all locally available host species. The work presented in this review suggests that the actual answer likely lies somewhere between these two extremes. Although recent observational studies support the view that phylogenetically diverse host species share ticks when found on similar ecological ranges, theory on host range evolution predicts that host specialization should evolve in ticks given their life history characteristics. Contemporary work employing population genetic tools to examine host-associated population structure in several tick systems support this prediction and show that simple species records are not enough to determine whether a parasite is a true host generalist; host specialization does evolve in ticks at local scales, but may not always lead to speciation. Ticks therefore seem to follow a pattern of being global generalists, local specialists. Given this, the notion of host range needs to be modified from an evolutionary perspective, where one simply counts the number of hosts used across the geographic distribution, to a more ecological view, where one considers host use at a local scale, if we are to better understand the circulation of tick-borne pathogens and exposure risks for humans and livestock. PMID:24109592

  1. Seasonal dynamics of ixodid ticks on wild rabbits Oryctolagus cuniculus (Leporidae) from Central Spain.

    PubMed

    González, J; Valcárcel, F; Pérez-Sánchez, J L; Tercero-Jaime, J M; Olmeda, A S

    2016-11-01

    Rabbit Hemorrhagic Disease and Myxomatosis caused a decline in the rabbit population in the second half of the last century. Despite some recovery, the risk of vector-borne disease is present and thus the importance of controlling vector populations. In the current study, we describe the ixodid tick fauna in wild rabbit in a natural reserve in Ciudad Real (Central Spain) during the course of two 3-year periods (2007-2009 and 2012-2014). Of all the ticks collected on average 72.5 % were larvae, 24.4 % nymphs and 3.1 % adults, although the percentage varied monthly. Seven tick species were identified: Hyalomma lusitanicum Koch (Parasitic indicator [PI] = number of ticks per examined rabbit = 96.47), Rhipicephalus pusillus Gil Collado (PI = 47.37), Haemaphysalis hispanica Gil Collado (PI = 12.15), Ixodes ventalloi Gil Collado (PI = 0.65), R. bursa Canestrini and Fanzago (PI = 0.18), R. sanguineus Latreille (PI = 0.11), Dermacentor marginatus Sulzer (PI = 0.01). In spring and summer, most abundant were larvae of H. lusitanicum, followed by immature stages of R. pusillus and Ha. hispanica. In autumn, the main tick species were nymphs of I. ventalloi whereas in winter adults of Ha. hispanica were more numerous. Rhipicephalus pusillus was present all year long, although not always in high percentage. PI of other species (R. bursa, R. sanguineus and D. marginatus) were too low to be representative. The seasonal dynamics of ticks on wild rabbit defined in this study could be useful to design species-specific control strategies.

  2. Shrub encroachment affects mammalian carnivore abundance and species richness in semiarid rangelands

    NASA Astrophysics Data System (ADS)

    Blaum, Niels; Rossmanith, Eva; Popp, Alexander; Jeltsch, Florian

    2007-01-01

    Shrub encroachment due to overgrazing has led to dramatic changes of savanna landscapes and is considered to be one of the most threatening forms of rangeland degradation e.g. via habitat fragmentation. Mammalian carnivores are particularly vulnerable to local extinction in fragmented landscapes. However, our understanding of how shrub encroachment affects mammalian carnivores is poor. Here we investigated the relative sensitivities of ten native carnivores to different levels of shrub cover ranging from low (<5%) to high shrub cover (>25%) in 20 southern Kalahari rangeland sites. Relative abundance of carnivores was monitored along 40 sand transects (5 m × 250 m) for each site. Our results show that increasing shrub cover affects carnivore species differently. African wild cats, striped polecats, cape foxes and suricates were negatively affected, whereas we found hump-shaped responses for yellow mongooses, bat-eared foxes and small-spotted genets with maximum abundance at shrub covers between 10 and 18%. In contrast, black-backed jackals, slender mongooses and small spotted cats were not significantly affected by increasing shrub cover. However, a negative impact of high shrub cover above 18% was congruent for all species. We conclude that intermediate shrub cover (10-18%) in savanna landscapes sustain viable populations of small carnivores.

  3. Species richness and abundance of forest birds in relation to radiation at Chernobyl.

    PubMed

    Moller, A P; Mousseau, T A

    2007-10-22

    The effects of low-level radiation on the abundance of animals are poorly known, as are the effects on ecosystems and their functioning. Recent conclusions from the UN Chernobyl forum and reports in the popular media concerning the effects of radiation from Chernobyl on animals have left the impression that the Chernobyl exclusion zone is a thriving ecosystem, filled with an increasing number of rare species. Surprisingly, there are no standardized censuses of common animals in relation to radiation, leaving the question about the ecological effects of radiation unresolved. We conducted standardized point counts of breeding birds at forest sites around Chernobyl differing in level of background radiation by over three orders of magnitude. Species richness, abundance and population density of breeding birds decreased with increasing level of radiation, even after controlling statistically for the effects of potentially confounding factors such as soil type, habitat and height of the vegetation. This effect was differential for birds eating soil invertebrates living in the most contaminated top soil layer. These results imply that the ecological effects of Chernobyl on animals are considerably greater than previously assumed.

  4. How climate warming impacts the distribution and abundance of two small flatfish species in the North Sea

    NASA Astrophysics Data System (ADS)

    van Hal, Ralf; Smits, Kalle; Rijnsdorp, Adriaan D.

    2010-07-01

    Climate change, specifically temperature, affects the distribution and densities of species in marine and terrestrial ecosystems. Here, we looked at the effect of temperature during winter and spawning period on latitudinal range shifts and changes in abundance of two non-commercial North Sea fish species, solenette ( Buglossidium luteum) and scaldfish ( Arnoglossus laterna). Both species have increased in abundance and moved to the north since the late 1980s, coinciding with a series of mild winters. In 1996, following a very cold winter, the abundance of both species temporarily decreased as they retracted to the south. The shift in temperature affected adult habitat conditions, allowing them to immigrate into new areas where they subsequently reproduced successfully. We can conclude this because recruitment improved following the increase in abundance. The recruitment relates significantly to the higher adult stock and higher temperatures. The predictions of higher average temperatures and milder winters in the North Sea make it likely that these species will increase further in abundance and move northward. The observed increase in abundance of these small flatfish species will affect the North Sea food web and therefore commercial species, e.g. plaice, by predation on juveniles and competition for benthic food resources.

  5. Tick (Amblyomma chabaudi) infestation of endemic tortoises in southwest Madagascar and investigation of tick-borne pathogens.

    PubMed

    Ehlers, Julian; Ganzhorn, Jörg U; Silaghi, Cornelia; Krüger, Andreas; Pothmann, Daniela; Ratovonamana, R Yedidya; Veit, Alexandra; Keller, Christian; Poppert, Sven

    2016-03-01

    Little is known about the role of endemic ticks as vectors for bacterial and protozoan pathogens for animals and humans in Madagascar and their interaction in anthropogenic habitats where humans, their livestock and native Malagasy species (vectors and hosts) come into more frequent contact than in natural forest ecosystems. The aims of the study were (1) to test whether habitat degradation is associated with increased infestation of tortoises by ticks and (2) to investigate whether ticks carried Babesia, Borrelia or Rickettsia species that might be pathogenic for humans and livestock. We studied hard ticks of two endemic Malagasy tortoises, Astrochelys radiata and Pyxis arachnoides in March and April 2013 in southwest Madagascar. Two tortoise habitats were compared, the National Park of Tsimanampetsotsa and the adjacent degraded pasture and agricultural land at the end of the wet season. Ticks were screened for protozoan and bacterial pathogens via PCR on DNA isolated from ticks using genus-specific primers. Only one out of 42 A. radiata collected from both habitats had ticks. The low prevalence did not allow further analyses of the effect of habitat degradation. Forty-two P. arachnoides were found in the anthropogenic habitat and 36 individuals in the national park. Tick infestation rates of P. arachnoides differed significantly between the two study sites. Tortoises inside the park had lower tick prevalence than outside (8 of 36 (22%) versus 32 of 42 individuals (76%)) and infected animals tended to have fewer ticks inside than outside the park. All ticks collected in both habitats were adults of the ixodid tick Amblyomma chabaudi, which is supposed to be a host-specific tick of P. arachnoides. Screening for Borrelia sp. and Babesia sp. was negative in all ticks. But all A. chabaudi ticks were infected with Rickettsia africae, known to cause spotted fever in humans. Thus, habitat degradation seems to be linked to higher infestation of tortoises with ticks with

  6. Habitat fragmentation and effects of herbivore (howler monkey) abundances on bird species richness.

    PubMed

    Feeley, Kenneth J; Terborgh, John W

    2006-01-01

    Habitat fragmentation can alter herbivore abundances, potentially causing changes in the plant community that can propagate through the food web and eventually influence other important taxonomic groups such as birds. Here we test the relationship between the density of red howler monkeys (Alouatta seniculus) and bird species richness on a large set of recently isolated land-bridge islands in Lago Guri, Venezuela (n = 29 islands). Several of these islands host relict populations of howler monkeys at densities up to more than 30 times greater than those on the mainland. These "hyperabundant" herbivores previously have been shown to have a strong positive influence on aboveground plant productivity. We predicted that this should lead to a positive, indirect effect of howler monkey density on bird species richness. After accounting for passive sampling (the tendency for species richness to be positively associated with island area, regardless of differences in habitat quality) we found a significant positive correlation between howler monkey density and bird species richness. A path analysis incorporating data on tree growth rates from a subset of islands (n = 9) supported the hypothesis that the effect of howler monkeys on the resident bird communities is indirect and is mediated through changes in plant productivity and habitat quality. These results highlight the potential for disparate taxonomic groups to be related through indirect interactions and trophic cascades.

  7. Variation in predator species abundance can cause variable selection pressure on warning signaling prey

    PubMed Central

    Valkonen, Janne K; Nokelainen, Ossi; Niskanen, Martti; Kilpimaa, Janne; Björklund, Mats; Mappes, Johanna

    2012-01-01

    Predation pressure is expected to drive visual warning signals to evolve toward conspicuousness. However, coloration of defended species varies tremendously and can at certain instances be considered as more camouflaged rather than conspicuous. Recent theoretical studies suggest that the variation in signal conspicuousness can be caused by variation (within or between species) in predators' willingness to attack defended prey or by the broadness of the predators' signal generalization. If some of the predator species are capable of coping with the secondary defenses of their prey, selection can favor reduced prey signal conspicuousness via reduced detectability or recognition. In this study, we combine data collected during three large-scale field experiments to assess whether variation in avian predator species (red kite, black kite, common buzzard, short-toed eagle, and booted eagle) affects the predation pressure on warningly and non-warningly colored artificial snakes. Predation pressure varied among locations and interestingly, if common buzzards were abundant, there were disadvantages to snakes possessing warning signaling. Our results indicate that predator community can have important consequences on the evolution of warning signals. Predators that ignore the warning signal and defense can be the key for the maintenance of variation in warning signal architecture and maintenance of inconspicuous signaling. PMID:22957197

  8. Novel Rickettsia and emergent tick-borne pathogens: A molecular survey of ticks and tick-borne pathogens in Shimba Hills National Reserve, Kenya.

    PubMed

    Mwamuye, Micky M; Kariuki, Edward; Omondi, David; Kabii, James; Odongo, David; Masiga, Daniel; Villinger, Jandouwe

    2017-02-01

    Ticks are important vectors of emerging and re-emerging zoonoses, the majority of which originate from wildlife. In recent times, this has become a global public health concern that necessitates surveillance of both known and unknown tick-borne pathogens likely to be future disease threats, as well as their tick vectors. We carried out a survey of the diversity of ticks and tick-borne pathogens in Kenya's Shimba Hills National Reserve (SHNR), an area with intensified human-livestock-wildlife interactions, where we collected 4297 questing ticks (209 adult ticks, 586 nymphs and 3502 larvae). We identified four tick species of two genera (Amblyomma eburneum, Amblyomma tholloni, Rhipicephalus maculatus and a novel Rhipicephalus sp.) based on both morphological characteristics and molecular analysis of 16S rRNA, internal transcribed spacer 2 (ITS 2) and cytochrome oxidase subunit 1 (CO1) genes. We pooled the ticks (3-8 adults, 8-15 nymphs or 30 larvae) depending on species and life-cycle stages, and screened for bacterial, arboviral and protozoal pathogens using PCR with high-resolution melting analysis and sequencing of unique melt profiles. We report the first molecular detection of Anaplasma phagocytophilum, a novel Rickettsia-like and Ehrlichia-like species, in Rh. maculatus ticks. We also detected Ehrlichia chaffeensis, Coxiella sp., Rickettsia africae and Theileria velifera in Am. eburneum ticks for the first time. Our findings demonstrate previously unidentified tick-pathogen relationships and a unique tick diversity in the SHNR that may contribute to livestock, and possibly human, morbidity in the region. This study highlights the importance of routine surveillance in similar areas to elucidate disease transmission dynamics, as a critical component to inform the development of better tick-borne disease diagnosis, prevention and control measures.

  9. Molecular evidence for tick-borne encephalitis virus in ticks in South Korea.

    PubMed

    Kim, S Y; Jeong, Y E; Yun, S-M; Lee, I Y; Han, M G; Ju, Y R

    2009-03-01

    To investigate whether tick-borne encephalitis viruses (TBEVs) are present in South Korea, Korean ixodid ticks were tested for TBEV RNA. Ticks (n = 2460) were collected from wild and domestic animals or by flagging at forest and grassland in 12 regions of five provinces in 2005-06. Four species in two genera were identified, yielding 197 sample pools (1-20 ticks per pool); from these, 12 envelope protein gene fragments of TBEV were amplified by reverse transcriptase-nested polymerase chain reaction (RT-nested PCR). Ten of the 2104 adult ticks (0.4%) and two of the 356 nymph ticks (0.2%) were positive for the envelope (E) gene of TBEV. Twelve TBEV RNA-positive samples were detected in Gyeonggi and Gangwon provinces. Phylogenetic analysis showed that the E genes of the TBEV isolates were clustered with the Western European subtype (98% identity). This study suggests that TBEVs may exist in Korea.

  10. Connectivity and conditional models of access and abundance of species in stream networks.

    PubMed

    Chelgren, Nathan D; Dunham, Jason B

    2015-07-01

    Barriers to passage of aquatic organisms at stream road crossings are a major cause of habitat fragmentation in stream networks. Accordingly, large investments have been made to restore passage at these crossings, but often without estimation of population-level benefits. Here, we describe a broad-scale approach to quantifying the effectiveness of passage restoration in terms interpretable at population levels, namely numbers of fish and length of stream gained through restoration, by sampling abundance in a study design that accounts for variable biogeographic species pools, variable stream and barrier configurations, and variable probabilities of capture and detectability for multiple species. We modified an existing zero-inflated negative-binomial model to estimate the probability of site access, abundance conditional on access, and capture probability of individual fish. Therein, we modeled probability of access as a function of gradient, stream road-crossing type, and downstream access by fish simultaneously with a predictive model for abundance at sites accessible to fish. Results indicated that replacement of barriers with new crossing designs intended to allow for greater movement was associated with dramatically higher probability of access for all fishes, including migratory Pacific salmon, trout, sculpin, and lamprey. Conversely, existing non-replaced crossings negatively impacted fish distributions. Assuming no downstream constraints on access, we estimated the potential length of stream restored by the program ranged between 7.33 (lamprey) and 15.28 km (small coastal cutthroat and rainbow trout). These contributions represented a fraction of the total length available upstream (187 km) of replaced crossings. When limited ranges of species were considered, the estimated contributions of culvert replacement were reduced (1.65-km range, for longnose dace to 12.31 km for small coastal cutthroat and rainbow trout). Numbers of fish contributed ranged from

  11. Borrelia Diversity and Co-infection with Other Tick Borne Pathogens in Ticks

    PubMed Central

    Raileanu, Cristian; Moutailler, Sara; Pavel, Ionuţ; Porea, Daniela; Mihalca, Andrei D.; Savuta, Gheorghe; Vayssier-Taussat, Muriel

    2017-01-01

    Identifying Borrelia burgdorferi as the causative agent of Lyme disease in 1981 was a watershed moment in understanding the major impact that tick-borne zoonoses can have on public health worldwide, particularly in Europe and the USA. The medical importance of tick-borne diseases has long since been acknowledged, yet little is known regarding the occurrence of emerging tick-borne pathogens such as Borrelia spp., Anaplasma phagocytophilum, Rickettsia spp., Bartonella spp., “Candidatus Neoehrlichia mikurensis”, and tick-borne encephalitis virus in questing ticks in Romania, a gateway into Europe. The objective of our study was to identify the infection and co-infection rates of different Borrelia genospecies along with other tick-borne pathogens in questing ticks collected from three geographically distinct areas in eastern Romania. We collected 557 questing adult and nymph ticks of three different species (534 Ixodes ricinus, 19 Haemaphysalis punctata, and 4 Dermacentor reticulatus) from three areas in Romania. We analyzed ticks individually for the presence of eight different Borrelia genospecies with high-throughput real-time PCR. Ticks with Borrelia were then tested for possible co-infections with A. phagocytophilum, Rickettsia spp., Bartonella spp., “Candidatus Neoehrlichia mikurensis”, and tick-borne encephalitis virus. Borrelia spp. was detected in I. ricinus ticks from all sampling areas, with global prevalence rates of 25.8%. All eight Borrelia genospecies were detected in I. ricinus ticks: Borrelia garinii (14.8%), B. afzelii (8.8%), B. valaisiana (5.1%), B. lusitaniae (4.9%), B. miyamotoi (0.9%), B. burgdorferi s.s (0.4%), and B. bissettii (0.2%). Regarding pathogen co-infection 64.5% of infected I. ricinus were positive for more than one pathogen. Associations between different Borrelia genospecies were detected in 9.7% of ticks, and 6.9% of I. ricinus ticks tested positive for co-infection of Borrelia spp. with other tick-borne pathogens. The

  12. MESSENGER Searches for Less Abundant or Weakly Emitting Species in Mercury's Exosphere

    NASA Technical Reports Server (NTRS)

    Vervack, Ronald J., Jr.; McClintock, William E.; Killen, Rosemary M.; Sprague, Ann L.; Burger, Matthew H.; Merkel, Aimee W.; Sarantos, Menelaos

    2011-01-01

    Mercury's exosphere is composed of material that originates at the planet's surface, whether that material is native or delivered by the solar wind and micrometeoroids. Many exospheric species have been detected by remote sensing, including H and He by Mariner 10, Na, K, and Ca by ground-based observations, and H, Na, Ca, Mg, and Ca+ by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft. Other exospheric species, including Fe, AI, Si, 0, S, Mn, CI, Ti, OH, and their ions, are expected to be present on the basis of MESSENGER surface measurements and models of Mercury's surface chemistry. Here we report on searches for these species made with the Ultraviolet and Visible Spectrometer (UVVS) channel of the Mercury Atmospheric and Surface Composition Spectrometer (MASCS). No obvious signatures of the listed species have yet been observed in Mercury's exosphere by the UVVS as of this writing. It is possible that detections are elusive because the optimum regions of the exosphere have not been sampled. The Sun-avoidance constraints on MESSENGER place tight limits on instrument boresight directions, and some regions are probed infrequently. If there are strong spatial gradients in the distribution of weakly emitting species, a high-resolution sampling of specific regions may be required to detect them. Summing spectra over time will also aid in the ability to detect weaker emission. Observations to date nonetheless permit strong upper limits to be placed on the abundances of many undetected species, in some cases as functions of time and space. As those limits are lowered with time, the absence of detections can provide insight into surface composition and the potential source mechanisms of exospheric material.

  13. A spotted fever group Rickettsia from an exotic tick species, Amblyomma exornatum (Acari: Ixodidae), in a reptile breeding facility in the United States.

    PubMed

    Reeves, Will K; Durden, Lance A; Dasch, Gregory A

    2006-09-01

    Adults and nymphs of Amblyomma exornatum Koch (Acari: Ixodidae), an exotic African tick of monitor lizards, were collected from a Gray's monitor lizard, Varanus olivaceus Hallowell, that died in a reptile facility in Alabama. Nine adult ticks were tested by polymerase chain reaction for rickettsial agents. DNA from a novel spotted fever group Rickettsia was amplified and sequenced from one of the nine ticks. The novel Rickettsia was most similar to "Rickettsia anan," which is associated with Amblyomma from Asia. The detection of a spotted fever group Rickettsia in exotic ticks emphasizes the potential threat posed by the importation and propagation of exotic animals in the United States.

  14. Prevalence of tick-borne pathogens in ticks collected from migratory birds in Latvia.

    PubMed

    Capligina, Valentina; Salmane, Ineta; Keišs, Oskars; Vilks, Karlis; Japina, Kristine; Baumanis, Viesturs; Ranka, Renate

    2014-02-01

    Migratory birds act as hosts and long-distance vectors for several tick-borne infectious agents. Here, feeding Ixodes ticks were collected from migratory birds during the autumn migration period in Latvia and screened for the presence of epidemiologically important non-viral pathogens. A total of 93 DNA samples of ticks (37 larvae and 56 nymphs) removed from 41 birds (order Passeriformes, 9 species) was tested for Lyme borreliosis spirochaetes, Anaplasma phagocytophilum, Rickettsia spp., and Babesia spp. Borrelia burgdorferi DNA was detected in 18% of the tick samples, and a majority of infected ticks were from thrush (Turdus spp.) birds. Among the infected ticks, Borrelia valaisiana was detected in 41% of cases, Borrelia garinii in 35%, and mixed Bo. valaisiana and Bo. garinii infection in 24%. Anaplasma phagocytophilum DNA was detected in 2% of ticks, R. helvetica in 12%, and Babesia spp. pathogens in 4% of ticks. Among these samples, 3 Babesia species were identified: Ba. divergens, Ba. microti, and Ba. venatorum. Coinfection with different pathogens that included mixed infections with different Borrelia genospecies was found in 20% of nymphal and 3% of larval Ixodes ticks. These results suggest that migratory birds may support the circulation and spread of medically significant zoonoses in Europe.

  15. Macroinvertebrate abundance, water chemistry, and wetland characteristics affect use of wetlands by avian species in Maine

    USGS Publications Warehouse

    Longcore, J.R.; McAuley, D.G.; Pendelton, G.W.; Bennatti, C.R.; Mingo, T.M.; Stromborg, K.L.

    2006-01-01

    Our objective was to determine use by avian species (e.g., piscivores, marsh birds, waterfowl, selected passerines) of 29 wetlands in areas with low (<200 μeq l−1) acid-neutralizing capacity (ANC) in southeastern Maine. We documented bird, pair, and brood use during 1982–1984 and in 1982 we sampled 10 wetlands with a sweep net to collect invertebrates. We related mean numbers of invertebrates per wetland to water chemistry, basin characteristics, and avian use of different wetland types. Shallow, beaver (Castor canadensis)-created wetlands with the highest phosphorus levels and abundant and varied macrophyte assemblages supported greater densities of macroinvertebrates and numbers of duck broods (88.3% of all broods) in contrast to deep, glacial type wetlands with sparse vegetation and lower invertebrate densities that supported fewer broods (11.7%). Low pH may have affected some acid-intolerant invertebrate taxa (i.e., Ephemeroptera), but high mean numbers of Insecta per wetland were recorded from wetlands with a pH of 5.51. Other Classes and Orders of invertebrates were more abundant on wetlands with pH > 5.51. All years combined use of wetlands by broods was greater on wetlands with pH ≤ 5.51 (77.4%) in contract to wetlands with pH > 5.51 that supported 21.8% of the broods. High mean brood density was associated with mean number of Insecta per wetland. For lentic wetlands created by beaver, those habitats contained vegetative structure and nutrients necessary to provide cover to support invertebrate populations that are prey of omnivore and insectivore species. The fishless status of a few wetlands may have affected use by some waterfowl species and obligate piscivores.

  16. Relative Abundance of Oligosaccharides in Candida Species as Determined by Fluorophore-Assisted Carbohydrate Electrophoresis

    PubMed Central

    Goins, Tresa L.; Cutler, Jim E.

    2000-01-01

    Fluorophore-assisted carbohydrate electrophoresis (FACE) is a straightforward, sensitive method for determining the presence and relative abundance of individual oligomannosyl residues in Candida mannoprotein, the major antigenic determinant located on the outer surface of the yeast cell wall. The single terminal aldehydes of oligomannosyl residues released by hydrolysis were tagged with the charged fluorophore 8-aminonaphthalene-1,3,6-trisulfonate (ANTS) and separated with high resolution on the basis of size by polyacrylamide gel electrophoresis. ANTS fluorescence labeling was not biased by oligomannoside length; therefore, band fluorescence intensity was directly related to the relative abundance of individual oligomannoside moieties in heterogeneous samples. FACE analysis revealed the major oligomannosides released by acid hydrolysis and β-elimination of Fehling-precipitated mannan from Candida albicans, which were the same as those previously reported in studies based on mass and nuclear magnetic spectroscopic analysis. FACE was also amenable to the analysis of samples obtained by direct hydrolysis of whole yeast cells. Whole-cell acid hydrolysis and whole-cell β-elimination of two isolates each of C. albicans, C. glabrata, C. krusei, C. lusitaniae, C. parapsilosis, C. rugosa, C. stellatoidea, and C. tropicalis resulted in oligomannoside gel banding patterns that were species and strain specific for the 16 isolates surveyed. Whereas some bands were specific for an individual isolate or species, other bands were shared by two or three species in various groupings. Differences in the mannoprotein composition of C. albicans A9 and four spontaneous cell surface mutants were also detected. Mannan “fingerprints,” or banding pattern profiles, derived from the electrophoretic mobilities of individual bands relative to the migration of acid-hydrolyzed dextran (relative migration index) yielded profiles characteristic of individual isolates not revealed by

  17. An insight into the proteome of the saliva of the argasid tick Ornithodoros moubata reveals important differences in saliva protein composition between the sexes.

    PubMed

    Díaz-Martín, Verónica; Manzano-Román, Raúl; Valero, Luz; Oleaga, Ana; Encinas-Grandes, Antonio; Pérez-Sánchez, Ricardo

    2013-03-27

    Tick saliva contains pharmacologically active molecules that allow these parasites to obtain a blood meal from the host and facilitate host infection by tick-borne pathogens. Recent transcriptomic and proteomic analyses of the salivary glands of several tick species have provided data sets that are invaluable for a better understanding of tick sialomes and tick-host-pathogen relationships. Here we performed a proteomic study of the saliva from the argasid tick Ornithodoros moubata. Saliva samples from female and male specimens were analyzed separately by LC-MS/MS before and after their equalization to facilitate the identification of the less abundant proteins. We report the array of 193 proteins identified in the saliva of O. moubata showing: (i) the broad and complex composition of the saliva of this tick, in good agreement with the complexity of the argasid and ixodid sialomes described previously; (ii) a notable difference in the saliva proteomes of females and males, since only 10 of the proteins identified appeared to be shared by both sexes; and (iii) the presence in the salivary fluid of a wide range of proteins known to be housekeeping/intracellular, which could be secreted in unconventional ways, including exosome secretion.

  18. Molecular analysis of microbial communities identified in different developmental stages of Ixodes scapularis ticks from Westchester and Dutchess Counties, New York.

    PubMed

    Moreno, Claudia X; Moy, Fred; Daniels, Thomas J; Godfrey, Henry P; Cabello, Felipe C

    2006-05-01

    Ixodes scapularis ticks play an important role in the transmission of a wide variety of pathogens between various mammalian species, including humans. Pathogens transmitted by ticks include Borrelia, Anaplasma and Babesia. Although ticks may harbour both pathogenic and non-pathogenic microflora, little is known about how the diversity of the microflora within ticks may influence the transmission of pathogens. To begin addressing this question, we examined the composition of bacterial communities present in Ixodes scapularis collected from Westchester and Dutchess Counties, New York State, at different developmental and nutritional stages. Genetic fingerprints of bacterial populations were generated by temporal temperature gradient gel electrophoresis (TTGE) separation of individual polymerase chain reaction (PCR)-amplified 16S rRNA gene fragments, followed by DNA sequence analysis for bacterial identification. The fingerprints of the TTGE bands were grouped into five clusters. The most abundant DNA sequence found in all the samples was Rickettsia, followed by Pseudomonas and Borrelia. Ralstonia, Anaplasma, Enterobacterias, Moraxella, Rhodococcus and uncultured proteobacterium were present as well. We also determined the prevalence of Anaplasma phagocytophilum and Borrelia burgdorferi by PCR and DNA sequence analysis. Statistical analyses indicated significant variations in the bacterial communities depending on tick developmental stage and degree of engorgement. We suggest that these two elements affect microbial diversity within the tick and may in turn influence pathogen transmission to humans and animals after tick bite.

  19. Avian Migrants Facilitate Invasions of Neotropical Ticks and Tick-Borne Pathogens into the United States

    PubMed Central

    Auckland, Lisa D.; Marra, Peter P.

    2015-01-01

    Migratory birds have the potential to transport exotic vectors and pathogens of human and animal health importance across vast distances. We systematically examined birds that recently migrated to the United States from the Neotropics for ticks. We screened both ticks and birds for tick-borne pathogens, including Rickettsia species and Borrelia burgdorferi. Over two spring seasons (2013 and 2014), 3.56% of birds (n = 3,844) representing 42.35% of the species examined (n = 85) were infested by ticks. Ground-foraging birds with reduced fuel stores were most commonly infested. Eight tick species were identified, including seven in the genus Amblyomma, of which only Amblyomma maculatum/Amblyomma triste is known to be established in the United States. Most ticks on birds (67%) were neotropical species with ranges in Central and South America. Additionally, a single Ixodes genus tick was detected. A total of 29% of the ticks (n = 137) and no avian blood samples (n = 100) were positive for infection with Rickettsia species, including Rickettsia parkeri, an emerging cause of spotted fever in humans in the southern United States, a species in the group of Rickettsia monacensis, and uncharacterized species and endosymbionts of unknown pathogenicity. No avian tick or blood samples tested positive for B. burgdorferi, the etiologic agent of Lyme disease. An extrapolation of our findings suggests that anywhere from 4 to 39 million exotic neotropical ticks are transported to the United States annually on migratory songbirds, with uncertain consequences for human and animal health if the current barriers to their establishment and spread are overcome. PMID:26431964

  20. Avian migrants facilitate invasions of neotropical ticks and tick-borne pathogens into the United States.

    PubMed

    Cohen, Emily B; Auckland, Lisa D; Marra, Peter P; Hamer, Sarah A

    2015-12-01

    Migratory birds have the potential to transport exotic vectors and pathogens of human and animal health importance across vast distances. We systematically examined birds that recently migrated to the United States from the Neotropics for ticks. We screened both ticks and birds for tick-borne pathogens, including Rickettsia species and Borrelia burgdorferi. Over two spring seasons (2013 and 2014), 3.56% of birds (n = 3,844) representing 42.35% of the species examined (n = 85) were infested by ticks. Ground-foraging birds with reduced fuel stores were most commonly infested. Eight tick species were identified, including seven in the genus Amblyomma, of which only Amblyomma maculatum/Amblyomma triste is known to be established in the United States. Most ticks on birds (67%) were neotropical species with ranges in Central and South America. Additionally, a single Ixodes genus tick was detected. A total of 29% of the ticks (n = 137) and no avian blood samples (n = 100) were positive for infection with Rickettsia species, including Rickettsia parkeri, an emerging cause of spotted fever in humans in the southern United States, a species in the group of Rickettsia monacensis, and uncharacterized species and endosymbionts of unknown pathogenicity. No avian tick or blood samples tested positive for B. burgdorferi, the etiologic agent of Lyme disease. An extrapolation of our findings suggests that anywhere from 4 to 39 million exotic neotropical ticks are transported to the United States annually on migratory songbirds, with uncertain consequences for human and animal health if the current barriers to their establishment and spread are overcome.

  1. Tick infestation in birds and prevalence of pathogens in ticks collected from different places in Germany.

    PubMed

    Klaus, Christine; Gethmann, Jörn; Hoffmann, Bernd; Ziegler, Ute; Heller, Martin; Beer, Martin

    2016-07-01

    The importance of ticks and tick-borne pathogens for human and animal health has been increasing over the past decades. For their transportation and dissemination, birds may play a more important role than wingless hosts. In this study, tick infestation of birds in Germany was examined. Eight hundred ninety-two captured birds were infested with ticks and belonged to 48 different species, of which blackbirds (Turdus merula) and song thrushes (Turdus philomelos) were most strongly infested. Ground feeders were more strongly infested than non-ground feeders, sedentary birds more strongly than migratory birds, and short-distance migratory birds more strongly than long-distance migratory birds. Mean tick infestation per bird ranged between 2 (long-distance migratory bird) and 4.7 (sedentary bird), in some single cases up to 55 ticks per bird were found. With the exception of three nymphs of Haemaphysalis spp., all ticks belonged to Ixodes spp., the most frequently detected tick species was Ixodes ricinus. Birds were mostly infested by nymphs (65.1 %), followed by larvae (32.96 %). Additionally, ticks collected from birds were examined for several pathogens: Tick-borne encephalitis virus (TBEV) and Sindbisvirus with real-time RT-PCR, Flaviviruses, Simbuviruses and Lyssaviruses with broad-range standard RT-PCR-assays, and Borrelia spp. with a Pan-Borrelia real-time PCR. Interestingly, no viral pathogens could be detected, but Borrelia spp. positive ticks were collected from 76 birds. Borrelia (B.) garinii, B. valaisiaina, B. burgdorferi s.s. and B. afzelii were determined. The screening of ticks and birds for viral pathogens with broad range PCR-assays was tested and the use as an "early warning system" is discussed.

  2. A serological survey of tick-borne pathogens in dogs in North America and the Caribbean as assessed by Anaplasma phagocytophilum, A. platys, Ehrlichia canis, E. chaffeensis, E. ewingii, and Borrelia burgdorferi species-specific peptides

    PubMed Central

    Qurollo, Barbara A.; Chandrashekar, Ramaswamy; Hegarty, Barbara C.; Beall, Melissa J.; Stillman, Brett A.; Liu, Jiayou; Thatcher, Brendon; Pultorak, Elizabeth; Cerrito, Brian; Walsh, Mary; Breitschwerdt, Edward B.

    2014-01-01

    Introduction Tick-borne pathogens cause a spectrum of disease manifestations in both dogs and humans. Recognizing regional and temporal shifts in exposure are important as tick distributions change. To better delineate regional exposure to canine tick-borne pathogens, an expanded set of species-specific peptides were used to detect Anaplasma phagocytophilum (Aph), Anaplasma platys (Apl), Ehrlichia canis (Ec), Ehrlichia chaffeensis (Ech), Ehrlichia ewingii (Eew), and Borrelia burgdorferi (Bb) antibodies in canine serum. Methods Archived canine serum samples (n=6,582) collected during 2008–2010 and in 2012 from the US, Canada, and the Caribbean were retrospectively screened for antibodies against Ehrlichia and Anaplasma species-specific peptides. Overall, regional and temporal seroprevalence rates were determined. Results Overall Bb and Eew were the most seroprevalent pathogens. During 2008–2010, seroprevalence rates increased overall for Aph and Ech, and regionally, Bb and Aph seroprevalence rates increased in the South. Canada had unexpectedly high seroprevalence rates for Ec and Apl. The most common co-exposures were Eew+Ech, followed by Aph+Bb and Eew+Bb. Conclusions This study demonstrated significant shifts in canine vector-borne disease seroprevalence rates. The use of specific peptides facilitated improved geographic delineation of tick-borne pathogen distributions among dogs, which may enhance epidemiological surveillance of vector-borne pathogens shared by dogs and humans. PMID:25405006

  3. Virus investigation in ticks from migratory birds in Italy.

    PubMed

    Mancini, Fabiola; Toma, Luciano; Ciervo, Alessandra; Di Luca, Marco; Faggioni, Giovanni; Lista, Forigio; Rezza, Giovanni

    2013-10-01

    The role of migratory birds in circulation tick-borne viruses needs to be better defined. In order to assess the potential role of migratory birds in exotic virus spread, we conducted a study to identify ticks collected from migratory birds in the Central Region of Italy, and performed molecular investigation for Crimea-Congo Hemorrhagic Fever (CCHFV), West Nile fever (WNFV) and Usutu (USUV) in the vectors. A total of 137 competent ticks were collected with predominance of Hyalomma species. Although, negative results were obtained for all viruses considered, the high proportion of Hyalomma ticks highlights the potential risk for the dissemination of tick-borne viruses through infested migratory birds.

  4. The tick (Acari: Ixodidae) fauna of Herald's Beacon Islet, Australia.

    PubMed

    Kwak, Mackenzie L; Mintram, Kate

    2017-01-01

    A rare opportunity to travel to Herald's Beacon Islet with permission from the Australian government to collect ticks allowed for a survey of the tick fauna of the island to be undertaken for the first time. The avian fauna of the island, which serve as hosts, was also recorded and includes one new species record for the island. The seabird soft tick Ornithodoros capensis Neumann and the seabird hard tick Amblyomma loculosum Neumann were found to be present on the island. Images of the ticks present on the island are presented along with morphological characters for their identification.

  5. Bacteria of the genus Rickettsia in ticks (Acari: Ixodidae) collected from birds in Costa Rica.

    PubMed

    Ogrzewalska, Maria; Literák, Ivan; Capek, Miroslav; Sychra, Oldřich; Calderón, Víctor Álvarez; Rodríguez, Bernardo Calvo; Prudencio, Carlos; Martins, Thiago F; Labruna, Marcelo B

    2015-06-01

    The aim of this study was to document the presence of Rickettsia spp. in ticks parasitizing wild birds in Costa Rica. Birds were trapped at seven locations in Costa Rica during 2004, 2009, and 2010; then visually examined for the presence of ticks. Ticks were identified, and part of them was tested individually for the presence of Rickettsia spp. by polymerase chain reaction (PCR) using primers targeting fragments of the rickettsial genes gltA and ompA. PCR products were DNA-sequenced and analyzed in BLAST to determine similarities with previously reported rickettsial agents. A total of 1878 birds were examined, from which 163 birds (9%) were infested with 388 ticks of the genera Amblyomma and Ixodes. The following Amblyomma (in decreasing order of abundance) were found in immature stages (larvae and nymphs): Amblyomma longirostre, Amblyomma calcaratum, Amblyomma coelebs, Amblyomma sabanerae, Amblyomma varium, Amblyomma maculatum, and Amblyomma ovale. Ixodes ticks were represented by Ixodes minor and two unclassified species, designated here as Ixodes sp. genotype I, and Ixodes sp. genotype II. Twelve of 24 tested A. longirostre ticks were found to be infected with 'Candidatus Rickettsia amblyommii', and 2 of 4 A. sabanerae were found to be infected with Rickettsia bellii. Eight of 10 larval Ixodes minor were infected with an endosymbiont (a novel Rickettsia sp. agent) genetically related to the Ixodes scapularis endosymbiont. No rickettsial DNA was found in A. calcaratum, A. coelebs, A. maculatum, A. ovale, A. varium, Ixodes sp. I, and Ixodes sp. II. We report the occurrence of I. minor in Costa Rica for the first time and a number of new bird host-tick associations. Moreover, 'Candidatus R. amblyommii' and R. bellii were found in A. longirostre and A. sabanerae, respectively, in Costa Rica for the first time.

  6. Plant community responses to long-term fertilization: changes in functional group abundance drive changes in species richness.

    PubMed

    Dickson, Timothy L; Gross, Katherine L

    2013-12-01

    Declines in species richness due to fertilization are typically rapid and associated with increases in aboveground production. However, in a long-term experiment examining the impacts of fertilization in an early successional community, we found it took 14 years for plant species richness to significantly decline in fertilized plots, despite fertilization causing a rapid increase in aboveground production. To determine what accounted for this lag in the species richness response, we examined several potential mechanisms. We found evidence suggesting the abundance of one functional group-tall species with long-distance (runner) clonality-drove changes in species richness, and we found little support for other mechanisms. Tall runner species initially increased in abundance due to fertilization, then declined dramatically and were not abundant again until later in the experiment, when species richness and the combined biomass of all other functional groups (non-tall runner) declined. Over 86 % of the species found throughout the course of our study are non-tall runner, and there is a strong negative relationship between non-tall runner and tall runner biomass. We therefore suggest that declines in species richness in the fertilized treatment are due to high tall runner abundance that decreases the abundance and richness of non-tall runner species. By identifying the functional group that drives declines in richness due to fertilization, our results help to elucidate how fertilization decreases plant richness and also suggest that declines in richness due to fertilization can be lessened by controlling the abundance of species with a tall runner growth form.

  7. Soft tick sampling and collection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several soft tick species in the genus Ornithodoros are vectors of African swine fever virus (ASFV) in nature, or known to be susceptible to infection. African swine fever (ASF) caused by ASFV is considered one of the most serious transboundary swine diseases because of its high lethality for pigs, ...

  8. Ticks and tick-borne pathogens at the cutaneous interface: host defenses, tick countermeasures, and a suitable environment for pathogen establishment

    PubMed Central

    Wikel, Stephen

    2013-01-01

    Ticks are unique among hematophagous arthropods by continuous attachment to host skin and blood feeding for days; complexity and diversity of biologically active molecules differentially expressed in saliva of tick species; their ability to modulate the host defenses of pain and itch, hemostasis, inflammation, innate and adaptive immunity, and wound healing; and, the diverse array of infectious agents they transmit. All of these interactions occur at the cutaneous interface in a complex sequence of carefully choreographed host defense responses and tick countermeasures resulting in an environment that facilitates successful blood feeding and establishment of tick-borne infectious agents within the host. Here, we examine diverse patterns of tick attachment to host skin, blood feeding mechanisms, salivary gland transcriptomes, bioactive molecules in tick saliva, timing of pathogen transmission, and host responses to tick bite. Ticks engage and modulate cutaneous and systemic immune defenses involving keratinocytes, natural killer cells, dendritic cells, T cell subpopulations (Th1, Th2, Th17, Treg), B cells, neutrophils, mast cells, basophils, endothelial cells, cytokines, chemokines, complement, and extracellular matrix. A framework is proposed that integrates tick induced changes of skin immune effectors with their ability to respond to tick-borne pathogens. Implications of these changes are addressed. What are the consequences of tick modulation of host cutaneous defenses? Does diversity of salivary gland transcriptomes determine differential modulation of host inflammation and immune defenses and therefore, in part, the clades of pathogens effectively transmitted by different tick species? Do ticks create an immunologically modified cutaneous environment that enhances specific pathogen establishment? Can tick saliva molecules be used to develop vaccines that block pathogen transmission? PMID:24312085

  9. Relating large-scale climate variability to local species abundance: ENSO forcing and shrimp in Breton Sound, Louisiana, USA

    USGS Publications Warehouse

    Piazza, Bryan P.; LaPeyre, Megan K.; Keim, B.D.

    2010-01-01

    Climate creates environmental constraints (filters) that affect the abundance and distribution of species. In estuaries, these constraints often result from variability in water flow properties and environmental conditions (i.e. water flow, salinity, water temperature) and can have significant effects on the abundance and distribution of commercially important nekton species. We investigated links between large-scale climate variability and juvenile brown shrimp Farfantepenaeus aztecus abundance in Breton Sound estuary, Louisiana (USA). Our goals were to (1) determine if a teleconnection exists between local juvenile brown shrimp abundance and the El Niño Southern Oscillation (ENSO) and (2) relate that linkage to environmental constraints that may affect juvenile brown shrimp recruitment to, and survival in, the estuary. Our results identified a teleconnection between winter ENSO conditions and juvenile brown shrimp abundance in Breton Sound estuary the following spring. The physical connection results from the impact of ENSO on winter weather conditions in Breton Sound (air pressure, temperature, and precipitation). Juvenile brown shrimp abundance effects lagged ENSO by 3 mo: lower than average abundances of juvenile brown shrimp were caught in springs following winter El Niño events, and higher than average abundances of brown shrimp were caught in springs following La Niña winters. Salinity was the dominant ENSO-forced environmental filter for juvenile brown shrimp. Spring salinity was cumulatively forced by winter river discharge, winter wind forcing, and spring precipitation. Thus, predicting brown shrimp abundance requires incorporating climate variability into models.

  10. Species, Abundance and Function of Ammonia-oxidizing Archaea in Inland Waters across China

    PubMed Central

    Zhou, Leiliu; Wang, Shanyun; Zou, Yuxuan; Xia, Chao; Zhu, Guibing

    2015-01-01

    Ammonia oxidation is the first step in nitrification and was thought to be performed solely by specialized bacteria. The discovery of ammonia-oxidizing archaea (AOA) changed this view. We examined the large scale and spatio-temporal occurrence, abundance and role of AOA throughout Chinese inland waters (n = 28). Molecular survey showed that AOA was ubiquitous in inland waters. The existence of AOA in extreme acidic, alkaline, hot, cold, eutrophic and oligotrophic environments expanded the tolerance limits of AOA, especially their known temperature tolerance to −25 °C, and substrate load to 42.04 mM. There were spatio-temporal divergences of AOA community structure in inland waters, and the diversity of AOA in inland water ecosystems was high with 34 observed species-level operational taxonomic units (OTUs; based on a 15% cutoff) distributed widely in group I.1b, I.1a, and I.1a-associated. The abundance of AOA was quite high (8.5 × 104 to 8.5 × 109 copies g−1), and AOA outnumbered ammonia-oxidizing bacteria (AOB) in the inland waters where little human activities were involved. On the whole AOB predominate the ammonia oxidation rate over AOA in inland water ecosystems, and AOA play an indispensable role in global nitrogen cycle considering that AOA occupy a broader habitat range than AOB, especially in extreme environments. PMID:26522086

  11. Species, Abundance and Function of Ammonia-oxidizing Archaea in Inland Waters across China

    NASA Astrophysics Data System (ADS)

    Zhou, Leiliu; Wang, Shanyun; Zou, Yuxuan; Xia, Chao; Zhu, Guibing

    2015-11-01

    Ammonia oxidation is the first step in nitrification and was thought to be performed solely by specialized bacteria. The discovery of ammonia-oxidizing archaea (AOA) changed this view. We examined the large scale and spatio-temporal occurrence, abundance and role of AOA throughout Chinese inland waters (n = 28). Molecular survey showed that AOA was ubiquitous in inland waters. The existence of AOA in extreme acidic, alkaline, hot, cold, eutrophic and oligotrophic environments expanded the tolerance limits of AOA, especially their known temperature tolerance to -25 °C, and substrate load to 42.04 mM. There were spatio-temporal divergences of AOA community structure in inland waters, and the diversity of AOA in inland water ecosystems was high with 34 observed species-level operational taxonomic units (OTUs; based on a 15% cutoff) distributed widely in group I.1b, I.1a, and I.1a-associated. The abundance of AOA was quite high (8.5 × 104 to 8.5 × 109 copies g-1), and AOA outnumbered ammonia-oxidizing bacteria (AOB) in the inland waters where little human activities were involved. On the whole AOB predominate the ammonia oxidation rate over AOA in inland water ecosystems, and AOA play an indispensable role in global nitrogen cycle considering that AOA occupy a broader habitat range than AOB, especially in extreme environments.

  12. Genetic characterization of tick-borne flaviviruses: new insights into evolution, pathogenetic determinants and taxonomy.

    PubMed

    Grard, Gilda; Moureau, Grégory; Charrel, Rémi N; Lemasson, Jean-Jacques; Gonzalez, Jean-Paul; Gallian, Pierre; Gritsun, Tamara S; Holmes, Edward C; Gould, Ernest A; de Lamballerie, Xavier

    2007-04-25

    Here, we analyze the complete coding sequences of all recognized tick-borne flavivirus species, including Gadgets Gully, Royal Farm and Karshi virus, seabird-associated flaviviruses, Kadam virus and previously uncharacterized isolates of Kyasanur Forest disease virus and Omsk hemorrhagic fever virus. Significant taxonomic improvements are proposed, e.g. the identification of three major groups (mammalian, seabird and Kadam tick-borne flavivirus groups), the creation of a new species (Karshi virus) and the assignment of Tick-borne encephalitis and Louping ill viruses to a unique species (Tick-borne encephalitis virus) including four viral types (i.e. Western Tick-borne encephalitis virus, Eastern Tick-borne encephalitis virus, Turkish sheep Tick-borne encephalitis virus and Louping ill Tick-borne encephalitis virus). The analyses also suggest a complex relationship between viruses infecting birds and those infecting mammals. Ticks that feed on both categories of vertebrates may constitute the evolutionary bridge between the three distinct identified lineages.

  13. [Lyme disease: prophylaxis after tick bite].

    PubMed

    Patey, O

    2007-01-01

    Lyme disease is a bacterial infection caused by Borrelia burgdorferi, which is transmitted by infected ticks. The transmission depends on several factors, especially on the duration of the tick's presence in the host body (the nymph which is smaller than the adults and thus less visible, is in this case the most frequently involved) and on whether the tick is infected or not. The interpretation of results in the few available studies is made difficult by the lack of information obtained (due to difficulty to collect information and examination costs). The comparison is made even more difficult by the difference between Borrelia ticks species in various regions. Today, the best methods are preventive: protective clothing, tick repellents, checking and removal of ticks after a journey in an endemic zone, and in case of tick bite, regular examination of the bite site during the following weeks in order to initiate an early curative treatment if ECM is diagnosed. The currently available data seems to be insufficient to suggest systematic antimicrobial prophylaxis in case of tick bite.

  14. Modelling the Abundances of Two Major Culicoides (Diptera: Ceratopogonidae) Species in the Niayes Area of Senegal.

    PubMed

    Diarra, Maryam; Fall, Moussa; Lancelot, Renaud; Diop, Aliou; Fall, Assane G; Dicko, Ahmadou; Seck, Momar Talla; Garros, Claire; Allène, Xavier; Rakotoarivony, Ignace; Bakhoum, Mame Thierno; Bouyer, Jérémy; Guis, Hélène

    2015-01-01

    In Senegal, considerable mortality in the equine population and hence major economic losses were caused by the African horse sickness (AHS) epizootic in 2007. Culicoides oxystoma and Culicoides imicola, known or suspected of being vectors of bluetongue and AHS viruses are two predominant species in the vicinity of horses and are present all year-round in Niayes area, Senegal. The aim of this study was to better understand the environmental and climatic drivers of the dynamics of these two species. Culicoides collections were obtained using OVI (Onderstepoort Veterinary Institute) light traps at each of the 5 sites for three nights of consecutive collection per month over one year. Cross Correlation Map analysis was performed to determine the time-lags for which environmental variables and abundance data were the most correlated. C. oxystoma and C. imicola count data were highly variable and overdispersed. Despite modelling large Culicoides counts (over 220,000 Culicoides captured in 354 night-traps), using on-site climate measures, overdispersion persisted in Poisson, negative binomial, Poisson regression mixed-effect with random effect at the site of capture models. The only model able to take into account overdispersion was the Poisson regression mixed-effect model with nested random effects at the site and date of capture levels. According to this model, meteorological variables that contribute to explaining the dynamics of C. oxystoma and C. imicola abundances were: mean temperature and relative humidity of the capture day, mean humidity between 21 and 19 days prior a capture event, density of ruminants, percentage cover of water bodies within a 2 km radius and interaction between temperature and humidity for C. oxystoma; mean rainfall and NDVI of the capture day and percentage cover of water bodies for C. imicola. Other variables such as soil moisture, wind speed, degree days, land cover or landscape metrics could be tested to improve the models. Further work

  15. First report of Rickettsia raoultii in field collected Dermacentor reticulatus ticks from Austria.

    PubMed

    Duscher, Georg G; Hodžić, Adnan; Weiler, Martin; Vaux, Alexander G C; Rudolf, Ivo; Sixl, Wolfdieter; Medlock, Jolyon M; Versteirt, Veerle; Hubálek, Zdenek

    2016-07-01

    In a set of pooled field collected Dermacentor reticulatus ticks, Rickettsia raoultii, the causative agent of Tick-borne lymphadenopathy/Dermacentor-borne necrosis erythema and lymphadenopathy, was found for the first time in Austria. The coordinates of the positive locations for tick and pathogen abundance are given and shown in a map.

  16. Species richness and relative abundance of breeding birds in forests of the Mississippi Alluvial Valley

    USGS Publications Warehouse

    Nelms, C.O.; Twedt, D.J.; Smith, Winston Paul

    1993-01-01

    In 1992, the Vicksburg Field Research Station of the National Wetlands Research Center initiated research on the ecology of migratory birds within forests of the Mississippi Alluvial Valley (MAV). The MAV was historically a nearly contiguous bottomland hardwood forest, however, only remnants remain. These remnants are fragmented and often influenced by drainage projects, silviculture, agriculture, and urban development. Our objectives are to assess species richness and relative abundance, and to relate these to the size, quality, and composition of forest stands. Species richness and relative abundance were estimated for 53 randomly selected forest sites using 1 to 8 point counts per site, depending on the size of the forest fragment. However, statistical comparisons among sites will be restricted to an equal number ofpoint counts within the sites being compared. Point counts, lasting five minutes, were conducted from 11 May to 29 June 1992, foltowing Ralph, Sauer, and Droege (Point Count Standards; memo dated 9 March 1992). Vegetation was measured at the first three points on each site using a modification of the methods employed by Martin and Roper (Condor 90: 5 1-57; 1988). During 252 counts, 7 1 species were encountered, but only 62 species were encountered within a 50-m radius of point center. The mean number of species encountered within 50 m of a point, was 7.3 (s.d. = 2.7) and the mean number of individuals was 11.2 (s.d. = 4.2). The mean number of species detected at any distance was 9.6 (s.d, = 2.8) and the mean number of individuals was 15.6 (s.d. = 7.9). The most frequently encountered warblers in the MAV were Prothonotary Warbler and Northern Parula. Rarely encountered warblers were American Redstart and Worm-eating Warbler. The genera, Quercus, Ulmus, Carya, and Celtis were each encountered at 80 or more of the 152 points at which vegetation was sampled. Species most frequentlyencountered were: sugarberry (Celtis laevagata), water hickory (Caqa

  17. LogCauchy, log-sech and lognormal distributions of species abundances in forest communities

    USGS Publications Warehouse

    Yin, Z.-Y.; Peng, S.-L.; Ren, H.; Guo, Q.; Chen, Z.-H.

    2005-01-01

    Species-abundance (SA) pattern is one of the most fundamental aspects of biological community structure, providing important information regarding species richness, species-area relation and succession. To better describe the SA distribution (SAD) in a community, based on the widely used lognormal (LN) distribution model with exp(-x2) roll-off on Preston's octave scale, this study proposed two additional models, logCauchy (LC) and log-sech (LS), respectively with roll-offs of simple x-2 and e-x. The estimation of the theoretical total number of species in the whole community, S*, including very rare species not yet collected in sample, was derived from the left-truncation of each distribution. We fitted these three models by Levenberg-Marquardt nonlinear regression and measured the model fit to the data using coefficient of determination of regression, parameters' t-test and distribution's Kolmogorov-Smirnov (KS) test. Examining the SA data from six forest communities (five in lower subtropics and one in tropics), we found that: (1) on a log scale, all three models that are bell-shaped and left-truncated statistically adequately fitted the observed SADs, and the LC and LS did better than the LN; (2) from each model and for each community the S* values estimated by the integral and summation methods were almost equal, allowing us to estimate S* using a simple integral formula and to estimate its asymptotic confidence internals by regression of a transformed model containing it; (3) following the order of LC, LS, and LN, the fitted distributions became lower in the peak, less concave in the side, and shorter in the tail, and overall the LC tended to overestimate, the LN tended to underestimate, while the LS was intermediate but slightly tended to underestimate, the observed SADs (particularly the number of common species in the right tail); (4) the six communities had some similar structural properties such as following similar distribution models, having a common

  18. Coendangered hard-ticks: threatened or threatening?

    PubMed Central

    2011-01-01

    The overwhelming majority of animal conservation projects are focused on vertebrates, despite most of the species on Earth being invertebrates. Estimates state that about half of all named species of invertebrates are parasitic in at least one stage of their development. The dilemma of viewing parasites as biodiversity or pest has been discussed by several authors. However, ticks were omitted. The latest taxonomic synopses of non-fossil Ixodidae consider valid 700 species. Though, how many of them are still extant is almost impossible to tell, as many of them are known only from type specimens in museums and were never collected since their original description. Moreover, many hosts are endangered and as part of conservation efforts of threatened vertebrates, a common practice is the removal of, and treatment for external parasites, with devastating impact on tick populations. There are several known cases when the host became extinct with subsequent coextinction of their ectoparasites. For our synoptic approach we have used the IUCN status of the host in order to evaluate the status of specifically associated hard-ticks. As a result, we propose a number of 63 coendangered and one extinct hard-tick species. On the other side of the coin, the most important issue regarding tick-host associations is vectorial transmission of microbial pathogens (i.e. viruses, bacteria, protozoans). Tick-borne diseases of threatened vertebrates are sometimes fatal to their hosts. Mortality associated with pathogens acquired from ticks has been documented in several cases, mostly after translocations. Are ticks a real threat to their coendangered host and should they be eliminated? Up to date, there are no reliable proofs that ticks listed by us as coendangered are competent vectors for pathogens of endangered animals. PMID:21554736

  19. Occurrence of Ticks in Cattle in the New Pastoral Farming Areas in Rufiji District, Tanzania.

    PubMed

    Mamiro, Kamilius A; Magwisha, Henry B; Rukambile, Elpidius J; Ruheta, Martin R; Kimboka, Expery J; Malulu, Deusdedit J; Malele, Imna I

    2016-01-01

    Ticks and tick-borne diseases plus trypanosomosis are a constraint to cattle rearing in Tanzania. Rufiji district was not known for important ticks infesting cattle because inhabitants were not engaged in keeping livestock. Not only has settlement of pastoralists and cattle in Rufiji increased the number of cattle but also cattle have been the source of bringing in and spreading of ticks. This study investigated tick species that have been introduced and managed to establish themselves in the new livestock farming areas in cattle in Rufiji. Tick distribution study was undertaken in three villages of Chumbi ward seasonally in 2009, 2011, and 2012. The identified ticks were Amblyomma variegatum (56.10%), Rhipicephalus evertsi (10.25%), R. microplus (27.40%), and R. appendiculatus (6.19%) out of 12940 ticks. Results indicate that ticks are present in the new livestock settlement areas. The occurrence of ticks is correlated with the recent settlement of cattle in the district.

  20. Climatic controls on the global distribution, abundance, and species richness of mangrove forests

    USGS Publications Warehouse

    Osland, Michael J.; Feher, Laura; Griffith, Kereen; Cavanaugh, Kyle C.; Enwright, Nicholas M.; Day, Richard H.; Stagg, Camille L.; Krauss, Ken W.; Howard, Rebecca J.; Grace, James B.; Rogers, Kerrylee

    2017-01-01

    Mangrove forests are highly productive tidal saline wetland ecosystems found along sheltered tropical and subtropical coasts. Ecologists have long assumed that climatic drivers (i.e., temperature and rainfall regimes) govern the global distribution, structure, and function of mangrove forests. However, data constraints have hindered the quantification of direct climate-mangrove linkages in many parts of the world. Recently, the quality and availability of global-scale climate and mangrove data have been improving. Here, we used these data to better understand the influence of air temperature and rainfall regimes upon the distribution, abundance, and species richness of mangrove forests. Although our analyses identify global-scale relationships and thresholds, we show that the influence of climatic drivers is best characterized via regional range limit-specific analyses. We quantified climatic controls across targeted gradients in temperature and/or rainfall within 14 mangrove distributional range limits. Climatic thresholds for mangrove presence, abundance, and species richness differed among the 14 studied range limits. We identified minimum temperature-based thresholds for range limits in eastern North America, eastern Australia, New Zealand, eastern Asia, eastern South America, and southeast Africa. We identified rainfall-based thresholds for range limits in western North America, western Gulf of Mexico, western South America, western Australia, Middle East, northwest Africa, east central Africa, and west central Africa. Our results show that in certain range limits (e.g., eastern North America, western Gulf of Mexico, eastern Asia), winter air temperature extremes play an especially important role. We conclude that rainfall and temperature regimes are both important in western North America, western Gulf of Mexico, and western Australia. With climate change, alterations in temperature and rainfall regimes will affect the global distribution, abundance, and

  1. Variation in local abundance and species richness of stream fishes in relation to dispersal barriers: Implications for management and conservation

    USGS Publications Warehouse

    Nislow, K.H.; Hudy, M.; Letcher, B.H.; Smith, E.P.

    2011-01-01

    1.Barriers to immigration, all else being equal, should in principle depress local abundance and reduce local species richness. These issues are particularly relevant to stream-dwelling species when improperly designed road crossings act as barriers to migration with potential impacts on the viability of upstream populations. However, because abundance and richness are highly spatially and temporally heterogeneous and the relative importance of immigration on demography is uncertain, population- and community-level effects can be difficult to detect. 2.In this study, we tested the effects of potential barriers to upstream movements on the local abundance and species richness of a diverse assemblage of resident stream fishes in the Monongahela National Forest, West Virginia, U.S.A. Fishes were sampled using simple standard techniques above- and below road crossings that were either likely or unlikely to be barriers to upstream fish movements (based on physical dimensions of the crossing). We predicted that abundance of resident fishes would be lower in the upstream sections of streams with predicted impassable barriers, that the strength of the effect would vary among species and that variable effects on abundance would translate into lower species richness. 3.Supporting these predictions, the statistical model that best accounted for variation in abundance and species richness included a significant interaction between location (upstream or downstream of crossing) and type (passable or impassable crossing). Stream sections located above predicated impassable culverts had fewer than half the number of species and less than half the total fish abundance, while stream sections above and below passable culverts had essentially equivalent richness and abundance. 4.Our results are consistent with the importance of immigration and population connectivity to local abundance and species richness of stream fishes. In turn, these results suggest that when measured at

  2. Redescription of the female, description of the male, and several new records of Amblyomma parkeri (Acari: Ixodidae), a South American tick species.

    PubMed

    Labruna, Marcelo B; Onofrio, Valeria C; Beati, Lorenza; Arzua, Márcia; Bertola, Patricia B; Ribeiro, Alberto F; Barros-Battesti, Darci M

    2009-11-01

    The tick Amblyomma parkeri Fonseca and Aragão was described in 1952, based on female and immature ticks collected in the states of São Paulo and Santa Catarina, Brazil. Thereafter, there has been no further report of A. parkeri, and the male has remained unknown. Herein, we examined ticks collected on porcupines from a locality in the state of São Paulo. Some of the ticks were identified as Amblyomma longirostre (Koch, 1844), whereas others as A. parkeri, including male specimens, for which we provide the first description. We also provide additional reports of A. parkeri after examining collections of A. longirostre and Amblyomma geayi Neumann, 1899 from different tick collections. Morphological evidence to support the original description of A. parkeri is presented, supported by molecular analyses of portions of the 16S rRNA and 12S rRNA mitochondrial genes. Morphological particularities to separate A. parkeri, A. longirostre, and A. geayi are provided.

  3. Declines in abundance and species richness of birds following a major flood on the upper Mississippi River

    USGS Publications Warehouse

    Knutson, M.G.; Klaas, E.E.

    1997-01-01

    We examined the abundance and species richness of birds breeding in floodplain forests of the Upper Mississippi River in 1992 through 1994, and used a two-way ANOVA with repeated measures to identify effects of a 1993 flood on the bird community. Sixty-five study plots were divided into treatment and control plots based on whether they were flooded in 1993. Among 84 species observed on all plots, 41 species decreased in abundance from 1992 to 1994, 13 increased, 5 were unchanged. Sample sizes were inadequate to evaluate trends for 25 species. Species richness declined over the three-year period. Of 36 species tested with the ANOVA, 20 had a significant main effect of Year. Cool, wet conditions may have contributed to poor reproductive success in 1993, and resulted in widespread decline in floodplain bird abundance during the year following the flood. Bird abundance increased on most unflooded plots in 1993, probably because birds were displaced from flooded plots. This pattern was most striking for neotropical migrants, species preferring habitat edges, lower canopy nesters, and species that forage in the air. We suggest that periodic major flooding may maintain suitable floodplain habitat for Prothonotary Warblers (Protonotaria citrea) in the face of competition from House Wrens (Troglodytes aedon) for nest sites.

  4. Predicting recovery criteria for threatened and endangered plant species on the basis of past abundances and biological traits.

    PubMed

    Neel, Maile C; Che-Castaldo, Judy P

    2013-04-01

    Recovery plans for species listed under the U.S. Endangered Species Act are required to specify measurable criteria that can be used to determine when the species can be delisted. For the 642 listed endangered and threatened plant species that have recovery plans, we applied recursive partitioning methods to test whether the number of individuals or populations required for delisting can be predicted on the basis of distributional and biological traits, previous abundance at multiple time steps, or a combination of traits and previous abundances. We also tested listing status (threatened or endangered) and the year the recovery plan was written as predictors of recovery criteria. We analyzed separately recovery criteria that were stated as number of populations and as number of individuals (population-based and individual-based criteria, respectively). Previous abundances alone were relatively good predictors of population-based recovery criteria. Fewer populations, but a greater proportion of historically known populations, were required to delist species that had few populations at listing compared with species that had more populations at listing. Previous abundances were also good predictors of individual-based delisting criteria when models included both abundances and traits. The physiographic division in which the species occur was also a good predictor of individual-based criteria. Our results suggest managers are relying on previous abundances and patterns of decline as guidelines for setting recovery criteria. This may be justifiable in that previous abundances inform managers of the effects of both intrinsic traits and extrinsic threats that interact and determine extinction risk.

  5. Species composition and seasonal abundance of sandflies (Diptera: Psychodidae: Phlebotominae) in coffee agroecosystems.

    PubMed

    Pérez, Jeanneth; Virgen, Armando; Rojas, Julio Cesar; Rebollar-Téllez, Eduardo Alfonso; Alfredo, Castillo; Infante, Francisco; Mikery, Oscar; Marina, Carlos Felix; Ibáñez-Bernal, Sergio

    2014-02-01

    The composition and seasonal occurrence of sandflies were investigated in coffee agroecosystems in the Soconusco region of Chiapas, Mexico. Insect sampling was performed on three plantations located at different altitudes: Finca Guadalupe Zajú [1,000 m above sea level (a.s.l.)], Finca Argovia (613 m a.s.l.) and Teotihuacán del Valle (429 m a.s.l.). Sandflies were sampled monthly from August 2007-July 2008 using three sampling methods: Shannon traps, CDC miniature light traps and Disney traps. Sampling was conducted for 3 h during three consecutive nights, beginning at sunset. A total of 4,387 sandflies were collected during the course of the study: 2,718 individuals in Finca Guadalupe Zajú, 605 in Finca Argovia and 1,064 in Teotihuacán del Valle. The Shannon traps captured 94.3% of the total sandflies, while the CDC light traps and Disney traps captured 4.9% and 0.8%, respectively. More females than males were collected at all sites. While the number of sandflies captured was positively correlated with temperature and relative humidity, a negative correlation was observed between sandfly numbers and rainfall. Five species of sandflies were captured: Lutzomyia cruciata , Lutzomyia texana , Lutzomyia ovallesi , Lutzomyia cratifer / undulata and Brumptomyia sp. Lu. cruciata , constituting 98.8% of the total, was the most abundant species. None of the captured sandflies was infected with Leishmania spp.

  6. Historical abundance and morphology of Didymosphenia species in Naknek Lake, Alaska

    USGS Publications Warehouse

    Pite, D.P.; Lane, K.A.; Hermann, A.K.; Spaulding, S.A.; Finney, B.P.

    2009-01-01

    Since the 1980s, nuisance blooms of Didymosphenia geminata (Lyngbye) M. Schmidt have been documented in sites that are warmer and more mesotrophic than historical records indicate. While the invasion of D. geminata in New Zealand is well documented, it is less clear whether nuisance blooms in North America are a new phenomenon. In order to test the hypothesis that D. geminata blooms have increased in recent years, we examined the historical record of this species in sediments of Naknek Lake, in Katmai National Park, Alaska. Chronological control was established by relating the presence of two ash layers to known volcanic eruptions. We identified two species of Didymosphenia within the sediment record: D. geminata and D. clavaherculis (Ehrenberg) Metzeltin et Lange-Bertalot. This is the first published record of D. clavaherculis in North America. We found no statistically significant change in the numerical presence of D. geminata or D. clavaherculis, as a group, in Naknek Lake between the years 1218 and 2003. While there has been no sudden, or recent, increase in abundance of Didymosphenia in Naknek Lake, morphological features of D. geminata populations in Naknek Lake are distinct compared to morphological features of D. geminata in streams containing nuisance blooms from sites in North America and New Zealand. Variance in the morphology of Didymosphenia cells may help determine relationships between distinct sub-populations and establish the history of habitat invasion.

  7. Species composition and seasonal abundance of sandflies (Diptera: Psychodidae: Phlebotominae) in coffee agroecosystems

    PubMed Central

    Pérez, Jeanneth; Virgen, Armando; Rojas, Julio Cesar; Rebollar-Téllez, Eduardo Alfonso; Alfredo, Castillo; Infante, Francisco; Mikery, Oscar; Marina, Carlos Felix; Ibáñez-Bernal, Sergio

    2013-01-01

    The composition and seasonal occurrence of sandflies were investigated in coffee agroecosystems in the Soconusco region of Chiapas, Mexico. Insect sampling was performed on three plantations located at different altitudes: Finca Guadalupe Zajú [1,000 m above sea level (a.s.l.)], Finca Argovia (613 m a.s.l.) and Teotihuacán del Valle (429 m a.s.l.). Sandflies were sampled monthly from August 2007-July 2008 using three sampling methods: Shannon traps, CDC miniature light traps and Disney traps. Sampling was conducted for 3 h during three consecutive nights, beginning at sunset. A total of 4,387 sandflies were collected during the course of the study: 2,718 individuals in Finca Guadalupe Zajú, 605 in Finca Argovia and 1,064 in Teotihuacán del Valle. The Shannon traps captured 94.3% of the total sandflies, while the CDC light traps and Disney traps captured 4.9% and 0.8%, respectively. More females than males were collected at all sites. While the number of sandflies captured was positively correlated with temperature and relative humidity, a negative correlation was observed between sandfly numbers and rainfall. Five species of sandflies were captured: Lutzomyia cruciata , Lutzomyia texana , Lutzomyia ovallesi , Lutzomyia cratifer / undulata and Brumptomyia sp. Lu. cruciata , constituting 98.8% of the total, was the most abundant species. None of the captured sandflies was infected with Leishmania spp. PMID:24271002

  8. Detection of Rickettsia and Anaplasma from hard ticks in Thailand.

    PubMed

    Malaisri, Premnika; Hirunkanokpun, Supanee; Baimai, Visut; Trinachartvanit, Wachareeporn; Ahantarig, Arunee

    2015-12-01

    We collected a total of 169 adult hard ticks and 120 nymphs from under the leaves of plants located along tourist nature trails in ten localities. The results present data examining the vector competence of ticks of different genera and the presence of Rickettsia and Anaplasma species. The ticks belonged to three genera, Amblyomma, Dermacentor, and Haemaphysalis, comprising 11 species. Rickettsia bacteria were detected at three collection sites, while Anaplasma bacteria were detected at only one site. Phylogenetic analysis revealed new rickettsia genotypes from Thailand that were closely related to Rickettsia tamurae, Rickettsia monacensis, and Rickettsia montana. This study was also the first to show that Anaplasma bacteria are found in Haemaphysalis shimoga ticks and are closely related evolutionarily to Anaplasma bovis. These results provide additional information for the geographical distribution of tick species and tick-borne bacteria in Thailand and can therefore be applied for ecotourism management.

  9. Evaluating Functional Diversity: Missing Trait Data and the Importance of Species Abundance Structure and Data Transformation

    PubMed Central

    Bryndová, Michala; Kasari, Liis; Norberg, Anna; Weiss, Matthias; Bishop, Tom R.; Luke, Sarah H.; Sam, Katerina; Le Bagousse-Pinguet, Yoann; Lepš, Jan; Götzenberger, Lars; de Bello, Francesco

    2016-01-01

    Functional diversity (FD) is an important component of biodiversity that quantifies the difference in functional traits between organisms. However, FD studies are often limited by the availability of trait data and FD indices are sensitive to data gaps. The distribution of species abundance and trait data, and its transformation, may further affect the accuracy of indices when data is incomplete. Using an existing approach, we simulated the effects of missing trait data by gradually removing data from a plant, an ant and a bird community dataset (12, 59, and 8 plots containing 62, 297 and 238 species respectively). We ranked plots by FD values calculated from full datasets and then from our increasingly incomplete datasets and compared the ranking between the original and virtually reduced datasets to assess the accuracy of FD indices when used on datasets with increasingly missing data. Finally, we tested the accuracy of FD indices with and without data transformation, and the effect of missing trait data per plot or per the whole pool of species. FD indices became less accurate as the amount of missing data increased, with the loss of accuracy depending on the index. But, where transformation improved the normality of the trait data, FD values from incomplete datasets were more accurate than before transformation. The distribution of data and its transformation are therefore as important as data completeness and can even mitigate the effect of missing data. Since the effect of missing trait values pool-wise or plot-wise depends on the data distribution, the method should be decided case by case. Data distribution and data transformation should be given more careful consideration when designing, analysing and interpreting FD studies, especially where trait data are missing. To this end, we provide the R package “traitor” to facilitate assessments of missing trait data. PMID:26881747

  10. Evaluating Functional Diversity: Missing Trait Data and the Importance of Species Abundance Structure and Data Transformation.

    PubMed

    Májeková, Maria; Paal, Taavi; Plowman, Nichola S; Bryndová, Michala; Kasari, Liis; Norberg, Anna; Weiss, Matthias; Bishop, Tom R; Luke, Sarah H; Sam, Katerina; Le Bagousse-Pinguet, Yoann; Lepš, Jan; Götzenberger, Lars; de Bello, Francesco

    2016-01-01

    Functional diversity (FD) is an important component of biodiversity that quantifies the difference in functional traits between organisms. However, FD studies are often limited by the availability of trait data and FD indices are sensitive to data gaps. The distribution of species abundance and trait data, and its transformation, may further affect the accuracy of indices when data is incomplete. Using an existing approach, we simulated the effects of missing trait data by gradually removing data from a plant, an ant and a bird community dataset (12, 59, and 8 plots containing 62, 297 and 238 species respectively). We ranked plots by FD values calculated from full datasets and then from our increasingly incomplete datasets and compared the ranking between the original and virtually reduced datasets to assess the accuracy of FD indices when used on datasets with increasingly missing data. Finally, we tested the accuracy of FD indices with and without data transformation, and the effect of missing trait data per plot or per the whole pool of species. FD indices became less accurate as the amount of missing data increased, with the loss of accuracy depending on the index. But, where transformation improved the normality of the trait data, FD values from incomplete datasets were more accurate than before transformation. The distribution of data and its transformation are therefore as important as data completeness and can even mitigate the effect of missing data. Since the effect of missing trait values pool-wise or plot-wise depends on the data distribution, the method should be decided case by case. Data distribution and data transformation should be given more careful consideration when designing, analysing and interpreting FD studies, especially where trait data are missing. To this end, we provide the R package "traitor" to facilitate assessments of missing trait data.

  11. Prevalence of Borrelia burgdorferi Sensu Lato in Ticks Collected from Migratory Birds in Switzerland

    PubMed Central

    Poupon, Marie-Angèle; Lommano, Elena; Humair, Pierre-François; Douet, Véronique; Rais, Olivier; Schaad, Michael; Jenni, Lukas; Gern, Lise

    2006-01-01

    The prevalence of ticks infected by Borrelia burgdorferi sensu lato on birds during their migrations was studied in Switzerland. A total of 1,270 birds captured at two sites were examined for tick infestation. Ixodes ricinus was the dominant tick species. Prevalences of tick infestation were 6% and 18.2% for birds migrating northward and southward, respectively. Borrelia valaisiana was the species detected most frequently in ticks, followed by Borrelia garinii and Borrelia lusitaniae. Among birds infested by infected ticks, 23% (6/26) were infested by B. lusitaniae-infected larvae. Migratory birds appear to be reservoir hosts for B. lusitaniae. PMID:16391149

  12. Rickettsial and other tick-borne infections.

    PubMed

    Flicek, Barbara Fouts

    2007-03-01

    prophylaxsis is beneficial to the tick-bitten patient to prevent disease. It must be kept in mind that the risk of transmission of disease increases with the duration of attachment and generally requires greater than 24 to 48 hours. The degree of tick engorgement or the time since tick exposure and discovery of the tick may be used to establish the likely duration of attachment and the risk of disease transmission. Reducing and controlling tick populations is difficult. Habitat modifications, including vegetation management by cutting, burning, and herbicide treatment, and drainage of wet areas are one strategy for tick control, but their effects are often short-lived, and they can cause severe ecologic damage. Chemicals used to control ticks may cause environmental contamination, and therefore, toxicity for humans and animals. Biologic control methods for ticks include the promotion of natural predators. Natural predators of ticks are beetles, spiders, and ants, and parasites such as insects, mites and nematodes. Tick control is best based on the concept of integrated pest management, in which different control methods are adapted to one area or against one tick species with due consideration to their environmental effects. Tick-borne diseases are increasing in prevalence. Perhaps it is because people are undertaking more outdoor activities, which result in contact with ticks and their pathogens. Clinicians should be aware of the clinical sign of tick-transmitted diseases, because morbidity and mortality as a result of these diseases increases substantially if there are delays in diagnosis and treatment. Tick-borne illness occur in distinctive geographic areas. The reporting of these illnesses and diseases to the health department enables the gathering of information and statistics. The public should be informed about the risks of disease in tick-infested areas and the means of preventing infections. The most common diseases are caused by Rickettsia, Borrelia, and Ehrichia

  13. Models of experimentally derived competitive effects predict biogeographical differences in the abundance of invasive and native plant species.

    PubMed

    Xiao, Sa; Ni, Guangyan; Callaway, Ragan M

    2013-01-01

    Mono-dominance by invasive species provides opportunities to explore determinants of plant distributions and abundance; however, linking mechanistic results from small scale experiments to patterns in nature is difficult. We used experimentally derived competitive effects of an invader in North America, Acroptilon repens, on species with which it co-occurs in its native range of Uzbekistan and on species with which it occurs in its non-native ranges in North America, in individual-based models. We found that competitive effects yielded relative abundances of Acroptilon and other species in models that were qualitatively similar to those observed in the field in the two ranges. In its non-native range, Acroptilon can occur in nearly pure monocultures at local scales, whereas such nearly pure stands of Acroptilon appear to be much less common in its native range. Experimentally derived competitive effects of Acroptilon on other species predicted Acroptilon to be 4-9 times more proportionally abundant than natives in the North American models, but proportionally equal to or less than the abundance of natives in the Eurasian models. Our results suggest a novel way to integrate complex combinations of interactions simultaneously, and that biogeographical differences in the competitive effects of an invader correspond well with biogeographical differences in abundance and impact.

  14. Coxiella Detection in Ticks from Wildlife and Livestock in Malaysia

    PubMed Central

    Khoo, Jing-Jing; Lim, Fang-Shiang; Chen, Fezshin; Phoon, Wai-Hong; Khor, Chee-Sieng; Pike, Brian L.; Chang, Li-Yen

    2016-01-01

    Abstract Recent studies have shown that ticks harbor Coxiella-like bacteria, which are potentially tick-specific endosymbionts. We recently described the detection of Coxiella-like bacteria and possibly Coxiella burnetii in ticks found from rural areas in Malaysia. In the present study, we collected ticks, including Haemaphysalis bispinosa, Haemaphysalis hystricis, Dermacentor compactus, Dermacentor steini, and Amblyomma sp. from wildlife and domesticated goats from four different locations in Malaysia. Coxiella 16s rRNA genomic sequences were detected by PCR in 89% of ticks tested. Similarity analysis and phylogenetic analyses of the 16s rRNA and rpoB partial sequences were performed for 10 representative samples selected based on the tick species, sex, and location. The findings here suggested the presence of C. burnetii in two samples, each from D. steini and H. hystricis. The sequences of both samples clustered with published C. burnetii sequences. The remaining eight tick samples were shown to harbor 16s rRNA sequences of Coxiella-like bacteria, which clustered phylogenetically according to the respective tick host species. The findings presented here added to the growing evidence of the association between Coxiella-like bacteria and ticks across species and geographical boundaries. The importance of C. burnetii found in ticks in Malaysia warrants further investigation. PMID:27763821

  15. Thirty years of tick population genetics: a comprehensive review.

    PubMed

    Araya-Anchetta, Ana; Busch, Joseph D; Scoles, Glen A; Wagner, David M

    2015-01-01

    Population genetic studies provide insights into the basic biology of arthropod disease vectors by estimating dispersal patterns and their potential to spread pathogens. In wingless vectors, such as ticks, gene flow will be defined in large part by the mobility of their hosts. However, tick behaviors and life cycle strategies can limit their dispersal even on highly mobile hosts and lead to an increase in genetic structure. In this review we synthesize the published literature from three decades of tick population genetic studies. Based on studies from 22 tick species (including representatives from Amblyomma, Bothriocroton, Dermacentor, Ixodes, Ornithodoros, and Rhipicephalus), observed levels of population genetic structure in ticks varied from no structure to very high levels. In about half of the species (including representatives from Amblyomma, Bothriocroton, Dermacentor, and Ornithodoros), tick genetic structure appeared to be determined primarily by the movement capacity of hosts, with low gene flow observed in ticks that use smaller bodied less mobile hosts and high gene flow in ticks using highly mobile hosts. In a number of other species (primarily from Ixodes, Ornithodoros, and Rhipicephalus), behavioral limitations to gene flow appeared to result in greater genetic structure than expected based upon host movement capability alone. We also discuss the strengths and limitations of genetic markers and their applicability to ticks and suggest possible analyses when planning population genetic studies for ticks.

  16. Host Immunization with Recombinant Proteins to Screen Antigens for Tick Control.

    PubMed

    Galay, Remil Linggatong; Miyata, Takeshi; Umemiya-Shirafuji, Rika; Mochizuki, Masami; Fujisaki, Kozo; Tanaka, Tetsuya

    2016-01-01

    Ticks (Parasitiformes: Ixodida) are known for their obligate blood feeding habit and their role in transmitting pathogens to various vertebrate hosts. Tick control using chemical acaricides is extensively used particularly in livestock management, but several disadvantages arise from resistance development of many tick species, and concerns on animal product and environmental contamination. Vaccination offers better protection and more cost-effective alternative to application of chemical acaricides, addressing their disadvantages. However, an ideal anti-tick vaccine targeting multiple tick species and all the tick stages is still wanting. Here, we describe the procedures involved in the evaluation of a vaccine candidate antigen against ticks at the laboratory level, from the preparation of recombinant proteins, administration to the rabbit host and monitoring of antibody titer, to tick infestation challenge and determination of the effects of immunization to ticks.

  17. Deer ticks (image)

    MedlinePlus

    Diseases are often carried by ticks, including Rocky Mountain Spotted Fever, Colorado Tick Fever, Lyme disease, and tularemia. Less common or less frequent diseases include typhus, Q-fever, relapsing fever, viral encephalitis, hemorrhagic fever, ...

  18. The mitochondrial genome of the lone star tick (Amblyomma americanum).

    PubMed

    Williams-Newkirk, Amanda J; Burroughs, Mark; Changayil, Shankar S; Dasch, Gregory A

    2015-09-01

    Amblyomma americanum is an abundant tick in the southeastern, midwestern, and northeastern United States. It is a vector of multiple diseases, but limited genomic resources are available for it. We sequenced the complete mitochondrial genome of a single female A. americanum collected in Georgia using the Illumina platform. The consensus sequence was 14,709 bp long, and the mean coverage across the assembly was >12,000×. All expected tick genomic features were present, including two "Tick-Box" motifs, and in the expected order for the Metastriata. Heteroplasmy rates were low compared to the most closely related tick for which data are available, Amblyomma cajennense. The phylogeny derived from the concatenated protein coding and rRNA genes from the 33 available tick mitochondrial genomes was consistent with those previously proposed for the Acari. This is the first complete mitochondrial sequence for A. americanum, which provides a useful reference for future studies of A. americanum population genetics and tick phylogeny.

  19. Methods for control of tick vectors of Lyme Borreliosis

    USGS Publications Warehouse

    Jaenson, T.G.T.; Fish, D.; Ginsberg, H.S.; Gray, J.S.; Mather, T.N.; Piesman, J.

    1991-01-01

    During the IVth International Conference on Lyme Borreliosis in Stockholm, 1990, a workshop on control of Lyme disease vectors briefly reviewed: basic ecological principles for tick control; biocontrol of ticks; chemical control, including the use of repellents and use of permethrin-treated rodent nest material; tick control by habitat modification; and reduction of tick host availability. It was concluded that, although much research work remains, Lyme borreliosis is to a large extent a preventable infection. Avoidance of heavily tick-infested areas, personal protection using proper clothing, and prompt removal of attached ticks remain the most effective protective measures. Many other prophylactic measures are available and could be efficiently integrated into schemes to reduce the abundance of vectors. However, since the ecology of the infection varies greatly between different localities it may be necessary to apply different combinations of control methods in different endemic regions.

  20. Tick burden on European roe deer (Capreolus capreolus)

    PubMed Central

    Kiffner, Christian; Hagedorn, Peter; Niedrig, Matthias; Rühe, Ferdinand

    2010-01-01

    In our study we assessed the tick burden on roe deer (Capreolus capreolus L.) in relation to age, physical condition, sex, deer density and season. The main objective was to find predictive parameters for tick burden. In September 2007, May, July, and September 2008, and in May and July 2009 we collected ticks on 142 culled roe deer from nine forest departments in Southern Hesse, Germany. To correlate tick burden and deer density we estimated deer density using line transect sampling that accounts for different detectability in March 2008 and 2009, respectively. We collected more than 8,600 ticks from roe deer heads and necks, 92.6% of which were Ixodes spp., 7.4% Dermacentor spp. Among Ixodes, 3.3% were larvae, 50.5% nymphs, 34.8% females and 11.4% males, with significant seasonal deviation. Total tick infestation was high, with considerable individual variation (from 0 to 270 ticks/deer). Adult tick burden was positively correlated with roe deer body indices (body mass, age, hind foot length). Significantly more nymphs were found on deer from forest departments with high roe deer density indices, indicating a positive correlation with deer abundance. Overall, tick burden was highly variable. Seasonality and large scale spatial characteristics appeared to be the most important factors affecting tick burden on roe deer. PMID:20099011

  1. Tick burden on European roe deer (Capreolus capreolus).

    PubMed

    Vor, Torsten; Kiffner, Christian; Hagedorn, Peter; Niedrig, Matthias; Rühe, Ferdinand

    2010-08-01

    In our study we assessed the tick burden on roe deer (Capreolus capreolus L.) in relation to age, physical condition, sex, deer density and season. The main objective was to find predictive parameters for tick burden. In September 2007, May, July, and September 2008, and in May and July 2009 we collected ticks on 142 culled roe deer from nine forest departments in Southern Hesse, Germany. To correlate tick burden and deer density we estimated deer density using line transect sampling that accounts for different detectability in March 2008 and 2009, respectively. We collected more than 8,600 ticks from roe deer heads and necks, 92.6% of which were Ixodes spp., 7.4% Dermacentor spp. Among Ixodes, 3.3% were larvae, 50.5% nymphs, 34.8% females and 11.4% males, with significant seasonal deviation. Total tick infestation was high, with considerable individual variation (from 0 to 270 ticks/deer). Adult tick burden was positively correlated with roe deer body indices (body mass, age, hind foot length). Significantly more nymphs were found on deer from forest departments with high roe deer density indices, indicating a positive correlation with deer abundance. Overall, tick burden was highly variable. Seasonality and large scale spatial characteristics appeared to be the most important factors affecting tick burden on roe deer.

  2. Ticks (Acari: Ixodida) infesting humans in the provinces of Kelkit Valley, a Crimean-Congo Hemorrhagic Fever endemic region in Turkey.

    PubMed

    Bursali, Ahmet; Keskin, Adem; Tekin, Saban

    2013-04-01

    Ticks are mandatory blood feeding ectoparasites leading transmission of various tick-borne pathogens to human and animals. Since 2002, thousands of human tick bites and numerous Crimean-Congo Hemorrhagic Fever cases have been reported in several provinces in the Kelkit Valley region in Turkey. Despite increased cases of tick bites and tick-borne diseases, no taxonomic information is available about the tick species infesting humans in the region. In the present study, a tick survey on humans was performed to determine the species composition of ticks infesting humans in several provinces of Kelkit Valley. In the survey, 1,460 ticks (721 males, 516 females and 223 nymphs) were collected from tick-infested humans. A total of 19 tick species have been found on humans in the region, including 7 Hyalomma, 2 Argas, 2 Haemaphysalis, 2 Ixodes, Dermacentor and 3 Rhipicephalus species. Infestation of Dermacentor reticulatus on humans was documented for the first time in Turkey.

  3. Ticks imported to Europe with exotic reptiles.

    PubMed

    Mihalca, Andrei Daniel

    2015-09-30

    It is known that traded exotic animals carry with them an immense number of associated symbionts, including parasites. Reptiles are no exception. Most of the imported reptiles originate from tropical countries and their possibility to carry potentially dangerous pathogens is high. According to CITES, Europe is currently the main reptile importer in the world. Despite this, there is no review or analysis available for the risk related to the importation of tick-borne diseases with traded reptile to the EU. The main aim of the manuscript is to provide a review on the available literature on ticks introduced to and exchanged between European countries via the live reptile trade. So far, the published reports of ticks imported on reptiles are limited to few European countries: Italy, Poland, Spain, Netherlands, Belgium, Slovenia and UK. The following species have been reported: Hyalomma aegyptium, Amblyomma dissimile, Amblyomma exornatum, Amblyomma flavomaculatum, Amblyomma fuscolineatum, Amblyomma latum, Amblyomma quadricavum, Amblyomma marmoreum, Amblyomma nuttalli, Amblyomma sparsum, Amblyomma sphenodonti, Amblyomma transversale and Amblyomma varanense. The majority of species are of African origin, followed by American and Asian species. All groups of reptiles (chelonians, snakes, lizards, crocodiles, tuataras) were involved. However, it seems that certain groups (i.e. tortoises of genus Testudo, monitor lizards of genus Varanus, snakes of genus Python) are more important as host for imported ticks, but this may be related to higher levels of international trade. Even fewer are the reports of tick-borne pathogens associated with imported reptile ticks. Despite the diversity of tick species reported on imported reptiles, the situations of truly invasive species are atypical and are limited in natural environments to maximum two cases where H. aegyptium was involved. Otherwise, the risk associated with reptile trade for introduction of invasive tick to Europe is low

  4. Abiotic and biotic factors associated with tick population dynamics on a mammalian host: Ixodes hexagonus infesting otters, Lutra lutra.

    PubMed

    Sherrard-Smith, Ellie; Chadwick, Elizabeth; Cable, Joanne

    2012-01-01

    The Eurasian otter, Lutra lutra, hosts several parasites with zoonotic potential. As this semiaquatic mammal has large ranges across terrestrial, freshwater and marine habitats, it has the capacity for wide dispersion of pathogens. Despite this, parasites of otters have received relatively little attention. Here, we examine their ectoparasite load and assess whether this is influenced by abiotic or biotic variables. Climatic phenomena such as the North Atlantic Oscillation (NAO) affect weather conditions in northern Europe. Consequently parasite distributions, particularly species with life stages exposed to the external environment, can be affected. We assessed the extent to which inter-annual variations in large-scale weather patterns (specifically the NAO and Central England (CE) temperatures) and host characteristics influenced tick prevalence and intensity. Ectoparasites consisted of a single species, the nidiculous tick Ixodes hexagonus (prevalence = 24.3%; mean intensity = 7.2; range = 1-122; on n = 820 otter hosts). The prevalence, but not intensity of infestation, was associated with high CE temperatures, while both prevalence and intensity were associated with positive phases of the NAO. Such associations indicate that I. hexagonus are most abundant when weather conditions are warmer and wetter. Ticks were more prevalent on juvenile than sub-adult or adult otters, which probably reflects the length of time the hosts spend in the holt where these ticks quest. High tick number was associated with poor host condition, so either poor condition hosts are more susceptible to ticks, or tick infestations negatively impact on host condition. Otters are clearly an important and common host for I. hexagonus, which has implications for vector-borne diseases. This work is the first to consider the impacts of long-term weather patterns on I. hexagonus and uses wild-animal cadavers to illustrate the importance of abiotic and biotic pressures impacting parasitic

  5. Dynamic relationships between body size, species richness, abundance, and energy use in a shallow marine epibenthic faunal community.

    PubMed

    Labra, Fabio A; Hernández-Miranda, Eduardo; Quiñones, Renato A

    2015-01-01

    We study the temporal variation in the empirical relationships among body size (S), species richness (R), and abundance (A) in a shallow marine epibenthic faunal community in Coliumo Bay, Chile. We also extend previous analyses by calculating individual energy use (E) and test whether its bivariate and trivariate relationships with S and R are in agreement with expectations derived from the energetic equivalence rule. Carnivorous and scavenger species representing over 95% of sample abundance and biomass were studied. For each individual, body size (g) was measured and E was estimated following published allometric relationships. Data for each sample were tabulated into exponential body size bins, comparing species-averaged values with individual-based estimates which allow species to potentially occupy multiple size classes. For individual-based data, both the number of individuals and species across body size classes are fit by a Weibull function rather than by a power law scaling. Species richness is also a power law of the number of individuals. Energy use shows a piecewise scaling relationship with body size, with energetic equivalence holding true only for size classes above the modal abundance class. Species-based data showed either weak linear or no significant patterns, likely due to the decrease in the number of data points across body size classes. Hence, for individual-based size spectra, the SRA relationship seems to be general despite seasonal forcing and strong disturbances in Coliumo Bay. The unimodal abundance distribution results in a piecewise energy scaling relationship, with small individuals showing a positive scaling and large individuals showing energetic equivalence. Hence, strict energetic equivalence should not be expected for unimodal abundance distributions. On the other hand, while species-based data do not show unimodal SRA relationships, energy use across body size classes did not show significant trends, supporting energetic

  6. Dynamic relationships between body size, species richness, abundance, and energy use in a shallow marine epibenthic faunal community

    PubMed Central

    Labra, Fabio A; Hernández-Miranda, Eduardo; Quiñones, Renato A

    2015-01-01

    We study the temporal variation in the empirical relationships among body size (S), species richness (R), and abundance (A) in a shallow marine epibenthic faunal community in Coliumo Bay, Chile. We also extend previous analyses by calculating individual energy use (E) and test whether its bivariate and trivariate relationships with S and R are in agreement with expectations derived from the energetic equivalence rule. Carnivorous and scavenger species representing over 95% of sample abundance and biomass were studied. For each individual, body size (g) was measured and E was estimated following published allometric relationships. Data for each sample were tabulated into exponential body size bins, comparing species-averaged values with individual-based estimates which allow species to potentially occupy multiple size classes. For individual-based data, both the number of individuals and species across body size classes are fit by a Weibull function rather than by a power law scaling. Species richness is also a power law of the number of individuals. Energy use shows a piecewise scaling relationship with body size, with energetic equivalence holding true only for size classes above the modal abundance class. Species-based data showed either weak linear or no significant patterns, likely due to the decrease in the number of data points across body size classes. Hence, for individual-based size spectra, the SRA relationship seems to be general despite seasonal forcing and strong disturbances in Coliumo Bay. The unimodal abundance distribution results in a piecewise energy scaling relationship, with small individuals showing a positive scaling and large individuals showing energetic equivalence. Hence, strict energetic equivalence should not be expected for unimodal abundance distributions. On the other hand, while species-based data do not show unimodal SRA relationships, energy use across body size classes did not show significant trends, supporting energetic

  7. Edge-interior differences in the species richness and abundance of drosophilids in a semideciduous forest fragment.

    PubMed

    Penariol, Leiza V; Madi-Ravazzi, Lilian

    2013-12-01

    Habitat fragmentation is the main cause of biodiversity loss, as remnant fragments are exposed to negative influences that include edge effects, prevention of migration, declines in effective population sizes, loss of genetic variability and invasion of exotic species. The Drosophilidae (Diptera), especially species of the genus Drosophila, which are highly sensitive to environmental variation, have been used as bioindicators. A twelve-month field study was conducted to evaluate the abundance and richness of drosophilids in an edge-interior transect in a fragment of semideciduous forest in São Paulo State, Brazil. One objective of the study was to evaluate the applied methodology with respect to its potential use in future studies addressing the monitoring and conservation of threatened areas. The species abundance along the transect showed a clear gradient, with species associated with disturbed environments, such as Drosophila simulans, Scaptodrosophila latifasciaeformis and Zaprionus indianus, being collected at the fragment edge and the species D. willistoni and D. mediostriata being found in the fragment's interior. Replacement of these species occurred at approximately 60 meters from the edge, which may be a reflection of edge effects on species abundance and richness because the species found within the habitat fragment are more sensitive to variations in temperature and humidity than those sampled near the edge. The results support the use of this methodology in studies on environmental impacts.

  8. Changing geographic ranges of ticks and tick-borne pathogens: drivers, mechanisms and consequences for pathogen diversity

    PubMed Central

    Ogden, Nick H.; Mechai, Samir; Margos, Gabriele

    2013-01-01

    The geographic ranges of ticks and tick-borne pathogens are changing due to global and local environmental (including climatic) changes. In this review we explore current knowledge of the drivers for changes in the ranges of ticks and tick-borne pathogen species and strains via effects on their basic reproduction number (R0), and the mechanisms of dispersal that allow ticks and tick-borne pathogens to invade suitable environments. Using the expanding geographic distribution of the vectors and agent of Lyme disease as an example we then investigate what could be expected of the diversity of tick-borne pathogens during the process of range expansion, and compare this with what is currently being observed. Lastly we explore how historic population and range expansions and contractions could be reflected in the phylogeography of ticks and tick-borne pathogens seen in recent years, and conclude that combined study of currently changing tick and tick-borne pathogen ranges and diversity, with phylogeographic analysis, may help us better predict future patterns of invasion and diversity. PMID:24010124

  9. Changing geographic ranges of ticks and tick-borne pathogens: drivers, mechanisms and consequences for pathogen diversity.

    PubMed

    Ogden, Nick H; Mechai, Samir; Margos, Gabriele

    2013-01-01

    The geographic ranges of ticks and tick-borne pathogens are changing due to global and local environmental (including climatic) changes. In this review we explore current knowledge of the drivers for changes in the ranges of ticks and tick-borne pathogen species and strains via effects on their basic reproduction number (R 0), and the mechanisms of dispersal that allow ticks and tick-borne pathogens to invade suitable environments. Using the expanding geographic distribution of the vectors and agent of Lyme disease as an example we then investigate what could be expected of the diversity of tick-borne pathogens during the process of range expansion, and compare this with what is currently being observed. Lastly we explore how historic population and range expansions and contractions could be reflected in the phylogeography of ticks and tick-borne pathogens seen in recent years, and conclude that combined study of currently changing tick and tick-borne pathogen ranges and diversity, with phylogeographic analysis, may help us better predict future patterns of invasion and diversity.

  10. Worldwide distribution and diversity of seabird ticks: implications for the ecology and epidemiology of tick-borne pathogens.

    PubMed

    Dietrich, Muriel; Gómez-Díaz, Elena; McCoy, Karen D

    2011-05-01

    The ubiquity of ticks and their importance in the transmission of pathogens involved in human and livestock diseases are reflected by the growing number of studies focusing on tick ecology and the epidemiology of tick-borne pathogens. Likewise, the involvement of wild birds in dispersing pathogens and their role as reservoir hosts are now well established. However, studies on tick-bird systems have mainly focused on land birds, and the role of seabirds in the ecology and epidemiology of tick-borne pathogens is rarely considered. Seabirds typically have large population sizes, wide geographic distributions, and high mobility, which make them significant potential players in the maintenance and dispersal of disease agents at large spatial scales. They are parasitized by at least 29 tick species found across all biogeographical regions of the world. We know that these seabird-tick systems can harbor a large diversity of pathogens, although detailed studies of this diversity remain scarce. In this article, we review current knowledge on the diversity and global distribution of ticks and tick-borne pathogens associated with seabirds. We discuss the relationship between seabirds, ticks, and their pathogens and examine the interesting characteristics of these relationships from ecological and epidemiological points of view. We also highlight some future research directions required to better understand the evolution of these systems and to assess the potential role of seabirds in the epidemiology of tick-borne pathogens.

  11. Determinants of distribution and abundance of two shrub species, Guiera senegalensis and Piliostigma reticulatum, in Peanut Basin, Senegal

    NASA Astrophysics Data System (ADS)

    Lufafa, A.; Diédhiou, I.; Ndiaye, N.; Kizito, F.; Dick, R.; Noller, J. S.

    2005-05-01

    The ability to predict and manage the course of landscape-level ecological change and its longer-term consequences on ecosystem functions (e.g. carbon stabilization and soil degradation mitigation) depends on the ability to understand how a particular ecosystem functions and the mechanisms that control the distribution, configuration and abundance of key species. Guiera senegalensis and Piliostigma reticulatum are two native shrub species that are widely found in Sub-Saharan Africa but unrecognized in their potential role in regulating hydrological and carbon cycles in both natural and agro-ecosystems. Our objective was to conduct a study on the determinants of landscape-level distribution and abundance of these shrub species as a basis for ecological modeling and management of this fragile semiarid environment. Formal Recursive Inference Modeling was used to adduce determinants of species presence while logistic regression and geostatistical approaches were used to estimate shrub abundance within their communities. The results showed that distribution of the shrubs is controlled by four factors: geological substrate, mean annual temperature, mean annual rainfall and landform (profile convexity). Relative abundance within the shrub communities is under the influence of mean annual rainfall, maximum annual temperature and elevation (for G. senegalensis) and mean annual rainfall, mean annual temperature, elevation and landform (profile convexity) (for P. reticulatum). Predictive models for shrub distribution and abundance were generally poor, probably highlighting the weakness of statistical models in analysis and quantification of the spatial structure of ecosystems.

  12. Species Diversity, Abundance, and Host Preferences of Mosquitoes (Diptera: Culicidae) in Two Different Ecotypes of Madagascar With Recent RVFV Transmission.

    PubMed

    Jean Jose Nepomichene, Thiery Nirina; Elissa, Nohal; Cardinale, Eric; Boyer, Sebastien

    2015-09-01

    Mosquito diversity and abundance were examined in six Madagascan villages in either arid (Toliary II district) or humid (Mampikony district) ecotypes, each with a history of Rift Valley fever virus transmission. Centers for Disease Control and Prevention light traps without CO2 (LT) placed near ruminant parks and animal-baited net trap (NT) baited with either zebu or sheep/goat were used to sample mosquitoes, on two occasions between March 2011 and October 2011. Culex tritaeniorhynchus (Giles) was the most abundant species, followed by Culex antennatus (Becker) and Anopheles squamosus/cydippis (Theobald/de Meillon). These three species comprised more than half of all mosquitoes collected. The NT captured more mosquitoes in diversity and in abundance than the LT, and also caught more individuals of each species, except for An. squamosus/cydippis. Highest diversity and abundance were observed in the humid and warm district of Mampikony. No host preference was highlighted, except for Cx. tritaeniorhynchus presenting a blood preference for zebu baits. The description of species diversity, abundance, and host preference described herein can inform the development of control measures to reduce the risk of mosquito-borne diseases in Madagascar.

  13. [Species-abundance distribution patterns along succession series of Phyllostachys glauca forest in a limestone mountain].

    PubMed

    Shi, Jian-min; Fan, Cheng-fang; Liu, Yang; Yang, Qing-pei; Fang, Kai; Fan, Fang-li; Yang, Guang-yao

    2015-12-01

    To detect the ecological process of the succession series of Phyllostachys glauca forest in a limestone mountain, five niche models, i.e., broken stick model (BSM), niche preemption model (NPM), dominance preemption model (DPM), random assortment model (RAM) and overlap- ping niche model (ONM) were employed to describe the species-abundance distribution patterns (SDPs) of 15 samples. χ² test and Akaike information criterion (AIC) were used to test the fitting effects of the five models. The results showed that the optimal SDP models for P. glauca forest, bamboo-broadleaved mixed forest and broadleaved forest were DPM (χ² = 35.86, AIC = -69.77), NPM (χ² = 1.60, AIC = -94.68) and NPM (χ² = 0.35, AIC = -364.61), respectively. BSM also well fitted the SDP of bamboo-broadleaved mixed forest and broad-leaved forest, while it was unsuitable to describe the SDP of P. glauca forest. The fittings of RAM and ONM in the three forest types were all rejected by the χ² test and AIC. With the development of community succession from P. glauca forest to broadleaved forest, the species richness and evenness increased, and the optimal SDP model changed from DPM to NPM. It was inferred that the change of ecological process from habitat filtration to interspecific competition was the main driving force of the forest succession. The results also indicated that the application of multiple SDP models and test methods would be beneficial to select the best model and deeply understand the ecological process of community succession.

  14. Free-living ixodid ticks in an urban Atlantic Forest fragment, state of Rio de Janeiro, Brazil.

    PubMed

    Pinheiro, Michele da Costa; Lourenço, Elizabete Captivo; Patrício, Priscilla Maria Peixoto; Sá-Hungaro, Iwine Joyce Barbosa de; Famadas, Kátia Maria

    2014-01-01

    As a consequence of the importance of ticks in forests in protected areas, was conducted survey of species of free-living ticks in the Natural Park Municipal Curió, state of Rio de Janeiro, Brazil. Monthly samples were taken by dragging method, dry ice traps and visual search in two transects. Adults and nymphs of Amblyomma cajennense (n= 147), Amblyomma brasiliense (n= 4) and Amblyomma parvum (n= 1) were collected. This is the first occurrence of A. parvum in the state. No correlation was found between the abundance of stages of A. cajennense and rainfall, temperature and relative humidity. The highest abundances of adults were in the months of January and May, and