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1

Faecal egg counts provide a reliable measure of Trichostrongylus tenuis intensities in free-living red grouse Lagopus lagopus scoticus  

Microsoft Academic Search

The reliability of different egg counting methods for estimating the intensity of Trichostrongylus tenuis infections in red grouse, Lagopus lagopus scoticus, was investigated in the autumn, when grouse may harbour high parasite intensities. Possible limitations to the use of these methods were also examined. Faecal egg counts were found to accurately estimate T. tenuis worm intensities, at least up to

L. J. Seivwright; S. M. Redpath; F. Mougeot; L. Watt; P. J. Hudson

2004-01-01

2

MATRILINEAL GENETIC STRUCTURE AND FEMALE-MEDIATED GENE FLOW IN RED GROUSE (LAGOPUS LAGOPUS SCOTICUS): AN ANALYSIS USING MITOCHONDRIAL DNA  

Microsoft Academic Search

DNA sequence variation at the hypervariable 59 end of the mitochondrial control region was examined in 247 individuals to detect genetic divergence among 14 populations of red grouse (Lagopus lagopus scoticus )i n northeastern Scotland. Ten haplotypes were resolved, several of which were shared among populations. Analysis of molecular variance, Nei's gST, and a cladistic estimate of the amount of

Stuart B. Piertney; Andrew D. C. MacColl; Philip J. Bacon; Paul A. Racey; Xavier Lambin; John F. Dallas

2000-01-01

3

Insights into population ecology from long-term studies of red grouse Lagopus lagopus scoticus.  

PubMed

Long-term studies have been the backbone of population ecology. The red grouse Lagopus lagopus scoticus is one species that has contributed widely to this field since the 1950s. This paper reviews the trajectory and profound impact that these studies have had. Red grouse research has combined long-term studies of marked individuals with demographic studies over wide geographical areas and replicated individual- and population-level manipulations. A main focus has been on understanding the causes of population cycles in red grouse, and in particular the relative importance of intrinsic (behaviour) and extrinsic (climate, food limitation and parasite) mechanisms. Separate studies conducted in different regions initially proposed either the nematode parasite Trichostrongylus tenuis or changes in male aggressiveness in autumn as drivers of population cycles. More recent experiments suggest that parasites are not a necessary cause for cycles and have highlighted that behavioural and parasite-mediated mechanisms are interrelated. Long-term experiments show that parasites and aggressiveness interact. Two outstanding questions remain to be tested experimentally. First, what intrinsic mechanism causes temporal variation in patterns of male aggressiveness? The current favoured mechanism is related to patterns of kin structuring although there are alternative hypotheses. Second, how do the dual, interacting mechanisms, affect population dynamics? Red grouse studies have had an important impact on the field of population ecology, in particular through highlighting: (1) the impact of parasites on populations; (2) the role of intrinsic mechanisms in cyclic dynamics and (3) the need to consider multiple, interacting mechanisms. PMID:23800249

Martínez-Padilla, Jesus; Redpath, Steve M; Zeineddine, Mohammed; Mougeot, François

2014-01-01

4

Ornamental comb colour predicts T-cell-mediated immunity in male red grouse Lagopus lagopus scoticus  

NASA Astrophysics Data System (ADS)

Sexual ornaments might reliably indicate the ability to cope with parasites and diseases, and a better ability to mount a primary inflammatory response to a novel challenge. Carotenoid-based ornaments are amongst the commonest sexual signals of birds and often influence mate choice. Because carotenoids are immuno-stimulants, signallers may trade-off allocating these to ornamental colouration or using them for immune responses, so carotenoid-based ornaments might be particularly useful as honest indicators of immuno-compentence. Tetraonid birds, such as the red grouse Lagopus lagopus scoticus, exhibit supra-orbital yellow red combs, a conspicuous ornament which functions in intra- and inter-sexual selection. The colour of combs is due to epidermal pigmentation by carotenoids, while their size is testosterone-dependent. In this study, I investigated whether comb characteristics, and in particular, comb colour, indicated immuno-competence in free-living male red grouse. I assessed T-cell-mediated immunity using a standardised challenge with phytohaemagglutinin. Red grouse combs reflect in the red and in the ultraviolet spectrum of light, which is not visible to humans but that grouse most likely see, so I measured comb colour across the whole bird visible spectrum (300 700 nm) using a reflectance spectrometer. I found that males with bigger and redder combs, but with less ultraviolet reflectance, had greater T-cell-mediated immune response. Comb colour predicted T-cell-mediated immune response better than comb size, indicating that the carotenoid-based colouration of this ornament might reliably signal this aspect of male quality.

Mougeot, Francois

2008-02-01

5

Visceral gout in a rough legged hawk (Buteo lagopus).  

PubMed

Visceral gout is reported for the first time in a rough legged hawk (Buteo lagopus). Urate crystals were present on the pericardium, thoracic and abdominal air sacs, and the ventral surface of the liver. The liver and spleen also had urate crystals throughout the parenchyma. There was no indication of articular or renal involvement. The immediate cause of death in this hawk was not identified, but appeared to result from multiple factors, including the visceral gout. PMID:3625918

Murnane, R D; Garner, M M

1987-07-01

6

Fine-scale population epigenetic structure in relation to gastrointestinal parasite load in red grouse (Lagopus lagopus scotica).  

PubMed

Epigenetic modification of cytosine methylation states can be elicited by environmental stresses and may be a key process affecting phenotypic plasticity and adaptation. Parasites are potent stressors with profound physiological and ecological effects on their host, but there is little understanding in how parasites may influence host methylation states. Here, we estimate epigenetic diversity and differentiation among 21 populations of red grouse (Lagopus lagopus scotica) in north-east Scotland and test for association of gastrointestinal parasite load (caecal nematode Trichostrongylus tenuis) with hepatic genome-wide and locus-specific methylation states. Following methylation-sensitive AFLP (MSAP), 129 bands, representing 73 methylation-susceptible and 56 nonmethylated epiloci, were scored across 234 individuals. The populations differed significantly in genome-wide methylation levels and were also significantly epigenetically (F(SC) = 0.0227; P < 0.001) and genetically (F(SC) = 0.0058; P < 0.001) differentiated. Parasite load was not associated with either genome-wide methylation levels or epigenetic differentiation. Instead, we found eight disproportionately differentiated epilocus-specific methylation states (F(ST) outliers) using bayescan software and significant positive and negative association of 35 methylation states with parasite load from bespoke generalized estimating equations (GEE), simple logistic regression (sam) and Bayesian environmental analysis (bayenv2). Following Sanger sequencing, genome mapping and geneontology (go) annotation, some of these epiloci were linked to genes involved in regulation of cell cycle, signalling, metabolism, immune system and notably rRNA methylation, histone acetylation and small RNAs. These findings demonstrate an epigenetic signature of parasite load in populations of a wild bird and suggest intriguing physiological effects of parasite-associated cytosine methylation. PMID:24943398

Wenzel, Marius A; Piertney, Stuart B

2014-09-01

7

Fine-scale population epigenetic structure in relation to gastrointestinal parasite load in red grouse (Lagopus lagopus scotica)  

PubMed Central

Epigenetic modification of cytosine methylation states can be elicited by environmental stresses and may be a key process affecting phenotypic plasticity and adaptation. Parasites are potent stressors with profound physiological and ecological effects on their host, but there is little understanding in how parasites may influence host methylation states. Here, we estimate epigenetic diversity and differentiation among 21 populations of red grouse (Lagopus lagopus scotica) in north-east Scotland and test for association of gastrointestinal parasite load (caecal nematode Trichostrongylus tenuis) with hepatic genome-wide and locus-specific methylation states. Following methylation-sensitive AFLP (MSAP), 129 bands, representing 73 methylation-susceptible and 56 nonmethylated epiloci, were scored across 234 individuals. The populations differed significantly in genome-wide methylation levels and were also significantly epigenetically (FSC = 0.0227; P < 0.001) and genetically (FSC = 0.0058; P < 0.001) differentiated. Parasite load was not associated with either genome-wide methylation levels or epigenetic differentiation. Instead, we found eight disproportionately differentiated epilocus-specific methylation states (FST outliers) using bayescan software and significant positive and negative association of 35 methylation states with parasite load from bespoke generalized estimating equations (GEE), simple logistic regression (sam) and Bayesian environmental analysis (bayenv2). Following Sanger sequencing, genome mapping and geneontology (go) annotation, some of these epiloci were linked to genes involved in regulation of cell cycle, signalling, metabolism, immune system and notably rRNA methylation, histone acetylation and small RNAs. These findings demonstrate an epigenetic signature of parasite load in populations of a wild bird and suggest intriguing physiological effects of parasite-associated cytosine methylation. PMID:24943398

WENZEL, MARIUS A; PIERTNEY, STUART B

2014-01-01

8

Detecting hybridization between willow grouse ( Lagopus lagopus ) and rock ptarmigan ( L. muta ) in Central Sweden through Bayesian admixture analyses and mtDNA screening  

Microsoft Academic Search

Willow grouse (L. lagopus) and rock ptarmigan (L. muta) are sibling species with similar phenotypic and life histories that coexist sympatrically in wide areas of their distribution\\u000a range. These grouse are amongst the most popular game birds in Scandinavia but contrary to other quarry species, no restocking\\u000a with captive-bred animals has ever been performed. The discovery of two individuals with

María Quintela; Carl-Gustaf Thulin; Jacob Höglund

2010-01-01

9

Breeding Season Irruptions of Rough-legged Hawks (Buteo lagopus) on Insular Newfoundland  

Microsoft Academic Search

Rough-legged hawks (Buteo lagopus Pontoppidan), a species typically associated with more northerly regions, occurred in unusually high numbers on insular Newfoundland in the summers of 1988 and 1993, and some pairs nested in noncoastal areas on the island in 1993. We suggest that the island is an alternative breeding ground for the species during years of low prey abundance on

DARROCH M. WHITAKER; WILLIAM A. MONTEVECCHI; JOHN W. GOSSE

1996-01-01

10

DIFFERENTIAL WINTER DISTRIBUTION OF ROUGH-LEGGED HAWKS (BUTEO LAGOPUS) BY SEX IN WESTERN  

Microsoft Academic Search

AmSTP, nCT. We conducted roadside surveys of Rough-legged Hawks (Buteo lagopus) in Montana, Cali- fornia, and Nevada for four consecutive winters from 1995-96 through 1998-99. The proportion of adult males to adult females and of adults to juveniles in the samples did not change significantly throughout the winter at any location. Adult females outnumbered adult males on all but one

DAVID P. ARSENAULT

2000-01-01

11

Arctic Fox (Alopex lagopus) Dens in the Disko Bay Area, West Greenland  

Microsoft Academic Search

Seventeen arctic fox (Alopex lagopus) dens in the Disko Bay area, West Greenland are described regarding location, type, size and vegetation cover. The dens were found in ridges, screes and level ground, mainly in areas of dwarf-scrub heath. The mean number of entrances was 17.8 ± 18.4 SD (range 1-63), with more than half of the dens having fewer than

SUSSIE M. NIELSEN; VIVI PEDERSEN; BENTE BANG KLITGAARD

1994-01-01

12

Description of the life stages of quill mite Mironovia lagopus sp. nov. (Acari: Syringophilidae) parasitizing the rock ptarmigan Lagopus muta (Phasianidae) from Iceland.  

PubMed

A new species of syringophilid mites, Mironovia lagopus sp. nov. (Acari: Syringophilidae) is described from feather quills of the rock ptarigman Lagopus muta (Montin) (Phasianidae) from Iceland. Females of this new species differ from the closely related Mironovia rouloul Skoracki and Sikora by setae d2, which are subequal or 1.1-1.2 times shorter than setae e2 (vs. d2 1.4-1.5 times longer than e2 in Mironovia rouloul) and by setae ag1, which are 1.3-1.5 times shorter than ag2 (vs. ag1 1.7-1.8 times shorter than ag2). The postembryonic stages of this new species are figured and described in details. In ontogeny of Mironovia spp., the observed pattern of setal appearance is not different from the pattern in other galliform-associated genera such as Syringophilus and Colinophilus, with exception for tarsal setae p'I, II which are absent in protonymphs. The key to all four species of the genus Mironovia is also provided. PMID:20978793

Bochkov, Andre V; Skirnisson, Karl

2011-03-01

13

Free love in the far north: plural breeding and polyandry of arctic foxes ( Alopex lagopus ) on Bylot Island, Nunavut  

Microsoft Academic Search

Molecular studies show that canid breeding systems are more complex than field data have sometimes sug- gested. For example, microsatellite DNA fingerprints of offspring and adults within their social group indicate that many canid species thought to form monogamous pairs engage in polygyny, polyandry, and plural breeding. In many areas, arc- tic foxes (Alopex lagopus (L., 1758)) are considered monogamous,

L. E. Carmichael; G. Szor; D. Berteaux; M. A. Giroux; C. Cameron; C. Strobeck

2007-01-01

14

Validation of the Feeding Test as an Index of Fear in Farmed Blue ( Alopex lagopus) and Silver Foxes ( Vulpes vulpes)  

Microsoft Academic Search

The reliability and validity of the eating behaviour in the presence of man (Feeding test) as an index of fear were assessed in farmed blue (Alopex lagopus) and silver foxes (Vulpes vulpes). Repeatability of the Feeding test was good in both species. No further habituation occurred after the fourth successive test in either species. In addition, the behaviour of both

Teppo Rekilä; Mikko Harri; Leena Ahola

1997-01-01

15

First characterization in China of Encephalitozoon cuniculi in the blue fox (Alopex lagopus).  

PubMed

Encephalitozoon cuniculi is a microsporidian parasite that infects a wide range of vertebrates, including primates. It has recently emerged as an opportunistic parasite of patients infected with the human immunodeficiency virus. The blue fox (Alopex lagopus; also known as the arctic fox) is one of the most susceptible species for encephalitozoonosis. Here, we report an outbreak of encephalitozoonosis at a fox farm in China. The isolated parasites displayed the typical morphology of E. cuniculi as assessed by Masson's trichrome staining. Analysis of the internal transcribed spacer sequence indicated that the isolated parasite is a genotype III strain of E. cuniculi. Furthermore, phylogenetic analysis of the PTP1 gene verifies classification of this new strain (termed LN-1) with other genotype III E. cuniculi strains, though the PTP3 and SWP1 sequences diverge from the reference strain. This is the first report of encephalitozoonosis in farmed blue foxes in China. PMID:24995428

Meng, Xiangchun; Zheng, Jun; He, Xijun; Jia, Honglin; Zhang, Yanlong

2014-01-01

16

Effect of body condition on tissue distribution of perfluoroalkyl substances (PFASs) in Arctic fox (Vulpes lagopus).  

PubMed

Arctic animals undergo large seasonal fluctuations in body weight. The effect of body condition on the distribution and composition of 16 perfluoroalkyl substances (PFASs) was investigated in liver, blood, kidney, adipose tissue, and muscle of Arctic foxes (Vulpes lagopus) from Svalbard (n = 18, age 1-3 years). PFAS concentrations were generally highest in liver, followed by blood and kidney, while lowest concentrations were found in adipose tissue and muscle. Concentrations of summed perfluorocarboxylic acids and perfluoroalkyl sulfonates were five and seven times higher, respectively, in adipose tissue of lean compared to fat foxes. In addition, perfluorodecanoate (PFDA) and perfluoroheptanesulfonate (PFHpS) concentrations in liver, kidney, and blood, and, perfluorononanoate (PFNA) in liver and blood, were twice as high in the lean compared to the fat foxes. The ratio between perfluorooctane sulfonamide (FOSA) and its metabolite perfluorooctanesulfonate (PFOS) was lowest in liver, muscle, and kidney, while significantly higher proportions of FOSA were found in adipose tissue and blood. The results of the present study suggest that toxic potential of exposure to PFAS among other pollutants in Arctic mammals may increase during seasonal emaciation. The results also suggest that body condition should be taken into account when assessing temporal trends of PFASs. PMID:25215880

Aas, Camilla Bakken; Fuglei, Eva; Herzke, Dorte; Yoccoz, Nigel G; Routti, Heli

2014-10-01

17

Reduced Metabolic Cost of Locomotion in Svalbard Rock Ptarmigan (Lagopus muta hyperborea) during Winter  

PubMed Central

The Svalbard rock ptarmigan, Lagopus muta hyperborea experiences extreme photoperiodic and climatic conditions on the Arctic archipelago of Svalbard. This species, however, is highly adapted to live in this harsh environment. One of the most striking adaptations found in these birds is the deposition, prior to onset of winter, of fat stores which may comprise up to 32% of body mass and are located primarily around the sternum and abdominal region. This fat, while crucial to the birds' survival, also presents a challenge in that the bird must maintain normal physiological function with this additional mass. In particular these stores are likely to constrain the respiratory system, as the sternum and pelvic region must be moved during ventilation and carrying this extra load may also impact upon the energetic cost of locomotion. Here we demonstrate that winter birds have a reduced cost of locomotion when compared to summer birds. A remarkable finding given that during winter these birds have almost twice the body mass of those in summer. These results suggest that Svalbard ptarmigan are able to carry the additional winter fat without incurring any energetic cost. As energy conservation is paramount to these birds, minimising the costs of moving around when resources are limited would appear to be a key adaptation crucial for their survival in the barren Arctic environment. PMID:21125015

Lees, John; Nudds, Robert; Stokkan, Karl-Arne; Folkow, Lars; Codd, Jonathan

2010-01-01

18

Foods of arctic foxes (Alopex lagopus) during winter and spring in western Alaska  

USGS Publications Warehouse

During 1986-1991, carcasses of 619 arctic fares (Alopex lagopus) collected from local trappers and at biological field camps on the Yukon-Kuskokwim Delta in western Alaska from November through May were analyzed to determine gastrointestinal contents, age, sex, and body condition. Prey in declining order of importance were small mammals (95% tundra voles, Microtus oeconomus), birds, marine mammals, and fishes. Foxes with small mammal remains in their stomachs were captured farther from the Bering Sea coast ((X) over bar = 5.2 km) than those without small-mammal remains (2.8 km); foxes consuming remains of marine mammals were closer to the coast (1.9 km) than others (4.9 km). Although eggshells had a poor likelihood of occurrence in stomachs, they were found in all months and years. In 1986 and 1987, foxes consumed fewer small mammals than in other years. Mean ages of foxes captured in 1986 (3.7 years) and 1987 (3.2) were greater than in all ether years (1.5). Capture of adults was more common as winter progressed. Indexes of subcutaneous fat decreased annually in April-May and were highest in 1991, when occurrence of carrion of marine mammals was highest.

Anthony, M.; Barten, N.K.; Seiser, P.E.

2000-01-01

19

Concentrations of selected essential and non-essential elements in arctic fox ( Alopex lagopus) and wolverines ( Gulo gulo) from the Canadian Arctic  

Microsoft Academic Search

Arctic fox (Alopex lagopus) and wolverine (Gulo gulo) tissues were collected in the Canadian Arctic from 1998 to 2001 and analyzed for various essential and non-essential elements. Several elements (Ag, Al, As, B, Ba, Be, Co, Cr, Mo, Ni, Sb, Sn, Sr, Tl, U and V) were near or below the detection limits in >95% arctic fox and wolverine samples.

P. F. Hoekstra; B. M. Braune; B. Elkin; F. A. J. Armstrong; D. C. G. Muir

2003-01-01

20

Quantifying fenbendazole and its metabolites in self-medicating wild red grouse Lagopus lagopus scoticus using an HPLC–MS–MS approach  

Microsoft Academic Search

On red grouse estates in the UK the nematode parasite Trichostrongylus tenuis is often controlled by application of grit medicated with the anthelmintic fenbendazole (FBZ). To date, assessment of the efficacy has been inhibited by the inability to quantify uptake of FBZ by the birds. We have developed a simple and sensitive HPLC–MS–MS method for detecting and quantifying FBZ and

Aileen Adam; Lucy M. I. Webster; William Mullen; Lukas F. Keller; Paul C. D. Johnson

2011-01-01

21

Is alloparenting helpful for Mednyi Island arctic foxes, Alopex lagopus semenovi?  

NASA Astrophysics Data System (ADS)

The Arctic Fox Alopex lagopus semenovi population on Mednyi Island is completely isolated and subsists largely by scavenging on seabird colonies, which have remained abundant and spatio-temporally predictable for many years. We compared population data at the beginning of 1976/1978 and some time after 1994-2005, finding an 85% decline in fox numbers due to disease, to assess the effect of population size on social structure. A total of 81 groups of known size and composition was observed during this 29-year period. Overall, helpers (usually non-lactating yearling females) occurred in 25.7% of groups, and in 32.4% of groups there were two or three lactating females. Female engagement in alloparental behaviour decreased, but not statistically significantly, after the decline in population density. Total food availability was apparently constant throughout the study period, and therefore, the amount available per individual was much higher later in the study. Both communally nursing females and helpers brought food and helped to guard the litter. However, the benefits of communal rearing were unclear. While cubs were left without guards significantly more rarely in the groups with an additional adult, the number of cubs weaned per lactating female was greater in groups with one (3.93 ± 1.60), as opposed to two or three (3.06 ± 0.92), lactating females. Survival of cubs to 1 year of age in the groups with two lactating females and/or with helpers was lower than that in the families with one lactating female without helpers (22.2% vs 32.2%). Fewer second-generation litters were born to foxes produced by composite families than to those produced by pairs. Reproductive adults producing by pairs had, on average, 1.23 (±1.72) second-generation litters. In groups that initially included additional adults, the average number of second-generation litters per reproductive female was 0.21 (±0.49) and 0.46 (±0.81) litters per male. Thus, according to three measures, increased group size had no apparent positive impact on reproductive success. The increased parental investment and enhanced guarding of the cubs in the larger families could be beneficial under conditions of high population density and a saturated biotope to which the island fox population was presumably adapted before the population crash in the late 1970s.

Kruchenkova, Elena P.; Goltsman, Michael; Sergeev, Sergei; MacDonald, David W.

2009-04-01

22

Accumulation and potential health effects of organohalogenated compounds in the arctic fox (Vulpes lagopus)-a review.  

PubMed

This review addresses biological effects of anthropogenic organohalogenated compounds in the arctic fox (Vulpes lagopus). When considering the current levels, spatial and tissue distributions of selected organic pollutants in arctic fox subpopulations, especially the Svalbard based populations accumulate high levels. The dominating contaminant groups are the polychlorinated biphenyls (PCBs) and chlordanes (CHLs), which reach high levels in adipose tissues, adrenals and liver. Recent controlled exposure studies on domesticated arctic fox and Greenland sledge dogs, show adverse health effects associated with OC concentrations lower than those measured in free-ranging populations. This indicates that especially populations at Svalbard may be at risk of experiencing OC related effects. The arctic fox as such may be an overlooked species in the Arctic Monitoring and Assessment Programs and it would add further information about pollution in the Arctic to include this species in the monitoring program. PMID:25300015

Pedersen, Kathrine Eggers; Styrishave, Bjarne; Sonne, Christian; Dietz, Rune; Jenssen, Bjørn Munro

2015-01-01

23

The digestion of bulbils (Polygonum viviparum L.) and berries (Vaccinium myrtillus L. and Empetrum sp.) by captive ptarmigan (Lagopus mutus).  

PubMed

1. The digestion of three foods favoured by ptarmigan (Lagopus mutus) in the wild was studied using captive birds. 2. Bulbils of Polygonum viviparum L. were a good source of metabolizable energy, protein and phosphorus, but were deficient in sodium. Berries of Vaccinium myrtillus L. were the most digestible of the three foods, contained enough protein and P for maintenance, but were probably deficient in Na. A diet of Empetrum sp. berries caused the birds to be in negative nitrogen and P balance, but provided adequate Na. Both species of berries were rich sources of soluble carbohydrate. 3. In the wild, ptarmigan eat a mixed diet, which presumably provides adequate Na, protein and P. 4. The relative proportions of the various end-products of N metabolism varied according to the protein content of the food. With the diet of Vaccinium berries (11 g N/kg dry matter) roughly equal amounts of ammonium salts and urates were excreted. With Polygonum bulbils (29 g N/kg dry matter) the quantities of ammonium salts and urates excreted were similar to those with Vaccinium berries, but some urea was also excreted and about half the N in the birds' droppings was in an unidentified form. 5. When eating Empetrum berries, ptarmigan digested lignin and tannins and excreted ornithurates. The benzoic acid moiety of the ornithuric acid molecule may have been derived partly from the digested lignin and tannins. PMID:1167787

Moss, R; Parkinson, J A

1975-03-01

24

Mineral density and biomechanical properties of bone tissue from male Arctic foxes (Vulpes lagopus) exposed to organochlorine contaminants and emaciation.  

PubMed

We investigated the impact from dietary OC (organochlorine) exposure and restricted feeding (emaciation) on bone mineral density (BMD; g hydroxy-apatite cm(-2)) in femoral, vertebrate, skull and baculum osteoid tissue from farmed Arctic blue foxes (Vulpes lagopus). For femur, also biomechanical properties during bending (displacement [mm], load [N], energy absorption [J] and stiffness [N/mm]) were measured. Sixteen foxes (EXP) were fed a wet food containing 7.7% OC-polluted minke whale (Balaenoptera acutorostrata) blubber in two periods of body fat deposition (Aug-Dec) and two periods of body fat mobilisation (Jan-July) in which the food contained less energy and only 2% blubber. SigmaOC food concentration in the food containing 7.7% whale blubber was 309 ng/g wet mass. This corresponded to a SigmaOC exposure of ca. 17 microg/kg body mass/d and a responding SigmaOC residue in subcutaneous adipose tissue of ca. 1700 ng/g live mass in the 8 EXP fat foxes euthanized after 16 months. A control group (CON) composed of 15 foxes were fed equal daily caloric amounts of clean pork (Sus scrofa) fat. After 16 months, 8 EXP and 7 CON foxes were euthanized (mean body mass=9.25 kg) while the remaining 8 EXP and 8 CON foxes were given restricted food rations for 6 months resulting in a body weight reduction (mean body mass=5.46 kg). The results showed that only BMD(skull) vs. BMD(vertebrae) were significantly correlated (R=0.68; p=0.03; n=10) probably due to a similar composition of trabecular and cortical osteoid tissue. No difference in any of the BMD measurements or femoral biomechanical properties was found between EXP and CON foxes although BMD baculum was 1.6-folds lower in the EXP group. However, lean summer foxes had significantly lower femoral biomechanical properties measured as displacement (mm), energy absorption (J) and time (s) biomechanical properties than fat winter foxes (all p<0.004). This indicates lower stiffness and softer bones from fasting which is in agreement with previous studies. Further, it should be kept in mind when studying bone tissues in Arctic mammals also in order to avoid confounding effects from body condition. PMID:18761108

Sonne, Christian; Wolkers, Hans; Rigét, Frank F; Jensen, Jens-Erik Beck; Teilmann, Jenni; Jenssen, Bjørn Munro; Fuglei, Eva; Ahlstrøm, Øystein; Dietz, Rune; Muir, Derek C G; Jørgensen, Even H

2009-01-01

25

Comparative aspects of sperm membrane fatty acid composition in silver (Vulpes vulpes) and blue (Alopex lagopus) foxes, and their relationship to cell cryopreservation.  

PubMed

Cryogenic protocols have been developed for the storage of farmed silver fox (Vulpes vulpes) spermatozoa. However, these same protocols and modifications of these protocols have failed to satisfactorily preserve spermatozoa collected from farmed blue foxes (Alopex lagopus). Because cryogenic success has been linked to membrane composition, the plasma membrane lipid composition of farmed blue fox and silver fox spermatozoa was studied. Silver fox spermatozoal membranes have significantly higher levels of docosapentaenoic acid (DPA; 22:5, n-6) compared to blue fox spermatozoa, and blue fox spermatozoal membranes have significantly higher levels of stearic acid (18:0). Silver fox spermatozoal membranes not only have a higher ratio of unsaturated/saturated membrane fatty acids, but also higher levels of membrane desmosterol and cholesterol. PMID:16040024

Miller, R R; Cornett, C L; Waterhouse, K E; Farstad, W

2005-08-01

26

The role of non-viraemic transmission on the persistence and dynamics of a tick borne virus--Louping ill in red grouse ( Lagopus lagopus scoticus) and mountain hares ( Lepus timidus).  

PubMed

There exist many tick borne infections that are of either economic or public health interest. Mathematical models have previously been used to describe the dynamics of these infections. However it has recently come to light that there is an alternative mechanism for the transmission of these diseases that has not been considered in a modelling framework. This is transmission through ticks co-feeding on non-viraemic hosts. This paper extends a simple mathematical model to include this alternative transmission mechanism. The model is used to describe the dynamics of Louping ill virus in red grouse (the viraemic host) and hares (the non-viraemic host). However, these results are applicable to many other systems. The model is analysed using joint threshold density curves. It is found that the presence of a non-viraemic host allows the virus to persist more readily than it would in the presence of a host that simply amplified the tick population. More importantly, if the level of non-viraemic transmission is high enough the virus can persist in the absence of the viraemic host. This result has important implications for the control of tick borne diseases. PMID:14745507

Norman, Rachel; Ross, David; Laurenson, M Karen; Hudson, Peter J

2004-02-01

27

Levels and temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard in relation to dietary habits and food availability.  

PubMed

Temporal trends of persistent organic pollutants (POPs) in arctic foxes (Vulpes lagopus) from Svalbard, Norway, were investigated in relation to feeding habits and seasonal food availability. Arctic foxes from Svalbard forage in both marine and terrestrial ecosystems and the availability of their food items are impacted by climatic variability. Concentrations of polychlorinated biphenyls (PCBs), organochlorinated pesticides (OCPs) and brominated flame retardants (polybrominated diphenyl ethers [PBDEs] and hexabromocyclododecane [HBCDD]) were analyzed in the liver of 141 arctic foxes collected between 1997 and 2013. Stable carbon isotope values (?(13)C) were used as a proxy for feeding on marine versus terrestrial prey. The annual number of recovered reindeer carcasses and sea ice cover were used as proxies for climate influenced food availability (reindeers, seals). Linear models revealed that concentrations of PCBs, chlordanes, p,p'-DDE, mirex and PBDEs decreased 4-11% per year, while no trends were observed for hexachlorobenzene (HCB) or ?-hexachlorocyclohexane (?-HCH). Positive relationships between POP concentrations and ?(13)C indicate that concentrations of all compounds increase with increasing marine dietary input. Increasing reindeer mortality was related to lower HCB concentrations in the foxes based on the linear models. This suggests that concentrations of HCB in arctic foxes may be influenced by high mortality levels of Svalbard reindeer. Further, ?-HCH concentrations showed a positive association with sea ice cover. These results in addition to the strong effect of ?(13)C on all POP concentrations suggest that climate-related changes in arctic fox diet are likely to influence contaminant concentrations in arctic foxes from Svalbard. PMID:25536177

Andersen, Martin S; Fuglei, Eva; König, Max; Lipasti, Inka; Pedersen, Åshild Ø; Polder, Anuschka; Yoccoz, Nigel G; Routti, Heli

2015-04-01

28

Genetic and ecological data provide incongruent interpretations of population structure and dispersal in naturally subdivided populations of white-tailed ptarmigan (Lagopus leucura).  

PubMed

The dispersal of individuals among populations affects the demographic and adaptive trajectories of animal populations and is fundamental to understanding population dynamics. White-tailed ptarmigan (Lagopus leucura) are a high elevation grouse species that live year-round in patchily distributed alpine areas in western North America. We investigated the patterns of dispersal and identified barriers to gene flow for a threatened subspecies (L. l. saxatilis) endemic to Vancouver Island, Canada. Connectivity among seven sites was examined using nine microsatellite loci (n = 133 individuals, H(O) = 0.62, mean number of alleles = 10) and direct movement observations using radio-telemetry (n = 118 individuals). Average movement distances of individuals measured by radio-telemetry were 0.63-3.23 km and considerably less than the shortest distance between sampling sites (18 km). Furthermore, despite extensive radio-telemetry data, movement was never observed between any of the seven sampling sites. In contrast, genetic results (STRUCTURE, TESS) showed connectivity among most of the seven sampling sites and suggested that genetic variation is best explained by two clusters of individuals which separated the South sampling site from all other areas of Vancouver Island. Analysis of molecular data also showed a generally consistent pattern of isolation by distance (Mantel test r = 0.11, P < 0.01) with large areas of unsuitable low elevation habitat possibly acting as barriers to gene flow. Despite the naturally subdivided distribution of populations, white-tailed ptarmigan do not fit well into any common definition of a metapopulation. We conclude the incongruities between the genetic and radio-telemetry data are best explained by episodic dispersal patterns. In this study, we demonstrated the importance of combining genetic and ecological data in understanding patterns of dispersal and population structure. PMID:18363666

Fedy, B C; Martin, K; Ritland, C; Young, J

2008-04-01

29

Analysis of aggregation, a worked example: numbers of ticks on red grouse chicks  

E-print Network

563 Analysis of aggregation, a worked example: numbers of ticks on red grouse chicks D. A. ELSTON ricinus on red grouse Lagopus lagopus scoticus chicks to temporal (year), spatial (altitude and location. ricinus on chicks of red grouse Lagopus lagopus scoticus as an example. The Poisson distribution

Lambin, Xavier

30

Ecological Modelling 147 (2002) 291307 The kin facilitation hypothesis for red grouse population  

E-print Network

Ecological Modelling 147 (2002) 291­307 The kin facilitation hypothesis for red grouse population grouse population cycles to the formation of spatial assemblages comprising related territory holders clusters; Kinship; Ordinary differential equations; Population cycles; Red grouse (Lagopus lagopus scoticus

Lambin, Xavier

31

COMMUNAL ROOSTS OF WINTERING ROUGH-LEGGED HAWKS (BUTEO LAGOPUS)  

Microsoft Academic Search

This study was conducted in an approximately 120-square-mile area near the center of DeKalb County. The terrain varies from flat to gently rolling, with over 90 per cent of the soil in agriculture and more than 80 per cent of the county in cropland. While prairie grasses once covered about 92 per cent of DeKalb County, they are virtually gone

GARY D. SCHNELL

32

ORIGINAL ARTICLE Carotenoid-based colouration and ultraviolet reflectance  

E-print Network

of grouse F. Mougeot & J. Martínez-Padilla & L. Pérez-Rodríguez & G. R. Bortolotti Received: 7 April 2006 roles in mate choice. Grouse (Tetraonidae) exhibit bright carotenoid-dependent sexual ornaments is not visible to humans but is likely to be visible to grouse. In male red grouse Lagopus lagopus scoticus, we

Bortolotti, Gary R.

33

The association of grouse moor in Scotland with the illegal use of poisons to control predators  

Microsoft Academic Search

In the UK uplands, there is a conflict between the maintenance of high densities of red grouse (Lagopus lagopus scoticus) for sporting shoots and the conservation of birds of prey on grouse moors where shoots take place. Several authors have indicated that as a result of this conflict, illegal use of poisoned baits to control predators is more likely to

D. Philip Whitfield; David R. A McLeod; Jeff Watson; Alan H Fielding; Paul F Haworth

2003-01-01

34

Social class, socially-induced loss, recruitment and breeding of red grouse  

Microsoft Academic Search

Individually marked red grouse (Lagopus lagopus scoticus) could be distinguished as territorial or non-territorial from November till the next spring. Territorial birds survived well and many reared young, but numerous nonterritorial birds died or disappeared, and none paired up or reared young. Differences in spring sex ratio between years had already been set in the previous autumn's territorial stock. Many

Adam Watson

1985-01-01

35

Habitat loss and raptor predation: disentangling long- and short-term causes of red grouse declines  

Microsoft Academic Search

The number of red grouse ( Lagopus lagopus scoticus ) shot in the UK has declined by 50% during the 20th century. This decline has coincided with reductions in the area of suitable habitat and recoveries in the populations of some avian predators. Here we use long-term records of shooting bags and a large-scale manipulation of raptor density to disentangle

Simon J. Thirgood; Steve M. Redpath; Daniel T. Haydon; Peter Rothery; Ian Newton; Peter J. Hudson

2000-01-01

36

Population Cycles and Parasitism Hudson et al. (1) used anthelmintics to re-  

E-print Network

in cyclic red grouse (Lagopus lagopus scoticus) managed for shooting, and claimed to have stopped popu and 1993 declines in grouse numbers in response to treatment, but their measure of grouse numbers counts (3). Hudson et al. compared numbers of grouse shot with numbers actually counted in one con- trol

Lambin, Xavier

37

Journal of Animal Ecology 2003  

E-print Network

Ltd. Territorial behaviour and population dynamics in red grouse Lagopus lagopus scoticus. II, Tillydrone Avenue, Aberdeen AB24 2TZ, Scotland, UK Summary 1. Recent experiments on cyclic red grouse grouse cycles can be recast in the current terminology, and how the new models offer a more general way

Lambin, Xavier

38

Population structure of spotted seatrout, Cynoscion nebulosus, in Texas bays and estuaries as revealed by analysis of microsatellite DNA  

E-print Network

, Silver S ~~ ~rag, MD. 14 Piertney SB, MacColl ADC, Bacon P J, Dallas JF (1998) Local genetic structure in red grouse (Lagopus lagopus scoticus): evidence from microsatellite DNA markers. Molecular Ecology, 7, 1645-1654. Ramsey PR, Wakeman JM (1987...

Stewart, Leah Beth

2013-02-22

39

Risk of parasite-induced predation: an experimental field study on Townsend's voles  

E-print Network

townsendii) Harald Steen, Mary Taitt, and Charles J. Krebs Abstract: Studies of causes of mortality townsendii, experimentally rid of parasites are less likely to be killed by predators than are control voles ro- dents, snowshoe hares (Lepus americanus), and red grouse (Lagopus lagopus scoticus) (rodents

Krebs, Charles J.

40

Linking nest histories, remotely sensed land use data and wildlife crime records to explore the impact of grouse moor management on peregrine falcon populations  

Microsoft Academic Search

Wildlife crime can be difficult to quantify, and its true impact on populations can be underestimated if rates are under-recorded. The illegal killing of birds of prey is an important form of wildlife crime, which in the UK, is often associated with land managed for the recreational shooting of red grouse Lagopus lagopus scoticus. In the UK, increases in peregrine

Arjun Amar; Ian R. Court; Martin Davison; Steve Downing; Trevor Grimshaw; Terry Pickford; David Raw

41

Using Decision Modeling with Stakeholders to Reduce Human-Wildlife Conflict: a Raptor-Grouse Case Study  

Microsoft Academic Search

Abstract: The successful resolution of human-wildlife,conflicts requires the participation,of local communi- ties and other stakeholder groups in formulating management decisions. In the uplands of the United Kingdom, a controversial,conservation,issue concerns,the relationship between,the conservation,of a legally protected raptor, the Hen Harrier (Circus cyaneus) and the management of a gamebird, the Red Grouse (Lagopus lagopus scoticus). We used multicriteria analysis to evaluate

S. M. REDPATH; B. E. ARROYO; F. M. LECKIE; P. BACON; N. BAYFIELD; R. J. GUTIERREZ; S. J. THIRGOOD

2004-01-01

42

An Experimental Evaluation of the Arctic Fox (Alopex lagopus) as a Seed Disperser  

Microsoft Academic Search

Arctic foxes are evaluated as seed dispersal vectors for Greenlandic plant species through a feeding experiment with subsequent scat analysis and germination test. Seeds of 22 common species with different morphology were tested. Passage time ranged between 4 and 48 h. No significant differences were detected in passage time for seeds with different morphology. Cerastium alpinum and Stellaria longipes had

Bente J. Graae; Sussie Pagh; Hans Henrik Bruun

2004-01-01

43

The genetics of body condition and leg weakness in the blue fox (Alopex lagopus)  

Microsoft Academic Search

In recent years, the size and fatness of blue foxes have increased because the length of the pelt is an important factor affecting its price. However, extreme fatness poses a risk to the animal's welfare and increased body weight (BW) has been suspected as a predisposing factor for leg weakness (LEG). The main purpose of this study was to estimate

R. Kempe; N. Koskinen; E. Mäntysaari; I. Strandén

2010-01-01

44

Population cycles in rock ptarmigan Lagopus muta: modelling and parameter estimation  

Microsoft Academic Search

Abstract We have modelled,population,change,of rock ptarmigan,using data from spring censuses and age ratios (spring and late summer),from a study area in north-east Iceland 1981 ? 2004. Modelling of mortality rates has shown,a significant time trend (increasing) for mortality of adult birds (Z,X;W has, however, changed in a cyclic way peaking 2 ? 4 years after the peak in ptarmigan,numbers. The

Kjartan G. Magnússon; Ólafur K. Nielsen

2004-01-01

45

Handling during pregnancy in the blue fox (Alopex lagopus): the influence on the fetal gonadal function.  

PubMed

In previous studies it has been shown that handling produced stress in pregnant blue fox vixens increasing plasma level and adrenal in vitro production of cortisol. Moreover, this treatment increased plasma cortisol levels in the fetuses. The present study was designed to examine effects of a 1-min daily handling stress applied to pregnant blue fox vixens on fetal gonadal steroidogenesis. Plasma concentrations of oestradiol and testosterone, gonadal content and gonadal in vitro production of these steroids, and response to exogenous hCG as well as gonadal weights, and anogenital distances were measured in control (C, n=69) and stressed (S, n=54) fetuses on 47-48 days of pregnancy. Maternal stress induced a suppression of gonadal steroidogenesis in the fetuses. The decreased testosterone content in the testes and oestradiol content in the ovaries were demonstrated in stressed fetuses compared with control (testosterone: 4.91+/-0.46 vs. 7.35+/-0.87 ng/both testes, P<0.05; oestradiol: 29.1+/-3.4 vs. 46.5+/-4.9 ng/both ovaries, P<0.05). The ovarian oestradiol in vitro production in female fetuses from stressed mothers was decreased in comparison with control (3.69+/-0.39 vs. 7.52+/-1.51 pg/ovary/h, P<0.05). The same difference was observed between stressed and control male fetuses in the testosterone testicular response to hCG (5.34+/-0.64 vs. 8.73+/-0.40 ng/testis/h, P<0.05). The ovarian weight from stressed fetuses was lower in comparison with control (12.9+/-0.7 vs. 16.8+/-0.6 mg, P<0.05). The anogenital distance in female fetuses from stressed vixens was also reduced (0.6+/-0.03 vs. 0.8+/-0.02 cm, P<0.01). These results indicate that prenatal stress resulted in a significant reduction of hormonal and morphometric measures of the reproductive system in blue fox fetuses with more drastic effects in female fetuses. PMID:12812765

Osadchuk, Ludmila V; Braastad, Bjarne O; Hovland, Anna-Lena; Bakken, Morten

2003-06-15

46

Female foraging and male vigilance in white-tailed ptarmigan ( Lagopus leucurus ): opportunism or behavioural coordination?  

Microsoft Academic Search

For several species of birds, high rates of male vigilance are correlated with high rates of female foraging. This relationship\\u000a is thought to ultimately result in higher reproductive success for females paired with highly vigilant males. However, previous\\u000a research has not examined the behavioural mechanism that produces the correlation between male vigilance and rates of female\\u000a foraging. Foraging females may

Thomas Artiss; Wesley M. Hochachka; Kathy Martin

1999-01-01

47

Analysis of aggregation, a worked example: numbers of ticks on red grouse chicks.  

PubMed

The statistical aggregation of parasites among hosts is often described empirically by the negative binomial (Poisson-gamma) distribution. Alternatively, the Poisson-lognormal model can be used. This has the advantage that it can be fitted as a generalized linear mixed model, thereby quantifying the sources of aggregation in terms of both fixed and random effects. We give a worked example, assigning aggregation in the distribution of sheep ticks Ixodes ricinus on red grouse Lagopus lagopus scoticus chicks to temporal (year), spatial (altitude and location), brood and individual effects. Apparent aggregation among random individuals in random broods fell 8-fold when spatial and temporal effects had been accounted for. PMID:11393830

Elston, D A; Moss, R; Boulinier, T; Arrowsmith, C; Lambin, X

2001-05-01

48

Ecology, 86(8), 2005, pp. 21762186 2005 by the Ecological Society of America  

E-print Network

Willow Ptarmigan (Lagopus lagopus) and White- tailed Ptarmigan (L. leucurus) breeding at subalpine-offs; grouse; Lagopus lagopus; Lagopus leucurus; lambda; life history strategies; survival; White. Corresponding Editor: C. W. Fox. 4 E-mail: bsanderc@ksu.edu seeking ecological correlates of life history

Sandercock, Brett K.

49

Influence of Dietary Fat Source on the Body Fat Composition of Mink (Mustela vison) and Blue Fox (Alopex lagopus)  

Microsoft Academic Search

The influence of dietary fat source on the fatty acid composition of mink and blue fox fat in different parts of the body was studied. In addition, seasonal changes in the fatty acid composition of the skin and subcutaneous fat were determined. The dietary fat sources used in the experiments were beef tallow, mink fat, capelin oil, soybean oil and

Kirsti Rouvinen; Tuomo Kiiskinen

1989-01-01

50

Hormones and metabolites of arctic foxes (Alopex lagopus) in response to season, starvation and re-feeding.  

PubMed

Svalbard's arctic foxes experience large seasonal variations in light, temperature and food supply throughout the year, which may result in periods of starvation. The aim of this work is to investigate if there are seasonal variations in post-absorptive plasma thyroid hormones (free thyroxin (fT(4)), free triiodothyronine (fT(3)) and reverse triiodothyronine (rT(3))) and metabolites (free fatty-acids (FFA) and beta-hydroxybutyrate (beta-OHB)) with season and their response to starvation and re-feeding. The concentrations of post-absorptive free triiodothyronine were significantly higher in November than May, while those of thyroxin, reverse triiodothyronine, free fatty-acids and beta-hydroxybutyrate remained unchanged. Possible explanations for the seasonal variations in free triiodothyronine are discussed. There were no significant changes from post-absorptive concentrations of thyroxin and reverse triiodothyronine in starved and re-fed foxes. However, free triiodothyronine concentrations decreased during starvation and increased again with re-feeding both in May and November. Starvation induced high levels of free fatty acids in both May and November, indicating increased lipolysis. There was a significant increase in beta-hydroxybutyrate in November only, indicating that arctic foxes are capable of protein conservation during starvation. PMID:10936768

Fuglei, E; Aanestad, M; Berg, J P

2000-06-01

51

Alterations of the pituitary-gonadal axis in the neonatal blue fox (Alopex lagopus) exposed to prenatal handling stress.  

PubMed

Handling is a stressor for blue foxes. The influence of preterm handling (1 min daily) of vixens was investigated in 68, 10-day-old cubs, 34 male and 34 female. Body, gonadal and pituitary weight, ano-genital distance, gonadal testosterone and oestradiol content and in vitro production, and pituitary LH content were measured in all cubs. The gonads were frozen or incubated in vitro with, or without, added hCG (2.5 IU per sample). The gonadal incubates and homogenates were analysed for testosterone and oestradiol by radioimmunoassay and the pituitary homogenates for LH by immunofluorometric assay. The results indicate that neonatal fox gonads actively produce steroids and that there are significant sex differences in basal steroid production and response of the gonads to hCG, and in pituitary LH content. Maternal stress resulted in a significant reduction of morphometric and hormonal measures of the reproductive system in neonatal blue foxes, with more drastic effects in female cubs. Gonadal weights were lower in cubs of both sexes from stressed vixens (65.7+/-4.3 v 50.6+/-1.8 mg for the ovaries and 23.2+/-1.0 v. 17.7+/-1.0 mg for the testes, control v. stressed animals, P<0.01). The ano-genital distance in female offspring of stressed vixens was reduced (1.1+/-0.04 v. 0.9+/-0.03 cm, P<0.01). Basal ovarian oestradiol and testosterone production were decreased in cubs from prenatally stressed animals in comparison with controls (43.5+/-3.5 v. 32.6+/-3.7 pg ovary(-1) h(-1) and 0.40+/-0.16 v. 0.12+/-0.03 ng ovary(-1) h , P<0.05). Prenatal stress did not affect either pituitary weights or LH content in either sex. There were no significant differences in ano-genital distance, testicular content of testosterone, or in vitro testosterone production between control and treated male cubs. In conclusion, these findings suggest that prenatal handling stress impaired the neonatal reproductive development of the female offspring, but had no marked effects on males. Sex-specific effects of prenatal handling stress on the reproductive development in foxes may be linked with the gender differences in responses of the hypothalamus-pituitary-adrenocortical axis to stress conditions in this species. PMID:11302420

Osadchuka, L V; Braastad, B O; Huhtaniemi, I; Bakken, M

2000-01-01

52

The ornament-condition relationship varies with parasite abundance at population level in a female bird  

NASA Astrophysics Data System (ADS)

Environmental heterogeneity is expected to create variation in the ornament-condition relationship. This topic has been studied in males with less attention being given to females. Here, we explore inter-population variation in the relationship between the size of a male-like trait, supra-orbital combs, and body mass in female red grouse Lagopus lagopus scoticus. We used the abundance of the nematode Trichostrongylus tenuis, a parasite with strong negative effects on this species, as a proxy of environmental conditions. We studied six populations over 5 years and showed that the comb size-body mass relationship varied with mean parasite abundance, with stronger ornament-condition relationships in populations with higher parasite infection levels. Our study supports the idea that environmental conditions, and in particular parasite infection levels, may affect the reliability of female ornaments as condition indicators.

Vergara, Pablo; Martínez-Padilla, Jesús; Redpath, Stephen M.; Mougeot, Francois

2011-10-01

53

Effects of seasonality and fasting on the body mass and plasma growth hormone concentrations of the raccoon dog (Nyctereutes procyonoides) and the blue fox (Alopex lagopus).  

PubMed

Growth hormone (GH) promotes growth and endochondral ossification, but it is also important in the response to fasting due to its effects of increasing gluconeogenesis and lipolysis. In this study eleven raccoon dogs and blue foxes were followed for six months and their body mass and GH levels were measured. In November half of the animals of both species were put to a three-week fast. There were no significant differences in the GH levels between the animals of different ages and the subadults and adults both had quite low GH levels in the summer. Fasting had no effect on the GH levels of the raccoon dogs, but the fasting blue foxes had lower GH concentrations than the controls in Nov 16th. The control blue foxes experienced a significant increase in the GH levels in early November and the fasting blue foxes in late November. The GH concentrations of all the raccoon dogs rose in early December. As fasting did not cause an elevation in the GH levels but the concentrations increased with decreasing temperature and shortening daylength, the autumnal GH secretion of these species could be regulated by endogenous seasonal rhythms entrained by exogenous Zeitgebers such as temperature or photoperiod. The autumnal increase of GH levels contributes to the response to fasting as an adaptation to survive the winter months with inadequate nutrition. The raccoon dog which spends the coldest part of the winter in winter sleep seems to be better adapted to a total fast than the actively wintering blue fox. PMID:11421462

Mustonen, A M; Nieminen, P; Hyvärinen, H; Asikainen, J

2001-01-01

54

A base substitution in the donor site of intron 12 of KIT gene is responsible for the dominant white coat colour of blue fox (Alopex lagopus).  

PubMed

The dominant white coat colour of farmed blue fox is inherited as a monogenic autosomal dominant trait and is suggested to be embryonic lethal in the homozygous state. In this study, the transcripts of KIT were identified by RT-PCR for a dominant white fox and a normal blue fox. Sequence analysis showed that the KIT transcript in normal blue fox contained the full-length coding sequence of 2919 bp (GenBank Acc. No KF530833), but in the dominant white individual, a truncated isoform lacking the entire exon 12 specifically co-expressed with the normal transcript. Genomic DNA sequencing revealed that a single nucleotide polymorphism (c.1867+1G>T) in intron 12 appeared only in the dominant white individuals and a 1-bp ins/del polymorphism in the same intron showed in individuals representing two different coat colours. Genotyping results of the SNP with PCR-RFLP in 185 individuals showed all 90 normal blue foxes were homozygous for the G allele, and all dominant white individuals were heterozygous. Due to the truncated protein with a deletion of 35 amino acids and an amino acid replacement (p.Pro623Ala) located in the conserved ATP binding domain, we propose that the mutant receptor had absent tyrosine kinase activity. These findings reveal that the base substitution at the first nucleotide of intron 12 of KIT gene, resulting in skipping of exon 12, is a causative mutation responsible for the dominant white phenotype of blue fox. PMID:24308634

Yan, S Q; Hou, J N; Bai, C Y; Jiang, Y; Zhang, X J; Ren, H L; Sun, B X; Zhao, Z H; Sun, J H

2014-04-01

55

ORIGINAL ARTICLE Estimates of annual survival, growth, and recruitment  

E-print Network

population study of white-tailed ptarmigan (Lagopus leucura), a species endemic to alpine habitats in western to determination of vital rates for breeding-age birds. Keywords Alpine Á Colorado Á Demography Á Lagopus leucura Á

Aldridge, Cameron

56

Conservation and Management Sandercock_6480004_ch21.indd 281Sandercock_6480004_ch21.indd 281 7/18/11 11:57:26 AM7/18/11 11:57:26 AM  

E-print Network

of ptarmigan populations. Key Words: climate change, genetics, Lagopus leucura, stable isotopes, temporal S. O'Donnell, and Cameron L. Aldridge Abstract. White-tailed Ptarmigan (Lagopus leu- cura) are well

Aldridge, Cameron

57

Mercury in feathers of Swedish gyrfalcons, Falco rusticolus , in relation to diet  

Microsoft Academic Search

The gyrfalcon (Falco rusticolus) is mainly a resident bird breeding in mountain areas in Fennoscandia. The population (estimated to 300-500 pairs) probably fluctuates according to the presence of willow grouse (Lagopus lagopus) and ptarmigan (Lagopus mutus). Little is known about pollutant levels in Fennoscandian gyrfalcons. Previous studies found low levels of DDE, PCB and mercury in organs from six Norwegian

Peter Lindberg

1984-01-01

58

Comparative breeding ecology of Lesser Sandhill Cranes (Grus canadensis canadensis) and Siberian cranes (G. leucogeranus) in Eastern Siberia  

E-print Network

, then migrating to coastal tundra to calve and for summer grazing (Bliss 1981, Shmatkova and Klokov 2001). Other characteristic common mammals in the area are arctic fox (Alopex lagopus), ermine (Mustela erminea), Siberian lemming (Lemmus sibiricus), collared... pugnax), Willow Ptarmigan (Lagopus lagopus), and Snow Bunting (Plectrophenax nivalis) (Pearce et al. 1998a,b). Rare falcons such as Peregrine Falcon (Falco peregrinus) and Gyrfalcon (F. rusticolus) also breed in this area (Shmatkova and Klokov 2001...

Watanabe, Tsuyoshi

2007-04-25

59

Generation of periodic waves by landscape features in cyclic predator-prey systems.  

PubMed Central

The vast majority of models for spatial dynamics of natural populations assume a homogeneous physical environment. However, in practice, dispersing organisms may encounter landscape features that significantly inhibit their movement. We use mathematical modelling to investigate the effect of such landscape features on cyclic predator-prey populations. We show that when appropriate boundary conditions are applied at the edge of the obstacle, a pattern of periodic travelling waves develops, moving out and away from the obstacle. Depending on the assumptions of the model, these waves can take the form of roughly circular 'target patterns' or spirals. This is, to our knowledge, a new mechanism for periodic-wave generation in ecological systems and our results suggest that it may apply quite generally not only to cyclic predator-prey interactions, but also to populations that oscillate for other reasons. In particular, we suggest that it may provide an explanation for the observed pattern of travelling waves in the densities of field voles (Microtus agrestis) in Kielder Forest (Scotland-England border) and of red grouse (Lagopus lagopus scoticus) on Kerloch Moor (northeast Scotland), which in both cases move orthogonally to any large-scale obstacles to movement. Moreover, given that such obstacles to movement are the rule rather than the exception in real-world environments, our results suggest that complex spatio-temporal patterns such as periodic travelling waves are likely to be much more common in the natural world than has previously been assumed. PMID:11886619

Sherratt, J A; Lambin, X; Thomas, C J; Sherratt, T N

2002-01-01

60

Environmental heterogeneity influences the reliability of secondary sexual traits as condition indicators.  

PubMed

Numerous studies have shown positive associations between ornaments and condition, as predicted by indicator models of sexual selection. However, this idea is continuously challenged by opposite results, which reveal our lack of full understanding of how sexual selection works. Environmental heterogeneity may explain such inconsistencies, but valid field tests of this idea are currently lacking. We first analysed the relationship between condition and ornament expression from nine populations over 7 years in a wild bird, the red grouse Lagopus lagopus scoticus. We then manipulated male aggressiveness at the population level by means of testosterone implants in a replicated field experiment. We found that the relationship between condition and ornamentation varied greatly between environments and became stronger when environmental conditions (ECs) were worse or when aggressiveness in the population was experimentally increased. Some ornaments may therefore reliably advertise a better condition only in adverse ECs. Considering environmental heterogeneity can help reconcile conflicting findings regarding the reliability of ornaments as indicators of condition and will help our understanding of sexual selection processes. PMID:22022806

Vergara, Pablo; Martinez-Padilla, J; Mougeot, F; Leckie, F; Redpath, S M

2012-01-01

61

Enhanced control of sheep ticks in upland sheep flocks: repercussions for red grouse co-hosts.  

PubMed

Sheep ticks Ixodes ricinus (Acari: Ixodidae) and tick-borne diseases cause major economic losses in both upland sheep farming and moorland shoots of red grouse Lagopus lagopus scoticus. Sheep were treated with acaricide four times between March and October and double-vaccinated against louping ill virus (LIV), instead of the conventional regime of two acaricide treatments and no vaccinations, on two moors in northern England. Enhanced treatment started at Westerdale Moor in 1995 and at Danby Moor in 2000; the latter had previously represented a spatial control site. From 1992 to 2003, grouse chick condition, tick burdens, reproductive success, shooting bags and LIV seroprevalence were measured. A total of 1297 grouse chicks from 398 broods were examined for ticks. Enhanced acaricide treatment reduced tick burdens by 90%, and LIV seroprevalence decreased in relation to the number of years since treatment began. Breeding success and post-breeding densities of grouse in the current sample area remained unrelated to acaricide treatment, tick burdens or LIV seroprevalence, but 25% and 60% more grouse were shot on Westerdale and Danby, respectively, after treatment enhancement than before. By improving shooting bags, tick management schemes help to maintain the economic viability of grouse moors, which, in turn, provide upland landscape and wildlife benefits. PMID:22112150

Newborn, D; Baines, D

2012-03-01

62

Parasitized mates increase infection risk for partners.  

PubMed

Individuals can gain fitness benefits and costs through their mates. However, studies on sexual selection have tended to focus on genetic benefits. A potentially widespread cost of pairing with a parasitized mate is that doing so will increase an individual's parasite abundance. Such a cost has been overlooked in systems in which parasites are indirectly transmitted. We manipulated the abundance of the nematode parasite Trichostrongylus tenuis, an indirectly transmitted parasite, within pairs of wild red grouse Lagopus lagopus scoticus in spring. Parasite levels were correlated within pairs before the experiment. We removed parasites from males, females, or both members of the pair and evaluated individual parasite uptake over the subsequent breeding period. At the end of the breeding season, an individual's parasite abundance was greater when its mate had not been initially purged of parasites. This cost appeared to be greater for males. We discuss the implications of our results in relation to the costs that parasites may have on sexual selection processes. PMID:22617268

Martinez-Padilla, Jesus; Vergara, Pablo; Mougeot, François; Redpath, Stephen M

2012-06-01

63

A model to test how ticks and louping ill virus can be controlled by treating red grouse with acaricide.  

PubMed

Ticks are the most important vectors of disease-causing pathogens in Europe. In the U.K., Ixodes ricinus L. (Ixodida: Ixodidae) transmits louping ill virus (LIV; Flaviviridae), which kills livestock and red grouse, Lagopus lagopus scoticus Lath. (Galliformes: Phasianidae), a valuable game bird. Tick burdens on grouse have been increasing. One novel method to reduce ticks and LIV in grouse may be acaricide treatment. Here, we use a mathematical model parameterized with empirical data to investigate how the acaricide treatment of grouse might theoretically control ticks and LIV in grouse. Assuming a situation in which ticks and LIV impact on the grouse population, the model predicts that grouse density will depend on deer density because deer maintain the tick population. In low deer densities, no acaricide treatment is predicted to be necessary because abundances of grouse will be high. However, at higher deer densities, the model predicts that grouse densities will increase only if high numbers of grouse are treated, and the efficacy of acaricide is high and lasts 20 weeks. The qualitative model predictions may help to guide decisions on whether to treat grouse or cull deer depending on deer densities and how many grouse can be treated. The model is discussed in terms of practical management implications. PMID:23088727

Porter, R; Norman, R A; Gilbert, L

2013-09-01

64

An alternative to killing? Treatment of reservoir hosts to control a vector and pathogen in a susceptible species.  

PubMed

Parasite-mediated apparent competition occurs when one species affects another through the action of a shared parasite. One way of controlling the parasite in the more susceptible host is to manage the reservoir host. Culling can cause issues in terms of ethics and biodiversity impacts, therefore we ask: can treating, as compared to culling, a wildlife host protect a target species from the shared parasite? We used Susceptible Infected Recovered (SIR) models parameterized for the tick-borne louping ill virus (LIV) system. Deer are the key hosts of the vector (Ixodes ricinus) that transmits LIV to red grouse Lagopus lagopus scoticus, causing high mortality. The model was run under scenarios of varying acaricide efficacy and deer densities. The model predicted that treating deer can increase grouse density through controlling ticks and LIV, if acaricide efficacies are high and deer densities low. Comparing deer treated with 70% acaricide efficacy with a 70% cull rate suggested that treatment may be more effective than culling if initial deer densities are high. Our results will help inform tick control policies, optimize the targeting of control methods and identify conditions where host management is most likely to succeed. Our approach is applicable to other host-vector-pathogen systems. PMID:22939093

Porter, R; Norman, R A; Gilbert, L

2013-02-01

65

Social context decouples the relationship between a sexual ornament and testosterone levels in a male wild bird.  

PubMed

In order to maximise fitness individuals should adjust their level of signalling according to their surrounding social environment. However, field experiments showing such adjustment of current signalling associated to changes in social context are lacking. Here, we manipulated levels of male aggressive- and dominance-related displays in a wild bird in our treated area by increasing testosterone levels using implants in a subset of males. We then compared the expression of sexual signals (i.e. comb size) between non-treated red grouse Lagopus lagopus scoticus males from control and treatment areas. We further explored the potential endocrinological mechanism linking social environment and signal expression by analysing testosterone levels in all males. Our treatment successfully increased overall aggressive- and dominance-related behaviours in the treatment area. Furthermore, testosterone-implanted birds increased their comb size as repeatedly shown in previous studies in male red grouse. Interestingly, untreated males living in the treatment area decreased their comb size, whilst increasing testosterone levels. Since comb size is a signal of dominance, untreated males from the treatment area may have perceived themselves as subordinate individuals and decreased their signalling levels to avoid confrontations with testosterone-treated, dominant individuals. In conclusion, our findings show that social context has the potential to regulate sexual signalling and testosterone levels. Our results highlight the role of social context when exploring the link between testosterone and behaviour, as it may reverse the relationship between both traits. Our results suggest that social context affects signalling and testosterone independently. PMID:22841824

Vergara, Pablo; Martínez-Padilla, Jesús

2012-09-01

66

Genet. Sel. Evol. 35 (2003) 573580 573 INRA, EDP Sciences, 2003  

E-print Network

procyonoides procyonoides), the red fox (Vulpes vulpes) and the arctic fox (Alopex lagopus)) were studied dog (Nyctereutes procyonoides procyonoides), the arctic fox (Alopex lagopus) and the red fox (Vulpes vulpes). It should be mentioned that foxes and the racoon dog are fur animals and are of an economic

Boyer, Edmond

67

Reducing tick burdens on chicks by treating breeding female grouse with permethrin  

Technology Transfer Automated Retrieval System (TEKTRAN)

Ticks are important arthropod vectors of diseases of human, livestock, and wildlife hosts. In the United Kingdom, the sheep tick (Ixodes ricinus) is increasingly recognized as a main limiting factor of red grouse (Lagopus lagopus) populations, a game bird of high economic value. We evaluated the e...

68

Effects of lead shot ingestion in willow grouse  

SciTech Connect

Willow grouse (Lagopus lagopus) is the most popular game bird in Norway and hunted extensively. Ingestion of lead shot pellets as grit with consequently adverse effects is therefore a distinct possibility as this has been observed in other upland game birds. The present experiment was carried out to study the possible effects of ingested lead shot pellets on willow grouse.

Fimreite, N.

1984-07-01

69

Cycles in voles and small game in relation to variations in plant production indices in Northern Sweden  

Microsoft Academic Search

Population dynamics for voles (Cricetidae), Tengmalm's owl (Aegolius funereus (L.)), red fox (Vulpes vulpes (L.)) willow grouse (Lagopus lagopus (L.)), black grouse (Lyrurus tetrix (L.)), capercaillie (Tetrao urogallus L.), hazel hen (Tetrastes bonasia (L.)), mountain hare (Lepus timidus L.) and tularemia (Francisella tularensis (McCoy & Chapin)) and game bird recruitment were studied by index methods in northern Sweden. In addition

B. Hörnfeldt; O. Löfgren; B.-G. Carlsson

1986-01-01

70

Intra-sexual competition alters the relationship between testosterone and ornament expression in a wild territorial bird.  

PubMed

In a reliable signalling system, individual quality is expected to mediate the costs associated with ornamental displays, with relatively lower costs being paid by individuals of higher quality. These relative costs should depend not only on individual quality, but also on levels of intra-sexual competition. We explored the current and delayed effects that testosterone implants have on bird ornamentation in populations with contrasted population densities, as a proxy for intra-sexual competition. In a replicated experiment, we manipulated testosterone in 196 yearling male red grouse Lagopus lagopus scoticus in autumn in populations of high and low levels of intra-sexual competition. Males were assigned to one of three exogenous testosterone (T) treatments: empty implants (T0), small T implants (T1) or larger T implants (T2). We monitored subsequent changes in testosterone levels, ornament size and carotenoid-based colouration, carotenoid levels and body condition from autumn to spring. Testosterone implants increased testosterone levels, comb redness and comb size, and decreased body condition but these effects depended on levels of intra-sexual competition. Specifically, T2-implanted birds increased testosterone levels and comb size more, and reduced body condition more, in populations where intra-sexual competition was low. In the following spring, testosterone levels of T2-treated birds kept increasing in populations where intra-sexual competition was high but not in populations where intra-sexual competition was low. Our results highlight that levels of intra-sexual competition alter the relationship between testosterone levels and ornament expression, influencing their condition-dependence; they also indicate that the outcome of standard hormone manipulation conducted in free-living animals vary depending on the population context. PMID:24698833

Martínez-Padilla, J; Pérez-Rodríguez, L; Mougeot, F; Ludwig, S; Redpath, S M

2014-05-01

71

Experimentally elevated levels of testosterone at independence reduce fitness in a territorial bird.  

PubMed

Environmental conditions and individual strategies in early life may have a profound effect on fitness. A critical moment in the life of an organism occurs when an individual reaches independence and stops receiving benefits from its relatives. Understanding the consequences of individual strategies at the time of independence requires quantification of their fitness effects. We explored this period in the Red Grouse (Lagopus lagopus scoticus). In this system, testosterone and parasite (Trichostrongylus tenuis) levels are known to influence survival and reproduction, the two key components of individual fitness. We experimentally and simultaneously manipulated testosterone and parasites at three levels (high, intermediate, and control levels for both factors) in 195 young males in five populations using a factorial experimental design. We explored the effects of our treatments on fitness by monitoring reproduction and survival throughout the life of all males and estimating lambda(ind), a rate-sensitive index of fitness. Parasite challenges increased the number of worms with a time lag, as previously found. However, we did not find significant effects of parasite manipulations on fitness, possibly because parasite abundance did not increase to harmful levels. Our hormone manipulation was successful at increasing testosterone at three different levels. Such increases in hormone levels decreased overall fitness. This was caused by reduced offspring production in the first breeding attempt rather than by any effect of the treatment on bird survival. Our results highlight that investing in high testosterone levels at independence, a strategy that might enhance short-term recruitment probability in territorial species such as Red Grouse, has a fitness cost, and can influence the resolution of the trade-off between reproduction and survival later in life. PMID:24933821

Martínez-Padilla, J; Pérez-Rodríguez, L; Mougeot, F; Ludwig, S C; Redpath, S M

2014-04-01

72

Habitat loss and raptor predation: disentangling long- and short-term causes of red grouse declines.  

PubMed

The number of red grouse (Lagopus lagopus scoticus) shot in the UK has declined by 50% during the 20th century This decline has coincided with reductions in the area of suitable habitat and recoveries in the populations of some avian predators. Here we use long-term records of shooting bags and a large-scale manipulation of raptor density to disentangle the effects of habitat loss and raptor predation on grouse populations. The numbers of grouse harvested on the Eskdale half of Langholm Moor in southern Scotland declined significantly during 1913-1990 and grouse bags from the whole moor from 1950 to 1990 exhibited an almost identical but non-significant trend. Hen harriers (Circus cyaneus) and peregrine falcons (Falco peregrinus) were absent or bred at low densities on this moor throughout this period but heather-dominant vegetation declined by 48% between 1948 and 1988. Harrier and peregrine breeding numbers on Langholm Moor increased to high levels following protection in 1990 whilst grouse density and grouse bags declined year after year until shooting was abandoned in 1998. The prediction of a peak in grouse bags on Langholm Moor in 1996 based on the patterns of bags during 1950-1990 was supported by the observed peaks in 1997 on two nearby moors with few raptors which formerly cycled in synchrony with Langholm Moor. This study demonstrates that, whilst long-term declines in grouse bags were most probably due to habitat loss, high levels of raptor predation subsequently limited the grouse population and suppressed a cycle. This study thus offers support to theoretical models which predict that generalist predators may suppress cycles in prey populations. PMID:10821608

Thirgood, S J; Redpath, S M; Haydon, D T; Rothery, P; Newton, I; Hudson, P J

2000-04-01

73

Habitat loss and raptor predation: disentangling long- and short-term causes of red grouse declines.  

PubMed Central

The number of red grouse (Lagopus lagopus scoticus) shot in the UK has declined by 50% during the 20th century This decline has coincided with reductions in the area of suitable habitat and recoveries in the populations of some avian predators. Here we use long-term records of shooting bags and a large-scale manipulation of raptor density to disentangle the effects of habitat loss and raptor predation on grouse populations. The numbers of grouse harvested on the Eskdale half of Langholm Moor in southern Scotland declined significantly during 1913-1990 and grouse bags from the whole moor from 1950 to 1990 exhibited an almost identical but non-significant trend. Hen harriers (Circus cyaneus) and peregrine falcons (Falco peregrinus) were absent or bred at low densities on this moor throughout this period but heather-dominant vegetation declined by 48% between 1948 and 1988. Harrier and peregrine breeding numbers on Langholm Moor increased to high levels following protection in 1990 whilst grouse density and grouse bags declined year after year until shooting was abandoned in 1998. The prediction of a peak in grouse bags on Langholm Moor in 1996 based on the patterns of bags during 1950-1990 was supported by the observed peaks in 1997 on two nearby moors with few raptors which formerly cycled in synchrony with Langholm Moor. This study demonstrates that, whilst long-term declines in grouse bags were most probably due to habitat loss, high levels of raptor predation subsequently limited the grouse population and suppressed a cycle. This study thus offers support to theoretical models which predict that generalist predators may suppress cycles in prey populations. PMID:10821608

Thirgood, S J; Redpath, S M; Haydon, D T; Rothery, P; Newton, I; Hudson, P J

2000-01-01

74

Sensitivity to assumptions in models of generalist predation on a cyclic prey.  

PubMed

Ecological theory predicts that generalist predators should damp or suppress long-term periodic fluctuations (cycles) in their prey populations and depress their average densities. However, the magnitude of these impacts is likely to vary depending on the availability of alternative prey species and the nature of ecological mechanisms driving the prey cycles. These multispecies effects can be modeled explicitly if parameterized functions relating prey consumption to prey abundance, and realistic population dynamical models for the prey, are available. These requirements are met by the interaction between the Hen Harrier (Circus cyaneus) and three of its prey species in the United Kingdom, the Meadow Pipit (Anthus pratensis), the field vole (Microtus agrestis), and the Red Grouse (Lagopus lagopus scoticus). We used this system to investigate how the availability of alternative prey and the way in which prey dynamics are modeled might affect the behavior of simple trophic networks. We generated cycles in one of the prey species (Red Grouse) in three different ways: through (1) the interaction between grouse density and macroparasites, (2) the interaction between grouse density and male grouse aggressiveness, and (3) a generic, delayed density-dependent mechanism. Our results confirm that generalist predation can damp or suppress grouse cycles, but only when the densities of alternative prey are low. They also demonstrate that diametrically opposite indirect effects between pairs of prey species can occur together in simple systems. In this case, pipits and grouse are apparent competitors, whereas voles and grouse are apparent facilitators. Finally, we found that the quantitative impacts of the predator on prey density differed among the three models of prey dynamics, and these differences were robust to uncertainty in parameter estimation and environmental stochasticity. PMID:18027760

Matthiopoulos, Jason; Graham, Kate; Smout, Sophie; Asseburg, Christian; Redpath, Stephen; Thirgood, Simon; Hudson, Peter; Harwood, John

2007-10-01

75

The relationship between foot size of wild canids and regional snow conditions: evidence for selection against a high  

E-print Network

Canis latrans (n = 472), red fox Vulpes vulpes (n = 199), arctic fox Alopex lagopus (n = 52), grey fox Urocyon cinereoargenteus (n = 17), and wolf Canis lupus (n = 14) and compared body mass, total foot area

76

Western Birds, Index, Volume 40, 2009  

E-print Network

... Oregon, 260–266 Bunting, Snow, 122, 185 Buteo jamaicensis , 78, 128, 278, 279 lagopus , 79, 210–224 ... Snowy, 97, 180 Western Screech-, 97, 128 Oxyura jamaicensis , 72 Oystercatcher, American, 172 Black, 81, 129 ...

77

Platinum Group Elements in the Feathers of Raptors and Their Prey  

Microsoft Academic Search

Platinum (Pt), palladium (Pd), and rhodium (Rh) concentrations were determined in the feathers of three raptor species in\\u000a Sweden, the sparrowhawk (Accipiter nisus), the peregrine falcon (Falco peregrinus), and the gyrfalcon (Falco rusticolus), as well as the main prey of the sparrowhawk (the house sparrow, Passer domesticus) and the gyrfalcon (the willow grouse, Lagopus lagopus).\\u000a \\u000a \\u000a \\u000a The analysis of feathers from

K. H. Jensen; S. Rauch; G. M. Morrison; P. Lindberg

2002-01-01

78

The importance of willow thickets for ptarmigan and hares in shrub tundra: the more the better?  

Microsoft Academic Search

In patchy habitats, the relationship between animal abundance and cover of a preferred habitat may change with the availability\\u000a of that habitat, resulting in a functional response in habitat use. Here, we investigate the relationship of two specialized\\u000a herbivores, willow ptarmigan (Lagopus lagopus) and mountain hare (Lepus timidus), to willows (Salix spp.) in three regions of the shrub tundra zone—northern

Dorothée Ehrich; John-André Henden; Rolf Anker Ims; Lilyia O. Doronina; Siw Turid Killengren; Nicolas Lecomte; Ivan G. Pokrovsky; Gunnhild Skogstad; Alexander A. Sokolov; Vasily A. Sokolov; Nigel Gilles Yoccoz

79

Breeding habitat selection of sympatric White-tailed, Rock and Willow Ptarmigan in the southern Yukon Territory, Canada  

Microsoft Academic Search

We examined breeding habitat selection at two scales for White-tailed (Lagopus leucura), Rock (L. muta), and Willow Ptarmigan (L. lagopus) at an alpine site in the Ruby Range Mountains of the Yukon Territory, Canada. To infer species-specific preferences, we\\u000a used logistic regression and AIC model selection to compare nest habitat of White-tailed (n = 43) and Rock Ptarmigan (n = 58). Only descriptive statistics

Scott Wilson; Kathy Martin

2008-01-01

80

Mercury in feathers of Swedish gyrfalcons, Falco rusticolus, in relation to diet  

SciTech Connect

The gyrfalcon (Falco rusticolus) is mainly a resident bird breeding in mountain areas in Fennoscandia. The population (estimated to 300-500 pairs) probably fluctuates according to the presence of willow grouse (Lagopus lagopus) and ptarmigan (Lagopus mutus). Little is known about pollutant levels in Fennoscandian gyrfalcons. Previous studies found low levels of DDE, PCB and mercury in organs from six Norwegian gyrfalcons. In this paper the author has included additional information on mercury levels, based on feather analyses from a few nests in northern Sweden. The use of feathers is a simple method to monitor mercury levels without sacrificing the birds. Food habits were checked by analyzing food remains at and near the nests.

Lindberg, P.

1984-04-01

81

Offshore marine observation of Willow Ptarmigan, including water landings, Kuskokwim Bay, Alaska  

USGS Publications Warehouse

We report an observation of Willow Ptarmigan (Lagopus lagopus) encountered 8 to 17 km from the nearest shoreline on Kuskokwim Bay, Alaska, on 30 August 2003. The ptarmigan were observed flying, landing on our research vessel, and landing and taking off from the water surface. We also report on one other observation of ptarmigan sitting on the water surface and other marine observations of ptarmigan from the North Pacific Pelagic Seabird Database. These observations provide evidence that Willow Ptarmigan are capable of dispersing across large bodies of water and landing and taking off from the water surface.

Zimmerman, C.E.; Hillgruber, N.; Burril, S.E.; St., Peters, M. A.; Wetzel, J.D.

2005-01-01

82

Serosurvey for Toxoplasma gondii in arctic foxes and possible sources of infection in the high Arctic of Svalbard  

Microsoft Academic Search

Samples (blood or tissue fluid) from 594 arctic foxes (Alopex lagopus), 390 Svalbard reindeer (Rangifer tarandus platyrhynchus), 361 sibling voles (Microtus rossiaemeridionalis), 17 walruses (Odobenus rosmarus), 149 barnacle geese (Branta leucopsis), 58 kittiwakes (Rissa tridactyla), and 27 glaucous gulls (Larus hyperboreus) from Svalbard and nearby waters were assayed for antibodies against Toxoplasma gondii using a direct agglutination test. The proportion

Kristin Wear Prestrud; Kjetil Åsbakk; Eva Fuglei; Torill Mørk; Audun Stien; Erik Ropstad; Morten Tryland; Geir Wing Gabrielsen; Christian Lydersen; Kit M. Kovacs; Maarten J. J. E. Loonen; Kjetil Sagerup; Antti Oksanen

2007-01-01

83

Serum concentrations of vitamin D metabolites, vitamins A and E, and carotenoids in six canid and four ursid species at four zoos  

Microsoft Academic Search

Nutritional status for six captive canid species (n=34) and four captive ursid species (n=18) were analyzed. The species analyzed included: African wild dog (Lycaon pictus), arctic fox (Alopex lagopus), gray wolf (Canis lupus), maned wolf (Chrysocyon brachyurus), Mexican wolf (Canis lupus baleiyi), red wolf (Canis rufus), brown bear (Ursus arctos), polar bear (Ursus maritimus), spectacled bear (Tremarctos ornatus), and sun

Susan Crissey; Kimberly Ange; Kerri Slifka; Phyllis Bowen; Maria Stacewicz-Sapuntzakis; Craig Langman; William Sadler; Ann Ward

2001-01-01

84

Geographical distribution of Pleistocene cold-adapted large mammal faunas in the Iberian Peninsula  

Microsoft Academic Search

Cold-adapted large mammal faunas reached the Iberian Peninsula during the coldest periods of the Late Pleistocene. A total of 75 Iberian sites yielded remains of the cold-adapted faunal complex which is composed of the species, Mammuthus primigenius (woolly mammoth), Coelodonta antiquitatis (woolly rhinoceros), Rangifer tarandus (reindeer) and, to a lesser extent, Gulo gulo (wolverine), Alopex lagopus (arctic fox), Ovibos moschatus

Diego J. Álvarez-Lao; Nuria García

2011-01-01

85

ORIGINAL PAPER Endoparasites in the endangered Fennoscandian population  

E-print Network

ORIGINAL PAPER Endoparasites in the endangered Fennoscandian population of arctic foxes (Vulpes /Published online: 11 February 2011 # Springer-Verlag 2011 Abstract The Fennoscandian arctic fox (Vulpes lagopus) population is endangered due to overharvest and competi- tion with the larger red fox (Vulpes

Paris-Sud XI, Université de

86

Chronological distribution of Pleistocene cold-adapted large mammal faunas in the Iberian Peninsula  

Microsoft Academic Search

During the coldest episodes of the Late Pleistocene, the cold-adapted large mammal faunas moved southward, reaching southern regions such as the Iberian Peninsula. Thus, during the Late Pleistocene, remains of Mammuthus primigenius, Coelodonta antiquitatis and Rangifer tarandus were found in Iberia. In addition, four other cold-adapted species (Gulo gulo, Alopex lagopus, Ovibos moschatus and Saiga tatarica) were present, although in

Diego J. Álvarez-Lao; Nuria García

2010-01-01

87

Persistent organochlorine levels in six prey species of the gyrfalcon Falco rusticolus in Iceland  

Microsoft Academic Search

Our previous investigations have revealed very high levels of organochlorines (OCs) in the Icelandic gyrfalcon Falco rusticolus, a resident top predator. We now examine six potential prey species of birds, both resident and migratory, in order to elucidate the most likely route of the OCs to the gyrfalcon. The ptarmigan Lagopus mutus, the most important prey of the gyrfalcon, contained

K. Ólafsdóttir; Æ. Petersen; E. V. Magnúsdóttir; T. Björnsson; T. Jóhannesson

2001-01-01

88

NESTING DOCUMENTATION FOR THE WHITE-TAILED PTARMIGAN IN THE SANGRE DE CRISTO MOUNTAINS, NEW MEXICO  

Microsoft Academic Search

The southernmost extent of the range of White-tailed Ptarmigan (Lagopus leucura) reaches into north-central New Mexico. Although known to occur in New Mexico since around 1865, their exact distribution and abundance is not well known. This is primarily because the species is an alpine obligate, which has made efforts to survey difficult. Here I describe the first nest of the

Donald H. Wolfe

89

Population structure in a critically endangered arctic fox population: does genetics matter?  

Microsoft Academic Search

The arctic fox ( Alopex lagopus ) in Scandinavia is classified as critically endangered after having gone through a severe decline in population size in the beginning of the 20th century, from which it has failed to recover despite more than 65 years of protection. Arctic foxes have a high dispersal rate and often disperse over long distances, suggesting that

L. DALÉN; K. KVALØY; J. D. C. L INNELL; B. ELMHAGEN; O. STRAND; M. TANNERFELDT; H. HENTTONEN; E. FUGLEI; A. LANDA; A. ANGERBJÖRN

2006-01-01

90

Hoarding of pulsed resources: Temporal variations in egg-caching by arctic fox  

Microsoft Academic Search

Resource pulses are common in various ecosystems and often have large impacts on ecosystem functioning. Many animals hoard food during resource pulses, yet how this behaviour affects pulse diffusion through trophic levels is poorly known because of a lack of individual-based studies. Our objective was to examine how the hoarding behaviour of arctic foxes (Alopex lagopus) preying on a seasonal

Vincent Careau; Nicolas Lecomte; Joël Bêty; Jean-François Giroux; Gilles Gauthier; Dominique Berteaux

2008-01-01

91

Surviving on cached foods - the energetics of egg-caching by arctic foxes  

Microsoft Academic Search

Food-caching by arctic foxes (Vulpes lagopus (L., 1758)) is a behavioural adaptation thought to increase winter survival, especially in bird colonies where a large number of eggs can be cached during a short nesting season. In this pa- per, we measured the energy content of greater snow goose (Chen caerulescens atlantica Kennard, 1927) eggs and eval- uated their perishability when

V. Careau; J.-F. Giroux; G. Gauthier; D. Berteaux

2008-01-01

92

Foraging Patterns of Arctic Foxes at a Large Arctic Goose Colony  

Microsoft Academic Search

Arctic foxes (Alopex lagopus) are the main predators of many arctic-nesting birds, and such predation can have a large impact on the nesting performance of geese in some years and in some parts of the Arctic. We examined foraging patterns of arctic foxes at a large lesser snow goose (Chen caerulescens caerulescens) colony on Banks Island, Canada, from 1996 to

GUSTAF SAMELIUS; RAY T. ALISAUSKAS

2000-01-01

93

vertebradosibericos.org -AVES >> Presentacin del Atlas Virtual >> Mapas de distribucin y listado de especies ATLAS VIRTUAL DE LAS AVES TERRESTRES DE ESPAA  

E-print Network

Lanius excubitor Alcaudón Real 4 3 Loxia curvirostra Piquituerto Común 66 Lullula arborea Totovía 45 2 torquilla Torcecuello 25 3 link Lagopus mutus Lagópodo Alpino 54 + Lanius collurio Alcaudón Dorsirrojo 62 3

Carrascal, Luis M.

94

Response of Predators to Western Sandpiper Nest Exclosures  

Microsoft Academic Search

In 2001, predator exclosures were used to protect nests of the Western Sandpiper ( Calidris mauri ) in western Alaska. During the exclosure experiment, nest contents in exclosures had significantly higher daily survival rates than control nests, however, late in the study predators began to cue in on exclosures and predate the nest contents. An Arctic Fox ( Alopex lagopus

A MANDA C. N IEHAUS; D ANIEL R. R UTHRAUFF; RIAN J. M C C AFFERY

95

Chromosomal evolution of the Canidae  

Microsoft Academic Search

The Giemsa-banding patterns of chromosomes from the arctic fox (Alopex lagopus), the red fox (Vulpes vulpes), the kit fox (Vulpes macrotis), and the raccoon dog (Nyctereutes procyonoides) are compared. Despite their traditional placement in different genera, the arctic fox and the kit fox have an identical chromosome morphology and G-banding pattern. The red fox has extensive chromosome arm homoeology with

R. K. Wayne; W. G. Nash; S. J. O’Brien

1987-01-01

96

Elemental characterization of wild edible plants from countryside and urban areas.  

PubMed

Thirteen elements (Na, K, Ca, Mg, Fe, Mn, Cu, Zn, Cr, Co, Cd, Ni and Pb) in 11 different wild edible plants (WEP) (Amaranthus retroflexus, Foeniculum vulgare, Cichorium intybus, Glebionis coronaria, Sonchus spp., Borago officinalis, Diplotaxis tenuifolia, Sinapis arvensis, Papaver rhoeas, Plantago lagopus and Portulaca oleracea) collected from countryside and urban areas of Bari (Italy) were determined. B.officinalis and P.rhoeas could represent good nutritional sources of Mn and Fe, respectively, as well as A.retroflexus and S.arvensis for Ca. High intake of Pb and Cd could come from P.lagopus and A.retroflexus (1.40 and 0.13mgkg(-1) FW, respectively). WEP may give a substantial contribution to the elements intake for consumers, but in some cases they may supply high level of elements potentially toxic for human health. Anyway, both ANOVA and PCA analyses have highlighted the low influence of the harvesting site on the elements content. PMID:25660854

Renna, Massimiliano; Cocozza, Claudio; Gonnella, Maria; Abdelrahman, Hamada; Santamaria, Pietro

2015-06-15

97

Pulses of movement across the sea ice: population connectivity and temporal genetic structure in the arctic fox  

Microsoft Academic Search

Lemmings are involved in several important functions in the Arctic ecosystem. The Arctic fox (Vulpes lagopus) can be divided into two discrete ecotypes: “lemming foxes” and “coastal foxes”. Crashes in lemming abundance can result\\u000a in pulses of “lemming fox” movement across the Arctic sea ice and immigration into coastal habitats in search for food. These\\u000a pulses can influence the genetic

Karin Norén; Lindsey Carmichael; Eva Fuglei; Nina E. Eide; Pall Hersteinsson; Anders Angerbjörn

2011-01-01

98

Selected radionuclides and heavy metals in skeletons of birds of prey from eastern Poland  

Microsoft Academic Search

Results of determination of 137Cs, 90Sr, 40K, 239+240Pu, and heavy metals: Mn, Zn, Pb, Cd, Ni, Cr, Co, and Cu in skeletons of 15 species of birds of prey from Eastern Poland were\\u000a presented. The greatest amounts of 137Cs and 90Sr (70 Bq\\/kg and 33 Bq\\/kg, respectively) were found in rough-legged buzzards (Buteo lagopus), winter visitors, coming from former soviet nuclear test

A. Komosa; I. Kitowski; S. Chibowski; J. Solecki; J. Orze?; P. Ró?a?ski

2009-01-01

99

Habitat Associations and Population Trends of Two Hawks in an Urbanizing Grassland Region in Colorado  

Microsoft Academic Search

Despite increasing interest in the ecological effects of urbanization, relatively little is known about its effects in grasslands. We examined population trends and habitat associations of two predators, the rough-legged hawk (Buteo lagopus) and the red-tailed hawk (B. jamaicensis), in a rapidly urbanizing grassland region at the western edge of the North American Great Plains. Count data indicate that rough-legged

Eric Schmidt; Carl E. Bock

2005-01-01

100

Isolation of a Mycoplasma sp. from three buzzards (Buteo spp.).  

PubMed

Mycoplasma spp. were isolated from the respiratory tissues of three buzzards. Bird I, a rough-legged buzzard (Buteo lagopus), showed airsacculitis, catarrhal-fibrinous pneumonia, and catarrhal tracheitis. Bird II, a common buzzard (Buteo buteo), revealed mycotic airsacculitis, bronchitis and pneumonia. Bird III was a healthy rough-legged buzzard. All isolates metabolized glucose but not arginine and were serologically identical by immunofluorescence and growth-inhibition tests. No serological cross-reactions were seen with several known Mycoplasma species. PMID:7049150

Bölske, G; Mörner, T

1982-01-01

101

Opmerkelijke Ruigpootbuizerdinvasie in de winter 2010-2011: oorzaken in een historische en Europese context  

Microsoft Academic Search

Notable invasion of Rough Legged-buzzards in winter 2010-2011: circumstances in an historical and European context In the winter 2010 – 2011, never before seen numbers of Rough-legged Buzzards Buteo lagopus were observed in Flanders. A strong invasion of this normally scarce over-wintering species of rugged open ground occurred which also did not pass unnoticed elsewhere in Europe. This article thoroughly

W. Vansteelant; W. Faveyts; J. Buckens

2011-01-01

102

HAWKS IN NEW JERSEY  

Microsoft Academic Search

We compiled Christmas Bird Count data on Rough-legged Hawk (Buteo lagopus) numbers from New Jersey for 1954 to 1989. Analysis state-wide revealed patterns not formerly observed on the continental or local scales. Major concentrations of wintering Rough-legged Hawks were along coastal areas in southern New Jersey. This abundance pattern was positively correlated with county wetland percentage and number of frost-free

THOMAS BOSAKOWSKI; DWIGHT G. SMITH

103

Fatal pox infection in a rough-legged hawk.  

PubMed

Natural pox infection occurred in a free-living rough-legged hawk (Buteo lagopus) in northeastern North Dakota. Gross, histological and electron microscopic findings were typical of pox infection, and characteristic lesions developed in red-tailed hawks (Buteo jamaicensis) but not in great horned owls (Bubo virginianus) following inoculation with case material. Death of the rough-legged hawk was attributed to starvation rsulting from inability to capture prey and to blood loss from foot lesions. PMID:167207

Pearson, G L; Pass, D A; Beggs, E C

1975-04-01

104

Life-history and demographic variation in an alpine specialist at the latitudinal extremes of the range  

Microsoft Academic Search

Alpine environments are unique systems to examine variation in life-history strategies because temperature and seasonality\\u000a are similar across broad latitudinal gradients. We studied the life-history strategies, demography and population growth of\\u000a white-tailed ptarmigan Lagopus leucura, an alpine specialist, at the latitudinal extremes of the range in the Yukon (YK, studied from 2004 to 2008) and Colorado\\u000a (CO, 1987–1996). The two

Scott Wilson; Kathy Martin

2011-01-01

105

Mortality of arctic fox pups in northern Alaska  

SciTech Connect

Reports of mortality among arctic foxes, Alopex lagopus, generally consist of isolated incidents of predation by bald eagles, Haliaeetus leucocephalus, snowy owls, Nyctea scandiaca, red foxes, Vulpes vulpes, and dogs, Canis familiaris. This is a report of observations made on mortality of arctic fox pups observed at dens in the Prudhoe Bay and Colville River Delta areas of northern Alaska during summers of 1975 to 1978 and 1976 to 1979, respectively.

Not Available

1982-01-01

106

Fatal pox infection in a rough-legged hawk  

USGS Publications Warehouse

Natural pox infection occurred in a free-living rough-legged hawk (Buteo lagopus) in northeastern North Dakota. Gross, histological and electron microscopic findings were typical of pox infection, and characteristic lesions developed in red-tailed hawks (Buteo jamaicensis) but not in great horned owls (Bubo virginianus) following inoculation with case material. Death of the rough-legged hawk was attributed to starvation resulting from inability to capture prey and to blood loss from foot lesions.

Pearson, G.L.; Pass, D.A.; Beggs, E.C.

1975-01-01

107

Investigating variation in the nutritional ecology and genetics of White-tailed Ptarmigan: implications for climate change  

Microsoft Academic Search

White-tailed Ptarmigan (Lagopus leucura) are well suited as a focal species for the study of climate change because they are adapted to cool, alpine environments that are expected to undergo unusually rapid climate change. We compared samples collected in the late 1930s, the late 1960s, and the late 2000s using molecular genetic and stable isotope methods in an effort to

S. J. Oyler-McCance; C. A. Stricker; C. E. Braun; G. T. Wann; C. L. Aldridge

2010-01-01

108

Sarcocystis sp. from white-fronted goose ( Anser albifrons ): cyst morphology and life cycle studies  

Microsoft Academic Search

An experiment was carried out using three cubs of the arctic fox (Alopex lagopus). Twenty-five-day-old cubs were infected by feeding them with the leg muscles of the white-fronted goose (Anser albifrons) containing Sarcocystis sp. (cyst type III) cysts. Under the light microscope, the cysts were ribbon-shaped up to 4 mm long and up to 750 ?m wide. On the surface of the

L. Kutkien?; A. Sruoga; D. Butkauskas

2006-01-01

109

Sex-biased costs in nest defence behaviours by lesser snow geese ( Chen caerulescens ): consequences of parental roles?  

Microsoft Academic Search

Nest defence behaviours, such as attacking predators and defending against predator attacks, expose birds to risk of injury\\u000a and death. However, direct costs of such behaviours are poorly documented. To evaluate potential costs of nest defence behaviours\\u000a in lesser snow geese (Chen caerulescens), we (1) estimated the proportion of interactions between arctic foxes (Alopex lagopus) and geese that resulted in

Gustaf Samelius; Ray T. Alisauskas

2006-01-01

110

FATAL POX INFECTION IN A ROUGH-LEGGED HAWK  

Microsoft Academic Search

Natural pox infection occurred in a free-living rough-legged hawk (Btiieo lagopus) in northeastern North Dakota. Gross, histological and electron micro- scopic findings were typical of pox infection, and characteristic lesions developed in red-tailed hawks (Buteo jamaicensis) but not in great horned owls (Bubo s'irgini- anus) following inoculation with case material. Death of the rough-legged hawk was attributed to starvation resulting

G. L. PEARSON; D. A. PASSI; E. C. BEGGS

1975-01-01

111

Enhancement of local species richness in tundra by seed dispersal through guts of muskox and barnacle goose  

Microsoft Academic Search

The potential contribution of vertebrate-mediated seed rain to the maintenance of plant community richness in a High Arctic\\u000a ecosystem was investigated. We analyzed viable seed content in dung of the four numerically most important terrestrial vertebrates\\u000a in Northeast Greenland – muskox (Ovibos moschatus), barnacle goose (Branta leucopsis), Arctic fox (Alopex lagopus) and Arctic hare (Lepus arcticus). High numbers of plant

Hans Henrik Bruun; Rebekka Lundgren; Marianne Philipp

2008-01-01

112

Human-behavioral and paleoecological implications of terminal Pleistocene fox remains at the Marmes Site (45FR50), eastern Washington state, USA  

NASA Astrophysics Data System (ADS)

Examination of terminal Pleistocene-age fox remains from the Marmes archaeological site in southeastern Washington State (USA) reveals that a previous identification of one specimen as arctic fox (Vulpes lagopus) was incorrect. Of nearly four-dozen associated specimens, eleven, including the one originally identified as arctic fox, represent red fox (Vulpes vulpes). Cut-marked fox bones and associated stone artifacts and eyed bone needles suggest several foxes were butchered and perhaps hides sewn together. The modern environmental setting of the Marmes site is too warm for modern red fox; the prehistoric red fox remains suggest (summer) climate was cooler when those remains were deposited.

Lyman, R. Lee

2012-05-01

113

Pholeter anterouterus Fischthal & Nasir, 1974 (Digenea: Opisthorchiidae) redescribed, together with remarks on the genera Pholeter Odhner, 1914 and Phocitrema Goto & Ozaki, 1930 and their relationship to the centrocestine heterophyids.  

PubMed

Photoleter anterouterus Fischthal & Nasir, 1974, from Pelecanus occidentalis Linnaeus and Pelecanus erythrorhynchos Gmelin from Florida, USA and the ventro-genital complexes of Photeleter gastrophilus (Kossack, 1910) from Delphinus delphis Linnaeus from Queensland, Australia and of Phocitrema fusiforme Goto & Ozaki, 1930 from Alopex lagopus (Linnaeus) and Phoca vitulina Linnaeus from Alaska are redescribed. The genus Photoleter Odhner, 1914 is emended and compared with Phocitrema Goto & Ozaki, 1930 and both genera are compared with members of, and as a result transferred from the family Opisthorchiidae Looss, 1899 to, the subfamily Centrocestinae Looss, 1899, family Heterophyidae Odhner, 1914. PMID:876682

Pearson, J C; Courtney, C H

1977-06-01

114

Adoption in rock and white-tailed ptarmigan  

USGS Publications Warehouse

Reports of adoption in birds are widespread, but few studies report rates of adoption or possible mechanisms for this phenomenon, particularly in the Order Galliformes. We report incidents of adoption in Rock Ptarmigan (Lagopus muta) and White-tailed Ptarmigan (L. leucura) from two sites in western Canada. Adoption rates for White-tailed Ptarmigan on Vancouver Island, British Columbia, and the Ruby Ranges, Yukon Territory were 13% (n = 16 broods) and 4% (n = 27), respectively, while rates for Rock Ptarmigan were 14% (n = 29) in the Ruby Ranges. Low brood densities may result in lower rates of adoption for ptarmigan. ?? 2009 The Wilson Ornithological Society.

Wong, M.M.L.; Fedy, B.C.; Wilson, S.; Martin, K.M.

2009-01-01

115

From 'third pole' to north pole: a Himalayan origin for the arctic fox.  

PubMed

The 'third pole' of the world is a fitting metaphor for the Himalayan-Tibetan Plateau, in allusion to its vast frozen terrain, rivalling the Arctic and Antarctic, at high altitude but low latitude. Living Tibetan and arctic mammals share adaptations to freezing temperatures such as long and thick winter fur in arctic muskox and Tibetan yak, and for carnivorans, a more predatory niche. Here, we report, to our knowledge, the first evolutionary link between an Early Pliocene (3.60-5.08 Myr ago) fox, Vulpes qiuzhudingi new species, from the Himalaya (Zanda Basin) and Kunlun Mountain (Kunlun Pass Basin) and the modern arctic fox Vulpes lagopus in the polar region. A highly hypercarnivorous dentition of the new fox bears a striking resemblance to that of V. lagopus and substantially predates the previous oldest records of the arctic fox by 3-4 Myr. The low latitude, high-altitude Tibetan Plateau is separated from the nearest modern arctic fox geographical range by at least 2000 km. The apparent connection between an ancestral high-elevation species and its modern polar descendant is consistent with our 'Out-of-Tibet' hypothesis postulating that high-altitude Tibet was a training ground for cold-environment adaptations well before the start of the Ice Age. PMID:24920475

Wang, Xiaoming; Tseng, Zhijie Jack; Li, Qiang; Takeuchi, Gary T; Xie, Guangpu

2014-07-22

116

Sarcocystis sp. from white-fronted goose (Anser albifrons): cyst morphology and life cycle studies.  

PubMed

An experiment was carried out using three cubs of the arctic fox (Alopex lagopus). Twenty-five-day-old cubs were infected by feeding them with the leg muscles of the white-fronted goose (Anser albifrons) containing Sarcocystis sp. (cyst type III) cysts. Under the light microscope, the cysts were ribbon-shaped up to 4 mm long and up to 750 microm wide. On the surface of the wall (up to 2.4 microm), they had teat- or finger-like villar protrusions. Ultrastructurally, the cyst wall was a type-9 with villar protrusions (up to 2.3 microm long) different in size. The 11.4x1.7 (10.0-13.5x1.5-2.5)microm cystozoites were almost straight and shuttle-shaped. The fox cubs started shedding typical 12.0x8.0 (10.0-12.8x6.8-8.6)microm Sarcocystis sp. sporocysts on the 13th-14th days post-infection. The patent period lasted 19 days. The conclusion drawn was that the arctic fox (A. lagopus) can be one of the definitive hosts of Sarcocystis sp. (cyst type III) from the white-fronted goose. PMID:16649036

Kutkiene, L; Sruoga, A; Butkauskas, D

2006-10-01

117

Molecular phylogeny of grouse: individual and combined performance of W-linked, autosomal, and mitochondrial loci.  

PubMed

The phylogeny of grouse (Aves: Tetraoninae) was reconstructed using four noncoding loci: two were W-linked, one was autosomal, and one was the mitochondrial control region (CR). The rapidly evolving CR provided resolution throughout the tree, whereas the slowly evolving nuclear loci failed to resolve deeper nodes. The tree based on all four loci combined was almost identical to the CR tree and did not improve resolution or bootstrap support. The stemminess and imbalance of the trees were good determinants of the quality of the phylogenetic signal. The skewness of the tree score distribution (g(1)) behaved contrary to prediction; loci that had a more symmetric tree score distribution produced trees that had greater stemminess and balance. The quality of the phylogenetic signal was related to the evolutionary rate. Four clades of grouse were discovered. Two of these clades corresponded to currently recognized genera Bonasa and Lagopus. Bonasa was the sister to other grouse and Lagopus was the sister to the other two non-Bonasa clades. The third clade included Falcipennis, Tetrao, and Lyrurus. The fourth clade included the genera Centrocercus, Dendragapus, and Tympanuchus. The data support recognition of Falcipennis canadensis franklinii and Dendragapus obscurus fuliginosus as species. PMID:12554459

Drovetski, Sergei V

2002-12-01

118

Lesions associated with Pasteurella multocida infection in raptors.  

PubMed

Several case reports attest to the pathogenicity of Pasteurella multocida in raptors; however, the pathologic syndromes have not been fully described. We describe here the lesions encountered in 22 avian cholera cases in raptors. Besides septicemia-related lesions, a unique syndrome of esophageal abscesses was noted in 8 of the 11 (73%) Buteo hawks that succumbed to avian cholera. Esophageal abscesses were not noted in birds belonging to the order Strigiformes (owls) or family Falconidae (falcons and their relatives). Thus, the presence of white plaques in both the oropharynx and esophagus of Buteo hawks may indicate a possible P. multocida infection and should be considered in the differential diagnosis. This study also documents the first cases of avian cholera in a rough-legged hawk (Buteo lagopus) and a flammulated owl (Otus flammeolus). PMID:9087338

Morishita, T Y; Lowenstine, L J; Hirsh, D C; Brooks, D L

1997-01-01

119

Capturing migration phenology of terrestrial wildlife using camera traps  

USGS Publications Warehouse

Remote photography, using camera traps, can be an effective and noninvasive tool for capturing the migration phenology of terrestrial wildlife. We deployed 14 digital cameras along a 104-kilometer longitudinal transect to record the spring migrations of caribou (Rangifer tarandus) and ptarmigan (Lagopus spp.) in the Alaskan Arctic. The cameras recorded images at 15-minute intervals, producing approximately 40,000 images, including 6685 caribou observations and 5329 ptarmigan observations. The northward caribou migration was evident because the median caribou observation (i.e., herd median) occurred later with increasing latitude; average caribou migration speed also increased with latitude (r2 = .91). Except at the northernmost latitude, a northward ptarmigan migration was similarly evident (r2 = .93). Future applications of this method could be used to examine the conditions proximate to animal movement, such as habitat or snow cover, that may influence migration phenology.

Tape, Ken D.; Gustine, David D.

2014-01-01

120

Mortality of arctic fox pups in northern Alaska  

SciTech Connect

Reports of mortality among arctic foxes, Alopex lagopus, generally consist of isolated incidents of predation by bald eagles, Haliaeetus leucocephalus, snowy owls, Nyctea scandiaca, red foxes, Vulpes vulpes, and dogs, Canis familiaris. This is a report of observations made on mortality of arctic fox pups observed at dens in the Prudhoe Bay and Colville River Delta areas of northern Alaska during summers of 1975 to 1978 and 1976 to 1979, respectively. Pup mortality was noted amng 15 (19%) of 79 families whose dens we visited. Evidence of at least 20 dead pups was found with remains ranging from intact carcasses to a few bone fragments and tufts of hair. Undoubtedly, researchers failed to detect some dead pups, as predators sometimes carry small pups away from the den before consuming them and adult foxes were observed to dispose of bodies of dead pups within den burrows.

Garrott, R.A. (Los Alamos National Lab., NM); Eberhardt, L.E.

1982-01-01

121

Understanding sex differences in the cost of terrestrial locomotion  

PubMed Central

Little is known regarding the physiological consequences of the behavioural and morphological differences that result from sexual selection in birds. Male and female Svalbard rock ptarmigans (Lagopus muta hyperborea) exhibit distinctive behavioural differences during the breeding season. In particular, males continuously compete for and defend territories in order to breed successfully, placing large demands on their locomotor system. Here, we demonstrate that male birds have improved locomotor performance compared with females, showing both a lower cost of locomotion (CoL) and a higher top speed. We propose that the observed sex differences in locomotor capability may be due to sexual selection for improved male performance. While the mechanisms underlying these energetic differences are unclear, future studies should be wary when pooling male and female data. PMID:21849317

Lees, John J.; Nudds, Robert L.; Folkow, Lars P.; Stokkan, Karl-Arne; Codd, Jonathan R.

2012-01-01

122

Two new species of coccidia, Eimeria leucuri and E. oreoecetes (Protozoa: Eimeriidae), in grouse from Colorado.  

PubMed

Eimeria leucuri is described from white-tailed ptarmigan (Lagopus leucurus), and E. oreoecetes from white-tailed ptarmigan and blue grouse (Dendragapus obscurus) from Colorado. Oocysts of E. leucuri are ellipsoidal, 26.6 by 17.7 micron, each bearing a micropyle, micropyle cap, up to 4 polar granules, but no oocyst residuum. The lemon-shaped sporocysts are 15.4 by 6.7 micron, and have Stieda bodies and large amounts of sporocyst residuum. The sporocyst contents are enclosed in a membrane. Oocysts of E. oreoecetes are subspherical, 26.0 by 22.6 micron, and have up to 4 polar granules. The lemon-shaped sporocysts are 14.6 by 8.8 micron, and have both Stieda bodies and substiedal bodies and a large amount of sporocyst residuum. The sporocyst contents are enclosed in a membrane. These are the first coccidia to be described from these tetraonids. PMID:448611

Stabler, R M; Haskins, A G; Kitzmiller, N J; Olsen, O W; Braun, C E

1979-04-01

123

[Immunodiffusion analysis of plasma proteins in the canine family].  

PubMed

Immunodiffusion studies have been made on the plasma of 9 species (Vulpes vulpes, V. corsak, Alopex lagopus, Canis aureus, C. lupus, C. familiaris, C. dingo, Nyctereutes procynoides, Fennecus zerde) from the family of Canidae using milk antisera. Unlike rabbit antisera used earlier, milk antisera make it possible to detect more significant antigenic divergency with respect to 5 alpha- and beta-globulins. These globulins seem to have a higher evolution rate of antigenic mosaics as compared to other plasma proteins in the family investigated. The family Canidae serologically may be divided into two main groups: 1) the genus Canis which includes the wolf, domestic dog, dingo, jackal and 2) species which significantly differ from the former (the fox, polar fox, dog fox, fennec). In relation to these two groups, the raccoon dog occupies special position. PMID:62473

Baranov, O K; Iurishina, N A; Savina, M A

1976-01-01

124

Distribution of Ground-Nesting Marine Birds Along Shorelines in Glacier Bay, Southeastern Alaska: An Assessment Related to Potential Disturbance by Back-Country Users  

USGS Publications Warehouse

With the exception of a few large colonies, the distribution of ground-nesting marine birds in Glacier Bay National Park in southeastern Alaska is largely unknown. As visitor use increases in back-country areas of the park, there is growing concern over the potential impact of human activities on breeding birds. During the 2003i??05 breeding seasons, the shoreline of Glacier Bay was surveyed to locate ground-nesting marine birds and their nesting areas, including wildlife closures and historical sites for egg collection by Alaska Native peoples. The nesting distribution of four common ground-nesting marine bird species was determined: Arctic Tern (Sterna paradisaea), Black Oystercatcher (Haematopus bachmani), Mew Gull (Larus canus), and Glaucous-winged Gull (Larus glaucescens). Observations of less abundant species also were recorded, including Herring Gull (Larus argentatus), Red-throated Loon (Gavia stellata), Canada Goose (Branta canadensis), Willow Ptarmigan (Lagopus lagopus), Semipalmated Plover (Charadrius semipalmatus), Spotted Sandpiper (Actitis macularia), Least Sandpiper (Calidris minutilla), Parasitic Jaeger (Stercorarius parasiticus), and Aleutian Tern (Sterna aleutica). Nesting distribution for Arctic Terns was largely restricted to the upper arms of the bay and a few treeless islets in the lower bay, whereas Black Oystercatchers were more widely distributed along shorelines in the park. Mew Gulls nested throughout the upper bay in Geikie Inlet and in Fingers and Berg Bays, and most Glaucous-winged Gull nests were found at wildlife closures in the central and lower bays. Several areas were identified where human disturbance could affect breeding birds. This study comprises the first bay-wide survey for the breeding distribution of ground-nesting marine birds in Glacier Bay National Park, providing a minimum estimate of their numbers and distribution within the park. This information can be used to assess future human disturbance and track natural changes in nesting bird distribution over time.

Arimitsu, M.L.; Piatt, J.F.; Romano, Marc D.

2007-01-01

125

Inferring the nature of anthropogenic threats from long-term abundance records.  

PubMed

Diagnosing the processes that threaten species persistence is critical for recovery planning and risk forecasting. Dominant threats are typically inferred by experts on the basis of a patchwork of informal methods. Transparent, quantitative diagnostic tools would contribute much-needed consistency, objectivity, and rigor to the process of diagnosing anthropogenic threats. Long-term census records, available for an increasingly large and diverse set of taxa, may exhibit characteristic signatures of specific threatening processes and thereby provide information for threat diagnosis. We developed a flexible Bayesian framework for diagnosing threats on the basis of long-term census records and diverse ancillary sources of information. We tested this framework with simulated data from artificial populations subjected to varying degrees of exploitation and habitat loss and several real-world abundance time series for which threatening processes are relatively well understood: bluefin tuna (Thunnus maccoyii) and Atlantic cod (Gadus morhua) (exploitation) and Red Grouse (Lagopus lagopus scotica) and Eurasian Skylark (Alauda arvensis) (habitat loss). Our method correctly identified the process driving population decline for over 90% of time series simulated under moderate to severe threat scenarios. Successful identification of threats approached 100% for severe exploitation and habitat loss scenarios. Our method identified threats less successfully when threatening processes were weak and when populations were simultaneously affected by multiple threats. Our method selected the presumed true threat model for all real-world case studies, although results were somewhat ambiguous in the case of the Eurasian Skylark. In the latter case, incorporation of an ancillary source of information (records of land-use change) increased the weight assigned to the presumed true model from 70% to 92%, illustrating the value of the proposed framework in bringing diverse sources of information into a common rigorous framework. Ultimately, our framework may greatly assist conservation organizations in documenting threatening processes and planning species recovery. Inferencia la Naturaleza de las Amenazas Antropogénicas para los Registros de Abundancia a Largo Plazo. PMID:25065712

Shoemaker, Kevin T; Akçakaya, H Resit

2015-02-01

126

Platinum group elements in the feathers of raptors and their prey.  

PubMed

Platinum (Pt), palladium (Pd), and rhodium (Rh) concentrations were determined in the feathers of three raptor species in Sweden, the sparrowhawk ( Accipiter nisus), the peregrine falcon ( Falco peregrinus), and the gyrfalcon ( Falco rusticolus), as well as the main prey of the sparrowhawk (the house sparrow, Passer domesticus) and the gyrfalcon (the willow grouse, Lagopus lagopus). The analysis of feathers from 1917-1999 revealed a clear temporal trend, with significantly higher Rh concentrations in sparrowhawk and peregrine falcon after 1986. There is evidence for increasing platinum group element (PGE) concentrations from 1917 to 1999 in peregrine falcon and sparrowhawk. This suggests that feathers reflect increased PGE concentrations in the environment over this time period. Mean concentrations of PGE in feathers of raptors after 1986 ranged from 0.3 to 1.8 ng x g(-1) for Pt, 0.6 to 2.1 ng x g(-1) for Pd (indicative values), and 0.1 to 0.6 ng x g(-1) for Rh. House sparrows in urban areas had significantly higher Pt and Pd concentrations than urban sparrowhawks. The higher Pd concentrations in relation to Pt and Rh may indicate the greater mobility of Pd in the environment. Although PGE concentrations are generally higher in birds living in urban areas, no significant spatial trend could be established. This is partly due to the widespread distribution of automobiles and partly because birds forage and integrate PGE exposure over large areas. Laser ablation analysis demonstrates that PGE contamination of feathers is predominantly external, consisting of small particles in the nanometer size range. Other indications of external contamination are that Pt and Pd levels are significantly higher in the vane than in the shaft and that PGE relative ratios (except Pd) reflect urban particles. PMID:11910463

Jensen, K H; Rauch, S; Morrison, G M; Lindberg, P

2002-04-01

127

Is hunting mortality additive or compensatory to natural mortality? Effects of experimental harvest on the survival and cause-specific mortality of willow ptarmigan.  

PubMed

1. The effects of harvest on the annual and seasonal survival of willow ptarmigan Lagopus lagopus L. were tested in a large-scale harvest experiment. Management units were randomly assigned to one of three experimental treatments: 0%, 15% or 30% harvest. Seasonal quotas were based on the experimental treatment and estimates of bird density before the hunting season. Survival rates and hazard functions for radio-marked ptarmigan were then estimated under the competing risks of harvest and natural mortality. 2. The partially compensatory mortality hypothesis was supported: annual survival of ptarmigan was 0·54 ± 0·08 SE under 0% harvest, 0·47 ± 0·06 under 15% harvest, and was reduced to 0·30 ± 0·05 under 30% harvest. Harvest mortality increased linearly from 0·08 ± 0·05, 0·27 ± 0·05 and 0·42 ± 0·06 from 0% to 30% harvest, whereas natural mortality was 0·38 ± 0·08, 0·25 ± 0·05 and 0·28 ± 0·06 under the same treatments. 3. Realized risk of harvest mortality was 0·08-0·12 points higher than our set harvest treatments of 0-30% because birds were exposed to risk if they moved out of protected areas. The superadditive hypothesis was supported because birds in the 30% harvest treatment had higher natural mortality during winter after the hunting season. 4. Natural mortality was mainly because of raptor predation, with two seasonal peaks in fall and spring. Natural and harvest mortality coincided during early autumn with little potential for compensation during winter months. Peak risk of harvest mortality was 5× higher than natural mortality. Low natural mortality during winter suggests that most late season harvest would be additive mortality. 5. Environmental correlates of natural mortality of ptarmigan included seasonal changes in snow cover, onset of juvenile dispersal, and periods of territorial activity. Natural mortality of ptarmigan was highest during autumn movements and nesting by gyrfalcons Falco rusticolus L. Mortality was low when gyrfalcons had departed for coastal wintering sites, and during summer when ptarmigan were attending nests and broods. 6. Our experimental results have important implications for harvest management of upland gamebirds. Seasonal quotas based on proportional harvest were effective and should be set at ? 15% of August populations for regional management plans. Under threshold harvest of a reproductive surplus, 15% harvest would be sustainable at productivity rates ? 2·5 young per pair. Impacts of winter harvest could be minimized by closing the hunting season in early November or by reducing late season quotas. PMID:21054381

Sandercock, Brett K; Nilsen, Erlend B; Brøseth, Henrik; Pedersen, Hans C

2011-01-01

128

Gull eggs--food of high organic pollutant content?  

PubMed

A wide range and occasionally high levels of persistent organic pollutants (POPs) are reported in Arctic regions, especially among top predators. Polar bears (Ursus maritimus), arctic foxes (Alopex lagopus) and some gull species (Larus spp.) often have high levels of these fat-soluble pollutants. Gulls deposit significant levels of these contaminants in their eggs. In northern regions, gull eggs are part of the traditional human diet. In the present study we have investigated the levels of POPs in gull eggs in order to determine the tolerable weekly intake (TWI) for humans. Concentrations of polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were measured in 214 gull eggs collected in the spring of 2001-02. The eggs were collected from four gull species (herring gulls (Larus argentatus), great black-backed gulls (L. marinus), lesser black-backed gulls (L. fuscus) and glaucous gulls (L. hyperboreus)) at 12 different locations in Northern Norway, on the Faroe Islands and on Svalbard. The pollutant levels in gull eggs were found to be 65.5 +/- 26.9 pg toxic equivalent (TE) for dioxin and PCB g(-1) wet weight. Based on these findings and the TWI-value determined by the EU Scientific Committee on Food it is advised that children, young women and pregnant and nursing women should not eat gull eggs. Other people should limit their intake of eggs to an absolute minimum, considering the health risks associated with gull egg intake. PMID:15931427

Pusch, Kerstin; Schlabach, Martin; Prinzinger, Roland; Wing Gabrielsen, Geir

2005-06-01

129

Serosurvey for Toxoplasma gondii in arctic foxes and possible sources of infection in the high Arctic of Svalbard.  

PubMed

Samples (blood or tissue fluid) from 594 arctic foxes (Alopex lagopus), 390 Svalbard reindeer (Rangifer tarandus platyrhynchus), 361 sibling voles (Microtus rossiaemeridionalis), 17 walruses (Odobenus rosmarus), 149 barnacle geese (Branta leucopsis), 58 kittiwakes (Rissa tridactyla), and 27 glaucous gulls (Larus hyperboreus) from Svalbard and nearby waters were assayed for antibodies against Toxoplasma gondii using a direct agglutination test. The proportion of seropositive animals was 43% in arctic foxes, 7% in barnacle geese, and 6% (1 of 17) in walruses. There were no seropositive Svalbard reindeer, sibling voles, glaucous gulls, or kittiwakes. The prevalence in the arctic fox was relatively high compared to previous reports from canid populations. There are no wild felids in Svalbard and domestic cats are prohibited, and the absence of antibodies against T. gondii among the herbivorous Svalbard reindeer and voles indicates that transmission of the parasite by oocysts is not likely to be an important mechanism in the Svalbard ecosystem. Our results suggest that migratory birds, such as the barnacle goose, may be the most important vectors bringing the parasite to Svalbard. In addition to transmission through infected prey and carrion, the age-seroprevalence profile in the fox population suggests that their infection levels are enhanced by vertical transmission. PMID:17950534

Prestrud, Kristin Wear; Asbakk, Kjetil; Fuglei, Eva; Mørk, Torill; Stien, Audun; Ropstad, Erik; Tryland, Morten; Gabrielsen, Geir Wing; Lydersen, Christian; Kovacs, Kit M; Loonen, Maarten J J E; Sagerup, Kjetil; Oksanen, Antti

2007-11-30

130

Sarcoptic mange in Swedish wildlife.  

PubMed

Mange caused by Sarcoptes scabiei var. vulpes appeared among red foxes (Vulpes vulpes) in Scandinavia (south-west Finland) for the first time in this century in 1967. The disease was most probably introduced by foxes crossing the Gulf of Finland from Estonia. The mange epizootic spread northwards through Finland and reached Sweden in late 1975, when mangy foxes appeared in the northern part of the country. In 1984, mange was observed in most parts of Sweden. The disease was observed to spread rapidly in boreal areas, whereas it spread more slowly in agricultural areas. Mortality due to mange was very high. The duration of the disease before death due to emaciation has been shown experimentally to be over 90 days. An outbreak of fox mange among Arctic foxes (Alopex lagopus) occurred in 1986. The local population of Arctic foxes was caught and successfully treated. The following year, treated foxes were caught again and no signs of disease were found. Sporadic cases of fox mange have also been diagnosed in lynx (Lynx lynx), pine marten (Martes martes) and domestic dogs. Single cases have been observed in other species: wolf (Canis lupus), mountain hare (Lepus timidus), domestic cat and horse. No cases of sarcoptic mange have been recorded in the badger (Meles meles). At present, although fox mange occurs as an epizootic in local populations, the number of foxes has increased again in many parts of Sweden. PMID:1305857

Mörner, T

1992-12-01

131

Serum lipid concentrations in six canid and four ursid species in four zoos.  

PubMed

Serum lipid levels were measured in healthy captive wild canids and ursids, and the values were compared with previously published data. Serum lipid levels were evaluated in blood samples collected from eight African wild dogs (Lycaon pictus), three arctic foxes (Alopex lagopus), nine gray wolves (Canis lupus), four maned wolves (Chrysocyon brachyurus), two Mexican wolves (Canis lupus baleiyi), nine red wolves (Canis rufus), two brown bears (Ursus arctos), six polar bears (Ursus maritimus), six spectacled bears (Tremarctos ornatus), and five sun bears (Ursus malayanus). Samples were analyzed for total cholesterol, triacylglycerides, high-density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol. Although the results showed a great variation among species, circulating lipids appeared especially high, sometimes extremely so, in the spectacled bears, polar bears, sun bears, and maned wolves compared with all other species sampled. The study provides a substantial basis for comparing lipid levels in presumed healthy animals and indicates a need for controlled study of the effects of diet on circulating lipid levels. PMID:15193071

Crissey, Susan D; Ange, Kimberly D; Slifka, Kerri A; Sadler, William; Kahn, Stephen; Ward, Ann M

2004-03-01

132

Serum concentrations of vitamin D metabolites, vitamins A and E, and carotenoids in six canid and four ursid species at four zoos.  

PubMed

Nutritional status for six captive canid species (n=34) and four captive ursid species (n=18) were analyzed. The species analyzed included: African wild dog (Lycaon pictus), arctic fox (Alopex lagopus), gray wolf (Canis lupus), maned wolf (Chrysocyon brachyurus), Mexican wolf (Canis lupus baleiyi), red wolf (Canis rufus), brown bear (Ursus arctos), polar bear (Ursus maritimus), spectacled bear (Tremarctos ornatus), and sun bear (Ursus malayanus). Diet information was collected for these animals from each participating zoo (Brookfield Zoo, Fort Worth Zoo, Lincoln Park Zoological Gardens, and North Carolina Zoological Park). The nutritional composition of the diet for each species at each institution met probable dietary requirements. Blood samples were collected from each animal and analyzed for vitamin D metabolites 25(OH)D and 1,25(OH)(2)D, vitamin A (retinol, retinyl stearate, retinyl palmitate), vitamin E (alpha-tocopherol and gamma-tocopherol) and selected carotenoids. Family differences were found for 25(OH)D, retinol, retinyl stearate, retinyl palmitate and gamma-tocopherol. Species differences were found for all detectable measurements. Carotenoids were not detected in any species. The large number of animals contributing to these data, provides a substantial base for comparing the nutritional status of healthy animals and the differences among them. PMID:11137448

Crissey, S; Ange, K; Slifka, K; Bowen, P; Stacewicz-Sapuntzakis, M; Langman, C; Sadler, W; Ward, A

2001-01-01

133

Abundance of diurnal raptors on open space grasslands in an urbanized landscape  

USGS Publications Warehouse

We conducted point counts of diurnal raptors on Boulder, Colorado, grasslands for three winters and summers, and compared results to landscape features of the count areas. Four wintering species were scarce on plots that included significant amounts of urban habitat, with a critical landscape threshold at about 5-7% urbanization: Bald Eagle (Haliaeetus leucocephalus), Ferruginous Hawk (Buteo regalis), Rough-legged Hawk (B. lagopus), and Prairie Falcon (Falco mexicanus). Counts of the first three species also were positively correlated with proximity of the count plots to the nearest colony of black-tailed prairie dogs (Cynomys ludovicianus). Two breeding species, the Red-tailed Hawk (B. jamaicensis) and Swainson's Hawk (B. swainsoni), were more abundant on plots dominated by lowland hayfields and tallgrass prairies, as opposed to upland mixed and shortgrass prairies. They, along with the ubiquitous American Kestrel (Falco sparverius), were not sensitive to the amounts of urbanization (up to 30%) that occurred in the landscapes sampled. Results of this study suggest that urban open space grasslands can support sizable populations of most diurnal raptors, as long as prey populations persist, but that some species are highly sensitive to landscape urbanization.

Berry, M.E.; Bock, C.E.; Haire, S.L.

1998-01-01

134

Association of wintering raptors with Conservation Reserve Enhancement Program grasslands in Pennsylvania  

USGS Publications Warehouse

Conservation grasslands can provide valuable habitat resource for breeding songbirds, but their value for wintering raptors has received little attention. We hypothesized that increased availability of grassland habitat through the Conservation Reserve Enhancement Program (CREP) has resulted in an increase or redistribution in numbers of four species of raptors in Pennsylvania since 2001. We tested this by analyzing winter raptor counts from volunteer surveys, conducted from 2001 to 2008, for Red-tailed Hawks (Buteo jamaicensis), Rough-legged Hawks (Buteo lagopus), Northern Harriers (Circus cyaneus), and American Kestrels (Falco sparverius). During that period, numbers of wintering Northern Harriers increased by more than 20% per year. Log-linear Poisson regression models show that all four species increased in the region of Pennsylvania that had the most and longest-established conservation grasslands. At the county scale (N= 67), Bayesian spatial models showed that spatial and temporal population trends of all four species were positively correlated with the amount of conservation grassland. This relationship was particularly strong for Northern Harriers, with numbers predicted to increase by 35.7% per year for each additional 1% of farmland enrolled in CREP. Our results suggest that conservation grasslands are likely the primary cause of the increase in numbers of wintering Northern Harriers in Pennsylvania since 2001. ?? 2010 The Authors. Journal of Field Ornithology ?? 2010 Association of Field Ornithologists.

Wilson, A.; Brittingham, M.; Grove, G.

2010-01-01

135

Influence of dietary feathers on the fecal microbiota in captive Arctic fox: do dietary hair or feathers play a role in the evolution of carnivorous mammals?  

PubMed

Hair and feathers are composed of keratin and are indigestible, inalimental and unpalatable for carnivores. However, carnivores often ingest hair and feathers during feeding or when grooming. We hypothesized that ingestion of hair and feathers changes species diversity and relative abundance of bacteria in the gut of carnivores. To test this hypothesis, we added disinfected poultry down feathers to the normal diet of captive Arctic foxes (Alopex lagopus). We then used fluorescently labeled terminal restriction fragments (T-RFs) to examine changes in fecal bacterial diversity and abundance. The results showed that the number of bacterial species increased significantly after feather ingestion, but that total abundance was unchanged. This demonstrated that addition of disinfected feathers to the diet stimulated increased production among less abundant bacteria, resulting in a balancing of relative abundance of different bacterial species, or that some newly-ingested microbial species would colonize the gut because a suitable microhabitat had become available. This implies that the overall production of bacterial metabolites would be made up of a greater range of substances after feather ingestion. On one hand, the host's immune response would be more diverse, increasing the capacity of the immune system to regulate gut microflora. On the other hand, the animal's physiological performance would also be affected. For wild animals, such altered physiological traits would be subjected to natural selection, and, hence, persistent geographic differences in the character of ingested feathers or fur would drive speciation. PMID:25420637

Zhang, Liang; Yang, Shuhui; Xu, Yanchun; Dahmer, Thomas D

2014-11-01

136

Pyrenean ptarmigans decline under climatic and human influences through the Holocene  

PubMed Central

In Europe, the Quaternary is characterized by climatic fluctuations known to have led to many cycles of contraction and expansion of species geographical ranges. In addition, during the Holocene, historical changes in human occupation such as colonization or abandonment of traditional land uses can also affect habitats. These climatically or anthropically induced geographic range changes are expected to produce considerable effective population size change, measurable in terms of genetic diversity and organization. The rock ptarmigan (Lagopus muta) is a small-bodied grouse occurring throughout Northern hemispheric arctic and alpine tundra. This species is not considered threatened at a continental scale, but the populations in the Pyrenees are of concern because of their small population size, geographical isolation and low genetic diversity. Here, we used 11 microsatellites to investigate genetic variations and differentiations and infer the overall demographic history of Pyrenean rock ptarmigan populations. The low genetic variability found in these populations has been previously thought to be the result of a bottleneck that occurred following the last glacial maximum (i.e., 10?000 years ago) or more recently (i.e., during the last 200 years). Our results clearly indicate a major bottleneck affecting the populations in the last tenth of the Holocene. We discuss how this decline can be explained by a combination of unfavorable and successive events that increased the degree of habitat fragmentation. PMID:23838689

Bech, N; Barbu, C M; Quéméré, E; Novoa, C; Allienne, J F; Boissier, J

2013-01-01

137

Virological Investigation of Avian Influenza Virus on Postglacial Species of Phasianidae and Tetraonidae in the Italian Alps  

PubMed Central

Land-based birds, belonging to Galliformes order are considered to be potential intermediaries in the emergence of new strains of influenza A viruses (AIVs), but the viral circulation in these birds remains largely unknown. To gain insights into the circulation of AIV in the wild Galliformes populations in Italian Alps, we conducted a virological survey on rock partridge (Alectoris graeca saxatilis) belonging to Phasianidae family and on tetraonids including rock ptarmigan (Lagopus mutus helveticus) and black grouse (Tetrao tetrix tetrix). In 2003 and 2004, during the hunting seasons, 79 wild Galliformes, categorised into age and sex classes, were hunted in the Sondrio Province (Central Alps). Cloacal swabs were collected from 11 rock partridges and from 68 tetraonids including 23 alpine rock ptarmigans and 45 black grouses. We tested cloacal swabs by a high sensitive reverse transcription- (RT-) PCR detecting the matrix gene of AIV. No AIV was detected in the investigated samples, thus, suggesting the lack of AIV circulation in these relict populations in the study period. In terms of threatened species conservation, during wildlife management activities, it is very important to exclude the introduction of AIV-carrier birds in shared territories, a fact representing a health risk for these populations. PMID:24167732

Delogu, Mauro; Ghetti, Giulia; Gugiatti, Alessandro; Cotti, Claudia; Piredda, Isabella; Frasnelli, Matteo; De Marco, Maria A.

2013-01-01

138

Two missense mutations in melanocortin 1 receptor (MC1R) are strongly associated with dark ventral coat color in reindeer (Rangifer tarandus).  

PubMed

The protein-coding region of melanocortin 1 receptor (MC1R) was sequenced to identify potential variation affecting coat color in reindeer (Rangifer tarandus). A T?C sequence variation at nucleotide position 218 (c.218T>C) causing an amino acid (aa) change from methionine to threonine at aa position 73 (p.Met73Thr) was identified. In addition, a T?G sequence variation was found at nucleotide position 839 (c.839T>G), causing phenylalanine to be exchanged by cysteine at aa position 280 (p.Phe280Cys). The two sequence variants (c.218C and c.839G) were found to be closely associated with a darker belly coat compared with animals not having any of these two variants. The aa acid change p.Met73Thr affects the same position as p.Met73Lys previously reported to give constitutive activation of MC1R in black sheep (Ovis aries), whereas p.Phe280Cys is identical to one of two variants previously reported to be associated with dark coat color in Arctic fox (Alopex lagopus), supporting that the two variants found in reindeer are functional. The complete absence of Thr73 and Cys280 among the 51 wild reindeer analyzed provides some evidence that these variants are more common in the domestic herds. PMID:25039753

Våge, D I; Nieminen, M; Anderson, D G; Røed, K H

2014-10-01

139

Mother knows best: functionally referential alarm calling in white-tailed ptarmigan.  

PubMed

Functionally referential alarm calls have stimulus specificity, distinct acoustic structure, and elicit different escape responses that are appropriate to the threat. The mechanisms by which escape responses are evoked are not fully understood and may range from eliciting innate responses to conveying representational information. White-tailed ptarmigan (Lagopus leucurus) are a long-lived alpine tundra grouse, which are preyed upon by aerial and terrestrial predators. We investigated the hypothesis that alarm calls of ptarmigan hens with chicks are functionally referential. We recorded hens' alarm calls in response to naturally occurring and model predators in California's Sierra Nevada alpine tundra for two summer seasons. We conducted playback experiments in the field to determine chick responses to alarm calls. Alarm calls commenced with an extended 'alerting' note followed by a series of staccato notes grouped into elements. Fundamental and dominant frequencies in element notes were significantly higher in terrestrial compared to aerial threat alarm calls. Playbacks of terrestrial threat alarm calls elicited an upright/alert position by chicks (75 % of responses). In response to aerial threat alarm call playbacks, chicks flattened to the ground and froze (80 % of responses). To our knowledge, this study provides the first empirical evidence of functionally referential alarm calling, including the responses of the receivers, in an avian species in the wild. PMID:24132414

Ausmus, Desa M; Clarke, Jennifer A

2014-05-01

140

Pyrenean ptarmigans decline under climatic and human influences through the Holocene.  

PubMed

In Europe, the Quaternary is characterized by climatic fluctuations known to have led to many cycles of contraction and expansion of species geographical ranges. In addition, during the Holocene, historical changes in human occupation such as colonization or abandonment of traditional land uses can also affect habitats. These climatically or anthropically induced geographic range changes are expected to produce considerable effective population size change, measurable in terms of genetic diversity and organization. The rock ptarmigan (Lagopus muta) is a small-bodied grouse occurring throughout Northern hemispheric arctic and alpine tundra. This species is not considered threatened at a continental scale, but the populations in the Pyrenees are of concern because of their small population size, geographical isolation and low genetic diversity. Here, we used 11 microsatellites to investigate genetic variations and differentiations and infer the overall demographic history of Pyrenean rock ptarmigan populations. The low genetic variability found in these populations has been previously thought to be the result of a bottleneck that occurred following the last glacial maximum (i.e., 10,000 years ago) or more recently (i.e., during the last 200 years). Our results clearly indicate a major bottleneck affecting the populations in the last tenth of the Holocene. We discuss how this decline can be explained by a combination of unfavorable and successive events that increased the degree of habitat fragmentation. PMID:23838689

Bech, N; Barbu, C M; Quéméré, E; Novoa, C; Allienne, J F; Boissier, J

2013-11-01

141

Virological investigation of avian influenza virus on postglacial species of phasianidae and tetraonidae in the italian alps.  

PubMed

Land-based birds, belonging to Galliformes order are considered to be potential intermediaries in the emergence of new strains of influenza A viruses (AIVs), but the viral circulation in these birds remains largely unknown. To gain insights into the circulation of AIV in the wild Galliformes populations in Italian Alps, we conducted a virological survey on rock partridge (Alectoris graeca saxatilis) belonging to Phasianidae family and on tetraonids including rock ptarmigan (Lagopus mutus helveticus) and black grouse (Tetrao tetrix tetrix). In 2003 and 2004, during the hunting seasons, 79 wild Galliformes, categorised into age and sex classes, were hunted in the Sondrio Province (Central Alps). Cloacal swabs were collected from 11 rock partridges and from 68 tetraonids including 23 alpine rock ptarmigans and 45 black grouses. We tested cloacal swabs by a high sensitive reverse transcription- (RT-) PCR detecting the matrix gene of AIV. No AIV was detected in the investigated samples, thus, suggesting the lack of AIV circulation in these relict populations in the study period. In terms of threatened species conservation, during wildlife management activities, it is very important to exclude the introduction of AIV-carrier birds in shared territories, a fact representing a health risk for these populations. PMID:24167732

Delogu, Mauro; Ghetti, Giulia; Gugiatti, Alessandro; Cotti, Claudia; Piredda, Isabella; Frasnelli, Matteo; De Marco, Maria A

2013-01-01

142

Persistent organochlorine levels in six prey species of the gyrfalcon Falco rusticolus in Iceland.  

PubMed

Our previous investigations have revealed very high levels of organochlorines (OCs) in the Icelandic gyrfalcon Falco rusticolus, a resident top predator. We now examine six potential prey species of birds, both resident and migratory, in order to elucidate the most likely route of the OCs to the gyrfalcon. The ptarmigan Lagopus mutus, the most important prey of the gyrfalcon, contained very low levels of OCs. Bioaccumulation of polychlorinated biphenyls (PCBs) and DDTs in mallards Anas platyrhynchos, tufted ducks Aythya fuligula, golden plovers Pluvialis apricaria, purple sandpipers Calidris maritima, and black guillemots Cepphus grylle reflected their position in the foodchain. The differences in OC-levels seem nevertheless too high just to reflect the different food-chain levels of these species in Iceland. The winter grounds of the migratory golden plovers and tufted ducks appear to be more contaminated than the Icelandic terrestrial habitat of ptarmigans or the freshwater habitat as reflected in mallards, both resident species. However, spending the winter on the coast in Iceland, results in high levels of contaminants in purple sandpipers and black guillemots. Our results indicate OC contamination of the marine ecosystem in Iceland while the terrestrial and freshwater ecosystems are little affected. It is postulated that gyrfalcons receive the major part of the observed contamination from prey other than ptarmigan, especially birds associated with the marine ecosystem and also from migratory birds. PMID:11234542

Olafsdóttir, K; Petersen, A E; Magnúsdóttir, E V; Björnsson, T; Jóhannesson, T

2001-01-01

143

Unexpected diversity of the cestode Echinococcus multilocularis in wildlife in Canada.  

PubMed

Echinococcus multilocularis is a zoonotic cestode with a distribution encompassing the northern hemisphere that causes alveolar hydatid disease in people and other aberrant hosts. E. multilocularis is not genetically uniform across its distribution, which may have implications for zoonotic transmission and pathogenicity. Recent findings of a European-type haplotype of E. multilocularis in wildlife in one location in western Canada motivated a broader survey of the diversity of this parasite in wildlife from northern and western Canada. We obtained intact adult cestodes of E. multilocularis from the intestines of 41 wild canids (wolf - Canis lupus, coyote - Canis latrans, and red fox - Vulpes vulpes), taeniid eggs from 28 fecal samples from Arctic fox (Vulpes lagopus), and alveolar hydatid cysts from 39 potential rodent intermediate hosts. Upon sequencing a 370-nucelotide region of the NADH dehydrogenase subunit 1 (nad1) mitochondrial locus, 17 new haplotypes were identified. This constitutes a much higher diversity than expected, as only two genotypes (European and an Asian/North American) had previously been identified using this locus. The European-type strain, recently introduced, may be widespread in wildlife within western Canada, possibly related to the large home ranges and wide dispersal range of wild canids. This study increased understanding of the biogeographic distribution, prevalence and genetic differences of a globally important pathogenic cestode in northern and western Canada. PMID:25161905

Gesy, Karen M; Schurer, Janna M; Massolo, Alessandro; Liccioli, Stefano; Elkin, Brett T; Alisauskas, Ray; Jenkins, Emily J

2014-08-01

144

Unexpected diversity of the cestode Echinococcus multilocularis in wildlife in Canada  

PubMed Central

Echinococcus multilocularis is a zoonotic cestode with a distribution encompassing the northern hemisphere that causes alveolar hydatid disease in people and other aberrant hosts. E.multilocularis is not genetically uniform across its distribution, which may have implications for zoonotic transmission and pathogenicity. Recent findings of a European-type haplotype of E. multilocularis in wildlife in one location in western Canada motivated a broader survey of the diversity of this parasite in wildlife from northern and western Canada. We obtained intact adult cestodes of E. multilocularis from the intestines of 41 wild canids (wolf – Canis lupus, coyote – Canis latrans, and red fox – Vulpes vulpes), taeniid eggs from 28 fecal samples from Arctic fox (Vulpes lagopus), and alveolar hydatid cysts from 39 potential rodent intermediate hosts. Upon sequencing a 370-nucelotide region of the NADH dehydrogenase subunit 1 (nad1) mitochondrial locus, 17 new haplotypes were identified. This constitutes a much higher diversity than expected, as only two genotypes (European and an Asian/North American) had previously been identified using this locus. The European-type strain, recently introduced, may be widespread in wildlife within western Canada, possibly related to the large home ranges and wide dispersal range of wild canids. This study increased understanding of the biogeographic distribution, prevalence and genetic differences of a globally important pathogenic cestode in northern and western Canada. PMID:25161905

Gesy, Karen M.; Schurer, Janna M.; Massolo, Alessandro; Liccioli, Stefano; Elkin, Brett T.; Alisauskas, Ray; Jenkins, Emily J.

2014-01-01

145

Persistence of antibodies in blood and body fluids in decaying fox carcasses, as exemplified by antibodies against Microsporum canis  

PubMed Central

To assist in evaluating serological test results from dead animals, 10 silver foxes (Vulpes vulpes) and 10 blue foxes (Alopex lagopus), 6 of each species previously vaccinated against and all challenged with Microsporum canis, were blood sampled and euthanased. Fox carcasses were stored at +10°C, and autopsy was performed on Days 0, 2, 4, 7, and 11 post mortem during which samples from blood and/or body fluid from the thoracic cavity were collected. Antibodies against M. canis were measured in an enzyme-linked immunosorbent assay (ELISA) as absorbance values (optical density; OD). To assess the degradation of antibodies, the ratio between post mortem and ante mortem absorbance was calculated. The mean absorbance from samples collected during autopsy was generally lower than from samples from live animals. In blood samples, this difference increased significantly with time (P = 0.04), while in body fluid samples the difference decreased (not significant; P = 0.18). We suggest that a positive serological result from testing blood or body fluid of a dead animal may be regarded as valuable, although specific prevalences obtained by screening populations based on this type of material may represent an under-estimation of the true antibody prevalence. Negative serological test results based on material from carcasses may be less conclusive, taken into account the general degradation processes in decaying carcasses, also involving immunoglobulin proteins. PMID:16987389

Tryland, Morten; Handeland, Kjell; Bratberg, Anna-Marie; Solbakk, Inge-Tom; Oksanen, Antti

2006-01-01

146

Mechanism of Gene Amplification via Yeast Autonomously Replicating Sequences  

PubMed Central

The present investigation was aimed at understanding the molecular mechanism of gene amplification. Interplay of fragile sites in promoting gene amplification was also elucidated. The amplification promoting sequences were chosen from the Saccharomyces cerevisiae ARS, 5S rRNA regions of Plantago ovata and P. lagopus, proposed sites of replication pausing at Ste20 gene locus of S. cerevisiae, and the bend DNA sequences within fragile site FRA11A in humans. The gene amplification assays showed that plasmid bearing APS from yeast and human beings led to enhanced protein concentration as compared to the wild type. Both the in silico and in vitro analyses were pointed out at the strong bending potential of these APS. In addition, high mitotic stability and presence of TTTT repeats and SAR amongst these sequences encourage gene amplification. Phylogenetic analysis of S. cerevisiae ARS was also conducted. The combinatorial power of different aspects of APS analyzed in the present investigation was harnessed to reach a consensus about the factors which stimulate gene expression, in presence of these sequences. It was concluded that the mechanism of gene amplification was that AT rich tracts present in fragile sites of yeast serve as binding sites for MAR/SAR and DNA unwinding elements. The DNA protein interactions necessary for ORC activation are facilitated by DNA bending. These specific bindings at ORC promote repeated rounds of DNA replication leading to gene amplification.

Dhar, M. K.

2015-01-01

147

Trophic interactions in a high arctic snow goose colony.  

PubMed

We examined the role of trophic interactions in structuring a high arctic tundra community characterized by a large breeding colony of greater snow geese (Chen caerulescens atlantica). According to the exploitation ecosystem hypothesis of Oksanen et al. (1981), food chains are controlled by top-down interactions. However, because the arctic primary productivity is low, herbivore populations are too small to support functional predator populations and these communities should thus be dominated by the plant/ herbivore trophic-level interaction. Since 1990, we have been monitoring annual abundance and productivity of geese, the impact of goose grazing, predator abundance (mostly arctic foxes, Alopex lagopus) and the abundance of lemmings, the other significant herbivore in this community, on Bylot Island, Nunavut, Canada. Goose grazing consistently removed a significant proportion of the standing crop (?40%) in tundra wetlands every year. Grazing changed plant community composition and reduced the production of grasses and sedges to a low-level equilibrium compared to the situation where the presence of geese had been removed. Lemming cyclic fluctuations were strong and affected fox reproduction. Fox predation on goose eggs was severe and generated marked annual variation in goose productivity. Predation intensity on geese was closely related to the lemming cycle, a consequence of an indirect interaction between lemming and geese via shared predators. We conclude that, contrary to the exploitation ecosystem hypothesis, both the plant/herbivore and predator/prey interactions are significant in this arctic community. PMID:21680492

Gauthier, Gilles; Bêty, Joël; Giroux, Jean-François; Rochefort, Line

2004-04-01

148

Serological and parasitological prevalence of Toxoplasma gondii in wild birds from Colorado.  

PubMed

Ground-feeding birds are considered important in the epidemiology of Toxoplasma gondii because they serve as indicators of soil contamination by oocysts, and birds of prey are indicators of T. gondii prevalence in rodents and other small mammals. Cats excrete environmentally resistant oocysts after consuming tissues of T. gondii -infected birds. In the present study, sera and tissues from 382 wild birds from Colorado were tested for T. gondii infection. Antibodies to T. gondii were found in 38 birds with the use of the modified agglutination test (MAT, 1?25 titer). Tissues (brains, hearts) of 84 birds were bioassayed in mice. Viable T. gondii was isolated from 1 of 1 barn owl (Tyto alba), 1 of 5 American kestrels (Falco sparverius), 1 of 7 ferruginous hawks (Buteo regalis), 1 of 4 rough-legged hawks (Buteo lagopus), 2 of 13 Swainson's hawks (Buteo swainsoni), and 1 of 25 red-tailed hawks (Buteo jamaicensis). This is the first time T. gondii has been isolated from the barn owl, ferruginous hawk, rough-legged hawk, and Swainson's hawk. PMID:20950101

Dubey, J P; Felix, T A; Kwok, O C H

2010-10-01

149

Winter habitat associations of diurnal raptors in Californias Central Valley  

USGS Publications Warehouse

The wintering raptors of California's Central Valley are abundant and diverse. Despite this, little information exists on the habitats used by these birds in winter. We recorded diurnal raptors along 19 roadside survey routes throughout the Central Valley for three consecutive winters between 2007 and 2010. We obtained data sufficient to determine significant positive and negative habitat associations for the White-tailed Kite (Elanus leucurus), Bald Eagle {Haliaeetus leucocephalus), Northern Harrier (Circus cyaneus), Red-tailed Hawk (Buteo jamaicensis), Ferruginous Hawk (Buteo regalis), Rough-legged Hawk (Buteo lagopus), American Kestrel (Falco sparverius), and Prairie Falcon (Falco mexicanus). The Prairie Falcon and Ferruginous and Rough-legged hawks showed expected strong positive associations with grasslands. The Bald Eagle and Northern Harrier were positively associated not only with wetlands but also with rice. The strongest positive association for the White-tailed Kite was with wetlands. The Red-tailed Hawk was positively associated with a variety of habitat types but most strongly with wetlands and rice. The American Kestrel, Northern Harrier, and White-tailed Kite were positively associated with alfalfa. Nearly all species were negatively associated with urbanized landscapes, orchards, and other intensive forms of agriculture. The White-tailed Kite, Northern Harrier, Redtailed Hawk, Ferruginous Hawk, and American Kestrel showed significant negative associations with oak savanna. Given the rapid conversion of the Central Valley to urban and intensive agricultural uses over the past few decades, these results have important implications for conservation of these wintering raptors in this region.

Pandolrno, E.R.; Herzog, M.P.; Hooper, S.L.; Smith, Z.

2011-01-01

150

Late Quaternary mammalian zoogeography of eastern Washington  

NASA Astrophysics Data System (ADS)

The late Quaternary mammalian zoogeographic history of eastern Washington as revealed by archaeological and paleontological research conforms to a set of past environmental conditions inferred from botanical data. During the relatively cool and moist late Pleistocene and early Holocene, Cervus cf. elaphus, Ovis canadensis, Vulpes vulpes, Martes americana, Alopex lagopus, and perhaps Rangifer sp., taxa with ecological preferences for mesic steppe habitats, were present in the now xeric Columbia Basin. As the climate became progressively warmer and drier during the late Pleistocene and early Holocene, Antilocapra americana, Onychomys leucogaster, Spermophilus townsendii, and Neotoma cinerea, taxa with ecological preferences for xeric steppe habitats, appear in the Columbia Basin. Bison sp. and Taxidea taxus may have been present in eastern Washington for the last 20,000 yr. Middle and late Holocene records for Oreamnos americanus, Spermophilus columbianus, S. townsendii, Lagurus curtatus, and Urocyon cinereoargenteus in central eastern Washington suggest fluctuations in the ranges of these taxa that conform to a middle Holocene period of less effective precipitation and a ca. 3500-yr-old period of more effective precipitation before essentially modern environmental conditions prevailed.

Lyman, R. Lee; Livingston, Stephanie D.

1983-11-01

151

The influence of fine-scale habitat features on regional variation in population performance of alpine White-tailed Ptarmigan  

USGS Publications Warehouse

It is often assumed (explicitly or implicitly) that animals select habitat features to maximize fitness. However, there is often a mismatch between preferred habitats and indices of individual and population measures of performance. We examined the influence of fine-scale habitat selection on the overall population performance of the White-tailed Ptarmigan (Lagopus leucura), an alpine specialist, in two subdivided populations whose habitat patches are configured differently. The central region of Vancouver Island, Canada, has more continuous and larger habitat patches than the southern region. In 2003 and 2004, using paired logistic regression between used (n = 176) and available (n = 324) sites, we identified food availability, distance to standing water, and predator cover as preferred habitat components . We then quantified variation in population performance in the two regions in terms of sex ratio, age structure (n = 182 adults and yearlings), and reproductive success (n = 98 females) on the basis of 8 years of data (1995-1999, 2002-2004). Region strongly influenced females' breeding success, which, unsuccessful hens included, was consistently higher in the central region (n = 77 females) of the island than in the south (n = 21 females, P = 0.01). The central region also had a much higher proportion of successful hens (87%) than did the south (55%, P < 0.001). In light of our findings, we suggest that population performance is influenced by a combination of fine-scale habitat features and coarse-scale habitat configuration. ?? The Cooper Ornithological Society 2011.

Fedy, B.; Martin, K.

2011-01-01

152

Enhancement of local species richness in tundra by seed dispersal through guts of muskox and barnacle goose.  

PubMed

The potential contribution of vertebrate-mediated seed rain to the maintenance of plant community richness in a High Arctic ecosystem was investigated. We analyzed viable seed content in dung of the four numerically most important terrestrial vertebrates in Northeast Greenland - muskox (Ovibos moschatus), barnacle goose (Branta leucopsis), Arctic fox (Alopex lagopus) and Arctic hare (Lepus arcticus). High numbers of plant propagules were found in the dung of muskox and barnacle goose. Seeds of many plant species were found in the faeces of one vertebrate species only. Propagule composition in barnacle goose droppings was relatively uniform over samples, with a high abundance of the nutritious bulbils of Polygonum viviparum (Bistorta vivipara), suggesting that geese have a narrow habitat preference and feed selectively. Propagule composition in muskox dung was diverse and heterogeneous among samples, suggesting a generalist approach in terms of food selection and the haphazard ingestion of plant propagules with foliage. The species composition of plant propagules in dung samples was different from that of the receiving plant communities (in terms of the Sørensen and Czekanowski dissimilarity indices), and dung deposition, especially by muskox, often brought new species to the receiving community. The results suggest that endozoochorous propagule dispersal in the Arctic has a great potential in the generation and maintenance of local species richness, albeit being little specialized. It is further suggested that endozoochory is an important means of long-distance dispersal and, thereby, of plant migration in response to climate change. PMID:17990003

Bruun, Hans Henrik; Lundgren, Rebekka; Philipp, Marianne

2008-02-01

153

Oral Rabies Vaccination in North America: Opportunities, Complexities, and Challenges  

PubMed Central

Steps to facilitate inter-jurisdictional collaboration nationally and continentally have been critical for implementing and conducting coordinated wildlife rabies management programs that rely heavily on oral rabies vaccination (ORV). Formation of a national rabies management team has been pivotal for coordinated ORV programs in the United States of America. The signing of the North American Rabies Management Plan extended a collaborative framework for coordination of surveillance, control, and research in border areas among Canada, Mexico, and the US. Advances in enhanced surveillance have facilitated sampling of greater scope and intensity near ORV zones for improved rabies management decision-making in real time. The value of enhanced surveillance as a complement to public health surveillance was best illustrated in Ohio during 2007, where 19 rabies cases were detected that were critical for the formulation of focused contingency actions for controlling rabies in this strategically key area. Diverse complexities and challenges are commonplace when applying ORV to control rabies in wild meso-carnivores. Nevertheless, intervention has resulted in notable successes, including the elimination of an arctic fox (Vulpes lagopus) rabies virus variant in most of southern Ontario, Canada, with ancillary benefits of elimination extending into Quebec and the northeastern US. Progress continues with ORV toward preventing the spread and working toward elimination of a unique variant of gray fox (Urocyon cinereoargenteus) rabies in west central Texas. Elimination of rabies in coyotes (Canis latrans) through ORV contributed to the US being declared free of canine rabies in 2007. Raccoon (Procyon lotor) rabies control continues to present the greatest challenges among meso-carnivore rabies reservoirs, yet to date intervention has prevented this variant from gaining a broad geographic foothold beyond ORV zones designed to prevent its spread from the eastern US. Progress continues toward the development and testing of new bait-vaccine combinations that increase the chance for improved delivery and performance in the diverse meso-carnivore rabies reservoir complex in the US. PMID:20027214

Slate, Dennis; Algeo, Timothy P.; Nelson, Kathleen M.; Chipman, Richard B.; Donovan, Dennis; Blanton, Jesse D.; Niezgoda, Michael; Rupprecht, Charles E.

2009-01-01

154

Sarcocystis caninum and Sarcocystis svanai n. spp. (Apicomplexa: Sarcocystidae) Associated with Severe Myositis and Hepatitis in the Domestic Dog (Canis familiaris).  

PubMed

There are several reports of Sarcocystis sarcocysts in muscles of dogs, but these species have not been named. Additionally, there are two reports of Sarcocystis neurona in dogs. Here, we propose two new names, Sarcocystis caninum, and Sarcocystis svanai for sarcocysts associated with clinical muscular sarcocystosis in four domestic dogs (Canis familiaris), one each from Montana and Colorado in the USA, and two from British Columbia, Canada. Only the sarcocyst stage was identified. Most of the sarcocysts identified were S. caninum. Sarcocysts were studied using light microscopy, transmission electron microscopy (TEM), and polymerase chain reaction. Based on collective results two new species, S. caninum and S. svanai were designated. Sarcocystis caninum and S. svanai were structurally distinct. Sarcocystis caninum sarcocysts were up to 1.2 mm long and up to 75 ?m wide. By light microscopy, the sarcocyst wall was relatively thin and smooth. By TEM, the sarcocyst wall was "type 9", 1-2 ?m thick, and contained villar protrusions that lacked microtubules. Bradyzoites in sections were 7-9 ?m long. Sarcocysts of S. svanai were few and were identified by TEM. Sarcocystis svanai sarcocysts were "type 1", thin walled (< 0.5 ?m), and the wall lacked villar protrusions but had tiny blebs that did not invaginate. DNA was extracted either from infected frozen muscle biopsies or formalin-fixed paraffin-embedded sections. Dogs were either singly infected with S. caninum or multiply co-infected with S. caninum and S. svanai (the result of a mixed infection) based on multilocus DNA sequencing and morphology. BLASTn analysis established that the sarcocysts identified in these dogs were similar to, but not identical to Sarcocystis canis or Sarcocystis arctosi, parasites found to infect polar bears (Ursus maritimus) or brown bears (Ursus arctosi), respectively. However, the S. caninum sequence showed 100% identify over the 18S rRNA region sequenced to that of S. arctica, a parasite known to infect Arctic foxes (Vulpes lagopus). PMID:25256157

Dubey, Jitender P; Sykes, Jane E; Shelton, G Diane; Sharp, Nick; Verma, Shiv K; Calero-Bernal, Rafael; Viviano, Jenifer; Sundar, Natarajan; Khan, Asis; Grigg, Michael E

2014-09-24

155

Predation pressure by avian predators suggests summer limitation of small-mammal populations in the Canadian Arctic.  

PubMed

Predation has been suggested to be especially important in simple food webs and less productive ecosystems such as the arctic tundra, but very few data are available to evaluate this hypothesis. We examined the hypothesis that avian predators could drive the population dynamics of two cyclic lemming species in the Canadian Arctic. A dense and diverse suite of predatory birds, including the Snowy Owl (Bubo scandiacus), the Rough-legged Hawk (Buteo lagopus), and the Long-tailed Jaeger (Stercorarius longicaudus), inhabits the arctic tundra and prey on collared (Dicrostonyx groenlandicus) and brown (Lemmus trimucronatus) lemmings during the snow-free period. We evaluated the predation pressure exerted by these predators by combining their numerical (variation in breeding and fledgling numbers) and functional (variation in diet and daily consumption rates) responses to variations in lemming densities over the 2004-2010 period. Breeding density and number of fledglings produced by the three main avian predators increased sharply without delay in response to increasing lemming densities. The proportion of collared lemmings in the diet of those predators was high at low lemming density (both species) but decreased as lemming density increased. However, we found little evidence that their daily consumption rates vary in relation to changes in lemming density. Total consumption rate by avian predators initially increased more rapidly for collared lemming but eventually leveled off at a much higher value for brown lemmings, the most abundant species at our site. The combined daily predation rate of avian predators exceeded the maximum daily potential growth rates of both lemming species except at the highest recorded densities for brown lemmings. We thus show, for the first time, that predation pressure exerted without delay by avian predators can limit populations of coexisting lemming species during the snow-free period, and thus, that predation could play a role in the cyclic dynamic of these species in the tundra. PMID:24649646

Therrien, J F; Gauthier, G; Korpimäki, E; Bêty, J

2014-01-01

156

Genetic characterisation of Toxoplasma gondii in wildlife from North America revealed widespread and high prevalence of the fourth clonal type  

USGS Publications Warehouse

Little is known of the genetic diversity of Toxoplasma gondii circulating in wildlife. In the present study wild animals, from the USA were examined for T. gondii infection. Tissues of naturally exposed animals were bioassayed in mice for isolation of viable parasites. Viable T. gondii was isolated from 31 animals including, to our knowledge for the first time, from a bald eagle (Haliaeetus leucocephalus), five gray wolves (Canis lupus), a woodrat (Neotoma micropus), and five Arctic foxes (Alopex lagopus). Additionally, 66 T. gondii isolates obtained previously, but not genetically characterised, were revived in mice. Toxoplasma gondii DNA isolated from these 97 samples (31+66) was characterised using 11 PCR-restriction fragment length polymorphism (RFLP) markers (SAG1, 5'- and 3'-SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico). A total of 95 isolates were successfully genotyped. In addition to clonal Types II, and III, 12 different genotypes were found. These genotype data were combined with 74 T. gondii isolates previously characterised from wildlife from North America and a composite data set of 169 isolates comprised 22 genotypes, including clonal Types II, III and 20 atypical genotypes. Phylogenetic network analysis showed limited diversity with dominance of a recently designated fourth clonal type (Type 12) in North America, followed by the Type II and III lineages. These three major lineages together accounted for 85% of strains in North America. The Type 12 lineage includes previously identified Type A and X strains from sea otters. This study revealed that the Type 12 lineage accounts for 46.7% (79/169) of isolates and is dominant in wildlife of North America. No clonal Type I strain was identified among these wildlife isolates. These results suggest that T. gondii strains in wildlife from North America have limited diversity, with the occurrence of only a few major clonal types.

Dubey, J.P.; Velmurugan, G.V.; Ragendran, C.; Yabsley, M.J.; Thomas, N.J.; Beckmen, K.B.; Sinnett, D.; Ruid, D.; Hart, J.; Fair, P.A.; McFee, W.E.; Shearn-Bochsler, V.; Kwok, O.C.H.; Ferreira, L.R.; Choudhary, S.; Faria, E.B.; Zhou, H.; Felix, T.A.; Su, C.

2011-01-01

157

Falcon versus grouse: flight adaptations of a predator and its prey  

USGS Publications Warehouse

Several falcons were trained to fly along a 500 m course to a lure. The air speeds of the more consistent performers averaged about 1.5 times their calculated minimum power speeds, and occasionally reached 2.1 times the minimum power speed. Wing beat frequencies of all the falcons were above those estimated from earlier field observations, and the same was true of wild Sage Grouse Centrocercus urophasianus, a regular falconer's quarry in the study area. Measurements of grouse killed by falcons showed that their wings were short, with broad slotted tips, whereas the falcons' wings were longer in relation to their body mass, and tapered. The short wings of grouse result in fast flight, high power requirements, and reduced capacity for aerobic flight. Calculations indicated that the grouse should fly faster than the falcons, and had the large amount of flight muscle needed to do so, but that the falcons would be capable of prolonged aerobic flight, whereas the grouse probably would not. We surmise that Sage Grouse cannot fly continuously without incurring an oxygen debt, and are therefore not long-distance migrants, although this limitation is partly due to their large size, and would not apply to smaller galliform birds such as ptarmigan Lagopus spp. The wing action seen in video recordings of the falcons was not consistent with the maintenance of constant circulation. We call it 'chase mode' because it appears to be associated with a high level of muscular exertion, without special regard to fuel economy. It shows features in common with the 'bounding' flight of passerines.

Pennycuick, C.J.; Fuller, M.R.; Oar, J.J.; Kirkpatrick, S.J.

1994-01-01

158

Impact of transient climate change upon Grouse population dynamics in the Italian Alps  

NASA Astrophysics Data System (ADS)

Understanding the effect of short to medium term weather condition, and of transient global warming upon wildlife species life history is essential to predict the demographic consequences therein, and possibly develop adaptation strategies, especially in game species, where hunting mortality may play an important role in population dynamics. We carried out a preliminary investigation of observed impact of weather variables upon population dynamics indexes of three alpine Grouse species (i.e. Rock Ptarmigan, Lagopus Mutus, Black Grouse, Tetrao Tetrix, Rock Partridge, Alectoris Graeca), nested within central Italian Alps, based upon 15 years (1995-2009) of available censuses data, provided by the Sondrio Province authority. We used a set of climate variables already highlighted within recent literature for carrying considerable bearing on Grouse population dynamics, including e.g. temperature at hatching time and during winter, snow cover at nesting, and precipitation during nursing period. We then developed models of Grouses' population dynamics by explicitly driving population change according to their dependence upon the significant weather variables and population density and we evaluated objective indexes to assess the so obtained predictive power. Eventually, we develop projection of future local climate, based upon locally derived trends, and upon projections from GCMs (A2 IPCC storyline) already validated for the area, to project forward in time (until 2100 or so) the significant climatic variables, which we then use to force population dynamics models of the target species. The projected patterns obtained through this exercise are discussed and compared against those expected under stationary climate conditions at present, and preliminary conclusions are drawn.

Pirovano, Andrea; Bocchiola, Daniele

2010-05-01

159

Alpine plant community trends on the elk summer range of Rocky Mountain National Park, Colorado: an analysis of existing data  

USGS Publications Warehouse

The majority of the elk (Cervus elaphus) population of Rocky Mountain National Park in Colorado summer in the parka??s high elevation alpine and subalpine meadows and willow krummholz. The parka??s population of white-tailed ptarmigan (Lagopus leucurus altipetens) depends on both dwarf and krummholz willows for food and cover. Concern about the effects of elk herbivory on these communities prompted the monitoring of 12 vegetation transects in these regions from 1971 to 1996. Over this 25-year period, data were collected on plant species cover and frequency and shrub heights. These data have not been statistically analyzed for trends in measured variable over time to determine changes in species abundance. Krummholz willow species (Salix planifolia, S. brachycarpa) declined 17-20 percent in cover and about 25 centimeters in height over the study period. Graminoids (particularly Deschampsia caespitosa, Carex, and Poa) increased slightly from 1971 to 1996. No significant increases of nonnative plant species were observed. An increase in presence of bare ground over the 25-year period warrants continued measurement of these transects. Lack of good data on elk density, distribution, or sue levels precluded correlating changes in plant species cover, frequency, or heights with elk population trends. I recommend development of a more rigorously designed monitoring program that includes these transects as well as other chosen on a random or stratified design and consistent measurement protocol and sampling intervals. Some method of quantifying elk use, either through measurement of plant utilization, pellet counts, or census-type surveys, would allow correlation of changes in plant species over time with changes in elk distribution and density on the parka??s alpine and subalpine regions.

Zeigenfuss, Linda C.

2006-01-01

160

Trophic relationships in an Arctic food web and implications for trace metal transfer.  

PubMed

Tissues of subsistence-harvested Arctic mammals were analyzed for silver (Ag), cadmium (Cd), and total mercury (THg). Muscle (or total body homogenates of potential fish and invertebrate prey) was analyzed for stable carbon (delta13C) and nitrogen (delta15N) isotopes to establish trophic interactions within the Arctic food chain. Food web magnification factors (FWMFs) and biomagnification factors for selected predator-prey scenarios (BMFs) were calculated to describe pathways of heavy metals in the Alaskan Arctic. FWMFs in this study indicate that magnification of selected heavy metals in the Arctic food web is not significant. Biomagnification of Cd occurs mainly in kidneys; calculated BMFs are higher for hepatic THg than renal THg for all predator-prey scenarios with the exception of polar bears (Ursus maritimus). In bears, the accumulation of renal THg is approximately 6 times higher than in liver. Magnification of hepatic Ag is minimal for all selected predator-prey scenarios. Though polar bears occupy a higher trophic level than belugas (Delphinapterus leucas), based on delta15N, the metal concentrations are either not statistically different between the two species or lower for bears. Similarly, concentrations of renal and hepatic Cd are significantly lower or not statistically different in polar bears compared to ringed (Phoca hispida) and bearded seals (Erignathus barbatus), their primary prey. THg, on the other hand, increased significantly from seal to polar bear tissues. Mean delta15N was lowest in muscle of Arctic fox (Alopex lagopus) and foxes also show the lowest levels of Hg, Cd and Ag in liver and kidney compared to the other species analyzed. These values are in good agreement with a diet dominated by terrestrial prey. Metal deposition in animal tissues is strongly dependent on biological factors such as diet, age, sex, body condition and health, and caution should be taken when interpreting magnification of dynamic and actively regulated trace metals. PMID:16387350

Dehn, Larissa-A; Follmann, Erich H; Thomas, Dana L; Sheffield, Gay G; Rosa, Cheryl; Duffy, Lawrence K; O'Hara, Todd M

2006-06-01

161

Oral rabies vaccination in north america: opportunities, complexities, and challenges.  

PubMed

Steps to facilitate inter-jurisdictional collaboration nationally and continentally have been critical for implementing and conducting coordinated wildlife rabies management programs that rely heavily on oral rabies vaccination (ORV). Formation of a national rabies management team has been pivotal for coordinated ORV programs in the United States of America. The signing of the North American Rabies Management Plan extended a collaborative framework for coordination of surveillance, control, and research in border areas among Canada, Mexico, and the US. Advances in enhanced surveillance have facilitated sampling of greater scope and intensity near ORV zones for improved rabies management decision-making in real time. The value of enhanced surveillance as a complement to public health surveillance was best illustrated in Ohio during 2007, where 19 rabies cases were detected that were critical for the formulation of focused contingency actions for controlling rabies in this strategically key area. Diverse complexities and challenges are commonplace when applying ORV to control rabies in wild meso-carnivores. Nevertheless, intervention has resulted in notable successes, including the elimination of an arctic fox (Vulpes lagopus) rabies virus variant in most of southern Ontario, Canada, with ancillary benefits of elimination extending into Quebec and the northeastern US. Progress continues with ORV toward preventing the spread and working toward elimination of a unique variant of gray fox (Urocyon cinereoargenteus) rabies in west central Texas. Elimination of rabies in coyotes (Canis latrans) through ORV contributed to the US being declared free of canine rabies in 2007. Raccoon (Procyon lotor) rabies control continues to present the greatest challenges among meso-carnivore rabies reservoirs, yet to date intervention has prevented this variant from gaining a broad geographic foothold beyond ORV zones designed to prevent its spread from the eastern US. Progress continues toward the development and testing of new bait-vaccine combinations that increase the chance for improved delivery and performance in the diverse meso-carnivore rabies reservoir complex in the US. PMID:20027214

Slate, Dennis; Algeo, Timothy P; Nelson, Kathleen M; Chipman, Richard B; Donovan, Dennis; Blanton, Jesse D; Niezgoda, Michael; Rupprecht, Charles E

2009-01-01

162

Plants as bioindicators for archaeological prospection: a case of study from Domitian's Stadium in the Palatine (Rome, Italy).  

PubMed

In this study, we analyzed the relationship between buried archaeological remains (masonries, pavements, and ancient ruins) and spontaneous vegetation growing above them. We carried out several vegetation surveys in the Domitian's Stadium at the archaeological site of the Palatine (Rome). Vegetation data were collected using the Braun-Blanquet approach and elaborated using statistical analyses (cluster analysis) to assess the similarity among surveys. Structural, chorological, and ecological features of the plant communities were analyzed. Results showed that the vegetation responds significantly to the presence of sub-emerging ancient remains. The plant bioindication of this phenomenon occurs through the following floristic-vegetation variations: phenological alterations in single individuals (reduction in height, displacement of flowering/fruiting period), increase of annual species and decrease of perennial ones, decrease of total plant coverage, reduction of maturity level of the vegetation which remains blocked at a pioneer evolutive stage. The presence of sub-surfacing ruins manifests itself through the dominant occurrence of xerophilous and not-nitrophilous species (e.g., Hypochaeris achyrophorus L., Aira elegantissima Schur, Trifolium scabrum L. ssp. scabrum, Trifolium stellatum L., Plantago lagopus L., Medicago minima (L.) L., and Catapodium rigidum (L.) C.E. Hubb. ex Dony ssp. rigidum) and in a rarefaction of more mesophilous and nitrophilous species (e.g., Plantago lanceolata L., Trifolium pratense L. ssp. pratense, Trifolium repens L. ssp. repens, and Poa trivialis L.). Therefore, the vegetation can be used as bioindicator for the detection of buried ruins, contributing in the archaeological prospection for a general, fast, and inexpensive interpretation of the underground. PMID:23114916

Ceschin, S; Caneva, G

2013-06-01

163

A hierarchical model combining distance sampling and time removal to estimate detection probability during avian point counts  

USGS Publications Warehouse

Imperfect detection during animal surveys biases estimates of abundance and can lead to improper conclusions regarding distribution and population trends. Farnsworth et al. (2005) developed a combined distance-sampling and time-removal model for point-transect surveys that addresses both availability (the probability that an animal is available for detection; e.g., that a bird sings) and perceptibility (the probability that an observer detects an animal, given that it is available for detection). We developed a hierarchical extension of the combined model that provides an integrated analysis framework for a collection of survey points at which both distance from the observer and time of initial detection are recorded. Implemented in a Bayesian framework, this extension facilitates evaluating covariates on abundance and detection probability, incorporating excess zero counts (i.e. zero-inflation), accounting for spatial autocorrelation, and estimating population density. Species-specific characteristics, such as behavioral displays and territorial dispersion, may lead to different patterns of availability and perceptibility, which may, in turn, influence the performance of such hierarchical models. Therefore, we first test our proposed model using simulated data under different scenarios of availability and perceptibility. We then illustrate its performance with empirical point-transect data for a songbird that consistently produces loud, frequent, primarily auditory signals, the Golden-crowned Sparrow (Zonotrichia atricapilla); and for 2 ptarmigan species (Lagopus spp.) that produce more intermittent, subtle, and primarily visual cues. Data were collected by multiple observers along point transects across a broad landscape in southwest Alaska, so we evaluated point-level covariates on perceptibility (observer and habitat), availability (date within season and time of day), and abundance (habitat, elevation, and slope), and included a nested point-within-transect and park-level effect. Our results suggest that this model can provide insight into the detection process during avian surveys and reduce bias in estimates of relative abundance but is best applied to surveys of species with greater availability (e.g., breeding songbirds).

Amundson, Courtney L.; Royle, J. Andrew; Handel, Colleen M.

2014-01-01

164

Regional Distribution Shifts Help Explain Local Changes in Wintering Raptor Abundance: Implications for Interpreting Population Trends  

PubMed Central

Studies of multiple taxa across broad-scales suggest that species distributions are shifting poleward in response to global climate change. Recognizing the influence of distribution shifts on population indices will be an important part of interpreting trends within management units because current practice often assumes that changes in local populations reflect local habitat conditions. However, the individual- and population-level processes that drive distribution shifts may occur across a large, regional scale and have little to do with the habitats within the management unit. We examined the latitudinal center of abundance for the winter distributions of six western North America raptor species using Christmas Bird Counts from 1975–2011. Also, we considered whether population indices within western North America Bird Conservation Regions (BCRs) were explained by distribution shifts. All six raptors had significant poleward shifts in their wintering distributions over time. Rough-legged Hawks (Buteo lagopus) and Golden Eagles (Aquila chrysaetos) showed the fastest rate of change, with 8.41 km yr?1 and 7.74 km yr?1 shifts, respectively. Raptors may be particularly responsive to warming winters because of variable migration tendencies, intraspecific competition for nesting sites that drives males to winter farther north, or both. Overall, 40% of BCR population trend models were improved by incorporating information about wintering distributions; however, support for the effect of distribution on BCR indices varied by species with Rough-legged Hawks showing the most evidence. These results emphasize the importance of understanding how regional distribution shifts influence local-scale population indices. If global climate change is altering distribution patterns, then trends within some management units may not reflect changes in local habitat conditions. The methods used to monitor and manage bird populations within local BCRs will fundamentally change as species experience changes in distribution in response to climate change. PMID:24466253

Paprocki, Neil; Heath, Julie A.; Novak, Stephen J.

2014-01-01

165

Characterization of a New Epidemic Necrotic Pyoderma in Fur Animals and Its Association with Arcanobacterium phocae Infection  

PubMed Central

A new type of pyoderma was detected in Finnish fur animals in 2007. The disease continues to spread within and between farms, with severe and potentially fatal symptoms. It compromises animal welfare and causes considerable economic losses to farmers. A case-control study was performed in 2010–2011 to describe the entity and to identify the causative agent. Altogether 99 fur animals were necropsied followed by pathological and microbiological examination. The data indicated that the disease clinically manifests in mink (Neovison vison) by necrotic dermatitis of the feet and facial skin. In finnraccoons (Nyctereutes procyonoides), it causes painful abscesses in the paws. Foxes (Vulpes lagopus) are affected by severe conjunctivitis and the infection rapidly spreads to the eyelids and facial skin. A common finding at necropsy was necrotic pyoderma. Microbiological analysis revealed the presence of a number of potential causative agents, including a novel Streptococcus sp. The common finding from all diseased animals of all species was Arcanobacterium phocae. This bacterium has previously been isolated from marine mammals with skin lesions but this is the first report of A. phocae isolated in fur animals with pyoderma. The results obtained from this study implicate A. phocae as a potential causative pathogen of fur animal epidemic necrotic pyoderma (FENP) and support observations that the epidemic may have originated in a species -shift of the causative agent from marine mammals. The variable disease pattern and the presence of other infectious agents (in particular the novel Streptococcus sp.) suggest a multifactorial etiology for FENP, and further studies are needed to determine the environmental, immunological and infectious factors contributing to the disease. PMID:25302603

Nordgren, Heli; Aaltonen, Kirsi; Sironen, Tarja; Kinnunen, Paula M.; Kivistö, Ilkka; Raunio-Saarnisto, Mirja; Moisander-Jylhä, Anna-Maria; Korpela, Johanna; Kokkonen, Ulla-Maija; Hetzel, Udo; Sukura, Antti; Vapalahti, Olli

2014-01-01

166

Detection probability of cliff-nesting raptors during helicopter and fixed-wing aircraft surveys in western Alaska  

USGS Publications Warehouse

We conducted repeated aerial surveys for breeding cliff-nesting raptors on the Yukon Delta National Wildlife Refuge (YDNWR) in western Alaska to estimate detection probabilities of Gyrfalcons (Falco rusticolus), Golden Eagles (Aquila chrysaetos), Rough-legged Hawks (Buteo lagopus), and also Common Ravens (Corvus corax). Using the program PRESENCE, we modeled detection histories of each species based on single species occupancy modeling. We used different observers during four helicopter replicate surveys in the Kilbuck Mountains and five fixed-wing replicate surveys in the Ingakslugwat Hills near Bethel, AK. During helicopter surveys, Gyrfalcons had the highest detection probability estimate (p^;p^ 0.79; SE 0.05), followed by Golden Eagles (p^=0.68; SE 0.05), Common Ravens (p^=0.45; SE 0.17), and Rough-legged Hawks (p^=0.10; SE 0.11). Detection probabilities from fixed-wing aircraft in the Ingakslugwat Hills were similar to those from the helicopter in the Kilbuck Mountains for Gyrfalcons and Golden Eagles, but were higher for Common Ravens (p^=0.85; SE 0.06) and Rough-legged Hawks (p^=0.42; SE 0.07). Fixed-wing aircraft provided detection probability estimates and SEs in the Ingakslugwat Hills similar to or better than those from helicopter surveys in the Kilbucks and should be considered for future cliff-nesting raptor surveys where safe, low-altitude flight is possible. Overall, detection probability varied by observer experience and in some cases, by study area/aircraft type.

Booms, T.L.; Schempf, P.F.; McCaffery, B.J.; Lindberg, M.S.; Fuller, M.R.

2010-01-01

167

Estimates of annual survival, growth, and recruitment of a white-tailed ptarmigan population in Colorado over 43 years  

USGS Publications Warehouse

Long-term datasets for high-elevation species are rare, and considerable uncertainty exists in understanding how high-elevation populations have responded to recent climate warming. We present estimates of demographic vital rates from a 43-year population study of white-tailed ptarmigan (Lagopus leucura), a species endemic to alpine habitats in western North America. We used capture-recapture models to estimate annual rates of apparent survival, population growth, and recruitment for breeding-age ptarmigan, and we fit winter weather covariates to models in an attempt to explain annual variation. There were no trends in survival over the study period but there was strong support for age and sex effects. The average rate of annual growth suggests a relatively stable breeding-age population ( ? ¯ = 1.036), but there was considerable variation between years for both population growth and recruitment rates. Winter weather covariates only explained a small amount of variation in female survival and were not an important predictor of male survival. Cumulative winter precipitation was found to have a quadratic effect on female survival, with survival being highest during years of average precipitation. Cumulative winter precipitation was positively correlated with population growth and recruitment rates, although this covariate only explained a small amount of annual variation in these rates and there was considerable uncertainty among the models tested. Our results provide evidence for an alpine-endemic population that has not experienced extirpation or drastic declines. However, more information is needed to understand risks and vulnerabilities of warming effects on juveniles as our analysis was confined to determination of vital rates for breeding-age birds.

Wann, Greg; Aldridge, Cameron; Braun, Clait E.

2014-01-01

168

The time and duration of meiosis.  

PubMed

Ever since meiosis was recognized as a process there has been a continuing interest in its temporal aspects. Two main types of meiotic timing experiments have been conducted: first, experiments to estimate the duration of meiosis (and sometimes its stages); second, experiments to locate the sensitive stage(s) when exposure of meiocytes to various treatments can affect meiotic chromosome behaviour (e.g. pairing or recombination). Such experiments have played an important role in increasing our understanding of the meiotic process. The duration of meiosis has been estimated in about 70 organisms, including two prokaryotes (yeast and Chlamydomonas) and the following eukaryotes: 1 Basidiomycete (Coprinus lagopus), 2 Gymnosperms (Larix decidua and Thuja plicata gracilis). at least 39 angiosperms, and at least 26 animal species. The duration of female meiosis has been estimated in far fewer species than male meiosis. However, estimates of the duration of female meiosis are available for 6 angiosperms. Drosophila melanogaster, Xenopus laevis, and several mammals. Comparison of these data shows that the duration of meiosis is one of the most variable aspects of the meiotic process, ranging from less than 6 h in yeast to more than 40 years in the human female. Developmental holds at different stages of meiosis are common in plants and animals, and inevitably prolong the meiotic division. However, even among species without developmental holds, the duration of meiosis is very variable. For instance, in animals it ranges from about 1-2 days in male Drosophila melanogaster to more than 24 days in male Homo sapiens and several Orthopterans. Despite the large variation in the duration of meiosis three generalizations can be made: (i) first prophase is always very long compared with the remaining meiotic stages, (ii) the rate of meiotic development is very slow compared with the rate of development in dividing somatic meristem cells of the same organisms under the same conditions, (iii) the duration of meiosis is characteristic of the genotype and species. Four main factors have been recognized which effect or determine the duration of meiosis, namely (1) environmental factors (e.g. temperature); (2) nuclear DNA content; (3) ploidy level of the organism; and, (4) the genotype. Because nuclear DNA content plays a major role in determining the duration of meiosis, it has been suggested that DNA influences the rate of meiotic development in two ways: first through its informational content (the genotype), and second indirectly by the physical and mechanical effects of its mass independently of its informational content (i.e. the nucleotype). Thus, the observed duration of meiosis is the result of a complex genotype-nucleotype-environment interaction. With the obvious exception of variation caused by developmental holds, changes in the duration of meiosis usually involve proportional changes in the durations of all its stages... PMID:16285

Bennett, M D

1977-03-21

169

Wing geometry as a tool for discrimination of Obsoletus group (Diptera: Ceratopogonidae: Culicoides) in France.  

PubMed

In Europe, Culicoides chiopterus, Culicoides dewulfi, Culicoides obsoletus and Culicoides scoticus, which belongs to the subgenus Avaritia and Obsoletus group are the most proficient Bluetongue and Schmallenberg vectors. Within this group, correct identification based on morphological traits is difficult but essential to assess disease transmission risk. The development of new tools has revolutionized taxonomy (i.e. geometric morphometrics and molecular biology). Wing morphology is of primary importance to entomologists interested in systematics. Here, we report phenotypic differentiation patterns among the species above mentioned using a landmark-based geometric morphometric approach that efficiently identified C. chiopterus and C. dewulfi. Wing shape of the C. scoticus sample exhibited large specific variability. Based on landmarks and phylogenetic analyses (Maximum Parsimony), we suggest that Obsoletus group in Europe includes only C. obsoletus and C. scoticus. C. dewulfi and C. chiopterus are clearly excluded. Their shape seems closer to C. obsoletus that is why we suggest that only these two species should be grouped in the Obsoletus group. In addition, the concordance between phenetic clusters and phylogenies inferred from molecular data based on a fragment of the mtDNA COI gene and rDNA 28S suggests the existence of a strong signal in wing shape. These findings encourage us to use this powerful tool in taxonomic studies. PMID:24514019

Hajd Henni, L; Sauvage, F; Ninio, C; Depaquit, J; Augot, D

2014-01-01

170

The emergence of Schmallenberg virus across Culicoides communities and ecosystems in Europe.  

PubMed

Schmallenberg virus (SBV), a novel arboviral pathogen, has emerged and spread across Europe since 2011 inflicting congenital deformities in the offspring of infected adult ruminants. Several species of Culicoides biting midges (Diptera: Ceratopogonidae) have been implicated in the transmission of SBV through studies conducted in northern Europe. In this study Culicoides from SBV outbreak areas of mainland France and Italy (Sardinia) were screened for viral RNA. The role of both C. obsoletus and the Obsoletus complex (C. obsoletus and C. scoticus) in transmission of SBV were confirmed in France and SBV was also discovered in a pool of C. nubeculosus for the first time, implicating this species as a potential vector. While collections in Sardinia were dominated by C. imicola, only relatively small quantities of SBV RNA were detected in pools of this species and conclusive evidence of its potential role in transmission is required. In addition to these field-based studies, infection rates in colony-derived individuals of C. nubeculosus and field-collected C. scoticus are also examined in the laboratory. Rates of infection in C. nubeculosus were low, confirming previous studies, while preliminary examination of C. scoticus demonstrated that while this species can replicate SBV to a potentially transmissible level, further work is required to fully define comparative competence between species in the region. Finally, the oral competence for SBV of two abundant and widespread mosquito vector species in the laboratory is assessed. Neither Aedes albopictus nor Culex pipiens were demonstrated to replicate SBV to transmissible levels and appear unlikely to play a major role in transmission. Other vector competence data produced from studies across Europe to date is then comprehensively reviewed and compared with that generated previously for bluetongue virus. PMID:24698329

Balenghien, Thomas; Pagès, Nonito; Goffredo, Maria; Carpenter, Simon; Augot, Denis; Jacquier, Elisabeth; Talavera, Sandra; Monaco, Federica; Depaquit, Jérôme; Grillet, Colette; Pujols, Joan; Satta, Giuseppe; Kasbari, Mohamed; Setier-Rio, Marie-Laure; Izzo, Francesca; Alkan, Cigdem; Delécolle, Jean-Claude; Quaglia, Michela; Charrel, Rémi; Polci, Andrea; Bréard, Emmanuel; Federici, Valentina; Cêtre-Sossah, Catherine; Garros, Claire

2014-10-15

171

Seasonal dynamics of biting midges (Diptera: Ceratopogonidae: Culicoides), the potential vectors of bluetongue virus, in Sweden.  

PubMed

The outbreak of bluetongue (BT) in northern Europe 2006 initiated the monitoring of vectors, biting midges of the genus Culicoides in Sweden. In order to determine the diversity, distribution and seasonal dynamics of Culicoides, weekly collections were made during 2008 and during March-December 2009 using the Ondestepoort Veterinary Institute black light trap. Twenty sampling sites were selected in 12 provinces. In total of 30,704 Culicoides were collected in 2008 and 32,252 in 2009. The most abundant species were the potential vectors of BTV Culicoides obsoletus/C. scoticus that comprised of 77% of the total catches. Other biting midges collected were Culicoides impunctatus (9%), Culicoides grisescens (3%), Culicoides punctatus (2%), Culicoides chiopterus (2%) and Culicoides pulicaris (2%). Culicoides obsoletus/C. scoticus were most abundant during May-June and August-September. The majority of the species were active from March to November in 2008 and April to October in 2009. Species considered as potential vectors of bluetongue virus (BTV) occurred as far north as latitude 65°N (Kalix). PMID:21944873

Ander, M; Meiswinkel, R; Chirico, J

2012-02-28

172

Phenotypic differentiation and phylogenetic signal of wing shape in western European biting midges, Culicoides spp., of the subgenus Avaritia.  

PubMed

In the past decade biting midges of the subgenus Avaritia (Diptera: Ceratopogonidae) have been popular subjects of applied entomological studies in Europe owing to their implication as biological vectors in outbreaks of bluetongue and Schmallenberg viruses. This study uses a combination of cytochrome oxidase subunit I barcode sequencing and geometric morphometric analyses to investigate wing shape as a means to infer species identification within this subgenus. In addition the congruence of morphological data with different phylogenetic hypotheses is tested. Five different species of the subgenus Avaritia were considered in the study (C. obsoletus (Meigen); C. scoticus Kettle and Lawson; C. chiopterus (Meigen); C. dewulfi Goetghebuer and C. imicola (Kieffer)). The study demonstrated that over 90% of individuals could be separated correctly into species by their wing shape and that patterns of morphological differentiation derived from the geometric morphometric analyses were congruent with phylogenies generated from sequencing data. Morphological data produced are congruent with monophyly of the subgenus Avaritia and the exclusion of C. dewulfi from the group containing C. obsoletus, C. scoticus and C. chiopterus. The implications of these results and their importance in a wider context of integrating multiple data types to interpret both phylogeny and species characterization is discussed. PMID:24387691

Muñoz-Muñoz, F; Talavera, S; Carpenter, S; Nielsen, S A; Werner, D; Pagès, N

2014-09-01

173

Do Red Deer Stags (Cervus elaphus) Use Roar Fundamental Frequency (F0) to Assess Rivals?  

PubMed Central

It is well established that in humans, male voices are disproportionately lower pitched than female voices, and recent studies suggest that this dimorphism in fundamental frequency (F0) results from both intrasexual (male competition) and intersexual (female mate choice) selection for lower pitched voices in men. However, comparative investigations indicate that sexual dimorphism in F0 is not universal in terrestrial mammals. In the highly polygynous and sexually dimorphic Scottish red deer Cervus elaphus scoticus, more successful males give sexually-selected calls (roars) with higher minimum F0s, suggesting that high, rather than low F0s advertise quality in this subspecies. While playback experiments demonstrated that oestrous females prefer higher pitched roars, the potential role of roar F0 in male competition remains untested. Here we examined the response of rutting red deer stags to playbacks of re-synthesized male roars with different median F0s. Our results show that stags’ responses (latencies and durations of attention, vocal and approach responses) were not affected by the F0 of the roar. This suggests that intrasexual selection is unlikely to strongly influence the evolution of roar F0 in Scottish red deer stags, and illustrates how the F0 of terrestrial mammal vocal sexual signals may be subject to different selection pressures across species. Further investigations on species characterized by different F0 profiles are needed to provide a comparative background for evolutionary interpretations of sex differences in mammalian vocalizations. PMID:24386312

Garcia, Maxime; Charlton, Benjamin D.; Wyman, Megan T.; Fitch, W. Tecumseh; Reby, David

2013-01-01

174

Does covering of farm-associated Culicoides larval habitat reduce adult populations in the United Kingdom??  

PubMed Central

Culicoides biting midges (Diptera: Ceratopogonidae) are the biological vectors of a range of internationally important arboviruses of livestock, including bluetongue virus (BTV) and the recently emerging Schmallenberg virus (SBV). Culicoides species in the subgenus Avaritia (in the UK: Culicoides obsoletus Meigen, Culicoides scoticus Downes & Kettle, Culicoides dewulfi Goetghebuer and Culicoides chiopterus Meigen) have been implicated in BTV transmission in northern Europe and to a varying degree utilise cattle dung as a larval development substrate. The collection of cattle dung into heaps on farms provides a localised source of Culicoides emergence in close proximity to livestock. This study assesses the impact of covering dung heaps prior to the onset of adult Culicoides activity with the aim of reducing recruitment to the local adult populations at four livestock farms in England. Light suction trap catches of adult Culicoides from these farms were compared with those from four untreated control farms from a wide geographic range across the UK. It was demonstrated that implementing control of emergence from dung heaps did not have a significant impact upon the local adult subgenus Avaritia abundance at the treated farm holdings and that the onset of Culicoides activity was similarly unaffected. Use of this method in isolation is unlikely to have an effect in reducing the risk of BTV and SBV transmission. The implications of these results for control of farm-associated Culicoides in Europe are discussed. PMID:24472769

Harrup, L.E.; Gubbins, S.; Barber, J.; Denison, E.; Mellor, P.S.; Purse, B.V.; Carpenter, S.

2014-01-01

175

Does covering of farm-associated Culicoides larval habitat reduce adult populations in the United Kingdom?  

PubMed

Culicoides biting midges (Diptera: Ceratopogonidae) are the biological vectors of a range of internationally important arboviruses of livestock, including bluetongue virus (BTV) and the recently emerging Schmallenberg virus (SBV). Culicoides species in the subgenus Avaritia (in the UK: Culicoides obsoletus Meigen, Culicoides scoticus Downes & Kettle, Culicoides dewulfi Goetghebuer and Culicoides chiopterus Meigen) have been implicated in BTV transmission in northern Europe and to a varying degree utilise cattle dung as a larval development substrate. The collection of cattle dung into heaps on farms provides a localised source of Culicoides emergence in close proximity to livestock. This study assesses the impact of covering dung heaps prior to the onset of adult Culicoides activity with the aim of reducing recruitment to the local adult populations at four livestock farms in England. Light suction trap catches of adult Culicoides from these farms were compared with those from four untreated control farms from a wide geographic range across the UK. It was demonstrated that implementing control of emergence from dung heaps did not have a significant impact upon the local adult subgenus Avaritia abundance at the treated farm holdings and that the onset of Culicoides activity was similarly unaffected. Use of this method in isolation is unlikely to have an effect in reducing the risk of BTV and SBV transmission. The implications of these results for control of farm-associated Culicoides in Europe are discussed. PMID:24472769

Harrup, L E; Gubbins, S; Barber, J; Denison, E; Mellor, P S; Purse, B V; Carpenter, S

2014-03-17

176

Culicoides midges (diptera: ceratopogonidae) as vectors of orbiviruses in Slovakia.  

PubMed

In recent years, rapid spread of Culicoides-borne pathogens such as bluetongue (BT) and Schmallenberg viruses have been reported in Europe. In this study we examined the Culicoides populations in farms with wild and domestic ruminants in Eastern Slovakia with the aim to confirm the presence of biting midges serving as potential vectors of important pathogens. The main vector complexes were the Obsoletus complex (54%; n=4,209) and the Pulicaris complex (23%; n=1,796). To estimate the relative abundance of the cryptic species of the Obsoletus complex (Culicoides obsoletus, Culicoides scoticus and Culicoides montanus), we performed the multiplex polymerase chain reaction (PCR) based on ITS-2 and ITS-1 segments, on 125 midges randomly sampled. The relative abundance of C. obsoletus ranged from 5.26% in the farm with wild ruminants to 85.71% in another farm with cattle and sheep. A total of 112 pools of parous and gravid females belonging to the Obsoletus and Pulicaris complexes were tested for virus detection by the real-time reverse transcription polymerase chain reaction (RT-PCR) for BT virus, as well as for the Epizootic Hemorrhagic Disease Virus (EHDV), with negative results. PMID:25273963

Sarvašová, Adela; Goffredo, Maria; Sopoliga, Igor; Savini, Giovanni; Ko?išová, Alica

2014-01-01

177

Bloodmeal analysis reveals avian Plasmodium infections and broad host preferences of Culicoides (Diptera: Ceratopogonidae) vectors.  

PubMed

Changing environmental conditions and human encroachment on natural habitats bring human populations closer to novel sources of parasites, which might then develop into new emerging diseases. Diseases transmitted by host generalist vectors are of special interest due to their capacity to move pathogens into novel hosts. We hypothesize that humans using forests for recreation are exposed to a broad range of parasites from wild animals and their vectors. A corollary of this is that new vector-host, parasite-host, and vector-parasite associations could eventually develop. Thus, we expect to observe atypical vector-host associations. Using molecular bloodmeal analysis via amplification of the mtDNA COI gene we identified the vertebrate hosts of Culicoides (Diptera: Ceratopogonidae) species in a sub-urban forest of Southwestern Germany. Bloodmeals were also checked for haemosporidian infections by amplifying a fragment of the mtDNA cyt b gene. We identified a total of 20 Culicoides species, thirteen of which fed on humans. From 105 screened bloodmeals we obtained high quality sequences for 77 samples, 73 (94.8%) originated from humans, two from livestock (Bos taurus and Equus caballus), and two from wild birds (Sylvia atricapilla and Turdus merula). We found that four Culicoides species previously assumed to feed exclusively on either birds (C. kibunensis) or domestic mammals (C. chiopterus, C. deltus, C. scoticus) fed also on humans. A total of six Culicoides abdomens were infected with avian haemosporidian parasites (Plasmodium or Haemoproteus), four of those abdomens contained blood derived from humans. Our results suggest that parasites of wild animals may be transferred to humans through infectious bites of Culicoides vectors. Further, we show that Culicoides vectors believed to be a specialist on specific vertebrate groups can have plastic feeding preferences, and that Culicoides are susceptible to infection by Plasmodium parasites, though vector viability must still be experimentally demonstrated. PMID:22363557

Santiago-Alarcon, Diego; Havelka, Peter; Schaefer, Hinrich Martin; Segelbacher, Gernot

2012-01-01

178

Environmental drivers of Culicoides phenology: how important is species-specific variation when determining disease policy?  

PubMed

Since 2006, arboviruses transmitted by Culicoides biting midges (Diptera: Ceratopogonidae) have caused significant disruption to ruminant production in northern Europe. The most serious incursions involved strains of bluetongue virus (BTV), which cause bluetongue (BT) disease. To control spread of BTV, movement of susceptible livestock is restricted with economic and animal welfare impacts. The timing of BTV transmission in temperate regions is partly determined by the seasonal presence of adult Culicoides females. Legislative measures therefore allow for the relaxation of ruminant movement restrictions during winter, when nightly light-suction trap catches of Culicoides fall below a threshold (the 'seasonally vector free period': SVFP). We analysed five years of time-series surveillance data from light-suction trapping in the UK to investigate whether significant inter-specific and yearly variation in adult phenology exists, and whether the SVFP is predictable from environmental factors. Because female vector Culicoides are not easily morphologically separated, inter-specific comparisons in phenology were drawn from male populations. We demonstrate significant inter-specific differences in Culicoides adult phenology with the season of Culicoides scoticus approximately eight weeks shorter than Culicoides obsoletus. Species-specific differences in the length of the SVFP were related to host density and local variation in landscape habitat. When the Avaritia Culicoides females were modelled as a group (as utilised in the SFVP), we were unable to detect links between environmental drivers and phenological metrics. We conclude that the current treatment of Avaritia Culicoides as a single group inhibits understanding of environmentally-driven spatial variation in species phenology and hinders the development of models for predicting the SVFP from environmental factors. Culicoides surveillance methods should be adapted to focus on concentrated assessments of species-specific abundance during the start and end of seasonal activity in temperate regions to facilitate refinement of ruminant movement restrictions thereby reducing the impact of Culicoides-borne arboviruses. PMID:25386940

Searle, Kate R; Barber, James; Stubbins, Francesca; Labuschagne, Karien; Carpenter, Simon; Butler, Adam; Denison, Eric; Sanders, Christopher; Mellor, Philip S; Wilson, Anthony; Nelson, Noel; Gubbins, Simon; Purse, Bethan V

2014-01-01

179

Bloodmeal Analysis Reveals Avian Plasmodium Infections and Broad Host Preferences of Culicoides (Diptera: Ceratopogonidae) Vectors  

PubMed Central

Changing environmental conditions and human encroachment on natural habitats bring human populations closer to novel sources of parasites, which might then develop into new emerging diseases. Diseases transmitted by host generalist vectors are of special interest due to their capacity to move pathogens into novel hosts. We hypothesize that humans using forests for recreation are exposed to a broad range of parasites from wild animals and their vectors. A corollary of this is that new vector-host, parasite-host, and vector-parasite associations could eventually develop. Thus, we expect to observe atypical vector-host associations. Using molecular bloodmeal analysis via amplification of the mtDNA COI gene we identified the vertebrate hosts of Culicoides (Diptera: Ceratopogonidae) species in a sub-urban forest of Southwestern Germany. Bloodmeals were also checked for haemosporidian infections by amplifying a fragment of the mtDNA cyt b gene. We identified a total of 20 Culicoides species, thirteen of which fed on humans. From 105 screened bloodmeals we obtained high quality sequences for 77 samples, 73 (94.8%) originated from humans, two from livestock (Bos taurus and Equus caballus), and two from wild birds (Sylvia atricapilla and Turdus merula). We found that four Culicoides species previously assumed to feed exclusively on either birds (C. kibunensis) or domestic mammals (C. chiopterus, C. deltus, C. scoticus) fed also on humans. A total of six Culicoides abdomens were infected with avian haemosporidian parasites (Plasmodium or Haemoproteus), four of those abdomens contained blood derived from humans. Our results suggest that parasites of wild animals may be transferred to humans through infectious bites of Culicoides vectors. Further, we show that Culicoides vectors believed to be a specialist on specific vertebrate groups can have plastic feeding preferences, and that Culicoides are susceptible to infection by Plasmodium parasites, though vector viability must still be experimentally demonstrated. PMID:22363557

Santiago-Alarcon, Diego; Havelka, Peter; Schaefer, Hinrich Martin; Segelbacher, Gernot

2012-01-01

180

Are Bogs Reservoirs for Emerging Disease Vectors? Evaluation of Culicoides Populations in the Hautes Fagnes Nature Reserve (Belgium)  

PubMed Central

Several species of Culicoides (Diptera: Ceratopogonidae) biting midges serve as biological vectors for the bluetongue virus (BTV) and the recently described Schmallenberg virus (SBV) in northern Europe. Since their recent emergence in this part of the continent, these diseases have caused considerable economic losses to the sheep and cattle industries. Much data is now available that describe the distribution, population dynamics, and feeding habits of these insects. However, little is known regarding the presence of Culicoides in unusual habitats such as peaty marshes, nor their potential vector capacity. This study evaluated Culicoides biting midges present in the bogs of a Belgian nature reserve compared to those residing at a nearby cattle farm. Culicoides were trapped in 2011 at four different sites (broadleaved and coniferous forested areas, open environments, and at a scientific station) located in the Hautes Fagnes Nature Reserve (Belgium). An additional light trap was operated on a nearby cattle farm. Very high numbers of biting midges were captured in the marshy area and most of them (70 to 95%) were Culicoides impunctatus, a potential vector of BTV and other pathogens. In addition, fewer numbers of C. obsoletus/C. scoticus species, C. chiopterus, and C. dewulfi were observed in the bogs compared to the farm. The wet environment and oligotrophic nature of the soil were probably responsible for these changes in the respective populations. A total of 297,808 Culicoides midges belonging to 27 species were identified during this study and 3 of these species (C. sphagnumensis, C. clintoni and C. comosioculatus) were described in Belgium for the first time. PMID:23799137

Zimmer, Jean-Yves; Smeets, François; Simonon, Grégory; Fagot, Jean; Haubruge, Eric; Francis, Frédéric; Losson, Bertrand

2013-01-01

181

A cervid vocal fold model suggests greater glottal efficiency in calling at high frequencies.  

PubMed

Male Rocky Mountain elk (Cervus elaphus nelsoni) produce loud and high fundamental frequency bugles during the mating season, in contrast to the male European Red Deer (Cervus elaphus scoticus) who produces loud and low fundamental frequency roaring calls. A critical step in understanding vocal communication is to relate sound complexity to anatomy and physiology in a causal manner. Experimentation at the sound source, often difficult in vivo in mammals, is simulated here by a finite element model of the larynx and a wave propagation model of the vocal tract, both based on the morphology and biomechanics of the elk. The model can produce a wide range of fundamental frequencies. Low fundamental frequencies require low vocal fold strain, but large lung pressure and large glottal flow if sound intensity level is to exceed 70 dB at 10 m distance. A high-frequency bugle requires both large muscular effort (to strain the vocal ligament) and high lung pressure (to overcome phonation threshold pressure), but at least 10 dB more intensity level can be achieved. Glottal efficiency, the ration of radiated sound power to aerodynamic power at the glottis, is higher in elk, suggesting an advantage of high-pitched signaling. This advantage is based on two aspects; first, the lower airflow required for aerodynamic power and, second, an acoustic radiation advantage at higher frequencies. Both signal types are used by the respective males during the mating season and probably serve as honest signals. The two signal types relate differently to physical qualities of the sender. The low-frequency sound (Red Deer call) relates to overall body size via a strong relationship between acoustic parameters and the size of vocal organs and body size. The high-frequency bugle may signal muscular strength and endurance, via a 'vocalizing at the edge' mechanism, for which efficiency is critical. PMID:20808882

Titze, Ingo R; Riede, Tobias

2010-01-01

182

A Cervid Vocal Fold Model Suggests Greater Glottal Efficiency in Calling at High Frequencies  

PubMed Central

Male Rocky Mountain elk (Cervus elaphus nelsoni) produce loud and high fundamental frequency bugles during the mating season, in contrast to the male European Red Deer (Cervus elaphus scoticus) who produces loud and low fundamental frequency roaring calls. A critical step in understanding vocal communication is to relate sound complexity to anatomy and physiology in a causal manner. Experimentation at the sound source, often difficult in vivo in mammals, is simulated here by a finite element model of the larynx and a wave propagation model of the vocal tract, both based on the morphology and biomechanics of the elk. The model can produce a wide range of fundamental frequencies. Low fundamental frequencies require low vocal fold strain, but large lung pressure and large glottal flow if sound intensity level is to exceed 70 dB at 10 m distance. A high-frequency bugle requires both large muscular effort (to strain the vocal ligament) and high lung pressure (to overcome phonation threshold pressure), but at least 10 dB more intensity level can be achieved. Glottal efficiency, the ration of radiated sound power to aerodynamic power at the glottis, is higher in elk, suggesting an advantage of high-pitched signaling. This advantage is based on two aspects; first, the lower airflow required for aerodynamic power and, second, an acoustic radiation advantage at higher frequencies. Both signal types are used by the respective males during the mating season and probably serve as honest signals. The two signal types relate differently to physical qualities of the sender. The low-frequency sound (Red Deer call) relates to overall body size via a strong relationship between acoustic parameters and the size of vocal organs and body size. The high-frequency bugle may signal muscular strength and endurance, via a ‘vocalizing at the edge’ mechanism, for which efficiency is critical. PMID:20808882

Titze, Ingo R.; Riede, Tobias

2010-01-01

183

Feeding behaviour of Culicoides spp. (Diptera: Ceratopogonidae) on cattle and sheep in northeast Germany  

PubMed Central

Background Culicoides spp. play an important role in the transmission of several vector-borne pathogens such as Bluetongue and Schmallenberg virus in Europe. To better understand the biology of local Culicoides species, a study divided into three parts was performed in northeast Germany to elucidate the feeding activity patterns (study A), preferential landing and feeding sites (study B) and host feeding preferences (study C) of Culicoides spp. using cattle and sheep as baits. Methods In study A, the activity of Culicoides spp. was monitored over a 72 h period by collecting insects at regular intervals from the interior of drop traps with cattle or sheep standing inside. In study B, Culicoides spp. were directly aspirated from the coat and fleece of cattle and sheep during the peak activity period of Culicoides. In study C, Culicoides spp. were collected using drop traps with either cattle or sheep standing inside and located 10 m apart. Results In study A, 3,545 Culicoides midges belonging to 13 species were collected, peak activity was observed at sunset. In study B, 2,024 Culicoides midges were collected. A significantly higher number of midges was collected from the belly and flank of cattle in comparison to their head region. In study C, 3,710 Culicoides midges were collected; 3,077 (83%) originated from cattle and 633 (17%) from sheep. Nearly half (46.7%) of the midges collected from cattle were engorged, significantly more than the number of engorged midges collected from sheep (7.5%). Culicoides from the Obsoletus complex (C. obsoletus and C. scoticus) were the most common Culicoides species encountered, followed by C. punctatus. Other species identified were C. dewulfi, C. chiopterus, C. pulicaris, C. lupicaris, C. pallidicornis, C. subfascipennis, C. achrayi, C. stigma, C. griseidorsum and C. subfagineus, the last two species are reported for the first time in Germany. Engorged C. chiopterus were collected in relatively high numbers from sheep, suggesting that this species may have a preference for sheep. Conclusions An insight into the feeding behaviour of local Culicoides species under field conditions in northeast Germany was obtained, with implications for the implementation of control measures and midge-borne disease risk analysis. PMID:24438698

2014-01-01

184

Reproductive performance of pubertal red deer (Cervus elaphus) hinds: effects of genetic introgression of wapiti subspecies on pregnancy rates at 18 months of age.  

PubMed

Low reproductive productivity of young red deer (Cervus elaphus) hinds on New Zealand deer farms appears to reflect high incidences of puberty failure at 16 months of age. This is despite the general attainment of average liveweights 15-25 kg in excess of the accepted minimum threshold for puberty in subspecies of western European origin (scoticus, elaphus and hippelaphus) that form the basis of the national herd. The present study tests the hypotheses that introgression of the larger North American wapiti subspecies (nelsoni, manitobensis and roosevelti) into breeding herds (1) can be assessed from morphological features of individuals, (2) that there is a relationship between the level of wapiti parentage and non-pregnancy rate at 18 months of age (a proxy for puberty failure) and (3) that minimum liveweight thresholds for puberty increase with increasing levels of wapiti parentage. A total of 4329 18-month-old hinds across four "red" deer farms in southern New Zealand were scanned for pregnancy status. Each hind was assigned a wapiti score (WS) as a subjective assessment of the obviousness of wapiti features. Various body measurements were additionally recorded for each hind. A hair sample was collected for DNA analysis (14 markers) to objectively assign subspecies pedigree (i.e. "Elkmeter") on a subset of 1258 individuals. A total of 506 (11.7%) hinds were not pregnant at 18 months of age with rates varying between 4.1 and 37.3% between farms and years. Mean WS differed significantly between farms and reflected the genetic management policy of each farm. WS was positively correlated to Elkmeter for each farm/year (<0.05) although regression slopes varied significantly. WS was able to be adjusted for these differences to assign a corrected WS (CWS) for all 4329 individuals that estimated the proportion wapiti parentage. Discriminant analysis of morphological variables relative to Elkmeter supported the first hypothesis and showed that shoulder height and body length were good indicators of the degree of wapiti parentage within individuals. This enabled the development of an objective estimate of wapiti parentage (EWP). The actual level of such parentage within herds ranged from <5 to >55%. There was a significant negative association between wapiti parentage and pregnancy, which was strongly influenced by liveweight, supporting the second and third hypotheses. This was manifest as marked displacement of pregnancy probability curves in relation to liveweight between genotype groups, particularly for those groups with >20% wapiti parentage. For example, predicted threshold liveweights required to achieve a 90% pregnancy rate for EWP values that represent 0, 10, 20, 30, 40 and 50% wapiti parentage were 81, 81, 85, 106, 127 and approximately 137 kg, respectively. Within the study herds, the majority of hinds of 0-20% wapiti parentage exceeded the predicted 90% threshold liveweights for their genotype cohort. However, hinds with higher levels of wapiti parentage generally fell below the predicted threshold for their genotype group. The data strongly suggest that under liveweight performance levels measured for red deer, hinds with >20% wapiti parentage are at high risk of puberty failure. PMID:16298276

Asher, G W; Archer, J A; Scott, I C; O'Neill, K T; Ward, J; Littlejohn, R P

2005-12-01