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1

Spatial distribution of genetic relatedness in a moorland population of red grouse ( Lagopus lagopus scoticus )  

Microsoft Academic Search

Several aspects of the ecology and biology of red grouse (Lagopus lagopus scoticus) could prevent the complete admixture of genes within and between populations. Male red grouse display a high degree of natal philopatry, are territorial, and show less aggression to kin than to non-kin. Such factors acting in combination predict limited male-mediated gene flow, which will promote social structure

STUART B PIERTNEY; ANDREW D. C MacCOLL; XAVIER LAMBIN; ROBERT MOSS; JOHN F DALLAS

1999-01-01

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

Temporal changes in kin structure through a population cycle in a territorial bird, the red grouse Lagopus lagopus scoticus  

Microsoft Academic Search

Populations of red grouse (Lagopus lagopus scoticus) undergo regular multiannual cycles in abundance. The 'kinship hypothesis' posits that such cycles are caused by changes in kin structure among territorial males producing delayed density-dependent changes in aggres- siveness, which in turn influence recruitment and regulate density. The kinship hypothesis makes several specific predictions about the levels of kinship, aggressiveness and recruitment

STUART B. PIERTNEY; XAVIER LAMBIN; ANDREW D. C. MACCOLL; KERRY LOCK; PHILIP J. BACON; JOHN F. DALLAS; FIONA LECKIE; FRANCOIS MOUGEOT; PAUL A. RACEY; STEVE REDPATH; ROBERT MOSS

2008-01-01

4

The role of invertebrates in the diet, growth and survival of red grouse (Lagopus lagopus scoticus) chicks  

Microsoft Academic Search

The role of diet on the growth, survival and movement of red grouse Lagopus lagopus scoticus chicks was examined. We compared two areas of moorland in Scotland: a dry heath with a low density of red grouse and poor chick survival; and a wetter heath\\/bog with relatively higher red grouse numbers and higher rates of chick survival. There were no

K. J. Park; P. A. Robertson; S. T. Campbell; R. Foster; Z. M. Russell; D. Newborn; P. J. Hudson

2001-01-01

5

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

6

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

7

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

8

Testosterone and autumn territorial behavior in male red grouse Lagopus lagopus scoticus  

Microsoft Academic Search

In many bird species, males exhibit territorial aggression outside the breeding season, when testosterone concentrations are low and may not regulate territorial behaviors. The hormonal regulation of aggression at this time of year has only been studied in passerine birds. Here, we investigated the role of testosterone in the regulation of aggression in a non-passerine bird, the red grouse Lagopus

François Mougeot; Alistair Dawson; Steve M. Redpath; Fiona Leckie

2005-01-01

9

Genetic diversity and management of Nearctic rock ptarmigan (Lagopus mutus)  

E-print Network

Genetic diversity and management of Nearctic rock ptarmigan (Lagopus mutus) Karen Holder, Robert Montgomerie, and Vicki L. Friesen Abstract: Though the rock ptarmigan, Lagopus mutus (Montin, 1776: Lagopus mutus evermanni (Elliot, 1896) on Attu I., Alaska, Lagopus mutus welchi (Brewster, 1885

Montgomerie, Bob

10

Reproductive defence priorities of male willow ptarmigan ( Lagopus lagopus ): enhancing mate survival or extending paternity options?  

Microsoft Academic Search

Cock willow ptarmigan (Lagopus lagopus) closely guard their mates from predators and conspecific males, and vigorously defend their nests and young. In view of potential costs and benefits of behavioural guarding descisions, I designed a test to examine if, when and how males altered defence priorities. Cock willow ptarmigan were very attentive to their mates throughout the breeding season, unaccompanied

Kathy Martin

1984-01-01

11

STANDARD SAMPLING TECHNIQUES UNDERESTIMATE PREVALENCE OF AVIAN HEMATOZOA IN WILLOW PTARMIGAN (LAGOPUS LAGOPUS)  

Microsoft Academic Search

ABSTRACT: A total of 68 willow ptarmigan (Lagopus lagopus L.) was collected during September 1995 from two localities in Troms County, northern Norway. Thin blood smears were prepared and examined for blood parasites. Of the 68 willow ptarmigan examined, 94% harbored one or more species of hematozoa. There were four (6%), 44 (65%), 16 (24%), and four (6%) birds infected

Per R. Holmstad; Ali Anwar; Tatjana Iezhova; Arne Skorping

12

Detection of herpesvirus DNA in Arctic foxes ( Vulpes lagopus; syn. Alopex lagopus) with fatal encephalitis  

Microsoft Academic Search

A captive breeding programme for the Fennoscandian Arctic fox (Vulpes lagopus; syn. Alopex lagopus) failed due to fatal encephalitis. The aim of this study was to identify the causative agent. Viral nucleic acid was detected by PCR and in situ hybridization in the brain of affected foxes. The results suggest that a herpesvirus might be the causative agent. Whether this

F. Widén; E. Sundström; D. Gavier-Widén; A. L. Berg; B. Dillner; M. Berg

13

Behavioural effects of cadmium (Cd) in free-living willow ptarmigan ( Lagopus lagopus )  

Microsoft Academic Search

The objective of this study was to examine effects of sublethal cadmium (Cd) contamination on parental behaviour and chick\\u000a survival in willow ptarmigan (Lagopus lagopus) in an area that does not have high environmental levels of Cd due to geology but have high environmental levels of Cd due\\u000a to anthropogenic deposition and acidification. One group of willow ptarmigan hens were

Hans Chr. Pedersen; Asgeir Lorås; Rolf A. Andersen; Bjørn M. Jenssen

2010-01-01

14

Detection of herpesvirus DNA in Arctic foxes (Vulpes lagopus; syn. Alopex lagopus) with fatal encephalitis.  

PubMed

A captive breeding programme for the Fennoscandian Arctic fox (Vulpes lagopus; syn. Alopex lagopus) failed due to fatal encephalitis. The aim of this study was to identify the causative agent. Viral nucleic acid was detected by PCR and in situ hybridization in the brain of affected foxes. The results suggest that a herpesvirus might be the causative agent. Whether this infection also occurs in free-living Arctic foxes is unknown. PMID:21546045

Widén, F; Sundström, E; Gavier-Widén, D; Berg, A L; Dillner, B; Berg, M

2012-06-01

15

HELMINTHS FROM WILLOW GROUSE (Lagopus lagopus) IN TWO LOCALITIES IN NORTH NORWAY  

Microsoft Academic Search

A total of 77 adult and 123 juvenile willow grouse (Lagopus \\/agopus) from the island of Karls#{246}y, and 75 adult and 63 juvenile willow grouse from Sennaland on themainland of North Norway were examined forhelminths.Raillictinaurogalli and Hymcno\\/epis microps, and Ascaridia compar and Syngamus trachea were found. All fourspeciesoccurredregularlyingrousefrom Karls#{246}y between Apriland September- October, but only H. microps was frequentlyfound in

KATHRIN WISSLER; ODD HALVORSEN

1977-01-01

16

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

17

IMMUNIZATION OF ARCTIC FOXES (ALOPEX LAGOPUS) WITH ORAL RABIES VACCINE  

Microsoft Academic Search

Arcticfoxes (Alopex lagopus) were successfully immunized against rabies using an orally-administered, liquid SAD-BHK21 live virus vaccine in a sausage bait. Immunization was determined by serologic response and by resistance to challenge with an arctic rabies virus strain. Virus was not shed in saliva following oral vaccination, indicating that arctic foxes would not infect other foxes after ingesting this vaccine. High

Erich H. Follmann; Donald G. Ritter; George M. Baer

18

Sequence Polymorphism in Candidate Genes for Differences in Winter Plumage between Scottish and Scandinavian Willow Grouse (Lagopus lagopus)  

PubMed Central

Background Population variation in the degree of seasonal polymorphism is rare in birds, and the genetic basis of this phenomenon remains largely undescribed. Both sexes of Scandinavian and Scottish Willow grouse (Lagopus lagopus) display marked differences in their winter phenotypes, with Scottish grouse retaining a pigmented plumage year-round and Scandinavian Willow grouse molting to a white morph during winter. A widely studied pathway implicated in vertebrate pigmentation is the melanin system, for which functional variation has been characterised in many taxa. Methodology/Principal Findings We sequenced coding regions from four genes involved in melanin pigmentation (DCT, MC1R, TYR and TYRP1), and an additional control involved in the melanocortin pathway (AGRP), to investigate the genetic basis of winter plumage in Lagopus. Despite the well documented role of the melanin system in animal coloration, we found no plumage-associated polymorphism or evidence for selection in a total of ?2.6 kb analysed sequence. Conclusions/Significance Our results indicate that the genetic basis of alternating between pigmented and unpigmented seasonal phenotypes is more likely explained by regulatory changes controlling the expression of these or other loci in the physiological pathway leading to pigmentation. PMID:20428241

Skoglund, Pontus; Höglund, Jacob

2010-01-01

19

Bioindicators of the health of arctic foxes. [Alopex lagopus  

SciTech Connect

Analyses were made of blood chemistry profiles and liver cytochemical components (ribonucleic acid, protein and glycogen) of captive arctic foxes (Alopex lagopus) maintained on either a protein-sufficient or deficient diet. Protein-deficient foxes exhibited a marked decrease in serum urea nitrogen (UN) levels and in hepatocyte ribonucleic acid (RNA) and protein contents. Comparison of blood profiles between free-ranging and pre-treatment captive foxes yielded several differences. A number of blood components, notably those used as tests of liver function, were negatively correlated with hepatocyte RNA levels. Results support the utility of using both blood chemical and tissue histochemical analyses to ascertain the health of animals.

Penman, J.A.; Garrott, R.A.; Eberhardt, L.E.; Anthony, A.; Rothenbacher, H.; Storm, G.L.; Tzilkowski, W.M.

1980-12-30

20

The pervalence of caecal threadworms ( Trichostrongylus tenuis ) in red grouse ( Lagopus lagopus scoticus )  

Microsoft Academic Search

Ninety percent of wild red grouse examined carried threadworms in their intenstinal caeca. Old birds had 30 times as many worms as young birds. Some infections were as high as 30,000 worms. The occurrence of worms in old grouse conformed to the negative binomial distribution.

George R. Wilson

1983-01-01

21

General properties of predictive population models in red grouse ( Lagopus lagopus scoticus )  

Microsoft Academic Search

The general properties of an empirical predictive model of population fluctuations in red grouse are discussed. The model incorporates two observed time-lagged relationships between (a) chick production and spring numbers two years earlier, and (b) overwinter survival and numbers in spring one year earlier. The model produced oscillations which were slowly damped with a period of nine years. The addition

P. Rothery; R. Moss; A. Watson

1984-01-01

22

Territorial behaviour and population dynamics in red grouse Lagopus lagopus scoticus. I. Population experiments  

Microsoft Academic Search

Summary 1. According to the 'territorial behaviour' hypothesis, population cycles of red grouse are caused by delayed density-dependent changes in the aggressiveness of territorial cocks. We report here on a replicated population experiment testing assumptions of this hypothesis. 2. We used testosterone implants to increase aggressiveness of cocks for 3 months during autumn, when recruitment and territory establishment take place.

Francois Mougeot; Steve M. Redpath; Robert Moss; Jason Matthiopoulos; Peter J. Hudson

2003-01-01

23

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

Microsoft Academic Search

Sexual ornaments might reliably indicate the ability to cope with parasites and diseases, and a better ability to mount a\\u000a primary inflammatory response to a novel challenge. Carotenoid-based ornaments are amongst the commonest sexual signals of\\u000a birds and often influence mate choice. Because carotenoids are immuno-stimulants, signallers may trade-off allocating these\\u000a to ornamental colouration or using them for immune responses,

Francois Mougeot

2008-01-01

24

Experimentally increased aggressiveness reduces population kin structure and subsequent recruitment in red grouse Lagopus lagopus scoticus  

Microsoft Academic Search

Summary 1. According to the 'territorial behaviour' hypothesis, red grouse population cycles are caused by delayed density-dependent changes in male aggressiveness influencing recruitment. These lagged changes in aggressiveness might be caused by changes in the kin structuring of male populations and differential aggressive behaviour between kin and non-kin ('kinship' hypothesis). 2. A population-level manipulation of male aggressiveness in autumn affected

FRANÇOIS MOUGEOT; STUART B. PIERTNEY; FIONA LECKIE; SHARON EVANS; ROBERT MOSS; STEVE M. REDPATH; PETER J. HUDSON

2005-01-01

25

Preventing a population decline of red grouse ( Lagopus lagopus scoticus ) by manipulating density  

Microsoft Academic Search

Summary This experiment tested whether a cyclic-type population decline can be prevented by removing territorial cock red grouse to keep breeding density below peak levels. The manipulated population did not decline, despite big decreases in food and breeding success, and more parasitic threadworms per bird than on the control.

A. Watson; R. Moss; R. Parr; I. B. Trenholm; A. Robertson

1988-01-01

26

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

27

Spontaneous rickets in the wild arctic fox Alopex lagopus  

SciTech Connect

Normal and rachitic, skeletally immature arctic foxes (Alopex lagopus) were subjected to physical examination, roentgenographic studies, and in some cases histologic studies. The involved animals had active rickets coupled with antecedent normal diaphyseal bone formation. Evaluation of all the long bones showed highly variable manifestations of the disease, which undoubtedly reflect different rates of physeal endochondral transformation and metaphyseal remodeling. Histologic examination showed distinct patterns of widening of the physes and variable osteodystrophy in the trabecular and cortical bone of the metaphyses and epiphyseal ossification centers. These aforementioned factors certainly would necessitate different regional calcium needs and, therefore, different regional responses to an overall calcium deficiency. The physes involved in the most rapid growth rates in this period showed the most widening of the growth plate, and the most dystrophic changes in the metaphysis. Skeletal injuries, including metaphyseal fractures and slow-down of longitudinal growth (particularly in the ulna) were also evident. Because of apparent dietary differences in the affected and normal fox kits, this juvenile-onset disease was presumed due to calcium-deficient intake following weaning. To the best of our knowledge this is the first report of spontaneously occurring rickets in a wild animal in its natural habitat. There are several possible mechanisms for the variable widening of the physis and the loss of bone mineralization in these fox kits: calcium-deficient diet, binding of calcium in the bowel by high phosphorus intake, secondary hyperparathyroidism, and vitamin A toxicity.

Ogden, J.A.; Conlogue, G.J.

1981-10-01

28

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

29

First isolate of Toxoplasma gondii from arctic fox (Vulpes lagopus) from Svalbard  

Technology Transfer Automated Retrieval System (TEKTRAN)

Cats are considered essential for the maintenance of Toxoplasma gondii in nature. However, T. gondii infection has been reported in arctic fox (Vulpes lagopus) from the Svalbard high arctic archipelago where felids are virtually absent. To identify the potential source of T. gondii, we attempted to ...

30

An overlooked boreal clubmoss Lycopodium lagopus (Laest. ex Hartm.) Zinserl. ex Kusen. (Lycopodiaceae) in Britain  

Microsoft Academic Search

Lycopodium lagopus (Laest. ex Hartm.) Zinserl. ex Kusen. (syn. L. clavatum L. subsp. monostachyon (Grev. & Hooker) Selander), a widespread circum- arctic taxon, is reported from Britain for the first time. First collected in the 19th century, it had been dismissed as L. clavatum and its significance not recognised. The appropriate taxonomic rank for this plant has long proved controversial

F. J. RUMSEY

31

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

32

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

33

Barking foxes, Alopex lagopus: field experiments in individual recognition in a territorial mammal  

Microsoft Academic Search

During field studies on a wild population of Arctic foxes, Alopex lagopus, on the Commander Island Mednyi (Northern Pacific) we examined whether acoustic long-distance signals were used for individual recognition. Barks of 10 individually known animals from five neighbouring groups were tape recorded. The spectral characteristics of the barks were described in terms of averaged 1\\/12 octave spectra.With a discriminant

Karl-Heinz Frommolt; Mikhail E. Goltsman; David W. Macdonald

2003-01-01

34

MAMMALIAN SPECIES No. 713, pp. 110, 3 figs. Alopex lagopus. By Alexandra M. Audet, C. Brian Robbins, and Serge Larivie`re  

E-print Network

:40. Type species Canis lagopus. Alopex Kaup, 1829:85. Type species C. lagopus Linnaeus. Vulpes Oken, 1816 been considered a subgenus of Vulpes (Bobrinskii 1965) and a subgenus of Canis (Van Gelder 1978 locality ``Gron- land'' ( Greenland). Vulpes arctica Oken, 1816:1033. Unavailable name (Hemmings 1956

Hayssen, Virginia

35

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

36

Rising burden of immature sheep ticks (Ixodes ricinus) on red grouse (Lagopus lagopus scoticus) chicks in the Scottish uplands  

Microsoft Academic Search

The sheep tick Ixodes ricinus (L.) (Acari: Ixodidae) is an ectoparasite of major economic and pathogenic importance in Scotland. Its distribution in the Scottish uplands is assumed to be governed by the abundance and distribution of its definitive hosts (deer and sheep) and climatic variables such as temperature and rainfall. As the numbers of its major host in Scotland, red

A. D. K IRBY; T. G. B ENTON; P. J. H UDSON

2004-01-01

37

Pearsonema (syn Capillaria) plica associated cystitis in a Fennoscandian arctic fox (Vulpes lagopus: a case report.  

PubMed

The bladderworm Pearsonema (syn Capillaria) plica affects domestic dogs and wild carnivores worldwide. A high prevalence in red foxes (Vulpes vulpes) has been reported in many European countries. P. plica inhabits the lower urinary tract and is considered to be of low pathogenic significance in dogs mostly causing asymptomatic infections. However, a higher level of pathogenicity has been reported in foxes. A severe cystitis associated with numerous bladderworms was found in a captive arctic fox (Vulpes lagopus) originating from the endangered Fennoscandian arctic fox population. To our knowledge this is the first description of P. plica infection in an arctic fox. PMID:20540788

Fernández-Aguilar, Xavier; Mattsson, Roland; Meijer, Tomas; Osterman-Lind, Eva; Gavier-Widén, Dolores

2010-01-01

38

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

39

Vector-borne pathogens in arctic foxes, Vulpes lagopus, from Canada.  

PubMed

Because of the relatively low biodiversity within arctic ecosystems, arctic foxes, Vulpes lagopus, could serve as sentinels for the study of changes in the ecology of vector-borne zoonotic pathogens. The objective of this study was to determine the molecular prevalence of 5 different genera of vector borne pathogens (Anaplasma, Babesia, Bartonella, Ehrlichia, and Hemotropic Mycoplasma spp.) using blood collected from 28 live-trapped arctic foxes from the region of Karrak Lake, Nunavut, Canada. Bartonella henselae (n?=?3), Mycoplasma haemocanis (n?=?1), Ehrlichia canis (n?=?1), and an Anaplasma sp. (n?=?1) DNA were PCR amplified and subsequently identified by sequencing. This study provides preliminary evidence that vector borne pathogens, not typically associated with the arctic ecosystem, exist at low levels in this arctic fox population, and that vector exposure, pathogen transmission dynamics, and changes in the geographic distribution of pathogens over time should be investigated in future studies. PMID:25596149

Mascarelli, Patricia E; Elmore, Stacey A; Jenkins, Emily J; Alisauskas, Ray T; Walsh, Mary; Breitschwerdt, Edward B; Maggi, Ricardo G

2015-04-01

40

Preliminary evaluation of Raboral V-RG® oral rabies vaccine in Arctic foxes (Vulpes lagopus).  

PubMed

We tested the Raboral V-RG® recombinant oral rabies vaccine for its response in Arctic foxes (Vulpes lagopus), the reservoir of rabies virus in the circumpolar North. The vaccine, which is currently the only licensed oral rabies vaccine in the United States, induced a strong antibody response and protected foxes against a challenge of 500,000 mouse intracerebral lethal dose 50% of an Arctic rabies virus variant. However, one unvaccinated control fox survived challenge with rabies virus, either indicating a high resistance of Arctic foxes to rabies infection or a previous exposure that induced immunity. This preliminary study suggested that Raboral V-RG vaccine may be efficacious in Arctic foxes. PMID:22102679

Follmann, Erich; Ritter, Don; Swor, Rhonda; Dunbar, Mike; Hueffer, Karsten

2011-10-01

41

Spring density and summer habitat use of alpine rock ptarmigan Lagopus muta helvetica in the southeastern Alps  

Microsoft Academic Search

In the Alps tourism, land-use practices and climate change may cause a loss of suitable habitat of rock ptarmigan (Lagopus muta helvetica). Hence, there is a need for basic research on population densities and habitat requirements of this species as a basis for\\u000a long-term monitoring studies. So far, in the Austrian Alps, no accurate data on densities and trends of

Margit Zohmann; Mark Wöss

2008-01-01

42

Adiponectin and peptide YY in the fasting blue fox (Alopex lagopus).  

PubMed

Adiponectin (Acrp30) and peptide YY (PYY) are weight-regulatory hormones participating in the control of energy homeostasis. This study investigated the effects of long-term wintertime fasting on plasma Acrp30 and PYY levels in the carnivorous blue fox, a farm-bred variant of the arctic fox (Alopex lagopus). Plasma Acrp30 and PYY concentrations were determined with radioimmunoassays during a 22-day period of fasting, which led to a 20.3% reduction in body mass of the animals (n=32). Sixteen fed blue foxes served as the control group. Acrp30 and PYY were present in blue fox plasma at similar or lower levels as reported previously for other mammals. Fasting had no acute effects on Acrp30 or PYY concentrations of the blue foxes. However, the Acrp30 levels of the fasted blue foxes were 24%-48% higher than in the fed animals between days 8-22 of fasting. Fasted blue foxes also had 6.2-fold higher plasma PYY concentrations after 15 days of fasting. Acrp30 and PYY seem to play roles in the body weight-regulation of the blue fox during long-term fasting, but their specific functions and physiological significance remain to be determined. PMID:15748866

Mustonen, Anne-Mari; Pyykönen, Teija; Nieminen, Petteri

2005-02-01

43

Physiological adaptations to fasting in an actively wintering canid, the Arctic blue fox (Alopex lagopus).  

PubMed

This study investigated the physiological adaptations to fasting using the farmed blue fox (Alopex lagopus) as a model for the endangered wild arctic fox. Sixteen blue foxes were fed throughout the winter and 32 blue foxes were fasted for 22 d in Nov-Dec 2002. Half of the fasted blue foxes were food-deprived again for 22 d in Jan-Feb 2003. The farmed blue fox lost weight at a slower rate (0.97-1.02% body mass d(-1)) than observed previously in the arctic fox, possibly due to its higher initial body fat content. The animals experienced occasional fasting-induced hypoglycaemia, but their locomotor activity was not affected. The plasma triacylglycerol and glycerol concentrations were elevated during phase II of fasting indicating stimulated lipolysis, probably induced by the high growth hormone concentrations. The total cholesterol, HDL- and LDL-cholesterol, urea, uric acid and total protein levels and the urea:creatinine ratio decreased during fasting. Although the plasma levels of some essential amino acids increased, the blue foxes did not enter phase III of starvation characterized by stimulated proteolysis during either of the 22-d fasting procedures. Instead of excessive protein catabolism, it is liver dysfunction, indicated by the increased plasma bilirubin levels and alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase activities, that may limit the duration of fasting in the species. PMID:16358268

Mustonen, Anne-Mari; Pyykönen, Teija; Puukka, Matti; Asikainen, Juha; Hänninen, Sari; Mononen, Jaakko; Nieminen, Petteri

2006-01-01

44

Effects of fasting and exogenous melatonin on annual rhythms in the blue fox (Alopex lagopus).  

PubMed

The arctic fox (Alopex lagopus) is a winter-active inhabitant of the high arctic with extreme fluctuations in photoperiod and food availability. The blue fox is a semi-domesticated variant of the wild arctic fox reared for the fur industry. In this study, 48 blue foxes were followed for a year in order to determine the effects of exogenous melatonin and wintertime food deprivation on their reproductive and thyroid axes. Half of the animals were treated with continuous-release melatonin capsules in July 2002, and in November-January, the animals were divided into three groups and either fed continuously or fasted for one or two 22-day periods. Food deprivation decreased the plasma triiodothyronine and thyroxine concentrations probably in order to preserve energy due to a decreased metabolic rate. The same was observed in the plasma testosterone levels of the males but not in the plasma estradiol concentrations of the females. Exogenous melatonin advanced the autumn moult and seasonal changes in the voluntary food intake. It also advanced the onset of the testosterone peak in the males. The plasma estradiol levels of the females were unaffected, but the progesterone levels peaked more steeply in the sham-operated females. Melatonin exerted a strong influence not only on the reproductive axis of the males but also on the seasonal food intake. The species seemed quite resistant to periodic involuntary food deprivation. PMID:15528167

Nieminen, Petteri; Pyykönen, Teija; Asikainen, Juha; Mononen, Jaakko; Mustonen, Anne-Mari

2004-10-01

45

Seasonal differences in jump performance in the Svalbard rock ptarmigan (Lagopus muta hyperborea).  

PubMed

Fat storage is essential to the survival of many bird species, providing energy reserves, but can have an effect on locomotor performance with an associated potential increase in predation risk. In particular, the ability to initiate flight through jumping is critical to predator avoidance and may be influenced by changes in body mass (Mb). Here we investigate seasonal differences in the jump take-off performance of high Arctic Svalbard rock ptarmigan (Lagopus muta hyperborea) resulting from around a 50% increase in Mb during winter as a result of fat deposition. Using force-plate data and videography, we reveal that, in the absence of alterations to take-off angle, winter Svalbard rock ptarmigan are unable to increase hind-limb power output during jumping to compensate for their increased Mb. As a result, peak take-off velocity is reduced by 42% and jump duration is also extended during winter. The consequences of reduced jumping performance upon Svalbard ptarmigan during winter may be relatively small given their low risk of predation during this season. It may be, however, that the observed reduction in jumping performance when fat may contribute to the sub-maximal pattern of fat acquisition observed in other bird species. PMID:24659246

Lees, John J; Folkow, Lars P; Codd, Jonathan R; Nudds, Robert L

2014-01-01

46

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

47

Cytotoxic and antioxidative activities of Plantago lagopus L. and characterization of its bioactive compounds.  

PubMed

Bioactivity guided isolation and characterization of phytoconstituents from the aerial parts of Plantago lagopus L. were performed to give a new insight into the usage of Plantago species in traditional medicine. The extract showed strong radical scavenging effects against DPPH, nitric oxide (NO) and superoxide (SO) radicals comparable to that of known antioxidants 3-t-butyl-4-hydroxyanisole, ascorbic acid (vitamin C), and quercetin in addition to its cytotoxic activities against HEP-2 (human larynx epidermoid carcinoma) and RD (human rhabdomyosarcoma) cell lines based on MTT assay for growth inhibition. The gallic acid equivalent total phenolic content of the plant was found to be 79.94 mg/g dry extract. Phenylethanoid glycosides, verbascoside and calceorioside A were isolated from the most active fraction and both compounds showed strong radical scavenging activity against tested radicals and cytotoxicity against HEP-2, RD and MCF-7 (human breast adenocarcinoma) cell lines. In addition apoptotic cell death was observed in histological analysis. Taken together, these findings suggest that verbascoside and calceorioside A may be used in cancer prevention. PMID:22289578

Harput, U Sebnem; Genc, Yasin; Saracoglu, Iclal

2012-05-01

48

Reduced metabolic cost of locomotion in Svalbard rock ptarmigan (Lagopus muta hyperborea) during winter.  

PubMed

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

49

Relative importance of male and territory quality in pairing success of male rock ptarmigan (Lagopus mutus)  

USGS Publications Warehouse

We studied pairing success in male rock ptarmigan (Lagopus mutus) in northern Alaska to learn whether males obtaining more females possessed phenotypic traits that influenced female choice directly, whether these traits permitted males to obtain territories favored by females, or whether both processes occurred. The number of females per male varied from zero to three. Several male and territory traits were significantly correlated with number of females per male. We used multiple regression to obtain a single measure of male quality and a single measure of territory quality. These measures of male and territory quality correlated with each other and with male pairing success. We used path analysis to separate direct effects of male quality on pairing success from indirect effects due to high-quality males obtaining high-quality territories. Both direct and indirect pathways had significant effects on pairing success, and direct and indirect effects of male traits on pairing success were about equal. This study illustrates an analytical approach for estimating the relative importance of direct and indirect causal relationships in natural systems.

Bart, Jonathan; Earnst, Susan L.

1999-01-01

50

Home ranges and movements of arctic fox (Alopex lagopus) in western Alaska  

USGS Publications Warehouse

During the period from 1985 to 1990, radio collars were attached to 61 arctic foxes (Alopex lagopus) in the coastal region of the Yukon-Kuskokwim Delta in western Alaska. Radio tracking using hand-held receivers from aircraft, and from fixed towers was conducted to determine daily and seasonal movements of foxes. Intensive radio tracking of 18 foxes from May through July indicated that males used larger areas (x=10.22i??6.18 km2) than females (x=4.57i??1.94 km2) regardless of breeding status. Generally foxes were relocated near (x=3.4i??2.4 km) their summer home ranges during other seasons of the year. There were no complex social groups of foxes among the marked population. Foxes did not have a definitive preference for any plant community, probably because of the even distribution and abundance of prey throughout all communities. Thirty foxes were relocated repeatedly during a period of at least 10 months, which included the denning season of one year and the breeding season of the next. Of 24 confirmed deaths of collared foxes, 16 were caused by shooting or trapping by local residents and 8 had unidentified causes. Maximum distance moved between relocations was 48.4 km. Males moved farther from initial capture sites in the winter following capture than did females, largely because of greater than 20 km movements by two foxes. There were no seasonal differences in movements between males and females.

Anthony, R.M.

1997-01-01

51

Biological Journal of the Linnean Society (1999), 68: 317331. With 6 figures Article ID: bijl.1999.0344, available online at http://www.idealibrary.com on  

E-print Network

in a moorland population of red grouse (Lagopus lagopus scoticus) STUART B. PIERTNEY1 , ANDREW D.C. MacCOLL1 Several aspects of the ecology and biology of red grouse (Lagopus lagopus scoticus) could prevent

Lambin, Xavier

1999-01-01

52

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

E-print Network

clusters; Kinship; Ordinary differential equations; Population cycles; Red grouse (Lagopus lagopus scoticus of territoriality (Watson and Jenkins, 1968) and philopatry (MacColl, 1998) in red grouse (Lagopus lagopus scoticus

Lambin, Xavier

2002-01-01

53

Correlates between Feeding Ecology and Mercury Levels in Historical and Modern Arctic Foxes (Vulpes lagopus)  

PubMed Central

Changes in concentration of pollutants and pathogen distribution can vary among ecotypes (e.g. marine versus terrestrial food resources). This may have important implications for the animals that reside within them. We examined 1) canid pathogen presence in an endangered arctic fox (Vulpes lagopus) population and 2) relative total mercury (THg) level as a function of ecotype (‘coastal’ or ‘inland’) for arctic foxes to test whether the presence of pathogens or heavy metal concentration correlate with population health. The Bering Sea populations on Bering and Mednyi Islands were compared to Icelandic arctic fox populations with respect to inland and coastal ecotypes. Serological and DNA based pathogen screening techniques were used to examine arctic foxes for pathogens. THg was measured by atomic absorption spectrometry from hair samples of historical and modern collected arctic foxes and samples from their prey species (hair and internal organs). Presence of pathogens did not correlate with population decline from Mednyi Island. However, THg concentration correlated strongly with ecotype and was reflected in the THg concentrations detected in available food sources in each ecotype. The highest concentration of THg was found in ecotypes where foxes depended on marine vertebrates for food. Exclusively inland ecotypes had low THg concentrations. The results suggest that absolute exposure to heavy metals may be less important than the feeding ecology and feeding opportunities of top predators such as arctic foxes which may in turn influence population health and stability. A higher risk to wildlife of heavy metal exposure correlates with feeding strategies that rely primarily on a marine based diet. PMID:23671561

Krone, Oliver; Stefanski, Volker; Wibbelt, Gudrun; Unnsteinsdóttir, Ester Rut; Hersteinsson, Páll; Schares, Gereon; Doronina, Lilia; Goltsman, Mikhail; Greenwood, Alex D.

2013-01-01

54

Correlates between feeding ecology and mercury levels in historical and modern arctic foxes (Vulpes lagopus).  

PubMed

Changes in concentration of pollutants and pathogen distribution can vary among ecotypes (e.g. marine versus terrestrial food resources). This may have important implications for the animals that reside within them. We examined 1) canid pathogen presence in an endangered arctic fox (Vulpes lagopus) population and 2) relative total mercury (THg) level as a function of ecotype ('coastal' or 'inland') for arctic foxes to test whether the presence of pathogens or heavy metal concentration correlate with population health. The Bering Sea populations on Bering and Mednyi Islands were compared to Icelandic arctic fox populations with respect to inland and coastal ecotypes. Serological and DNA based pathogen screening techniques were used to examine arctic foxes for pathogens. THg was measured by atomic absorption spectrometry from hair samples of historical and modern collected arctic foxes and samples from their prey species (hair and internal organs). Presence of pathogens did not correlate with population decline from Mednyi Island. However, THg concentration correlated strongly with ecotype and was reflected in the THg concentrations detected in available food sources in each ecotype. The highest concentration of THg was found in ecotypes where foxes depended on marine vertebrates for food. Exclusively inland ecotypes had low THg concentrations. The results suggest that absolute exposure to heavy metals may be less important than the feeding ecology and feeding opportunities of top predators such as arctic foxes which may in turn influence population health and stability. A higher risk to wildlife of heavy metal exposure correlates with feeding strategies that rely primarily on a marine based diet. PMID:23671561

Bocharova, Natalia; Treu, Gabriele; Czirják, Gábor Árpád; Krone, Oliver; Stefanski, Volker; Wibbelt, Gudrun; Unnsteinsdóttir, Ester Rut; Hersteinsson, Páll; Schares, Gereon; Doronina, Lilia; Goltsman, Mikhail; Greenwood, Alex D

2013-01-01

55

Chronic dietary exposure to environmental organochlorine contaminants induces thyroid gland lesions in Arctic foxes (Vulpes lagopus).  

PubMed

The impact of dietary organochlorine (OC) exposure on thyroid gland pathology was studied in farmed male Arctic foxes (Vulpes lagopus). The exposed group (n=16) was fed a diet based on wild minke whale (Balaenoptera acutorostrata) blubber as a main fat source in order to mimic the exposure to OC cocktails in the Artic environment. This resulted in an exposure of approximately 17 microg Sigma OC/kg day and a Sigma OC residue adipose tissue and liver concentration of 1700 and 4470 ng/gl.w., respectively, after 16 months of exposure. Control foxes (n=13) were fed a diet with pork (Sus scrofa) fat as a main fat source containing significantly lower OC concentrations. The food composition fed to the control and exposed group was standardized for nutrient contents. Four OC-related histopathological changes were found: (1) flat-epithelial-cell true thyroid cysts (TC) characterized by neutral content; (2) remnants of simple squamous epithelial-cell embryonic ducts containing neutral debris (EDN); (3) remnants of stratified squamous epithelial-cell embryonic ducts containing acid mucins often accompanied with debris of leukocyte inflammatory nature (EDM) and (4) disseminated thyroid C-cell hyperplasia (HPC). Of these, the prevalence of TC, EDN and HPC was significantly highest in the exposed group (chi(2) test: all p<0.04). The study shows that the OC mixture in minke whale blubber may cause development of thyroid gland cysts, C-cell hyperplasia and increase the prevalence of cystic remnants of embryonic ducts. The mechanism causing these effects could include endocrine disruption of the hypothalamus-pituitary-thyroid (HPT) axis, a disturbance of the calcium homeostasis/metabolism or energy metabolism or immune suppression. Because concentrations of OCs are higher in wild Arctic foxes, it is likely that these animals could suffer from similar OC-induced thyroid gland pathological and functional changes. PMID:19464679

Sonne, Christian; Wolkers, Hans; Leifsson, Pall S; Iburg, Tine; Jenssen, Bjørn Munro; Fuglei, Eva; Ahlstrøm, Oystein; Dietz, Rune; Kirkegaard, Maja; Muir, Derek C G; Jørgensen, Even H

2009-08-01

56

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

57

Direct high-resolution genotyping of Toxoplasma gondii in arctic foxes ( Vulpes lagopus) in the remote arctic Svalbard archipelago reveals widespread clonal Type II lineage  

Microsoft Academic Search

Characterization of Toxoplasma gondii genotypes in hosts living in remote, isolated regions is important for elucidating the population structure and transmission mode of this parasite. Herein, we report the results of direct genotyping of T. gondii in brain tissue of arctic foxes (Vulpes lagopus) from the remote, virtually cat-free, high arctic islands of Svalbard. DNA extracts from brains of 167

Kristin Wear Prestrud; Kjetil Åsbakk; Torill Mørk; Eva Fuglei; Morten Tryland; Chunlei Su

2008-01-01

58

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

PubMed

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 its metabolites from a 300 mg sample of red grouse liver. This method could be used to improve the efficacy of medicated grit treatment by allowing the identification of conditions and application methods that optimize the uptake of FBZ. With the necessary modifications, our method will also be applicable to other wildlife species where self-medication is used for parasite control. PMID:21236579

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

2011-05-11

59

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

E-print Network

ricinus on red grouse Lagopus lagopus scoticus chicks to temporal (year), spatial (altitude and location linear mixed model, Ixodes ricinus, Lagopus lagopus scoticus, Poisson- lognormal distribution, variance. ricinus on chicks of red grouse Lagopus lagopus scoticus as an example. The Poisson distribution

Lambin, Xavier

60

vol. 174, no. 3 the american naturalist september 2009 Fitting Models of Multiple Hypotheses to Partial Population  

E-print Network

fluctuations (cycles) in red grouse (Lagopus lagopus scoticus). The first involves interaction, cyclic population dy- namics, Lagopus lagopus scoticus, state-space modeling, Trichostron- gylus tenuis, there is a single species, the red grouse (Lagopus lagopus scoticus), whose population cycles can be driven

Buckland, Steve

61

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

62

Determination of sperm acrosin activity in the arctic fox (Alopex lagopus L.)--using method developed for human spermatozoa.  

PubMed

The aim of the study was to adapt a method to determine acrosin activity of human spermatozoa to arctic fox (Alopex lagopus L.) spermatozoa. We modified this method by reducing sperm count per sample from 1 divided by 10 x 10(6) to 25 divided by 200 x 10(3), incubation time from 180 minutes to 60 minutes, and Triton X-100 concentration in the reaction mixture from 0.01% to 0.005% per 100 cm3. It has also confirmed that arctic fox seminal plasma is rich in proteinases and their inhibitors. To completely abolish the inhibitory effect of seminal plasma on acrosin activity it is recommended to wash the spermatozoa four times. Benzamidine served an inhibitor of acrosin activity. PMID:23390774

Stasiak, K; Janicki, B; Glogowski, J

2012-01-01

63

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

64

Effect of age and breeding season on sperm acrosin activity in the arctic fox (Alopex lagopus L.).  

PubMed

The objective of this study was to determine the effect of age and reproductive season on selected properties of semen from the arctic fox, Aloper lagopus L. The experiment used 40 ejaculates collected manually from 6 animals (3 foxes aged one year and 3 foxes older than three years). Statistically less semen (0.39 cm3) was collected from the young compared to the older animals, and the ejaculates obtained were characterized by higher concentration of spermatozoa (195.04 x 106/cm3). In turn, sperm acrosomal extracts from the older animals contained statistically more acrosin (6,4 mU/106 spermatozoa). In the sperm acrosomal extracts prepared during the first semen sampling, the mean acrosin activity did not exceed 2.3 mU/million spermatozoa. At subsequent semen sampling dates, the activity of the analysed enzyme increased to reach 7.72 mU/million spermatozoa. In the extracts obtained from the semen collected at the end of the breeding season of arctic foxes, the acrosin activity again reached a value obtained at the beginning of the season. PMID:24724488

Stasiak, K; Janicki, B

2014-01-01

65

Muscular sarcocystosis in two arctic foxes (Vulpes lagopus) due to Sarcocystis arctica n. sp.: sarcocyst morphology, molecular characteristics and phylogeny.  

PubMed

The arctic fox (Vulpes lagopus) is a critically endangered species in Norway, and therefore, the small population is closely monitored, and most foxes found dead are subjected to necropsy. In two deceased foxes, thin-walled muscular sarcocysts were first detected in histological sections, and numerous sarcocysts were later found in frozen and thawed muscle samples from Fox 1. These sarcocysts measured 1-12 × 0.1-0.25 mm and had closely spaced, short, knob-like protrusions, giving the cysts a serrated outline. Genomic DNA was extracted from eight isolated sarcocysts (Fox 1) and two muscle samples (Fox 2) and subjected to polymerase chain reaction amplification at four loci: the nuclear 18S and 28S ribosomal RNA genes and internal transcribed spacer 1 region and the mitochondrial cytochrome c oxidase subunit 1 gene (cox1). Both foxes were infected by the same Sarcocystis sp., which displayed little or no genetic variation at the three nuclear loci (99.9-100% identity) and slightly more variation at cox1 (99.4-100% identity). Sequence comparisons and phylogenetic analyses revealed that this species was distinct from other named Sarcocystis spp. but was closely related to various species using avian intermediate hosts and possibly identical to an unnamed species reported from two American dogs. The species described from the two arctic foxes was named Sarcocystis arctica n. sp. PMID:24297693

Gjerde, Bjørn; Schulze, Johan

2014-03-01

66

Impact of historical founder effects and a recent bottleneck on MHC variability in Commander Arctic foxes (Vulpes lagopus).  

PubMed

Populations of Arctic foxes (Vulpes lagopus) have been isolated on two of the Commander Islands (Bering and Mednyi) from the circumpolar distributed mainland population since the Pleistocene. In 1970-1980, an epizootic outbreak of mange caused a severe population decline on Mednyi Island. Genes of the major histocompatibility complex (MHC) play a primary role in infectious disease resistance. The main objectives of our study were to compare contemporary variation of MHC class II in mainland and island Arctic foxes, and to document the effects of the isolation and the recent bottleneck on MHC polymorphism by analyzing samples from historical and contemporary Arctic foxes. In 184 individuals, we found 25 unique MHC class II DRB and DQB alleles, and identified evidence of balancing selection maintaining allelic lineages over time at both loci. Twenty different MHC alleles were observed in mainland foxes and eight in Bering Island foxes. The historical Mednyi population contained five alleles and all contemporary individuals were monomorphic at both DRB and DQB. Our data indicate that despite positive and diversifying selection leading to elevated rates of amino acid replacement in functionally important antigen-binding sites, below a certain population size, balancing selection may not be strong enough to maintain genetic diversity in functionally important genes. This may have important fitness consequences and might explain the high pathogen susceptibility in some island populations. This is the first study that compares MHC diversity before and after a bottleneck in a wild canid population using DNA from museum samples. PMID:22408734

Ploshnitsa, Anna I; Goltsman, Mikhail E; Macdonald, David W; Kennedy, Lorna J; Sommer, Simone

2012-01-01

67

Seasonal emaciation causes tissue redistribution and an increased potential for toxicity of lipophilic pollutants in farmed arctic fox (Vulpes lagopus).  

PubMed

Many Arctic animals carry high body burdens of organochlorine contaminants (OCs) as a result of long-range transport of persistent pollutants. It has been shown that seasonal mobilization of body fat in these species results in increased blood concentration of OCs. The authors investigated OC assimilation, tissue distribution, and biotransformation in farmed Arctic fox (Vulpes lagopus) continuously fed a diet containing contaminated minke whale blubber or lard (control) from 8 wk of age in August 2003, until sampling when they were at their fattest (in November 2004) and leanest (in June 2005). Markedly higher tissue (liver, adrenals, brain, and blood) OC levels were found in June than in November despite low exposure to OCs during emaciation, suggesting that OCs had been redistributed from adipose tissues to vital organs. There were no differences in the activities of hepatic biotransforming enzymes between exposed fat and control fat foxes, except for 16?-hydroxylation, which was higher in exposed fat foxes. In emaciated foxes, ethoxyresorufin activity was higher in exposed than in control foxes, indicating an enhanced potential for toxicity of OCs with emaciation. Lower activities of 6?- and 2?-hydroxylation were found in lean than in fat foxes, irrespective of OC treatment. The results show that emaciation increase the toxic potential of accumulated OCs and emphasize that body adiposity must be considered when time-trend analyses, risk assessments, and effect studies are designed. Environ Toxicol Chem 2013;32:1784-1792. © 2013 SETAC. PMID:23606128

Helgason, Lisa B; Wolkers, Hans; Fuglei, Eva; Ahlstrøm, Oystein; Muir, Derek; Jørgensen, Even H

2013-08-01

68

Effects of dietary fat levels on nutrient digestibility and production performance of growing-furring blue foxes (Alopex lagopus).  

PubMed

The objective of this study was to determine whether nutrient digestibility and production performance of growing-furring blue foxes (Alopex lagopus) are affected by different dietary fat levels. Sixty-four young animals were randomly assigned to four groups (A, B, C, D) provided with diets containing approximately 12%, 26%, 40%, 54% fat in the dry matter respectively. When dietary fat level was increased, the apparent digestibility of main nutrients except for crude carbohydrates, and gross energy were improved (p < 0.0001). The amount of nitrogen excreted was reduced and the biological value of protein was enhanced (p < 0.0001). Over the experimental phase, the efficiency of metabolizable energy (ME) used for gain in group B (26% fat content) was higher than that in other groups. When diets with 12-26% fat content were fed, there was an increasing tendency in skin size. But it had negative effects on skin size and fur quality when the amount of fat content was over 40%. In conclusion, the experiment showed that dietary fat could significantly improve some nutrient utilization and significantly reduce feed/gain ratio as a main energy source. The most preferable fur quality and efficiency of ME used for gain were obtained when diet contained 26% fat level in growing-furring period. PMID:21740467

Geng, Y Y; Yang, F H; Xing, X M; Gao, X H

2012-08-01

69

Impact of historical founder effects and a recent bottleneck on MHC variability in Commander Arctic foxes (Vulpes lagopus)  

PubMed Central

Populations of Arctic foxes (Vulpes lagopus) have been isolated on two of the Commander Islands (Bering and Mednyi) from the circumpolar distributed mainland population since the Pleistocene. In 1970–1980, an epizootic outbreak of mange caused a severe population decline on Mednyi Island. Genes of the major histocompatibility complex (MHC) play a primary role in infectious disease resistance. The main objectives of our study were to compare contemporary variation of MHC class II in mainland and island Arctic foxes, and to document the effects of the isolation and the recent bottleneck on MHC polymorphism by analyzing samples from historical and contemporary Arctic foxes. In 184 individuals, we found 25 unique MHC class II DRB and DQB alleles, and identified evidence of balancing selection maintaining allelic lineages over time at both loci. Twenty different MHC alleles were observed in mainland foxes and eight in Bering Island foxes. The historical Mednyi population contained five alleles and all contemporary individuals were monomorphic at both DRB and DQB. Our data indicate that despite positive and diversifying selection leading to elevated rates of amino acid replacement in functionally important antigen-binding sites, below a certain population size, balancing selection may not be strong enough to maintain genetic diversity in functionally important genes. This may have important fitness consequences and might explain the high pathogen susceptibility in some island populations. This is the first study that compares MHC diversity before and after a bottleneck in a wild canid population using DNA from museum samples. PMID:22408734

Ploshnitsa, Anna I; Goltsman, Mikhail E; Macdonald, David W; Kennedy, Lorna J; Sommer, Simone

2012-01-01

70

ORIGINAL ARTICLE Carotenoid-based colouration and ultraviolet reflectance  

E-print Network

is not visible to humans but is likely to be visible to grouse. In male red grouse Lagopus lagopus scoticus, we the perception of caroten- oid-based signals of quality. Keywords Carotenoid . Colour. Red grouse Lagopus lagopus

Bortolotti, Gary R.

71

Vitamin C deficiency in growing willow ptarmigan (Lagopus lagopus lagopus).  

PubMed

Willow ptarmigan chicks raised on a diet containing 265 mg ascorbic acid/kg develop scury-like symptoms and die by 4 weeks of age. If blueberry plants are given as an ad libitum supplement to this diet, the malady is prevented. We have described the clinical, pathological and histological changes which accompany this malnutrition and conclude that they are in accord with the description of scurvy in guinea pig and man. Biochemical determination of ascorbic acid synthesis in the kidney of ptarmigan chicks indicated a rate of synthesis five times that found in livers of growing white rats. Blueberry plants and many other plants found in the natural diet of ptarmigan chicks contain 2,000 to 5,000 mg ascorbic acid/kg dry weight. Feeding experiments showed that the pathological signs were avoided and that already afflicted chicks recovered if the vitamin C content of the diet was raised to 750 mg/kg dry weight of food. Since the food intake of the chicks was 5 to 8 g/day the daily requirement of external vitamin C is about 150 mg/kg body weight. To our knowledge this is the first example of an animal which, while producing vitamin C itself, requires substantial amounts of external vitamin C to survive. PMID:512712

Hanssen, I; Grav, H J; Steen, J B; Lysnes, H

1979-12-01

72

Two cysteine substitutions in the MC1R generate the blue variant of the Arctic fox (Alopex lagopus) and prevent expression of the white winter coat.  

PubMed

We have characterized two mutations in the MC1R gene of the blue variant of the arctic fox (Alopex lagopus) that both incorporate a novel cysteine residue into the receptor. A family study in farmed arctic foxes verified that the dominant expression of the blue color phenotype cosegregates completely with the allele harboring these two mutations. Additionally to the altered pigment synthesis, the blue fox allele suppresses the seasonal change in coat color found in the native arctic fox. Consequently, these findings suggest that the MC1R/agouti regulatory system is involved in the seasonal changes of coat color found in arctic fox. PMID:15982782

Våge, Dag Inge; Fuglei, Eva; Snipstad, Kristin; Beheim, Janne; Landsem, Veslemøy Malm; Klungland, Helge

2005-10-01

73

Glomerular lipidosis accompanied by renal tubular oxalosis in wild and laboratory-reared Japanese rock ptarmigans (Lagopus mutus japonicus).  

PubMed

Glomerular lipidosis is a disease characterized by lipid accumulation in mesangial cells but that has not been fully investigated in avian species. We examined four wild and two laboratory-reared Japanese rock ptarmigans (Lagopus mutus japonicus)--an endangered avian species--presenting vacuolar deposits in the glomeruli. All cases had vacuolar deposits in the glomeruli. In the wild cases, fewer than 30% of all glomeruli were affected, compared with more than 90% in the laboratory-reared cases. In the wild cases, most deposits were mild and restricted to the mesangial areas of glomeruli. In the laboratory-reared cases, nearly all of the deposits covered entire glomeruli. Electron microscopy of mild deposits revealed vacuoles in the cytoplasm of mesangial cells. These vacuoles were positive for Sudan III, Sudan black B, oil red O, Nile blue, periodic acid-Schiff, Schultz test, and digitonin stain and were negative for performaric acid-Schiff stains. Based on these results, we diagnosed the glomerular lesion as glomerular lipidosis caused by uptake of low-density lipoprotein in mesangial cells. Except for one wild case, all cases exhibited renal tubular oxalosis. The severity of tubular oxalosis tended to be related to the severity of glomerular lipidosis: In cases of mild glomerular lipidosis, tubular oxalosis was also mild or absent. We therefore diagnosed the primary lesion as glomerular lipidosis accompanied by tubular oxalosis. The four wild cases came from different zones and therefore had no opportunities to interbreed and no common relatives. We believe these data support the hypothesis that glomerular lipidosis is a disease of the general population ofJapanese rock ptarmigans. This is the first report of glomerular lipidosis accompanied by renal tubular oxalosis in an avian species. PMID:22312998

Murai, Atsuko; Murakami, Mami; Sakai, Hiroki; Shimizu, Hiroaki; Murata, Koichi; Yanai, Tokuma

2011-12-01

74

Use of biochemical markers to evaluate the quality of fresh and cryopreserved semen from the arctic fox (Vulpes lagopus).  

PubMed

The aim of this study was to use biochemical markers to evaluate the quality of fresh and cryopreserved semen from the arctic fox (Vulpes lagopus). Twenty-three manually collected ejaculates were analysed for the main indicators of semen quality (sperm concentration and ejaculate volume). Sperm motility and percentage of morphologically normal and abnormal spermatozoa were determined according to the stage of cryopreservation (fresh--measurement A; equilibrated--measurement B; frozen/thawed--measurement C). Furthermore, the seminal plasma and supernatants were analysed after equilibration and freeze/thawing for the activity of the enzymes alkaline phosphatase (ALP), acid phosphatase (AcP), lactate dehydrogenase (LDH) and aspartate aminotransferase (AspAT), and for the activity of acrosin inhibitors (AP). The mean concentration of sperm was 625.1 million/cm3, and ejaculate volume averaged 1.6 cm3. Seminal plasma was characterized by the highest activity of alkaline phosphatase (3.43 x 10(3) U/l) and lowest activity of acrosin inhibitors (4.55 x 10(3) U/l). After equilibration, the supernatants showed the highest activity of acid phosphatase (94.9 U/l) and after freeze-thawing, they showed a high activity of lactate dehydrogenase (535.8 U/l) and aspartate aminotransferase (577.1 U/l), which indicates that these proteins had leaked from spermatozoa into the extracellular medium during the biotechnique of semen cryopreservation. In addition, several significant relationships were found between some indicators of semen quality and plasma and/or supernatant enzyme activity. PMID:25286649

Stasiak, K; Glogowski, J; Demianowicz, W; Kowalski, R; Nowak-Tkaczyk, A; Janicki, B

2014-01-01

75

Ileal and total tract nutrient digestibility in blue foxes (Alopex lagopus) fed extruded diets containing different protein sources.  

PubMed

This study compared apparent ileal and total tract digestibility of macronutrients and amino acids in blue foxes (Alopex lagopus) fed dry extruded diets. The control diet contained fish meal as the main protein source, while in the other diets 50% of the fish meal protein was replaced by not de-hulled solvent-extracted soybean meal, meat meal or bacterial protein meal. Ileal digestibility was obtained with animals modified with ileorectal anastomosis (IRA method). There were no significant differences in the average digestibility of CP, Lys, Trp, Val, Ala or Glu between IRA modified and intact animals. Average ileal digestibilities of His, Thr, Asp, Cys, Gly, Hyp, Pro, Ser, starch and total carbohydrates (CHO) were significantly lower compared with total tract values. Average ileal digestibility of Arg, Ile, Leu, Met, Phe, Tyr and crude fat was significantly higher than total tract digestibility. Digestibility measured in IRA modified animals showed less variability compared with values from intact animals. There were significant differences among diets in ileal as well as total tract digestibility of orude protein, most amino acids, starch and CHO, and in ileal digestibility of crude fat. Ileal crude protein digestibility of the diets ranged from 81.0-86.4% and total tract digestibility from 82.5-86.4%. Ileal amino acid digestibilities ranged from 70.1 (Asp) to 93.3% (Arg) and total tract values ranged from 72.8 (Cys) to 92.2% (Arg). Both ileal and total tract digestibilities of crude protein and most amino acids were significantly lower for diets containing meat meal or bacterial protein meal compared with the control fish meal-based diet and the diet with soybean meal. Although ileal digestibility may be more accurate than total tract digestibility in estimating the protein and amino acid supply in blue foxes, total tract digestibility may be acceptable because of numerically small differences between ileal and total tract digestibilities for protein and most amino acids. It was further concluded that ileal digestibilities of starch and CHO in the blue fox are lower than corresponding total tract digestibilities. PMID:15889653

Vhile, Stine G; Skrede, Anders; Ahlstrøm, Oystein; Szymeczko, Roman; Hove, Knut

2005-02-01

76

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

77

Molecular Ecology (2008) 17, 25442551 doi: 10.1111/j.1365-294X.2008.03778.x 2008 The Authors  

E-print Network

structure through a population cycle in a territorial bird, the red grouse Lagopus lagopus scoticus STUART B grouse (Lagopus lagopus scoticus) undergo regular multiannual cycles in abundance. The `kinship for population genetics. Keywords: kin selection, kin structure, Lagopus, population cycles, red grouse Received

Nottingham, University of

2008-01-01

78

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

79

Fox encephalitozoonosis: isolation of the agent from an outbreak in farmed blue foxes (Alopex lagopus) in Finland and some hitherto unreported pathologic lesions.  

PubMed

The farmed blue fox (Alopex lagopus) is particularly susceptible to congenital infections of the microsporidian species Encephalitozoon cuniculi. This report is based on an outbreak of the disease in Finland with high mortality. Five pups (four males and one female) with prolonged disease were examined. The pups had moderate pathological alterations in the kidneys and mild lesions were found in the brains, hearts, salivary and prostatic glands. Diagnosis of E. cuniculi infection was made from serological tests (ELISA, CIA, IFAT), and by in vitro isolation of the parasite from the brain of all five pups investigated. The identity was confirmed by molecular means as E. cuniculi strain II ('mouse strain'). Novel histopathological lesions not described as yet in fox encephalitozoonosis are presented. These include cerebral infarction and necrotizing inflammation of the renal pelvis. The sources and mechanisms of spreading of E. cuniculi to blue foxes are discussed. PMID:12449250

Akerstedt, J; Nordstoga, K; Mathis, A; Smeds, E; Deplazes, P

2002-10-01

80

Dietary contaminant exposure affects plasma testosterone, but not thyroid hormones, vitamin A, and vitamin E, in male juvenile arctic foxes (Vulpes lagopus).  

PubMed

Levels of persistent organic pollutants (POP), such as polychlorinated biphenyls (PCB), are high in many Arctic top predators, including the Arctic fox (Vulpes lagopus). The aim of this study was to examine possible endocrine-disruptive effects of dietary POP exposure in male juvenile Arctic foxes in a controlled exposure experiment. The study was conducted using domesticated farmed blue foxes (Vulpes lagopus) as a model species. Two groups of newly weaned male foxes received a diet supplemented with either minke whale (Baleneoptera acutorostrata) blubber that was naturally contaminated with POP (exposed group, n?=?5 or 21), or pork (Sus scrofa) fat (control group, n?=?5 or 21). When the foxes were 6 mo old and had received the 2 diets for approximately 4 mo (147 d), effects of the dietary exposure to POP on plasma concentrations of testosterone (T), thyroid hormones (TH), thyroid-stimulating hormone (TSH), retinol (vitamin A), and tocopherol (viramin E) were examined. At sampling, the total body concentrations of 104 PCB congeners were 0.1 ± 0.03 ?g/g lipid weight (l.w.; n?=?5 [mean ± standard deviation]) and 1.5 ± 0.17 ?g/g l.w. (n?=?5) in the control and exposed groups, respectively. Plasma testosterone concentrations in the exposed male foxes were significantly lower than in the control males, being approximately 25% of that in the exposed foxes. There were no between-treatment differences for TH, TSH, retinol, or tocopherol. The results suggest that the high POP levels experienced by costal populations of Arctic foxes, such as in Svalbard and Iceland, may result in delayed masculine maturation during adolescence. Sex hormone disruption during puberty may thus have lifetime consequences on all aspects of reproductive function in adult male foxes. PMID:23030655

Hallanger, Ingeborg G; Jørgensen, Even H; Fuglei, Eva; Ahlstrøm, Øystein; Muir, Derek C G; Jenssen, Bjørn Munro

2012-01-01

81

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)  

Microsoft Academic Search

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

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

2004-01-01

82

Seasonal changes in spermatogenesis in the blue fox (Alopex lagopus), quantified by DNA flow cytometry and measurement of soluble Mn2+ -dependent adenylate cyclase activity.  

PubMed

The testes of the blue fox (Alopex lagopus) showed marked seasonal variations in size. Testicular weight and volume increased rapidly during January and February to reach maximal values by the beginning of the breeding season (approximately 15 March). During May and June the weights and volumes of the testes declined gradually to the quiescent state which lasted from July until October. Quantitation by DNA flow cytometry of the seasonal changes in the relative numbers of haploid (1C), diploid (2C) and tetraploid (4C) cell numbers in the testis showed that the increase in testis size from December to February was associated with a rapid expansion of the haploid cell compartment as spermatogenesis resumed. In addition, an increase in number of more mature cell types within the haploid cell population was observed over a 2-month period before the breeding season. The decline in testicular size from the middle of April until October was associated with a reduction in both the absolute and relative sizes of the haploid and tetraploid cell populations and a concomitant increase in the relative numbers of diploid cells. Measurements of the activity of the soluble Mn2+ -dependent adenylate cyclase revealed seasonal variations that closely paralleled those of the haploid cell population, indicating that, as in other species, the enzyme may be associated with maturing germ cells. PMID:6512769

Smith, A J; Clausen, O P; Kirkhus, B; Jahnsen, T; Møller, O M; Hansson, V

1984-11-01

83

The red fox (Vulpes vulpes) and the arctic fox (Vulpes lagopus) are definitive hosts of Sarcocystis alces and Sarcocystis hjorti from moose (Alces alces).  

PubMed

The aim of this study was to determine whether foxes might act as definitive hosts of Sarcocystis alces in moose. In 2 experiments, 6 silver foxes (Vulpes vulpes) and 6 blue foxes (Vulpes lagopus) were fed muscle tissue from moose containing numerous sarcocysts of S. alces, and euthanazed 7-28 days post-infection (p.i.). Intestinal mucosal scrapings and faecal samples were screened microscopically for Sarcocystis oocysts/sporocysts, which were identified to species by means of species-specific primers and sequence analysis targeting the ssu rRNA gene. All foxes in both experiments became infected with Sarcocystis; the oocysts were fully sporulated by 14 days p.i., containing sporocysts measuring 14-15 x 10 microm. Molecular identification revealed that the oocysts/sporocysts belonged to 2 species, S. alces and Sarcocystis hjorti, although sarcocysts of S. hjorti were only identified in moose subsequent to the infection of foxes. In the first experiment, all 8 foxes also became infected with a Hammondia sp. derived from moose, shedding unsporulated, subspherical oocysts, measuring 10-12 microm in diameter, from 6-7 days p.i. onwards. The study proved that canids (the red fox and arctic fox) are definitive hosts for S. alces and S. hjorti, as had been inferred from the phylogenetic position of these species. PMID:20500918

Dahlgren, Stina S; Gjerde, Bjørn

2010-09-01

84

The metabolic cost of incline locomotion in the Svalbard rock ptarmigan (Lagopus muta hyperborea): the effects of incline grade and seasonal fluctuations in body mass.  

PubMed

In a terrestrial environment animals must locomote over varying terrain; despite this, the majority of studies of animal locomotion focus on level locomotion. The influence moving up an inclined surface has on the metabolic cost of locomotion and the efficiency with which animals perform positive work against gravity is still not well understood. Generally speaking, existing data sets lack consistency in the use of grades, further compounded by differences between species in terms of morphology and locomotor gait. Here we investigated the metabolic cost of locomotion using respirometry in the Svalbard ptarmigan (Lagopus muta hyperborea). The Svalbard ptarmigan provides a unique opportunity to investigate the cost of incline locomotion as it undergoes a seasonal fluctuation in body mass, which doubles in winter, meaning the requirement for positive mechanical work also fluctuates with season. We demonstrate that at the same degree of incline, the cost of lifting 1 kg by 1 vertical metre remains relatively constant between seasons despite the large differences in body mass from summer to winter. These findings are consistent with the notion that positive mechanical work alone dictates the cost of lifting above a certain body mass. However, our data indicate that this cost may vary according to the degree of incline and gait. PMID:23264484

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

2013-04-15

85

The effects of season and sex upon the morphology and material properties of keratin in the Svalbard rock ptarmigan (Lagopus muta hyperborea).  

PubMed

The material properties and morphologies of the modified integumentary organs of birds (the keratinous bills, claws and feathers) have evolved to withstand the variety of mechanical stresses imposed by their interaction with the environment. These stresses are likely to vary temporally in seasonal environments and may also differ between the sexes as a result of behavioural dimorphism. Here we investigate the morphology and material properties of the claws of male and female Svalbard ptarmigan (Lagopus muta hyperborea) during the summer and winter using nanoindentation. Despite differences in locomotor demands between the sexes and pronounced seasonal differences in environmental conditions, like ground substrate, ambient temperature and day length, there was no significant difference in Young?s modulus or hardness between the seasons for each sex. However, when comparing males and females, female claws were significantly harder than those of males and both sexes had significantly wider claws during winter. We propose that wider claws may follow winter claw moulting as the claws are regrown and form an important part of the ptarmigan?s snowshoe-like foot that is an adaptation to locomotion on snow. Future work focusing on growth rates and more broad measures of material properties in both captive and wild birds is required to determine the extent of seasonal and sex differences in the material properties of their keratinous structures. PMID:25086983

Lees, John J; Folkow, Lars P; Nudds, Robert L; Codd, Jonathan R

2014-08-01

86

2000 The Society for the Study of Evolution. All rights reserved. Evolution, 54(1), 2000, pp. 279289  

E-print Network

. 279­289 MATRILINEAL GENETIC STRUCTURE AND FEMALE-MEDIATED GENE FLOW IN RED GROUSE (LAGOPUS LAGOPUS among 14 populations of red grouse (Lagopus lagopus scoticus) in northeastern Scotland. Ten haplotypes we observe are meaningful. Key words. Gene flow, grouse, Lagopus, mitochondrial DNA, philopatry

Nottingham, University of

87

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

88

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

89

Vitamin C Deíiciencyin Growing Willow Ptarmigan1 (Lagopus lagopus lagopus)  

Microsoft Academic Search

Willow ptarmigan chicks raised on a diet containing 265 mg ascorbic acid\\/kg develop scurvy-like symptoms and die by 4 weeks of age. If blueberry plants are given as an ad libitum supplement to this diet, the malady is prevented. We have described the clinical, pathological and histológica!changes which accompany this malnutrition and conclude that they are in accord with the

HANS J. GRAY; JOHAN B. STEEN

90

Cadmium concentrations in tissues of willow ptarmigan ( Lagopus lagopus) and rock ptarmigan ( Lagopus muta) in Nunavik, Northern Québec  

Microsoft Academic Search

Willow and rock ptarmigan were obtained from Northern Québec. Willow ptarmigan were found to have mean cadmium concentrations of 179.7?g\\/g (dw) in the kidneys and 25.8?g\\/g (dw) in the liver; these levels were three times higher than those found in the rock ptarmigan. The cadmium levels in the ptarmigan were below the threshold above which adverse effects can be observed

Jean Rodrigue; Louise Champoux; Daniel Leclair; Jean-François Duchesne

2007-01-01

91

The effect of recreational homes on willow ptarmigan ( Lagopus lagopus ) in a mountain area of Norway  

Microsoft Academic Search

The increasing development of recreational resorts and second homes in mountain regions worldwide require substantial infrastructure,\\u000a and have large impact on habitats and ecosystems. We hypothesized that developed areas would attract predators and lead to\\u000a higher predation on willow ptarmigan and lower their abundance. In a 500-km2 study area in south-central Norway, we sampled the density of territorial cocks in

Ole-Gunnar Støen; Per Wegge; Stian Heid; Olav Hjeljord; Christian Nellemann

2010-01-01

92

A multilocus assay reveals high nucleotide diversity and limited differentiation among Scandinavian willow grouse (Lagopus lagopus)  

Microsoft Academic Search

BACKGROUND: There is so far very little data on autosomal nucleotide diversity in birds, except for data from the domesticated chicken and some passerines species. Estimates of nucleotide diversity reported so far in birds have been high (~10-3) and a likely explanation for this is the generally higher effective population sizes compared to mammals. In this study, the level of

Maria Quintela; Jacob Höglund

2008-01-01

93

CHARACTERISTICS OF TERRITORIAL AND MATING CALLS IN WILLOW PTARMIGAN LAGOPUS L. LAGOPUS  

Microsoft Academic Search

During territorial behaviour and pair formation willow ptarmigan cocks and hens use several different calls. Cocks use mainly a “flight call”, a “ground call” and three different “threat calls”. Hens give similar calls to cocks. It is suggested that the structure of the calls is well adapted to (1) transmit their possible information content over long distances, and (2) make

ROAR JOHNSEN; YNGVE ESPMARK; HANS CHR. PEDERSEN; JOHAN B. STEEN

1991-01-01

94

Metallothionein levels in willow ptarmigan ( Lagopus lagopus ) populations with different natural loads of cadmium  

Microsoft Academic Search

The tissues of willow ptarmigan in some Norwegian mountain areas contain elevated concentrations of cadmium (Cd). It is not\\u000a known whether such high Cd levels would have negative impacts in otherwise healthy populations of this species. The aim of\\u000a the current study was to clarify relationships between hepatic and renal metallothionein (MT) and Cd concentrations in willow\\u000a ptarmigan to assess

Hans C. Pedersen; Ketil Hylland

2007-01-01

95

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.

96

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

97

Supplement 23, Part 2, Parasite-Subject Catalogue, Parasites: Protozoa  

E-print Network

-190 Corvus corone C. frugilegus C. monedula Fringilla coelebs Garrulus glandarius Muscicapa striata Parus caeruleus Sturnus vulgaria Turdus ericetorum T. merula Strix aluco Gall?nula chloropus Columba palumbus Lagopus scoticus all from Britain...

Zidar, Judith A.; Shaw, Judith H.; Hanfman, Deborah T.; Kirby, Margie D.; Rayburn, Jane D.; Edwards, Shirley J.; Hood, Martha W.

1982-01-01

98

Gnawing bones as enrichment for farmed blue foxes ( Vulpes lagopus).  

PubMed

According to present acts and regulations, farmed foxes shall have a gnawing or other enrichment object in their cages. However, research on the welfare effects of gnawing objects has been scarce. We assessed physiology and health, that is weight development, urinary cortisol-creatinine ratio, serum cortisol level after adrenocorticotropic hormone administration, internal organ masses and incidence of gastric ulcerations as well as dental and overall oral health, in pair-housed juvenile blue foxes that were housed either with or without a possibility to interact with bones (cattle femur) during their growing season (July to December). The results show that the physiological effects of the possibility to interact with bones were either non-significant or suggested that competition for bones may jeopardize the welfare of subordinate individuals. However, the results clearly show that gnawing bones are beneficial for the dental health of farmed foxes. PMID:22444268

Ahola, L; Turunen, A; Mononen, J; Koistinen, T

2010-06-01

99

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

100

Comparative nutrient digestibility of arctic foxes (Alopex lagopus) on Svalbard and farm-raised blue foxes (Alopex lagopus).  

PubMed

Arctic foxes from Svalbard (n=4) and farmed blue foxes (n=4) was used in a digestibility experiment with a high-carbohydrate feed to add more information to the nutritional physiology of the arctic fox, and to compare its digestive capacity with that of the farmed blue fox. The arctic fox has a diet containing mainly protein and fat from mammals and birds, while farmed blue foxes have been exposed to an omnivorous dietary regime for more than 80 generations. The experiment showed in general no difference in digestive capacity for protein and fat between the foxes (P>0.05), but for carbohydrates, including starch and glucose, the blue fox revealed higher digestibility values. The superior digestive capacity for carbohydrates in blue fox might be a result of a long-term selection of animals digesting dietary carbohydrates more efficiently, or that an early age exposition to dietary carbohydrates has given permanent improvement of the carbohydrate digestion in the gut. PMID:12507608

Ahlstrøm, Øystein; Fuglei, Eva; Mydland, Liv Torunn

2003-01-01

101

Multilocus DNA fingerprints in gallinaceous birds: general approach and problems  

Microsoft Academic Search

Multilocus profiles were investigated in five different species of Galliformes (ring-necked pheasant Phasianus colchicus, Indian peafowl Pavo cristatus, Japanese quail Coturnix cotumix japonica, domestic chicken Gallus gallus, and red grouse Lagopus lagopus scoticus) using two human multilocus probes (33.6 and 33.15) in combination with each of four restriction enzymes (AluI, DdeI, HaeIII or HinfI). All the species show a DNA

O Hanotte; M W Bruford; T Burke

1992-01-01

102

J. Field Ornithol.,64(4):575-586 INVESTIGATOR DISTURBANCE AND CLUTCH  

E-print Network

CAMADAS DE INDIVIDUOS DE LAGOPUS LAGOPUS Sinopsis.--Utilizandotres t6cnicasdiferentesse estudi6,en dospoblacionesde Lagopus lagopus,el posibleefectodel disturbiocausadopor el investigadoren la depredaci6nde camadas

Thomas, Len

103

Humoral immune response in adult blue foxes (Alopex lagopus) after oral infection with Encephalitozoon cuniculi spores.  

PubMed

Encephalitozoon cuniculi causes severe diseases in blue fox puppies. When pregnant vixens are infected, parasites are transmitted over the placenta to the unborn that subsequently develop encephalitozoonosis. Adult foxes themselves do not have signs of disease, but show antibody titres to E. cuniculi. The purpose of the present study was to gain information on the immune response in adult foxes after experimental infection. Sixteen foxes were infected orally with E. cuniculi spores, eight of them twice and 28 days apart. The two groups of animals showed elevated serological values in both the carbon immunoassay and in the ELISA. Elevated serological levels were recorded up to 1 year after the infection took place. The control group (n=8) remained serologically negative throughout the trial. The results of the study showed that blue foxes could be seropositive for at least a year after oral infection with E. cuniculi. PMID:12719134

Akerstedt, Johan

2003-05-01

104

Fertilization in vitro of oocytes matured in vivo in the blue fox (Alopex lagopus).  

PubMed

Six unmated blue fox vixens were killed 2-3 days after peak vaginal electrical resistance. Measurements of luteinizing hormone (LH) showed that this corresponded to a time period of 6-10 days after the preovulatory LH peak in these vixens. A total of 63 ova were collected from the oviducts of the vixens, and 45 of the ova were used for study of fertilization in vitro. The ova were placed in 50 microliter droplets of fertilization medium and inseminated with 15,000-45,000 frozen-thawed silver fox spermatozoa that had been separated by swim-up technique, except for nine ova that served as controls for parthenogenesis. Only two of the 36 inseminated ova, both from a vixen killed 6 days after the preovulatory LH peak and inseminated with 15,000 spermatozoa, developed past the four-cell stage. One reached the morula stage 144 h after insemination. Despite a low success rate, the present experiment shows that fox ova matured in vivo may be fertilized and undergo initial embryonic development in vitro. PMID:8229929

Farstad, W; Hyttel, P; Grøndahl, C; Krogenaes, A; Mondain-Monval, M; Hafne, A L

1993-01-01

105

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

106

Fertilization and early embryonic development in the blue fox (Alopex lagopus).  

PubMed

A total of 15 blue fox vixens aged 1-6 years were mated, 12 once on the first day of estrus and three a second time 48 hr after the first mating, and were killed 4 hr to 8 days following mating. Ova were collected from the oviducts, evaluated by stereomicroscopy, and studied by transmission (TEM; N = 49, 12 vixens) or scanning (SEM, N = 11, three vixens) electron microscopy. At 0-3 days after ovulation, the ova had not cleaved and were at different stages of meiotic maturation. In about one-half of these ova, representing all stages of meiotic maturation, a decondensing sperm head without nuclear envelope or a small pronucleus with partial nuclear envelope was observed. No clear relationship was found between maternal meiotic stage and the stage of paternal pronucleus formation. Sperm tails were never identified in the ooplasm. Cortical granules were released after sperm penetration at early stages of meiotic maturation. Thus the block against polyspermic penetration was activated during maturation of the oocyte. The first two-cell stage appeared 4 days after ovulation (3 days after mating), the first four-cell stage the following day (day 5), and the first eight-cell stage 6 days after ovulation (5 days after mating). In a single vixen mated late (7 days postovulation) two- to four-cell stages appeared the following day (day 8). This indicates that the time required for the first cleavage division decreases with increasing interval from ovulation to mating.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8286115

Farstad, W; Hyttel, P; Grøndahl, C; Mondain-Monval, M; Smith, A J

1993-11-01

107

Complex housing environment for farmed blue foxes (Vulpes lagopus): use of various resources.  

PubMed

The present study was designed to measure the use of various, simultaneously available resources in a complex housing environment in juvenile blue foxes. Twelve blue fox sibling (male-female) pairs were housed in two-section experimental cages from the age of 8 weeks until the age of 7 months (from June to December). Each experimental cage was furnished with two platforms, a nest box, a sand box and a wooden block. This housing set-up provided the foxes with social contact, and an opportunity for oral manipulation, scratching and nesting, as well as the choice of staying on a solid floor material or on an elevated location. The foxes' behaviour was recorded at three time points during autumn (September, November and December). The foxes used all available resources. The most utilised resource was the nest box, possibly because it could be utilised in several ways (as a shelter, an elevated location, an object for scratching and for oral manipulation). The foxes also stayed more in the cage section containing the nest box than in the cage section containing a sand box. The foxes rested much on the cage floor, but they also used the interior of the nest box and elevated locations for resting. Social contact often occurred during resting. Thus, the nest box and elevated location, in conjunction with social contact seem to be valuable while resting. While active, the foxes utilised the cage floor and roof of the nest box instead of the platforms. Scratching, digging and an interaction with the wooden block were seldom observed. Activity occurred mainly on the 'empty' cage area. In conclusion, all studied resources provided blue foxes with a distinct value, as they all were used in the complex housing environment. The nest box is used most and for most variable behaviours. PMID:23481620

Koistinen, T; Korhonen, H T

2013-08-01

108

Electron microscopy of intestinal adenomatosis in the blue fox, Alopex lagopus.  

PubMed

Scanning electron microscopy of adenomatous intestinal tissue in the blue fox revealed an irregular surface topography of the colon with increased diameter of the crypt openings and prominent ridge formations between crypts. The ileum showed villous atrophy and fusion. Microvilli were short and irregular. Small ulcerations of intestinal mucosa were seen. Freeze-fracture revealed curved intracellular organisms in the altered epithelial cells. Transmission electron microscopy showed features associated with immaturity and high protein synthesis. Filamentous extensions from the basolateral plasma membrane of altered epithelial cells sometimes penetrated the basal lamina. The cytoplasm contained numerous polyribosomes, nuclei had many indentations and large and irregular nucleoli. Intracellular bacteria, with morphology corresponding to Campylobacter spp. were found in the apical epithelial cytoplasm. No host-cell-derived membrane was seen to surround the bacteria. PMID:2365844

Eriksen, K; Landsverk, T

1990-04-01

109

[A variation of secondary sex ratio in blue fox (Alopex lagopus L.)].  

PubMed

The effects of several genotypic and paratypic factors on the secondary (at birth) sex ratio was analyzed in blue fox bred in captivity. In particular, variation of sex ratio was for the first time studied as dependent on sire's age (without considering dam's age), the ages of both sire and dam, and the lines of both parents. The initial data were obtained from the Pushkino breeding facility, Moscow oblast. In total, 15,396 puppies were analyzed. The frequency of males (P) in this population was 0.551 +/- 0.004 (confidence interval 0.543 < p < 0.559). Parents' ages and litter size had no effect on the proportion of males in the progeny. In one of the two blue fox subpopulations under study, dam's line proved to be associated with a significant departure of sex ratio to a higher proportion of males, suggesting the effect of genotypic factors on the variation of secondary sex ratio in blue fox. PMID:12449653

Beketov, S V; Kashtanov, S N

2002-10-01

110

Soluble Mn2+-dependent adenylate cyclase activity in the testis of the blue fox (Alopex lagopus).  

PubMed

Soluble Mn2+-dependent adenylate cyclase (MnAC) activity was found in testicular cytosol from blue foxes castrated during the breeding season. The rate of MnAC activity was approximately constant for 30 min at 35 degrees C and for 2 hr after storage at 25 degrees C. Activity was directly proportional to cytosol protein concentration and was optimal in the physiological pH range. Enzyme activity declined in the presence of an alkylating agent (N-ethyl maleimide, NEM) and was eliminated at a concentration of 1 mM NEM. Low concentrations (0.1-10 mM) of a reducing agent (beta-mercapto ethanol, beta ME) did not increase MnAC activity, whereas a high concentration (100 mM) led to a significant reduction (p less than 0.01) in activity. Substitution of Mn2+ in the assay medium with Mg2+ led to a total loss of enzyme activity, which could not be regained by adding hormones or by preincubation of cytosol for 60 min. The Km for Mn2+ was estimated to be 3.5 mM. The affinity of the enzyme for Mn2+ was not altered by varying the concentration of ATP. In contrast, increasing concentrations of Mn2+ appeared to increase the affinity of the enzyme for MnATP2-. The Km for MnATP2- thus varied from 6 to 18 mM. PMID:6508430

Smith, A J; Jahnsen, T; Attramadal, H; Hansson, V

1984-01-01

111

Genetic parameters of pelt character, feed efficiency and size traits in Finnish blue fox (Vulpes lagopus).  

PubMed

Pelt character traits (size, quality, colour clarity, darkness) are important economic traits in blue fox breeding. Better feed efficiency (FE) is another economically important and new breeding goal for fur animals. The purpose of this study was to determine the correlations between pelt character traits, FE and size traits and to estimate genetic parameters for pelt character traits. Pelt size (pSIcm ) had a high positive genetic correlation with animal grading size (gSI), final body weight (BWFin), body length and daily gain (DG), and a moderate correlation with body condition score (BCS). Animal body length and BCS (describing fatness) were considered as genetically different traits. Genetic correlations between pelt quality and size traits were estimated without precision and did not differ from zero, but colour clarity (pCL) had a low antagonistic genetic correlation with FE. Pelt size and DG had a favourable genetic correlation with FE but a fairly high unfavourable genetic correlation with dry matter feed intake. The current emphasis on selection for larger animal and pelt size improves FE indirectly, but selection for larger pelt size favours fast-growing and fat individuals and simultaneously increases feed intake. The detected genetic connections between FE, size, feed intake and pCL should be taken into account in the Finnish blue fox breeding programme. PMID:24236607

Kempe, R; Koskinen, N; Strandén, I

2013-12-01

112

Den use by arctic foxes (Alopex lagopus) in a subarctic region of western Alaska  

USGS Publications Warehouse

Distribution, abundance, and use of arctic fox dens located in coastal tundra communities of the Yukon-Kuskokwim delta were determined in studies from 1985 to 1990. Dens were denser and less complex than those described in studies conducted above the Arctic Circle. Eighty-three dens of varying complexity were found in the 52-km2 study area. Nineteen dens were used by arctic foxes for whelping or rearing pups. Three females relocated litters to multiple dens; a maximum of four dens were used concurrently by pups from one litter. Although red foxes were common in the region, their use of dens in the study area was minimal. Differences in vegetation at den sites and nearby unoccupied sites were minimal. Furthermore, den sites could not be distinguished from non-den sites during aerial surveys.

Anthony, R.M.

1996-01-01

113

Photoperiod and fur lengths in the arctic fox ( Alopex lagopus L.)  

NASA Astrophysics Data System (ADS)

Pelage is seasonally dimorphic in the Arctic fox. During the winter, fur lengths for this species are nearly double similar values taken during the summer season. Considerable site-specific differences in fur length are noted. In general, body sites which are exposed to the environment when an Arctic fox lies in a curled position show greater fur lengths in all seasons and greater seasonal variations than body sites that are more protected during rest. Well-furred sites may tend to conserve heat during periods of inactivity, and scantily furred sites may tend to dissipate heat during periods of exercise. The growth of winter fur may compensate for the severe cold of the arctic winter. Changes in fur lengths indicate a definite pattern in spite of individual variations. During the fall months, fur lengths seem to lag behind an increasing body-to-ambient temperature gradient. Both body-to-ambient temperature gradients and fur lengths peak during December through February. From March through June, gradual environmental warming is accompanied by a decrease in average fur lengths. Thus, there appears to be a remarkable parallel between the body-to-ambient temperature gradient and the fur lengths. The growth of fur in the Arctic fox parallels annual changes in ambient temperature and photoperiod.

Underwood, L. S.; Reynolds, Patricia

1980-03-01

114

Characteristics of selected peripheral blood parameters in polar fox (Alopex lagopus L.) fed diets with inulin.  

PubMed

This study aimed at investigating changes in selected peripheral blood parameters in male polar foxes fed diets with different supplementation of inulin: 0.25% (group El), 0.5% (E2) and 1% (E3). The blood for analysis was sampled from the brachial vein. The study showed that adding 0.25 and 0.5% of inulin to fox feed resulted in a lower content of haemoglobin (Hb) as well as mean mass of Hb in red blood cells in the 0.5% inulin group. The total count of thrombocytes decreased significantly with a higher level of prebiotic, while the total number of white blood cells and the percentage of different leukocytes tested remained invariable. The lowest supplementation of inulin affected the partial pressure of carbon dioxide, however, the remaining acid-base parameters did not change. The present study provides the first preliminary information about the effect of dietary inulin on some haematological indices and acid-base parameters in adult polar foxes. The results may be helpful in practice to improve the health condition of farmed polar foxes. PMID:23767302

Szymeczko, Roman; G?owi?ska, Beata; Burlikowska, Katarzyna; Piotrowska, Anna; Bogus?awska-Tryk, Monika; Koz?owska, Izabela; Brudnicki, Adam; Pietruszy?ska, Dominika

2013-01-01

115

Evidence for energy savings from aerial running in the Svalbard rock ptarmigan (Lagopus muta hyperborea).  

PubMed

Svalbard rock ptarmigans were walked and run upon a treadmill and their energy expenditure measured using respirometry. The ptarmigan used three different gaits: a walking gait at slow speeds (less than or equal to 0.75 m s(-1)), grounded running at intermediate speeds (0.75 m s(-1) < U < 1.67 m s(-1)) and aerial running at high speeds (greater than or equal to 1.67 m s(-1)). Changes of gait were associated with reductions in the gross cost of transport (COT; J kg(-1) m(-1)), providing the first evidence for energy savings with gait change in a small crouched-postured vertebrate. In addition, for the first time (excluding humans) a decrease in absolute metabolic energy expenditure (rate of O(2) consumption) in aerial running when compared with grounded running was identified. The COT versus U curve varies between species and the COT was cheaper during aerial running than grounded running, posing the question of why grounded running should be used at all. Existing explanations (e.g. stability during running over rocky terrain) amount to just so stories with no current evidence to support them. It may be that grounded running is just an artefact of treadmill studies. Research investigating the speeds used by animals in the field is sorely needed. PMID:21288943

Nudds, R L; Folkow, L P; Lees, J J; Tickle, P G; Stokkan, K-A; Codd, J R

2011-09-01

116

Molecular characterization of repetitive DNA sequences from B chromosome in Plantago lagopus L.  

PubMed

In Plantagolagopus the B chromosome has been reported by our laboratory to be the result of massive amplification of ribosomal DNA sequences. However, the presence of transposable elements and other repetitive DNA sequences together with rDNA could not be ruled out. The present study clearly demonstrated the presence of transposable elements in the B chromosomes. These transposable elements were characterized and their nature assessed. Physical mapping using double fluorescent in situ hybridization was performed using DNA probes for 5S and copia elements. The results clearly proved that the B chromosome is a mix of 5S, 45S rDNA and transposable elements. Based on the FISH and Fiber-FISH patterns, it can be concluded that while 45S rDNA sequences are restricted to the subtelomeric regions, the 5S rDNA sequences are interspersed with transposons in the body of the B chromosome. These results have further enhanced our understanding of the organization and evolution of B chromosomes. PMID:24296743

Kour, G; Kaul, S; Dhar, M K

2014-01-01

117

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

118

The Condor 115(1):2839 The Cooper Ornithological Society 2013  

E-print Network

in the Aleutian Archipelago have been greatly reduced by introduced arctic foxes (Alopex lagopus). We analyzed (Alopex lagopus). Analizamos datos de microsatélites, intrones nucleares y loci mitocondriales (ADNmt

McCracken, Kevin G.

119

Kinematics and subpopulations' structure definition of blue fox (Alopex lagopus) sperm motility using the ISAS® V1 CASA system.  

PubMed

Over recent years, technological advances have brought innovation in assisted reproduction to the agriculture. Fox species are of great economical interest in some countries, but their semen characteristics have not been studied enough. To advance the knowledge of function of fox spermatozoa, five samples were obtained by masturbation, in the breeding season. Kinetic analysis was performed using ISAS® v1 system. Usual kinematic parameters (VCL, VSL, VAP, LIN, STR, WOB, ALH and BCF) were considered. To establish the standardization for the analysis of samples, the minimum number of cells to analyse and the minimum number of fields to capture were defined. In the second step, the presence of subpopulations in blue fox semen was analysed. The minimum number of cells to test was 30, because kinematic parameters remained constant along the groups of analysis. Also, the effectiveness of ISAS® D4C20 counting chamber was studied, showing that the first five squares presented equivalent results, while in the squares six and seven, the kinematic parameters showed a reduction in all of them, but not in the concentration or motility percentage. Kinematic variables were grouped into two principal components (PC). A linear movement characterized PC1, while PC2 showed an oscillatory movement. Three subpopulations were found, varying in structure among different animals. PMID:24890953

Soler, C; García, A; Contell, J; Segervall, J; Sancho, M

2014-08-01

120

[Effect of the hereditary characteristics of male blue foxes Alopex lagopus L. on the sex ratio of their offspring].  

PubMed

Family analysis of a commercial population of the blue fox (the Pushkinskoe Breeding Fur Farm, Moscow oblast) with respect to secondary sex ratio has been performed. The offspring of each individual male or female involved in crossing between 1984 and 1988 was analyzed. The study of all families formed by every male and every female has made it possible to determine a group of "outstanding" fathers (23 out of 287 males), whose offspring was predominantly male (62.1% of the offspring were males, versus 53.9% in the total population). The results of subsequent detailed study on the pedigrees of male blue foxes in whose offspring the sex ratio significantly deviates from 1:1 indicate that this character is transmitted from fathers to sons without the deterioration of other commercially valuable characters. It is presumed that the significant deviation of sex ratio from 1:1 in the offspring of some male blue foxes is determined by genetic factors. PMID:15865299

Beketov, S V; Kashtanov, S N

2005-03-01

121

The spermatogenic cycle in the blue fox (Alopex lagopus): relative frequency and absolute duration of the different stages.  

PubMed

The spermatogenic cycle of the blue fox was divided into eight distinct stages, based on an analysis of different cell associations of the seminiferous epithelium. The criteria used for classification of the stages were the type of spermatogonia, the occurrence of meiotic figures, and the shape and location of spermatids. The relative frequencies of the stages I to VIII were 25.7, 9.8, 8.7, 5.9, 13.8, 9.9, 10.6 and 15.5%, respectively. The duration of one cycle of the seminiferous epithelium was 12.0 +/- 0.2 days as determined from the progression of 5-bromo-2-deoxyuridine (BrdU)-labelled cells at various time intervals. The absolute duration of stages I to VIII was calculated to be 3.1, 1.2, 1.0, 0.6, 1.7, 1.2, 1.3 and 1.9 days, respectively. The estimated life span of primary spermatocytes was 19.2 days, of secondary spermatocytes less than 0.6 days, of spermatids with round nuclei 9.2 days and of spermatids with elongated nuclei 8.9 days. PMID:2387650

Andersen Berg, K; Clausen, O P; Huitfeldt, H S

1990-08-01

122

Effect of melatonin implantation on the seasonal variation of FSH secretion in the male blue fox (Alopex lagopus).  

PubMed

A heterologous radioimmunoassay system developed for the sheep was shown to measure FSH in the plasma of the blue fox. FSH concentrations throughout the year showed a circannual rhythm with the highest values (61.6 +/- 14.8 ng/ml) occurring shortly before or at the onset of the mating season, a pattern similar to that of LH. The concentration of FSH then declined when androgen concentrations and testicular development were maximal at the time of the mating season (March to May). Thereafter, concentrations remained low (25.2 +/- 4.1 ng/ml) in contrast to those of LH. Implantation of melatonin in August and in February maintained high plasma values of FSH after the mating season (142.3 +/- 16.5 ng/ml) in association with a maintenance of testicular development and of the winter coat. The spring rise of prolactin was suppressed by melatonin treatment. The release of FSH after LHRH injection was also increased during this post-mating period in melatonin-treated animals, in contrast to the response of the control animals which remained low or undetectable. These results suggest that changes both in the secretions of FSH and prolactin may be involved in the prolongation of testicular activity and in the suppression of the spring moult after melatonin administration. PMID:3135390

Mondain-Monval, M; Smith, A J; Simon, P; Møller, O M; Scholler, R; McNeilly, A S

1988-05-01

123

Seasonal variations of LH, prolactin, androstenedione, testosterone and testicular FSH binding in the male blue fox (Alopex lagopus).  

PubMed

The seasonal changes in testicular weight in the blue fox were associated with considerable variations in plasma concentrations of LH, prolactin, androstenedione and testosterone and in FSH-binding capacity of the testis. An increase in LH secretion and a 5-fold increase in FSH-binding capacity were observed during December and January, as testis weight increased rapidly. LH levels fell during March when testicular weight was maximal. Plasma androgen concentrations reached their peak values in the second half of March (androstenedione: 0.9 +/- 0.1 ng/ml: testosterone: 3.6 +/- 0.6 ng/ml). A small temporary increase in LH was seen in May and June after the breeding season as testicular weight declined rapidly before levels returned to the basal state (0.5-7 ng/ml) that lasted until December. There were clear seasonal variations in the androgenic response of the testis to LH challenge. Plasma prolactin concentrations (2-3 ng/ml) were basal from August until the end of March when levels rose steadily to reach peak values (up to 13 ng/ml) in May and June just before maximum daylength and temperature. The circannual variations in plasma prolactin after castration were indistinguishable from those in intact animals, but LH concentrations were higher than normal for at least 1 year after castration. PMID:3930711

Smith, A J; Mondain-Monval, M; Møller, O M; Scholler, R; Hansson, V

1985-07-01

124

Handling during pregnancy in the blue fox (Alopex lagopus): the influence on the fetal pituitary-adrenal axis.  

PubMed

Previous studies revealed that handling is a stressor for farmed blue foxes. The present study was designed to examine the effects of a 1-min daily handling stress applied to pregnant blue fox vixens on the function of the fetal pituitary-adrenal system. Plasma concentrations of adrenocorticotropin hormone (ACTH), cortisol, and progesterone, adrenal content of cortisol and progesterone, in vitro adrenal production of these steroids and response to ACTH, and adrenal weights were measured in control (C; n = 73) and stressed (S; n = 58) fetuses. The ACTH levels were lower in stressed fetuses than in the controls (C: males, 128.6 +/- 6.1 pg/ml; females, 165.9 +/- 6.1 pg/ml; S: males, 122.3 +/- 5.4 pg/ml; females, 145.0 +/- 8.1 pg/ml; P < 0.05). In contrast, increased plasma cortisol concentrations in both sexes were demonstrated in stressed compared with control fetuses (C: males, 9.2 +/- 0.4 ng/ml; females, 9.2 +/- 0.4 ng/ml; S: males, 11.8 +/- 0.7 ng/ml; females, 13.2 +/- 0.7 ng/ml; P < 0.00001). The same difference was observed in plasma progesterone concentrations (C: males, 1.54 +/- 0.07 ng/ml; females, 1.49 +/- 0.10 ng/ml; S: males, 1.86 +/- 0.11 ng/ml; females, 1.74 +/- 0.10 ng/ml; P < 0.01). Prenatal stress did not change the baseline adrenal production of cortisol but prevented the cortisol response to ACTH in female fetuses and decreased the progesterone production in both sexes. Additionally, prenatally stressed fetuses of both sexes had significantly lower adrenal weights than controls (C: males, 9.4 +/- 0.3 mg; females, 9.5 +/- 0.4 mg; S: males, 8.1 +/- 0.3 mg; females, 8.2 +/- 0.4 mg; P < 0.001). These results indicate that prenatal handling stress induces a dysregulation of the pituitary-adrenal axis in the fetus and suggest that increased plasma glucocorticoids in the stressed dam can cross the placenta and influence the fetal hypothalamicpituitary-adrenal axis. PMID:11551111

Osadchuk, L V; Braastad, B O; Hovland, A L; Bakken, M

2001-07-01

125

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

126

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

PubMed

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. PMID:21858505

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

2011-10-01

127

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

128

POPULATION ECOLOGY Brett K. Sandercock Kathy Martin Susan J. Hannon  

E-print Network

ptarmigan (Lag- opus lagopus) breeding at arctic and subalpine sites, and white-tailed ptarmigan (L for conservation of the bio- logical resources of arctic and alpine ecosystems. Keywords Conservation Æ Lagopus Æ

Sandercock, Brett K.

129

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

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

Aldridge, Cameron

130

Published by the Wilson Ornithological Society VOL. 122, NO. 1 March 2010 PAGES 1206  

E-print Network

population of Evermann's Rock Ptarmigan (Lagopus muta evermanni) in the Near Islands group of the western Ptarmigan (Lagopus leucura) (Braun et al. 1978, Hoffman and Giesen 1983, Clarke and Johnson 1990) and Ruffed

Sandercock, Brett K.

131

Osnabrcker Naturwissenschaftliche Mitteilungen Band 35, S. 201208, 2009  

E-print Network

Brut durch Fressfeinde wie den Eisfuchs (Alopex lagopus) oder die Eismöwe (Larus hyperboreus) gefährdet by predators like polar foxes (Alopex lagopus) or Glacous Gulls (Larus hyperboreus). In this review we compare

Kleyer, Michael

132

Conservation Genetics ISSN 1566-0621  

E-print Network

's Rock Ptarmigan (Lagopus muta evermanni) at Agattu Island, in the western Aleutian Archipelago, Alaska population size Á Inbreeding avoidance Á Lagopus muta Á Reintroduction Introduction A common goal for species

Sandercock, Brett K.

133

Copyright 2009 by the author(s). Published here under license by the Resilience Alliance. Lavers, J. L., I. L. Jones, G. J. Robertson, and A. W. Diamond. 2009. Contrasting population trends at two  

E-print Network

, illegal and incidental to the murre (Uria sp.) hunt, and fox (Alopex lagopus) predation on Razorbill (Alca lagopus) sur le Petit Pingouin (Alca torda). Deux populations de Petits Pingouins ont été comparées : une

Jones, Ian L.

134

Molecular Ecology (2000) 9, 12651278 2000 Blackwell Science Ltd  

E-print Network

vicariance and historical biogeography of rock ptarmigan (Lagopus mutus) in the Bering region K. HOLDER, R (Lagopus mutus) endemic to the Aleutian Archipelago. To do this we examined patterns of genetic

Montgomerie, Bob

2000-01-01

135

ANIMAL BEHAVIOUR, 2003, 65, 297307 doi:10.1006/anbe.2003.2063, available online at http://www.sciencedirect.com  

E-print Network

, as associates in preference to rough-legged buzzards, Buteo lagopus, even though the latter were several times lagopus, showed that this could be explained by differences in nest defence intensity, rather than habitat

Black, Jeff

136

RESEARCH ARTICLE Divergence in an archipelago and its conservation consequences  

E-print Network

endemic Á Genetic diversity Á Lagopus muta Á Rock ptarmigan Introduction Organisms found on oceanic). The most geo- graphically variable of these species is the rock ptarmigan (Lagopus muta), a holarctic by the introduction of arctic foxes (Alopex lagopus) during the 1700s (Croll et al. 2005). Native mammals are absent

Winker, Kevin

137

Original article Sleeping distance in relation to sexual state  

E-print Network

in sleeping distance. sleeping distance I sexual state I social status I Alopes lagopus== Arctic blue fox renards arctiques (Alopex lagopus, 3 mâles et 3 femelles) en relation avec l'état de ré- ceptivité groupe de renards arctiques. distance de repos / oestrus / hiérachie sociale /Alopes lagopus = renard

Paris-Sud XI, Université de

138

Introduction In southern Europe, the end of the Palaeolithic is char-  

E-print Network

of Bird exploitation pattern: the case of Ptarmigan Lagopus sp. in the Upper Magdalenian site of La Vache, France Abstract / Zusammenfassung This paper deals with the exploitation of Ptarmigan (Lagopus sp Beitrag wird auf die Nutzung des Schneehuhnes (Lagopus sp.) im Spätmagdalenien eingegangen. Grund- lage

Paris-Sud XI, Université de

139

VOL. 53, NO. 1 (MARCH 2000) P. 5360 Low Abundance of King Eider Nests during Low Lemming Years  

E-print Network

cyclic fluctuations in northern ecosystems. Key words: arctic fox, Alopex lagopus, collared lemming polaire, Alopex lagopus, prédation, cycles des populations, Groenland 1 Institut für Landespflege are the cyclic dynamics of predators such as arctic foxes (Alopex lagopus) and snowy owls (Nyctea scandiaca

Helsinki, University of

140

Non-invasive faecal steroid monitoring of ovarian and adrenal activity in farmed blue fox (Alopex lagopus) females during late pregnancy, parturition and lactation onset.  

PubMed

In the semi-domesticated blue fox, handling stress may influence reproductive performance and increase perinatal pup loss. Ovarian and adrenal steroids were analysed in faecal samples collected from mid-gestation through the first week of lactation in 40 female blue foxes to characterize hormone patterns during this important reproductive period. Daily faecal samples were collected from 40 foxes during 30 pregnancies, one late abortion and nine bred-matched non-pregnancies. Mean concentrations of faecal progestagens over the 10 days before birth were significantly higher in pregnant compared to non-pregnant females (51+/-1.50 microg/g versus 36+/-3.72 microg/g, respectively; P < 0.01). From 10 to 3 days before whelping, total faecal oestrogen concentrations also were higher (P < 0.01) in pregnant (1082+/-41.69 ng/g) than non-pregnant (628+/-72.43 ng/g) foxes, before declining to non-pregnant values (402+/-24.88 ng/g) after parturition. Overall mean faecal corticoid concentrations from 3 to 20 days before whelping differed between pregnant and non-pregnant foxes (128+/-3.11 ng/g versus 103+/-5.86 ng/g, respectively; P < 0.01). Furthermore, in pregnant foxes, corticoid excretion increased further from 2 days before to 3 days after whelping (216+/-13.71 ng/g; P < 0.01). Thereafter, corticoid concentrations were similar between pregnant and non-pregnant females (P > 0.05). In sum, the faecal steroid hormone patterns for oestrogens and progestagens were similar to those previously obtained by analyses of fox serum hormones, with both steroids being higher in pregnant than non-pregnant foxes at the end of gestation. The elevation in corticoid concentrations in pregnant females suggests that adrenal activation is involved in the initiation of parturition in the blue fox. Thus, faecal steroid analyses can be used to monitor ovarian activity during pregnancy and pseudopregnancy in farmed blue fox females. PMID:15911180

Sanson, Gorm; Brown, Janine L; Farstad, Wenche

2005-07-01

141

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

142

Seasonal changes in testicular structure and function in the blue fox (Alopex lagopus), as quantified by morphometric analysis and measurement of adenylate cyclase activity.  

PubMed

The volume of the blue fox testis showed 5-fold changes during the year, associated with considerable changes in cellular composition. The seminiferous epithelium was maximally regressed in August, when 94% of tubules contained only spermatogonia. By late October, approximately 6 months before the mating season, 40% of tubules contained primary spermatocytes. From the middle of January until the end of April all tubules contained spermatids or more advanced haploid cells. Tubular diameter increased by 73% during testicular re-development, and epithelial height increased 3-fold. Regression to the basal state occurred during May to July. The volume densities of the seminiferous epithelium and of interstitial tissue remained approximately constant throughout the year. Soluble Mn2+-dependent adenylate cyclase activity showed seasonal variations that paralleled those of the haploid germ cell population and testicular volume, whereas somatic cell adenylate cyclase activity was relatively constant. PMID:3744586

Smith, A; Bugge, H P; Berg, K A; Møller, O; Hansson, V

1986-02-01

143

Centric-fusion translocation and whole-arm heterochromatin in the karyotype of the blue fox (Alopex lagopus L.): synaptonemal complex analysis.  

PubMed

Conventional observations of mitotic chromosomes from two male blue foxes, revealing a centric-fusion translocation and whole-arm heterochromatin, were verified by synaptonemal complex analysis. This analysis revealed that the centric fusion had been preceded by a conspicuous loss of chromosome material in the two one-armed chromosomes involved, but the chromosomal origin of the centric-fusion kinetochore could not be established. The nontranslocated chromosomes of the trivalent, which in all cells but one were in cis configuration, had reached by early pachytene a stage in which almost complete homologous pairing and nonhomologous association or pairing of the free ends of the chromosomes could be observed. In later stages, complete pairing of the nontranslocated chromosomes with the corresponding arms of the centric-fusion translocation was seen occasionally. One to six autosomal bivalents demonstrated unpaired heterochromatic arms in early pachytene, and the heterochromatic chromosome arms were sometimes unpaired even in late pachytene. Some of them showed a distinct size heteromorphism in late zygotene and early pachytene. In most late-pachytene cells, however, the heteromorphic chromosomes were completely length-adjusted. Only a small fraction of the cells showed pairing interference between nonhomologous chromosomes. PMID:1855385

Swito?ski, M; Gustavsson, I

1991-01-01

144

Effect of dietary glycine and benzoate level on benzoate metabolism in mink (Mustela vision), blue fox (Alopex lagopus), and raccoon dog (Nyctereutes procyonoides).  

PubMed

Three 2 x 4 factorial experiments were carried out from August to September with 30 juvenile male mink, 24 raccoon dogs, and 24 blue foxes to investigate the effect of dietary glycine supply (low or high) on the efficiency of these species to excrete hippuric acid with incremental benzoate intake (0, 1, 2, or 4 mmol/kg BW). For mink, two additional treatments with 1 or 2 mmol/kg BW of ethyl benzoate were included. A basal low-glycine diet was formulated to meet the minimum protein requirements of fur animals (30% of ME). This diet was supplemented with 0 or 3 g/kg of glycine, or with 0, 1.0, 2.07, or 4.15 g/kg of sodium benzoate for mink and blue foxes, and with 0 or 4.5 g/kg of glycine and 0, 1.58, 3.17, or 6.34 g/kg of sodium benzoate for raccoon dogs, respectively. Two additional diets with .76 or 1.53 g/kg of ethyl benzoate were made for mink. Fecal and urinary benzoic and hippuric acid excretion were measured for 3 d. The 24-h recovery of [14C]benzoic acid injected intraperitoneally was measured from urine, the liver, and the kidneys. All animals appeared healthy and no clinical signs of benzoate overdose were observed. Dietary benzoate level did not affect ADFI or ADG in any species. Glycine supplementation lowered ADFI in mink. The majority of ingested benzoates were absorbed from the gut (over 95%), except in blue foxes, which excreted 6 to 15% of ingested benzoates in feces with incremental increases in benzoate intake. Urinary free benzoic acid excretion accounted for 10% of the ingested benzoates in blue foxes but less than 5% in mink and raccoon dogs. When benzoate intake was 1 mmol/kg BW, mink, blue foxes, and raccoon dogs excreted 71, 77, and 34% of ingested benzoates as hippuric acid in urine, respectively. With higher benzoate intakes, urinary hippuric acid excretion decreased quadratically with mink to 20%, and linearly with blue foxes and raccoon dogs to 45 and 16%, respectively. The hippuric acid pathway appears to be the principal route of benzoate elimination in the mink and blue fox, whereas, in the raccoon dog, other pathways appear to be more important. In mink, the elimination of ethyl benzoate did not differ from that of sodium benzoate. Because glycine conjugation is the primary route of benzoate elimination, it is recommended that benzoate content in fur animal feeds should not exceed 1 g/kg feed on an as-fed basis. PMID:10784188

Pölönen, I J; Partanen, K H; Jalava, T K; Toivonen, V F

2000-04-01

145

Effects of melatonin implantation on spermatogenesis, the moulting cycle and plasma concentrations of melatonin, LH, prolactin and testosterone in the male blue fox (Alopex lagopus).  

PubMed

Melatonin administration to male blue foxes from August for 1 year resulted in profound changes in the testicular and furring cycles. The control animals underwent 5-fold seasonal changes in testicular volume, with maximal values in March and lowest volumes in August. In contrast, melatonin treatment allowed normal redevelopment of the testes and growth of the winter coat during the autumn but prevented testicular regression and the moult to a summer coat the following spring. At castration in August, 88% of the tubular sections in the testes of the controls contained spermatogonia as the only germinal cell type, whereas in the treated animals 56-79% of sections contained spermatids or even spermatozoa. Semen collection from a treated male in early August produced spermatozoa with normal density and motility. Measurement of plasma prolactin concentrations revealed that the spring rise in plasma prolactin values (from basal levels of 1.6-5.4 ng/ml to peak values of 4.1-18.3 ng/ml) was prevented; values in the treated animals ranged during the year from 1.8 to 6.3 ng/ml. Individual variations in plasma LH concentrations masked any seasonal variations in LH release in response to LHRH stimulation, but the testosterone response to LH release after LHRH stimulation was significantly higher after the mating season in the treated animals, indicating that testicular testosterone production was maintained longer than in the controls. The treated animals retained a winter coat, of varied quality and maturity, until the end of the study in August. PMID:3572874

Smith, A J; Mondain-Monval, M; Andersen Berg, K; Simon, P; Forsberg, M; Clausen, O P; Hansen, T; Møller, O M; Scholler, R

1987-03-01

146

Isolates of Encephalitozoon cuniculi from farmed blue foxes (Alopex lagopus) from Norway differ from isolates from Swiss domestic rabbits (Oryctolagus cuniculus).  

PubMed

Encephalitozoon cuniculi has a wide host range among mammals, but whether it represents a homogeneous species is a subject of controversy. We have isolated, cultivated (in human MRC-5 cells) and, for the first time, characterized by immunological and molecular biological methods four isolates of E. cuniculi from Norwegian blue foxes with a history of encephalitozoonosis. The isolates were compared with nine isolates from domestic rabbits from Switzerland. Two E. cuniculi subtypes were identified according to their host species. A 5'-GTTT-3' tetranucleotide repeat was present twice in the rDNA intergenic spacer in all isolates from foxes as opposed to three times in all isolates from rabbits. Furthermore, random amplified polymorphic DNA analysis showed one polymorphic band among the subtypes, and Western-blot analysis using serum from an infected fox discriminated between the two subtypes on the basis of their banding patterns in the ranges of 31-33 and 38-40 kDa. The 5'-GTTT-3' tetranucleotide repeat is a valuable genetic marker for these two subtypes of E. cuniculi and will be of use in continued studies on the molecular epidemiology of this parasite. PMID:8897508

Mathis, A; Akerstedt, J; Tharaldsen, J; Odegaard, O; Deplazes, P

1996-01-01

147

Preliminary studies of the effects of bromocriptine on testicular regression and the spring moult in a seasonal breeder, the male blue fox (Alopex lagopus).  

PubMed

Bromocriptine administration in the form of slow-release injections to male blue foxes during March-May abolished the normal spring rise in plasma prolactin concentrations seen in May and June. The spring moult was prevented and the treated animals retained a winter coat of varied quality and maturity until the end of the study in August. Plasma testosterone concentrations fell normally from March until August. Testicular regression was, however, delayed, although there were individual variations in response. Estimation by DNA flow cytometry in early July of the relative numbers of haploid, diploid and tetraploid cells in the testis showed that, in the treated animals, 74-80% of the cells were haploid (maturing germinal cells), 4-6% tetraploid (mainly primary spermatocytes) and the rest diploid cells (somatic cells and the remaining germinal cell types). In the control males, however, no haploid cells were detected and the majority of cells were diploid (93-99%). At castration in August, histological examination revealed various stages of testicular regression in the treated and control animals. PMID:3430468

Smith, A J; Mondain-Monval, M; Simon, P; Andersen Berg, K; Clausen, O P; Hofmo, P O; Scholler, R

1987-11-01

148

The effect of different fat sources in the diet on the composition of adipose tissue in arctic foxes (Alopex lagopus L.).  

PubMed

The study investigated the effect of vegetable and animal fat in the feed ration on the fatty acid profile of reserve fat in the arctic fox. Varying proportions of saturated and unsaturated fats in the feed ration comprised the experimental factor. In order to differentiate contents of saturated and unsaturated fatty acids in the experimental feed rations, various percentages of rapeseed oil and turkey fat were applied. The subcutaneous and circum-organal fat in this study differed considerably in terms of contents of individual fatty acids and between individual groups of acids. The circum-organal fat contained much higher amounts of unsaturated acids, but at the same time it was characterized by a lower amount of monounsaturated acids. Significant differences were also found in the contents of as many as 11 fatty acids. Recorded results indicate a potential modification of reserve fat in the arctic fox, a model representative of carnivorous animals (Carnivora). The possibility of the partial substitution of animal fat with vegetable oil (rape oil) in the nutritive diet of artic foxes was confirmed. PMID:25134342

Nowicki, S?awomir; Przysiecki, Piotr; Filistowicz, Aneta; Potka?ski, Andrzej; Filistowicz, Andrzej; Wójtowski, Jacek

2014-01-01

149

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

150

RELATIONSHIPS BETWEEN CLIMATE AND POPULATION DYNAMICS OF WHITE-TAILED PTARMIGAN LAGOPUS LEUCURUS IN ROCKY MOUNTAIN NATIONAL PARK, COLORADO, USA. (R827449)  

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

151

Determination of Plasma Progesterone in the Blue Fox (Alopex lagopus) at Pro-oestrus and Oestrus by Use of a Commercial Kit  

Microsoft Academic Search

A commercially available method for determination of progesterone in blood from blue fox vixens is compared to a laboratory method, and the correlation is expressed as (X, Y)= (concentration by the standard method, concentration by the commercial method, in nmol\\/l): Y=0.5130X + 27.70; n=238; r=0.8839 for comparison of all values, and Y=1.0024X + 11.05; n=177; r=0.9293 for concentrations of progesterone

René Høier

1989-01-01

152

Chemical composition of silage residues sustaining the larval development of the Culicoides obsoletus/Culicoides scoticus species (Diptera: Ceratopogonidae).  

PubMed

Culicoides (Diptera: Ceratopogonidae) are biological vectors of bluetongue virus (BTV). Bluetongue is a viral disease that affects domestic and wild ruminants. Since its recent emergence in northern Europe, this disease has caused considerable economic losses to the sheep and cattle industry. The biotopes, and more particularly the chemical characteristics which are suitable for larval development of the main vector species, are still relatively unknown. This study shows that the larvae of biting midges belonging to the species Culicoides obsoletus and Culicoides scoticus are able to breed in different types of silage residue (maize, grass, sugar beet pulp and their combinations). The chemical composition of substrates strongly influences the presence of the immature stages of these biting midges. Higher lignin and insoluble fibre contents seem to favour their presence and could play the role of a physical support for semi-aquatic larvae. In contrast, higher concentrations of magnesium and calcium are negatively correlated with the presence of these two species. These data will help to locate and monitor the breeding sites of these species and could contribute to the control of these insects on farms. PMID:22963713

Zimmer, Jean-Yves; Saegerman, Claude; Losson, Bertrand; Beckers, Yves; Haubruge, Eric; Francis, Frédéric

2013-01-16

153

Evolution of the mitochondrial DNA cytochrome b gene in Tetraonidae birds.  

PubMed

Mitochondrial fragments containing the cytochrome b gene (1020 bp in size) of four bird species belonging to four genera of the family Tetraonidae (Tetrao parvirostris, Bonasa umbellus, Lagopus lagopus scoticus, and Falcipennis falcipennis) were directly sequenced. Of the 1020 nucleotide positions, 186 were variable and uniformly distributed over the gene and only 46 were parsimony informative. Most substitutions were synonymous. Replacement substitutions were detected for 15 out of 340 amino acid sites; only four replacements were parsimony informative. The greatest codon bias was found for leucine and serine. The C-T transitions and the G-C transversions were, respectively, the most common (60.7%) and the most rare (5.9%). The mutation frequencies were high at the third codon position (85.2%) and relatively low at the first and the second position. At the third codon position of the species examined, the guanine content was the lowest (3.3%) and the cytosine content was the highest (44.5%). Based on the cytochrome b gene sequences, phylogenetic relationships in the order Galliformes are inferred. PMID:10994496

Butorina, O T; Seibold, I; Helbig, A; Solovenchuk, L L

2000-07-01

154

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

155

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

156

Identification of genes responding to nematode infection in red grouse.  

PubMed

The identification of genes involved in a host's response to parasite infection provides both a means for understanding the pathways involved in immune defence and a target for examining host-parasite co-evolution. Most studies rely on a candidate gene approach derived from model systems to identify gene targets of interest, and there have been a dearth of studies geared towards providing a holistic overview of immune response from natural populations. We carried out an experiment in a natural population of red grouse (Lagopus lagopus scoticus) to manipulate levels of Trichostrongylus tenuis parasite infection. The transcriptomic response of individuals was examined from standard cDNA and suppressive subtractive hybridization (SSH) libraries produced from gut, liver and spleen, enriching for genes expressed in response to T. tenuis infection. A total of 2209 and 3716 unique transcript sequences were identified from the cDNA and SSH libraries, respectively. Forty-five of these had Gene Ontology annotation associated with immune response. Some of these genes have previously been reported from laboratory-based studies of model species as important in immune response to gastrointestinal parasite infection; however, multiple novel genes were also identified. These may reveal novel pathways involved in the host response of grouse to T. tenuis and provide a resource that can be utilized as candidate genes in other species. All sequences described have been deposited in GenBank (accession numbers GW698221-GW706922) PMID:21429137

Webster, L M I; Mello, L V; Mougeot, F; Martinez-Padilla, J; Paterson, S; Piertney, S B

2011-03-01

157

Condition- and parasite-dependent expression of a male-like trait in a female bird.  

PubMed

In many species, females display brightly coloured and elaborate traits similar to those that males use in intra- and inter-sexual selection processes. These female characters are sometimes related to fitness, and might function as secondary sexual characteristics that have evolved through sexual selection. Here, we used descriptive data from 674 females in 10 populations and an experimental removal of Trichostrongylus tenuis parasites in four populations, to examine the effects of season, age, condition, and parasites on the size of supra-orbital combs displayed by female red grouse Lagopus lagopus scoticus. We found that comb size (i) was greater during the breeding than the non-breeding season, (ii) was greater in adult than in young females, (iii) was positively correlated with body condition, and (iv) negatively correlated with parasite abundance. Experimentally, we showed that comb size increased proportionally to the number of worms removed after parasite dosing. Our findings provide a better understanding of proximate mechanisms behind the expression of a male-like trait in females, and we discuss its possible function as a female ornament. PMID:21247939

Martinez-Padilla, J; Vergara, P; Pérez-Rodríguez, L; Mougeot, F; Casas, F; Ludwig, S C; Haines, J A; Zeineddine, M; Redpath, S M

2011-06-23

158

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

159

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

160

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

161

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

162

Sexual development in the immature male blue fox (Alopex lagopus), investigated by testicular histology, DNA flow cytometry and measurement of plasma FSH, LH, testosterone and soluble testicular Mn2+-dependent adenylate cyclase activity.  

PubMed

Testicular weight in young male blue foxes increased steadily from 12 weeks of age (0.4-0.7 g) to reach peak values at the time of the mating season in March-April (5.2-6.6 g), before declining rapidly during May to low values in August at 63 weeks of age (1.3-1.6 g). Primary spermatocytes were found in the spermatogenic epithelium at 20 weeks of age and by late December (29 weeks of age) elongated spermatids were seen. There was a good correlation between the seasonal variations in the presence of germ cell types assessed by quantitative analysis of testicular histology and the variations in numbers of haploid, diploid and tetraploid cells measured by DNA flow cytometry: no haploid cells were found before the end of November and peak numbers were observed in March. Plasma FSH concentrations were increased from December onwards (with the exception of April). There were no clearcut seasonal variations in plasma LH concentrations although values were consistently lower in April. Testosterone concentrations were low for most of the year but increased from the end of January to the middle of April. There was no detectable seasonal variation in LH release in response to LHRH injection, and no typical pattern in plasma FSH concentrations during the first 100 min after injection. Plasma testosterone concentrations after LHRH injection rose gradually during testicular development. There were large seasonal variations in soluble Mn2+-dependent adenylate cyclase activity in the testis, that paralleled the changes in testicular weight and haploid cell content. Values were low until December and reached a peak at the time of the mating season before falling to basal levels again by June. The results suggest that immature male blue foxes reach full testicular development (indistinguishable from that of older animals) by the first mating season after birth at, an age of about 40 weeks. PMID:3123658

Smith, A J; Mondain-Monval, M; Andersen Berg, K; Gordeladze, J O; Clausen, O P; Simon, P; Scholler, R

1987-11-01

163

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...

164

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

165

doi: 10.1098/rsbl.2011.1207 , 878-881 first published online 2 May 201282012Biol. Lett.  

E-print Network

rely on har- vested animals to document temporal trends. It is usually unknown whether these data harvested animals [6,11]. Harvest data, however, will not reflect popu- lation values if harvest. For example, the age distribution of shot red grouse (Lagopus lagopus scoti- cus) was biased by harvest

Festa-Bianchet, Marco

166

Soutenue le 26 novembre 2010 prsente par  

E-print Network

,version1-30Jan2014 #12;Résumé : Le lagopède alpin (Lagopus muta) et la perdrix grise (Perdix perdix pyrénéennes de ces deux sous-espèces (Lagopus muta pyrenaica et Perdix perdix hispaniensis) sont donc en

Paris-Sud XI, Université de

167

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

168

Bone lead levels and lead isotope ratios in red grouse from Scottish and Yorkshire moors.  

PubMed

Leg and foot bones of adult and juvenile red grouse (Lagopus lagopus scoticus) were collected from hunter-shot birds on two Scottish estates (Glendye and Invermark) and one Yorkshire estate in September, 2003. The lead content of bones was measured by atomic absorption spectrophotometry, and corresponding stable lead isotopes (Pb(204, 206, 207, 208)) by inductively coupled plasma mass spectrometry. At the Glendye (N=111) and Invermark (N=85) estates, relatively few birds (5.4% and 3.5%, respectively) had highly elevated bone lead concentrations (>20 microg/g dry weight). In bones of these highly exposed birds, a combination of Pb(206):Pb(207) and Pb(208):Pb(207)ratios was consistent with ingestion of lead gunshot available in Europe. By contrast, Yorkshire grouse experienced a high incidence (65.8%) of bone lead >20 microg/g. The Pb(206):Pb(207) and Pb(208):Pb(207)ratios in bones of these highly exposed birds were consistent with a combined exposure to ingested lead gunshot and lead from galena mining in the region. Lead isotope ratios also indicated that lead from UK gasoline combustion and fallout from atmospheric particles was not a likely source of elevated lead in bones of either Scottish or Yorkshire grouse. Suggested management options for the three moors include adopting nontoxic shot for all game shooting on the estates, allowing heather (Calluna vulgaris) vegetation to grow tall in lead shot fall-out zones to reduce physical access to high densities of lead shot already present, and provision of calcareous grit across moors to reduce lead assimilation from all ingested sources of lead. PMID:19264349

Thomas, Vernon G; Scheuhammer, Anton M; Bond, Della E

2009-05-15

169

Impact of unintentional selective harvesting on the population dynamics of red grouse.  

PubMed

1.?The effect of selective exploitation of certain age, stage or sex classes (e.g., trophy hunting) on population dynamics is relatively well studied in fisheries and sexually dimorphic mammals. 2.?Harvesting of terrestrial species with no morphological differences visible between the different age and sex classes (monomorphic species) is usually assumed to be nonselective because monomorphicity makes intentionally selective harvesting pointless and impractical. But harvesting of the red grouse (Lagopus lagopus scoticus), a monomorphic species, was recently shown to be unintentionally selective. This study uses a sex- and age-specific model to explore the previously unresearched effects of unintentional harvesting selectivity. 3.?We examine the effects of selectivity on red grouse dynamics by considering models with and without selectivity. Our models include territoriality and parasitism, two mechanisms known to be important for grouse dynamics. 4.?We show that the unintentional selectivity of harvesting that occurs in red grouse decreases population yield compared with unselective harvesting at high harvest rates. Selectivity also dramatically increases extinction risk at high harvest rates. 5.?Selective harvesting strengthens the 3- to 13-year red grouse population cycle, suggesting that the selectivity of harvesting is a previously unappreciated factor contributing to the cycle. 6.?The additional extinction risk introduced by harvesting selectivity provides a quantitative justification for typically implemented 20-40% harvest rates, which are below the maximum sustainable yield that could be taken, given the observed population growth rates of red grouse. 7.?This study shows the possible broad importance of investigating in future research whether unintentionally selective harvesting occurs on other species. PMID:21595686

Bunnefeld, Nils; Reuman, Daniel C; Baines, David; Milner-Gulland, E J

2011-11-01

170

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

171

Transcriptomic response of red grouse to gastro-intestinal nematode parasites and testosterone: implications for population dynamics.  

PubMed

A central issue in ecology is in understanding the relative influences of intrinsic and extrinsic effects on population regulation. Previous studies on the cyclic population dynamics of red grouse (Lagopus lagopus scoticus) have emphasized the destabilizing effects of either nematode parasites or territorial behaviour and aggression. The potential interacting effects of these processes, mediated through density-dependent, environmentally induced alterations of host immunocompetence influencing susceptibility to parasites have not been considered. Male red grouse at high density are more aggressive, associated with increased testosterone, which potentially could lead to reduced immunocompetence at a stage when parasites are most prevalent. This could depress individual condition, breeding performance and survival and thus drive or contribute to overall reductions in population size. Here, we characterize the transcriptomic response of grouse to nematode parasite infection and investigate how this is subsequently affected by testosterone, using a microarray approach contrasting red grouse with high and low parasite load at both high and low testosterone titre. A suite of 52 transcripts showed a significant level of up-regulation to either chronic parasite load or experimental parasite infection. Of these, 51 (98%) showed a reduced level of expression under conditions of high parasite load and high testosterone. The genes up-regulated by parasites and then down-regulated at high testosterone titre were not necessarily associated with immune response, as might be intuitively expected. The results are discussed in relation to the fitness and condition of individual red grouse and factors influencing the regulation of abundance in natural populations. PMID:21073676

Webster, L M I; Paterson, S; Mougeot, F; Martinez-Padilla, J; Piertney, S B

2011-03-01

172

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

173

PROTOCOLS FOR SUCCESSFUL TRANSLOCATION OF PTARMIGAN CLAIT E. BRAUN1  

E-print Network

of ptarmigan (Lagopus spp.) based on field work in Colorado and Alaska during the last four decades. Use-tailed Ptarmigan (L. leucura) in four states, and reintroduction of Evermann's Rock Ptarmigan (L. muta) to Agattu

Sandercock, Brett K.

174

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

bubo Búho Real 16 3 Buteo buteo Busardo Ratonero 75 Caprimulgus europaeus Chotacabras Gris 8 2 torquilla Torcecuello 25 3 link Lagopus mutus Lagópodo Alpino 54 + Lanius collurio Alcaudón Dorsirrojo 62 3

Carrascal, Luis M.

175

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

Mochuelo Común 24 3 Bubo bubo Búho Real 36 3 Buteo buteo Busardo Ratonero 96 Calandrella brachydactyla torquilla Torcecuello 52 3 link Lagopus mutus Lagópodo Alpino 12 + Lanius collurio Alcaudón Dorsirrojo 96 3

Carrascal, Luis M.

176

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

177

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

178

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

179

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

180

Functional and numerical responses of four lemming predators in high arctic Greenland  

E-print Network

), as the main prey of four predators: Arctic fox (Alopex lagopus), stoat (Mustela erminea), long-tailed skua the responses of the avian predators, but it has only a weak numerical response. Finally, the stoat (Mustela erminea) is the most specialized predator and the only one with a clearly delayed numerical response

Hanski, Ilkka

181

Comparative Winter Habitat Use and Associations among Herbivores in the High Arctic  

Microsoft Academic Search

We studied winter habitat use and interspecific associations among large- and medium-sized herbivores on southeastern Victoria Island, Arctic Canada, by documenting the deposition of feces in relation to vegetation. Associations between ptarmigan (Lagopus spp.), arctic hares (Lepus arcticus), caribou (Rangifer tarandus), and muskoxen (Ovibos moschatus) were assessed using the Jaccard Index (JI) and ?2 at two scales, i.e., with 1

JAMES A. SCHAEFER; SCOTT D. STEVENS; FRANÇOIS MESSIER

1996-01-01

182

Phylogenetic analyses of Coprinopsis sections Lanatuli and Atramentarii identify multiple species within morphologically defined taxa.  

PubMed

Sections Lanatuli and Atramentarii of the genus Coprinopsis contain some of the best known and most important agaric species, including C. cinerea and C. lagopus, yet a critical, phylogeny-based assessment of the species limits has not been carried out. Taxa have been characterized chiefly on the basis of morphological characters, which however show little discriminatory power and/or considerable overlap between several species pairs. We used ITS and LSU sequence data of 29 described taxa in Coprinopsis sections Lanatuli and Atramentarii to infer species limits and the correspondence between morphological characters and species lineages, as well as to examine the phylogenetic affinities of sections Lanatuli and Atramentarii. Our analyses recovered three large clades, implying a paraphyly for section Lanatuli. Based on morphology and clade structure, we estimate ca. 38 species in the two sections, including several potentially new taxa, three of which are described herein. Coprinopsis pachyderma, C. lagopus var. vacillans, C. acuminata, C. spelaiophila, Coprinus citrinovelatus and Cop. brunneistrangulatus were found to be synonymous with other, earlier described species. Congruent with previous mating studies, our analyses recovered multiple, morphologically indistinguishable lineages within C. lagopus, which included C. lagopus var. vacillans, an ephemeral, developmental variant. Morphological traits supporting the inferred clade structure are discussed. Three new taxa (C. fusispora, C. babosiae, C. villosa), and one new combination (C. mitraespora) are proposed. PMID:23074175

Nagy, László G; Desjardin, Dennis E; Vágvölgyi, Csaba; Kemp, Roger; Papp, Tamás

2013-01-01

183

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

184

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

185

The helminth fauna of birds of prey (Accipitriformes, Falconiformes and Strigiformes) in the Netherlands  

Microsoft Academic Search

Eighteen species of birds of prey in Netherlands were examined for helminth parasites: Accipitriformes - Accipiter gentilis (15 birds), A. nisus (9), Aquila pomarina (1), Buteo buteo (56), B. lagopus (4), Circaetus gallicus (2), Circus aeruginosus (2), C. cyaneus (3), Pernis apivorus (5); Falconiformes - Falco columbarius (2), F. peregrinus (2), F. subbuteo (6), F. tinnunculus (31); Strigiformes - Asio

F. H. M. Borgsteede; A. Okulewicz; P. E. F. Zoun; J. Okulewicz

2003-01-01

186

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

187

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

188

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

189

Fluctuations of observed breeding Rough-legged Hawks and Gyrfalcons: regularity reconsidered  

Microsoft Academic Search

We recently assessed regularity in fluctuation of annual numbers of breeding pairs observed for several raptor species, and found no indication of reputed regular or cyclic fluctuations in our Colville River, Alaska sample for Gyrfalcons (Falco rusticolus) or Rough-legged Hawks (Buteo lagopus) (Mindell et al. 1987). Discussions with colleagues have prompted us to expand our analysis and clarify key points.

D. P. Mindell; C. M. White

1988-01-01

190

Oral Vaccination of Captive Arctic Foxes with Lyophilized SAG2 Rabies Vaccine  

Microsoft Academic Search

Arctic foxes (Alopex lagopus) were immunized with lyophilized SAG2 oral rabies vaccine. The effectiveness of this vaccine was determined by serologic response and survival to challenge by rabies virus isolated from a red fox from Alaska (USA). No vaccine virus was found in saliva 1-72 hr after ingestion. At 2 wk after vaccination, all foxes had seroconverted, with rabies virus

Erich H. Follmann; Donald G. Ritter; Donald W. Hartbauer

191

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

192

Molecular instability induced by aluminum stress in Plantago species.  

PubMed

Aluminum (Al) is one of the most abundant metals on earth's crust and Al toxicity represents one of the major factors that limit plant growth and productivity in acid soils (with a pH?5.0). In this study the mutagenic/genotoxic effects of Al were evaluated in roots and leaves of two Plantago, species, Plantago almogravensis and Plantago lagopus, using ISSRs markers. Both species were exposed to 400 ?M Al during 7 and 21 days. Ten ISSR primers produced polymorphic bands. In P. almogravensis, a total of 257 and 258 bands in roots and 255 and 265 bands in leaves were produced in the presence and absence of Al, respectively. In P. lagopus were produced 279 and 278 a total bands in roots and 275 and 274 bands in leaves, under the same conditions. The changes in ISSR profiles after Al treatment were considered as gain and/or loss of bands compared with the controls. The results suggest that changes in genomic template stability (GTS) could be detected with ISSR profiles. This molecular marker proved to be a good tool to detect the effects of Al on DNA profiles. It seems that Al did not interfere significantly with DNA integrity in both species but generated less ISSR stability in P. almogravensis than in P. lagopus. The results confirm the tolerance of P. almogravensis and suggest the same behavior of P. lagopus. Although further studies are required for confirmation the Al tolerance behavior of P. lagopus, a potential application for phytoremediation can be also considered due its wide distribution. PMID:25344171

Correia, Sofia; Matos, Manuela; Ferreira, Vanessa; Martins, Neusa; Gonçalves, Sandra; Romano, Anabela; Pinto-Carnide, Olinda

2014-08-01

193

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

194

Historical biogeography and a mitochondrial DNA phylogeny of grouse and ptarmigan.  

PubMed

We sequenced 2690 nucleotides of mitochondrial DNA (mtDNA) including the entire control region (CR), partial 12S and 16S ribosomal RNAs, NADH dehydrogenase subunit 2, and cytochrome b genes from representatives of all the 17 living species of grouse and ptarmigan (Aves; Galliformes; subfamily Tetraoninae). Substitution rates and phylogenetic signals were variable among genes, with the CR being more informative than protein-coding and rRNA genes. Phylogenetic trees, computed with the CR or the concatenated sequences, indicate that: (1) genus Bonasa is monophyletic and basal within the subfamily, (2) all the other currently recognized genera of Tetraoninae are monophyletic, except Dendragapus; (3) D. obscurus is related to Centrocercus urophasianus and divergent from former D. canadensis and D. falcipennis, which, accordingly, may be ascribed to the distinct genus Falcipennis; (4) Tympanuchus, Dendragapus, and Centrocercus form a clade comprising taxa distributed exclusively in North America; and (5) the North American species of Bonasa (B. umbellus) and Lagopus (L. leucurus) are basal to their Eurasian and Holarctic congeneric species. These findings, and a dispersal-vicariance analysis, support a North American origin of the subfamily and of all the genera of Tetraoninae, with the possible exception of Tetrao. Present species distributions might have been attained by at least three dispersal events from North America to Eurasia, involving the ancestors to Palearctic Bonasa, the ancestors to circumpolar Lagopus mutus/L. lagopus, and the clade leading to Tetrao/Falcipennis. According to a "standard calibration" of the mtDNA molecular clock (2% sequence divergence per million years), Bonasa split about 5-6 million years ago, the other genera diverged during the upper Pliocene, and most of the congeneric species with North American and Eurasian distributions (Bonasa, Lagopus, and Falcipennis) originated during the lower Pleistocene, well before the last interruption of the Beringian land bridge. PMID:11421655

Lucchini, V; Höglund, J; Klaus, S; Swenson, J; Randi, E

2001-07-01

195

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

196

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

197

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

198

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

199

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

200

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

201

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

202

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

203

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

204

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

205

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

206

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

207

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

208

Simultaneous RP-HPLC-DAD separation, and determination of flavonoids and phenolic acids in Plantago L. species.  

PubMed

A rapid reversed-phase (RP) high-performance liquid chromatography method was developed and applied for simultaneous separation, and determination of flavonoids and phenolic acids in eight Plantago L. taxa (P. altissima L., P. argentea Chaix, P. coronopus L., P. holosteum Scop. ssp. depauperata Pilger, P. holosteum ssp. holosteum, P. holosteum ssp. scopulorum (Degen) Horvati?, P. lagopus L., and P. maritima L.) growing in Croatia. Chromatographic separation was carried out on Zorbax Eclipse XDB-C18 using gradient elution with a H2 O (pH?2.5, adjusted with CF3 COOH) and MeCN mixture at 30°. The contents of analyzed phenolic compounds (% of the dry weight of the leaves, dw) varied among examined species: rutin (max. 0.024%, P. argentea), hyperoside (max. 0.020%, P. lagopus), quercitrin (max. 0.013%, P. holosteum ssp. holosteum), quercetin (max. 0.028%, P. holosteum ssp. scopulorum), chlorogenic acid (max. 0.115%, P. lagopus), and caffeic acid (max. 0.046%, P. coronopus). Isoquercitrin was detected only in P. argentea (0.020%), while isochlorogenic acid content was below limit of quantification in all investigated species. Multivariate analyses (UPGMA and PCA) showed significant differences in contents of investigated polyphenolic compounds between different Plantago taxa. Accordingly, investigated substances might be employed as chemotaxonomic markers in the study of the complex genus Plantago. PMID:23847075

Juriši? Grubeši?, Renata; Sre?nik, Goran; Kremer, Dario; Vukovi? Rodríguez, Jadranka; Nikoli?, Toni; Vladimir-Kneževi?, Sanda

2013-07-01

209

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

210

Introduced predator removal from islands. Exxon Valdez oil spill restoration project final report  

SciTech Connect

In order to restore black oystercatchers (Haematopus bachmani) and pigeon guillemots (Cepphus columba), 2 species injured by the T/V Exxon Valdez oil spill, the introduced predator, artic fox (Alopex lagopus), was removed from 2 islands near the western edge of the trajectory of the oil. Surveys indicated that although adequate nesting habitat was available at Simeonof and Chernabura, oystercatcher and guillemot population densities were much lower than at nearby fox-free islands. Elimination of foxes is expected to dramatically increase populations of these injured species as well as other native birds.

Byrd, G.V.; Bailey, E.P.; Stahl, W.

1996-05-01

211

The microbial biosynthesis of methionine  

PubMed Central

1. The enzymes leading to the methylation of homocysteine have been examined in three micro-organisms: a cobalamin-producing bacterium, Bacillus megaterium; a yeast, Candida utilis; and a basidiomycete fungus, Coprinus lagopus. The yeast and the fungus contain negligible endogenous cobalamin. 2. Extracts of each organism catalyse C1-transfer from serine to homocysteine with a polyglutamate folate coenzyme. 3. The enzymes generating the methyl group of methionine from C-3 of serine have similar properties in each case, but different mechanisms of homocysteine transmethylation from 5-methyltetrahydrofolates were found. 4. B. megaterium contains an enzyme with properties suggestive of a vitamin B12-dependent homocysteine transmethylase, whereas Cand. utilis and Cop. lagopus transfer the methyl group by a reaction characteristic of the cobalamin-independent mechanism established for Escherichia coli. 5. The specificity of each transmethylase for a 5-methyltetrahydropteroylpolyglutamate is consistent with the results of analyses of endogenous folates in these organisms, which showed only conjugated forms. 6. None of the extracts catalysed methionine production from S-adenosylmethionine and homocysteine. 7. These results are compared with results now available for methionine synthesis in other organisms, which show a considerable diversity of mechanisms. PMID:4627687

Salem, A. R.; Foster, M. A.

1972-01-01

212

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

213

Reproductive characteristics of migratory golden eagles in Denali National Park, Alaska  

USGS Publications Warehouse

We describe reproductive characteristics of Golden Eagles (Aquila chrysaetos) breeding in Denali National Park, Alaska during an entire snowshoe hare (Lepus americanus) cycle, 1988-1997. Data on nesting eagles were collected at 58 to 72 nesting areas annually using two aerial surveys. Surveys were conducted during the incubation period to determine occupancy and nesting activities and late in the nestling period to count nestlings and determine nesting success. Annual occupancy rates of nesting areas did not vary significantly, whereas laying rates, success rates, and mean brood size varied significantly over the study period. Fledgling production for the study population varied sevenfold during the ten-year period. Laying rates, mean brood size, and overall population productivity were significantly correlated with abundance of cyclic snowshoe hare and Willow Ptarmigan (Lagopus lagopus) populations. Reproductive rates of Golden Eagles in Denali were similar to those of Golden Eagles from other high latitude study areas in North America, but lower than for Golden Eagles from temperate zone study areas in North America.

McIntyre, C.L.; Adams, L.G.

1999-01-01

214

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

215

Cospeciation and horizontal transmission of avian sarcoma and leukosis virus gag genes in galliform birds.  

PubMed

In a study of the evolution and distribution of avian retroviruses, we found avian sarcoma and leukosis virus (ASLV) gag genes in 26 species of galliform birds from North America, Central America, eastern Europe, Asia, and Africa. Nineteen of the 26 host species from whom ASLVs were sequenced were not previously known to contain ASLVs. We assessed congruence between ASLV phylogenies based on a total of 110 gag gene sequences and ASLV-host phylogenies based on mitochondrial 12S ribosomal DNA and ND2 sequences to infer coevolutionary history for ASLVs and their hosts. Widespread distribution of ASLVs among diverse, endemic galliform host species suggests an ancient association. Congruent ASLV and host phylogenies for two species of Perdix, two species of Gallus, and Lagopus lagopus and L. mutus also indicate an old association with vertical transmission and cospeciation for these ASLVs and hosts. An inference of horizontal transmission of ASLVs among some members of the Tetraoninae subfamily (grouse and ptarmigan) is supported by ASLV monophyletic groups reflecting geographic distribution and proximity of hosts rather than host species phylogeny. We provide a preliminary phylogenetic taxonomy for the new ASLVs, in which named taxa denote monophyletic groups. PMID:10756010

Dimcheff, D E; Drovetski, S V; Krishnan, M; Mindell, D P

2000-05-01

216

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

217

Cospeciation and Horizontal Transmission of Avian Sarcoma and Leukosis Virus gag Genes in Galliform Birds  

PubMed Central

In a study of the evolution and distribution of avian retroviruses, we found avian sarcoma and leukosis virus (ASLV) gag genes in 26 species of galliform birds from North America, Central America, eastern Europe, Asia, and Africa. Nineteen of the 26 host species from whom ASLVs were sequenced were not previously known to contain ASLVs. We assessed congruence between ASLV phylogenies based on a total of 110 gag gene sequences and ASLV-host phylogenies based on mitochondrial 12S ribosomal DNA and ND2 sequences to infer coevolutionary history for ASLVs and their hosts. Widespread distribution of ASLVs among diverse, endemic galliform host species suggests an ancient association. Congruent ASLV and host phylogenies for two species of Perdix, two species of Gallus, and Lagopus lagopus and L. mutus also indicate an old association with vertical transmission and cospeciation for these ASLVs and hosts. An inference of horizontal transmission of ASLVs among some members of the Tetraoninae subfamily (grouse and ptarmigan) is supported by ASLV monophyletic groups reflecting geographic distribution and proximity of hosts rather than host species phylogeny. We provide a preliminary phylogenetic taxonomy for the new ASLVs, in which named taxa denote monophyletic groups. PMID:10756010

Dimcheff, Derek E.; Drovetski, Sergei V.; Krishnan, Mallika; Mindell, David P.

2000-01-01

218

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

219

Pronounced variation in tarsal and foot feathering in the upland buzzard (Buteo hemilasius) in Mongolia  

USGS Publications Warehouse

During 1994, 1995, 1997, and 1998 expeditions across Mongolia, we located over 250 upland buzzard (Buteo hemilasius) nests. At these, we noted considerable morphological variation in plumage coloration and in leg pterylosis. In 1997 and 1998, we examined 131 nests scattered across eastern and central Mongolia and report here the tarsal condition of 119 nestlings from 59 broods where young were at least 2 weeks of age. Of 119 birds carefully examined, 50 (42%) had less than fully feathered tarsi and 4 of the 69 with fully feathered tarsi had scattered feathers on their toes. Thus, 54 of 119 birds (45%) in some way deviated from the feathered tarsibare toes condition. This extraordinary degree of variability in feather patterns may be best explained as the result of extensive and relatively recent hybridization between the longlegged (Buteo rufinus) and roughlegged (B. lagopus) buzzards and/or between long-legged and upland buzzards.

Ellis, D.H.; Woffinden, N.; Whitlock, P.L.; Tsengeg, P.

1999-01-01

220

Thermoregulation of polecat and raccoon dog: a comparative study with stoat, mink and blue fox.  

PubMed

1. Oxygen consumption (ml X kg0.75 per min) in relation to ambient temperature (Ta) in the raccoon dog (Nyctereutes procyonoides), polecat (Mustela putorius), mink (Mustela vison) and stoat (Mustela erminea) is described by equations y = 14.2 - 0.23x, y = 26.3 - 0.47x, y = 26.9 - 0.33x and y = 39.0 - 1.06x, respectively. Resting metabolic rate (RMR) of blue fox (Alopex lagopus) could be measured only at thermoneutrality. 2. In polecats, calorigenic response to noradrenaline was about 40% above the RMR, while in raccoon dogs it was absent. 3. The cooling constant (per min) of deceased raccoon dogs was similar to that measured for blue fox (0.0008), but considerably higher than that measured for dog (beagle 0.0016) or polecats (0.0023-0.0031). PMID:6131765

Korhonen, H; Harri, M; Asikainen, J

1983-01-01

221

Mapping of polar fox renal cortex proteins using two-dimensional gel electrophoresis and mass spectrometry--a preliminary study.  

PubMed

The aim of the present study was to establish protein map of polar fox (Alopex lagopus) renal cortex. Kidney cortex proteins of isoelectric point ranging from 3 to 10 were analysed using two-dimensional electrophoresis and MALDI-TOF mass spectrometry. Sixteen protein spots corresponding to thirteen different gene products were identified. These proteins were divided into following groups: lipid and fatty acid metabolism, amino acid metabolism, energetic pathways, regulatory proteins, transport proteins and structural proteins. This is the first attempt to create reproducible 2-D map, of renal cortex proteins characteristic for polar foxes, used as animal model for carnivores. It is worth emphasizing that the results of this study may broaden currently available protein databases. PMID:24988848

Ciechanowicz, A K; Ozgo, M; Sta?ski, ? R; Herosimczyk, A; Piotrowska, A; Szymeczko, R; Laszczy?ska, M; Skrzypczak, W F

2014-01-01

222

Prevalence of Toxoplasma gondii infection diagnosed by PCR in farmed red foxes, arctic foxes and raccoon dogs.  

PubMed

The aim of this study was to compare Toxoplasma gondii infection in three canid species: red fox Vulpes vulpes, arctic fox Vulpes lagopus and raccoon dog Nyctereutesprocyonoides kept at the same farm. Anal swabs were taken from 24 adult and 10 juvenile red foxes, 12 adult arctic foxes, three adult and seven juvenile raccoon dogs. Additionally, muscle samples were taken from 10 juvenile red foxes. PCR was used to detect T. gondii DNA. T. gondii infection was not detected in any of the arctic foxes; 60% ofraccoon dogs were infected; the prevalence of the parasite in material from red fox swabs was intermediate between the prevalence observed in arctic foxes and raccoon dogs. It is possible that susceptibility and immune response to the parasite differ between the three investigated canid species. T. gondii DNA was detected in muscle tissue of five young foxes. The results of this study suggest that T. gondii infection is not rare in farmed canids. PMID:22428309

Górecki, Marcin Tadeusz; Galbas, Mariola; Szwed, Katarzyna; Przysiecki, Piotr; Dullin, Piotr; Nowicki, S?awomir

2012-01-01

223

Morphological, histochemical and immunohistochemical studies of polar fox kidney.  

PubMed

The aim of the present study was to evaluate the morphology and intermediate filaments cytokeratin, desmin and vimentin expression in the kidneys of the polar fox (Alopex lagopus). Routine morphological, histochemical and immunohistochemical techniques of examinations of the kidneys of adult male and female polar foxes were used. We found different localizations and different levels of immunoexpression of cytokeratin in epithelia of calyxes, distal tubules and Henle's loops, and also in endothelial cells. We also noted immunolocalization and immunoexpression of vimentin in mesangial cells, interstitial tissue and distal tubules. Desmin reactivity was revealed for muscle cells of arteries and mesangial cells. Our study is the first attempt to localize cytoskeletal intermediate filaments performed on polar fox kidneys. It is worth noting that our observations concerning the distribution of vimentin in the polar fox kidney may suggest that protein as being useful as a marker of distal tubules in the polar fox kidney. PMID:22532141

Laszczy?ska, Maria; O?go, Ma?gorzata; Szymeczko, Roman; Wylot, Marcin; S?uczanowska-G??bowska, Sylwia; Piotrowska, Katarzyna; Skrzypczak, Wies?aw

2012-01-01

224

Understanding sex differences in the cost of terrestrial locomotion.  

PubMed

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

2012-02-22

225

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

226

[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

227

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

228

Prevalence of Rabies Virus in Foxes Trapped in the Canadian Arctic  

PubMed Central

Brains and salivary glands of 521 trapped arctic foxes (Alopex lagopus) submitted from four different settlement areas in the Northwest Territories were examined for rabies by the standard fluorescent antibody and mouse inoculation tests. Rabies antigen was present in 44 of 201 (21.9%) brains from foxes trapped in the Sachs Harbour area, but submissions from Cambridge Bay (127), Spence Bay (93) and Gjoa Haven (100) were negative. Virus was also present in salivary glands from 43 (97.7%) of these 44 positive foxes. The arctic fox continues to be the main wildlife reservoir of rabies in the Canadian Arctic and foxes in the prodromal stage of the disease pose a particular threat to the trapper. Preexposure vaccination should always be a consideration in this occupational group. PMID:7459793

Secord, D. C.; Bradley, J. A.; Eaton, R. D.; Mitchell, D.

1980-01-01

229

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

230

Cadmium toxicity among wildlife in the Colorado Rocky Mountains  

USGS Publications Warehouse

Cadmium is known to be both extremely toxic and ubiquitous in natural environments. It occurs in almost all soils, surface waters and plants, and it is readily mobilized by human activities such as mining. As a result, cadmium has been named as a potential health threat to wildlife species; however, because it exists most commonly in the environment as a trace constituent, reported incidences of cadmium toxicity are rare. Here we have measured trace metals in the food web and tissues of white-tailed ptarmigan (Lagopus leucurus) in Colorado. Our results suggest that cadmium toxicity may be more common among natural populations of vertebrates than has been appreciated to date and that cadmium toxicity may often go undetected or unrecognized. In addition, our research shows that ingestion of even trace quantities of cadmium can influence not only the physiology and health of individual organisms, but also the demographics and the distribution of species.

Larison, J.R.; Likens, G.E.; Fitzpatrick, J.W.; Crock, J.G.

2000-01-01

231

Comparative tissue distribution of metals in birds in Sweden using ICP-MS and laser ablation ICP-MS.  

PubMed

Cadmium, copper, lead, palladium, platinum, rhodium, and zinc profiles were investigated along feather shafts of raptor and other bird species by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The distribution of external versus internal metal contamination of feathers was investigated. The species examined were peregrine falcon (Falco peregrinus), sparrowhawk ( Accipiter nisus), willow grouse (Lagopus lagopus), and house sparrow (Passer domesticus) in Sweden. For habitat comparisons, total Cu, Pb, Zn, and Cd concentrations were analyzed by ICP-MS in feathers of the examined species as well as captive peregrine falcon. For investigation of metal distribution and correlation in different biological materials of raptors, total concentrations of Cu, Pb, Cd, and Zn were also investigated by ICP-MS in feathers, eggs, blood, feces, liver, and kidney of wild peregrine falcon from southwestern Sweden. Laser ablation of feathers revealed that Pb contamination is both external and internal, Zn contamination is internal, and Cd and Cu contamination is predominantly internal, with a few externally attached particles of high concentration. Pb, Cu, and Cd signal intensities were highest in urban habitats and contamination was mainly external in feathers. The background signal intensity of Zn was also higher in birds from urban habitats. The laser ablation profile of PGE (Pt, Pd, Rh) demonstrated that PGE contamination of feathers consists almost exclusively of externally attached PGE-containing particles, with little evidence of internally deposited PGE.Generally, total metal concentrations in feathers were highest in sparrowhawk and house sparrow due to their urban habitat. Total Cu, Zn, and Cd concentrations were highest in liver and kidney due to binding to metallothionein, while the total Pb concentration was highest in feces due to the high excretion rate of Pb. A decreasing temporal trend for Pb in feathers, showing that Pb levels in feathers have decreased since the introduction of nonleaded petrol, is also discussed. PMID:15386152

Ek, Kristine H; Morrison, Gregory M; Lindberg, Peter; Rauch, Sébastien

2004-08-01

232

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

233

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. PMID:25065712

Shoemaker, Kevin T; Akçakaya, H Resit

2015-02-01

234

Demographic consequences of age-structure in extreme environments: population models for arctic and alpine ptarmigan.  

PubMed

Organisms living in arctic and alpine environments are increasingly impacted by human activities. To evaluate the potential impacts of global change, a better understanding of the demography of organisms in extreme environments is needed. In this study, we compare the age-specific demography of willow ptarmigan (Lagopus lagopus) breeding at arctic and subalpine sites, and white-tailed ptarmigan (L. leucurus) breeding at an alpine site. Rates of egg production improved with age at the alpine and subalpine sites, but the stochastic effects of nest and brood predation led to similar rates of annual fecundity among 1-, 2-, and 3+-year-old females. All populations had short generation times (T<2.7 years) and low net reproductive rates (R0<1.2). Stable age distributions were weighted towards 1-year-old females in willow ptarmigan (>59%), and to 3+-year-old females in white-tailed ptarmigan (>47%). High damping ratios (rho>3.2) indicated that asymptotic estimates were likely to match natural age distributions. Sensitivity and elasticity values indicated that changes in juvenile survival would have the greatest impact on the finite rate of population change (lambda) in willow ptarmigan, whereas changes to the survival of 3+-year-old females would have a greater effect in white-tailed ptarmigan. High survivorship buffers white-tailed ptarmigan in alpine environments against the potential effects of climate change on annual fecundity, but may make the species more sensitive to the effects of pollutants or harvesting on adult survival. Conversely, processes that reduce annual fecundity would have a greater impact on the population viability of willow ptarmigan in arctic and subalpine environments. If these same demographic patterns prove to be widespread among organisms in extreme environments, it may be possible to develop general recommendations for conservation of the biological resources of arctic and alpine ecosystems. PMID:16010534

Sandercock, Brett K; Martin, Kathy; Hannon, Susan J

2005-11-01

235

A note on the reproductive success of primiparous blue fox vixens in social groups.  

PubMed

Our aim was to compare traditional breeding system, i.e. artificial insemination with singly-housing, to alternative breeding systems in farmed blue fox (Alopex lagopus or Vulpes lagopus) vixens. At the age of 7 weeks (i.e. at weaning), 48 randomly selected female blue fox cubs were divided into four experimental groups: (1) artificially inseminated singly-housed vixens in cages (AI-SC), (2) artificially inseminated pair-housed vixens in double-cages (AI-PC), (3) naturally bred pair-housed vixens with a male in triple-cages (NB-PC), and (4) naturally bred pair-housed vixens with a male in outdoor enclosures (NB-PE). The cubs were counted on days 1, 2, 3, 7, 14 and 49 postpartum and the reproductive performance per breeding (RPB) and per mated vixens (RPM) with its subcomponents were formed from these data. RPB was zero in both NB groups. In AI-PC and AI-SC, RPB was 1.3+/-2.5 and 4.1+/-4.7 cubs, respectively. RPB and the percentage of vixens that weaned cubs were lower in NB-PC and NB-PE than in AI-PC. In AI groups, both RPB and RPM at weaning tended to be better in singly-housed than in pair-housed blue fox vixens. No statistically significant differences were found between AI groups in the percentage of vixens without oestrus, barren vixens, vixens that lost all cubs or weaned at least one cub. Only in one pair (AI-PC) both vixens displayed communal breeding and weaned cubs. The present results show that vixens in traditional breeding system had better RPM than in any of the studied pair-housing systems. The current blue fox population has been effectively selected for cage-breeding and artificial reproduction, and therefore blue foxes generally reproduce well with artificial insemination after careful detection of oestrus in traditional breeding conditions. PMID:18602229

Pyykönen, T; Ahola, L; Hänninen, S; Mononen, J

2009-06-01

236

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

237

Digging for gold nuggets: uncovering novel candidate genes for variation in gastrointestinal nematode burden in a wild bird species.  

PubMed

The extent to which genotypic variation at a priori identified candidate genes can explain variation in complex phenotypes is a major debate in evolutionary biology. Whereas some high-profile genes such as the MHC or MC1R clearly do account for variation in ecologically relevant characters, many complex phenotypes such as response to parasite infection may well be underpinned by a large number of genes, each of small and effectively undetectable effect. Here, we characterize a suite of novel candidate genes for variation in gastrointestinal nematode (Trichostrongylus tenuis) burden among red grouse (Lagopus lagopus scotica) individuals across a network of moors in north-east Scotland. We test for associations between parasite load and genotypic variation in twelve genes previously identified to be differentially expressed in experimentally infected red grouse or genetically differentiated among red grouse populations with overall different parasite loads. These genes are associated with a broad physiological response including immune system processes. Based on individual-level generalized linear models, genotypic variants in nine genes were significantly associated with parasite load, with effect sizes accounting for differences of 514-666 worms per bird. All but one of these variants were synonymous or untranslated, suggesting that these may be linked to protein-coding variants or affect regulatory processes. In contrast, population-level analyses revealed few and inconsistent associations with parasite load, and little evidence of signatures of natural selection. We discuss the broader significance of these contrasting results in the context of the utility of population genomics and landscape genomics approaches in detecting adaptive genomic signatures. PMID:25752450

Wenzel, M A; Piertney, S B

2015-04-01

238

Herbivores influence the growth, reproduction, and morphology of a widespread Arctic willow.  

PubMed

Shrubs have expanded in Arctic ecosystems over the past century, resulting in significant changes to albedo, ecosystem function, and plant community composition. Willow and rock ptarmigan (Lagopus lagopus, L. muta) and moose (Alces alces) extensively browse Arctic shrubs, and may influence their architecture, growth, and reproduction. Furthermore, these herbivores may alter forage plants in such a way as to increase the quantity and accessibility of their own food source. We estimated the effect of winter browsing by ptarmigan and moose on an abundant, early-successional willow (Salix alaxensis) in northern Alaska by comparing browsed to unbrowsed branches. Ptarmigan browsed 82-89% of willows and removed 30-39% of buds, depending on study area and year. Moose browsed 17-44% of willows and browsed 39-55% of shoots. Browsing inhibited apical dominance and activated axillary and adventitious buds to produce new vegetative shoots. Ptarmigan- and moose-browsed willow branches produced twice the volume of shoot growth but significantly fewer catkins the following summer compared with unbrowsed willow branches. Shoots on browsed willows were larger and produced 40-60% more buds compared to unbrowsed shoots. This process of shoot production at basal parts of the branch is the mechanism by which willows develop a highly complex "broomed" architecture after several years of browsing. Broomed willows were shorter and more likely to be re-browsed by ptarmigan, but not moose. Ptarmigan likely benefit from the greater quantity and accessibility of buds on previously browsed willows and may increase the carrying capacity of their own habitat. Despite the observed tolerance of willows to browsing, their vertical growth and reproduction were strongly inhibited by moose and ptarmigan. Browsing by these herbivores therefore needs to be considered in future models of shrub expansion in the Arctic. PMID:25047582

Christie, Katie S; Ruess, Roger W; Lindberg, Mark S; Mulder, Christa P

2014-01-01

239

Territory occupancy rate of goshawk and gyrfalcon: no evidence of delayed numerical response to grouse numbers.  

PubMed

Two recent studies on territory occupancy rates of goshawk Accipiter gentilis and gyrfalcon Falco rusticolus report a 2-3-year-delayed numerical response to grouse numbers, which is a requirement for a hypothesis of predator-generated grouse cycles. The time lags were assumed to reflect the average age of sexual maturity in the raptor species. In southern Norway, however, subadult (two-year-old) goshawk hens occupied only 18-25% of territories where occupancy was not recorded in the preceding year, and there was no significant relationship between the proportion of subadults among recruits and grouse indices two years earlier. We argue that territory occupancy rates are not appropriate indices of total raptor population levels, but rather reflect the proportion of territorial pairs that attempt to nest. Because this depends on the body condition of the hens, fluctuations in other important winter resident prey species (most important for the goshawk) and winter weather (most important for the gyrfalcon) should also be addressed. During 1988-2006, the annual proportion of goshawk territories with recorded nesting attempts in southern Norway was most closely related to the preceding autumn's population indices of black grouse Tetrao tetrix and mountain hare Lepus timidus, whereas the annual proportion of gyrfalcon territories with observations of falcons or with confirmed breeding attempts in central Norway were best explained by population indices of willow grouse Lagopus lagopus and ptarmigan L. mutus from the previous autumn, and by December temperatures. Hence, our studies do not support the predation hypothesis for grouse cycles. PMID:17549523

Selås, Vidar; Kålås, John Atle

2007-09-01

240

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

PubMed

In patchy habitats, the relationship between animal abundance and cover of a preferred habitat may change with the availability of that habitat, resulting in a functional response in habitat use. Here, we investigate the relationship of two specialized herbivores, willow ptarmigan (Lagopus lagopus) and mountain hare (Lepus timidus), to willows (Salix spp.) in three regions of the shrub tundra zone-northern Norway, northern European Russia and western Siberia. Shrub tundra is a naturally patchy habitat where willow thickets represent a major structural element and are important for herbivores both as food and shelter. Habitat use was quantified using feces counts in a hierarchical spatial design and related to several measures of willow thicket configuration. We document a functional response in the use of willow thickets by ptarmigan, but not by hares. For hares, whose range extends into forested regions, occurrence increased overall with willow cover. The occurrence of willow ptarmigan showed a strong positive relationship to willow cover and a negative relationship to thicket fragmentation in the region with lowest willow cover at landscape scale, where willow growth may be limited by reindeer browsing. In regions with higher cover, in contrast, such relationships were not observed. Differences in predator communities among the regions may contribute to the observed pattern, enhancing the need for cover where willow thickets are scarce. Such region-specific relationships reflecting regional characteristics of the ecosystem highlight the importance of large-scale investigations to understand the relationships of habitat availability and use, which is a critical issue considering that habitat availability changes quickly with climate change and human impact. PMID:21833646

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

2012-01-01

241

Herbivores Influence the Growth, Reproduction, and Morphology of a Widespread Arctic Willow  

PubMed Central

Shrubs have expanded in Arctic ecosystems over the past century, resulting in significant changes to albedo, ecosystem function, and plant community composition. Willow and rock ptarmigan (Lagopus lagopus, L. muta) and moose (Alces alces) extensively browse Arctic shrubs, and may influence their architecture, growth, and reproduction. Furthermore, these herbivores may alter forage plants in such a way as to increase the quantity and accessibility of their own food source. We estimated the effect of winter browsing by ptarmigan and moose on an abundant, early-successional willow (Salix alaxensis) in northern Alaska by comparing browsed to unbrowsed branches. Ptarmigan browsed 82–89% of willows and removed 30–39% of buds, depending on study area and year. Moose browsed 17–44% of willows and browsed 39–55% of shoots. Browsing inhibited apical dominance and activated axillary and adventitious buds to produce new vegetative shoots. Ptarmigan- and moose-browsed willow branches produced twice the volume of shoot growth but significantly fewer catkins the following summer compared with unbrowsed willow branches. Shoots on browsed willows were larger and produced 40–60% more buds compared to unbrowsed shoots. This process of shoot production at basal parts of the branch is the mechanism by which willows develop a highly complex “broomed” architecture after several years of browsing. Broomed willows were shorter and more likely to be re-browsed by ptarmigan, but not moose. Ptarmigan likely benefit from the greater quantity and accessibility of buds on previously browsed willows and may increase the carrying capacity of their own habitat. Despite the observed tolerance of willows to browsing, their vertical growth and reproduction were strongly inhibited by moose and ptarmigan. Browsing by these herbivores therefore needs to be considered in future models of shrub expansion in the Arctic. PMID:25047582

Christie, Katie S.; Ruess, Roger W.; Lindberg, Mark S.; Mulder, Christa P.

2014-01-01

242

Vegetation management with fire modifies peatland soil thermal regime.  

PubMed

Vegetation removal with fire can alter the thermal regime of the land surface, leading to significant changes in biogeochemistry (e.g. carbon cycling) and soil hydrology. In the UK, large expanses of carbon-rich upland environments are managed to encourage increased abundance of red grouse (Lagopus lagopus scotica) by rotational burning of shrub vegetation. To date, though, there has not been any consideration of whether prescribed vegetation burning on peatlands modifies the thermal regime of the soil mass in the years after fire. In this study thermal regime was monitored across 12 burned peatland soil plots over an 18-month period, with the aim of (i) quantifying thermal dynamics between burned plots of different ages (from <2 to 15 + years post burning), and (ii) developing statistical models to determine the magnitude of thermal change caused by vegetation management. Compared to plots burned 15 + years previously, plots recently burned (<2-4 years) showed higher mean, maximum and range of soil temperatures, and lower minima. Statistical models (generalised least square regression) were developed to predict daily mean and maximum soil temperature in plots burned 15 + years prior to the study. These models were then applied to predict temperatures of plots burned 2, 4 and 7 years previously, with significant deviations from predicted temperatures illustrating the magnitude of burn management effects. Temperatures measured in soil plots burned <2 years previously showed significant statistical disturbances from model predictions, reaching +6.2 °C for daily mean temperatures and +19.6 °C for daily maxima. Soil temperatures in plots burnt 7 years previously were most similar to plots burned 15 + years ago indicating the potential for soil temperatures to recover as vegetation regrows. Our findings that prescribed peatland vegetation burning alters soil thermal regime should provide an impetus for further research to understand the consequences of thermal regime change for carbon processing and release, and hydrological processes, in these peatlands. PMID:25728915

Brown, Lee E; Palmer, Sheila M; Johnston, Kerrylyn; Holden, Joseph

2015-05-01

243

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

244

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

245

Arctic foxes, lemmings, and canada goose nest survival at cape Churchill, Manitoba  

USGS Publications Warehouse

We examined factors influencing Canada Goose (Branta canadensis interior) annual nest success, including the relative abundance of collared lemmings (Dicrostonyx richardsoni), arctic fox (Alopex lagopus) den occupancy, nest density, and spring phenology using data collected during annual Canada Goose breeding area surveys at Cape Churchill, Manitoba. Nest density and arctic fox den occupancy strongly influenced Canada Goose nest success. High nest density resulted in higher nest success and high den occupancy reduced nest success. Nest success was not influenced by lemming abundance in the current or previous year as predicted by the "bird-lemming" hypothesis. Reducing arctic fox abundance through targeted management increased nest survival of Canada Geese; a result that further emphasizes the importance of arctic fox as nest predators in this system. The spatial distribution of nest predators, at least for dispersed-nesting geese, may be most important for nest survival, regardless of the abundance of small mammals in the local ecosystem. Further understanding of the factors influencing the magnitude and variance in arctic fox abundance in this region, and the spatial scale at which these factors are realized, is necessary to fully explain predator-prey-alternative prey dynamics in this system. ?? 2011 by the Wilson Ornithological Society.

Reiter, M.E.; Andersen, D.E.

2011-01-01

246

Ancient DNA reveals lack of postglacial habitat tracking in the arctic fox.  

PubMed

How species respond to an increased availability of habitat, for example at the end of the last glaciation, has been well established. In contrast, little is known about the opposite process, when the amount of habitat decreases. The hypothesis of habitat tracking predicts that species should be able to track both increases and decreases in habitat availability. The alternative hypothesis is that populations outside refugia become extinct during periods of unsuitable climate. To test these hypotheses, we used ancient DNA techniques to examine genetic variation in the arctic fox (Alopex lagopus) through an expansion/contraction cycle. The results show that the arctic fox in midlatitude Europe became extinct at the end of the Pleistocene and did not track the habitat when it shifted to the north. Instead, a high genetic similarity between the extant populations in Scandinavia and Siberia suggests an eastern origin for the Scandinavian population at the end of the last glaciation. These results provide new insights into how species respond to climate change, since they suggest that populations are unable to track decreases in habitat avaliability. This implies that arctic species may be particularly vulnerable to increases in global temperatures. PMID:17420452

Dalén, Love; Nyström, Veronica; Valdiosera, Cristina; Germonpré, Mietje; Sablin, Mikhail; Turner, Elaine; Angerbjörn, Anders; Arsuaga, Juan Luis; Götherström, Anders

2007-04-17

247

Organization of Enzymes in the Common Aromatic Synthetic Pathway: Evidence for Aggregation in Fungi  

PubMed Central

Centrifugation in sucrose density gradients of partially purified extracts from six species of fungi, i.e., Rhizopus stolonifer, Phycomyces nitens, Absidia glauca (Phycomycetes), Aspergillus nidulans (Ascomycetes), Coprinus lagopus, and Ustilago maydis (Basidiomycetes), indicate that the five enzymes catalyzing steps two to six in the prechorismic acid part of the polyaromatic synthetic pathway sediment together. The sedimentation coefficients for these enzymes are very similar in the six species and are comparable to those previously observed for the multienzyme complexes (arom aggregates) of Neurospora crassa and Saccharomyces cerevisiae. These results are interpreted as indicating the presence in each of these fungi of arom aggregates, presumably encoded by arom gene clusters similar to those in N. crassa and S. cerevisiae. Evidence has also been obtained for the presence in two species (A. nidulans and U. maydis) and the absence in the other four species of a second dehydroquinase isozyme which is distinguishable from the synthetic activity on the basis of both thermostability tests and S values. This second dehydroquinase, which is apparently involved in the catabolism of quinic acid via a pathway similar to that in N. crassa, is inducible in A. nidulans (as it is in N. crassa), but constitutive in U. maydis. These comparative findings are discussed in relation to the organization, evolution, and possible functional relationships of synthetic and catabolic aromatic pathways in fungi. PMID:5802608

Ahmed, S. I.; Giles, Norman H.

1969-01-01

248

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

249

Behavioral interactions of penned red and arctic foxes  

USGS Publications Warehouse

Expansion of the geographical distribution of red foxes (Vulpes vulpes) into the far north tundra region may lead to competition between arctic (Alopex lagopus) and red foxes for space and resources. Behavioral interactions between red and arctic foxes were evaluated during 9 trials conducted in a 4.05-ha enclosure near Woodworth, North Dakota. Each trial consisted of introducing a male-female pair of arctic foxes into the enclosure and allowing them to acclimate for approximately a week before releasing a female red fox into the enclosure, followed by her mate a few days later. In 8 of 9 trials, red foxes were dominant over arctic foxes during encounters. Activity of the arctic foxes decreased upon addition of red foxes. Arctic foxes tried unsuccessfully to defend preferred den, resting, and feeding areas. Even though the outcome of competition between red and arctic foxes in the Arctic is uncertain, the more aggressive red fox can dominate arctic foxes in direct competition for den sites and other limited resources.

Rudzinski, D.R.; Graves, H.B.; Sargeant, A.B.; Storm, G.L.

1982-01-01

250

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. PMID:25685838

Dhar, M. K.

2015-01-01

251

Structural determinants of maximal O2 transport in muscles of exercising foxes.  

PubMed

The arctic blue fox (Alopex lagopus) has a specific maximal oxygen consumption (VO2 max/Mb = 3.6 ml O2.s-1.kg-1) that is approximately 1.6-fold greater than those of dogs and horses. The fox has one of the highest body mass specific skeletal muscle mitochondrial volumes (V(mt,m)/Mb = 44 cm3.kg-1) among mammalian athletic species matching its higher VO2 max/Mb. The structural components related to capillaries, such as specific capillary length density (J(c)/Mb = 348 km.kg-1) and specific capillary volume (V(c)/Mb = 4.8 ml.kg-1), are not greater in the fox than in the larger athletes. Because a greater specific muscle diffusing capacity for oxygen (DTO2/Mb) is not utilized by the fox to achieve a higher VO2 max/Mb, a higher pressure difference for diffusion in the muscle capillaries is the alternative explanation for the fox's higher VO2 max/Mb. This mechanism is suggested by the fox's higher arterial and mixed venous capillary PO2 (120 mm Hg and 37 mm Hg, respectively) and its shorter mean muscle capillary transit time for blood (tc = 0.28 sec) compared to larger species. PMID:8738900

Bicudo, J E; Longworth, K E; Jones, J H; Taylor, C R; Hoppeler, H

1996-03-01

252

Surgical embryo transfer resulted in birth of live offspring in farmed blue fox.  

PubMed

Finland blue fox (Alopex lagopus) has great reputation in pelt industry around the world for its large size and top-ranking fur quality; however, both the herd size and the average survival rate of purebred offspring are rather low in production systems in China. Surgical transfer of blue fox embryos was investigated as a means to increase the population fox and also as a possible means to conserve endangered canine species. The animals were chosen on the basis of synchrony in natural oestrus. During the reproductive season of blue fox, 59 embryos were flushed from 6 farmed donors 9-11 days after the first insemination, and 53 embryos were transferred surgically into the uteri of the 6 paired recipients with natural synchronized oestrous. Two of the recipients littered 46-49 days after embryo transfer; one gave birth to 7 pups and the other 1 pup. This report describes the first successful embryo transfer in the farmed blue fox in China. PMID:18262370

Liu, Guo-Shi; Zhou, Guang-Bin; Zhang, Hong-Hai; Ma, Cheng-Bao; Shi, Wen-Qing; Zhu, Shi-En; Yang, Zhong-Qiang; Kang, Jian; Jia, Li-Ling; Zeng, Shen-Ming; Tian, Jian-Hui; Wang, Fen

2008-05-01

253

Heterochromatin composition and nucleolus organizer activity in four canid species.  

PubMed

Sequential staining with a counterstain-contrasted fluorescent banding technique (chromomycin A3-distamycin A-DAPI) revealed the occurrence of distamycin A-4,6-diamidino-2-phenylindole (DA-DAPI) staining heterochromatin in the centromeric regions of chromosomes 33, 36, 37, and 38 in the wolf (Canis lupus pallipes) and of chromosomes 13, 16, and 23 in the blue fox (Alopex lagopus). The red fox (Vulpes vulpes) lacked such regions. Staining with DAPI--actinomycin D produced a QFH-type banding pattern with clearcut differences in the staining behaviour of DA-DAPI positive regions between these three canid species. Staining with the fluorochrome D 287/170 did not preferentially highlight any of the DA-DAPI positive regions in any of them. Counterstain-enhanced chromomycin A3 R-banding and studies of nucleolus organizer region location and activity confirmed a close relationship between the karyotype of the wolf and the domestic dog. Few heterochromatic marker bands were encountered in these two species, but heterochromatin polymorphism was evident in the blue fox. PMID:3801970

Mayr, B; Geber, G; Auer, H; Kalat, M; Schleger, W

1986-10-01

254

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

PubMed

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 in pulses of "lemming fox" movement across the Arctic sea ice and immigration into coastal habitats in search for food. These pulses can influence the genetic structure of the receiving population. We have tested the impact of immigration on the genetic structure of the "coastal fox" population in Svalbard by recording microsatellite variation in seven loci for 162 Arctic foxes sampled during the summer and winter over a 5-year period. Genetic heterogeneity and temporal genetic shifts, as inferred by STRUCTURE simulations and deviations from Hardy-Weinberg proportions, respectively, were recorded. Maximum likelihood estimates of movement as well as STRUCTURE simulations suggested that both immigration and genetic mixture are higher in Svalbard than in the neighbouring "lemming fox" populations. The STRUCTURE simulations and AMOVA revealed there are differences in genetic composition of the population between summer and winter seasons, indicating that immigrants are not present in the reproductive portion of the Svalbard population. Based on these results, we conclude that Arctic fox population structure varies with time and is influenced by immigration from neighbouring populations. The lemming cycle is likely an important factor shaping Arctic fox movement across sea ice and the subsequent population genetic structure, but is also likely to influence local adaptation to the coastal habitat and the prevalence of diseases. PMID:21344255

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

2011-08-01

255

Reproductive characteristics of migratory golden eagles in Denali National Park, Alaska  

USGS Publications Warehouse

We describe reproductive characteristics of Golden Eagles (Aquila chrysaetos) breeding in Denali National Park, Alaska during an entire snowshoe hare( Lepus americanus) cycle, 1988-1997. Data on nesting eagles were collected at 58 to 72 nesting areas annually using two aerial surveys. Surveys were conducted during the incubation period to determine occupancy and nesting activities and late in the nestling period to count nestlings and determine nesting success. Annual occupancy rates of nesting areas did not vary significantly, whereas laying rates, success rates, and mean brood size varied significantly over the study period. Fledgling production for the study population varied sevenfold during the ten-year period. Laying rates, mean brood size, and overall population productivity were significantly correlated with abundance of cyclic snowshoe hare and Willow Ptarmigan (Lugopus lagopus) populations. Reproductive rates of Golden Eagles in Denali were similar to those of Golden Eagles from other high latitude study areas in North America, but lower than for Golden Eagles from temperate zone study areas in North America.

McIntyre, Carol L.; Adams, Layne G.

1999-01-01

256

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

257

Depredation of common eider, Somateria mollissima, nests on a central Beaufort Sea barrier island: A case where no one wins  

USGS Publications Warehouse

Along the central Beaufort Sea, Pacific Common Eiders (Somateria mollissima v-nigra) nest on unvegetated, barrier islands; often near nesting Glaucous Gulls (Larus hyperboreus). Nest-site choice likely reflects a strategy of predator avoidance: nesting on islands to avoid mammalian predators and near territorial gulls to avoid other avian predators. We observed a nesting colony of Common Eiders from first nest initiation through nesting termination on Egg Island near Prudhoe Bay, Alaska (2002 - 2003). Resident gulls depredated many eider nests, mostly during initiation. All nests failed when an Arctic Fox (Alopex lagopus) visited the island and flushed hens from their nests, exposing the eggs to depredation by the fox and gulls (resident and non-resident). Common Eiders actively defended nests from gulls, but not from foxes. Likely all three species (i.e., eiders, gulls, and foxes) ultimately achieved negligible benefit from their nest-site selection or predatory activity: (a) island nesting provided no safety from mammalian predators for eiders or gulls, (b) for Common Eiders, nesting near gulls increased egg loss, (c) for Glaucous Gulls, nesting near colonial eiders may have reduced nest success by attracting the fox, and (d) for Arctic Foxes, the depredation was of questionable value, as most eggs were cached and probably not recoverable (due to damage from fall storms). Thus, the predator-prey interactions we observed appear to be a case where little or no fitness advantage was realized by any of the species involved.

Reed, J.A.; Lacroix, D.L.; Flint, P.L.

2007-01-01

258

Habitat selection, reproduction and predation of wintering lemmings in the Arctic.  

PubMed

Snow cover has dramatic effects on the structure and functioning of Arctic ecosystems in winter. In the tundra, the subnivean space is the primary habitat of wintering small mammals and may be critical for their survival and reproduction. We have investigated the effects of snow cover and habitat features on the distributions of collared lemming (Dicrostonyx groenlandicus) and brown lemming (Lemmus trimucronatus) winter nests, as well as on their probabilities of reproduction and predation by stoats (Mustela erminea) and arctic foxes (Vulpes lagopus). We sampled 193 lemming winter nests and measured habitat features at all of these nests and at random sites at two spatial scales. We also monitored overwinter ground temperature at a subsample of nest and random sites. Our results demonstrate that nests were primarily located in areas with high micro-topography heterogeneity, steep slopes, deep snow cover providing thermal protection (reduced daily temperature fluctuations) and a high abundance of mosses. The probability of reproduction increased in collared lemming nests at low elevation and in brown lemming nests with high availability of some graminoid species. The probability of predation by stoats was density dependent and was higher in nests used by collared lemmings. Snow cover did not affect the probability of predation of lemming nests by stoats, but deep snow cover limited predation attempts by arctic foxes. We conclude that snow cover plays a key role in the spatial structure of wintering lemming populations and potentially in their population dynamics in the Arctic. PMID:21701915

Duchesne, David; Gauthier, Gilles; Berteaux, Dominique

2011-12-01

259

A comparative analysis of MC4R gene sequence, polymorphism, and chromosomal localization in Chinese raccoon dog and Arctic fox.  

PubMed

Numerous mutations of the human melanocortin receptor type 4 (MC4R) gene are responsible for monogenic obesity, and some of them appear to be associated with predisposition or resistance to polygenic obesity. Thus, this gene is considered a functional candidate for fat tissue accumulation and body weight in domestic mammals. The aim of the study was comparative analysis of chromosome localization, nucleotide sequence, and polymorphism of the MC4R gene in two farmed species of the Canidae family, namely the Chinese raccoon dog (Nycterutes procyonoides procyonoides) and the arctic fox (Alopex lagopus). The whole coding sequence, including fragments of 3'UTR and 5'UTR, shows 89% similarity between the arctic fox (1276 bp) and Chinese raccoon dog (1213 bp). Altogether, 30 farmed Chinese raccoon dogs and 30 farmed arctic foxes were searched for polymorphisms. In the Chinese raccoon dog, only one silent substitution in the coding sequence was identified; whereas in the arctic fox, four InDels and two single-nucleotide polymorphisms (SNPs) in the 5'UTR and six silent SNPs in the exon were found. The studied gene was mapped by FISH to the Chinese raccoon dog chromosome 9 (NPP9q1.2) and arctic fox chromosome 24 (ALA24q1.2-1.3). The obtained results are discussed in terms of genome evolution of species belonging to the family Canidae and their potential use in animal breeding. PMID:22047079

Skorczyk, Anna; Flisikowski, Krzysztof; Switonski, Marek

2012-05-01

260

Spatial and temporal variability of nitrogen oxide and methane fluxes from a fertilized tree plantation in Costa Rica  

NASA Astrophysics Data System (ADS)

Nitric oxide (NO), nitrous oxide (N2O), and methane (CH4) are naturally produced and consumed by soil biogeochemical processes. Naturally high variation between trace gas fluxes may temporarily increase due to agricultural management. We studied spatial and temporal variability of fluxes in the context of a 3-year field experiment established to identify and quantify N2O fluxes and controlling factors using automated field measurements. We measured trace gas fluxes, soil temperature, and moisture from fertilized and unfertilized balsa (Ochroma lagopus) plantations. Combining spatial and temporal sampling we evaluate if automatically measured time series of N2O emissions are representative of overall mean fluxes from fertilized loam under balsa. Soil trace gas fluxes were measured manually at 36 randomly distributed sampling locations per plot. Mean plot emissions were evaluated against fluxes measured by seven chambers commonly used for routine bimonthly manual measurements and against N2O emissions measured by two automated chambers at 4.6-hour sampling intervals. Trace gas fluxes were highly variable over 40 × 40 m plots. Nitrogen oxide fluxes were mainly spatially independent. Fertilization increased nitrogen oxide emissions but did not introduce spatial dependency of flux data. Within about 6 weeks fluxes approached pre-fertilization level again. Given high spatial variation of nitrogen oxide fluxes we find that automatically measured N2O fluxes represent the nature of the flux response well and are in the range of fluxes indicated by spatial sampling. When soils were relatively dry fertilization inhibited CH4 uptake.

Weitz, A. M.; Keller, M.; Linder, E.; Crill, P. M.

1999-12-01

261

Den use by arctic foxes in northern Alaska  

SciTech Connect

Den use by arctic foxes (Alopex lagopus) was examined near the Prudhoe Bay oil field and on a nearby undisturbed area on the Colville River Delta in northern Alaska. The density of dens at Prudhoe Bay (1 den/12 km/sup 2/) was approximately three times that on Colville Delta (1 den/34 km/sup 2/). Thirty-three percent of the Prudhoe Bay dens appeared to be of recent origin compared to 11% on the Colville Delta. Survival or production of juvenile foxes decreased on both study areas in 1977 when densities of lemmings (Dicrostonyx torquatus and Lemmus sibiricus) were low, but the decrease was less pronounced at Prudhoe Bay. Foxes that raised young at Prudhoe Bay in 1977 were those living near petroleum development facilities. The utilization of garbage by Prudhoe Bay foxes probably accounted for many of the observed differences between study sites. Common features of spring and summer den use by arctic foxes included a selection of historically preferred den sites, splitting litters into multiple dens, and the fidelity of some adult and juvenile foxes to dens in successive years. Winter use of dens was common at Prudhoe Bay. 24 references, 2 tables.

Eberhardt, L.E.; Garrott, R.A.; Hanson, W.C.

1983-01-01

262

PCB and organochlorine pesticides in northern fulmars (Fulmarus glacialis) from a High Arctic colony: chemical exposure, fate, and transfer to predators.  

PubMed

Organochlorine contaminant concentrations, associated fugacities, and stable isotopes of nitrogen (?(15) N) are reported for liver, whole body homogenate, and opportunistically collected samples of prey (amphipods), stomach oils, digestive tract contents, and guano for northern fulmars (Fulmarus glacialis) collected at Cape Vera, Devon Island in the Canadian High Arctic. Liver concentrations of polychlorinated biphenyls (?PCB) and ?DDT were on average 49.9 ± 35.4 ng g(-1) and 29.9 ± 25.2 ng g(-1) wet weight, respectively. Whole body homogenate concentrations of ?PCB and ?DDT were 637 ± 293 ng g(-1) and 365 ± 212 ng g(-1) wet weight, respectively. A mass and energy balance showed that whole body contaminant concentrations, which are seldom reported for Arctic seabirds, are critical in determining contaminant exposure and associated risk to predators such as the Arctic fox (Alopex lagopus). Biomagnification in the fulmars is evident, because concentrations and fugacities of contaminants were generally one to three orders of magnitude higher than those of likely prey items. The fate of diet-derived contaminants along the digestive tract is discussed, in particular with respect to stomach oils, which are used to feed chicks and for defensive purposes. The benefits of considering both concentrations and fugacities are demonstrated and provide information on the absorption and distribution of chemicals within the fulmars and contaminant transfer to offspring and predators. PMID:21647949

Foster, Karen L; Mallory, Mark L; Hill, Laura; Blais, Jules M

2011-09-01

263

A conceptual model for the impact of climate change on fox rabies in Alaska, 1980-2010.  

PubMed

The direct and interactive effects of climate change on host species and infectious disease dynamics are likely to initially manifest\\ at latitudinal extremes. As such, Alaska represents a region in the United States for introspection on climate change and disease. Rabies is enzootic among arctic foxes (Vulpes lagopus) throughout the northern polar region. In Alaska, arctic and red foxes (Vulpes vulpes) are reservoirs for rabies, with most domestic animal and wildlife cases reported from northern and western coastal Alaska. Based on passive surveillance, a pronounced seasonal trend in rabid foxes occurs in Alaska, with a peak in winter and spring. This study describes climatic factors that may be associated with reported cyclic rabies occurrence. Based upon probabilistic modelling, a stronger seasonal effect in reported fox rabies cases appears at higher latitudes in Alaska, and rabies in arctic foxes appear disproportionately affected by climatic factors in comparison with red foxes. As temperatures continue a warming trend, a decrease in reported rabid arctic foxes may be expected. The overall epidemiology of rabies in Alaska is likely to shift to increased viral transmission among red foxes as the primary reservoir in the region. Information on fox and lemming demographics, in addition to enhanced rabies surveillance among foxes at finer geographic scales, will be critical to develop more comprehensive models for rabies virus transmission in the region. PMID:23452510

Kim, B I; Blanton, J D; Gilbert, A; Castrodale, L; Hueffer, K; Slate, D; Rupprecht, C E

2014-02-01

264

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

265

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

266

Arctic fox home range characteristics in an oil-development area  

SciTech Connect

Spring and summer home ranges and local movements of arctic foxes (Alopex lagopus) were studied from 1975 to 1977 at the Prudhoe Bay oil-development area in northern Alaska. Twenty-seven adult and 62 juvenile foxes were captured, marked, and released. Nine adults and 5 juveniles were equipped with radio collars and monitored during 1976 and 1977. Home range size was 20.8 +/- 12.5 (SD) km/sup 2/ for 4 adult foxes and 3.7 +/- 1.7 km/sup 2/ for 5 juveniles. Home range configuration was similar for all marked members of individual families. Adult foxes were nocturnal and territorial. Foxes used oil-development sites for feeding, resting, and denning. Use of these became more comon late in the rearing season, as juveniles became more mobile. A major fluctuation in the availability of natural foods did not appear to alter ues of developed areas by foxes. The number of juvenile foxes observed at Prudhoe Bay decreased from 1976 to 1977, but the decrease was less pronounced than in a nearby undisturbed area.

Eberhardt, L.E. (Pacific Northwest Lab., Richland, WA); Hanson, W.C.; Bengtson, J.L.; Garrott, R.A.; Hanson, E.E.

1982-01-01

267

Mechanism of gene amplification via yeast autonomously replicating sequences.  

PubMed

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. PMID:25685838

Sehgal, Shelly; Kaul, Sanjana; Dhar, M K

2015-01-01

268

Reproductive responses to spatial and temporal prey availability in a coastal Arctic fox population.  

PubMed

1.?Input of external subsidies in the Arctic may have substantial effects on predator populations that otherwise would have been limited by low local primary productivity. 2.?We explore life-history traits, age-specific fecundity, litter sizes and survival, and the population dynamics of an Arctic fox (Vulpes lagopus) population to explore the influence of the spatial distribution and temporal availability of its main prey; including both resident and migrating (external) prey resources. 3.?This study reveals that highly predictable cross-boundary subsidies from the marine food web, acting through seasonal access to seabirds, sustain larger local Arctic fox populations. Arctic fox dens located close to the coast in Svalbard were found to have higher occupancy rates, as expected from both high availability and high temporal and spatial predictability of prey resources (temporally stable external subsidies). Whereas the occupancy rate of inland dens varied between years in relation to the abundance of reindeer carcasses (temporally varying resident prey). 4.?With regard to demography, juvenile Arctic foxes in Svalbard have lower survival rates and a high age of first reproduction compared with other populations. We suggest this may be caused by a lack of unoccupied dens and a saturated population. PMID:22211323

Eide, Nina E; Stien, Audun; Prestrud, Pål; Yoccoz, Nigel G; Fuglei, Eva

2012-05-01

269

Hammondia triffittae n. comb. of foxes ( Vulpes spp.): biological and molecular characteristics and differentiation from Hammondia heydorni of dogs.  

PubMed

Genomic DNAs from 3 oocyst isolates of Hammondia sp. from foxes (Vulpes vulpes and V. lagopus) and 1 oocyst isolate of Hammondia heydorni from a dog, were examined by PCR and sequence analysis of 6 loci in order to determine whether the isolates were conspecific. Consistent genetic differences were found between the fox and dog isolates, respectively, at the ITS-2 region, the lsu rRNA gene, the alpha tubulin gene and the HSP70 gene, but not at the ssu rRNA gene or ITS-1 locus. Infection experiments established that dogs were unsuitable as definitive hosts for Hammondia sp. of foxes; hence this species is regarded as separate from H. heydorni of wolf-like canids, but probably identical with Isospora triffittae (syn. Isospora triffitti) previously reported from foxes. This species has therefore been named Hammondia triffittae n. comb. Reindeer, moose, sheep, goats, foxes and rabbits may act as intermediate hosts for H. triffittae. Muscle tissues of inoculated intermediate hosts were infectious for foxes from 16 days post-infection. Oocysts of H. triffittae were subspherical, averaging 12.5 × 10.9 ?m in size. The lsu rRNA gene and the alpha tubulin gene seem to be suitable genetic markers for differentiating between H. triffittae and H. heydorni. PMID:20854709

Gjerde, Bjørn; Dahlgren, Stina S

2011-03-01

270

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

271

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

NASA Astrophysics Data System (ADS)

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 determine whether White-tailed Ptarmigan on Mt. Evans, Colorado have experienced recent environmental changes resulting in shifts in genetic diversity, gene frequency, and nutritional ecology. We genotyped 115 individuals spanning the three time periods using nine polymorphic microsatellite loci in our genetic analysis. These samples were also analyzed for stable carbon and nitrogen isotopic composition. We found a slight trend of lower heterozygosity through time and allelic richness values were lower in more recent times. We found no changes in allele frequencies across time periods suggesting that population sizes have not changed dramatically. Feather ?13C and ?15N values decreased significantly across time periods, whereas the range in isotope values increased consistently from the late 1930s to the later time periods. Inferred changes in the nutritional ecology of White-tailed Ptarmigan on Mt. Evans relates primarily to increased atmospheric deposition of nutrients that likely influenced foraging habits and tundra plant composition and nutritional quality. We briefly discuss similar ongoing work on the neighboring population in Rocky Mountain National Park, Colorado and tie in genetic results from across the species range.

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

2010-12-01

272

Effects of climate change on nutrition and genetics of White-tailed Ptarmigan  

USGS Publications Warehouse

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 determine whether White-tailed Ptarmigan on Mt. Evans, Colorado, have experiences recent environmental changes resulting in shifts in genetic diversity, gene frequency, and nutritional ecology. We genotyped 115 individuals spanning the three time periods, using nine polymorphic microsatellite loci in our genetic analysis. These samples were also analyzed for stable carbon and nitrogen isotopic composition. We found a slight trend of lower heterozygosity through time, and allelic richness values were significantly lower in more recent times, but not significantly using an alpha of 0.05 (P 13C and ?15N values decreased significantly across time periods, whereas the range in isotope values increased consistently from the late 1930s to the late time periods. Inferred changes in the nutritional ecology of White-tailed Ptarmigan on Mt. Evans relate primarily to increased atmospheric deposition of nutrients that likely influenced foraging habits and tundra plant composition and nutritional quality. Future work seeks to integrate genetic and isotopic data with long-term demographics to develop a detailed understanding of the interaction among environmental stressors on the long-term viability of ptarmigan populations.

Oyler-McCance, Sara J.; Stricker, Craig A.; St. John, Judy, Braun, Clait E.; Wann, Gregory T.; O'Donnell, Michael S.; Aldridge, Cameron L.

2011-01-01

273

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

274

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

275

A conceptual model for the impact of climate change on fox rabies in Alaska, 1980–2010  

PubMed Central

The direct and interactive effects of climate change on host species and infectious disease dynamics are likely to initially manifest at latitudinal extremes. As such, Alaska represents a region in the United States for introspection on climate change and disease. Rabies is enzootic among arctic foxes (Vulpes lagopus) throughout the northern polar region. In Alaska, arctic and red foxes (Vulpes vulpes) are reservoirs for rabies, with most domestic animal and wildlife cases reported from northern and western coastal Alaska. Based on passive surveillance, a pronounced seasonal trend in rabid foxes occurs in Alaska, with a peak in winter and spring. This study describes climatic factors that may be associated with reported cyclic rabies occurrence. Based upon probabilistic modeling, a stronger seasonal effect in reported fox rabies cases appears at higher latitudes in Alaska, and rabies in arctic foxes appear disproportionately affected by climatic factors in comparison to red foxes. As temperatures continue a warming trend a decrease in reported rabid arctic foxes may be expected. The overall epidemiology of rabies in Alaska is likely to shift to increased viral transmission among red foxes as the primary reservoir in the region. Information on fox and lemming demographics, in addition to enhanced rabies surveillance among foxes at finer geographic scales, will be critical to develop more comprehensive models for rabies virus transmission in the region. PMID:23452510

Kim, Bryan I.; Blanton, Jesse D.; Gilbert, Amy; Castrodale, Louisa; Hueffer, Karsten; Slate, Dennis; Rupprecht, Charles E.

2013-01-01

276

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

277

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

278

Functional responses of the rough-legged buzzard in a multi-prey system.  

PubMed

The functional response is a key element of predator-prey interactions. Basic functional response theory explains foraging behavior of individual predators, but many empirical studies of free-ranging predators have estimated functional responses by using population-averaged data. We used a novel approach to investigate functional responses of an avian predator (the rough legged-buzzard Buteo lagopus Pontoppidan, 1763) to intra-annual spatial variation in rodent density in subarctic Sweden, using breeding pairs as the sampling unit. The rough-legged buzzards responded functionally to Norwegian lemmings (Lemmus lemmus L. 1758), grey-sided voles (Myodes rufocanus Sundevall, 1846) and field voles (Microtus agrestis L. 1761), but different rodent prey were not utilised according to relative abundance. The functional response to Norwegian lemmings was a steep type II curve and a more shallow type III response to grey-sided voles. The different shapes of these two functional responses were likely due to combined effects of differences between lemmings and grey-sided voles in habitat utilisation, anti-predator behaviour and size-dependent vulnerability to predation. Diet composition changed less than changes in relative prey abundance, indicating negative switching, with high disproportional use of especially lemmings at low relative densities. Our results suggest that lemmings and voles should be treated separately in future empirical and theoretical studies in order to better understand the role of predation in this study system. PMID:24448699

Hellström, P; Nyström, J; Angerbjörn, A

2014-04-01

279

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

280

Regional distribution shifts help explain local changes in wintering raptor abundance: implications for interpreting population trends.  

PubMed

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

281

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

282

Importance of the national petroleum reserve-alaska for aquatic birds.  

PubMed

We used data from aerial surveys (1992-2010) of >100,000 km(2) and ground surveys (1998-2004) of >150 km(2) to estimate the density and abundance of birds on the North Slope of Alaska (U.S.A.). In the ground surveys, we used double sampling to estimate detection ratios. We used the aerial survey data to compare densities of birds and Arctic fox (Vulpes lagopus), the major nest predator of birds, on the North Slope, in Prudhoe Bay, and in nearby areas. We partitioned the Prudhoe Bay oil field into 2 × 2 km plots and determined the relation between density of aquatic birds and density of roads, buildings, and other infrastructure in these plots. Abundance and density (birds per square kilometer) of 3 groups of aquatic birds-waterfowl, loons, and grebes; shorebirds; and gulls, terns, and jaegers-were highest in the National Petroleum Reserve-Alaska (NPRA) and lowest in the Arctic National Wildlife Refuge. Six other major wetlands occur in the Arctic regions of Canada and Russia, but the largest population of aquatic birds was in the NPRA. Aquatic birds were concentrated in the northern part of the NPRA. For example, an area that covered 18% of the NPRA included 53% of its aquatic birds. The aerial surveys showed that bird density was not lower and fox density was not higher in Prudhoe Bay than in surrounding areas. Density of infrastructure did not significantly affect bird density for any group of species. Our results establish that the NPRA is one of the most important areas for aquatic birds in the Arctic. Our results and those of others also indicate that oil production, as practiced in Prudhoe Bay, does not necessarily lead to substantial declines in bird density or productivity in or near the developed areas. Prioridades para la Conservación de Aves en el Norte de Alaska. PMID:23937114

Bart, Jonathan; Platte, Robert M; Andres, Brad; Brown, Stephen; Johnson, James A; Larned, William

2013-12-01

283

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

284

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

285

Bald eagles and sea otters in the Aleutian Archipelago: indirect effects of trophic cascades.  

USGS Publications Warehouse

Because sea otters (Enhydra lutris) exert a wide array of direct and indirect effects on coastal marine ecosystems throughout their geographic range, we investigated the potential influence of sea otters on the ecology of Bald Eagles (Haliaeetus leucocephalus) in the Aleutian Islands, Alaska, USA. We studied the diets, productivity, and density of breeding Bald Eagles on four islands during 1993-1994 and 2000-2002, when sea otters were abundant and scarce, respectively. Bald Eagles depend on nearshore marine communities for most of their prey in this ecosystem, so we predicted that the recent decline in otter populations would have an indirect negative effect on diets and demography of Bald Eagles. Contrary to our predictions, we found no effects on density of breeding pairs on four islands from 1993-1994 to 2000-2002. In contrast, diets and diet diversity of Bald Eagles changed considerably between the two time periods, likely reflecting a change in prey availability resulting from the increase and subsequent decline in sea otter populations. The frequency of sea otter pups, rock greenling (Hexagammus lagocephalus), and smooth lumpsuckers (Aptocyclus ventricosus) in the eagle's diet declined with corresponding increases in Rock Ptarmigan (Lagopus mutus), Glaucous-winged Gulls (Larus glaucescens), Atka mackerel (Pleurogrammus monopterygius), and various species of seabirds during the period of the recent otter population decline. Breeding success and productivity of Bald Eagles also increased during this time period, which may be due to the higher nutritional quality of avian prey consumed in later years. Our results provide further evidence of the wide-ranging indirect effects of sea otter predation on nearshore marine communities and another apex predator, the Bald Eagle. Although the indirect effects of sea otters are widely known, this example is unique because the food-web pathway transcended five species and several trophic levels in linking one apex predator to another.

Anthony, R.G.; Estes, J.A.; Ricca, M.A.; Miles, A.K.; Forsman, E.D.

2008-01-01

286

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

PubMed

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. PMID:21802422

Dubey, J P; Velmurugan, G V; Rajendran, 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

2011-09-01

287

Characterization of a new epidemic necrotic pyoderma in fur animals and its association with Arcanobacterium phocae infection.  

PubMed

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

288

Signatures of large-scale and local climates on the demography of white-tailed ptarmigan in Rocky Mountain National Park, Colorado, USA  

NASA Astrophysics Data System (ADS)

Global climate change may impact wildlife populations by affecting local weather patterns, which, in turn, can impact a variety of ecological processes. However, it is not clear that local variations in ecological processes can be explained by large-scale patterns of climate. The North Atlantic oscillation (NAO) is a large-scale climate phenomenon that has been shown to influence the population dynamics of some animals. Although effects of the NAO on vertebrate population dynamics have been studied, it remains uncertain whether it broadly predicts the impact of weather on species. We examined the ability of local weather data and the NAO to explain the annual variation in population dynamics of white-tailed ptarmigan (Lagopus leucurus) in Rocky Mountain National Park, USA. We performed canonical correlation analysis on the demographic subspace of ptarmigan and local-climate subspace defined by the empirical orthogonal function (EOF) using data from 1975 to 1999. We found that two subspaces were significantly correlated on the first canonical variable. The Pearson correlation coefficient of the first EOF values of the demographic and local-climate subspaces was significant. The population density and the first EOF of local-climate subspace influenced the ptarmigan population with 1-year lags in the Gompertz model. However, the NAO index was neither related to the first two EOF of local-climate subspace nor to the first EOF of the demographic subspace of ptarmigan. Moreover, the NAO index was not a significant term in the Gompertz model for the ptarmigan population. Therefore, local climate had stronger signature on the demography of ptarmigan than did a large-scale index, i.e., the NAO index. We conclude that local responses of wildlife populations to changing climate may not be adequately explained by models that project large-scale climatic patterns.

Wang, Guiming; Hobbs, Thompson; Galbraith, Hector; Giesen, Kenneth

2002-06-01

289

Morphological and molecular characterization and phylogenetic placement of Sarcocystis capreolicanis and Sarcocystis silva n. sp. from roe deer (Capreolus capreolus) in Norway.  

PubMed

Sarcocysts were isolated from the muscle tissue of three roe deer from southeastern Norway and examined by light microscopy, scanning electron microscopy and/or sequencing of the small subunit ribosomal RNA (ssu rRNA) gene. By light microscopy, four sarcocyst types were found, including those of Sarcocystis gracilis and Sarcocystis oviformis, which had been characterized previously. The third cyst type had about 10 ?m long, flexible, hair-like surface protrusions, consistent with those of Sarcocystis capreolicanis, and differed genetically from other known species. The name S. capreolicanis was therefore assigned to this sequence type. The fourth cyst type had densely packed, upright, finger-like surface protrusions, about 8 ?m long, and was morphologically similar to an unnamed Sarcocystis sp. reported from roe deer in other countries, and identical at the ssu rRNA gene to Sarcocystis sp. Type D previously reported from moose. This species was assigned the new name Sarcocystis silva. Both S. capreolicanis and S. silva displayed considerable intraspecific variation at the ssu rRNA gene. In phylogenetic analyses based on ssu rRNA gene sequences, S. capreolicanis grouped together with other canine-transmitted Sarcocystis species, whereas S. silva was most closely related to Sarcocystis rangiferi and Sarcocystis tarandi of reindeer. Roe deer muscles containing numerous cysts of S. gracilis were fed to a silver fox (Vulpes vulpes) and a blue fox (Vulpes lagopus), both of which started shedding Sarcocystis sporocysts in their faeces 9 days later, and harboured numerous oocysts, measuring about 20?×?15 ?m, in their intestinal mucosa upon euthanasia 14 days post-inoculation. DNA derived from these oocysts was amplified and sequenced at the ssu rRNA gene and belonged to S. gracilis, confirming for the first time by molecular methods that foxes are definitive hosts for this species. PMID:21853224

Gjerde, Bjørn

2012-03-01

290

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

291

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

292

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

293

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

294

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

295

Biogeochemistry and nitrogen cycling in an Arctic, volcanic ecosystem  

NASA Astrophysics Data System (ADS)

As part of a study on Mars Analogue environments, the biogeochemistry of Sverrefjellet Volcano, Bocfjorden, Svalbard, was conducted and compared to surrounding glacial, thermal spring, and sedimentary environments. An understanding of how nitrogen might be distributed in a landscape that had extinct or very cold adapted, slow- growing extant organisms should be useful for detecting unknown life forms. From high elevations (900 m) to the base of the volcano (sea level), soil and rock ammonium concentrations were uniformly low, typically less than 1- 3 micrograms per gm of rock or soil. In weathered volcanic soils, reduced nitrogen concentrations were higher, and oxidized nitrogen concentrations lower. The opposite was found in a weathered Devonian sedimentary soil. Plants and lichens growing on volcanic soils have an unusually wide range in N isotopic compositions from -5 to +12‰, a range rarely measured in temperate ecosystems. Nitrogen contents and isotopic compositions of volcanic soils and rocks were strongly influenced by the presence or absence of terrestrial herbivores or marine avifauna with higher concentrations of N and elevated N isotopic compositions occurring as patches in areas immediately influenced by reindeer, Arctic fox ( Alopex lagopus), and marine birds. Because of the extreme conditions in this area, ephemeral deposition of herbivore feces results in a direct and immediate N pulses into the ecosystem. The lateral extent and distribution of marine- derived nitrogen was measured on a landscape scale surrounding an active fox den. Nitrogen was tracked from the bones of marine birds to soil to vegetation. Because of extreme cold, slow biological rates and nitrogen cycling, a mosaic of N patterns develops on the landscape scale.

Fogel, M. L.; Benning, L.; Conrad, P. G.; Eigenbrode, J.; Starke, V.

2007-12-01

296

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

297

High exposure rates of anticoagulant rodenticides in predatory bird species in intensively managed landscapes in Denmark.  

PubMed

The extensive use of anticoagulant rodenticides (ARs) for rodent control has led to widespread secondary exposure in nontarget predatory wildlife species. We investigated exposure rates and concentrations of five ARs in liver samples from five raptors and six owls from Denmark. A total of 430 birds were analysed. ARs were detected in 84-100 % of individual birds within each species. Multiple AR exposure was detected in 73 % of all birds. Average number of substances detected in individual birds was 2.2 with no differences between owls and raptors. Difenacoum, bromadiolone, and brodifacoum were the most prevalent substances and occurred in the highest concentrations. Second-generation ARs made up 96 % of the summed AR burden. Among the six core species (sample size >30), summed AR concentrations were lower in rough-legged buzzard (Buteo lagopus) and long-eared owl (Asio otus) than in barn owl (Tyto alba), buzzard (B. buteo), kestrel (Falco tinnunculus), and tawny owl (Strix aluco). There was a strong tendency for seasonal variations in the summed AR concentration with levels being lowest during autumn, which is probably related to an influx of less-exposed migrating birds from northern Scandinavia during autumn. High hepatic AR residue concentrations (>100 ng/g wet weight), which have been associated with symptoms of rodenticide poisoning and increased mortality, were recorded high frequencies (12.9-37.4 %) in five of the six core species. The results suggest that the present use of ARs in Denmark, at least locally, may have adverse effects on reproduction and, ultimately, population status in some raptors and owls. PMID:22588365

Christensen, Thomas Kjær; Lassen, Pia; Elmeros, Morten

2012-10-01

298

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

299

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

300

Factors influencing nesting success of king eiders on northern Alaska's Coastal Plain  

USGS Publications Warehouse

King eider (Somateria spectabilis) populations have declined markedly in recent decades for unknown reasons. Nest survival is one component of recruitment, and a female's chance of reproductive success increases with her ability to choose an appropriate nesting strategy. We estimated variation in daily nest survival of king eiders at 2 sites, Teshekpuk and Kuparuk, Alaska, USA, 2002-2005. We evaluated both a priori and exploratory competing models of nest survival that considered importance of nest concealment, seclusion, and incubation constancy as strategies to avoid 2 primary egg predators, avian (Larus spp., Stercorarius spp., and Corvus corax) and fox (Alopex lagopus). We used generalized nonlinear techniques to examine factors affecting nest survival rates and information-theoretic approaches to select among competing models. Estimated nest survival, accounting for a nest visitation effect, varied considerably across sites and years (0.21-0.57); however, given our small sample size, much of this variation maybe attributable to sampling variation (??process = 0.007, 95% CI: 0.003-0.070). Nest survival was higher at Kuparuk than Teshekpuk in all years; however, due to the correlative nature of our data, we cannot determine the underlying causes with any certainty. We found mixed support for the concealed breeding strategy, females derived no benefit from nesting in areas with more willow (Salix spp.; measure of concealment) except that the observer effect diminished as willow cover increased. We suggest these patterns are due to conflicting predation pressures. Nest survival was not higher on islands (measure of seclusion) or with increased incubation constancy but was higher post-fox removal, indicating that predator control on breeding grounds could be a viable management option. Nest survival was negatively affected by our nest visitations, most likely by exposing the nest to avian scavengers. We recommend precautions be taken to limit the effects of nest visits in future studies and to consider them as a possible negative bias in estimated nest survival. Future models of the impacts of development within the breeding grounds of king eider should consider the influence of humans in the vicinity of nests.

Bentzen, R.L.; Powell, A.N.; Suydam, R.S.

2008-01-01

301

Benefiting from a migratory prey: spatio-temporal patterns in allochthonous subsidization of an Arctic predator.  

PubMed

1.?Flows of nutrients and energy across ecosystem boundaries have the potential to subsidize consumer populations and modify the dynamics of food webs, but how spatio-temporal variations in autochthonous and allochthonous resources affect consumers' subsidization remains largely unexplored. 2.?We studied spatio-temporal patterns in the allochthonous subsidization of a predator living in a relatively simple ecosystem. We worked on Bylot Island (Nunavut, Canada), where arctic foxes (Vulpes lagopus L.) feed preferentially on lemmings (Lemmus trimucronatus and Dicrostonyx groenlandicus Traill), and alternatively on colonial greater snow geese (Anser caerulescens atlanticus L.). Geese migrate annually from their wintering grounds (where they feed on farmlands and marshes) to the Canadian Arctic, thus generating a strong flow of nutrients and energy across ecosystem boundaries. 3.?We examined the influence of spatial variations in availability of geese on the diet of fox cubs (2003-2005) and on fox reproductive output (1996-2005) during different phases of the lemming cycle. 4.?Using stable isotope analysis and a simple statistical routine developed to analyse the outputs of a multisource mixing model (SIAR), we showed that the contribution of geese to the diet of arctic fox cubs decreased with distance from the goose colony. 5.?The probability that a den was used for reproduction by foxes decreased with distance from the subsidized goose colony and increased with lemming abundance. When lemmings were highly abundant, the effect of distance from the colony disappeared. The goose colony thus generated a spatial patterning of reproduction probability of foxes, while the lemming cycle generated a strong temporal variation of reproduction probability of foxes. 6.?This study shows how the input of energy owing to the large-scale migration of prey affects the functional and reproductive responses of an opportunistic consumer, and how this input is spatially and temporally modulated through the foraging behaviour of the consumer. Thus, perspectives of both landscape and foraging ecology are needed to fully resolve the effects of subsidies on animal demographic processes and population dynamics. PMID:22268371

Giroux, Marie-Andrée; Berteaux, Dominique; Lecomte, Nicolas; Gauthier, Gilles; Szor, Guillaume; Bêty, Joël

2012-05-01

302

Some autecological characteristics of early to late successional tree species in Venezuela  

NASA Astrophysics Data System (ADS)

The breadth of the continuum concept of strategy with respect to succession was tested on 21 tree and shrub species common in either unlogged or logged stands, respectively, in the Forest Reserve of Caparo, Venezuela, by examining morphological, physiological and population characteristics. Based on a preliminary abundance analysis, `early', `mid' and `late' successional species as well as `generalists' were distinguished. Early successional species, i.e. Ochroma lagopus, Heliocarpus popayanensis and Cecropia peltata were similar in many autecological aspects, e.g. monolayered leaf arrangement, orthotropic architectural models, no adaptive reiteration, clumped distribution, but differed in gap association and distribution along a drainage gradient. Mid-successional species established themselves both in large and small gaps (> 300 m[sup2 ]; 80-300 m[sup2 ]) and showed a clumped to regular distribution pattern in logged areas; they exhibited more diverse crown and leaf characteristics than early successional species. Late successional species established themselves only in small gaps and understorey, and showed a regular spatial pattern in undisturbed areas. All late successional species displayed architectural models with plagiotropic lateral axes and showed a multilayered leaf arrangement. Adaptive reiteration was a common feature of late successional species which could be further subdivided into large, medium-sized and small trees, indicating different light requirements at maturity. Generalists were common treelet and shrub species in both disturbed and undisturbed sites where they are also capable of completing their life cycle. The light compensation point (LCP) of an individual plant was strongly influenced by its crown illuminance. Large late successional species showed the widest range of LCP values, reflecting the increasing light availability with increasing height in mature forest. On the basis of many autecological characteristics, it was found (i) that there is in fact a continuum of species strategies with respect to succession even among early and mid-successional species and (ii) that the latter group of species showed the widest breadth of autecological traits, reflecting the heterogeneous environment in which they establish and mature.

Kammesheidt, Ludwig

2000-01-01

303

Intrapopulation Variability Shaping Isotope Discrimination and Turnover: Experimental Evidence in Arctic Foxes  

PubMed Central

Background Tissue-specific stable isotope signatures can provide insights into the trophic ecology of consumers and their roles in food webs. Two parameters are central for making valid inferences based on stable isotopes, isotopic discrimination (difference in isotopic ratio between consumer and its diet) and turnover time (renewal process of molecules in a given tissue usually measured when half of the tissue composition has changed). We investigated simultaneously the effects of age, sex, and diet types on the variation of discrimination and half-life in nitrogen and carbon stable isotopes (?15N and ?13C, respectively) in five tissues (blood cells, plasma, muscle, liver, nail, and hair) of a top predator, the arctic fox Vulpes lagopus. Methodology/Principal Findings We fed 40 farmed foxes (equal numbers of adults and yearlings of both sexes) with diet capturing the range of resources used by their wild counterparts. We found that, for a single species, six tissues, and three diet types, the range of discrimination values can be almost as large as what is known at the scale of the whole mammalian or avian class. Discrimination varied depending on sex, age, tissue, and diet types, ranging from 0.3‰ to 5.3‰ (mean ?=?2.6‰) for ?15N and from 0.2‰ to 2.9‰ (mean ?=?0.9‰) for ?13C. We also found an impact of population structure on ?15N half-life in blood cells. Varying across individuals, ?15N half-life in plasma (6 to 10 days) was also shorter than for ?13C (14 to 22 days), though ?15N and ?13C half-lives are usually considered as equal. Conclusion/Significance Overall, our multi-factorial experiment revealed that at least six levels of isotopic variations could co-occur in the same population. Our experimental analysis provides a framework for quantifying multiple sources of variation in isotopic discrimination and half-life that needs to be taken into account when designing and analysing ecological field studies. PMID:21731715

Lecomte, Nicolas; Ahlstrøm, Øystein; Ehrich, Dorothée; Fuglei, Eva; Ims, Rolf A.; Yoccoz, Nigel G.

2011-01-01

304

Population dynamics and resource use of red deer after release from harvesting in New Zealand  

Microsoft Academic Search

Despite periods of extensive government-funded control, fluctuating commercial exploitation and ongoing recreational hunting, little is known about how red deer (Cervus elaphus scoticus Lönnberg) in New Zealand respond to the cessation of harvesting in terms of population growth rate and resource use. We describe the population dynamics and resource use of red deer in a montane catchment over 5 years

David M. Forsyth; Robert B. Allen; Anna E. Marburg; Darryl I. MacKenzie; Malcolm J. W. Douglas; Arthur Rylah

305

Exposure and effects assessment of persistent organohalogen contaminants in arctic wildlife and fish.  

PubMed

Persistent organic pollutants (POPs) encompass an array of anthropogenic organic and elemental substances and their degradation and metabolic byproducts that have been found in the tissues of exposed animals, especially POPs categorized as organohalogen contaminants (OHCs). OHCs have been of concern in the circumpolar arctic for decades. For example, as a consequence of bioaccumulation and in some cases biomagnification of legacy (e.g., chlorinated PCBs, DDTs and CHLs) and emerging (e.g., brominated flame retardants (BFRs) and in particular polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs) including perfluorooctane sulfonate (PFOS) and perfluorooctanic acid (PFOA) found in Arctic biota and humans. Of high concern are the potential biological effects of these contaminants in exposed Arctic wildlife and fish. As concluded in the last review in 2004 for the Arctic Monitoring and Assessment Program (AMAP) on the effects of POPs in Arctic wildlife, prior to 1997, biological effects data were minimal and insufficient at any level of biological organization. The present review summarizes recent studies on biological effects in relation to OHC exposure, and attempts to assess known tissue/body compartment concentration data in the context of possible threshold levels of effects to evaluate the risks. This review concentrates mainly on post-2002, new OHC effects data in Arctic wildlife and fish, and is largely based on recently available effects data for populations of several top trophic level species, including seabirds (e.g., glaucous gull (Larus hyperboreus)), polar bears (Ursus maritimus), polar (Arctic) fox (Vulpes lagopus), and Arctic charr (Salvelinus alpinus), as well as semi-captive studies on sled dogs (Canis familiaris). Regardless, there remains a dearth of data on true contaminant exposure, cause-effect relationships with respect to these contaminant exposures in Arctic wildlife and fish. Indications of exposure effects are largely based on correlations between biomarker endpoints (e.g., biochemical processes related to the immune and endocrine system, pathological changes in tissues and reproduction and development) and tissue residue levels of OHCs (e.g., PCBs, DDTs, CHLs, PBDEs and in a few cases perfluorinated carboxylic acids (PFCAs) and perfluorinated sulfonates (PFSAs)). Some exceptions include semi-field studies on comparative contaminant effects of control and exposed cohorts of captive Greenland sled dogs, and performance studies mimicking environmentally relevant PCB concentrations in Arctic charr. Recent tissue concentrations in several arctic marine mammal species and populations exceed a general threshold level of concern of 1 part-per-million (ppm), but a clear evidence of a POP/OHC-related stress in these populations remains to be confirmed. There remains minimal evidence that OHCs are having widespread effects on the health of Arctic organisms, with the possible exception of East Greenland and Svalbard polar bears and Svalbard glaucous gulls. However, the true (if any real) effects of POPs in Arctic wildlife have to be put into the context of other environmental, ecological and physiological stressors (both anthropogenic and natural) that render an overall complex picture. For instance, seasonal changes in food intake and corresponding cycles of fattening and emaciation seen in Arctic animals can modify contaminant tissue distribution and toxicokinetics (contaminant deposition, metabolism and depuration). Also, other factors, including impact of climate change (seasonal ice and temperature changes, and connection to food web changes, nutrition, etc. in exposed biota), disease, species invasion and the connection to disease resistance will impact toxicant exposure. Overall, further research and better understanding of POP/OHC impact on animal performance in Arctic biota are recommended. Regardless, it could be argued that Arctic wildlife and fish at the highest potential risk of POP/OHC exposure and mediated effects are East Greenland, Svalbard and (West and South) Hudson Bay

Letcher, Robert J; Bustnes, Jan Ove; Dietz, Rune; Jenssen, Bjørn M; Jørgensen, Even H; Sonne, Christian; Verreault, Jonathan; Vijayan, Mathilakath M; Gabrielsen, Geir W

2010-07-01

306

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

307

Health effects from long-range transported contaminants in Arctic top predators: An integrated review based on studies of polar bears and relevant model species.  

PubMed

The aim of this review is to provide a thorough overview of the health effects from the complexed biomagnified mixture of long-range transported industrial organochlorines (OCs), polybrominated diphenyl ethers (PBDEs), perfluorinated compounds (PFCs) and mercury (Hg) on polar bear (Ursus maritimus) health. Multiple scientific studies of polar bears indicate negative relationships between exposure to these contaminants and health parameters; however, these are all of a correlative nature and do not represent true cause-and-effects. Therefore, information from controlled studies of farmed Norwegian Arctic foxes (Vulpes lagopus) and housed East and West Greenland sledge dogs (Canis familiaris) were included as supportive weight of evidence in the clarification of contaminant exposure and health effects in polar bears. The review showed that hormone and vitamin concentrations, liver, kidney and thyroid gland morphology as well as reproductive and immune systems of polar bears are likely to be influenced by contaminant exposure. Furthermore, exclusively based on polar bear contaminant studies, bone density reduction and neurochemical disruption and DNA hypomethylation of the brain stem seemed to occur. The range of tissue concentration, at which these alterations were observed in polar bears, were ca. 1-70,000 ng/g lw for OCs (blood plasma concentrations of some PCB metabolites even higher), ca. 1-1000 ng/g lw for PBDEs and for PFCs and Hg 114-3052 ng/g ww and 0.1-50 microg/g ww, respectively. Similar concentrations were found in farmed foxes and housed sledge dogs while the lack of dose response designs did not allow an estimation of threshold levels for oral exposure and accumulated tissue concentrations. Nor was it possible to pinpoint a specific group of contaminants being more important than others nor analyze their interactions. For East Greenland polar bears the corresponding daily SigmaOC and SigmaPBDE oral exposure was estimated to be 35 and 0.34 microg/kg body weight, respectively. Furthermore, PFC concentrations, at which population effect levels could occur, are likely to be reached around year 2012 for the East Greenland polar bear subpopulation if current increasing temporal trends continue. Such proposed reproductive population effects were supported by physiological based pharmacokinetic (PBPK) modelling of critical body residues (CBR) with risk quotients >or=1 for SigmaPCB, dieldrin, SigmaPFC and SigmaOHC (organohalogen contaminant). The estimated daily TEQ for East Greenland polar bears and East Greenland sledge dogs were 32-281-folds above WHO SigmaTEQ guidelines for humans. Compared to human tolerable daily intake (TDI), these were exceeded for PCBs, dieldrin, chlordanes and SigmaHCH in East Greenland polar bears. Comparisons like these should be done with caution, but together with the CBR modelling and T-score estimations, these were the only available tools for polar bear risk evaluation. In conclusion, polar bears seem to be susceptible to contaminant induced stress that may have an overall sub-clinical impact on their health and population status via impacts on their immune and reproductive systems. PMID:20398940

Sonne, Christian

2010-07-01

308

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

309

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

310

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

311

First Report of 13 Species of Culicoides (Diptera: Ceratopogonidae) in Mainland Portugal and Azores by Morphological and Molecular Characterization  

PubMed Central

The genus Culicoides (Diptera: Ceratopogonidae) contains important vectors of animal and human diseases, including bluetongue, African horse sickness and filariosis. A major outbreak of bluetongue occurred in mainland Portugal in 2004, forty eight years after the last recorded case. A national Entomological Surveillance Plan was initiated in mainland Portugal, Azores and the Madeira archipelagos in 2005 in order to better understand the disease and facilitate policy decisions. During the survey, the most prevalent Culicoides species in mainland Portugal was C. imicola (75.3%) and species belonging to the Obsoletus group (6.5%). The latter were the most prevalent in Azores archipelago, accounting for 96.7% of the total species identified. The Obsoletus group was further characterized by multiplex Polymerase Chain Reaction to species level showing that only two species of this group were present: C. obsoletus sensu strictu (69.6%) and C. scoticus (30.4%). Nine species of Culicoides were detected for the first time in mainland Portugal: C. alazanicus, C. bahrainensis, C. deltus, C. lupicaris, C. picturatus, C. santonicus, C. semimaculatus, C. simulator and C. subfagineus. In the Azores, C. newsteadi and C. circumscriptus were identified for the first time from some islands, and bluetongue vectors belonging to the Obsoletus group (C. obsoletus and C. scoticus) were found to be widespread. PMID:22536340

Pereira da Fonseca, Isabel; Delécolle, Jean-Claude; Wilson, Anthony; Meireles, José; Lucientes, Javier; Ribeiro, Rita; Boinas, Fernando

2012-01-01

312

The Mondrian matrix: Culicoides biting midge abundance and seasonal incidence during the 2006-2008 epidemic of bluetongue in the Netherlands.  

PubMed

During the northern Europe epidemic of bluetongue (BT), Onderstepoort-type blacklight traps were used to capture Culicoides Latreille (Diptera: Ceratopogonidae) biting midges weekly between November 2006 and December 2008 on 21 livestock farms in the Netherlands. Proven and potential vectors for the bluetongue virus (BTV) comprised almost 80% of the midges collected: the Obsoletus complex, constituting C. obsoletus (Meigen) and C. scoticus Downes & Kettle (44.2%), C. dewulfi Goetghebuer (16.4%), C. chiopterus (Meigen) (16.3%) and C. pulicaris (Linnaeus) (0.1%). Half of the 24 commonest species of Culicoides captured completed only one (univoltine) or two (bivoltine) generations annually, whereas multivoltine species (including all BTV vectors) cycled through five to six generations (exceeding the one to four generations calculated in earlier decades). Whether this increment signals a change in the phenology of northern Europe Culicoides or simply is an adaptive response that manifests during warmer episodes, thus heightening periodically the incursive potential of midge-borne arboviruses, remains to be clarified. Culicoides duddingstoni Kettle & Lawson, C. grisescens Edwards, C. maritimus Kieffer, C. pallidicornis Kieffer and C. riethi Kieffer are new records for the biting midge fauna of the Netherlands. It is suggested that C. punctatus (Meigen) be added to the European list of vector Culicoides. PMID:23834350

Meiswinkel, R; Scolamacchia, F; Dik, M; Mudde, J; Dijkstra, E; Van Der Ven, I J K; Elbers, A R W

2014-03-01

313

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

314

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

315

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

316

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

317

An unrecognized species of the Culicoides obsoletus complex feeding on livestock in The Netherlands.  

PubMed

In studies on Culicoides attacking livestock in the Netherlands, we chanced upon a species of the Obsoletus complex that we do not recognize, but whose dark wing pattern is distinctive. Nine cytochrome c oxidase (CO1) sequences of our so-called 'dark obsoletus' support its status as a separate species, the sequences differing significantly from those representing Culicoides obsoletus (Meigen) (90-91% homology) and Culicoides scoticus Downes & Kettle (87-88% homology). In the last decade, several research groups in Europe have encountered 'mystery species' related to C. obsoletus and in some instances have made their sequences for various genetic loci available in GenBank. These include a CO1 series submitted from Sweden in 2012 (annotated as 'obsoletus 01, 02, or 03 MA-2012') and of which some share a 99% identity with our sequences for 'dark obsoletus'. Without doubt, the series from the Netherlands, along with a portion of the Swedish submissions, together represent a single species ('dark obsoletus'). Whether this species is referable to the Russian Culicoides gornostaevae Mirzaeva recorded recently from Norway, Sweden and Poland, and based solely upon the external morphology of the male, is not clear. The presence in Western Europe of multiple undescribed species related to C. obsoletus means that the taxonomy of this important vector complex is not fully resolved; consequently, we know little about these cryptic species with regard to seasonality, geographic range and host preference. This is undesirable given that Culicoides-borne arboviruses causing disease in livestock are moving more regularly out of the tropics and spreading north into temperate latitudes. PMID:25583356

Meiswinkel, R; De Bree, F; Bossers-De Vries, R; Elbers, A R W

2015-01-30

318

Roaring High and Low: Composition and Possible Functions of the Iberian Stag's Vocal Repertoire  

PubMed Central

We provide a detailed description of the rutting vocalisations of free-ranging male Iberian deer (Cervus elaphus hispanicus, Hilzheimer 1909), a geographically isolated and morphologically differentiated subspecies of red deer Cervus elaphus. We combine spectrographic examinations, spectral analyses and automated classifications to identify different call types, and compare the composition of the vocal repertoire with that of other red deer subspecies. Iberian stags give bouts of roars (and more rarely, short series of barks) that are typically composed of two different types of calls. Long Common Roars are mostly given at the beginning or at the end of the bout, and are characterised by a high fundamental frequency (F0) resulting in poorly defined formant frequencies but a relatively high amplitude. In contrast, Short Common Roars are typically given in the middle or at the end of the bout, and are characterised by a lower F0 resulting in relatively well defined vocal tract resonances, but low amplitude. While we did not identify entirely Harsh Roars (as described in the Scottish red deer subspecies (Cervus elaphus scoticus)), a small percentage of Long Common Roars contained segments of deterministic chaos. We suggest that the evolution of two clearly distinct types of Common Roars may reflect divergent selection pressures favouring either vocal efficiency in high pitched roars or the communication of body size in low-pitched, high spectral density roars highlighting vocal tract resonances. The clear divergence of the Iberian red deer vocal repertoire from those of other documented European red deer populations reinforces the status of this geographical variant as a distinct subspecies. PMID:23667678

Carranza, Juan; Apollonio, Marco

2013-01-01

319

Environmental Drivers of Culicoides Phenology: How Important Is Species-Specific Variation When Determining Disease Policy?  

PubMed Central

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

320

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