| endocrine changes in photostimulated willow ptarmigan (lagopus lagopus lagopus) and svalbard ptarmigan (lagopus mutus hyperboreus). | changes in plasma luteinizing hormone (lh), testosterone, thyroxine (t4), and triiodothyronine (t3) and the height of supraorbital combs were compared in captive willow ptarmigan (lagopus lagopus lagopus) and svalbard ptarmigan (lagopus mutus hyperboreus) exposed to an artificial annual cycle of daylength simulating that at 70 degrees n. plasma lh and testosterone and comb height increased more slowly in svalbard than in willow ptarmigan as daylength increased. in both species, plasma lh and tes ... | 1988 | 3371650 |
| endocrine changes associated with fat deposition and mobilization in svalbard ptarmigan (lagopus mutus hyperboreus). | plasma concentrations of triiodothyronine (t3), thyroxine (t4) and growth hormone (gh) have been measured in blood samples taken from svalbard ptarmigans (lagopus mutus hyperboreus), shot throughout 1 whole year at svalbard (79 degrees n). plasma t3 levels varied in a monophasic pattern with low levels in winter and a peak in august, whereas plasma t4 levels remained constant throughout the year. high plasma t3 levels coincide with molt and a large food intake while low plasma levels of t3 coinc ... | 1985 | 3988037 |
| orienting and freezing responses in incubating ptarmigan hens. | behavior studies and telemetric recordings of heart and respiration rates were performed on five wild and two captive, incubating, willow ptarmigan hens (lagopus lagopus lagopus) and on four wild, incubating, svalbard ptarmigan hens (lagopus mutus hyperboreus). sounds and sight of approaching humans, egg predators, or dogs near the nests elicited behavior in the hens which we have interpreted as an orienting response (or) followed by freezing behavior. during both types of behavioral responses, ... | 1985 | 4059382 |
| [bacteria flora of feces of lagopus mutus japonicus in mt. tateyama]. | | 1971 | 4948731 |
| the response of three grouse species (tetrao urogallus, lagopus mutus, lagopus lagopus) to louping-ill virus. | | 1980 | 6253539 |
| persistent organochlorine levels in six prey species of the gyrfalcon falco rusticolus in iceland. | 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 platyrhyn ... | 2001 | 11234542 |
| leucocytozoon lovati infections in wild rock ptarmigan (lagopus mutus) in japan. | leucocytozoon lovati infections were detected in free-flying rock ptarmigan (lagopus mutus), an endangered species that inhabits alpine areas in japan. eight of nine adult birds tested positive for l. lovati infection. for comparison, two captive rock ptarmigans hatched in a breeding facility at the foot of the mountains were examined. both were negative for l. lovati infection. this is the first report of l. lovati infection in the rock ptarmigan in japan. | 2004 | 15650105 |
| lead concentrations in ruffed grouse, rock ptarmigan, and willow ptarmigan in québec. | between 1996 and 1998, ruffed grouse, spruce grouse, willow ptarmigan, and rock ptarmigan harvested by hunters in québec were examined for lead contamination. on examination of the gizzards of these birds, lead shot was found only in ruffed grouse (1.2%). the probability of ingestion of lead shot by grouse and ptarmigans is low. analyses of the lead concentrations in the wing bones of grouse and ptarmigans and in the muscle tissue of ptarmigans were conducted. although differences were observed ... | 2005 | 15959706 |
| phylogenetic comparison of leucocytozoon spp. from wild birds of japan. | eight species of japanese birds were found to be infected with leucocytozoon species using microscopic analysis. we used pcr and sequence analysis of the mitochondrial cytochrome b gene (cyt b) to compare the genetic background among these detected protozoa species. in 20 individuals of 22 samples, a single amplified band was detected from 6 of 8 bird species; 9 japanese rock ptarmigans (lagopus mutus japonicus), 4 large-billed crows (corvus macrorhynchos), 2 carrion crows (c. corone), 2 scops o ... | 2007 | 17283401 |
| geographical distribution and seasonality of the prevalence of leucocytozoon lovati in japanese rock ptarmigans (lagopus mutus japonicus) found in the alpine regions of japan. | in this study, we investigated the geographical distribution and seasonality of leucocytozoon lovati infection in the japanese rock ptarmigan (lagopus mutus japonicus); this bird is one of the special natural monuments of japan that inhabits the japanese alpine regions. we examined blood samples from birds captured in the kubiki, hida, and akaishi mountain ranges for three years from 2002 to 2005. seventy-three blood samples from 42 males, 19 females, and 12 birds of unknown sex were used for th ... | 2007 | 17339762 |
| two new eimeria species (protozoa: eimeriidae) from wild rock ptarmigans, lagopus muta islandorum, in iceland. | one hundred rock ptarmigans, lagopus muta islandorum (faber, 1822), were collected in early october 2006 in northeastern iceland and examined for coccidian parasites. two eimeria species were identified, and each is described as a new species. sporulated oocysts of one species are ellipsoidal, 24.9 x 16.6 (19.5-30 x 14.5-19) microm. oocysts have a small micropyle and a two-layered, smooth wall approximately 1.0 microm thick. an oocyst residuum is absent, but one to three polar granules are prese ... | 2007 | 17557155 |
| molecular detection of leucocytozoon lovati from probable vectors, black flies (simuliudae) collected in the alpine regions of japan. | probable arthropod vectors of avian blood protozoa, leucocytozoon lovati, were collected in the alpine regions of japan, the habitats of the host birds of japanese rock ptarmigan (lagopus mutus japonicus). seven alpine regions of japan, asahidake, chogatake, tateyama, jiigatake, norikura, kitadake, and senjyogatake were investigated for black fly collection during 2004 to 2007. the collected 490 insects were morphologically identified as six species of female black flies, including prosimulium h ... | 2009 | 18791737 |
| monitoring of raptors and their contamination levels in norway. | this article summarizes results from raptor monitoring and contamination studies in norway of the golden eagle, gyrfalcon, white-tailed sea eagle, osprey, peregrine, and merlin. golden eagle and gyrfalcon populations have been monitored since 1990 as part of the "monitoring programme for terrestrial ecosystems" (tov). no long-term trend in the population size or productivity of golden eagle has been shown in any of the 5 study areas. the reproductive output of gyrfalcon is monitored in 3 areas. ... | 2008 | 18833794 |
| molecular identification of blood source animals from black flies (diptera: simuliidae) collected in the alpine regions of japan. | one of vector-borne avian protozoa, leucocytozoon lovati, has been found in the japanese rock ptarmigans (lagopus mutus japonicus), the endangered bird species distributed in the alpine regions in japan. vector arthropod species of l. lovati has also been estimated as simuliidae black flies distributed in the same habitat of the host bird, however, possible blood meals of the black flies were not identified yet. to reveal host animals of black flies, we estimated the blood resources by using mol ... | 2010 | 19936792 |
| feather mites (astigmata: psoroptidia) parasitising the rock ptarmigan lagopus muta (montin) (aves: galliformes) in iceland. | four new species of feather mites are described from the icelandic rock ptarmigan lagopus muta islandorum (faber) in iceland. these are metamicrolichus islandicus n. sp., myialges borealis n. sp. (epidermoptidae), strelkoviacarus holoaspis n. sp. (analgidae) and tetraolichus lagopi n. sp. (pterolichidae). this is the first report on feather mites associated with the icelandic rock ptarmigan. brief comments on the systematics and biology of corresponding feather mite genera are given. for two spe ... | 2010 | 20157794 |
| description of the life stages of quill mite mironovia lagopus sp. nov. (acari: syringophilidae) parasitizing the rock ptarmigan lagopus muta (phasianidae) from iceland. | 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 t ... | 2010 | 20978793 |
| isolation of streptococcus gallolyticus with very high degradability of condensed tannins from feces of the wild japanese rock ptarmigans on mt. tateyama. | | 2017 | 28392540 |
| host-parasite interactions and population dynamics of rock ptarmigan. | populations of rock ptarmigan (lagopus muta) in iceland fluctuate in multiannual cycles with peak numbers c. every 10 years. we studied the ptarmigan-parasite community and how parasites relate to ptarmigan age, body condition, and population density. we collected 632 ptarmigan in northeast iceland in early october from 2006 to 2012; 630 (99.7%) were infected with at least one parasite species, 616 (98%) with ectoparasites, and 536 (85%) with endoparasites. we analysed indices for the combined p ... | 2016 | 27870855 |
| parasites and scottish ptarmigan numbers. | unlike red grouse (lagopus lagopus scoticus), which have almost 100% prevalence of the parasitic threadworm trichostrongylus tenuis and frequently high tapeworm numbers, 70% (n=71) of scottish ptarmigan (lagopus mutus) had no threadworms and only 4% had tapeworms. other parasites and pathogenic bacteria were infrequent. threadworms occurred in 12% (n=25) of birds on granite hills where mean ptarmigan densities were low, and in 43% (n=46) of birds over schists and limestones where mean densities ... | 1991 | 28313796 |
| herbivores influence the growth, reproduction, and morphology of a widespread arctic willow. | 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 ... | 2014 | 25047582 |
| virological investigation of avian influenza virus on postglacial species of phasianidae and tetraonidae in the italian alps. | 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 helveti ... | 2013 | 24167732 |
| the long term response of birds to climate change: new results from a cold stage avifauna in northern england. | the early mis 3 (55-40 kyr bp associated with middle palaeolithic archaeology) bird remains from pin hole, creswell crags, derbyshire, england are analysed in the context of the new dating of the site's stratigraphy. the analysis is restricted to the material from the early mis 3 level of the cave because the upper fauna is now known to include holocene material as well as that from the late glacial. the results of the analysis confirm the presence of the taxa, possibly unexpected for a late ple ... | 2015 | 25992609 |
| the digestion of bulbils (polygonum viviparum l.) and berries (vaccinium myrtillus l. and empetrum sp.) by captive ptarmigan (lagopus mutus). | 1. the digestion of three foods favoured by ptarmigan (lagopus mutus) in the wild was studied using captive birds. 2. bulbils of polygonum viviparum l. were a good source of metabolizable energy, protein and phosphorus, but were deficient in sodium. berries of vaccinium myrtillus l. were the most digestible of the three foods, contained enough protein and p for maintenance, but were probably deficient in na. a diet of empetrum sp. berries caused the birds to be in negative nitrogen and p balance ... | 1975 | 1167787 |
| historical biogeography and a mitochondrial dna phylogeny of grouse and ptarmigan. | 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 co ... | 2001 | 11421655 |
| bald eagles and sea otters in the aleutian archipelago: indirect effects of trophic cascades. | 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 nea ... | 2008 | 18959310 |
| occurrence of mesocestoides canislagopodis (rudolphi, 1810) (krabbe, 1865) in mammals and birds in iceland and its molecular discrimination within the mesocestoides species complex. | the life cycle of mesocestoides tapeworms (cestoda: cyclophyllidea: mesocestoididae) requires three hosts. the first intermediate host is unknown but believed to be an arthropod. the second intermediate host is a vertebrate. the primary definitive host is a carnivore mammal, or a bird of prey, that eats the tetrathyridium-infected second intermediate host. one representative of the genus, mesocestoides canislagopodis, has been reported from iceland. it is common in the arctic fox (vulpes lagopus ... | 2016 | 26984208 |
| population limitation in a non-cyclic arctic fox population in a changing climate. | arctic foxes vulpes lagopus (l.) display a sharp 3- to 5-year fluctuation in population size where lemmings are their main prey. in areas devoid of lemmings, such as iceland, they do not experience short-term fluctuations. this study focusses on the population dynamics of the arctic fox in iceland and how it is shaped by its main prey populations. hunting statistics from 1958-2003 show that the population size of the arctic fox was at a maximum in the 1950s, declined to a minimum in the 1970s, a ... | 2016 | 26714829 |
| transport characteristics and morphology of the colon and coprodeum in two wild birds of different habitats, the rock ptarmigan (lagopus mutus) and the common murre (uria aalge). | dietary salt intake in domestic fowl affects epithelial transport and morphology of the lower intestine (colon and coprodeum). this study investigated lower intestinal morphology and transport activity in two wild bird species with natural diets containing either low or high salt. tissues from rock ptarmigan (lagopus mutus) and common murres (uria aalge) were sampled for histology and electrophysiological analyses. the ptarmigan exists on a low salt diet, while the murre lives on a high protein ... | 2015 | 25937620 |
| morphological characteristics of mesocestoides canislagopodis (krabbe 1865) tetrathyridia found in rock ptarmigan (lagopus muta) in iceland. | necropsies of 1010 rock ptarmigans (lagopus muta) sampled in autumn 2006-2015 in northeast iceland revealed mesocestoides canislagopodis tetrathyridia infections in six birds (0.6 %), two juvenile birds (3 month old), and four adult birds (15 months or older). four birds had tetrathyridia in the body cavity, one bird in the liver, and one bird both in the body cavity and the liver. there were more tetrathyridia in the body cavity of the two juveniles (c. 50 in each) than in three adults (10-40), ... | 2016 | 27117162 |
| coevolution can reverse predator-prey cycles. | a hallmark of lotka-volterra models, and other ecological models of predator-prey interactions, is that in predator-prey cycles, peaks in prey abundance precede peaks in predator abundance. such models typically assume that species life history traits are fixed over ecologically relevant time scales. however, the coevolution of predator and prey traits has been shown to alter the community dynamics of natural systems, leading to novel dynamics including antiphase and cryptic cycles. here, using ... | 2014 | 24799689 |
| range shifts or extinction? ancient dna and distribution modelling reveal past and future responses to climate warming in cold-adapted birds. | global warming is predicted to cause substantial habitat rearrangements, with the most severe effects expected to occur in high-latitude biomes. however, one major uncertainty is whether species will be able to shift their ranges to keep pace with climate-driven environmental changes. many recent studies on mammals have shown that past range contractions have been associated with local extinctions rather than survival by habitat tracking. here, we have used an interdisciplinary approach that com ... | 2017 | 27762483 |
| cadmium concentrations in tissues of willow ptarmigan (lagopus lagopus) and rock ptarmigan (lagopus muta) in nunavik, northern québec. | willow and rock ptarmigan were obtained from northern québec. willow ptarmigan were found to have mean cadmium concentrations of 179.7 microg/g (dw) in the kidneys and 25.8 microg/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 in birds. the difference between the two ptarmigan species in cadmium content is explained by the diet. a comparison ... | 2007 | 17223236 |
| pulmonary phycomycosis in captive rock ptarmigan (lagopus mutus) and willow ptarmigan (lagopus lagopus) chicks. | | 1975 | 1136901 |
| variation in the visceral characteristics of the willow ptarmigan (lagopus albus) and common ptarmigan (lagopus mutus) in the taimir peninsula. | | 1974 | 4843924 |
| influence of life history strategies on sensitivity, population growth and response to climate for sympatric alpine birds. | the life history strategy of a species can influence how populations of that species respond to environmental variation. in this study, we used a matrix modeling approach to examine how life history differences among sympatric rock and white-tailed ptarmigan affect the influence of demographic rates on population growth (λ) and the potential response to a changing climate. rock ptarmigan have a slower life history strategy than white-tailed ptarmigan in the study region with lower annual reprodu ... | 2012 | 22747571 |
| climate change will seriously impact bird species dwelling above the treeline: a prospective study for the italian alps. | high mountain systems are predicted to be especially vulnerable to the impact of climate change, with the climatically-constrained tree limit rapidly shifted upslope. in turn, the impact of upward treeline migration on mountain-dwelling bird species is expected to significantly reduce habitat suitability. we developed the first projection of the expected climate-driven rise of the whole treeline (19,256km) of the italian alps. the study area extends over 20,700km(2), ranging over 550km in longit ... | 2017 | 28284643 |
| factors affecting diet variation in the pyrenean rock ptarmigan (lagopus muta pyrenaica): conservation implications. | the pyrenean rock ptarmigan (lagopus muta pyrenaica) lives at one of the southernmost limits of the ptarmigan range. their small population sizes and the impacts of global changes are limiting factors in the conservation of this threatened subspecies. an effective conservation policy requires precise basic knowledge of a species' food and habitat requirements, information that is practically non-existent for this pyrenean population. here, we describe the diet of a ptarmigan population in the ea ... | 2016 | 26863532 |
| influence of snowmelt timing on the diet quality of pyrenean rock ptarmigan (lagopus muta pyrenaica): implications for reproductive success. | the pyrenean rock ptarmigan (lagopus muta pyrenaica) is the southernmost subspecies of the species in europe and is considered threatened as a consequence of changes in landscape, human pressure, climate change, and low genetic diversity. previous studies have shown a relationship between the date of snowmelt and reproductive success in the pyrenean ptarmigan. it is well established that birds laying early in the breeding season have higher reproductive success, but the specific mechanism for th ... | 2016 | 26849356 |
| looking into the past - the reaction of three grouse species to climate change over the last million years using whole genome sequences. | tracking past population fluctuations can give insight into current levels of genetic variation present within species. analysing population dynamics over larger timescales can be aligned to known climatic changes to determine the response of species to varying environments. here, we applied the pairwise sequentially markovian coalescent (psmc) model to infer past population dynamics of three widespread grouse species; black grouse, willow grouse and rock ptarmigan. this allowed the tracking of ... | 2016 | 26607571 |
| cecal bacterial communities in wild japanese rock ptarmigans and captive svalbard rock ptarmigans. | preservation of indigenous gastrointestinal microbiota is deemed to be critical for successful captive breeding of endangered wild animals, yet its biology is poorly understood. here, we investigated cecal bacterial communities in wild japanese rock ptarmigans (lagopus muta japonica) and compared them with those in svalbard rock ptarmigans (l. m. hyperborea) in captivity. ultra-deep sequencing of 16s rrna gene indicated that the community structure of cecal microbiota in wild rock ptarmigans was ... | 2016 | 26468217 |
| the effects of season and sex upon the morphology and material properties of keratin in the svalbard rock ptarmigan (lagopus muta hyperborea). | 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 ( ... | 2014 | 25086983 |
| seasonal differences in jump performance in the svalbard rock ptarmigan (lagopus muta hyperborea). | 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 aro ... | 2014 | 24659246 |
| climate change and human disturbance can lead to local extinction of alpine rock ptarmigan: new insight from the western italian alps. | alpine grouses are particularly vulnerable to climate change due to their adaptation to extreme conditions and to their relict distributions in the alps where global warming has been particularly marked in the last half century. grouses are also currently threatened by habitat modification and human disturbance, and an assessment of the impact of multiple stressors is needed to predict the fate of alpine populations of these birds in the next decades. we estimated the effect of climate change an ... | 2013 | 24260581 |
| pyrenean ptarmigans decline under climatic and human influences through the holocene. | 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 diversi ... | 2013 | 23838689 |
| 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. | 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 ... | 2013 | 23264484 |
| glomerular lipidosis accompanied by renal tubular oxalosis in wild and laboratory-reared japanese rock ptarmigans (lagopus mutus japonicus). | 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. ... | 2011 | 22312998 |
| understanding sex differences in the cost of terrestrial locomotion. | 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 ... | 2012 | 21849317 |
| evidence for energy savings from aerial running in the svalbard rock ptarmigan (lagopus muta hyperborea). | 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 ... | 2011 | 21288943 |
| reduced metabolic cost of locomotion in svalbard rock ptarmigan (lagopus muta hyperborea) during winter. | 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, ... | 2010 | 21125015 |
| two eimeria species isolated from wild japanese rock ptarmigans (lagopus mutus japonicus) in japan. | fecal samples were collected from 64 japanese rock ptarmigans (lagopus mutus japonicus) at 13 locations in the alpine zone of japan and examined for internal parasites. we found 2 morphologically different types of eimerian oocysts. based on morphological characteristics, one was identified as eimeria uekii, which had already been found from japanese rock ptarmigans in 1981, and the other was likely a new type of eimeria. the new type of eimerian oocysts required a longer sporulation time than e ... | 2006 | 17019072 |
| glomerulopathy with renal tubular oxalosis in japanese rock ptarmigan (lagopus mutus). | seven adult japanese rock ptarmigan (lagopus mutus) that died on a rearing farm and appeared to have suffered from glomerulopathy with renal tubular oxalosis were examined pathologically. macroscopically, the kidneys showed enlargement of varying degrees. histologically, the precipitation of a fibril-like substance in the mesangial area of the renal glomeruli was the most important and common lesion seen in the kidney. calcification of glomeruli was observed in severe cases. in addition, oxalate ... | 2005 | 16236572 |
| population genetic structure of rock ptarmigan lagopus mutus in northern and western europe. | alpine species may be losing habitat because of global warming. setting management priorities for such species is thus urgent and cannot be achieved without data on population structure. we studied the structure of rock ptarmigan (lagopus mutus) populations in the pyrenees, alps and norway, using six microsatellites. we found that rock ptarmigan in the pyrenees were genetically impoverished compared with those in the alps and norway, and displayed a greater divergence (pyrenees vs. alps or norwa ... | 2003 | 12859645 |
| glacial vicariance and historical biogeography of rock ptarmigan (lagopus mutus) in the bering region. | in this paper, we address alternative hypotheses for the evolution of subspecies of rock ptarmigan (lagopus mutus) endemic to the aleutian archipelago. to do this we examined patterns of genetic differentiation among populations of rock ptarmigan in the aleutian islands and parts of both alaska and siberia. variation in mitochondrial control region sequences of 105 rock ptarmigan from 10 subspecies within the bering region revealed three major phylogenetic lineages, two of which are endemic to t ... | 2000 | 10972767 |
| a test of the glacial refugium hypothesis using patterns of mitochondrial and nuclear dna sequence variation in rock ptarmigan (lagopus mutus). | the glacial refugium hypothesis (grh) proposes that glaciers promoted differentiation and generation of intraspecific diversity by isolating populations in ice-free refugia. we tested three predictions of this hypothesis for the evolutionary divergence of rock ptarmigan (lagopus mutus) during the wisconsin glaciation of the late pleistocene. to do this, we examined subspecies distributions, population genetic structure, and phylogenetic relationships in 26 populations across north america and th ... | 1999 | 28565471 |
| seasonal and daily variations in plasma melatonin in the high-arctic svalbard ptarmigan (lagopus mutus hyperboreus). | this study presents the daily rhythm of melatonin secretion throughout one year in a bird from the northern hemisphere, the svalbard ptarmigan (lagopus mutus hyperboreus), which lives naturally at 76-80 degrees n. eight svalbard ptarmigan were caged outdoors at 70 degrees n and blood sampled throughout one day each month for 13 months. at this latitude, daylight is continuous between may and august, but there is a short period of civil twilight around noon from late november to mid january. ther ... | 1999 | 10447312 |
| dual entrainment by light and food in the svalbard ptarmigan (lagopus mutus hyperboreus). | the possibility that feeding may act as a zeitgeber has been investigated in captive svalbard ptarmigan by recording feeding or food-searching activity (fa) in birds given periodic access to food (paf) under light-dark (ld) cycles or in continuous bright (ll) or dim light (dd) conditions. except during ll, anticipatory attempts to feed always occurred prior to the food access interval with a relatively stable phase relationship to the interval. there was always a second bout of feeding toward th ... | 1998 | 9783230 |
| food intake, feeding rhythm, and body mass regulation in svalbard rock ptarmigan. | food intake (fi), feeding activity (fa), and body mass (bm) were recorded continuously throughout a 13-mo period in svalbard rock ptarmigan kept under natural conditions of light and ambient temperature at svalbard (79 degrees n). fi was persistently high from march until august, including the period when daylight is continuous, whereas it was low from november until january, when it is permanently dark. from august until november, bm doubled, while fi dropped to one-third. bm fell rapidly from ... | 1986 | 3740307 |
| the annual breeding cycle of the high-arctic svalbard ptarmigan (lagopus mutus hyperboreus). | gonadal size, spermatogenesis, egg production, height of the supraorbital comb, moult, and plasma luteinizing hormone (lh) levels were measured during an annual cycle in wild svalbard ptarmigans (lagopus mutus hyperboreus). these birds live permanently at 77-81 degrees n where daylight is continuous from the beginning of april until mid september while the average ambient temperature is above freezing only between early june and mid september. the gonads and comb size began to enlarge in march c ... | 1986 | 3956996 |
| methane production in rock ptarmigan (lagopus mutus). | | 1976 | 4267 |
| cellulose digestion and metabolism by captive rock ptarmigan. | | 1976 | 4266 |
| blood parasites in rock ptarmigan from eagle summit, alaska. | | 1967 | 4965717 |
| canines (canis lupus familiaris) as biodetectors for conservation work: can they discriminate the rock ptarmigan (lagopus muta) from the willow grouse (l. lagopus) in a yes/no task? | alpine and arctic bird populations have shown an unmistakable decrease over the last three decades, and the need for conservation is highly necessary. we investigated the use of five privately-owned dogs (canis lupus familiaris) as a non-invasive tool to determine the presence of rock ptarmigan (lagopus muta), through sniffing out faecal pellets, using a yes/no training regime. we carried out 36 double-blind experimental trials per dog and hypothesised that dogs could discriminate the rock ptarm ... | 2020 | 31990940 |
| limited dietary overlap amongst resident arctic herbivores in winter: complementary insights from complementary methods. | snow may prevent arctic herbivores from accessing their forage in winter, forcing them to aggregate in the few patches with limited snow. in high arctic greenland, arctic hare and rock ptarmigan often forage in muskox feeding craters. we therefore hypothesized that due to limited availability of forage, the dietary niches of these resident herbivores overlap considerably, and that the overlap increases as winter progresses. to test this, we analyzed fecal samples collected in early and late wint ... | 2018 | 29700632 |
| dietary variation in icelandic arctic fox (vulpes lagopus) over a period of 30 years assessed through stable isotopes. | identifying resources driving long-term trends in predators is important to understand ecosystem changes and to manage populations in the context of conservation or control. the arctic fox population in iceland has increased steadily over a period of 30 years, an increase that has been attributed to an overall increase in food abundance. we hypothesized that increasing populations of geese or seabirds were driving this growth. we analyzed stable isotopes in a long-term series of collagen samples ... | 2020 | 31865484 |
| gastroenteric parasite of wild galliformes in the italian alps: implication for conservation management. | this study provides insights about the diversity, prevalence and distribution of alpine wild galliformes gastrointestinal parasite community, trying to fill a gap in the scientific information currently available in scientific literature. the analysis included three host species: 77 rock partridge (alectoris graeca saxatilis), 83 black grouse (tetrao tetrix tetrix) and 26 rock ptarmigan (lagopus muta helveticus) shot during the hunting seasons 2008-2015. parasites isolated were ascaridia compar, ... | 2020 | 31852557 |
| past and potential future population dynamics of three grouse species using ecological and whole genome coalescent modeling. | studying demographic history of species provides insight into how the past has shaped the current levels of overall biodiversity and genetic composition of species, but also how these species may react to future perturbations. here we investigated the demographic history of the willow grouse (lagopus lagopus), rock ptarmigan (lagopus muta), and black grouse (tetrao tetrix) through the late pleistocene using two complementary methods and whole genome data. species distribution modeling (sdm) allo ... | 2018 | 30038766 |
| molecular identification of two eimeria species, e. uekii and e. raichoi as type b, in wild japanese rock ptarmigans, lagopus muta japonica. | thus far, two types of eimeria parasites (e. uekii and type b) have been morphologically identified in wild japanese rock ptarmigans, lagopus muta japonica. although high prevalences were reported for these parasites, genetic analyses have not been conducted. we first clarified the phylogenetic positions of two eimerian isolates using genetic analyses of 18s rrna and mitochondrial cytochrome c oxidase subunit i gene regions. consequently, of 61 samples examined, 21 and 11 samples were positive f ... | 2018 | 29988940 |
| circumpolar status of arctic ptarmigan: population dynamics and trends. | rock ptarmigan (lagopus muta) and willow ptarmigan (l. lagopus) are arctic birds with a circumpolar distribution but there is limited knowledge about their status and trends across their circumpolar distribution. here, we compiled information from 90 ptarmigan study sites from 7 arctic countries, where almost half of the sites are still monitored. rock ptarmigan showed an overall negative trend on iceland and greenland, while svalbard and newfoundland had positive trends, and no significant tren ... | 2020 | 31073984 |
| development and evaluation of 16 new microsatellite loci for the rock ptarmigan (lagopus muta) and cross-species amplification for the willow grouse (l. lagopus). | the genetic markers designed for this study can facilitate future genetic studies on the rock ptarmigan (lagopus muta). to our knowledge no microsatellite markers have ever been developed specifically for this species before. these new microsatellite markers will be useful for population genetics studies and for future conservation projects. | 2018 | 29463303 |
| photoperiodic induction without light-mediated circadian entrainment in a high arctic resident bird. | organisms use changes in photoperiod to anticipate and exploit favourable conditions in a seasonal environment. while species living at temperate latitudes receive day length information as a year-round input, species living in the arctic may spend as much as two-thirds of the year without experiencing dawn or dusk. this suggests that specialised mechanisms may be required to maintain seasonal synchrony in polar regions. svalbard ptarmigan (lagopus muta hyperborea) are resident at 74-81°n latitu ... | 2020 | 32587064 |
| metabolomic lc-ms/ms analyses and meta 16s rrna gene analyses on cecal feces of japanese rock ptarmigans reveal fundamental differences between semi-wild and captive raised individuals. | ex situ conservation of japanese rock ptarmigans began in 2015 with the aim of reintroducing artificially raised birds into their original habitat. however, the current raising method in captivity seems insufficient in terms of the survivability of artificially raised birds in natural conditions. feeding management is one potential reason for such insufficiency. in this study, we performed a comprehensive analysis of the hydrophilic metabolites by lc-ms/ms for the cecal feces of japanese rock pt ... | 2020 | 32581149 |
| parasitic development in intestines and oocyst shedding patterns for infection by eimeria uekii and eimeria raichoi in japanese rock ptarmigans, lagopus muta japonica, protected by cages in the southern japanese alps. | the population of japanese rock ptarmigan (lagopus muta japonica), an endangered species with a habitat above the timberline of the southern japanese alps, has declined. as one of the recent conservation strategies for this species, cage protection for broods (hens and chicks) has been introduced in their habitats. two species of eimeria have frequently been detected in these birds, but little is known about the parasitic circulation in the region, including among birds and in the environment. h ... | 2020 | 32368488 |
| reduced immune responsiveness contributes to winter energy conservation in an arctic bird. | animals in seasonal environments must prudently manage energy expenditure to survive the winter. this may be achieved through reductions in the allocation of energy for various purposes (e.g. thermoregulation, locomotion, etc.). we studied whether such trade-offs also include suppression of the innate immune response, by subjecting captive male svalbard ptarmigan (lagopus muta hyperborea) to bacterial lipopolysaccharide (lps) during exposure to either mild temperature (0°c) or cold snaps (acute ... | 2020 | 32341183 |
| gastrointestinal parasitic infestation in the rock ptarmigan lagopus muta in the french alps and french pyrenees based on long-term sampling (1987-2018). | data presented in this work represents the first record of parasites from the alpine and pyrenean lagopus muta subspecies, providing valuable information to consider for conservation management. from 1987 to 2018, 207 rock ptarmigans were collected in the framework of a long-term sanitary monitoring in france. eight parasites were found in the alpine rock ptarmigan, and one in the pyrenean subspecies. only two parasites occurred with high prevalence in the alpine rock ptarmigan: capillaria caudi ... | 2020 | 32234098 |
| isolation, synthesis, and biological activities of a bibenzyl from empetrum nigrum var. japonicum. | 4-(2-hydroxyphenethyl)-2,6-dimethoxyphenol, a bibenzyl, was isolated from the leaves of empetrum nigrum var. japonicum, collected from mount tateyama. japanese rock ptarmigans frequently eat the leaves and fruits of this plant. the structure of the bibenzyl was confirmed by nmr spectroscopic analysis and fully characterized. a synthesis of this compound was accomplished by coupling 2-hydroxyphenylacetic acid with syringaldehyde, decarboxylation of the resultant isoaurones, and hydrogenation of t ... | 2020 | 31794330 |
| role of coprophagy in the cecal microbiome development of an herbivorous bird japanese rock ptarmigan. | the transgenerational maintenance of symbiotic microbes that benefit host nutrition and health is evolutionarily advantageous. in some vertebrate lineages, coprophagy is used as a strategy for effectively transmitting microbes across generations. however, this strategy has still not been studied in birds. accordingly, the aim of the present study was to evaluate the role of maternal cecal feces consumption by japanese rock ptarmigan (lagopus muta japonica) chicks as a strategy for acquiring esse ... | 2019 | 31406033 |
| terrestrial locomotion of the svalbard rock ptarmigan: comparing field and laboratory treadmill studies. | research into the terrestrial locomotion of birds is often based upon laboratory treadmill experiments. however, it is unclear how transposable these results are for birds moving in the wild. here, using video recordings, we compared the kinematics of locomotion (stride frequency, stride length, stance phase, swing phase, duty factor) and speed range of svalbard rock ptarmigan (lagopus muta hyperborea) under field and laboratory treadmill conditions. our findings indicate that the kinematics of ... | 2019 | 31391515 |
| modeling future wildlife habitat suitability: serious climate change impacts on the potential distribution of the rock ptarmigan lagopus muta japonica in japan's northern alps. | the rock ptarmigan lagopus muta japonica lives in the alpine zones of central japan, which is the southern limit of the global distribution for this species. this species is highly dependent on alpine habitats, which are considered vulnerable to rapid climate change. this study aimed to assess the impact of climate change on potential l. muta japonica habitat based on predicted changes to alpine vegetation, to identify population vulnerability under future climatic conditions for conservation pl ... | 2019 | 31288795 |
| quill mite infestation of rock ptarmigan lagopus muta (aves: phasianidae) in relation to year and host age, sex, body condition, and density. | a total of 1209 ptarmigan were examined for mironovia lagopus, including 721 juvenile birds (ca. 3 months old) and 488 adult birds (15 months or older). a total of 88 birds or 7.3% (n = 1209, 95% cl 5.9-8.9%) were infested with m. lagopus. there was an age difference in prevalence of infection, and more adults (10.7%, n = 488, 95% cl 8.2-13.7%) than juveniles (5.0%, n = 721, 95% cl 3.6-6.8%) were infested. there was a significant age effect in the mean intensity index, and adult birds had more a ... | 2019 | 31278517 |
| ambient temperature effects on stress-induced hyperthermia in svalbard ptarmigan. | stress-induced hyperthermia (sih) is commonly observed during handling in homeotherms. however, in birds, handling in cold environments typically elicits hypothermia. it is unclear whether this indicates that sih is differently regulated in this taxon or if it is due to size, because body temperature changes during handling in low temperatures have only been measured in small birds <0.03 kg (that are more likely to suffer high heat loss when handled). we have therefore studied thermal responses ... | 2019 | 31182628 |
| island biogeography theory explains the genetic diversity of a fragmented rock ptarmigan (lagopus muta) population. | the island biogeography theory is one of the major theories in ecology, and its applicability to natural systems is well documented. the core model of the theory, the equilibrium model of island biogeography, predicts that species diversity on an island is positively related to the size of the island, but negatively related by the island's distance to the mainland. in recent years, ecologists have begun to apply this model when investigating genetic diversity, arguing that genetic and species di ... | 2019 | 31015970 |
| characterization of the cecum microbiome from wild and captive rock ptarmigans indigenous to arctic norway. | rock ptarmigans (lagopus muta) are gallinaceous birds inhabiting arctic and sub-arctic environments. their diet varies by season, including plants or plant parts of high nutritional value, but also toxic plant secondary metabolites (psms). little is known about the microbes driving organic matter decomposition in the cecum of ptarmigans, especially the last steps leading to methanogenesis. the cecum microbiome in wild rock ptarmigans from arctic norway was characterized to unveil their functiona ... | 2019 | 30856229 |
| predator-prey feedback in a gyrfalcon-ptarmigan system? | specialist predators with oscillating dynamics are often strongly affected by the population dynamics of their prey, yet they are not always the cause of prey cycling. only those that exert strong (delayed) regulation of their prey can be. inferring predator-prey coupling from time series therefore requires contrasting models with top-down versus bottom-up predator-prey dynamics. we study here the joint dynamics of population densities of the icelandic gyrfalcon falco rusticolus, and its prey, t ... | 2018 | 30619555 |
| cecal microbiome analyses on wild japanese rock ptarmigans (lagopus muta japonica) reveals high level of coexistence of lactic acid bacteria and lactate-utilizing bacteria. | preservation of indigenous gastrointestinal microbiota is critical for successful captive breeding of endangered wild animals, yet its biology is poorly understood. here, we compared the cecal microbial composition of wild living japanese rock ptarmigans (lagopus muta japonica) in different locations of japanese mountains, and the dominant cecal microbial structure of wild japanese rock ptarmigans is elucidated. coriobacteraceae and lachnospraceae were the two dominant bacterial families in all ... | 2018 | 30060588 |
| surveillance of eimeria species in wild japanese rock ptarmigans, lagopus muta japonica, and insight into parasitic seasonal life cycle at timberline regions of the japanese alps. | the japanese rock ptarmigan, lagopus muta japonica, inhabits the alpine zone of mountainous areas at 3000 m above sea level. since l. m. japonica is endangered due to a decline in the overall population, controlling infectious diseases such as those caused by protozoan parasites is a critical factor in the conservation of this species. although eimeria spp. are considered to have a negative impact on japanese rock ptarmigan populations, the ecological interactions between the parasites and their ... | 2018 | 29988830 |
| seasonal variation in the thermal responses to changing environmental temperature in the world's northernmost land bird. | arctic homeotherms counter challenges at high latitudes using a combination of seasonal adjustments in pelage/plumage, fat deposition and intricate thermoregulatory adaptations. however, there are still gaps in our understanding of their thermal responses to cold, particularly in arctic birds. here, we have studied the potential use of local heterothermy (i.e. tissue cooling that can contribute to significantly lower heat loss rate) in svalbard ptarmigan (lagopus muta hyperborea) - the world's n ... | 2018 | 29113988 |