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1.
Glob Chang Biol ; 24(3): 1136-1149, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28973826

RESUMEN

Climate change represents a primary threat to species persistence and biodiversity at a global scale. Cold adapted alpine species are especially sensitive to climate change and can offer key "early warning signs" about deleterious effects of predicted change. Among mountain ungulates, survival, a key determinant of demographic performance, may be influenced by future climate in complex, and possibly opposing ways. Demographic data collected from 447 mountain goats in 10 coastal Alaska, USA, populations over a 37-year time span indicated that survival is highest during low snowfall winters and cool summers. However, general circulation models (GCMs) predict future increase in summer temperature and decline in winter snowfall. To disentangle how these opposing climate-driven effects influence mountain goat populations, we developed an age-structured population model to project mountain goat population trajectories for 10 different GCM/emissions scenarios relevant for coastal Alaska. Projected increases in summer temperature had stronger negative effects on population trajectories than the positive demographic effects of reduced winter snowfall. In 5 of the 10 GCM/representative concentration pathway (RCP) scenarios, the net effect of projected climate change was extinction over a 70-year time window (2015-2085); smaller initial populations were more likely to go extinct faster than larger populations. Using a resource selection modeling approach, we determined that distributional shifts to higher elevation (i.e., "thermoneutral") summer range was unlikely to be a viable behavioral adaptation strategy; due to the conical shape of mountains, summer range was expected to decline by 17%-86% for 7 of the 10 GCM/RCP scenarios. Projected declines of mountain goat populations are driven by climate-linked bottom-up mechanisms and may have wide ranging implications for alpine ecosystems. These analyses elucidate how projected climate change can negatively alter population dynamics of a sentinel alpine species and provide insight into how demographic modeling can be used to assess risk to species persistence.


Asunto(s)
Cambio Climático , Rumiantes/fisiología , Alaska , Animales , Ecosistema , Modelos Biológicos , Dinámica Poblacional , Estaciones del Año
2.
Ecol Appl ; 28(5): 1131-1142, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29573503

RESUMEN

The niche concept provides a strong foundation for theoretical and applied research among a broad range of disciplines. When two ecologically similar species are sympatric, theory predicts they will occupy distinct ecological niches to reduce competition. Capitalizing on the increasing availability of spatial data, we built from single species habitat suitability models to a multispecies evaluation of the niche partitioning hypothesis with sympatric mountain ungulates: native bighorn sheep (BHS; Ovis canadensis) and introduced mountain goats (MTG; Oreamnos americanus) in the northeast Greater Yellowstone Area. We characterized seasonal niches using two-stage resource selection functions with a used-available design and descriptive summaries of the niche attributes associated with used GPS locations. We evaluated seasonal similarity in niche space according to confidence interval overlap of model coefficients and similarity in geographic space by comparing model predicted values with Schoener's D metric. Our sample contained 37,962 summer locations from 53 individuals (BHS = 31, MTG = 22), and 79,984 winter locations from 57 individuals (BHS = 35, MTG = 22). Slope was the most influential niche component for both species and seasons, and showed the strongest evidence of niche partitioning. Bighorn sheep occurred on steeper slopes than mountain goats in summer and mountain goats occurred on steeper slopes in winter. The pattern of differential selection among species was less prevalent for the remaining covariates, indicating similarity in niche space. Model predictions in geographic space showed broad seasonal similarity (summer D = 0.88, winter D = 0.87), as did niche characterizations from used GPS locations. The striking similarities in seasonal niches suggest that introduced mountain goats will continue to increase their spatial overlap with native bighorn. Our results suggest that reducing densities of mountain goats in hunted areas where they are sympatric with bighorn sheep and impeding their expansion may reduce the possibility of competition and disease transfer. Additional studies that specifically investigate partitioning at finer scales and along dietary or temporal niche axes will help to inform an adaptive management approach.


Asunto(s)
Ecosistema , Especies Introducidas , Rumiantes/fisiología , Animales , Femenino , Masculino , Estaciones del Año , Borrego Cimarrón/fisiología , Wyoming
3.
Parasitol Res ; 114(11): 4135-41, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26255900

RESUMEN

Numerous species of Sarcocystis have been reported from wild ruminants, but none has been named from the Rocky Mountain goat (Oreamnos americanus). Mature sarcocysts were found in frozen muscle samples of three of seven mountain goats from Alaska, USA. Two morphological types of sarcocysts were found; one had Sarcocystis cornagliai-like sarcocysts, previously named from the Alpine ibex (Capra ibex) from Europe. Two other goats were infected with a new species, Sarcocystis oreamni. Sarcocystis oreamni sarcocysts were microscopic with 2 µm-thick sarcocyst wall. By transmission electron microscopy, the sarcocyst wall had 1.7 µm-thick with unusual molar tooth-like villar protrusions (vp), type 29. The vp had an electron dense core and two disc-shaped plaques at the tip with fine microtubules. Bradyzoites were 8.6-9.1 µm long. Single nucleotide polymorphism (SNP) identified in 18S rRNA, and 28S rRNA loci of rDNA regions that suggested S. oreamni molecularly apart from related species. The phylogenetic analysis based on 18S rRNA and 28S rRNA sequences suggested S. oreamni is related with Sarcocystis species that employ members of the Canidae family as their definitive host.


Asunto(s)
Enfermedades de las Cabras/parasitología , Sarcocystis/aislamiento & purificación , Sarcocistosis/parasitología , Alaska , Animales , ADN Ribosómico/genética , Europa (Continente) , Cabras , Datos de Secuencia Molecular , Filogenia , Sarcocystis/clasificación , Sarcocystis/genética , Sarcocistosis/veterinaria
4.
Ecol Evol ; 11(16): 11051-11064, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34429902

RESUMEN

Understanding patterns of animal space use and range fidelity has important implications for species and habitat conservation. For species that live in highly seasonal environments, such as mountain goats (Oreamnos americanus), spatial use patterns are expected to vary in relation to seasonal changes in environmental conditions and sex- or age-specific selection pressures. To address hypotheses about sex, age, and seasonality influence on space-use ecology, we collected GPS location data from 263 radio-collared mountain goats (males, n = 140; females, n = 123) in coastal Alaska during 2005-2016. Location data were analyzed to derive seasonal and sex-specific fixed-kernel home range estimates and to quantify the degree of seasonal range and utilization distribution overlap. Overall, we determined that home range size was smallest during winter, expanded coincident with the onset of green-up and parturition, and was largest during summer. Home range size of males and females did not differ significantly during winter, but females had larger home ranges than males during summer, a relationship that was switched during the mating season. Pairwise comparisons involving individual females across subsequent years indicated home ranges were significantly smaller during years when they gave birth to offspring. Mountain goats exhibited a strong degree of range fidelity, and 99% (n = 138) of individual animals returned to their previous year's seasonal range with an average annual Bhattacharyya's affinity utilization distribution overlap index of 68%. Similarity of seasonal home range utilization distributions varied in relation to sex and season in some respects. Home range overlap was highest during the summer vegetation growing season, particularly among females. These findings advance our understanding about how environmental variation and sex- and age-related reproductive constraints influence space use and range fidelity among alpine ungulates. Documentation of the high degree of range fidelity among mountain goats has important conservation implications in landscapes increasingly altered by anthropogenic activities.

5.
FEMS Microbiol Ecol ; 97(5)2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33729507

RESUMEN

The gut microbiome of animals vary by age, diet, and habitat, and directly influences an individual's health. Similarly, variation in home ranges is linked to feeding strategies and fitness. Ungulates (hooved mammals) exhibit species-specific microbiomes and habitat use patterns. We combined gut microbiome and movement data to assess relationships between space use and the gut microbiome in a specialist and a generalist ungulate. We GPS radiocollared 24 mountain goats (Oreamnos americanus) and 34 white-tailed deer (Odocoileus virginianus), collected fecal samples, and conducted high-throughput sequencing of the 16S rRNA gene. We generated gut diversity metrics and key bacterial ratios. Our research question centred around the idea that larger Firmicutes to Bacteroidetes ratios confer body size or fat advantages that allow for larger home ranges, and relationships of disproportionate habitat use are stronger in the habitat specialist mountain goat. Firmicutes to Bacteroidetes ratios were positively correlated with core range area in both species. Mountain goats exhibited a negative relationship between gut diversity and proportional use of treed areas and escape terrain, and no relationships were detected in the habitat generalist white-tailed deer. This is the first study to relate range size to the gut microbiome in wild ungulates and is an important proof of concept that advances the information that can be gleaned from non-invasive sampling.


Asunto(s)
Ciervos , Microbioma Gastrointestinal , Animales , Heces , Firmicutes , ARN Ribosómico 16S/genética
6.
G3 (Bethesda) ; 10(2): 437-442, 2020 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-31806764

RESUMEN

The North American mountain goat (Oreamnos americanus) is an iconic alpine species that faces stressors from climate change, industrial development, and recreational activities. This species' phylogenetic position within the Caprinae lineage has not been resolved and their phylogeographic history is dynamic and controversial. Genomic data could be used to address these questions and provide valuable insights to conservation and management initiatives. We sequenced short-read genomic libraries constructed from a DNA sample of a 2.5-year-old female mountain goat at 80X coverage. We improved the short-read assembly by generating Chicago library data and scaffolding using the HiRise approach. The final assembly was 2,506 Mbp in length with an N50 of 66.6 Mbp, which is within the length range and in the upper quartile for N50 published ungulate genome assemblies. Comparative analysis identified 84 gene families unique to the mountain goat. The species demographic history in terms of effective population size generally mirrored climatic trends over the past one hundred thousand years and showed a sharp decline during the last glacial maximum. This genome assembly will provide a reference basis for future population and comparative genomic analyses.


Asunto(s)
Ambientes Extremos , Rumiantes/genética , Animales , Femenino , Genoma , Especificidad de la Especie
7.
PeerJ ; 8: e9296, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32566402

RESUMEN

Understanding relationships between animals and their habitat is a central goal in ecology with important implications for conservation. Misidentified habitat requirements can have serious repercussions because land protection or reintroductions might occur in less than optimal habitat. Studies of resource selection have greatly facilitated an understanding of ecological relationships but can be improved when vital yet infrequently utilized habitat features are more fully described. A critical element for many prey species is escape terrain or some other form of refuge to avoid predation. Mountain goats (Oreamnos americanus) are well known for their use of cliffs to avoid predation, but a survey of the literature revealed at least twelve different approximations of goat escape terrain, ranging from > 25° to > 50° slopes. Here, we seek to (1) enhance estimates of mountain goat escape terrain and antipredator behavior, and (2) highlight the limitations of the assumption that the time an animal spends in an area is proportional to importance. To improve estimates of goat escape terrain, we conducted field work across two years (2014-15) in Glacier National Park, Montana USA and manipulated apparent predation risk by exposing mountain goats to a threatening simulated grizzly bear (Ursus arctos) treatment and a non-threatening ungulate (control) treatment. Mountain goats moved in response to the simulated bear but not in response to the simulated ungulate, with shorter latencies to move for subjects in larger groups and at shorter distances to the simulated threat. Through a used-unused resource selection function we tested 22 landscape variables to describe the use of escape terrain. Proximity to slopes greater than 60° best explained the locations to which mountain goats fled after exposure to the simulated bear, and the average slope of these escape locations was 56.5° (±14.1 S.D.). Our results suggest that mountain goat escape terrain be considered at slopes of 60° as a minimum because our simulated threat did not include pursuit of goats and, thus, slopes of 60° are likely underestimates of actual escape terrain. Additionally, because direct interactions between carnivores and goats seldom occur, serious escape terrain is infrequently used. Past estimates of escape may have miscalculated the slopes which goats select for in response to predation risk. Based on experimental approaches in the wild, we suggest that anti-predator behavior should be included in studies of resource selection when the goal is to consider habitat as a predictor for conservation success. Finally, we discuss evidence suggesting a past mountain goat introduction failed due to lack of adequate escape terrain and subsequent recolonization of a predator.

8.
PeerJ ; 8: e9143, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32523807

RESUMEN

We investigated survival and cause-specific mortality for a mountain goat (Oreamnos americanus) population during a period when the puma (Puma concolor) population was growing in the Black Hills, South Dakota, 2006-2018. We obtained survival data from 47 adult goats (n = 33 females, n = 14 males). Annual survival varied from 0.538 (95% CI [0.285-0.773]) to 1.00 (95% CI [1.00-1.00]) and puma predation was the primary cause-specific mortality factor over a 12-year period. Cumulative hectares of mountain pine beetle (Dendroctonus ponderosae) disturbance was a covariate of importance (w i  = 0.972; ß = 0.580, 95% CI [0.302-0.859]) influencing survival. To our knowledge, this is the first account of puma being the primary mortality factor of mountain goats over a long-term study. The Black Hills system is unique because we could examine the expanded realized niche of puma in the absence of other large carnivores and their influence on mountain goats. We hypothesize that puma were being sustained at higher densities due to alternate prey sources (e.g., white-tailed deer; Odocoileous virginianus) and this small population of mountain goats was susceptible to predation by one or several specialized puma in the Black Hills. However, we also hypothesize a changing landscape with increased tree mortality due to insect infestation provided conditions for better predator detection by goats and increased survival. Alternatively, open canopy conditions may have increased understory forage production potentially increasing mountain goat survival but we did not evaluate this relationship. Survival and mortality rates of mountain goats should continue to be monitored as this small population may be highly susceptible to population declines due to slow growth rates.

9.
J Wildl Dis ; 55(1): 206-212, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30161017

RESUMEN

We documented bronchopneumonia in seven mountain goat ( Oreamnos americanus) kid mortalities between 2011 and 2015 following a pneumonia epizootic in bighorn sheep ( Ovis canadensis) and sympatric mountain goats in the adjacent East Humboldt Range and Ruby Mountains in Elko County, Nevada, US. Gross and histologic lesions resembled those described in bighorn lambs following all-age epizootics, and Mycoplasma ovipneumoniae was detected with real-time PCR in the lower and upper respiratory tracts of all kids. Mannheimia haemolytica, with one isolate being leukotoxigenic, was cultured from the upper respiratory tract of five kids, and in one kid, a leukotoxigenic strain of Mannheimia glucosida was isolated from both upper and lower respiratory tracts. During this same period, 75 mountain goats within the two populations were marked and sampled for respiratory pathogens, and M. ovipneumoniae, leukotoxigenic Bibersteinia trehalosi, and Mannheimia haemolytica were identified. The M. ovipneumoniae recovered from the kid mortalities shared the same DNA sequence-based strain type detected in the adult goats and sympatric bighorn sheep during and after the 2009-10 pneumonia outbreak. Clinical signs in affected kids, as well as decreased annual kid recruitment, also resembled reports in bighorn lambs from some herds following all-age pneumonia-associated die-offs. Mycoplasma ovipneumoniae, Pasteurellaceae spp., and other respiratory bacterial pathogens should be considered as a cause of pneumonia with potential population-limiting effects in mountain goats.


Asunto(s)
Mycoplasma ovipneumoniae/aislamiento & purificación , Neumonía por Mycoplasma/veterinaria , Rumiantes , Animales , Nevada/epidemiología , Neumonía por Mycoplasma/epidemiología , Neumonía por Mycoplasma/microbiología , Neumonía por Mycoplasma/mortalidad
10.
Ecol Evol ; 9(5): 2920-2932, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30891226

RESUMEN

Because growth of new hairs entails energetic costs, individual condition and access to food should determine the timing of molt. Previous studies on the timing of molt in ungulates have mostly focused on the influence of age class and reproductive status, but the effects of body condition and environmental phenology have not been evaluated. Our goal was to assess how intrinsic traits and environmental conditions determine the timing of winter coat shedding in a mountain goat population monitored for 27 years. The date of molt completion followed a U shape with age, suggesting that senescence occurs in terms of the molting process in mountain goats. Juveniles of both sexes delayed molting in a similar fashion, but molt timing differed between sexes during adulthood. Males molted progressively earlier until reaching age when reproduction peaked, after which they started delaying molting again. Females reached earliest molt dates at age of first reproduction and then progressively delayed molt date. Lactating females molted 10 days later than barren females on average, but this only occurred in females in good condition. Thus, although it has been shown that reproduction delays molt in ungulates, our results indicate that body condition can override this effect. Overall, our results revealed that access to both extrinsic and intrinsic resources is one of the key mechanisms driving molting processes in a mammalian herbivore.

11.
J Wildl Dis ; 54(4): 852-858, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29902131

RESUMEN

In contrast to broad range expansion through translocations, many mountain goat ( Oreamnos americanus) populations have shown signs of decline. Recent documentation of pneumonia in mountain goats highlights their susceptibility to bacterial pathogens typically associated with bighorn sheep ( Ovis canadensis) epizootics. Respiratory pathogen communities of mountain goats are poorly characterized yet have important implications for management and conservation of both species. We characterized resident pathogen communities across a range of mountain goat populations as an initial step to inform management efforts. Between 2010 and 2017, we sampled 98 individuals within three regions of the Greater Yellowstone Area (GYA), with a smaller sampling effort in southeast Alaska, US. Within the GYA, we detected Mycoplasma ovipneumoniae in two regions and we found at least two Pasteurellaceae species in animals from all regions. Mannheimia haemolytica was the only pathogen that we detected in southeast Alaska. Given the difficult sampling conditions, limited sample size, and imperfect detection, our failure to detect specific pathogens should be interpreted with caution. Nonetheless, respiratory pathogens within the GYA may be an important, yet underappreciated, cause of mountain goat mortality. Moreover, because of the strong niche overlap of bighorn sheep and mountain goats, interspecific transmission is an important concern for managers restoring or introducing mountain ungulates within sympatric ranges.


Asunto(s)
Bacterias/aislamiento & purificación , Infecciones Bacterianas/veterinaria , Infecciones del Sistema Respiratorio/veterinaria , Rumiantes/microbiología , Animales , Bacterias/clasificación , Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/microbiología , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/microbiología , Estados Unidos/epidemiología
12.
Acta Vet Scand ; 60(1): 12, 2018 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-29467004

RESUMEN

BACKGROUND: The zoonotic Orf virus (ORFV; genus Parapoxvirus, Poxviridae family) occurs worldwide and is transmitted between sheep and goats, wildlife and man. Archived tissue samples from 16 Alaskan wildlife cases, representing mountain goat (Oreamnos americanus, n = 8), Dall's sheep (Ovis dalli dalli, n = 3), muskox (Ovibos moschatus, n = 3), Sitka black-tailed deer (Odocoileus hemionus sitkensis, n = 1) and caribou (Rangifer tarandus granti, n = 1), were analyzed. RESULTS: Clinical signs and pathology were most severe in mountain goats, affecting most mucocutaneous regions, including palpebrae, nares, lips, anus, prepuce or vulva, as well as coronary bands. The proliferative masses were solid and nodular, covered by dark friable crusts. For Dall's sheep lambs and juveniles, the gross lesions were similar to those of mountain goats, but not as extensive. The muskoxen displayed ulcerative lesions on the legs. The caribou had two ulcerative lesions on the upper lip, as well as lesions on the distal part of the legs, around the main and dew claws. A large hairless spherical mass, with the characteristics of a fibroma, was sampled from a Sitka black-tailed deer, which did not show proliferative lesions typical of an ORFV infection. Polymerase chain reaction analyses for B2L, GIF, vIL-10 and ATI demonstrated ORFV specific DNA in all cases. Sequences from Dall's sheep formed a separate cluster, comparable to ORFV from domestic sheep. Sequences from the other species were different from the Dall's sheep sequences, but almost identical to each other. CONCLUSIONS: This is the first major investigation of parapoxvirus infections in large Alaskan game species, and the first report of parapoxvirus infection in caribou and Sitka black-tailed deer. This study shows that most of the wild ruminant species in Alaska and from most parts of Alaska, can carry and be affected by ORFV. These findings call for attention to transmission of ORFV from wildlife to livestock and to hunters, subsistence harvesters, and wildlife biologists.


Asunto(s)
Ectima Contagioso/patología , Ectima Contagioso/virología , Virus del Orf/genética , Rumiantes/virología , Animales , ADN Viral/genética , Ciervos/virología , Reno/virología , Ovinos , Enfermedades de las Ovejas/patología , Enfermedades de las Ovejas/virología
13.
Front Microbiol ; 7: 292, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27014215

RESUMEN

Evidence for bovine viral diarrhea virus (BVDV) infection was detected in 2009-2010 while investigating a pneumonia die-off in Rocky Mountain bighorn sheep (Ovis canadensis, canadensis), and sympatric mountain goats (Oreamnos americanum) in adjacent mountain ranges in Elko County, Nevada. Seroprevalence to BVDV-1 was 81% (N = 32) in the bighorns and 100% (N = 3) in the mountain goats. Serosurveillance from 2011 to 2015 of surviving bighorns and mountain goats as well as sympatric mule deer (Odocoileus hemionus), indicated a prevalence of 72% (N = 45), 45% (N = 51), and 51% (N = 342) respectively. All species had antibody titers to BVDV1 and BVDV2. BVDV1 was isolated in cell culture from three bighorn sheep and a mountain goat kid. BVDV2 was isolated from two mule deer. Six deer (N = 96) sampled in 2013 were positive for BVDV by antigen-capture ELISA on a single ear notch. Wild ungulates and cattle concurrently graze public and private lands in these two mountain ranges, thus providing potential for interspecies viral transmission. Like cattle, mule deer, mountain goats, and bighorn sheep can be infected with BVDV and can develop clinical disease including immunosuppression. Winter migration patterns that increase densities and species interaction during the first and second trimester of gestation may contribute to the long term maintenance of the virus in these wild ungulates. More studies are needed to determine the population level impacts of BVDV infection on these three species.

14.
Syst Appl Microbiol ; 36(8): 533-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24016869

RESUMEN

Five Mycoplasma strains from wild Caprinae were analyzed: four from Alpine ibex (Capra ibex) which died at the Berlin Zoo between 1993 and 1994, one from a Rocky Mountain goat collected in the USA prior to 1987. These five strains represented a population different from the populations belonging to the 'Mycoplasma mycoides cluster' as tested using multi locus sequence typing, Matrix-assisted laser desorption/ionization time of flight mass spectrometry analysis and DNA-DNA hybridization. Analysis of the 16S rRNA gene (rrs), genomic sequence based in silico as well as laboratory DNA-DNA hybridization, and the analysis of phenotypic traits in particular their exceptionally rapid growth all confirmed that they do not belong to any Mycoplasma species described to date. We therefore suggest these strains represent a novel species, for which we propose the name Mycoplasma feriruminatoris sp. nov. The type strain is G5847(T) (=DSM 26019(T)=NCTC 13622(T)) [corrected].


Asunto(s)
Cabras/microbiología , Mycoplasma/clasificación , Mycoplasma/aislamiento & purificación , Animales , Animales Salvajes , Composición de Base , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Genoma Bacteriano , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Mycoplasma/química , Mycoplasma/genética , Mycoplasma/crecimiento & desarrollo , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
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