Article
Ecology
Andrew S. Jones, Esther S. Rubin, Matthew J. Clement, Larisa E. Harding, Jacob I. Mesler
Summary: This study investigated how mountain lions impact habitat selection and mortality risk of bighorn sheep. The findings suggest that bighorn sheep select habitats based on ruggedness and slope, reducing the risk of mountain lion predation. Additionally, increasing group size decreases the risk of mortality.
JOURNAL OF WILDLIFE MANAGEMENT
(2022)
Article
Ecology
Marcus E. E. Blum, Kelley M. M. Stewart, Mike Cox, Kevin T. T. Shoemaker, Joe R. R. Bennett, Benjamin W. W. Sullivan, Brian F. F. Wakeling, Vernon C. C. Bleich
Summary: Selection of forage and habitats in bighorn sheep is influenced by the nutritional needs of individuals, with some females sacrificing nutritional quality for the safety of their offspring. Our study examined diet quality and composition before and after parturition, revealing a tradeoff between diet quality and provisioning status. The results provide insight into habitat selection and evolutionary processes in these specialized artiodactyls.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2023)
Article
Ecology
Kelly M. Proffitt, Alyson B. Courtemanch, Sarah R. Dewey, Blake Lowrey, Douglas E. Mcwhirter, Kevin L. Monteith, J. Terrill Paterson, Jay Rotella, Patrick J. White, Robert A. Garrott
Summary: Research on spatial and temporal variations in survival and pregnancy rates of bighorn sheep in the Rocky Mountains indicates that summer growing conditions play a crucial role in the probability of pregnancy and winter survival. The study provides insights into the factors influencing vital rates and emphasizes the importance of managing nutritional resources on bighorn sheep habitats to enhance overall population condition.
Article
Ecology
B. Lowrey, J. D. DeVoe, K. M. Proffitt, R. A. Garrott
Summary: Successful restoration programs have enabled formerly declining ungulate species in North America to be broadly distributed across their native ranges. Habitat models inform translocation decisions, with resident and migrant populations showing differing selection patterns. Specific predictions of bighorn sheep habitat in western Montana were made for potential translocations, with behavior-specific approaches showing differences in seasonal selection patterns between migrants and residents.
Article
Ecology
Shannon C. Forshee, Michael S. Mitchell, Thomas R. Stephenson
Summary: In order to improve lifetime reproductive success, maternal ungulates should adopt behavioral strategies to reduce the risk of offspring mortality. This study examined the habitat selection of Sierra Nevada bighorn sheep to understand how maternal individuals minimize predation risk and to quantify the availability of neonatal habitat. The results showed that females selected habitat with low probability of encountering mountain lions and near escape terrain, and their choice of vegetation type depended on the risk of encountering mountain lions. The study also found differences in the prevalence and connectivity of highly selected lambing habitat across subpopulations, which may explain variations in lamb recruitment and adequacy of lambing habitat among subpopulations.
JOURNAL OF WILDLIFE MANAGEMENT
(2022)
Article
Ecology
Aidan Brushett, Jesse Whittington, Bryan Macbeth, John M. Fryxell
Summary: Understanding the behavioral changes induced by ungulate parturition is important for effective population management, but identifying birth sites and dates is challenging. This study used movement data from GPS collared bighorn sheep to identify lambing events and investigate resource selection and responses to human use. Results showed that postpartum ewes preferentially selected high-elevation, sunny, rugged, and remote sites. It is recommended that managers minimize human disturbance in lambing areas and ensure access to suitable habitat during the periparturient period.
Article
Zoology
Ty J. Werdel, Jonathan A. Jenks, John T. Kanta, Chadwick P. Lehman, Teresa J. Frink
Summary: The study monitored the translocated bighorn sheep in the Black Hills region and found that they underwent an acclimation period after release, with their home range gradually shrinking and travel distances decreasing.
Article
Ecology
Manuel Vargas-Felipe, Luis Pellegrin, Aldo A. Guevara-Carrizales, A. Pastor Lopez-Monroy, Hugo Jair Escalante, Jose A. Gonzalez-Fraga
Summary: Monitoring wildlife using camera traps is crucial for conservation efforts, but manual image classification remains expensive. This paper presents an automatic methodology for labeling images captured by camera traps, focusing on the analysis of the desert bighorn sheep. The method achieved high classification performances and the collected data set and models are publicly available to support further research on this species.
ECOLOGICAL INFORMATICS
(2021)
Article
Veterinary Sciences
Amelie Mathieu, Caeley Thacker, Irene Teske, Emily Jenkins, Brent Wagner, Bryan Macbeth, Stephen Raverty, Margo Pybus
Summary: This study identified cases of mortality in the Radium-Stoddart bighorn sheep population in southeastern British Columbia, Canada, caused by infection with the giant liver fluke, Fascioloides magna. The affected animals exhibited typical clinical signs and pathology consistent with previous reports on other hosts. The change in migratory behavior among some rams may have contributed to their exposure to F. magna. This research highlights the pathogenic nature of the giant liver fluke and its threat to the conservation of bighorn sheep herds in endemic regions.
JOURNAL OF WILDLIFE DISEASES
(2022)
Article
Ecology
Danielle M. Glass, Paige R. Prentice, Ashley D. Evans, Oswald J. Schmitz
Summary: This study analyzes the surface water use and movement patterns of desert bighorn sheep populations in the Mojave Desert. The results suggest that temperature is the most significant factor influencing the sheep's visitation to water sources. Furthermore, individual animals exhibit changes in movement patterns when accessing surface water. The study also emphasizes the importance for managers to monitor water sources when the maximum daily temperature exceeds 35 degrees Celsius.
JOURNAL OF WILDLIFE MANAGEMENT
(2022)
Article
Ecology
Elizabeth Flesch, Tabitha Graves, Jennifer Thomson, Kelly Proffitt, Robert Garrott
Summary: Understanding the influence of population attributes on genetic diversity is important for biological conservation. This study on bighorn sheep populations found that connectivity between populations, human-assisted gene flow, and minimum count were correlated with average pairwise kinship, while population origin was less important.
Article
Biochemistry & Molecular Biology
Sarah H. D. Santos, Rhiannon M. Peery, Joshua M. Miller, Anh Dao, Feng-Hua Lyu, Xin Li, Meng-Hua Li, David W. Coltman
Summary: Whole-genome sequencing has helped advance the study of species evolution, particularly in detecting genealogical discordant events like ancient hybridization and incomplete lineage sorting. The study on bighorn and thinhorn sheep revealed patterns of introgression and discordance, with Stone sheep potentially originating from multiple ancient periods of secondary contact with bighorn sheep.
Article
Ecology
John Draper, Torrey Rodgers, Julie K. Young
Summary: This study quantifies habitat selection and evaluates diet of bobcats in the Sonoran Desert using multiple sampling techniques. Findings show that bobcats have smaller home ranges during the hot season and primarily consume smaller prey. The study highlights the benefits of employing multiple sampling methods to understand the ecology of elusive species.
BMC ECOLOGY AND EVOLUTION
(2022)
Article
Multidisciplinary Sciences
Aziz Subach, Arik Dorfman, Bar Avidov, Adi Domer, Yehonatan Samocha, Inon Scharf
Summary: This study investigated the behavior and ecology of the desert horned viper in the northwestern Negev desert, Israel. The vipers were found to move slower in vegetation-dense microhabitats compared to open dune areas. Their movement in open areas was likely influenced by the availability of prey. The vipers were more active early in the season, with peak activity right after sunset and a smaller peak at sunrise, possibly indicating a search for burrows to spend the day. Inter-sexual and between-year differences were also observed, such as variations in size and population size. The information provided in this study can contribute to the conservation of this viper species, as sand dunes are threatened habitats in Israel.
ROYAL SOCIETY OPEN SCIENCE
(2022)
Article
Multidisciplinary Sciences
Grace E. Enns, Bill Jex, Mark S. Boyce
Summary: We studied the seasonal space-use and migration patterns of Stone's sheep in the Cassiar Mountains of northern British Columbia. The study aimed to determine the timing of migrations, characterize ranges and routes, document altitudinal changes, and assess individual migration strategies. The findings provide important information for land-use planning and preservation of Stone's sheep migrations.
Article
Ecology
Jason P. Marshal
AFRICAN JOURNAL OF ECOLOGY
(2017)
Article
Ecology
Jason P. Marshal, Christopher Rankin, H. P. Nel, Francesca Parrini
EUROPEAN JOURNAL OF WILDLIFE RESEARCH
(2016)
Article
Ecology
James W. Cain, Jay V. Gedir, Jason P. Marshal, Paul R. Krausman, Jamison D. Allen, Glenn C. Duff, Brian D. Jansen, John R. Morgart
Article
Zoology
Robynne Kotze, Mark Keith, Christiaan W. Winterbach, Hanlie E. K. Winterbach, Jason P. Marshal
JOURNAL OF MAMMALOGY
(2018)
Article
Ecology
Francesca Parrini, Giacomo D'Ammando, Jason P. Marshal
AFRICAN JOURNAL OF ECOLOGY
(2019)
Article
Ecology
Cornelius J. Louw, Jason P. Marshal, Hercules P. Nel, Paul J. Funston
AFRICAN JOURNAL OF WILDLIFE RESEARCH
(2019)
Article
Biodiversity Conservation
Zaara Kidwai, Jose Jimenez, Cornelius J. Louw, H. P. Nel, Jason P. Marshal
GLOBAL ECOLOGY AND CONSERVATION
(2019)
Article
Ecology
Elena Mariotti, Francesca Parrini, Cornelius J. Louw, Jason P. Marshal
AFRICAN JOURNAL OF WILDLIFE RESEARCH
(2020)
Article
Ecology
Elena Mariotti, Francesca Parrini, Cornelius J. Louw, Jason P. Marshal
AFRICAN JOURNAL OF RANGE & FORAGE SCIENCE
(2020)
Article
Ecology
Jason P. Marshal, Giacomo D'ammando, Francesca Parrini
AFRICAN JOURNAL OF WILDLIFE RESEARCH
(2020)
Article
Ecology
Robynne Kotze, Jason P. Marshal, Christiaan W. Winterbach, Hanlie E. K. Winterbach, Mark Keith
Summary: Habitat loss can lead to increased intraspecific competition, which decreases cub survival and proportion recorded in the population for African lions. This effect is exacerbated by prey abundance and pride size, highlighting the complex interactions between habitat loss, crowding, and demographic consequences on large carnivore populations.
AFRICAN JOURNAL OF ECOLOGY
(2021)
Article
Ecology
Alexandra M. Evans, Jason P. Marshal, Graham J. Alexander
Summary: This study investigated the effects of vegetation structure and anthropogenic development on reptile occurrence in a Malagasy dry forest during the dry season. The results showed that most reptile species and those most sensitive to habitat transformation were associated with intact forest edges with denser green vegetation, which should be the focus of conservation efforts in tropical dry forests. The study also emphasized the importance of setting and scale in interpreting habitat-use patterns, as well as the value of local, species-specific studies.
Article
Zoology
Jeannine McManus, Jason P. Marshal, Mark Keith, Thulani Tshabalala, Bool Smuts, Adrian Treves, Rafael Reyna
Summary: Human-transformed landscapes leave patches of natural habitat for wildlife, and the survival of species depends on their ability to adapt to new habitats and secure resources and reproductive opportunities in altered environments. Leopards in South Africa are crucial for conservation planning due to their high trophic status and wide-ranging movements. Factors like spatial scale, sex-related differences, and conspecific location play important roles in habitat selection for solitary felids.
JOURNAL OF MAMMALOGY
(2021)
Article
Ecology
Jason P. Marshal, Thulani Tshabalala, Francesca Parrini
Summary: The study on individual responses of nyala antelopes to vegetation greenness revealed a relationship between home-range greenness and strength of selection, which varied with season and canopy structure. The findings suggest that a spatial resource gradient on a landscape may serve as a valuable model for foraging animals to adapt to changes in resources.
AFRICAN JOURNAL OF WILDLIFE RESEARCH
(2021)
Article
Zoology
Cornelius J. Louw, Sam M. Ferreira, Jason P. Marshal
Summary: Predator avoidance strategies vary across ungulate species, with some selecting predator-free zones and others spending less time near surface water. The scarcity of predator-free zones in confined spaces may increase predation risk for species with low surface water requirements.
Article
Ecology
Narendra Nelli, Diana Francis, Ricardo Fonseca, Olivier Masson, Mamadou Sow, Emmanuel Bosc
Summary: This study investigates the changes in the atmospheric electric field (Ez) during foggy conditions in the hyperarid region of the United Arab Emirates. The results show that as fog persists, Ez becomes more variable due to the absorption and redistribution of charges by the fog, which alters the ion balance and affects electrical conductivity in the atmosphere.
JOURNAL OF ARID ENVIRONMENTS
(2024)
Article
Ecology
Ezra Hadad, Amir Balaban, Jakub Z. Kosicki, Reuven Yosef
Summary: This study investigated whether the prey of striped hyenas has adapted to the change in the natural environment caused by human activities, particularly artificial light at night (ALAN). The results showed that ALAN had no impact on the diet or den distribution of the hyenas in central Israel. The study also found that domestic animals were the most common prey, and there were also some vegetative species in their diet. Overall, the feeding behavior of striped hyenas is influenced by geographical region, habitat, and human activities.
JOURNAL OF ARID ENVIRONMENTS
(2024)
Article
Ecology
Rahim Najafi Tireh Shabankareh, Pardis Ziaee, Mohammad Javad Abedini
Summary: This study evaluated the IMERG satellite-based precipitation product in the Fars province of Iran using daily rain gauges as reference data. The results showed that the product tends to overestimate light rainfall and underestimate heavy rainfall, with the best performance in the 40-80 mm/day range. The accuracy of the product varies by month and is less biased in months with milder temperatures. Additionally, there was a higher correlation in mid-elevated areas, positive bias in low-elevated areas, and negative bias in high-elevated areas. Longer time scales showed considerable improvement in the IMERG estimates.
JOURNAL OF ARID ENVIRONMENTS
(2024)
