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991.
992.
Winnie Eckardt Tara S. Stoinski Stacy Rosenbaum Rachel Santymire 《Ecology and evolution》2019,9(9):5248-5259
Living in a rapidly changing environment can alter stress physiology at the population level, with negative impacts on health, reproductive rates, and mortality that may ultimately result in species decline. Small, isolated animal populations where genetic diversity is low are at particular risks, such as endangered Virunga mountain gorillas (Gorilla beringei beringei). Along with climate change‐associated environmental shifts that are affecting the entire population, subpopulations of the Virunga gorillas have recently experienced extreme changes in their social environment. As the growing population moves closer to the forest's carrying capacity, the gorillas are coping with rising population density, increased frequencies of interactions between social units, and changing habitat use (e.g., more overlapping home ranges and routine ranging at higher elevations). Using noninvasive monitoring of fecal glucocorticoid metabolites (FGM) on 115 habituated Virunga gorillas, we investigated how social and ecological variation are related to baseline FGM levels, to better understand the adaptive capacity of mountain gorillas and monitor potential physiological indicators of population decline risks. Generalized linear mixed models revealed elevated mean monthly baseline FGM levels in months with higher rainfall and higher mean maximum and minimum temperature, suggesting that Virunga gorillas might be sensitive to predicted warming and rainfall trends involving longer, warmer dry seasons and more concentrated and extreme rainfall occurrences. Exclusive use of smaller home range areas was linked to elevated baseline FGM levels, which may reflect reduced feeding efficiency and increased travel efforts to actively avoid neighboring groups. The potential for additive effects of stress‐inducing factors could have short‐ and long‐term impacts on the reproduction, health, and ultimately survival of the Virunga gorilla population. The ongoing effects of environmental changes and population dynamics must be closely monitored and used to develop effective long‐term conservation strategies that can help address these risk factors. 相似文献
993.
994.
Cluster Computing - Cognitive Radio Network is an emerging popular wireless network, designed for efficient spectrum utilization. It enables unlicensed users to access the unused portion of the... 相似文献
995.
Biological Invasions - Introduced Phragmites (Phragmites australis ssp. australis) forms part of an invasion assemblage in North America that includes non-native insect herbivores and parasitoids,... 相似文献
996.
BioControl - Supplemental food application to crops as a resource for generalist predators has shown utility for promoting their establishment and persistence leading to enhanced biological control... 相似文献
997.
Amy E. Mayer Thomas J. McGreevy Jr Charles Brown Laken S. Ganoe Brian D. Gerber 《Population Ecology》2022,64(4):323-335
Human developments have detrimental effects on wildlife populations globally with carnivores being particularly sensitive. The bobcat (Lynx rufus) is often considered an adaptable mesocarnivore that occurs throughout varied landcover types within its wide distribution and may be less susceptible to the negative effects of development. Our objectives were to investigate the landscape occupancy dynamics of bobcats in a highly developed and densely populated region of the northeastern United States to evaluate the sensitivity of bobcat occurrence to natural and anthropogenic landscape features. We established a large-scale camera trapping survey throughout Rhode Island, USA, sampling from 2018 to 2020. Using dynamic occupancy models, we found initial site occupancy was positively influenced by the amount of forested wetland habitat, while increasing road density and shrub cover negatively influenced the probability of site colonization. Surprisingly, we found no hypothesized variables to influence site-level extirpation probability, or any seasonal effects on dynamic parameters. Lastly, we found that forest cover and road density negatively influenced the probability of detection. The probability of occupancy was high, >0.8, throughout much of the study area (49%), but we also found relatively high site transients, with the probability a site would change occurrence status from season to season at ≈0.27 in the majority of the study area (70%). Our results show that although bobcats can persist in human-dominated landscapes, they require contiguous natural areas to do so. Future expansion of road infrastructure may reduce habitat connectivity and increase road mortalities, thus jeopardizing the population. 相似文献
998.
In Vitro Cellular & Developmental Biology - Plant - Anaphyllum wightii Schott. is an ethnomedicinally significant plant endemic to the southern region of Western Ghats. The present study aimed... 相似文献
999.
Gritsyshin V. A. Artyushin I. V. Burskaya V. O. Sheftel B. I. Lebedev V. S. Bannikova A. A. 《Biology Bulletin》2022,49(1):1-13
Biology Bulletin - We studied the polymorphism of the cytb gene in two forms of the Lesser White-toothed Shrew species complex: Crocidura suaveolens s. stricto and C. sibirica. The haplotypes of C.... 相似文献
1000.
Biology Bulletin - The features of the structural adaptive changes in the somatic muscles of rainbow trout are presented at various stages of early post-hatching ontogenesis. The development of the... 相似文献