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1.
Conservation of rare populations requires managing habitat throughout the year, especially during winter when northern populations may be limited by food and predation. Consequently, we examined distribution of nonbreeding western snowy plovers (Charadrius alexandrinus), including individually marked birds that were year-round residents and others that were migrants, in coastal northern California. Over 2 years, banded plovers exhibited high site faithfulness, occupying small linear stretches of beach (752 ± 626 m). Sites occupied by plovers had more brown algae (e.g., Macrocystis, Nereocystis, Postelsia, and Fucus) and associated invertebrates (e.g., amphipods, and flies), were wider, and had less vegetation than unoccupied sites. Our findings suggest that wintering plovers select habitats with more food and where they could more easily detect predators. Maintaining habitat with attributes that support abundant food (i.e., brown algae) and reduce predation risk (i.e., wide beaches, limited obstructive cover) may be important to individual survival and maintaining the Pacific Coast population of snowy plovers. Protecting occupied sites from human disturbance, which adversely alters nonbreeding habitat (i.e., beach grooming) and directly causes mortality, may be essential for conserving the Pacific coast population of the snowy plover, and it may benefit other shorebirds. © 2011 The Wildlife Society. 相似文献
2.
Low hatching success may limit progress towards reaching productivity goals for Atlantic Coast piping plover (Charadrius melodus) recovery, despite management strategies to protect eggs from predators and decrease human disturbance of birds on nests. We measured piping plover hatching success on Eastern Long Island beaches and identified the major causes of egg failure to better understand why eggs that were otherwise intact (not depredated or destroyed by tidal flooding) failed to hatch. We documented egg and nest fates, dissected contents of unhatched eggs to determine viability, and recorded human and predator activity near a subset of plover nests on Suffolk County Parks properties. The low hatching success we recorded (0.60) in 2006 and 2007 would require higher chick survival rates than are typically observed for piping plovers to meet recovery targets for productivity. Few eggs showed signs of poor viability and overall egg hatchability was comparable to other ground nesting birds. Most egg failure was due to either depredation at unexclosed nests or nest abandonment by adults. The best predictor of nest abandonment was the maximum number of red fox tracks (Vulpes vulpes) counted on nearby transects (β = −1.16, 95% CI: −2.0 to −0.3) and we found evidence that plovers abandoned eggs in response to predation risk (e.g., a fox circling a nest exclosure). Adults from abandoned nests may have deserted eggs or been depredated. In either case, intact and viable eggs were abandoned. Nest abandonment was not related to human activity near nests, which were buffered from human disturbance by symbolic string fencing. Our results suggest that depredation and nest abandonment (e.g., desertion or death of adults) due to predator disturbance, not human disturbance or poor egg viability, contributed to the low hatching success we recorded. Active predator removal in addition to modification of predator exclosure use and design may be necessary to prevent direct (egg depredation) and indirect (nest abandonment) negative effects of predators on hatching success. © 2010 The Wildlife Society. 相似文献
3.
Olivia M. Smith William E. Snyder Jeb P. Owen 《Biological reviews of the Cambridge Philosophical Society》2020,95(3):652-679
Enteric illnesses remain the second largest source of communicable diseases worldwide, and wild birds are suspected sources for human infection. This has led to efforts to reduce pathogen spillover through deterrence of wildlife and removal of wildlife habitat, particularly within farming systems, which can compromise conservation efforts and the ecosystem services wild birds provide. Further, Salmonella spp. are a significant cause of avian mortality, leading to additional conservation concerns. Despite numerous studies of enteric bacteria in wild birds and policies to discourage birds from food systems, we lack a comprehensive understanding of wild bird involvement in transmission of enteric bacteria to humans. Here, we propose a framework for understanding spillover of enteric pathogens from wild birds to humans, which includes pathogen acquisition, reservoir competence and bacterial shedding, contact with people and food, and pathogen survival in the environment. We place the literature into this framework to identify important knowledge gaps. Second, we conduct a meta‐analysis of prevalence data for three human enteric pathogens, Campylobacter spp., E. coli, and Salmonella spp., in 431 North American breeding bird species. Our literature review revealed that only 3% of studies addressed the complete system of pathogen transmission. In our meta‐analysis, we found a Campylobacter spp. prevalence of 27% across wild birds, while prevalence estimates of pathogenic E. coli (20%) and Salmonella spp. (6.4%) were lower. There was significant bias in which bird species have been tested, with most studies focusing on a small number of taxa that are common near people (e.g. European starlings Sturnus vulgaris and rock pigeons Columba livia) or commonly in contact with human waste (e.g. gulls). No pathogen prevalence data were available for 65% of North American breeding bird species, including many commonly in contact with humans (e.g. black‐billed magpie Pica hudsonia and great blue heron Ardea herodias), and our metadata suggest that some under‐studied species, taxonomic groups, and guilds may represent equivalent or greater risk to human infection than heavily studied species. We conclude that current data do not provide sufficient information to determine the likelihood of enteric pathogen spillover from wild birds to humans and thus preclude management solutions. The primary focus in the literature on pathogen prevalence likely overestimates the probability of enteric pathogen spillover from wild birds to humans because a pathogen must survive long enough at an infectious dose and be a strain that is able to colonize humans to cause infection. We propose that future research should focus on the large number of under‐studied species commonly in contact with people and food production and demonstrate shedding of bacterial strains pathogenic to humans into the environment where people may contact them. Finally, studies assessing the duration and intensity of bacterial shedding and survival of bacteria in the environment in bird faeces will help provide crucial missing information necessary to calculate spillover probability. Addressing these essential knowledge gaps will support policy to reduce enteric pathogen spillover to humans and enhance bird conservation efforts that are currently undermined by unsupported fears of pathogen spillover from wild birds. 相似文献
4.
Sverine Ligout Marie-France Bouissou Xavier Boivin 《Applied animal behaviour science》2008,113(1-3):175-188
Tactile contact is often used to improve the human–foal relationship, in particular during sensitive periods such as weaning. However, the method used to provide the contact (forced or unforced) may affect subsequent reactions to humans. The aim of our study was to compare the effect of forced and unforced handling at weaning on horses’ behaviour towards humans and handling.A total of 23 Anglo-Arabian foals received individual human contact at weaning. Constrained-handled foals (forced human contact; FC, n = 8) were stroked while being restrained (i.e., held by the halter without being led) so that human contact was forced. Unconstrained-handled foals (unforced human contact; UC, n = 7) were stroked without any restraint and could thus avoid contact if they so wanted. Each individual was handled 5 min twice a day for 14 consecutive days. Control foals were not handled (no contact; NC, n = 8). Foals’ reactions towards a human (e.g. proximity and contact seeking), and their manageability (fitting of a halter) were then assessed. The animals from the different treatments were then mixed and tested again 4 months later. Non-parametric Mann–Whitney U-tests were used to compare experimental groups.Only forced human contact reduced fear reactions toward humans (e.g. shorter latency to approach a passive human, P < 0.01; shorter latency to touch the foal, P < 0.05) in the short-term (immediately after the handling sessions) and increased foals’ manageability in a familiar environment (shorter latency to be placed a halter on and less defences displayed, P < 0.05). It had no effect in an unfamiliar environment. These effects did not last longer than 4 months.Forced human contact thus appears to be more efficient in improving human–horse relationships and subsequent handling than unforced human contact. However, the lack of effect on reactivity towards humans in an unfamiliar environment, and the lack of long-term effects suggest that this method needs to be improved to be more effective. Some of our results suggest that horses could perceive human contact (i.e., stroking) as positive, however further studies are needed to confirm this hypothesis. 相似文献
5.
Maï Yasué 《Journal of Ethology》2005,23(2):199-204
Animals may alter their foraging behaviour in the presence of humans because they perceive humans as potential predators. In this study I determined whether people caused shorebirds to reduce feeding rates at a stopover site in coastal British Columbia, Canada. I controlled for prey density and flock size because these variables may influence both the foraging rates as well as the effect of human disturbance on feeding efficiency. Semipalmated plovers decreased feeding rates when there were more people on the beach (multiple regression: F1,15=5.86, b=0.59, P=0.029, R2=37.6%). For least sandpipers, the effect of human densities on feeding rates depended on flock size (F1,21=5.97, P=0.023) and amphipod availability (F1,21=4.98, P=0.037). This study demonstrated the importance of measuring subtle behavioural changes in foraging rates along with key ecological variables in order to assess the true impact of human disturbance on migratory shorebirds. 相似文献
6.
Harold F. Greeney Robert C. Dobbs Paul R. Martin Rudolphe A. Gelis 《Journal of Field Ornithology》2008,79(2):113-129
ABSTRACT Grallaria and Grallaricula antpittas are poorly known ground antbirds (Formicariidae), which reach their center of diversity in the tropical Andes region. Here we review published literature on the reproductive ecology of these two genera, summarizing and synthesizing the information. Nests have been described for 13 of the 31 species of Grallaria and four of the eight species of Grallaricula. For both genera, nests are open cups placed either against a strong support (e.g., tree trunks; Grallaria) or with multiple small supports (e.g., vine tangles; both genera). Nest lining is generally sparse, with nest cup composition ranging from humid material (e.g., moss) to primarily sticks and leaf material, depending on the species. Grallaria typically lay two bluish‐green to turquoise eggs, sometimes with spotting, whereas Grallaricula lay 1–2 eggs with heavy markings and pale brown or buffy (rarely light green) background coloration. For the few species where information is available, both male and female parents are believed to participate in building, incubation, and nestling provisioning, with high incubation attentiveness (often >90%, especially later in incubation), and incubation periods of 17–21 d (Grallaria) and 15–20 d (Grallaricula). Grallaria nestlings are frequently fed earthworms (Oligochaeta) in addition to a variety of arthropods. Nestlings have pale skin (Grallaria) or dark skin (both genera), with pale or dark down (Grallaria) or red‐brown down (Grallaricula). Nestlings in both genera usually have brilliant orange mouth linings and cloacas, and usually fledge 15–19 d post hatching. Rapid probing, where adults rapidly thrust their bills into the nest and lining, is commonly observed across species during incubation and nestling periods, but its function remains unknown. Overall, our knowledge of the breeding biology of antpittas has improved significantly in recent years. However, much remains to be learned for most species. 相似文献
7.
During incubation, Canada Geese (Branta canadensis) and other waterfowl flush from their nests in response to the approach of potential predators and subsequently return to nests after the threat of predation has abated. Differences among individuals in their responses to such disturbance (e.g., how close a potential predator approaches before flushing) are thought to reflect variation in female age, the reproductive value of clutches, and nest site characteristics. From 26 April to 26 May 2010, we examined the possible effects of these factors on the behavior of female Canada Geese (B. c. interior) on Akimiski Island, Nunavut. We used humans as surrogate predators and flushing distance and return time after disturbance as response variables. The distance at which females flushed in response to approaching humans was best explained by the density of vegetation around nests, with females on better concealed nests flushing at closer distances. We also found a weak relationship between return time and clutch size, with females with larger clutches returning to nests sooner. The frequency of human visits did not affect either female flushing distance or return time. Female Canada Geese in our study appeared to minimize risk of their own injury or death (future reproductive potential) in escape decisions, whereas return times appeared to minimize the risk of nest predation (current reproductive investment). 相似文献
8.
We examined the genetic structure of snowy plovers (Charadrius alexandrinus) in North America, the Caribbean, and the west coast of South America to quantify variation within and among breeding areas
and to test the validity of three previously recognized subspecies. Sequences (676 bp) from domains I and II of the mitochondrial
control region were analyzed for 166 snowy plovers from 20 breeding areas. Variation was also examined at 10 microsatellite
loci for 144 snowy plovers from 14 breeding areas. The mtDNA and microsatellite data provided strong evidence that the Puerto
Rican breeding group is genetically divergent from sites in the continental U.S. (net sequence divergence = 0.38%; F
ST for microsatellites = 0.190). Our data also revealed high levels of differentiation between sites from South America and
North America (net sequence divergence = 0.81%; F
ST for microsatellites = 0.253). In contrast, there was little genetic structure among breeding sites within the continental
U.S. Our results suggest that snowy plovers in Florida should be considered part of C. a. nivosus (rather than part of C. a. tenuirostris, where they are currently placed), whereas snowy plovers from Puerto Rico should be considered part of C. a. tenuirostris. Snowy plovers in South America should remain a separate subspecies (C. a. occidentalis). Although U.S. Pacific and Gulf Coast breeding areas were not genetically distinct from other continental U.S. sites, demographic
isolation, unique coastal habitats, and recent population declines suggest they warrant special concern. 相似文献
9.
During nesting, many temperate and tropical shorebirds are exposed to direct solar radiation and face heat stress. The aim
of our study was to determine whether belly-soaking (wetting of ventral plumage) contributes to reducing excess body heat
in Kentish plovers Charadrius alexandrinus. We captured incubating plovers on sunny days at their exposed nests, and placed them inside cloth bags at ground level in
exposed sites for 5 min. This produced an increase in the ambient temperature experienced by the plovers, as well as an increase
in the body temperature of the plovers. We simulated belly-soaking by submerging the ventral parts in water for about 10 s
immediately after removing the birds from the bag. The body temperature of the plovers was lowered after simulated belly-soaking.
Our results indicate that belly-soaking is a behavioural strategy to quickly reduce body temperature in heat-stressed plovers. 相似文献
10.
Objective: Partitioning of body energy content in the aleptinemic ob/ob mouse differs from that in wild‐type mice, but it is not known whether parallel differences exist between humans with leptin (Lep) gene mutations and healthy adults. The objective of this study was to evaluate body composition in three leptin‐treated Turkish adults homozygous for a missense mutation (C→T substitution at codon 105 resulting in Arg→Trp) of Lep. Research Methods and Procedures: Subjects, one male and two female Turkish family members, were evaluated at baseline and treated for 18 months with r‐MetHuLeptin. Patient data (fat mass, energy content) were compared with adult sex‐specific predicted values (adjusted for weight, height, and age) derived in healthy control subjects. Results: Weight loss with leptin treatment was substantial, ranging from 43.9% to 52.1%. At baseline and with leptin treatment, the two women had a fat mass and energy content similar (±12%) to predicted values. Baseline fat and energy content in the male patient was high compared with predicted values (e.g., fat +33%) but approached and reached normal values (e.g., fat, +2%) after 18 months of leptin therapy. Discussion: Adult women with Lep mutations had body composition similar to normal women at baseline and with leptin treatment. In contrast, the man with a Lep mutation had high body fat in the untreated state but a normal male phenotype with leptin administration, possibly secondary to androgenic fat partitioning effects. Fat and energy partitioning can, thus, be quantitatively assessed and linked with potential hormonal mechanisms in humans with inherited disturbances in energy regulation. 相似文献
11.
W. R. Siegfried 《Ostrich》2013,84(3):173-178
Many small plovers Charadrius spp. have sexually monomorphic plumage and cryptic sexual size dimorphism. The objective of our study was to assess the variation in body sizes between male and female plovers breeding in Madagascar. We collected blood samples and data on adult body sizes of four small plovers (Madagascar Plover Charadrius thoracicus, Kittlitz's Plover C. pecuarius, White-fronted Plover C. marginatus and Three-banded Plover C. tricollaris), and used molecular genetic markers to sex the adults. We found significant differences in body size among the four species, and between sexes. Furthermore, individuals from the southern ecoregion tended to be larger than in the western ecoregion. The Madagascar Plover's body size was significantly more dimorphic than the Kittlitz's and White-fronted Plovers. Breeding Malagasy plovers' show significant sexual size dimorphism (SSD): Madagascar Plover females were heavier and had longer wings than males, whereas the males had longer tarsi; in White-fronted Plover only wing length was different between the sexes. Taken together, our work reports SSD in small African plovers that exhibit monomorphic plumage, and we propose that SSD may be more common than currently acknowledged; we term this 'cryptic sexual size dimorphism'. Our results also suggest sexual selection and/or natural selection exert different pressures on body size in different Malagasy plover species. 相似文献
12.
Mpanya A Hendrickx D Vuna M Kanyinda A Lumbala C Tshilombo V Mitashi P Luboya O Kande V Boelaert M Lefèvre P Lutumba P 《PLoS neglected tropical diseases》2012,6(1):e1467
Background
Control of human African trypanosomiasis (sleeping sickness) in the Democratic Republic of Congo is based on mass population active screening by mobile teams. Although generally considered a successful strategy, the community participation rates in these screening activities and ensuing treatment remain low in the Kasai-Oriental province. A better understanding of the reasons behind this observation is necessary to improve regional control activities.Methods
Thirteen focus group discussions were held in five health zones of the Kasai-Oriental province to gain insights in the regional perceptions regarding sleeping sickness and the national control programme''s activities.Principal Findings
Sleeping sickness is well known among the population and is considered a serious and life-threatening disease. The disease is acknowledged to have severe implications for the individual (e.g., persistence of manic periods and trembling hands, even after treatment), at the family level (e.g., income loss, conflicts, separations) and for communities (e.g., disruption of community life and activities). Several important barriers to screening and treatment were identified. Fear of drug toxicity, lack of confidentiality during screening procedures, financial barriers and a lack of communication between the mobile teams and local communities were described. Additionally, a number of regionally accepted prohibitions related to sleeping sickness treatment were described that were found to be a strong impediment to disease screening and treatment. These prohibitions, which do not seem to have a rational basis, have far-reaching socio-economic repercussions and severely restrict the participation in day-to-day life.Conclusions/Significance
A mobile screening calendar more adapted to the local conditions with more respect for privacy, the use of less toxic drugs, and a better understanding of the origin as well as better communication about the prohibitions related to treatment would facilitate higher participation rates among the Kasai-Oriental population in sleeping sickness screening and treatment activities organized by the national HAT control programme. 相似文献13.
We describe an unknown mode of solar‐assisted egg development in the crab plover Dromas ardeola, a shorebird that breeds in self‐excavated burrows. The insulating properties of the nest burrow and the intense solar radiation allowed egg development at near‐optimal temperature (35.2°C±0.2) and humidity (60.2%±4.4), allowing a very low incubation attendance by the parent birds (28.3% of time, with recesses lasting up to 58 h). Crab plovers did not abandon completely parental incubation, possibly because of the need to turn their egg, and because the slight warming provided by parents (0.8°C) may improve hatching. This is the first case of solar assisted incubation in a species unrelated to the Megapodiidae, the only birds known to develop their eggs without contact incubation. 相似文献
14.
Brief Communication: Quantitative‐ and molecular‐genetic differentiation in humans and chimpanzees: Implications for the evolutionary processes underlying cranial diversification
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Timothy D. Weaver 《American journal of physical anthropology》2014,154(4):615-620
Estimates of the amount of genetic differentiation in humans among major geographic regions (e.g., Eastern Asia vs. Europe) from quantitative‐genetic analyses of cranial measurements closely match those from classical‐ and molecular‐genetic markers. Typically, among‐region differences account for ~10% of the total variation. This correspondence is generally interpreted as evidence for the importance of neutral evolutionary processes (e.g., genetic drift) in generating among‐region differences in human cranial form, but it was initially surprising because human cranial diversity was frequently assumed to show a strong signature of natural selection. Is the human degree of similarity of cranial and DNA‐sequence estimates of among‐region genetic differentiation unusual? How do comparisons with other taxa illuminate the evolutionary processes underlying cranial diversification? Chimpanzees provide a useful starting point for placing the human results in a broader comparative context, because common chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) are the extant species most closely related to humans. To address these questions, I used 27 cranial measurements collected on a sample of 861 humans and 263 chimpanzees to estimate the amount of genetic differentiation between pairs of groups (between regions for humans and between species or subspecies for chimpanzees). Consistent with previous results, the human cranial estimates are quite similar to published DNA‐sequence estimates. In contrast, the chimpanzee cranial estimates are much smaller than published DNA‐sequence estimates. It appears that cranial differentiation has been limited in chimpanzees relative to humans. Am J Phys Anthropol 154:615–620, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
15.
C. albicans is an opportunistic fungus causing life-threatening systemic infections particularly in immunocompromised individuals. The organism is a commensal in humans and grows either aerobically, e.g., the oral cavity, or anaerobically, e.g., the gut. We studied anaerobic growth of C. albicans in a defined yeast nitrogen base dextrose medium after adaptation and subculturing in an anaerobic chamber. At 37°C in suspension culture, much slower growth was observed anaerobically with a generation time of 248 min compared to 98 min for aerobic growth. Although the organism grew well on solid medium, shaking increased the growth rate in suspension culture at 37°C. Growth was enhanced at acidic pH compared to neutral or alkaline pH. Cells grown anaerobically produced hyphae, but did not produce biofilm on plastic surface or denture acrylic under either static conditions or with mild shaking, conditions that support aerobic biofilm formation. 相似文献
16.
Habitat use has important consequences for avian reproductive success and survival. In coastal areas with recreational activity, human disturbance may limit use of otherwise suitable habitat. Snowy plovers Charadrius nivosus have a patchy breeding distribution along the coastal areas on the Florida Panhandle, USA. Our goal was to determine the relative effects of seasonal human disturbance and habitat requirements on snowy plover habitat use. We surveyed 303 sites for snowy plovers, human disturbance, and habitat features between January and July 2009 and 2010. We made multiple visits during three different sampling periods that corresponded to snowy plover breeding: pre‐breeding, incubation, and brood‐rearing and used multi‐season occupancy models to examine whether human disturbance, habitat features, or both influenced site occupancy, colonization (probability of transition from an unoccupied site to an occupied site), and extinction (probability of transition from an occupied site to an unoccupied site). Snowy plover site occupancy and colonization was negatively associated with human disturbance and site extinction was positively associated with human disturbance. Interdune vegetation had a negative effect on occupancy and colonization, indicating that plovers were less likely to use areas with uniform, dense vegetation among dunes. Also, dune shape, beach debris, and access to low‐energy foraging areas influenced site occupancy, colonization, and extinction. Plovers used habitat based on beach characteristics that provided stage‐specific resource needs; however, human disturbance was the strongest predictor of site occupancy. In addition, vegetation plantings used to enhance dune rehabilitation may negatively impact plover site occupancy. Management actions that decrease human disturbance, such as symbolic fencing and signage, may increase the amount of breeding habitat available to snowy plovers on the Florida Panhandle and in other areas with high human activity. The specific areas that require this protection may vary across snowy plover life history stages. 相似文献
17.
Anthony G. Comuzzie Shelley A. Cole Lisa Martin K. Dee Carey Michael C. Mahaney John Blangero John L. VandeBerg 《Obesity (Silver Spring, Md.)》2003,11(1):75-80
Objective: At present, rodents represent the most common animal model for research in obesity and its comorbidities (e.g., type 2 diabetes and coronary heart disease), however, there are several physiological and developmental differences between rodents and humans reflective of their relatively ancient evolutionary divergence (approximately 65 to 75 million years ago). Therefore, we are currently developing the baboon as a nonhuman primate model for the study of the genetics of obesity. Research Methods and Procedures: At present, we are collecting extensive phenotypic data in a large pedigreed colony (N > 2000) of baboons housed at the Southwest Foundation for Biomedical Research in San Antonio, Texas. The long‐term goal of this project is to identify genes influencing adiposity‐related phenotypes and to test hypotheses regarding their pleiotropic effects on other phenotypes related to increased risk for a variety of common diseases (e.g., coronary heart disease and type 2 diabetes). Results: To date we have obtained various adipose‐specific endocrine measures, adipose tissue biopsies, and estimates of body composition on a substantial portion of our pedigreed colony. The pattern of adipose tissue accumulation follows closely that seen in humans, and we have detected significant additive genetic heritabilities for these obesity‐related phenotypes. Discussion: Given the physiological and developmental similarities between humans and baboons, along with the ability to collect data under well‐controlled situations and the extensive pedigree data available in our colony, the baboon offers an extremely valuable nonhuman primate model for the study of obesity and its comorbidities. 相似文献
18.
Jessica L. Braunstein Joseph D. Clark Ryan H. Williamson William H. Stiver 《The Journal of wildlife management》2020,84(6):1038-1050
Conflicts between humans and wildlife have become increasingly important challenges for resource managers along the urban-wildland interface. Food conditioning (i.e., reliance by an animal on anthropogenic foods) of American black bears (Ursus americanus) is related to conflict behavior (i.e., being bold or aggressive toward humans, consuming human food or garbage, causing property damage) and often occurs in communities adjacent to Great Smoky Mountains National Park (GRSM or Park), USA. The goal of our study was to evaluate black bear space use in GRSM and in exurban areas on surrounding private lands and to identify factors associated with food conditioning and conflict behavior. We radio-collared 53 bears (29 males, 24 females) from 2015 to 2017 to compare space use characteristics and used carbon isotopic signatures (δ13C) from bear hair to assess food conditioning. We then performed an integrated step selection function (iSSF) analysis to characterize and compare movement and resource use as related to food conditioning. Based on the stable isotope analyses, 24 bears were classified as food conditioned (FC; 16 males and 8 females) and 37 were not food conditioned (NFC; 14 males and 23 females). Annual 95% kernel density estimate (KDE) home ranges and 50% KDE core area estimates of female and male bears did not differ by level of food conditioning (i.e., mean δ13C), but 95% and 50% home ranges of FC females were smaller than NFC females when data from 2015, a year of food scarcity and abnormally large home ranges, were excluded. The mean proportion of exurban development (e.g., roads, buildings, openings) within 95% KDE and 50% KDE home ranges of females increased with mean δ13C (i.e., greater food conditioning). The iSSF models indicated that FC bears were more likely to use forest openings associated with higher levels of development than NFC bears. We used those models to demonstrate how landscape modifications can reduce bear use of exurban areas, particularly for NFC bears. Our stable isotope, movement, and resource use data indicate that conflict behaviors displayed by many bears within GRSM were learned in areas outside Park boundaries. © 2020 The Wildlife Society. 相似文献
19.
Abby N. Powell Francesca J. Cuthbert Lauren C. Wemmer Alice W. Doolittle Shane T. Feirer 《Zoo biology》1997,16(6):461-477
Techniques for captive-rearing and releasing piping plovers (Charadrius melodus) were developed using a surrogate species, killdeer (Charadrius vociferus). We compared captive- and parent-reared killdeer, and parent-reared piping plovers and determined that growth and behavior were similar. After surrogate trials determined that captive-rearing was feasible, we used the same methods to raise piping plover chicks from salvaged eggs. For captive-reared chick of both species, survival to fledging was higher than and behaviors similar to parent-reared chicks in the wild. Rearing techniques were fine-tuned, and ten piping plover fledglings were released to the wild. Based on our results, we developed recommendations for captive-rearing piping plovers using salvaged eggs to enhance productivity of small populations. Zoo Biol 16:461–477, 1997. © 1997 Wiley-Liss, Inc. 相似文献
20.
Rhiannon P. Jakopak Jessica Western Kevin L. Monteith 《The Journal of wildlife management》2021,85(7):1309-1320
Members of the public play a primary role in successful implementation of wildlife management plans, making communication between scientists and the public a vital component of wildlife management. Although there is substantial public interest in the health of ungulate populations, stakeholder perspectives can vary widely, rendering a single approach to communication ineffective. To improve science communication, we characterized perspectives regarding issues negatively affecting mule deer (Odocoileus hemionus) in Wyoming, USA. We used Q methodology, a mixed quantitative-qualitative approach where participants ranked a series of statements followed by semi-structured interviews, to identify shared perspectives. We interviewed individuals (n = 37) representing prominent stakeholder groups (e.g., ranchers, hunters, conservation non-profits) in Wyoming. We identified 3 perspectives (52% of variance explained) that captured shared views regarding what factors are negatively affecting mule deer: bottom-up (n = 17 participants; 26% variance), human contributions (n = 9; 14% variance), and top-down (n = 8; 12% variance) perspectives. Most participants shared the idea that mule deer are being negatively affected, but participants diverged in views as to the primary issues. Perspectives ranged from being focused on bottom-up factors (e.g., habitat fragmentation, condition of winter ranges) to top-down factors (e.g., predation, disease) to factors focused on human contributions (e.g., human activity, public and political interests). Based on how participants diverged in perspectives and their interest in mule deer management, we discuss opportunities for scientists to improve communication by incorporating ecological complexity and nuance, moving towards a 2-way dialogue of communication, and sharing their own first-hand experiences in future communications with stakeholders. © 2021 The Authors. The Journal of Wildlife Management published by Wiley Periodicals LLC on behalf of The Wildlife Society. 相似文献