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Mountain lions (Puma concolor) have historically experienced large‐scale range contractions, but are beginning to recolonize portions of their former range. To reach potential suitable habitats in eastern North America, mountain lions need to move across the grassland and agriculture‐dominated habitats of the Great Plains, which are different from the forested areas associated with mountain lions in western North America. To inform restoration planning in this area, it is important to understand differences in mountain lion habitat selection in this “nontraditional” grassland habitat. We tracked GPS‐collared mountain lions in the Northern Great Plains of Montana and identified movement states (localized or exploratory) using behavioral change point analysis and net‐squared displacement. We compared habitat selection between the different states using step‐selection functions that included several environmental covariates. Similar to elsewhere throughout their range, across both movement states, mountain lions tended to select forested environments that were farther from human development. In contrast to more traditionally occupied mountainous regions, mountain lions in the Great Plains selected areas of lower elevations. They selected areas both near and far from water, but avoided riparian areas and selected more rugged environments when in exploratory movement states. This suggests that mountain lions in the Northern Great Plains are utilizing river corridors, particularly those with rough or broken topography during exploratory phases. To enhance future recolonization and connectivity of mountain lions to the east of our study area, we encourage managers to maintain and restore forest fragments along river corridors in the Great Plains.  相似文献   

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The activity patterns of springhares Pedetes capensis ( Rodentia: Pedetidae ) from the Eastern Cape Province, South Africa, were investigated by counting the number of springhares active above ground at regular intervals throughout the night at different times of the year and under different weather conditions and phases of the moon. A combination of time of year, time of night and level of illumination best explained springhare activity, accounting for 43% of the variation in springhare numbers. Springhare activity generally reached its peak soon after dark, thereafter remaining fairly constant throughout most of the night and only decreasing in the 2–4-h period before sunrise. On those nights when the moon either rose or set during the night, this pattern was modified by the level of illumination. Springhares responded to moonlight by reducing above-ground activity, shifting activity to dark, moonless periods of the night, and by reducing their use of open space. Except for extremes, other weather conditions had no significant effect on springhare activity.  相似文献   

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Many species of vertebrates require multiple habitats to obtain different resources at different stages of their life-cycles. Use of habitat mosaics takes place on a variety of spatial and temporal scales, from a daily requirement for adjacent habitats to seasonal use of geographically separated environments. Mosaics of habitats are also required in some species to allow ontogenetic habitat shifts, while in others each sex may have specific requirements that are met by different habitats. The extent and nature of animal movements are key (but generally poorly known) factors affecting the vulnerability of species to landscape change. The requirement by many species for multiple habitats suggests that their conservation will be most effective in a mosaic environment and that protection of certain high profile habitats alone, such as rainforest, will be insufficient to achieve conservation goals. Management regimes that result in homogenization of habitats should be avoided. Priority should be given to research that identifies the extent to which species can locate habitat mosaics, at different spatial scales and arrangements, in modified environments.  相似文献   

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  1. Globally, large terrestrial carnivores (Carnivora) have suffered precipitous declines in population and range. Today, they must persist in increasingly isolated natural habitat patches within a human-dominated matrix. Effective conservation aimed at supporting carnivores in such landscapes requires species-specific understanding of habitat requirements.
  2. We present results from a review of the published literature to assess the current state of knowledge regarding habitat preferences of the African lion Panthera leo, with the aim of identifying common drivers of habitat use across contexts.
  3. Using the Web of Science, we identified 154 usable articles and extracted information relating to study topic, location, habitats described, land-use type, and any documented habitat preferences.
  4. Only 31 studies documented evidence of habitat use, and collectively, they suggested that preferences for specific habitat types were varied and context-specific. The importance of prey abundance and proximity to water was highlighted in multiple studies. Anthropogenic factors interfered with expected patterns of habitat use. There was evident bias in study locations: 83% of the habitat-use studies were based in only three countries, and 70% were focussed on protected or managed areas.
  5. Our synthesis suggests that lions demonstrate behavioural plasticity in habitat use in response to anthropogenic pressures. To understand the limits of this plasticity and to manage Africa’s changing landscapes effectively for roaming lions, future research should be focussed on analysis of habitat use outside protected areas, taking into account gradients of distance to water, prey abundance, and anthropogenic risk.
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This article describes the hunting tactics and prey selection of the Valley Bisa, a matrilineal, subsistence-oriented society in the Luangwa Valley of Zambia. Although Valley Bisa hunters explain their behavior in their own idioms, many of their tactics, including the stimuli for and timing of hunts, the circular morphology of their hunting patterns, and randomized searches, appear functionally related to the behavior and ecology of their prey. The effects of outlawing traditional harvest techniques and the imposition and enforcement of external constraints on Valley Bisa hunting patterns are discussed. Data on habitats, density of cover, wind direction, species, and initial distance to prey from 50 hunts, in which 16 mammals were killed, are compared and related to success and failure of stalking attempts. Graphs, comparing the numbers of observations for each of four variables with the frequency of stalking attempts, illustrate the cultural style of predation for this group of hunters.This article was initially presented as part of my contribution to a graduate seminar, Public Management of the African Environment, African Studies Program, Indiana University, October 9, 1975. I wish to thank Professor J. Gus Liebenow for extending the invitation to participate in this program.  相似文献   

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Although anthropogenic change is often gradual, the impacts on animal populations may be precipitous if physiological processes create tipping points between energy gain, reproduction or survival. We use 25 years of behavioural, diet and demographic data from elephant seals to characterise their relationships with lifetime fitness. Survival and reproduction increased with mass gain during long foraging trips preceding the pupping seasons, and there was a threshold where individuals that gained an additional 4.8% of their body mass (26 kg, from 206 to 232 kg) increased lifetime reproductive success three-fold (from 1.8 to 4.9 pups). This was due to a two-fold increase in pupping probability (30% to 76%) and a 7% increase in reproductive lifespan (6.0 to 6.4 years). The sharp threshold between mass gain and reproduction may explain reproductive failure observed in many species and demonstrates how small, gradual reductions in prey from anthropogenic disturbance could have profound implications for animal populations.  相似文献   

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The activity patterns and habitat selection of tench in a shallow eutrophic lake were determined by radio telemetry. Environmental variables, including prey availability, depth and vegetational composition were quantified in order to explain observed patterns of distribution. Tench were generally only active at night, foraging on benthic animal prey, particularly chironomid larvae. Feeding fish clearly selected for particular locations although only weak associations with depth and densities of preferred prey were found. In addition, it appears that fish spent a considerable time searching for prey and travelling relatively large distances in the process, with the result that only relatively few prey were ingested during the course of a night. During daylight, fish were almost completely inactive, resting together in favoured locations and displaying a strong association for the littoral emergent vascular plant, Typha angustifolia . This may be because Typha usually grows in relatively deep water and forms stands of relatively widely spaced stems, thus allowing such large fish to penetrate deeply into cover. Management of eutrophic waters to encourage tench should take this habitat preference into account.  相似文献   

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The 5th Symposium on Frugivores and Seed Dispersal, held in Montpellier (France), 13-18 June 2010, brought together more than 220 researchers exemplifying a wide diversity of approaches to the study of frugivory and dispersal of seeds. Following Ted Fleming and Alejandro Estrada's initiative in 1985, this event was a celebration of the 25th anniversary of the first meeting in Veracruz, Mexico. Frugivory and seed dispersal are active research areas that have diversified in multiple directions since 1985 to include evolution (e.g. phylogenetic diversity and dispersal adaptations), physiology (e.g. sensory cues and digestion), landscape ecology (movement patterns), molecular ecology (e.g. gene flow, genetic diversity and structure), community ecology (e.g. mutualistic interaction networks) and conservation biology (effects of hunting, fragmentation, invasion and extinction), among others. This meeting provided an opportunity to assess conceptual and methodological progress, to present ever more sophisticated insights into frugivory in animals and dispersal patterns in plants, and to report the advances made in examining the mechanisms and consequences of seed dispersal for plants and frugivores.  相似文献   

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Predator avoidance is likely to play a strong role in structuringspecies communities, even where actual mortality due to predationis low. In such systems, mortality may be low because predatoravoidance is effective, and if the threat of predation is liftedthen entire community structures may be altered. Where competitionis intense, then competitor avoidance may have a similar impacton communities. Avoidance behaviors have been documented fora wide range of species, but this is the first attempt to documentavoidance behavior within a large carnivore community. Audioplayback techniques are used to examine the risk perceivedby cheetahs from their two main competitors that are also theirmain predators, lions and hyenas. The results from these experimentsshow that cheetahs actively moved away from lion and hyenaplayback experiments, compared with dummy playbacks where no sound was played. Cheetahs showed no differences in their responsesto playbacks dependent on their sex or reproductive status,suggesting they were responding principally to a competitionrather than a predation threat. However, cheetahs were muchless likely to hunt after competitor playbacks than after dummyplaybacks, and this resulted in a lower kill rate after competitorplaybacks, demonstrating that the perceived presence of competitors had a noticeable impact on the foraging rate of cheetahs. Furthermore,while cheetahs moved just as far following lion playbacks asafter hyena playbacks, they spent significantly more time lookingat the loudspeaker and were less likely to make a kill afterlion playbacks, suggesting that cheetahs perceive lions tobe a greater threat than hyenas.  相似文献   

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Age at first reproduction is an important determinant of individual variation in reproductive success in ungulates, but few studies have examined its relationship with later fitness‐related traits in males. We used a long‐term individual based study of a harvested moose population to quantify the individual reproductive performance and survival of males, as well as to examine the determinants of age at first reproduction and consequences of age at first reproduction on lifetime breeding success. The probability that a male successfully reproduced at the age of two was negatively related to the mean age of adult males in the population, but the relationship weakened with increasing population size. Large antlers and large body mass relative to other males in the population increased the number of calves sired at their first successful mating season. In addition, those that successfully reproduced as two year‐olds were more likely to sire calves the next year, making them more productive at a given age compared to those that first reproduced at the age of three or older. We emphasize the importance for males to start reproducing as soon as possible in a harvested population to gain lifetime fitness benefits, as surviving the hunt is a major determinant of reproductive success in this population. We found no costs of early reproduction in males, hence leading to high individual heterogeneity in male reproductive performance. The apparent lack of reproductive costs could partly be explained by the age distribution in the population, individual variation in early‐life body mass and antler size, and differences in probabilities of being hunted of successful and unsuccessful males.  相似文献   

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Researchers have documented hunting by wild chimpanzees (Pan troglodytes) for >30 yr. However, no one had reported the behavior in captive chimpanzees. The Primate Foundation of Arizona (PFA) is a biomedical research facility, and though every effort is made to ensure that rodents and other indigenous animals do not enter cages, an occasional small mammal or bird enters the outside cage area. We document 18 known successful hunts over 2.5 yr by ≥8 captive chimpanzees housed at PFA. The most common prey were rock squirrels (Cittallus variegatus; n = 8) and birds (n = 7). The most common killing method was a bite to the head (n = 9), indicating that the deaths were deliberate and not accidental. Two adult males, 1 wild- and 1 captive-born, together accounted for 11 of the 18 hunting episodes. The chimpanzees generally captured and killed the prey in their outdoor enclosures. The results have implications for the surveillance of outdoor areas in other facilities and the potential for disease or introduction of parasitic vectors, and are also an interesting comparison to wild chimpanzee behavior.  相似文献   

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Striped marlin Kajikia audax are globally Near Threatened and their stock in the Indian Ocean was last assessed as “overfished and subject to overfishing”. Significant gaps in our understanding of their ecology remain, hampering the efforts of fisheries managers to ensure stock sustainability. There is a particular lack of fisheries-independent data. Here we present the results from the first large-scale satellite tracking study of K. audax in the Indian Ocean. We tagged 49 K. audax with pop-up archival satellite-linked tags off the Kenyan coast from 2015 to 2019. Individuals were highly mobile, covering horizontal distances of up to 9187 km over periods ranging up to 183 days, with a mean daily distance of ~48 km. Long-distance movements were recorded to the east and north of East Africa, with the most distant tracks extending north to the Arabian Sea and east to near the Maldives. None of the K. audax swam south of East Africa. Kernel utilization distributions of fish locations demonstrated their shifting seasonal activity hotspots. Over the sport-fishing season (and tagging period) in Kenya, from December to March, K. audax typically stayed off the East African coast. After March, the activity hotspot shifted north to a region close to the Horn of Africa and Socotra Island. Remotely sensed sea surface temperature and chlorophyll-a maps indicated that this seasonal movement could be driven by a shift in prey availability. Our results show the high mobility of K. audax in the Western Indian Ocean, and that individuals seasonally range between two major fishing areas.  相似文献   

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Observations on egg batch production by known female Stegastes partitus and the fates of those egg batches within the nests of known males revealed that spawning success was not a reliable predictor of hatching success and, hence, reproductive success because of high egg batch mortality. Moreover, while numbers of eggs per batch increased with increasing female length, both inter- and intra-individual variation in batch size was considerable, demonstrating that spawning events cannot be considered equivalent. These two findings indicate that spawning success cannot be assumed to provide a direct quantitative substitute for a measure of reproductive success in this benthic spawning reef fish.  相似文献   

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Hunting by Bubi villages around Moka, Bioko, and their impact on the local prey fauna was studied during July–August, 1992. Questionnaires were sent to 45 known hunters in the region in order to find out their techniques and hunting procedures. Hunting trips were also followed (a total of 204 km covered) and counts of animals brought to the villages from 103 recorded trips were also made. There were two main hunting methods employed: trapping and shooting. Most commonly used was snare trapping. At least five different types were used during the study. Guns were less commonly employed. Both techniques are efficient and productive but prey caught by each method differed. Most animals caught by snares were large rodents (Atherurus africanus, Cricetomys emini) and small antelopes (Cephalophus monticola) whereas those shot were usually antelopes (C. monticola and C. ogilbyi), monkeys (Cercopithecus spp.) and, when accompanied by dogs, drills (Mandrillus leucophaeus). The effects of hunting in the region is acute especially since they incur upon the proclaimed protected areas in the south of the island. Hunting trips are gradually being lengthened and areas which were originally unaffected by this activity are now part of the villages' hunting zones.  相似文献   

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1. The objective of the work reported here was to test the hypothesis that in insects that invest considerable energy in sexual displays and courtship, foraging successfully for food affects their subsequent performance and copulatory success in leks. Accordingly, the interactions between body size and diet on initiation of lekking behaviour and copulatory success in male Mediterranean fruit flies Ceratitis capitata (Diptera: Tephritidae) were investigated. 2. Protein‐fed males were heavier and contained more protein and less lipid reserves than protein‐deprived males. Protein‐fed males were more likely to emit pheromone in leks and, consequently, were more likely to copulate than protein‐deprived males. Furthermore, protein‐fed males tended to start calling earlier than their nutritionally deprived competitors. 3. Though size was not related to initiation of lek behaviour, large males were more likely to copulate than small males. Among protein‐fed males, large individuals tended to mate earlier than smaller individuals. 4. Generally, in lek mating systems where a considerable investment of time and energy is required by males, foraging successfully for nutritional resources prior to engaging in territorial or courtship behaviour is essential for reproductive success.  相似文献   

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Abstract.  Mediterranean fruit flies ( Ceratitis capitata Wiedemann, Diptera: Tephritidae) harbor a community of diazotrophic bacteria in their digestive system. The present study aims to test the hypothesis that bacteria contribute to fly fitness by enhancing copulatory success and egg production in males and females, respectively. After eclosion, flies were fed a full diet containing peptides, sugar and minerals, or a sugar diet, lacking peptides. Subgroups from each diet were fed a mixture of the antibiotics ciprofloxacin and piperacillin. The presence of bacteria, food consumption, weight gain, lipid and protein levels, oviposition in females and copulatory success of males were quantified in the four groups. The antibiotic treatment effectively cleared the gut of bacteria. The relative amounts of food consumed (with or without antibiotics) are similar in all groups. The antibiotics do not inhibit feeding, and their ingestion does not affect dry weight or the amount of protein stored, yet females feeding on the full diet without antibiotics have increased lipid levels. Females fed the full diet produce significantly more eggs than females on the sugar diet, but the presence of bacteria does not affect numbers of eggs produced. However, in the absence of bacteria, the oviposition rate of nutritionally stressed females is significantly accelerated. The presence of bacteria in sugar fed males does not provide them with a mating advantage. Conversely, in males fed a full diet, the presence of bacteria is associated significantly with a shorter latency to mate. It is concluded that, because the bacterial community is present at all stages of the fly's life cycle, at least some species are effectively transmitted from parents to offspring, and removal of bacteria affects measurable physiological and behavioural parameters related to fitness, the association between bacteria and the medfly is mutualistic.  相似文献   

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