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1.
The residence time is the amount of time spent within a predefined circle surrounding each point along the movement path of an animal, reflecting its response to resource availability/quality. Two main residence time‐based methods exist in the literature: (1) The variance of residence times along the path plotted against the radius of the circle was suggested to indicate the scale at which the animal perceives its resources; and (2) segments of the path with homogeneous residence times were suggested to indicate distinct behavioral modes, at a certain scale. Here, we modify and integrate these two methods to one framework with two steps of analysis: (1) identifying several distinct, nested scales of area‐restricted search (ARS), providing an indication of how animals view complex resource landscapes, and also the resolutions at which the analysis should proceed; and (2) identifying places which the animal revisits multiple times and performs ARS; for these, we extract two scale‐dependent statistical measures—the mean visit duration and the number of revisits in each place. The association between these measures is suggested as a signature of how animals utilize different habitats or resource types. The framework is validated through computer simulations combining different movement strategies and resource maps. We suggest that the framework provides information that is especially relevant when interpreting movement data in light of optimal behavior models, and which would have remained uncovered by either coarser or finer analyses. 相似文献
2.
Mark A. Ditmer John R. Fieberg Ron A. Moen Steve K. Windels Seth P. Stapleton Tara R. Harris 《Ecology and evolution》2018,8(17):9017-9033
Predators directly impact prey populations through lethal encounters, but understanding nonlethal, indirect effects is also critical because foraging animals often face trade‐offs between predator avoidance and energy intake. Quantifying these indirect effects can be difficult even when it is possible to monitor individuals that regularly interact. Our goal was to understand how movement and resource selection of a predator (wolves; Canis lupus) influence the movement behavior of a prey species (moose; Alces alces). We tested whether moose avoided areas with high predicted wolf resource use in two study areas with differing prey compositions, whether avoidance patterns varied seasonally, and whether daily activity budgets of moose and wolves aligned temporally. We deployed GPS collars on both species at two sites in northern Minnesota. We created seasonal resource selection functions (RSF) for wolves and modeled the relationship between moose first‐passage time (FPT), a method that discerns alterations in movement rates, and wolf RSF values. Larger FPT values suggest rest/foraging, whereas shorter FPT values indicate travel/fleeing. We found that the movements of moose and wolves peaked at similar times of day in both study areas. Moose FPTs were 45% lower in areas most selected for by wolves relative to those avoided. The relationship between wolf RSF and moose FPT was nonlinear and varied seasonally. Differences in FPT between low and high RSF values were greatest in winter (?82.1%) and spring (?57.6%) in northeastern Minnesota and similar for all seasons in the Voyageurs National Park ecosystem. In northeastern Minnesota, where moose comprise a larger percentage of wolf diet, the relationship between moose FPT and wolf RSF was more pronounced (ave. across seasons: ?60.1%) than the Voyageurs National Park ecosystem (?30.4%). These findings highlight the role wolves can play in determining moose behavior, whereby moose spend less time in areas with higher predicted likelihood of wolf resource selection. 相似文献
3.
Sarah C. Webster James C. Beasley Joseph W. Hinton Michael J. Chamberlain 《Ecology and evolution》2022,12(3)
Coyotes (Canis latrans) are a highly adaptable canid species whose behavioral plasticity has allowed them to persist in a wide array of habitats throughout North America. As generalists, coyotes can alter movement patterns and change territorial strategies between residency (high site fidelity) and transiency (low site fidelity) to maximize fitness. Uncertainty remains about resident and transient coyote movement patterns and habitat use because research has reached conflicting conclusions regarding patterns of habitat use by both groups. We quantified effects of habitat on resident and transient coyote movement behavior using first passage time (FPT) analysis, which assesses recursive movement along an individual''s movement path to delineate where they exhibit area‐restricted search (ARS) behaviors relative to habitat attributes. We quantified monthly movement rates for 171 coyotes (76 residents and 53 transients) and then used estimated FPT values in generalized linear mixed models to quantify monthly habitat use for resident and transient coyotes. Transients had greater movement rates than residents across all months except January. Resident FPT values were positively correlated with agricultural land cover during fall and winter, but negatively correlated with agriculture during spring. Resident FPT values were also negatively correlated with developed habitats during May–August, deciduous land cover during June–August, and wetlands during September–January except November. FPT values of transient coyotes were positively correlated with developed areas throughout much of the year and near wetlands during July–September. Transient FPT values were negatively correlated with agriculture during all months except June and July. High FPT values (ARS behavior) of residents and transients were generally correlated with greater densities of edge habitat. Although we observed high individual variation in space use, our study found substantive differences in habitat use between residents and transients, providing further evidence that complexity and plasticity of coyote habitat use is influenced by territorial strategy. 相似文献
4.
Theresa Spatz;Jakob Katzenberger;Nicolas Friess;Christian Gelpke;Eckhard Gottschalk;Martin Hormann;Steffen Koschkar;Thomas Pfeiffer;Stefan Stübing;Christoph Sudfeldt;Sascha Rösner;Dana G. Schabo;Nina Farwig; 《Journal of avian biology》2022,2022(10):e02925
Intrinsic and extrinsic drivers shape the space use of wide-ranging raptors. A large proportion of raptors are migrants that shift their activity ranges between summer and winter habitats, where they encounter different environmental conditions. Analysing the effects of intrinsic and extrinsic drivers on the space use in summer and winter habitats provides crucial insights into the ecology of migratory raptors. Here, we investigated the seasonal space use by 43 red kites Milvus milvus tracked by GPS-transmitters across central and south-western Europe over seven consecutive years. We compared space use patterns, i.e. activity range sizes and mean daily distances of the birds between summer and winter, and analysed the influence of extrinsic (landscape diversity, primary productivity) and intrinsic factors (sex). Within summer, we investigated the influence of breeding success and sex on activity range sizes. We further analysed differences in habitat availability and habitat selection between seasons. We found that space use was smaller in summers than in winters. When compared to those of males, activity ranges of female red kites were larger in summers and smaller in winters, with shorter mean daily distances in both seasons. Within summer, successfully breeding red kites had smaller activity range sizes in both sexes, but this effect was stronger in females than in males. Regardless of the season, landscape diversity was positively correlated with space use, whereas primary productivity was negatively correlated with it. The habitat use differed between seasons, with agricultural landscapes being less proportionally used in summers than in winters. Overall, we showed that both intrinsic and extrinsic drivers shaped space use in both seasons, leading to differences in space use patterns and habitat use in migratory raptors between their summer and winter habitats. Our findings underline the importance of consideration of the entire annual cycle of migratory species for conservation management. 相似文献
5.
L. D. EINODER B. PAGE S. D. GOLDSWORTHY S. C. DE LITTLE C. J. A. BRADSHAW 《Austral ecology》2011,36(4):461-475
Identifying the primary foraging grounds of abundant top predators is of importance in marine management to identify areas of high biological significance, and to assess the extent of competition with fisheries. We studied the search effort and habitat selection of the highly abundant short‐tailed shearwater Puffinus tenuirostris to assess the search strategies employed by this wide‐ranging seabird. During the chick‐rearing period 52 individuals were tracked performing 39 short foraging trips (1–2 days), and 13 long trips (11–32 days). First‐passage time analysis revealed that 46% of birds performing short trips employed area‐restricted searches, concentrating search effort at an average scale of 14 ± 5 km. Foraging searches were more continuous for the other 54%, who travelled faster to cover greater distances, with little evidence of area‐restricted searches. The prey returned indicated that continuous searchers consumed similar prey mass, but greater prey diversity than area‐restricted search birds. On long trips 23% of birds travelled 500–1000 km to neritic (continental shelf) habitats, showing weak evidence of preference for areas of higher chlorophyll a concentration, and foraged at a similar spatial scale to short trips. The other 76% performed rapid outbound flights of 1000–3600 km across oceanic habitats commuting to regions with higher chlorophyll a. The spatial scale of search effort in oceanic habitat varied widely with some performing broad‐scale searches (260–560 km) followed by finer‐scale nested searches (16–170 km). This study demonstrates that a range of search strategies are employed when exploiting prey across ocean basins. The trade‐offs between different search strategies are discussed to identify the value of these contrasting behaviours to wide‐ranging seabirds. 相似文献
6.
The elongate, functionally limbless flap-footed lizards(family Pygopodidae) are found throughout Australia, ranging into southern New Guinea. Despite their diversity and abundance in most Australian ecosystems, pygopodids have attracted little scientific study. An intensive ecological study of one pygopodid, Burton's legless lizard(Lialis burtonis Gray 1835), was conducted in Australia's tropical Northern Territory. L. burtonis eats nothing but other lizards, primarily skinks, and appears to feed relatively infrequently(only 20.8% of stomachs contained prey). Ovulation and mating occur chiefly in the late dry-season(beginning around September), and most egg-laying takes place in the early to middle wet-season(November–January). Females can lay multiple clutches per year, some of which may be fertilised with stored sperm. Free-ranging L. burtonis are sedentary ambush foragers, with radio-tracked lizards moving on average 5 m/day. Most foraging is done diurnally, but lizards may be active at any time of day or night. Radiotracked lizards were usually found in leaf-litter microhabitats, a preference that was also evident in habitat-choice experiments using field enclosures. Lizards typically buried themselves in 6–8 cm of litter; at this depth, they detect potential prey items while staying hidden from predators and prey and avoiding lethally high temperatures. 相似文献
7.
Ryan R. Germain Richard Schuster Corey E. Tarwater Wesley M. Hochachka Peter Arcese 《Ibis》2018,160(3):568-581
Individual animal fitness can be strongly influenced by the ability to recognize habitat features which may be beneficial. Many studies focus on the effects of habitat on annual reproductive rate, even though adult survival is typically a greater influence on fitness and population growth in vertebrate species with intermediate to long lifespans. Understanding the effects of preferred habitat on individuals over the annual cycle is therefore necessary to predict its influences on individual fitness. This is particularly true in species that are resident and territorial year‐round in the temperate zone, which may face potential trade‐offs between habitat that maximizes reproduction and that which maximizes non‐breeding season (‘over‐winter’) survival. We used a 37‐year study of Song Sparrows Melospiza melodia residing territorially year‐round on a small island to examine what habitat features influenced adult over‐winter survival, how site‐specific variation in adult survival vs. annual reproductive rate influenced long‐term habitat preference, and if preferred sites on average conferred higher individual fitness. Habitat features such as area of shrub cover and exposure to intertidal coastline predicted adult over‐winter survival independent of individual age or sex, population size, or winter weather. Long‐term habitat preference (measured as occupation rate) was better predicted by site‐specific annual reproductive rate than by expected over‐winter survival, but preferred sites maximized fitness on average over the entire annual cycle,. Although adult over‐winter survival had a greater influence on population growth (λ) than did reproductive rate, the influence of reproductive rate on λ increased in preferred sites because site‐specific variation in reproductive rate was higher than variation in expected over‐winter survival. Because preferred habitats tended to have higher mean site‐specific reproductive and adult survival rates, territorial birds in this population do not appear to experience seasonal trade‐offs in preferred habitat but are predicted to incur substantial fitness costs of settling in less‐preferred sites. 相似文献
8.
By studying the responses of different species to urbanization, it is possible to understand the impact of this type of habitat modification and to explore, more generally, the link between variations in the environment and changes in behaviour. We radio collared 17 badgers Meles meles from six social groups in a 1 km2 urban study area in Brighton, UK, where local badger population density was high, and collected data on their ranging behaviour between 2005 and 2007. We aimed to determine how badgers adapt their behaviour to an urban environment and to assess the generality of previously reported differences in the ranging and territorial behaviour of urban and rural badgers. Analysis of habitat preferences and movement patterns suggested that garden habitat was principally used for foraging, while scrub and allotment habitats were important in allowing animals to travel from one part of their range to another. Group and individual home ranges were the smallest so far recorded for badgers (mean 100% minimum convex polygons=9.26 and 4.91 ha, respectively). Individual range size was negatively correlated with the availability of garden habitat, suggesting that the rich food resources provided by gardens enabled ranges to be small. Group ranges were mostly non-contiguous and there was no evidence of territorial scent marking; rather, activity was mainly restricted to areas in the vicinity of main setts. It is clear that badgers can adapt successfully to urban habitats and that this process affects various aspects of their behaviour. However, our high-density population of urban badgers displayed patterns of behaviour that differed not only from those of typical rural badgers, but also in some respects from those of a previously studied low-density urban population. We conclude that generalizations about the effects of urbanization must be made with caution. 相似文献
9.
First Passage Time Analysis of Animal Movement and Insights into the Functional Response 总被引:2,自引:0,他引:2
Movement plays a role in structuring the interactions between individuals, their environment, and other species. Although
movement models coupled with empirical data are widely used to study animal distribution, they have seldom been used to study
search time. This paper proposes first passage time as a novel approach for understanding the effect of the landscape on animal
movement and search time. In the context of animal movement, first passage time is the time taken for an animal to reach a
specified site for the first time. We synthesize current first passage time theory and derive a general first passage time
equation for animal movement. This equation is related to the Fokker–Planck equation, which is used to describe the distribution
of animals in the landscape. We illustrate the first passage time method by analyzing the effect of territorial behavior on
the time required for a red fox to locate prey throughout its home range. Using first passage time to compute search times,
we consider the effect of two different searching modes on a functional response. We show that random searching leads to a
Holling type III functional response. First passage time analysis provides a new tool for studying how animal movement may
influence ecological processes. 相似文献
10.
Ashley Bennison Thomas W. Bodey Stephen C. Votier W. James Grecian Ewan D. Wakefield Mark Jessopp 《Ecology and evolution》2018,8(1):13-24
Search behavior is often used as a proxy for foraging effort within studies of animal movement, despite it being only one part of the foraging process, which also includes prey capture. While methods for validating prey capture exist, many studies rely solely on behavioral annotation of animal movement data to identify search and infer prey capture attempts. However, the degree to which search correlates with prey capture is largely untested. This study applied seven behavioral annotation methods to identify search behavior from GPS tracks of northern gannets (Morus bassanus), and compared outputs to the occurrence of dives recorded by simultaneously deployed time–depth recorders. We tested how behavioral annotation methods vary in their ability to identify search behavior leading to dive events. There was considerable variation in the number of dives occurring within search areas across methods. Hidden Markov models proved to be the most successful, with 81% of all dives occurring within areas identified as search. k‐Means clustering and first passage time had the highest rates of dives occurring outside identified search behavior. First passage time and hidden Markov models had the lowest rates of false positives, identifying fewer search areas with no dives. All behavioral annotation methods had advantages and drawbacks in terms of the complexity of analysis and ability to reflect prey capture events while minimizing the number of false positives and false negatives. We used these results, with consideration of analytical difficulty, to provide advice on the most appropriate methods for use where prey capture behavior is not available. This study highlights a need to critically assess and carefully choose a behavioral annotation method suitable for the research question being addressed, or resulting species management frameworks established. 相似文献
11.
Predicting population extinction risk is a fundamental application of ecological theory to the practice of conservation biology. Here, we compared the prediction performance of a wide array of stochastic, population dynamics models against direct observations of the extinction process from an extensive experimental data set. By varying a series of biological and statistical assumptions in the proposed models, we were able to identify the assumptions that affected predictions about population extinction. We also show how certain autocorrelation structures can emerge due to interspecific interactions, and that accounting for the stochastic effect of these interactions can improve predictions of the extinction process. We conclude that it is possible to account for the stochastic effects of community interactions on extinction when using single‐species time series. 相似文献
12.
Effects of anthropogenic activities on habitats and species communities and populations are complex and vary across species depending on their ecological traits. Movement ecology may provide important insights into species’ responses to habitat structures and quality. We investigated how movement behavior across a human‐modified landscape depends on species identity and species traits, with particular focus on habitat specialization, feeding guilds, and dispersal behavior. We tracked 34 individuals of nine Afrotropical bird species during three years in an anthropogenic riparian landscape of East Africa. We investigated whether species’ functional traits predicted their habitat use and movement behavior better than species’ identities. Our results indicate that habitat specialists mainly occur in dense riparian thickets, while habitat generalists do occur in agricultural land. Home‐ranges of omnivorous habitat generalists are larger than of frugivorous and insectivorous generalists and omnivorous and insectivorous specialists. Movement speed was highest in settlement areas for all species, with activity peaks during morning and afternoon for habitat specialists. Our results reveal that functional traits and species identity provide complementary insights into responses of organisms to habitat structures and habitat quality. 相似文献
13.
14.
城市生境质量对生物多样性保护有至关重要的作用,以北京市为例分析2000—2015年北京市不同土地利用类型的空间分布特征和不同区域之间的差异,并借助In VEST-Habitat Quality模型评估了北京市4个时期(2000年、2005年、2010年和2015年)、4个区域(首都功能核心区、城市发展新区、城市功能拓展区、生态涵养发展区)的生境退化程度和生境质量变化情况。结果表明:(1)从2000年到2015年,建设用地增加了近40%,耕地、湿地是其快速扩张的主要来源,城市发展新区的建设用地增加了60%;(2)主要的生态用地(林地、草地、湿地)所占比例总体增加了5.71%,但是总体景观结构异质性减弱,斑块破碎化程度加大;(3)生境质量总体下降了2%,表现出明显的区域差异,首都功能核心区和生态涵养发展区的生境质量总值逐渐升高;生境退化度逐渐增加,最严重的区域在城市功能拓展区以及平原-山区交界地带。对区域生态服务价值评估的有益探索,为今后进一步城市景观格局的构建和优化提供依据和参考。 相似文献
15.
16.
A wide variety of nano-biotechnological applications are being developed for nanoparticles based on in vitro diagnostic and imaging systems. Some of these systems allow highly sensitive detection of molecular biomarkers. Frequently, the very low concentration of the biomarkers makes very difficult the mathematical simulation of the motion of nanoparticles based on classical, partial differential equations. We address the issue of incubation times for low concentration systems using Monte Carlo simulations. We describe a mathematical model and computer simulation of Brownian motion of nanoparticle–bioprobe–polymer contrast agent complexes and their hybridisation to immobilised targets. We present results for the dependence of incubation times on the number of particles available for detection, and the geometric layout of the DNA-detection assay on the chip. 相似文献
17.
H. Herrmann 《Biometrical journal. Biometrische Zeitschrift》1979,21(7):629-643
Starting with the classical occupancy with boxes, balls and probabilities for occupying boxes, we employ new models: a ball, which met a box, occupies this box with a probability depending on the size of box content, and - using several kinds of balls - by the composition of the content too. For that purpose several models are constructed with distinctive forms of the conditions. Dealing with these models - they are special MARKO vian chains - we pay attention mainly to the so called first passage time Tz for defined events Z; in particular for certain events Z we have to prove that Tz is a random variable, and have to set up the appropriate probability generating function. 相似文献
18.
M. J. Robertson† K. D. Clarke‡ D. A. Scruton‡ J. A. Brown§ 《Journal of fish biology》2003,63(5):1208-1218
Radio‐telemetry was used to investigate movement of large, mainly mature male (80%) Atlantic salmon Salmo salar parr in Stoney River, Newfoundland during early winter (November; water temperature 6·0 ± 0·1° C) and mid‐winter (January to February; 0·8 ± 0·0° C). Site fidelity of parr in early winter was low. Parr moved between fluvial and lacustrine habitats and were active throughout the diel cycle. Parr caught in fluvial habitats in mid‐winter were smaller and younger than parr caught in early winter. Site fidelity of parr in mid‐winter was greater than in early winter. Parr in mid‐winter moved between fluvial and adjacent small lacustrine habitats, but avoided a larger pond inhabited by large piscivorous fishes. Instream movement rates in mid‐winter were lower than in early winter and occurred primarily during hours of darkness (dawn, dusk and night). Fluvial habitats were relatively stable and ice‐free throughout the study periods. These results suggested that large Atlantic salmon parr utilize a variety of habitats and remain active throughout the winter, even under stable environmental conditions. 相似文献
19.
The influence of small-scale variation in habitat on winter trout distribution and diet in an afforested catchment 总被引:1,自引:0,他引:1
(1) Habitat influences on trout distribution and diet at a reach scale were analysed over a single winter in a conifer-afforested catchment in Ireland, in an area subject to very low levels of atmospheric pollution. (2) A total of 234 salmonids were sampled from which 1194 individual prey items were recovered. Salmonids were sampled at eleven sites over a 2 km stretch of the river Douglas, a third order stream of the river Araglin in the Munster Blackwater, Co. Cork, Ireland. (3) In this winter study, water depth and flow primarily influenced trout distribution. (4) Stepwise multiple regression was used to identify the most influential environmental factors on trout metrics. Trout biomass was positively correlated to maximum depth and the percentage of pool area within sites, but density and condition were not significantly influenced by habitat variation at the reach scale. (5) The results from diet analysis suggest that trout are heterogeneous generalist feeders in winter, preying mainly on Trichoptera and Ephemeroptera species. Prey diversity in the diet of individuals throughout the study was positively correlated to the percentage of deciduous vegetation, undercut banks and coniferous vegetation, whilst the prey sub-population diversity at site scale was not related to any of the habitat variables measured. 相似文献
20.
Xu Jiliang Zhang Xiaohui Zhang Zhengwang Zheng Guangmei Ruan Xiangfeng Zhang Keyin Xi Bo 《Frontiers of Biology in China》2006,1(2):174-181
Home range and habitat use of male Reeves’s pheasant (Syrmaticus reevesii) were studied during winter of 2001∼2002 and 2002∼2003 in the Dongzhai National Nature Reserve, Henan Province. Results from
five individuals of Reeves’s pheasant with over 30 relocations, indicated that the average size of home range was 10.03 ±
1.17 hm2 by Minimum Convex Polygon method, 8.60 ± 0.35 hm2 by 90% Harmonic Mean Transformation method, and 9.50 ± 1.90 hm2 by 95% Fixed Kernel method. It was observed that the winter range is smaller than that in the breeding season. The mean core
area of the home range was found to be 1.88 ± 0.37 hm2. Although the habitat composition of the core area varied greatly for individuals, a large part of the habitats used were
composed of confier and broadleaf mixed forests, masson pine forests, fir forests, and shrubs. Habitat use within the study
area was non-random, while habitats within home ranges were randomly used. Habitat use was dictated by tree diameter at breast
height, shrub height and coverage at 2.0 m. The proximity between forests and shrubs were also found to be important in providing
refuge for the birds during winter. Recommendations for conservation management include protecting the existing habitats in
Dongzhai National Nature Reserve, increasing suitable habitat for Reeves’s Pheasant through artificial plantations (e.g. firs),
and restoring some parts of the large shrub area into forests.
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Translated from Biodiversity Science, 2005, 13 (5) [译自: 生物多样性, 2005,13(5)] 相似文献