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Although residential areas are often unfavourable for wildlife, some species can take advantage of the available shelter and anthropogenic sources of food such as supplementary feeding. The European hedgehog (Erinaceus europaeus) is increasingly associated with gardens and villages and less so with arable farmland. Suggested drivers for this include the following: hedgehogs’ attraction to higher food densities, including natural prey and anthropogenic sources, a greater range of day nest sites and warmer microclimates in rural villages, coupled with decreased risk of predation by badgers (Meles meles). We investigated the contribution of these drivers by radio-tracking hedgehogs on four arable sites, two with badgers present. Seventy-eight hedgehogs were tracked, 32 yielding enough data to calculate home range sizes. At the home range and landscape scales, gardens and buildings were the highest ranked habitats compared with their availability. Woodland and arable land were the lowest ranked compared with their availability. Villages were the most selected habitat for nesting. When hedgehogs were found closer to buildings, their ranges were smaller and we speculate this is due to increased food availability in villages. Where badgers were present hedgehogs remained closer to cover and their home ranges were on average 12.2 ha smaller. On badger-occupied sites, 50% fewer radio-tracking fixes were on arable land. We conclude that resource availability coupled with nest site selection and badger presence drives hedgehogs’ selection of rural villages. We found no effect of ambient temperature on habitat use. We recommend focusing conservation efforts on maintaining hedgehog populations in rural villages.  相似文献   

3.
Effects of habitat loss and fragmentation on the behavior of individual organisms may have direct consequences on population viability in altered forest ecosystems. The American marten (Martes americana) is a forest specialist considered as one of the most sensitive species to human-induced disturbances. As some studies have shown that martens cannot tolerate >30–40% clear-cuts within their home range, we investigated marten space use (home range size and overlap) and habitat selection in landscapes fragmented by 2 different patterns of timber harvesting in the black spruce boreal forest: dispersed-cut landscapes (10–80 ha cut-blocks) and clustered-cut landscapes (50–200 ha cut-blocks). We installed radio-collars on female martens and determined 20 winter home ranges (100% minimum convex polygons and 60–90% kernels) in dispersed-cut (n = 8) and clustered-cut (n = 12) landscapes. Home range size was not related to the proportion of clear-cuts (i.e., habitat loss), but rather to the proportion of mixedwood stands 70–120 years old. However, female body condition was correlated to habitat condition inside their home ranges (i.e., amount of residual forest and recent clear-cuts). At the home range scale, we determined that mixedwood forests were also among the most used forest stands and the least used were recent clear-cuts and forested bogs, using resource selection functions. At the landscape scale, home ranges included more mixedwood forests than random polygons and marten high activity zones were composed of more residual forest and less human-induced disturbances (clear-cuts, edges, and roads). These results suggest that mixedwood forests, which occupy approximately 10% of the study area, play a critical role for martens in this conifer-dominated boreal landscape. We recommend permanent retention or special management considerations for these isolated stands, as harvesting mixedwood often leads to forest composition conversion that would reduce the availability of this highly used habitat. © The Wildlife Society, 2013  相似文献   

4.
《Mammalian Biology》2014,79(1):71-76
We analyzed the habitat use of stone martens and red foxes based on incidental observations within the urbanized zone of Wrocław, SW Poland. We compared proportional habitat use at observation sites with randomly selected points and evaluated differences in distance to the water sources and to urban boundaries. Habitat use by both species was different from what we had expected from random points. Stone martens used high-density housing more frequently than red foxes and that expected from random points and avoided open and industrial areas, whereas red foxes used housing estates significantly more often than expected and avoided high-density housing. Both species used the other habitats according to their availability. Stone martens often selected habitats located closer to the city centre, whereas red foxes often selected habitats closer to urban borders than expected. The distribution of red foxes and stone martens is influenced by several factors including the availability of shelter and food, as well as the opportunity to move around undetected. Interspecific competition may also play an important role in habitat selection. Stone martens seem to be better adapted to urbanized areas than red foxes.  相似文献   

5.
Eurasian pine martens are considered habitat specialists, associated primarily with mature stands of mesic mixed wood forest habitats, and avoid areas without overhead cover The species is found throughout the temperate and boreal regions of the continent but on the Mediterranean island of Minorca, introduced pine martens thrive in a competitor- and predator-free environment I test the prediction that because of evolved prey-capture and predator avoidance strategies Minorcan martens should select habitats most similar to temperate and northern parts of their range Scat index routes were used to quantify pine marten habitat selection Marten did not demonstrate any habitat type preferences although observed use of pine forests and coastal shrublands was slighly greater than expected Marten were indifferent to overhead cover whereas mesic sites and areas of tall high shrub density were favored Small mammal trap indices and preferred prey suggested that martens commonly used non-forested areas My results demonstrated that on Minorca pine martens were habitat generalists In the absence of predators open non-forested habitats were equally important to pine marten as were forested ones  相似文献   

6.
Studies at small spatial scale are often fundamental to highlight the behavioural plasticity of a species and thus have important implications for conservation planning, in particular for species usually considered as habitat specialists. We investigated second-order habitat selection of the European pine marten in an area dominated by deciduous oak forest and open fields in central Italy, by radio-tracking 16 pine martens (eight males, eight females). Pine martens placed home ranges in areas with more open field than in the study area, whereas woodland (oak and conifer forests) comprised a smaller portion of the home range than predominant forest character of the studied area. Although the presence of the species in the open habitats has been documented, to our knowledge, our results provide the first evidence of home range establishment in this cover type by pine marten at population level. The combination of low predation risk and high availability of resources could allow pine martens to occupy open fields in our study area. We highlighted different individual strategies of habitat selection, with some individuals placing home ranges in areas with high forest coverage while others occupying open areas. We found no effects of sex and body condition on habitat selection, and this could indicate that in the study area, both forested and non-forested cover types, such as open fields, shrub and anthropic areas, can provide adequate food, overhead cover and resting sites for all individuals. Pine marten ability to occupy open fields seems thus more related to the behavioural flexibility of the species, rather than to the need to supplement dens and forage from complementary lower quality habitat. The high quality of the Mediterranean continental area studied could also explain the selection of open areas by the pine marten. Our results offer useful information on pine marten ecology and may be helpful for conservation management of this species in southern Europe.  相似文献   

7.
The decline of the European hare Lepus europaeus populations has been shown to be correlated with agricultural intensification, which has caused loss of habitat heterogeneity. We aimed to investigate the diurnal spring habitat selection using Jacobs’ second selection index in an intensively cultivated farmland to reveal how the habitat choice by resting hares was affected by changes in the habitat availability. Clearance counts of hares driven out of known areas were made during an 11-year field investigation within two sectors of a private hunting ground located in the Paris basin (France). The loss of habitat heterogeneity included the disappearance of pastures dedicated to a last remaining sheep farm in the area, the removal of non-cropped areas and field boundaries and the increase of mean field size. Breeding stocks of hare declined during the study. Harrowed fields were always avoided. Pastures, alfalfa fields, thickets and fallow land were selected at the start of our study, whereas the remaining part was avoided at the end. The preference for ploughed fields decreased with the growth of vegetation in the winter-wheat fields. To benefit hares, land management should provide year-round vegetative cover and food from non-cropped areas in intensive arable farms.  相似文献   

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Den sites are critical resources that ultimately influence the population dynamics of many species. Little is known about cougar den selection, even though dens likely play important roles in cougar fitness and kitten survivorship. Thus, we aimed to describe cougar den site selection in the Southern Yellowstone Ecosystem (SYE) at two scales (third- and fourth-order resource selection) and within an ecological framework that included environmental characteristics, as well as some measure of prey availability and anthropogenic landscape features. We documented 25 unique dens between 2002 and 2013, and gathered data on microsite characteristics and paired random points for 20 dens. The timing of dens was clumped in summer, with 56 % of 25 dens beginning in June or July. Unexpectedly, female cougars in our study system exhibited third-order selection for den areas in less rugged terrain, but did not exhibit selection for greater or lesser access to hunting opportunity, roads, water, or specific habitat classes, as compared with the remainder of their home ranges. Instead, our findings suggested that third-order selection for den areas was much less important than fourth-order selection: cougar den sites were characterized by high concealment and substantial protective structure. Therefore, our results provided evidence in support of land practices that promote and protect downed wood and heavy structure on forest floors—these will best provide opportunities for cougars to find suitable den sites and maintain parturition behaviors.  相似文献   

10.
Habitat conversion and fire suppression during the last 50 yr have greatly reduced and altered Florida scrub vegetation, resulting in threats to the persistence of its unique flora. As part of a larger conservation project, we investigated patterns of isozyme variation in three rare perennial scrub plants with overlapping ranges endemic to Florida rosemary scrub on the Lake Wales Ridge. All three species have low levels of genetic variation, comparable to or lower than those generally reported for rare plants with restricted geographic ranges. Liatris ohlingerae has more than twice the expected heterozygosity of the other two species, with little population differentiation. In contrast, Hypericum cumulicola has highly differentiated populations with little apparent interpopulation gene flow and heterozygote deficiencies indicative of inbreeding. Eryngium cuneifolium, the species with the narrowest range and fewest populations, has intermediate values for genetic parameters. Although the three species have narrow and overlapping geographic ranges and similar habitat specificity, we discuss how optimal conservation of each species differs.  相似文献   

11.
After decades of suppression, fire is returning to forests of the western United States through wildfires and prescribed burns. These fires may aid restoration of vegetation structure and processes, which could improve conditions for wildlife species and reduce severe wildfire risk. Understanding response of wildlife species to fires is essential to forest restoration because contemporary fires may not have the same effects as historical fires. Recent fires in the Chiricahua Mountains of southeastern Arizona provided opportunity to investigate long‐term effects of burn severity on habitat selection of a native wildlife species. We surveyed burned forest for squirrel feeding sign and related vegetation characteristics to frequency of feeding sign occurrence. We used radio‐telemetry within fire‐influenced forest to determine home ranges of Mexican fox squirrels, Sciurus nayaritensis chiricahuae, and compared vegetation characteristics within home ranges to random areas available to squirrels throughout burned conifer forest. Squirrels fed in forest with open understory and closed canopy cover. Vegetation within home ranges was characterized by lower understory density, consistent with the effects of low‐severity fire, and larger trees than random locations. Our results suggest that return of low‐severity fire can help restore habitat for Mexican fox squirrels and other native wildlife species with similar habitat affiliations in forests with a historical regime of frequent, low‐severity fire. Our study contributes to an understanding of the role and impact of fire in forest ecosystems and the implications for forest restoration as fire returns to the region.  相似文献   

12.
Habitat loss is the greatest contributor to the decline of species globally. To prioritize protection of imperiled species, it is important to examine habitat use at multiple spatial scales because the availability of different resources and habitat features is scale dependent. We conducted a radio-telemetry study in the Long Point region of Ontario, Canada, in 2009 and 2010 to examine habitat selection at multiple spatial scales by eastern hog-nosed snakes (Heterodon platirhinos), a species at risk in Canada. We documented the habitat composition of home ranges compared to the surrounding landscape, the selection of locations within home ranges based on classified satellite imagery, and the use of microhabitat features based on site characterization in the field. At the scale of the home ranges, hog-nosed snakes avoided areas of agriculture and selected sand barrens. Within home ranges, hog-nosed snakes selectively used areas altered by humans (e.g., residential sites, openings in tree plantations). Microhabitats used by hog-nosed snakes had more woody debris, logs, and lower vegetative coverage than adjoining random sites. Because hog-nosed snakes prefer open areas and require sandy soils for nesting, management efforts should focus on the conservation and maintenance of sand barrens and patches of early successional forest. © 2021 The Wildlife Society.  相似文献   

13.
HedgehogsErinaceus europaeus Linnaeus, 1758 were radio-tagged and monitored during the summer of 2001 in a Danish rural area with the objective of quantifying home ranges, nightly distances travelled, habitat use, activity patterns, day-nesting habits, and body-weight changes of the five males and five females being recorded. Males had larger home-range sizes and travelled longer nightly distances than females. The two most common habitat types within the home ranges of the hedgehogs were deciduous forest and arable land, whereas the two most frequently used habitat types were deciduous forest and grassland. No differences between the sexes were found in the proportions of different habitat types within the home ranges or in habitat use. Non-random habitat use was found; forested areas and edge habitats seemed preferred to open areas. The most frequently used day-nesting habitat was deciduous forest. Foraging was by far the most time-consuming nightly activity for both sexes. Males lost weight during the study period (May–July), whereas females gained weight. A peak in the frequency of sexual behaviour was found from late-June to mid-July. The high level of male ranging activity and the weight loss of males are interpreted as a consequence of the promiscuous mating system of hedgehogs.  相似文献   

14.
Because of its crucial importance for the persistence of the endangered Tehuantepec jackrabbit (Lepus flavigularis), we identified structural characteristics of native vegetation (1) selected by Tehuantepec jackrabbits to establish home ranges, (2) used within home ranges, and (3) in relation to activity and inactivity periods. A neotropical savanna in the Isthmus of Tehuantepec, Oaxaca, México, offered diversity in native flora and heterogeneity in vegetation structure to the studied population of Tehuantepec jackrabbit. Adults and juveniles differed in habitat use patterns. No effect on habitat selection was detected for sex or season. Jackrabbits established home ranges on grassy habitat with discontinuous overstory of nanche (Byrsonima crassifolia) shrubbery and morro (Crescentia) trees. Adults underused dense vegetation where predators may ambush them; juveniles avoided dense vegetation and grassland without overstory. Within adults’ home ranges, habitat selection favoring grassy habitats with nanche and morro was relatively stronger during the activity period (nocturnal and crepuscular hours) and during one of 2 years which had more rainfall. Scattered trees and open shrubbery likely allowed foraging jackrabbits with both visibility and escape routes used to detect and outrun predators. Moreover, during the inactivity period (diurnal hours) adults and juveniles favored nanche shrubbery that provided resting jackrabbits with shelter to hide from predators. Clearly, structure and diversity of native vegetation in the savanna needs to be preserved for conservation of Tehuantepec jackrabbits because deteriorated habitat may pose higher predation rates for a jackrabbit population in risk of extirpation.  相似文献   

15.
This paper describes the use of farm dams by spur-winged geese (Plectropterus gambensis) on the Highveld of South Africa. Applications for mining rights on coal seams located under wetlands have increased, which raises the question whether the loss of the waterfowl habitat can be mitigated. Since the spur-winged geese were observed on natural wetlands and man-made farm dams, these birds were selected to determine whether they are compatible with dams. A transect of 145 km was traversed weekly with a vehicle from January 2013 to December 2014, to count geese on farmland at Heidelberg, Vaal Dam, Grootvlei and Balfour. The purpose was to describe (1) habitat use of geese on farmland, (2) the limitations of farm dams as offset habitats and (3) habitat improvement. The geese preferred natural wetlands over farm dams but foraged on arable land rather than natural grassveld. Spur-winged geese rest on farm dams during the rainy season, although these dams are not used for breeding or flightless moult and therefore can only be regarded as partial offset for natural wetlands. Increasing the area of shallows at the inflow of larger dams in open landscapes with fringing vegetation may encourage breeding. However, it may take 5–10 years for fringe vegetation to become established and attractive for breeding, meaning that an offset habitat cannot be created over the short term.  相似文献   

16.
Foraging behaviour and habitat selection occur as hierarchical processes. Understanding the factors that govern foraging and habitat selection thus requires investigation of those processes over the scales at which they occur. We investigated patterns of habitat use by African elephants (Loxodonta africana) in relation to vegetation greenness to investigate the scale at which that landscape attribute was most closely related to distribution of elephant locations. We analysed Global Positioning System radio-collar locations for 15 individuals, using the Normalized Difference Vegetation Index as a representation of vegetation greenness in a Geographic Information Systems framework. We compared the importance of vegetation greenness at three spatial scales: the total home range, the seasonal home range and the 16-day home range. During the wet season, seasonal home ranges for both sexes were associated with intermediate greenness within the total home range; there was no evidence of selection based on greenness at finer scales. During the dry season, the strongest associations were within the 16-day home range: individual locations for males tended to be in areas of intermediate greenness, and those for females were in areas of intermediate and high greenness. Our findings suggest that the role of vegetation greenness varies with the scale of analysis, likely reflecting the hierarchical processes involved in habitat selection by elephants.  相似文献   

17.
Mediterranean ecosystems are inherently patchy, challenging habitat-use behavior. Certain mammalian carnivores take advantage of this patchiness by a strategy of habitat complementation/supplementation, which is invariant to the scale of analysis. To test if the same behavior is adopted by the stone marten, we used a combined data set of capture and radio-tracking data at three scales of analysis (1-m, 25-m, and 452-m radius plots). We used compositional analysis to test if there were sex-specific differences in foraging and resting habitat use of stone martens and if these patterns were affected by the presence of other mesocarnivores. Our results showed that stone martens are found both in rural and forested landscapes. Foraging and resting activities occurred far from roads in large and complex patches of cork oak woodlands, riparian vegetation, orchards, and pastureland. Use varied with the scale of analysis and the sex. At smaller scales, females use pastures for foraging and orchards for resting, whereas riparian vegetation and sparse cork oak forests influenced this use at larger scales. Males, on the other hand, were more consistent across scales, using riparian areas and dense cork oak woodlands for foraging and pastures for resting. Stone martens shared the same areas with other coexisting mesocarnivores. Stone martens use cork oak woodlands and complement/supplement this use with other land cover types. The consistent use of cork oak woodlands across scales emphasizes the importance of this land cover to the preservation of functional Mediterranean ecosystems in southern Portugal.  相似文献   

18.
Understanding how animals utilize their habitat provides insights about their ecological needs and is of importance for both theoretical and applied ecology. As changing seasons impact prey habitat selection and vegetation itself, it is important to understand how seasonality impacts microhabitat choice in optimal foragers and their prey. We followed habituated bat‐eared foxes (Otocyon megalotis) in the Kalahari, South Africa, to study their seasonal habitat selection patterns and relate them to the habitat preferences of their main prey, termites (Hodotermes mossambicus). We used Resource Selection Functions (RSFs) to study bat‐eared foxes’ 3rd‐ and 4th‐order habitat selection by comparing used locations to random ones within their home ranges. Third‐order habitat selection for habitat type and composition was weak and varied little between seasons. We found that patterns of fox habitat selection did not mirror habitat selection of Hodotermes (quantified using RSFs), even when feeding on them (4th‐order). Taken together, these results might indicate that bat‐eared foxes’ food resources are homogenously distributed across habitats and that prey other than Hodotermes play an important role in bat‐eared foxes’ space use.  相似文献   

19.
Avian species diversity and territory location are often associated with sharp forest edges, or boundaries. However, our understanding of behaviours underlying avian distribution near forest boundaries, especially species with large home ranges, remains poor. In a two-year study, we measured chickadee flock movements in forests at 0–300 m from boundaries in an agricultural landscape near Edmonton, Alberta, Canada. Even though flocks foraged in all forested parts of the study area, only six of the 53 flocks studied foraged further from forest boundaries than expected if they had used their home range irrespectively of the distance to boundaries. We found no evidence that the association of chickadee flocks to forest boundaries resulted from vegetation changes near boundaries, or to changes in their foraging sites and foraging success near boundaries. However, chickadee flocks moved parallel to boundaries (<75 m away) twice as frequently as expected from random movement, thus suggesting that forest boundaries act as movement conduits. Even when birds do not apparently seek special features near forest boundaries, they may be closely associated with them, simply because their passive movements are constrained by habitat barriers defined by boundaries.  相似文献   

20.
Vegetation effects on phosphorus fractions in set-aside soils   总被引:1,自引:1,他引:0  
Jakob Magid 《Plant and Soil》1993,149(1):111-119
As increasing amounts of arable land are being set aside, it is of importance to study the effect of vegetation on soil fertility. The fractionation of soil P under grassland, beech and spruce vegetation was investigated in sites previously fertilized with P by extracting sequentially with Resin, NaHCO3, NaOH, HCl and finally NaOH after ultrasonic pretreatment. Under beech a large part of extractable P was found in inorganic fractions which are considered to be available for plants (Resin P1 and Bicarbonate P1). Under grass, a large part of the extractable P was found in potentially labile organic forms (Bicarbonate Po and Fulvic acid Po). After 25 years of permanent grass vegetation, the extractability of soil P was comparable to that from an adjacent arable plot. On spruce covered soils most of the added fertilizer P was rendered unextractable 20–30 years after application. However the available data does not allow a clear interpretation of this phenomena, as effects of soil parent material as well as vegetation may be taken into consideration. No decrease in P-extractability was found between beech and grass covered soils which had been fertilized for more than 200 years, when compared to less rich soils from the same area. On the basis of the current data it may be concluded that the vegetation affects the distribution of soil phosphorus fractions, and thus soil fertility. In the soils under investigation, grassland and beech vegetation conserved the phosphate availability to a high extent.  相似文献   

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