Use of space and habitats by meadow voles at the home range,patch and landscape scales

Using capture/recapture methods, we examined the spatial usage patterns of Microtus pennsylvanicus within and between experimentally created habitat patches of three sizes (1.0, 0.25 and 0.0625 ha) and between a 20-ha fragmented and a 20-ha continuous habitat landscape. We tested the prediction that home ranges near patch edges would be qualitatively different from those in patch interiors, and that the edge:interior habitat ratio could be used to make predictions concerning the dispersion and spatial use of individuals occupying different sized patches and between landscapes with different habitat structure. We found adult females on patch edges to have larger and more exclusive home ranges, larger body sizes, longer residence times, and to reproduce at a higher frequency than those in patch interiors. These edge effects also appeared to be largely responsible for the greater proportion of larger, reproductive females we found in small than larger patches and in the fragmented than in the continuous habitat (control) landscape. The selection of higher quality edge habitats by dominant females and the relegation of sub-dominants to patch interiors provides an explanation for the observed differences in the distribution and performance of females over patches and between landscapes.     

Response of a small felid of conservation concern to habitat fragmentation

Habitat loss and fragmentation are major drivers of biodiversity loss. A key question, particularly relevant to carnivore conservation, is to which extent species are able to survive in human-modified landscapes. Currently, conservationists are concerned about the impact habitat fragmentation may have on the long-term persistence of the forest-dwelling guiña (Leopardus guigna), given the increasingly modified landscapes in which they live. Here we evaluate the effect habitat cover, fragmentation and anthropogenic pressure have on the occupancy probability for guiñas in privately-owned forest fragments. We collected camera-trap data from 100 temperate rainforest sites in Chile and used single-season occupancy modeling to evaluate the influence of 13 parameters of landscape structure/anthropogenic pressure and four parameters of detection probability on the ocurrence of guiñas. The camera-trap survey data comprised 4168 camera-trap days and 112 independent records of guiñas. Surprisingly, fragmented (defined as having a high perimeter-to-area ratio) and moderately sized habitat patches best predicted site occupancy. Occupancy also increased where habitat patches were closer to continuous forest and nearer to buildings. Our results imply that guiñas can benefit from a high degree of edge type habitats in fragmented landscapes, capable of adapting to habitat fragmentation in the proximity to large continuous forest patches. This suggests that guiñas have a broader niche than previously believed. Additionally, the guiña is tolerant of human infrastructure. Further research is required to identify potential ecological traps, long-term source-sink dynamics, and the habitat loss/fragmentation threshold beyond which guiña populations are no longer viable.     

How fire interacts with habitat loss and fragmentation

Biodiversity faces many threats and these can interact to produce outcomes that may not be predicted by considering their effects in isolation. Habitat loss and fragmentation (hereafter ‘fragmentation’) and altered fire regimes are important threats to biodiversity, but their interactions have not been systematically evaluated across the globe. In this comprehensive synthesis, including 162 papers which provided 274 cases, we offer a framework for understanding how fire interacts with fragmentation. Fire and fragmentation interact in three main ways: (i) fire influences fragmentation (59% of 274 cases), where fire either destroys and fragments habitat or creates and connects habitat; (ii) fragmentation influences fire (25% of cases) where, after habitat is reduced in area and fragmented, fire in the landscape is subsequently altered because people suppress or ignite fires, or there is increased edge flammability or increased obstruction to fire spread; and (iii) where the two do not influence each other, but fire interacts with fragmentation to affect responses like species richness, abundance and extinction risk (16% of cases). Where fire and fragmentation do influence each other, feedback loops are possible that can lead to ecosystem conversion (e.g. forest to grassland). This is a well-documented threat in the tropics but with potential also to be important elsewhere. Fire interacts with fragmentation through scale-specific mechanisms: fire creates edges and drives edge effects; fire alters patch quality; and fire alters landscape-scale connectivity. We found only 12 cases in which studies reported the four essential strata for testing a full interaction, which were fragmented and unfragmented landscapes that both span contrasting fire histories, such as recently burnt and long unburnt vegetation. Simulation and empirical studies show that fire and fragmentation can interact synergistically, multiplicatively, antagonistically or additively. These cases highlight a key reason why understanding interactions is so important: when fire and fragmentation act together they can cause local extinctions, even when their separate effects are neutral. Whether fire–fragmentation interactions benefit or disadvantage species is often determined by the species' preferred successional stage. Adding fire to landscapes generally benefits early-successional plant and animal species, whereas it is detrimental to late-successional species. However, when fire interacts with fragmentation, the direction of effect of fire on a species could be reversed from the effect expected by successional preferences. Adding fire to fragmented landscapes can be detrimental for species that would normally co-exist with fire, because species may no longer be able to disperse to their preferred successional stage. Further, animals may be attracted to particular successional stages leading to unexpected responses to fragmentation, such as higher abundance in more isolated unburnt patches. Growing human populations and increasing resource consumption suggest that fragmentation trends will worsen over coming years. Combined with increasing alteration of fire regimes due to climate change and human-caused ignitions, interactions of fire with fragmentation are likely to become more common. Our new framework paves the way for developing a better understanding of how fire interacts with fragmentation, and for conserving biodiversity in the face of these emerging challenges.     

Foraging behaviour of the root vole Microtus oeconomus in fragmented habitats

The effect of habitat fragmentation on spatial foraging behaviour in the root vole Microtus oeconomus was investigated in seven experimental populations. Four of the populations were established in large, continuous blocks (30 × 95 m) of meadow habitat (treatment plots), whereas the three remaining populations had six small rectangular habitat fragments (30 × 7.5 m) with variable inter-fragment distances (control plots). Both the small habitat fragments and the large continuous habitat were embedded in a non-habitat matrix area which was regularly mowed. Half-way through the study period, the continuous habitat in treatment plots was destroyed by mowing to give a configuration identical to the control plots. Dyed bait placed at the edges and in the interior of habitat fragments as well as in the matrix area was used to reveal differential use of these areas for foraging. Animals in the small-fragment plots fed more than expected along the edges, while edges were used according to availability in the large blocks of continuous habitat. In the fragmented plots, the frequency of foraging in the matrix decreased with increasing distance to the fragment border and with increasing inter-fragment distances. Furthermore, the frequency of use of more than one habitat fragment in individual foraging ranges decreased with increasing inter-fragment distances. Reproductively inactive animals of both sexes fed more often along habitat edges than reproductively active animals. Reproductively active females fed exclusively in one habitat fragment, whereas inactive animals and especially reproductively active males frequently included more than one fragment in their foraging ranges. The only effect of habitat destruction was less foraging in the matrix habitat in the post-destruction treatment plots compared to the permanently fragmented control plots. This was probably an effect of different matrix quality. Root voles in these experimental populations forage in edge and matrix habitat with great risk of becoming victims to predation, and the results are interpreted in this context. Received: 19 August 1998 / Accepted: 30 June 1999     

Marten space use and habitat selection in managed coniferous boreal forests of eastern Canada

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     

Ranging Behavior of an Arboreal Marsupial in a Plantation Landscape

Forests are becoming increasingly fragmented, primarily because of their conversion to production landscapes. Animals occupying modified landscapes may need to expand their ranges and move longer distances between remnant forest patches to find resources. The establishment of plantations in fragmented landscapes, however, may provide complementary habitat for wildlife and improve connectivity, reducing the amount of movement required. Our objective was to determine the influence of plantations on koala (Phascolarctos cinereus) habitat use and test 2 competing hypotheses on the relationship between plantations and range size. We deployed global positioning system and very high frequency collars on 40 koalas in 2 landscapes (plantation and non-plantation) in Victoria, Australia. From 68,216 tracking points collected over an 8-month period, we calculated and compared seasonal home range size and habitat use between landscapes. There was no difference in range size, the size and number of core use areas, or the distance between core use areas between plantation and non-plantation landscapes. Plantations extend existing koala habitat and facilitate koala movement through a landscape; however, remnant native vegetation is still more frequently used. Consequently, native vegetation (even fragmented, linear roadside vegetation) is of high conservation importance for the persistence of koalas in modified landscapes. © 2020 The Wildlife Society.     

The behavioural ecology and population dynamics of a cryptic ground‐dwelling mammal in an urban Australian landscape

Urbanization results in widespread habitat loss and fragmentation and generally has a negative impact upon native wildlife, in particular ground‐dwelling mammals. The northern brown bandicoot (Isoodon macrourus; Marsupialia: Peramelidae) is one of relatively few native Australian ground‐dwelling mammals that is able to survive within urbanized landscapes. As a consequence of extensive clearing and urban development within the city of Brisbane, bandicoots are now restricted to the mostly small (<10 ha) bushland fragments scattered across the city landscape. Our study examined the behavioural ecology of northern brown bandicoots within habitat fragments located on a major creek‐line, using mark‐recapture population monitoring and radio telemetry. Bandicoots at monitored sites were found to occur at high densities (typically one individual ha^?1), although one‐third of the populations were transient. Radio tracking revealed that bandicoots had relatively small home ranges (mean 1.5 ± 0.2 ha) comprised largely of bushland/grassland with dense, often weed‐infested ground cover. Bandicoots sheltered by day in these densely covered areas and also spent most time foraging there at night, although they occasionally ventured small distances to forage in adjacent maintained parklands and residential lawns. We suggest that introduced tall grasses and other weeds contribute to high habitat quality within riparian habitat fragments and facilitate the persistence of high density populations, comprised of individuals with small home ranges. The generalized dietary and habitat requirements of northern brown bandicoots, as well as a high reproductive output, undoubtedly facilitate the survival of the species in urban habitat fragments. Further research is required on other native mammal species in urbanized landscapes to gain a greater understanding of how best to conserve wildlife in these heavily modified environments.     

Home range size scales to habitat amount and increasing fragmentation in a mobile woodland specialist

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Home range size of willow tits: a response to winter habitat loss

We examined the behavioral response to habitat loss and fragmentation of willow tits (Parus montanus) in winter in a mosaic forest landscape in northern Finland. We studied habitat preference, flock size and home range size of 16 flocks, half of which had their territories in forests fragmented by forestry and half in continuous forest. We predicted that birds would respond to habitat loss by enlarging their home range and/or diminishing group size. In addition, to compensate for fragmentation effects, willow tits might be expected to include more optimal habitat into their territories. Flocks included on average 3.9 birds and occupied territories of 12.6 ha. Willow tits avoided open areas (clear cuts and young sapling stands) and preferred mature forests and older sapling stands or pine bogs equally. Birds responded to habitat loss by enlarging their home ranges but not by reducing the group size. Large territories included a smaller proportion of mature forests, but the proportion of sapling and pine bog habitat did not change. Birds on territories that included a large proportion of open habitat localized their activity on several distinct habitat patches that were distributed over a wide area. We conclude that willow tits adjust territory use to compensate for the inclusion of unsuitable habitat within home ranges, and older sapling areas and pine bogs serve as surrogates for mature forests. However, birds did not enlarge the proportion of forest habitat in their territories with increasing habitat loss. Thus, our data do not suggest a strong effect of fragmentation, but imply that forestry practices reduce suitable wintering habitat and carrying capacity in the area. Thus winter habitat loss may explain the observed population decline of willow tits in Finland during recent decades.     

Patch occupancy by stone martens Martes foina in fragmented landscapes of central Spain: the role of fragment size,isolation and habitat structure

We studied the response to forest fragmentation of a generalist carnivore, the stone marten Martes foina, in highly fragmented landscapes of central Spain. Five different areas (n = 178 fragments) in central Spain were surveyed. This paper analyses the relationship between fragment use by martens (measured through scat presence) and a series of variables related to the size, isolation and vegetation structure of each fragment by means of stepwise logistic regression. Size and isolation have an important effect on stone marten presence in fragments. Our results were similar to those found for other marten species in landscapes with coarse-grain fragmentation, but they contrast with other studies conducted in landscapes with fine-grain fragmentation. These data suggested that in highly fragmented landscapes, size and isolation factors resulting from forest fragmentation were responsible for determining marten responses, irrespective of their habitat generalism. Management policies for the stone marten in highly fragmented scenarios require the maintenance of large forests near continuous forest tracts in mountains or riparian woodlands.     

Metapopulation extinction in fragmented landscapes: using bacteria and protozoa communities as model ecosystems

Extinction is notoriously difficult to study because of the long timescales involved and the difficulty in ascertaining that extinction has actually occurred. The effect of habitat subdivision, or fragmentation, on extinction risk is even harder to study, as it requires copious replication of habitat patches on large spatial scales and control of area effects between treatments. I used simple small-scale communities of bacteria and protozoa to study extinction in response to habitat loss and habitat fragmentation. I studied several different community configurations, each with three trophic levels. Unlike most metapopulation studies (experimental as well as theoretical), which have tended to deal with inherently unstable species interactions, I deliberately used community configurations that were persistent in large stock cultures. I recorded the time to extinction of the top predator in single habitat patches of different sizes and in fragmented systems with different degrees of subdivision but the same amount of available habitat. Habitat loss reduced the time to extinction of isolated populations. Fragmented systems went extinct sooner than corresponding unfragmented (continuous) systems of the same overall size. Unfragmented populations persisted longer than fragmented systems (metapopulations) with or without dispersal corridors between subpopulations. In fact, fragmented systems where the fragments were linked by dispersal corridors went extinctly significantly sooner than those where subpopulations were completely isolated from each other. If these results extend to more "natural" systems, it suggests a need for caution in management programs that emphasize widespread establishment of wildlife corridors in fragmented landscapes.     

Effect of habitat fragmentation on ranging behavior of white-headed langurs in limestone forests in Southwest China

The critically endangered white-headed langur (Trachypithecus leucocephalus) is confined to fragmented karst forests of southwest Guangxi Province, China. A lack of information on the influence of habitat fragmentation on langur behavior has prevented a comprehensive understanding of their ranging behavior and the development of effective langur conservation strategies. We collected comparative data on time budgets, daily path lengths, home range and diets of four langur groups inhabiting the lightly fragmented Fusui forest (G1, G2) and the more heavily fragmented Chongzuo forest (G3, G4). The aim was to explore the effect of this fragmentation on langur ranging behavior. Our results showed that the Fusui groups spent more time on moving and less time on feeding and playing than the Chongzuo groups. Daily path lengths were 472.4–536.1 m for the Fusui groups and 449.6–480.7 m for the Chongzuo groups, indicating no marked inter-site variation. The Fusui groups occupied much larger home ranges (23.8–33.8 ha) than the Chongzuo groups (14.5–15.8 ha). However, all groups had similar monthly home ranges. Diets significantly differed among langur groups. The Fusui groups consumed more young leaves and had much lower diet diversity compared with the Chongzuo groups. Our findings indicate that habitat fragmentation is one of the crucial determinants of white-headed langur ranging behavior because fragmentation reduces and restricts the home range. Langurs in fragmented habitat adopt an energy conservation strategy characterized by devoting more time to feeding and less time to moving, with a smaller home range and consumption of more plant species. We argue that linking fragmented forests with corridors should be considered a priority in a wider and comprehensive longer term langur population conservation and habitat management strategy.     

Diademed Sifaka (Propithecus diadema) Ranging and Habitat Use in Continuous and Fragmented Forest: Higher Density but Lower Viability in Fragments?

The mechanisms through which forest fragmentation threatens the survival of mammal populations remain poorly known, yet knowledge of this process would greatly aid conservation efforts. I investigated ranging behaviors of diademed sifakas ( Propithecus diadema ) in continuous and fragmented forest at Tsinjoarivo, eastern Madagascar, using focal animal observations to examine home range size, daily path length (DPL), and habitat use relative to forest edges over 12 mo. Sifaka groups in forest fragments had home ranges that were 25–50 percent as large as continuous forest groups, and moderately reduced DPLs. Continuous forest groups foraged more than expected near forest edges while fragment groups avoided edges. Fragments have higher population density than continuous forest; however, several lines of evidence suggest that fragment groups' food resources may be denser, but lower quality. Continuous forest groups appear to be energy-maximizers, maintaining large ranges and preferentially feeding in rare fruiting trees found only in continuous forest interiors, while fragment groups appear to be time-minimizers, using small home ranges and primarily feeding on mistletoe (a fallback food in continuous forest). Therefore, the consequences of fragmentation on long-term viability remain unknown; it is possible that the advantage of increased density is outweighed by longer-term demographic challenges, or other threats ( e.g. , nutrition, health, social behavior, disease). When animals stranded in forest fragments exhibit complex and potentially unpredictable responses, simple ecological proxies ( e.g. , incidence patterns and density) are probably inadequate in assessing population health and viability. Ecological study and monitoring is essential in judging the viability of fragmented populations.     

Effects of Habitat Quality and Seasonality on Ranging Patterns of Collared Brown Lemur (Eulemur collaris) in Littoral Forest Fragments

Degraded forest habitats typically show low fruit availability and scattered fruit tree distribution. This has been shown to force frugivorous primates either to move further in search of food, resulting in large home ranges, or to use energy saving strategies. Malagasy lemurs are known to face pronounced seasonality and resource unpredictability, which is amplified by the overall reduction in food availability due to the human-driven habitat disturbance on the island. To explore lemur flexibility to habitat disturbance, we examined the ranging behavior of collared brown lemurs (Eulemur collaris) in two differently degraded fragments of littoral forest of southeastern Madagascar. We collected data from February 2011 to January 2012 on two groups living in a degraded area and two groups living in a less disturbed forest. We calculated annual ranges, monthly ranges, and daily distance traveled. We then ran repeated measures ANOVAs using seasonality as dichotomous, intrasubject factor and site/group as intersubject nested factors. In the degraded forest, the lemurs had larger monthly ranges, and their annual ranges were either fragmented or characterized by multiple core areas. They were able to use a habitat mosaic that also included nonforested areas and swamps. In addition, they shortened their daily path length, possibly to preserve energy, and used different areas of their annual home ranges seasonally. Although a number of possible confounding factors may have been responsible for the observed differences between sites, our findings highlight the ranging flexibility of collared brown lemurs in littoral forest fragments.     

WeaselMustela nivalis spatial ranging behaviour and habitat selection in agricultural landscape

This paper reports the findings of a study on the spacing pattern of a population of weaselsMustela nivalis Linnaeus, 1758 in central Italy. We describe this pattern at spatial and habitat level, meant as a set of vegetational and environmental features. The study area is a typical agricultural landscape, consisting of highly fragmented natural habitat modified by thousands of years of human presence and work. The results indicate that individual home ranges vary greatly from non breeding to breeding season: during spring and summer, weasels increase their movements and the number of tracts they cross, which results in home range areas up to 10 times larger. Moreover this study demonstrates a strong preference of weasels for habitats formed by natural residual edges between fields and meadows. The shapes of the individual home ranges follow these edges, producing a typical linear spatial home range pattern.     

Effects of forest fragmentation on the lekking behavior of White-throated Manakins in Central Amazonia

Forest fragmentation can affect various aspects of population dynamics, but few investigators have assessed possible effects on the behavior of a species. Loss of habitat may limit population recruitment and abundance, which may alter breeding dynamics in forest remnants. We examined the lekking behavior of White-throated Manakins (Corapipo gutturalis) in a fragmented landscape to determine if forest fragmentation affected the spatial distribution of display courts and male behavior at courts. We captured and observed males at 19 courts located in 11 primary forests of different sizes in forest habitats of the Biological Dynamics of Forest Fragments Project area, an experimentally fragmented landscape located in the central Brazilian Amazon, and estimated their spatial distribution as the distance to the nearest court in the landscape. We quantified habitat loss using the proportion of forest cover surrounding courts and their distances to forest edges. No courts were detected in 1-ha forest fragments, suggesting direct effects from habitat loss following fragmentation that affected connectivity and thus recruitment and persistence of courts in the smallest fragments. The spatial distribution of display courts in forests larger than 10 ha remained unaltered, compared to display courts in continuous forests, but adult males were less numerous on courts with a higher percentage of forest cover and they displayed less on courts closer to forest edges. The spatial distribution of courts also contributed to variation in male social behavior, with more juvenile males present and adult males displaying at lower rates at more isolated courts. Although White-throated Manakins are locally common, the observed behavioral changes in response to habitat loss may affect their population dynamics. Our results show the importance of assessing behavioral changes in conservation programs and, in particular, of including biologically relevant measures of habitat loss in addressing its possible effects on species persistence in fragmented landscapes.     

Habitat fragmentation rather than habitat amount or habitat split reduces the diversity and abundance of ground-dwelling anurans within forest remnants of the Brazilian Cerrado

Rampant deforestation has caused the loss and fragmentation of natural habitats, which has precipitated a global biodiversity crisis. Research on how land-use change contributes to a loss of biodiversity is urgently needed, especially in ecosystems that have undergone rapid anthropogenic changes. We sought to investigate the extent to which habitat loss, fragmentation, and habitat split (the separation of forest and aquatic habitats) negatively influenced taxonomic diversity, functional diversity, total abundance, and the individual abundances of five anuran species in the Brazilian Cerrado. We sampled anurans between December 2017 and March 2018 using pitfall traps at sites distributed along a gradient of habitat fragmentation/habitat split: unfragmented forest, forest fragments without habitat split, and forest fragments with habitat split. Forest cover was measured within a 1-km radius of each site. Sites within unfragmented forests had higher taxonomic and functional diversities than either fragment type. Taxonomic diversity was highly correlated with functional diversity, but we did not find a pattern to the loss of functional traits. Total anuran abundance and the abundances of Chiasmocleis albopunctata, Physalaemus cuvieri, and Rhinella diptycha were higher in unfragmented forests compared to forest fragments. No species was more abundant in fragments than in unfragmented forests. Our results indicate that the fragmentation of forests by agricultural land use is directly and indirectly responsible for the loss of taxonomic and functional diversity, as well as for reducing population sizes of ground-dwelling anurans. Although we did not find a distinct effect of habitat split on ground-dwelling anurans, our study underscores the importance of preserving continuous forest habitats for the maintenance of anuran diversity in the Cerrado.     

The effects of habitat fragmentation on niche requirements of the marsh fritillary, Euphydryas aurinia, (Rottemburg, 1775) on calcareous grasslands in southern UK

The marsh fritillary, Euphydryas aurinia, has declined greatly in distribution across its range within Europe, resulting in its designation as a protected species under Annex II of the 1979 Bern Convention and the EC Habitats and Species Directive. The decline has been linked to a marked reduction in the extent of suitable calcareous and wet grassland habitats, habitats which have been lost through conversion of land to agriculture or urban areas, or reduced in quality due to inappropriate management. The UK is now one of the major strongholds for this butterfly in Europe, although much of the remaining habitat is small, isolated and highly fragmented. E. aurinia populations fluctuate greatly due to the combined effects of biotic (e.g. parasitoids) and abiotic (e.g. climate change) factors. We quantified the habitat associations of larval webs of E. aurinia on fragmented versus extensive (unfragmented) calcareous grassland habitat in southern England to test the hypothesis that habitat requirements of E. aurinia are more constrained within fragmented landscapes. Within both fragmented and unfragmented landscapes the quality and quantity of its main host plant in the UK, Succisa pratensis, was positively related to numbers of E. aurinia larval webs found. The sward height was also important at predicting the distribution of larval webs in both landscapes, although the heights were greater within sites in the unfragmented (≈20 cm) compared to fragmented (≈15 cm) landscape. We also found significant effects of elevation and the cover of bare ground on numbers of larval webs. Elevation was strongly correlated with the availability of host plant, whilst bare ground was only significant on sites within the fragmented landscape, showing a negative relationship with number of larval webs. Our results further emphasise the importance of not only maintaining the habitat quality of extant calcareous grassland sites for E. aurinia in the UK, but also increasing the size and connectivity of these sites to increase the chances and rate of (re)colonisation of unoccupied but suitable habitat. In addition, we show that the habitat requirements of E. aurinia on sites in a large unfragmented landscape may be less specific and thus require less extensive management than that required to create optimal conditions necessary at smaller, more isolated sites in fragmented landscapes.     

Survival strategies of a frugivore,the sun bear,in a forest-oil palm landscape

As large areas of forest are lost throughout the tropics, prime habitat of many species decline and become fragmented. The island of Borneo is a prime example, with accelerated clearing of forests primarily for oil palm expansion. Borneo is recognized as an important stronghold for the conservation of the sun bear (Helarctos malayanus), but it is unclear how habitat reduction and fragmentation is affecting this frugivore. We used camera traps and sign surveys to understand patterns of sun bear habitat use in a matrix of fragmented forests and extensive oil palm development, which has existed as such for?>?15 years: the Lower Kinabatangan floodplain in Sabah, Malaysian Borneo. Within these small forest fragments, squeezed between a major river and oil palm plantations, bears exhibited selection for areas farther from human activity (plantations, river boat traffic, and buildings), and were rarely active during the day, demonstrating both spatial and temporal avoidance of potential human-related threats. They selected large trees to feed and rest, and also exploited adjacent plantations to feed on oil palm fruits. We conclude that even relatively small forest fragments (~?2000 ha) within large agricultural landscapes can be important for sun bears. Our research highlights the remarkable adaptations this species has employed to persist in a drastically modified landscape.