Behaviour-Related Scalar Habitat Use by Cape Buffalo (Syncerus caffer caffer)

Studies of habitat use by animals must consider behavioural resource requirements at different scales, which could influence the functional value of different sites. Using Cape buffalo (Syncerus caffer caffer) in the Okavango Delta, Botswana, we tested the hypotheses that behaviour affected use between and within habitats, hereafter referred to as macro- and microhabitats, respectively. We fitted GPS-enabled collars to fifteen buffalo and used the distances and turning angles between consecutive fixes to cluster the resulting data into resting, grazing, walking and relocating behaviours. Distance to water and six vegetation characteristic variables were recorded in sites used for each behaviour, except for relocating, which occurred too infrequently. We used multilevel binomial and multinomial logistic regressions to identify variables that characterised seasonally-preferred macrohabitats and microhabitats used for different behaviours. Our results showed that macrohabitat use was linked to behaviour, although this was least apparent during the rainy season, when resources were most abundant. Behaviour-related microhabitat use was less significant, but variation in forage characteristics could predict some behaviour within all macrohabitats. The variables predicting behaviour were not consistent, but resting and grazing sites were more readily identifiable than walking sites. These results highlight the significance of resting, as well as foraging, site availability in buffalo spatial processes. Our results emphasise the importance of considering several behaviours and scales in studies of habitat use to understand the links between environmental resources and animal behavioural and spatial ecology.     

Seasonal fluctuations of resource abundance and avian feeding guilds across forest–farmland boundaries in tropical Africa

Seasonal fluctuations in climatic factors are expected to increase in future decades. However, little is known about the response of tropical species communities to seasonal fluctuations in climate and resource availability, particularly across different habitat types. We examined the relationship between spatio‐temporal fluctuations in the abundance of fruits and invertebrates and two avian feeding guilds, i.e. frugivores and insectivores, in forest and farmland habitats in western Kenya. Fruits and invertebrates fluctuated substantially throughout the year, but seasonal fluctuations were asynchronous between the two habitat types. Species richness and total abundance of frugivores and insectivores also fluctuated strongly and were closely related to the abundance of their respective resources. Frugivore species richness fluctuated anti‐cyclical in forest and farmland habitats, suggesting that several frugivorous species tracked fruit resources across habitat boundaries. In contrast, insectivorous bird richness fluctuated synchronously in the two habitat types, suggesting a lack of local‐scale movements across habitat boundaries. We conclude that bird communities strongly respond to seasonal fluctuations in resource availability, but responses differ between feeding guilds. While frugivores seem to respond flexibly to seasonal fluctuations, for instance by tracking fruit resources across habitat boundaries, insectivorous birds appear to be more susceptible to the expected increase in seasonal fluctuations in resource availability.     

Functional responses in polar bear habitat selection

Habitat selection may occur in situations in which animals experience a trade-off, e.g. between the use of habitats with abundant forage and the use of safer retreat habitats with little forage. Such trade-offs may yield relative habitat use conditional on the relative availability of the different habitat types, as proportional use of foraging habitat may exceed proportional availability when foraging habitat is scarce, but be less than availability when foraging habitat is abundant. Hence, trade-offs in habitat use may result in functional responses in habitat use (i.e. change in relative use with changing availability). We used logistic and log-linear models to model functional responses in female polar bear habitat use based on satellite telemetry data from two contiguous populations; one near shore inhabiting sea ice within fjords, and one inhabiting pelagic drift ice. Open ice, near the ice edge, is a highly dynamic habitat hypothesised to be important polar bear habitat due to high prey availability. In open ice-polar bears may experience a high energetic cost of movements and risk drifting away from the main ice field (i.e. trade off between feeding and energy saving or safety). If polar bears were constrained by ice dynamics we therefore predicted use of retreat habitats with greater ice coverage relative to habitats used for hunting. The polar bears demonstrated season and population specific functional responses in habitat use, likely reflecting seasonal and regional variation in use of retreat and foraging habitats. We suggest that in seasons with functional responses in habitat use, polar bear space use and population distribution may not be a mere reflection of prey availability but rather reflect the alternate allocation of time in hunting and retreat habitats.     

Temporal patterns of crop raiding by elephants: a response to changes in forage quality or crop availability?

Temporal patterns of crop raiding by elephants were studied for 13 months in 1996/1997 at Kibale Forest National Park, Uganda. To determine the influence of environmental factors on the timing of raiding, we tested for correlations between crop raiding patterns and the quality of natural forage within the forest as well as crop availability beyond park boundaries. Crop raiding occurred throughout the year with peaks in dry seasons when crop availability was high. Bananas and maize were the main crops raided. Variations in forage quality were moderate with small seasonal fluctuations and peaks in dry seasons. Monthly crop raiding incidences were not influenced by forage quality but by ripening of maize. Comparison of forage quality and temporal distribution of crop raiding between savanna and forest habitats suggests that crop availability is more important in forest habitats, whereas in savanna habitats large seasonal fluctuations in forage quality have a greater influence on temporal patterns of crop raiding.     

How landscape scale changes affect ecological processes in conservation areas: external factors influence land use by zebra (Equus burchelli) in the Okavango Delta

Most large‐bodied wildlife populations in sub‐Saharan Africa only survive in conservation areas, but are continuing to decline because external changes influence ecological processes within reserves, leading to a lack of functionality. However, failure to understand how landscape scale changes influence ecological processes limits our ability to manage protected areas. We used GPS movement data to calculate dry season home ranges for 14 zebra mares in the Okavango Delta and investigated the effects of a range of landscape characteristics (number of habitat patches, mean patch shape, mean index of juxtaposition, and interspersion) on home range size. Resource utilization functions (RUF) were calculated to investigate how specific landscape characteristics affected space use. Space use by all zebra was clustered. In the wetter (Central) parts of the Delta home range size was negatively correlated with the density of habitat patches, more complex patch shapes, low juxtaposition of habitats and an increased availability of floodplain and grassland habitats. In the drier (Peripheral) parts of the Delta, higher use by zebra was also associated with a greater availability of floodplain and grassland habitats, but a lower density of patches and simpler patch shapes. The most important landscape characteristic was not consistent between zebra within the same area of the Delta, suggesting that no single foraging strategy is substantially superior to others, and so animals using different foraging strategies may all thrive. The distribution and complexity of habitat patches are crucial in determining space use by zebra. The extent and duration of seasonal flooding is the principal process affecting habitat patch characteristics in the Okavango Delta, particularly the availability of floodplains, which are the habitat at greatest risk from climate change and anthropogenic disturbance to the Okavango's catchment basin. Understanding how the factors that determine habitat complexity may change in the future is critical to the conservation of large mammal populations. Our study shows the importance of maintaining flood levels in the Okavango Delta and how the loss of seasonal floodplains will be compounded by changes in habitat configuration, forcing zebra to change their relative space use and enlarge home ranges, leading to increased competition for key resources and population declines.     

Habitat change in braided flood plains (Tagliamento, NE-Italy)

1. Relative changes and age distribution of habitats were investigated in the active channel of a bar‐braided and an island‐braided reach of the Tagliamento River (NE‐Italy). Between September 1999 and January 2002, six habitat types were delineated with a differential Global Positioning System on five dates following floods of different magnitude. Overlay maps were employed to calculate age and relative change of habitats. We established exponential decay rates (k‐values) for islands and major aquatic habitats. 2. Relative changes of all aquatic habitats combined were up to 82% between survey dates in the bar‐braided flood plain, with a cumulative rate of 85% over the 2.5‐year period. Relative habitat changes in the island‐braided flood plain were lower with a cumulative change of almost 60% during the study period. In the bar‐braided flood plain significant exponential decay relationships were established for channels, alluvial channels, backwaters, and ponds. 3. Half‐lives were particularly short for backwaters and ponds. In the island‐braided reach, significant relationships existed for channels and alluvial channels. The half‐lives of channels and alluvial channels increased with the presence of vegetated islands. Relative habitat composition within the active corridor remained almost constant, supporting the applicability of the shifting mosaic steady state model to braided floodplain ecosystems. 4. Our results indicate that under natural conditions aquatic floodplain habitats can be highly dynamic over short time‐scales. Even small water level fluctuations (‘flow pulses’) can lead to major habitat changes with important consequences for the fauna and flora.     

Temporal scales of density‐dependent habitat selection in a large grazing herbivore

Habitat selection is a density‐dependent process, but little is known regarding how this relationship may vary across different temporal scales. Over long time scales, grazing shapes the structure, diversity and functioning of terrestrial ecosystems, and grazing‐induced changes in forage production over time are likely to affect the level of density dependence in habitat selection. In this fully‐replicated, landscape‐scale experiment, we investigated how density‐dependent habitat selection by a large grazing herbivore, sheep Ovis aries, develops over the time scale of a decade. We also address an often‐neglected challenge in habitat selection studies; namely, whether there is variation in use within a particular habitat or vegetation type and why. We found clear evidence of density dependence in habitat selection, with a wider use of habitats at high density. Despite a change in the standing biomass of high‐productivity vegetation at high herbivore density over the years, with herb biomass declining and graminoid biomass increasing, there was no clear evidence that these grazing‐induced changes in habitat over the years were strong enough to affect the level of density‐dependent habitat selection. The difference in selection for high versus low‐productivity habitats remained similar, despite annual fluctuations in the strength of selection. We found strong variation in selection within each vegetation type, even when vegetation types were mapped at a fine‐resolution scale. Our study shows that despite the interactive effects of herbivores and habitats, they are not always sufficiently strong enough to affect the level of density‐dependent habitat selection.     

The impacts of landscape structure on the winter movements and habitat selection of female red deer

An area of research that has recently gained more attention is to understand how species respond to environmental change such as the landscape structure and fragmentation. Movement is crucial to select habitats but the landscape structure influences the movement patterns of animals. Characterising the movement characteristics, utilisation distribution (UD) and habitat selection of a single species in different landscapes can provide important insights into species response to changes in the landscape. We investigate these three fields in female red deer (Cervus elaphus) in southern Sweden, in order to understand how landscape structure influences their movement and feeding patterns. Movements are compared between two regions, one dominated by a fragmented agriculture–forest mosaic and the other by managed homogenous forest. Red deer in the agriculture-dominated landscape had larger UDs compared to those in the forest-dominated area, moved larger distances between feeding and resting and left cover later in the day but used a similar duration for their movements, suggesting faster travelling speeds between resting and feeding locations. The habitat selection patterns of red deer indicate a trade-off between forage and cover, selecting for habitats that provide shelter during the day and forage by night. However, the level of trade-off, mediated through movement and space use patterns, is influenced by the landscape structure. Our approach provides further understanding of the link between individual animal space use and changing landscapes and can be applied to many species able to carry tracking devices.     

The effects of depth and salinity on juvenile Chinook salmon Oncorhynchus tshawytscha (Walbaum) habitat choice in an artificial estuary

The energetic cost for juvenile Chinook salmon Oncorhynchus tshawytscha to forage in habitats of different salinity and depth was quantified using a behavioural titration based on ideal free distribution theory. When given a choice between freshwater habitats of different depths (>0·83 or <0·83 m), a greater proportion of fish used the deeper habitat. When the deeper habitat was saltwater, the proportion of fish using it increased. When food was added to both the shallow freshwater and deep saline habitats, however, fish distribution returned to that observed when both habitats were fresh water. This indicates that the preference for deep saline habitats during the stratified phase was driven by some benefit associated with residency in deeper water, rather than salinity. The low perceived cost of low salinity might be in part due to the fish's ability to minimize this cost by only making brief forays into the alternate freshwater habitat. When the food ration delivered to the more costly, shallow habitat was 50% greater than that delivered to the less costly, deep habitat, fish distributed themselves equally between the two habitats, presumably because of equal net benefits. This study demonstrates that juvenile Chinook salmon prefer deep saline habitat to shallow freshwater habitats but will make brief forays into the freshwater habitat if food availability is sufficiently high.     

Dung beetle assemblages in primary forest and disturbed habitats in a tropical dry forest landscape in western Mexico

Dung beetles (Scarabaeinae) are conspicuous components in most terrestrial ecosystems, performing important ecological functions and services. Being sensitive to several types of disturbance, they have been successfully used as indicators of habitat change. Dung beetle communities in tropical rainforests have been well studied, but considerably less information is available for tropical dry forests. In this study I sampled dung beetles in two undisturbed habitats, deciduous forest and semideciduous forest, and two disturbed habitats, secondary forest and open area habitat, in the Chamela-Cuixmala region of western Mexico. Dung beetle species with high indicator value for each habitat were identified. Beetle abundance, observed species richness and estimated species richness were similar in the three forest habitats, but significantly lower in the open area habitat. A more detailed analysis of species-specific abundances in the three forest habitats revealed some differences. Transects of one of the undisturbed habitats, the deciduous forest, were more similar to the non-adjacent transects of disturbed secondary forest, than to the adjacent undisturbed semideciduous forest transects. Unlike studies in other tropical sites that have found a decrease in equitability in Scarabaeinae assemblages between undisturbed forest and disturbed habitat (particularly open habitats), in the Chamela-Cuixmala region all four habitats showed similar low equitability in community structure, with two or three very dominant species.     

Vegetation quality and habitat selection by European haresLepus europaeus in a pastural landscape

European haresLepus europaeus Pallas, 1778 have lower population densities and body condition in pastural landscapes than in arable landscapes, but reasons for this are not understood. The aim of this study was to determine whether forage quality is low in pastural landscapes during certain seasons. We carried out chemical analysis of the nutritional quality of 5 habitat types to determine whether hares select high quality habitats, and whether nutritional quality explains seasonal differences in range sizes of hares in pastural landscapes. Hares did not tend to select habitats of high nutritional quality (protein, fat or energy) over those of lower quality. Hares did not increase active range size as the overall energy content of forage at the study site decreased; seasonal differences in active range size were not explained by nutritional quality. Differences may be explained by behavioural changes related to breeding. Pastural habitat is fairly stable in terms of nutritional quality through the year, and results suggest that poor forage quality is unlikely to be responsible for the poor body condition of hares in pastural landscapes. Hares in these landscapes are more likely to be limited by habitat quality in terms of cover than by forage.     

Comparative dynamics of small mammal populations in treefall gaps and surrounding understorey within Amazonian rainforest

Variation in food resource availability can have profound effects on habitat selection and dynamics of populations. Previous studies reported higher food resource availability and fruit removal in treefall gaps than in the understorey. Therefore, gaps have been considered "keystone habitat" for Neotropical frugivore birds. Here we test if this prediction would also hold for terrestrial small mammals. In the Amazon, we quantified food resource availability in eleven treefall gaps and paired understorey habitats and used feeding experiments to test if two common terrestrial rodents ( Oryzomys megacephalus and Proechimys spp.) would perceive differences between habitats. We live-trapped small mammals in eleven gaps and understorey sites for two years, and compared abundance, fitness components (survival and per capita recruitment) and dispersal of these two rodent species across gaps and understorey and seasons (rainy and dry). Our data indicated no differences in resource availability and consumption rate between habitats. Treefall gaps may represent a sink habitat for Oryzomys where individuals had lower fitness, apparently because of habitat-specific ant predation on early life stages, than in the understorey, the source habitat. Conversely, gaps may be source habitat for Proechimys where individuals had higher fitness, than in the understorey, the sink habitat. Our results suggest the presence of source-sink dynamics in a tropical gap-understorey landscape, where two rodent species perceive habitats differently. This may be a mechanism for their coexistence in a heterogeneous and species-diverse system.     

景观基质对雅江中游河谷黑颈鹤冬季觅食地选择的影响

生态系统中生境斑块并非孤立存在,而是嵌于周边景观基质中。生境内种群赖以生存的资源和环境条件不仅取决于生境本身,更与景观基质组成与结构紧密关联。黑颈鹤是青藏高原的旗舰物种,雅鲁藏布江中游河谷高寒湿地是全球最大的黑颈鹤越冬地,为其提供了良好的觅食生境。厘清该区域黑颈鹤觅食生境选择如何受景观基质组成结构的影响,对于青藏高原旗舰物种保护以及流域生态系统综合治理具有重要意义。运用景观生态学原理,以遥感影像和实地黑颈鹤种群调查数据为基础,结合景观基质多尺度缓冲区构建、相关分析以及Maxent模型,分析2000-2020年雅江中游河谷黑颈鹤国家级自然保护区（日喀则片区）景观格局时空变化和觅食地生境特征及其与黑颈鹤种群的关系,探究景观基质对黑颈鹤觅食地选择的影响,并利用关键生境因子模拟黑颈鹤生境适宜性分布。通过分析发现：（1）时间尺度上,雅江中游河谷耕地面积先增加后下降,滩地持续减少;空间尺度上,觅食黑颈鹤种群呈东多西少的集群分布特征,其分布范围与河谷内耕地分布基本吻合;（2）景观基质对黑颈鹤觅食地选择影响显著。景观结构上,黑颈鹤偏好连通性好、优势度高的景观基质;景观组成上,偏好基质中耕地和水域类型,这与黑颈鹤的觅食习性及对环境安全的生态位需求有关;（3）景观基质结构组成对黑颈鹤觅食地选择的影响具有显著的尺度效应。景观基质结构影响最显著的空间尺度为1500-2000m。但基质中耕地、草地和水域等景观组成要素对黑颈鹤的影响具有不同空间尺度效应,分别为1500m、3000m和4000m;（4）通过模型模拟,揭示出黑颈鹤适宜生境面积先增后减,但总体较2000年呈上升趋势,且基质中觅食地与耕地的距离、水域斑块密度和偏好景观组成的优势度始终是生境适宜性解释率最高的景观因子。本研究揭示出,该区域乡村规划应该统筹优化黑颈鹤栖息生境及其景观基质中的作物生产以及居民生活,形成以黑颈鹤旗舰物种保护为核心的高寒湿地生态系统综合管理模式,从而增强青藏高原高寒生态系统的稳定性和可持续性,同时也为深入研究物种生境选择机制提供了思路。     

Evolutionary dynamics of habitat use

I examine the evolution of alternate genotypes that use two habitats that differ in vegetative cover, focusing on the interplay between ecological dynamics of the community and changes in selective advantage. Facultative habitat choice can stabilize a predator population that would cycle if isolated in the more open habitat. This has important implications for the evolution of habitat use strategies. Local stability arising from facultative habitat use allows any number of behavioural genotypes to co-exist: selective use of the open habitat, selective use of the dense habitat, opportunistic use of both habitats in proportion to availability, and facultative switching between habitats to maximize energy gain. Co-existence occurs because the fitness landscape is flat at the ecological equilibrium imposed by the facultative genotype. In contrast, ecological instability favours the evolution of genotypes with behavioural flexibility to avoid being in the wrong place at the wrong time or selective exploitation of one of the habitats. Uncertain information about habitat quality erodes the adaptive advantage of otherwise optimal behaviours, favouring a bet-hedging behavioural strategy synonymous with partial habitat preferences. These results suggest that ecological dynamics could have a strong influence on behavioural heterogeneity within forager populations and that a mixed ESS for habitat use should predominate.     

Experimental evidence of density dependent activity pattern of a large herbivore in an alpine ecosystem

Density dependent processes affecting foraging strategies may in turn influence vital rates and population regulation in large herbivores. Increased competition may lower both forage availability and quality, but whether the main activity constraint at high density is increased searching time or increased digestion time is poorly investigated. In a fully replicated landscape‐scale experiment, we used long‐term data (2003–2009) from domestic sheep grazing at high and low density (80 and 25 sheep km^–2, respectively) on alpine summer ranges to test density dependence in allocation of time to feeding (moving) vs digestion (resting) activities and how this in turn affected body growth. Sheep at high density spent more time actively feeding than sheep at low density, but sheep moved shorter distances while foraging at high density. Increased activity levels at high density suggest that the main activity constraint at high density was availability of high‐quality food increasing searching time and possibly reducing intake rates. Increased movement distances at low density is consistent with a higher selection for more productive vegetation types since high‐quality patches are dispersed in the landscape. The alternative hypothesis, that food processing time increased at high density was not supported as it would have reduced overall activity levels. Individual activity levels increased body growth, but this was not sufficient to fully compensate for lower habitat quality leading to an overall reduced body growth at high density. Our experiment clearly documents changes in activity budgets and movement distances of a large herbivore at high population density, providing one potential behavioural mechanism of density dependent responses observed in vital rates.     

Finding food in a highly seasonal landscape: where and how pink footed geese Anser brachyrhynchus forage during the Arctic spring

Food accessibility and availability in the highly seasonal Arctic landscape can be restricted by snow cover and frozen substrate, particularly in early spring. Therefore, to determine how a long distance migratory herbivore forages in such a landscape, pink‐footed geese Anser brachyrhynchus at an early spring feeding area in Svalbard were studied. Birds arrived in mid May when extensive snow cover restricted habitat availability. Geese fed in all habitats, but the highest densities occurred in wet tundra. However, prolonged snow lie restricted access to wet areas compared to dry and mesic habitats. Above ground biomass was very low in all habitats; yet sizeable amounts occurred below ground. In line with this, the majority of birds (86%) grubbed for below ground plant storage organs such as stem bases and rhizomes. Wet habitat contained greater quantities of edible and lower amounts of inedible below ground material (ratio 1:0.3) than dry (ratio 1:9) or mesic (ratio 1:4) areas. Although foraging in wet habitat prevented geese from encountering high proportions of inedible plant parts, forage species characteristic of this habitat, such as Dupontia grasses and the rush Eriophorum scheuchzeri, were more difficult to extract than food plants typical of drier habitats such as the forb Bistorta vivipara. Hence, we suggest that wet areas are preferred by pink‐footed geese, but the prolonged snow lie there made it necessary to use less preferred but much more abundant drier habitats, which experienced earlier snowmelt and indeed accommodated more than half of all goose foraging recordings.     

Female Moose Prioritize Forage Over Mortality Risk in Harvested Landscapes

Since 2010, several moose (Alces alces) populations have declined across North America. These declines are believed to be broadly related to climate and landscape change. At the western reaches of moose continental range, in the interior of British Columbia, Canada, wildlife managers have reported widespread declines of moose populations. Disturbances to forests from a mountain pine beetle (Dendroctonum ponderosae) outbreak and associated salvage logging infrastructure in British Columbia are suspected as a mechanism manifested in moose behavior and habitat selection. We examined seasonal differences in moose habitat selection in response to landscape change from mountain pine beetle salvage logging infrastructure: dense road networks and large intensive forest harvest cutblocks. We used 157,447 global positioning system locations from 83 adult female moose from 2012 to 2016 on the Bonaparte Plateau at the southern edge of the Interior Plateau of central British Columbia to test whether increased forage availability, landscape features associated with increased mortality risk, or the cumulative effects of salvage logging best explain female moose distribution using resource selection functions in an information-theoretic framework. We tested these hypotheses across biological seasons, defined using a cluster analysis framework. The cumulative effects of forage availability and risk best predicted resource selection of female moose in all seasons; however, the covariates included in the cumulative models varied between seasons. The top forage availability model better explained moose habitat use than the top risk model in all seasons, except for the calving and fall seasons where the top risk model (distance to road) better predicted moose space use. Selection of habitat that provides forage in winter, spring, and summer suggests that moose seasonally trade predation risk for the benefits of foraging in early seral vegetation communities in highly disturbed landscapes. Our results identified the need for intensive landscape-scale management to stem moose population declines. Additional research is needed on predator densities, space use, and calf survival in relation to salvage logging infrastructure. © 2020 The Wildlife Society.     

Vegetation dynamics in temporary and shallow freshwater habitats

The vegetation dynamics in habitats subject to large seasonal fluctuations in water level has been reconsidered in the light of the availabe literature on the ecological requirements of the plants which occur in different ecophases in these habitats. It is suggested that the water-level change is a component of the normal environment for the vegetation of such habitats, and that the changes in the community structure simply reflect the oscillating shifts in the dominance of various constituent species of an otherwise stable community which is adapted to the particular habitat conditions.     

Spatiotemporal drivers of energy expenditure in a coastal marine fish

Animal behavior and energy expenditure often vary significantly across the landscape, and quantifying energy expenditure over space and time provides mechanistic insight into ecological dynamics. Yet, spatiotemporal variability in energy expenditure has rarely been explored in fully aquatic species such as fish. Our objective was to quantify spatially explicit energy expenditure for a tropical marine teleost fish, bonefish (Albula vulpes), to examine how bonefish energetics vary across landscape features and temporal factors. Using a swim tunnel respirometer, we calibrated acoustic accelerometer transmitters implanted in bonefish to estimate their metabolic rates and energy expenditure, and applied this technology in situ using a fine-scale telemetry system on a heterogeneous reef flat in Puerto Rico. Bonefish energy expenditure varied most among habitats, with significant interactions between habitat and temporal factors (i.e., diel period, tide state, season). The energy expenditure was generally highest in shallow water habitats (i.e., seagrass and reef crest). Variation in activity levels was the main driver of these differences in energy expenditure, which in shallow, nearshore habitats is likely related to foraging. Bonefish moderate energy expenditure across seasonal fluctuations in temperature, by selectively using shallow nearshore habitats at moderate water temperatures that correspond with their scope for activity. Quantifying how animals expend energy in association with environmental and ecological factors can provide important insight into behavioral ecology, with implications for bioenergetics models.     

Patterns of frugivory of the Budongo Forest chimpanzees, Uganda

Frugivory patterns of the chimpanzees in the Budongo Forest Reserve, Uganda were studied between June 2000 and August 2001. Chimpanzee feeding habitats, movement, group size and food eaten were assessed using focal and scan sampling. It was found that fruits were scarce during the dry season, when chimpanzees appeared and moved in large groups over long distances and raided farms at the forest edge. Chimpanzee movement out of the forest to forage was influenced by seasonal fluctuations in availability of preferred foods as some cultivated crops are perennial. Presence of chimpanzees in a specific feeding habitat was related to the availability of edible fruits both within and between months, suggesting that the presence of food may influence chimpanzee movement patterns. Therefore, a good understanding of patterns of frugivory is essential for making informed decisions about conservation of chimpanzees and other frugivores like birds and monkeys in Budongo as different forest habitats are under varying human pressure because of logging and other forms of utilization.