Home Range Overlap Research Articles

Movement patterns and herd dynamics among South African giraffes (Giraffa camelopardalis giraffa)

AbstractGiraffes reside in a fission–fusion social system, with sex, age proximity, kinship and home range overlap accounting for some of the variance in herd composition, while season, sex, age and time of day influence diet, home range size and distance travelled. To increase our knowledge of habitat use and fission–fusion herd dynamics, we placed GPS devices on eight adult female South African giraffes (Giraffa camelopardalis giraffa) living in the Khamab Kalahari Nature Reserve (South Africa). We tested four predictions about how season, kinship, home range and travel patterns influence habitat use and herd dynamics. Our two key findings were that females with a greater degree of home range overlap were more likely to form herds, but the degree of overlap was independent of the amount of time that they spent together in a herd, and that on the day prior to herd formation, females travelled about twice as far as their daily average and tended to move directly towards their future herd mate. We conclude that habitat use and movement patterns regulating fission–fusion dynamics reflect an interaction of ecological, social and reproductive factors operating in tandem, not independently.

First Evidence of Mutually Exclusive Home Ranges in the Two Main Colonies of Lesser Kestrels in Italy

Animals compete for resources, and one way to ensure access to resources is by excluding competitors from the area containing the resources. Advances in tracking technology make it possible to quantify the overlap in home ranges between individuals and between populations. We present the first evidence of space partitioning between the two main Lesser Kestrel Falco naumanni colonies with the highest numbers of individuals in Italy, and with the highest densities of Lesser Kestrels in inhabited areas in their Eurasian breeding range. Using GPS data loggers, we collected 41,126 GPS points of Lesser Kestrels from both colonies during the nestling period. Home range overlap between the two colonies was almost zero at both 100%- and 99%-isopleths, and zero at 95%- and 90%-isopleths. Using a randomization procedure, we could show that home ranges were more spatially-segregated than expected by chance. We did detect increased overlap in home ranges among individuals within colonies. Although our results require further confirmation, they suggest that competition for food between colonies is weaker due to this strategy of spatial segregation of foraging areas. Our study confirms the recent notion that between-colony areal segregation may be the norm in colonial central-place foragers.

Spatial and temporal interactions of free-ranging pacas (Cuniculus paca)

Although the paca is the most frequently hunted game species throughout the Neotropics, its behavioral and ecological requirements remain poorly understood. Here, we describe ranging behavior, spatio-temporal intraspecific interactions, and cavity use within a mosaic landscape in Central Belize, based on radio-tracking of four males and two females. This study is the first to investigate social interactions and spatial structure within a paca population in unprotected marginal habitat. We detected extensive home range overlap between males and between sexes. Male-male overlap was less extensive within core areas, while female core ranges were almost entirely occupied by one or more males. On average, pacas used at least six cavities within their home range. The majority of cavities were in the core areas and we did not detect simultaneous co-habitation of the same location. On average, females occupied cavities that were closer together, and closer to water bodies, than those of males. Overall, our study suggests a general tolerance during nocturnal foraging activities, but exclusive use of core areas and associated cavities. The larger ranges of males than females and the extensive overlap between conspecifics suggest a polygamous or promiscuous mating system in this landscape.

Canine distemper viral infection threatens the giant panda population in China.

We evaluated exposure to canine distemper virus (CDV) in eight wild giant pandas (Ailuropoda melanoleuca) and 125 unvaccinated domestic dogs living in and around Foping National Nature Reserve (FNNR), China. Seventy-two percent of unvaccinated domestic dogs (mixed breed) had neutralizing antibodies for CDV due to exposure to the disease. The eight wild giant pandas were naïve to CDV and carried no positive antibody titer. RT-PCR assays for hemagglutinin (H) gene confirmed the presence of CDV in 31 clinically ill dogs from several areas near FNNR. Genomic sequence analysis showed that the 21 canine CDV were highly homologous to each other and belonged to the Asian-1 genotype. They showed high homology with the GP01 strain sequenced from a fatally infected giant panda, suggesting cross-species infection. Observational and GPS tracking data revealed home range overlap in pandas and dogs around FNNR. This study shows that CDV is endemic in domestic dogs near FNNR and that cross-species CDV infection threatens the wild giant panda population.

Genomics meets applied ecology: Characterizing habitat quality for sloths in a tropical agroecosystem

Understanding how habitat quality in heterogeneous landscapes governs the distribution and fitness of individuals is a fundamental aspect of ecology. While mean individual fitness is generally considered a key to assessing habitat quality, a comprehensive understanding of habitat quality in heterogeneous landscapes requires estimates of dispersal rates among habitat types. The increasing accessibility of genomic approaches, combined with field-based demographic methods, provides novel opportunities for incorporating dispersal estimation into assessments of habitat quality. In this study, we integrated genomic kinship approaches with field-based estimates of fitness components and approximate Bayesian computation (ABC) procedures to estimate habitat-specific dispersal rates and characterize habitat quality in two-toed sloths (Choloepus hoffmanni) occurring in a Costa Rican agricultural ecosystem. Field-based observations indicated that birth and survival rates were similar in a sparsely shaded cacao farm and adjacent cattle pasture-forest mosaic. Sloth density was threefold higher in pasture compared with cacao, whereas home range size and overlap were greater in cacao compared with pasture. Dispersal rates were similar between the two habitats, as estimated using ABC procedures applied to the spatial distribution of pairs of related individuals identified using 3,431 single nucleotide polymorphism and 11 microsatellite locus genotypes. Our results indicate that crops produced under a sparse overstorey can, in some cases, constitute lower-quality habitat than pasture-forest mosaics for sloths, perhaps because of differences in food resources or predator communities. Finally, our study demonstrates that integrating field-based demographic approaches with genomic methods can provide a powerful means for characterizing habitat quality for animal populations occurring in heterogeneous landscapes.

White-nosed coatis in Arizona: tropical carnivores in a temperate environment

Intraspecific variation in ranging and social behavior can be perplexing, but also provides an opportunity to assess which behavioral attributes are labile in the face of geographic variation in resources. White-nosed coatis (Nasua narica) are group-living carnivores of tropical origin that possess an unusual social system. In the resource-rich tropics, larger-bodied males are solitary, whereas females live in groups (“bands”) along with young of both sexes, but leave them to give birth and wean their young. Males often disperse socially, but not spatially. We studied coatis in the Chiricahua National Monument, Arizona, a resource-poor, arid, and highly seasonal landscape. Using live capture and radiotelemetry in conjunction with microsatellite DNA analyses, we found that Chiricahua coatis exhibited the species-typical pattern of solitary males and gregarious females. Young males left their natal bands as yearlings, and some were found as adults within their natal home range. On the other hand, home ranges were expanded greatly. Bands, and some males, focused their movements in areas several km² in extent over periods of weeks or months but shifted those areas markedly among seasons. Some males followed the typical mammalian pattern of natal dispersal beyond their natal area. Rates of movement were higher and female associations appeared to be more flexible than in the tropics. Adult females sometimes ranged singly, not only around the time of parturition, but also when population density was low and occasionally otherwise. In addition, home range overlap was high among both sexes during some seasons, and female bands sometimes fused for prolonged periods. Core patterns of sociality are constant in both resource-rich tropical and resource-poor temperate populations, but coatis appear to make major adjustments in scale of movement and frequency of association in response to resource variation.

Space Use and Social Mating System of the Hantavirus Host, Oligoryzomys longicaudatus.

The long-tailed mouse, Oligoryzomys longicaudatus (Cricetidae: Sigmodontinae), is the major host of Andes hantavirus, the etiological agent of hantavirus pulmonary syndrome in the south of Argentina and Chile. Studying the ecology of this species is necessary to understand how Andes hantavirus is maintained in nature. In this study, we examine the home range size and intra- and intersexual overlap degree of male and female O. longicaudatus in order to elucidate the mating system of this species. To our knowledge, this research provides the first documentation, obtained from a specific design, of spacing and mating systems in this species in Argentina. The study was conducted seasonally from April (autumn) 2012 to October (spring) 2013 in a shrubland habitat of Cholila, Andean region, Argentina. We studied spacing patterns using 59 and 51 home ranges established by adult males and females, respectively, in two 3.24ha capture-marked and recapture grids. Significant differences between sexes in home range size and overlap degree were found. Male home ranges were always larger than those of females. We observed exclusive space use both among males and females (13.15±18.67, and 3.60±3.43%, respectively). Considering only those males that get access to receptive females (40%), average intersexual overlap value was about 30.82±19.73%. Sexual differences in home range sizes and the spatial avoidance between breeding males, that would reflect intrasexual competition for receptive females, allows us to propose a polygynous mating system for O. longicaudatus.

Sociospatial structure explains marked variation in brucellosis seroprevalence in an Alpine ibex population

In a context of (re)emerging infectious diseases with wildlife reservoirs, understanding how animal ecology shapes epidemiology is a key issue, particularly in wild ungulates that share pathogens with domestic herbivores and have similar food requirements. For the first time in Europe, brucellosis (Brucella melitensis), a virulent zoonosis, persisted in an Alpine ibex (Capra ibex) population and was transmitted to cattle and humans. To better understand disease dynamics, we investigated the relationships between the spatial ecology of ibex and the epidemiology of brucellosis. Combining home range overlap between 37 GPS-collared individuals and visual observations of 148 visually-marked individuals monitored during the 2013–2016 period, we showed that females were spatially segregated in at least 4 units all year round, whereas males were more prone to move between female units, in particular during the rutting period. In addition to ibex age, the spatial structure in females largely contributed to variation in seroprevalence in the whole population. These results suggest that non-sexual routes are the most likely pathways of intraspecific transmission, crucial information for management. Accounting for wildlife spatial ecology was hence decisive in improving our ability to better understand this health challenge involving a wildlife reservoir.

Use of space in two neighboring groups of the howler monkey Alouatta palliata mexicana (Primates: Atelidae): overlap and home range size

The interaction between primate groups and the dynamics involved in the use of space are important factors affecting both competition for resources and intergroup dominance. In the present study we analyzed the differences in home range overlap and intergroup size, as well as the diversity of tree species within the home range, the Value Index for the key tree species, and the daily activity pattern of two neighboring groups of the howler monkey Alouatta palliata. From March 2002 to June 2003, the behavior and location of two groups of monkeys (G1, two adult males, four adult females and four infants; G2, six adult males, five adult females, one juvenile and three infants) were recorded in the same forest patch at Los Tuxtlas Biosphere Reserve, Veracruz, Mexico. Using the Minimum Convex Polygon (100 %), grid (100 m), and Kernel (adapted and fixed) methods, as well as transect sampling, significant differences (F1, 20 = 14.45, P = 0.001) were found in the home range size of the groups, being greater in G2. The habitat in the G2 home range had greater richness and diversity of tree species, as well as a higher Importance Value Index for the key tree species (Ficus spp.) included in the howler monkey diet. On the other hand, significant differences between groups (Mann-Whitney U = 38, P < 0.05) were found only as regards locomotion behavior, likely due to a behavioral adaptation to optimize food resource use or search. The two groups displayed a similar use of food resources; however, there was a slight overlap in the home range between both groups with no direct aggression, likely because their habitat included sufficient space and food. Our data suggest that the reduced overlap may vary between neighboring groups because of factors such as group size. However, groups could weigh various factors to avoid home-range overlap.

Spatial ecology and habitat use of giraffe (Giraffa camelopardalis) in South Africa

The lack of long-term studies remains a limiting factor in understanding the home range, spatial ecology and movement of giraffes. We equipped eight giraffes with GPS satellite units and VHF capacity, which were built in to the collars for the remote collection of data on their movements and home ranges over two years on Khamab Kalahari Nature Reserve (KKNR) within the Kalahari region of South Africa. Giraffe numbers in KKNR dropped from 135 individuals to 111 in just five years, revealing the lack of knowledge about their required habitat needs, space use and diet. With over 1000km2 available for roaming within the reserve, habitat selection, principle and preferred food species played a significant role in home range size and overlap between individuals. These giraffes used an average annual home range of 206km2 (20602ha) as calculated by a 95% minimum convex polygon (MCP) with a standard deviation core home range calculated by a 50% MCP of 10.1km2 to satisfy their annual needs for survival and reproduction in their preferred vegetation. In the wet, hot season (summer: December–February) when food was abundant, giraffes frequented smaller areas (average 177km2), while in the dry, cool season (winter: June to August) the mean home range size increased to approximately 245km2. Rainfall influenced spatial distribution since it determined vegetation productivity and leaf phenology. The different seasons influenced giraffe movements, while different vegetation types and season influenced their home range size. Season and food availability also influenced home range overlap between different giraffe herds. Home range overlap occurred when giraffes were forced to roam in overlapping areas during the dryer months when the winter deciduous nature of the majority of the tree species resulted in lower food availability. In winter, the overlap was approximately 31% and in autumn approximately 23%. During the wet and warmer months, overlapping was 15% in summer and 19% in spring, respectively. The percentage of time spent in different vegetation type areas was influenced by the abundance of the principal food species of that plant community. It is thus concluded that the movements of giraffes were primarily influenced by a combination of environmental factors such as season, rainfall and vegetation density.

Mule deer spatial association patterns and potential implications for transmission of an epizootic disease.

Animal social behaviour can have important effects on the long-term dynamics of diseases. In particular, preferential spatial relationships between individuals can lead to differences in the rates of disease spread within a population. We examined the concurrent influence of genetic relatedness, sex, age, home range overlap, time of year, and prion disease status on proximal associations of adult Rocky Mountain mule deer (Odocoileus hemionus hemionus) in a chronic wasting disease endemic area. We also quantified the temporal stability of these associations across different sex, age, and disease status classes. We used three years of high frequency telemetry data from 74 individuals to record encounters within 25 m of each other, and to calculate seasonal home range overlap measured by volume of intersection (VI). The strength of pairwise spatial association between adult mule deer was independent of genetic relatedness, age and disease status. Seasonal variation in association strength was not consistent across years, perhaps due to annual changes in weather conditions. The influence of home range overlap on association strength varied seasonally, whereby associations were stronger in pre-rut and fawning than in the rest of the seasons. The sexes of individuals also interacted with both VI and season. At increasing levels of VI, associations were stronger between females than between males and between females and males. The strongest associations in pre-rut were between males, while the strongest in rut were between females and males. The temporal stability of associations was markedly dependant on the sex and the diagnosis of the associating pair. Our findings highlight the importance of considering concurrent effects of biological and environmental factors when seeking to understand the role of social preference in behavioural ecology and disease spread. Applying this knowledge in epidemiological modelling will shed light on the dynamics of disease transmission among mule deer.

Does landscape connectivity shape local and global social network structure in white-tailed deer?

Intraspecific social behavior can be influenced by both intrinsic and extrinsic factors. While much research has focused on how characteristics of individuals influence their roles in social networks, we were interested in the role that landscape structure plays in animal sociality at both individual (local) and population (global) levels. We used female white-tailed deer (Odocoileus virginianus) in Illinois, USA, to investigate the potential effect of landscape on social network structure by weighting the edges of seasonal social networks with association rate (based on proximity inferred from GPS collar data). At the local level, we found that sociality among female deer in neighboring social groups (n = 36) was mainly explained by their home range overlap, with two exceptions: 1) during fawning in an area of mixed forest and grassland, deer whose home ranges had low forest connectivity were more social than expected; and 2) during the rut in an area of intensive agriculture, deer inhabiting home ranges with high amount and connectedness of agriculture were more social than expected. At the global scale, we found that deer populations (n = 7) in areas with highly connected forest-agriculture edge, a high proportion of agriculture, and a low proportion of forest tended to have higher weighted network closeness, although low sample size precluded statistical significance. This result implies that infectious disease could spread faster in deer populations inhabiting such landscapes. Our work advances the general understanding of animal social networks, demonstrating how landscape features can underlie differences in social behavior both within and among wildlife social networks.

Space invaders: effects of invasive alien Pallas’s squirrel on home range and body mass of native red squirrel

Alien species can affect native species through several ecological processes such as competition. Here we tested the hypothesis of interspecific competition for space and food resources between the native Eurasian red squirrel and the invasive Pallas’s squirrel introduced in Italy. We used an experimental study design comparing space and habitat use and body condition parameters of red squirrels between areas of co-occurrence with the Pallas’s squirrel and areas without it. There were no differences in mean home range size of red squirrels between red-only areas and red-Pallas. However, when Pallas’s squirrels were removed, the red squirrels increased their home ranges. Moreover, in the area of syntopy, red squirrels had a higher degree of intraspecific home range overlap than in the red-only area. We also found indirect evidence for competition for food with red squirrels having a poorer body condition when co-occurring with the alien species. We analyzed the body mass and size of red squirrels in the two areas and our results showed that red squirrels had a reduced body mass and size when in syntopy, confirming that the interspecific competition does not allow red squirrels to reach the optimum body condition that they would have if the competitor was not present. Moreover, tree-species niche overlap was very high and both species fed primarily on the same tree seeds. Differences in vegetation cover between areas are discussed. This is the first study that confirms the invasiveness of the Pallas’s squirrel also in terms of capability to compete with native species.

Summer-fall home-range fidelity of female elk in northwestern Colorado: Implications for aspen management

Understanding the degree of spatial fidelity exhibited by individuals within a species increases our ability to manage for desired future outcomes. Elk (Cervus elaphus) is a closely managed species in the Western US, but there is little research evaluating their summer home-range fidelity. Elk summer-fall home-ranges overlap considerably with aspen (Populus tremuloides)-dominated forest types, and elk can impact aspen regeneration because it is a preferred browse species. We evaluated the fidelity of 72 adult female elk to individual summer-fall home ranges in northwestern Colorado, USA, during two consecutive summers (1996 and 1997). To compare elk summer-fall home-range overlap and distribution based on individual kernel-estimated utilization distributions, we calculated the volume-of-intersection statistic and the inter-annual distances between centers-of-mass. We found adult female elk in the White River Study area exhibited strong fidelity to individual home ranges. Volume-of-intersection results indicated that 93% of the elk showed explicit home-range overlap between 1996 and 1997, but that all the elk returned to the same vicinity as the previous year (median=0.42, SE=0.02, n=72). Between-year center-of-mass distances ranged from 183m to 34,170m (mean=3819, SE=619, n=72), while within-year maximum distances between location points ranged from 4320m to 31,680m (mean=13,958, SE=628, n=72). Hunting increased the distance traveled by individual elk, but did not change the center of their home-range. Understanding female elk home-range fidelity could influence forest management focused on aspen regeneration. Specifically, targeted removal of female elk from their summer-fall home ranges could create a ‘window of opportunity’ in which browsing pressure was reduced, and the likelihood of aspen recruitment increased.

Gray fox home range, spatial overlap, mated pair interactions and extra‐territorial forays in southwestern Georgia, USA

Despite numerous studies estimating gray fox Urocyon cinereoargenteus home range sizes, there have been few studies to evaluate more nuanced space use patterns; thus little is known about gray fox spatial ecology beyond estimates of home range size. We used GPS‐technology to track 34 gray foxes (20 males and 14 females) from February 2014 until December 2015 in southwestern Georgia, USA. Home range sizes were similar among seasons (p &gt; 0.05), but core area sizes were smaller during spring than during winter and summer (p &lt; 0.05). As would be expected, home range overlap was much greater between mated pairs than among neighboring animals and core area overlap among neighbors did not occur. Members of a mated pair apparently interacted frequently, with 29.4% of all simultaneous locations occurring within 40 m of each other. Members of mated pairs interacted more diurnally during spring (49.9%) which is concurrent with denning, than during summer (31.5%), while nocturnal interactions were similar during spring (18.0%) and summer (19.3%). We recorded 25 extra‐territorial forays from 10 of 26 gray foxes. Three male foxes were responsible for nearly half (12) of these forays. Because these forays took place during the breeding season, we suggest males may have been seeking extra‐pair copulations.

Breeding Season Space Use and Habitat Selection of Adult Female Scaled and Gambel's Quail in West Texas

We used radiotelemetry to investigate breeding-season (1 Apr–1 Sep, 2012 and 2013) home ranges and habitat selection of adult female scaled (Callipepla squamata) and Gambel’s quail (C. gambelii) in the eastern Chihuahuan Desert, Texas. Mean breeding-season home range (95% fixed kernel) for scaled quail was 145.02 ± 23.56 ha (range = 22.03–538.24 ha) and 156.32 ± 13.04 ha (range = 66.15– 270.74 ha) for Gambel’s quail. Mean core-use area (50% fixed kernel) for scaled quail was 31.38 ± 4.80 ha (range = 4.03–111.36 ha) and 32.87 ± 2.61 ha (range = 12.19–52.36 ha) for Gambel’s quail. We found evidence of home-range overlap in neighboring females in both species. Excessive drought can suppress nesting activity. However, encourage reproductive activity in both species may be encouraged by managing riparian areas to provide adequate forage and microclimatic conditions.

Genetic relatedness affects socio-spatial organization in a solitary carnivore, the European pine marten

Genetic relatedness among individuals can play a major role in the socio-spatial organization of mammals. However, only a few studies have documented kin-related spatial pattern in solitary medium-sized carnivores. Using radiotelemetry and genetic data from 15 individuals (seven males and eight females), we investigated the relationship between kinship and spatial organization (distance and overlap between home ranges) in the European pine marten Martes martes in a wooded area of central Italy. Data analysis included 45 pairs (10 individuals) tracked in spring and summer and 66 pairs (12 individuals) tracked in autumn and winter. Kinship, distance between home ranges and proportion of home range overlap were also compared among inter- and intra-sexual pairs. Spatial distribution of pine martens was affected by genetic relatedness, so that individuals living in close proximity or occupying the same area were also more likely to be closely related. Female pairs had a higher proportion of overlap of their home and core ranges than male pairs. Male pairs were also less related than female and inter-sexual pairs, showing a pattern of space use consistent with male-biased dispersal and female philopatry. Most of the females that overlapped their home and core ranges were genetically related, while only a third of the few male pairs occupying the same territories were kin. However, our results seem to indicate that positive association between home range overlap and relatedness was mainly a consequence of common female philopatry rather than kin-biased tolerance. Male-female dyads had the highest percentage of related individuals overlapping their home and core ranges, suggesting that spatial segregation is unlikely to play a role in preventing encounters between kin.

Spatial ecology of jaguars, pumas, and ocelots: a review of the state of knowledge

AbstractKnowledge of the spatial ecology of mammalian carnivores is critical for understanding species’ biology and designing effective conservation and management interventions. We reviewed the available information about the spatial ecology of jaguarsPanthera onca, pumasPuma concolor, and ocelotsLeopardus pardalis,and we examined how sex and extrinsic variables affect their spatial behaviour.Sixty‐one articles addressing home range, home range overlap, daily net displacement (straight‐line distance between two locations on consecutive days), and/or distance of dispersal of the three species were included. Meta‐analysis,ANOVA,ANCOVA, and beta regression tests were run to analyse differences among species and sexes and to elucidate the influence of other variables, such as latitude and ecoregion, on spatial behaviour.Pumas had on average larger home ranges (mean ± SE: 281.87 ± 35.76 km2) than jaguars (128.61 ± 49.5 km2) and ocelots (12.46 ± 3.39 km2). Intersexual range overlap was higher than intrasexual range overlap in jaguars and pumas. Sex affected the home range size of all three species, but only influenced daily net displacement in ocelots. Ecoregion affected the home range size of all three species but did not significantly affect either the daily net displacement or the dispersal distance of pumas. Latitude affected the home range size of jaguars and pumas. It did not affect daily net displacement or dispersal distance in jaguars and pumas, but did affect daily net displacement in ocelots.Although there was a lack of studies in most countries for the three species, information was particularly lacking in the Neotropics for jaguars and pumas and in North America for ocelots. Researchers usually presented low sample sizes and used different methods to examine the ecological issues considered here. Homogenisation of methods is needed to clarify the ecology of these species and to allow a better understanding of the threats to their populations.

Spatial behaviour and food choice of the Garden Warbler Sylvia borin during the non-breeding season

Information regarding the spatial behaviour of migratory bird species on their wintering ground is important in understanding the factors that can influence breeding success and population size. The Garden Warbler Sylvia borin is a migratory species that has been well studied in West Africa. However, information regarding its spatial behaviour during the non-breeding season in sub-Saharan Africa is still limited. Consequently, we investigated the 50% and 95% kernel density home-range size and overlap as well as food choice of 10 radio-tracked Garden Warblers at Amurum, central Nigeria and Obudu, south-eastern Nigeria. Home-range overlap was estimated using the kernelUD function within the package adehabitat in R. The mean home-range was 7.0 ha and 3.3 ha at Amurum and Obudu, respectively, whereas the core of the home-range was on average 1.5 ha and 0.7 ha, respectively. Mean home-ranges were larger than the average territory of individuals on the temperate breeding grounds. Home-range overlap ranged between 19% and 57% at Amurum and 39% and 71% at Obudu, suggesting that Garden Warblers are not territorial during the non-breeding season in Nigeria. The diet of the Garden Warblers at both sites comprised of berries and insects and several individuals were often observed foraging together.

Spatiotemporal requirements of the Hainan gibbon: Does home range constrain recovery of the world's rarest ape?

Re-evaluation reveals Hainan gibbon home range as c. 1-2 km2 . Hainan gibbon home range is, therefore, similar to other Nomascus gibbons. Limited data for extremely rare species does not necessarily prevent derivation of robust home range estimates.