Land use patterns within Wattled Crane (Bugeranus carunculatus) home ranges in an agricultural landscape in KwaZulu-Natal,South Africa

There The Wattled Crane Bugeranus carunculatus is one of the top five most threatened bird species in South Africa, with the main threat being the loss of undisturbed breeding habitat. A basic understanding of this species' use of its environment is needed to implement conservation action. This quantitative study focused on determining the home range size of active breeding pairs in the KwaZulu-Natal midlands of South Africa, and assessing the land use composition of these home ranges. Wattled Cranes were found to have an average home range size of 16.64km², consisting mostly of open natural grassland (mean of 75.5% of the overall home range of pairs). Other significant land use contributions to the home ranges were temporary irrigated and dryland cultivated agriculture. The core breeding area (wetland) of the home range constituted only 2.3% of the overall home range size, consisting of similar proportions of both wetland (48.9%) and grassland (51.8%) habitat. This indicates the dependence of Wattled Cranes on specific wetland habitats, surrounded by natural grassland. Wattled Cranes show home range sizes larger than other similar-sized crane species, suggesting that this may be as a result of their large body size and their occupation of highly transformed and fragmented habitats in an agricultural landscape. However, the occurrence of transformed land use types in home ranges suggests that breeding pairs tolerate some degree of disturbance within their home ranges. The home ranges do not appear to be currently restricted by surrounding land use types, indicating that factors other than habitat loss may be contributing to breeding site losses. The study has therefore indicated the need for closer working relationships between conservationists and agricultural communities to promote the conservation of valuable natural grasslands surrounding wetlands.     

Site fidelity and home range variation during the breeding season of peregrine falcons (Falco peregrinus) in Yamal,Russia

Many different ecological factors affecting the size, use, and spatial configuration of home ranges have been investigated, yet the chronology of the breeding cycle has been relatively under studied. Here, we studied peregrine falcons (Falco peregrinus) to describe variation in home range within and between breeding seasons in the Yamal peninsula, a region of the Russian Arctic with a high breeding density of peregrines. We used satellite telemetry to investigate variation in home range at different stages of the breeding cycle during three breeding seasons (2009–2011). We fitted Argos satellite transmitters to 10 breeding peregrines (nine females and one male) and two male fledglings. All breeding females showed fidelity to the region of the southwestern Yamal peninsula, but they were not necessarily faithful to their specific breeding ranges with 33 % dispersing to new ranges up to 40 km away. The population of peregrines in our study area was relatively synchronous in their breeding chronology, with clutches initiated in close synchrony in early June despite the birds arriving on their breeding ranges ca. 3 weeks earlier. The average home range size for breeding females was 98 km² (95 % Maximum Convex Polygon). Over the breeding season, the home range area utilized by females increased in the late nestling period and again after the chicks fledged. Expansion of the home range coincided with changes in behavior associated with parental care, resulting in greater activity and more time spent away from the nest area when the female began hunting to provision nestlings and fledglings.     

Home range and habitat use by the sable<Emphasis Type="Italic"> Martes zibellina brachyura</Emphasis> in a Japanese cool-temperate mixed forest

Home range and habitat use of the sable Martes zibellina brachyura were studied in a cool-temperate mixed forest in northernmost Japan. In both sexes, some sables showed a wide range of migration without establishing home ranges and the others had home ranges of 0.50–1.78 km² (mean: 1.12±SD 0.495 km², n =6) which were not significantly correlated with body weight or age. The analysis of canine tooth annuli revealed that the maximum age was 5.5 years. The home ranges of some sables overlapped so extensively that the home ranges and even the core areas did not appear exclusive to other sables. We determined resting sites and foraging routes in snow in winter. Comparison of vegetation at the resting sites and foraging routes with habitat availability suggested that the sables preferred resting in dense-tree forests with many tree species and debris probably in order to avoid predators (red foxes) and strong wind and foraging in forests of climax succession which are usually rich in their prey such as voles and mice.     

Insights into post-fledging dispersal of Bearded Vultures Gypaetus barbatus in southern Africa from GPS satellite telemetry

Capsule: Fledglings progressively increase their home range size and ranging behaviour as they age.

Aims: To examine the home range size and ranging behaviour of Bearded Vulture fledglings during the post-fledging dependence period and determine the onset of natal dispersal.

Methods: Post-fledging movements of three individuals were investigated in southern Africa using global positioning system (GPS) satellite telemetry which enabled home range sizes and distances travelled from the nest to be calculated.

Results: Fledglings increased their home range size from an average of 0.4–10 999?km² (100% Minimum Convex Polygons) and 9.13–11 466?km² (fixed 95% kernels) within the first six months post fledging. They also increased home range use as they aged with maximum daily distances travelled from the nest occurring between 98 and 136 days post fledging (when fledglings were aged between 222 and 262 days), after which time they dispersed from their natal area. Distances between fixes were highest during the dispersal period.

Conclusion: GPS satellite telemetry allows us to accurately demonstrate how fledglings progressively increase and use their home ranges as they age and undertake pre-dispersive exploratory flights. Results confirm the notion that juveniles disperse at the onset of the following breeding season and suggest that dispersal occurs earlier in the southern hemisphere.     

Status and structure of the griffon vulture (Gyps fulvus) population in Crete

Griffon vulture (Gyps fulvus) population surveys were conducted during 1996–2002 in the island of Crete (Greece) to document population status and structure. Fieldwork was carried out during the breeding period when birds could be monitored in their colonies. Total population size was estimated at 379 individuals (range = 341–417) with adult birds comprising 63%. The breeding population was estimated at 141 pairs, which were distributed on an average in 23 colonies per year (range = 16–30) while the mean number of breeding pairs that laid eggs was 98 (range= 64–126). Crete thus supports the largest insular population of the species in the world and hosts 70–80% of the breeding population of the species in Greece. Population density was estimated at 6.9 individuals/100 km², 2.6 breeding pairs/100 km² and 1.8 nesting pairs/100 km². The average home range of an occupied colony (i.e., breeding group) was estimated at ca. 204 km² producing a theoretical foraging range of 8 km radius around the breeding cliff. No trends in the total number of individuals and breeding pairs appeared to exist, although significant differences in population size of individual colonies occurred between the years. The majority of the population was concentrated in small-sized colonies, which showed a low occupancy rate. The number of abandoned sites and the colonization of new ones could represent a shift of breeding pairs to alternative colonies provoked by local food abundance and conspesific attraction.     

Big Cats in the Big City: Spatial Ecology of Mountain Lions in Greater Los Angeles

Large carnivores can represent the ultimate challenge for conservation in developed landscapes because of their large area requirements and potential for conflict with humans. Some large carnivores such as mountain lions (Puma concolor) can use a wide range of biomes and vegetation types, and in southern California, USA, they persist in metropolitan Los Angeles, a megacity of 18 million people. Understanding how large carnivores use highly altered landscapes is important for their conservation and management. We estimated home range size, landscape use, and landscape selection for mountain lions in the Santa Monica Mountains and surrounding areas for 29 subadult and adult animals from 2002 to 2016, using 128,133 locations from global positioning system (GPS)-collars. Home range size was similar to that reported by other researchers; home ranges averaged 372 km² for adult males and 134 km² for adult females, except for 2 adult males in isolated habitat fragments that maintained 2 of the smallest adult male home ranges ever recorded (24 km² and 54 km²). Mountain lions very rarely entered developed areas, consistently avoided altered open areas such as golf courses, cemeteries, or other landscaped spaces, and showed a positive relationship between home range size and amount of development, all indicating that developed areas have reduced value for mountain lions. Mountain lions from all sex and age classes selected areas closer to development than expected by chance, which could be related to the presence of mule deer (Odocoileus hemionus) or other prey in or adjacent to urbanization. For 2 adult males that occupied home ranges within the most urban portions of our study area, their response to urban development differed strongly across diurnal periods, ranging from avoidance during the day to selection at night. Shrub vegetation types, especially chaparral, were important in terms of habitat use and resource selection, highlighting their importance for conservation of the species in southern California. North America's largest felid can thrive in shrublands and persist even in one of the world's largest cities, although they only very rarely venture into developed areas within that city. © 2021 The Wildlife Society.     

Space use and site fidelity of wintering whooping cranes on the Texas Gulf Coast

The Aransas-Wood Buffalo population (the only non-reintroduced, migratory population) of endangered whooping cranes (Grus americana) overwinters along the Texas Gulf Coast, USA. Understanding whooping crane space use on the wintering grounds reveals essential aspects of this species' ecology, which subsequently assists with conservation. Using global positioning system telemetry data from marked whooping cranes during 2009–2017, we fit continuous-time stochastic process models to describe movement and home range using autocorrelated kernel density estimation (AKDE) and explored variation in home range size in relation to age, sex, reproductive status, and drought conditions. We used the Bhattacharyya coefficient of overlap and distance between home range centroids to quantify site fidelity. We examined the effects of time between winter home ranges and the sex of the crane on site fidelity using Bayesian mixed-effects beta regression. Winter whooping crane 95% AKDE home range size averaged 30.1 ± 45.2 (SD) km² (median = 14.3, range = 1.1–308.6). Home ranges of sub-adult females were approximately 2 times larger than those of sub-adult males or families. As drought worsened, home ranges typically expanded. Between consecutive years, the home ranges of an adult crane exhibited 68 ± 31% overlap (site fidelity), but fidelity to winter sites declined in subsequent winters. The overlap of adult home ranges with the nearest unrelated family averaged 33 ± 28%. As a whooping crane aged, overlap with its winter home range as a juvenile declined, regardless of sex. By 4 years of age, a whooping crane had approximately 14 ± 28% overlap with its juvenile winter home range. Limited evidence suggested male whooping cranes return to within 2 km of their juvenile home range by their fifth winter. Previous data obtained from aerial surveys led ecologists to assume that whooping crane families normally used small areas (~2 km²) and expressed persistent site fidelity. Our analyses showed <8% of families had home ranges ≤2 km², with the average area 15 times greater, and waning site fidelity over time. Our work represents an analysis of whooping crane home ranges for this population, identifying past misconceptions of winter space use and resulting in better estimates of space requirements for future conservation efforts.     

BIODIVERSITY RESEARCH: Fidelity to foraging sites,consistency of migration routes and habitat modulation of home range by sea turtles

Aim Resources can shape patterns of habitat utilization. Recently a broad foraging dichotomy between oceanic and coastal sites has been revealed for loggerhead sea turtles (Caretta caretta). Since oceanic and coastal foraging sites differ in prey availability, we might expect a gross difference in home‐range size across these habitats. We tested this hypothesis by equipping nine adult male loggerhead sea turtles with GPS tracking devices. Location National Marine Park of Zakynthos (NMPZ) Greece, central and eastern Mediterranean (Adriatic, Ionian and Aegean seas). Methods In 2007, 2008 and 2009, Fastloc GPS‐Argos transmitters were attached to nine male loggerheads. In addition, a Sirtrack PTT unit was attached to one male in 2007. Four of the turtles were tracked on successive years. We filtered the GPS data to ensure comparable data volumes. Route consistency between breeding and foraging sites of the four re‐tracked turtles was conducted. Foraging site home range areas and within site movement patterns were investigated by the fixed kernel density method. Results Foraging home range size ranged between circa 10 km² at neritic habitats (coastal and open‐sea on the continental shelf) to circa 1000 km² at oceanic sites (using 90% kernel estimates), the latter most probably reflecting sparsely distributed oceanic prey. Across different years individuals did not follow exactly the same migration routes, but did show fidelity to their previous foraging sites, whether oceanic or neritic, with accurate homing in the final stages of migration. Main conclusions The broad distribution and diverse life‐history strategies of this population could complicate the identification of priority marine protected areas beyond the core breeding site.     

Pattern of space use by female black bears in the White River National Wildlife Refuge,Arkansas, USA

The manner in which space is used by animals may influence several aspects of biology, including the pattern of resource use and intra-specific competition. We monitored 16 radio-collared female black bears (Ursus americanus) for 9,216 radio days during 1993–1995 in the White River National Wildlife Refuge (WRNWR), Arkansas, U.S.A. to investigate space use patterns. Annual home ranges (95% convex polygon) ranged from 2.10 to 11.34 km² with a mean (± SD) size of 4.90 (± 2.09) km² (n = 16). Largest home ranges were occupied by 2 females with yearlings during one year of study. Home ranges among neighbouring bears overlapped considerably. Although bears maintained larger home ranges during summer, the size of home range did not differ among seasons (P > 0.50). Our estimates of home range size for female black bears were smaller than those obtained in a study of the same population during 1979–1982. Because the size of the bear population at WRNWR was substantially smaller (about 130 bears) during 1979–1982 compared to the present population of ≥348 bears, these results suggested that population density and size of female black bear home ranges may be negatively correlated. Conservation implications of density-dependent space use pattern are also discussed.     

野放普氏野马(Equus przewalskii)家域面积及其影响因素

采用MCP方法研究了2011年至2012年新疆卡拉麦里山有蹄类自然保护区野放普氏野马家域的变化。通过方差分析验证了年间、季节间不同群体家域及其两两重叠无差异。以家族群大小为协变量进行了野放野马家域协方差分析。利用野放野马家族大小为协变量的协方差分析分析检验了野放野马家族大小与家域关系。结果表明:(1)野马平均家域面积由2011年的(20±2)km~2/匹扩大到2012年的(30±2)km~2/匹。对部分野放群体中头马未发生更替的野马群的研究表明,随着野马群体增大,其家域面积显著增大(P0.05)。(2)单因素方差分析显示,不同野马群的家域面积在不同年份差异显著,且春季家域秋季家域夏季家域。(3)2011年不同群家域两两间相互重叠面积与群大小无显著相关(r=0.256,P=0.5800.05)。而2012年野马群家域两两之间重叠面积有显著差异(F=4.521,df=8,P0.001)。家域两两相互重叠面积与群大小显著相关(r=0.706,P=0.0330.05)。(4)不同季节间野马群家域重叠面积有显著差异(F=5.695,df=8,P0.001)。5号群、7号群和8号群的自身家域重叠面积(P0.05),3号群、6号群和9号群的家域重叠面积(P0.05)。(5)影响野放野马家域面积的生物因子有草本盖度、灌木盖度,非生物因子主要有温度、湿度、风速、最近水源地距离和最近居民点距离等。温度与草本盖度是影响野放野马家域面积大小的主要因素,两者与野放野马家域面积显著相关(P0.01)。     

The ecology of the introduced patas monkey (Erythrocebus patas) population of Southwestern Puerto Rico

This paper presents the results of a study on the introduced, free-ranging patas monkey population of Southwestern Puerto Rico (SWPR). It describes information on the population size, social group composition, diet, daily ranging patterns, and patas home range during a 3 year period. The patas monkey population in the study area consisted of approximately 120 individuals in four heterosexual groups and several all-male bands. Within their home ranges (26.8 km²), the population density was 4.47 individuals/km². Home range size among the population's four heterosexual groups varied from 3.72 km² to 15.39 km², and minimum daily distance traveled ranged from 0.8–2.0 km. In general, the social structure and mating system of this population parallels what has been described for African populations. However, habitat use, ranging behavior, and the quality of intergroup interactions suggests that patas of this population exhibit territorial behavior. Am. J. Primatol. 45:351–365, 1998. © 1998 Wiley-Liss, Inc.     

Multi Year Observations Reveal Variability in Residence of a Tropical Demersal Fish,Lethrinus nebulosus: Implications for Spatial Management

Off the Ningaloo coast of North West Western Australia, Spangled Emperor Lethrinus nebulosus are among the most highly targeted recreational fish species. The Ningaloo Reef Marine Park comprises an area of 4,566 km² of which 34% is protected from fishing by 18 no-take sanctuary zones ranging in size from 0.08–44.8 km². To better understand Spangled Emperor movements and the adequacy of sanctuary zones within the Ningaloo Reef Marine Park for this species, 84 Spangled Emperor of a broad spectrum of maturity and sex were tagged using internal acoustic tags in a range of lagoon and reef slope habitats both inside and adjacent to the Mangrove Bay Sanctuary zone. Kernel Utilisation Distribution (KUD) was calculated for 39 resident individuals that were detected for more than 30 days. There was no relationship with fish size and movement or site fidelity. Average home range (95% KUD) for residents was 8.5±0.5 km² compared to average sanctuary zone size of 30 km². Calculated home range was stable over time resulting in resident animals tagged inside the sanctuary zone spending ∼80% of time within the sanctuary boundaries. The number of fish remaining within the array of receivers declined steadily over time and after one year more than 60% of tagged fish had moved outside the sanctuary zone and also beyond the 28 km² array of receivers. Long term monitoring identified the importance of shifting home range and was essential for understanding overall residency within protected areas and also for identifying spawning related movements. This study indicates that despite exhibiting stable and small home ranges over periods of one to two years, more than half the population of spangled emperor move at scales greater than average sanctuary size within the Ningaloo Reef Marine Park.     

Home ranges of brown bears on the Kamchatka peninsula and Sakhalin Island

Territorial activity was studied using satellite tracking of four brown bears (Ursus arctos) in Kamchatka in 2005–2006 and three brown bears on Sakhalin in 2011–2012. The size of annual home ranges was 6.09–27.58 km² for females and 153.12 km² for males. The size of the nuclear zone of the annual home ranges did not exceed 1.68 km². Seasonal home ranges were largest in August-September and smallest in May. The home ranges of two females in Kamchatka were significantly overlapped, the lesser degree of overlap was noted for two females on Sakhalin. The nature of the use of the study area by bears, essentially depends on the seasonal distribution of food, in particular salmon.     

Identifying key habitats for the conservation of Bonelli's Eagle Aquila fasciata using radiotracking

Identifying the priority habitats of endangered species is crucial to implementing effective conservation actions. We characterize the key habitats used by Bonelli's Eagle Aquila fasciata, an umbrella and flagship species that is endangered in Mediterranean countries. We radiotracked 17 breeding individuals (10 males and seven females) in Catalonia (NE Iberian Peninsula) and used compositional analysis to determine the key habitats in home‐ranges of both sexes. The main habitats identified within the home‐range area were scrubland, coniferous forests, cropland, sclerophyllous forests, rock outcrops and urban areas, with little difference in habitat use between the sexes. Bonelli's Eagles preferred rocky habitats as breeding areas and scrubland as foraging areas, as these hold the highest abundance of their main prey, Rabbits Oryctolagus cuniculus and Red‐legged Partridges Alectoris rufa. Habitat selection varied seasonally in foraging areas: scrubland was the most preferred habitat type during the breeding season, whereas rocky areas were preferred during the non‐breeding season (although scrubland was also highly selected). Urban areas were avoided both as breeding and as foraging areas. Home‐range size was inversely correlated with the proportion of scrubland, suggesting that this is a key habitat for Bonelli's Eagle. To conserve this species effectively, policies that ensure the preservation of the cliffs used as breeding sites, as well as suitable management of the scrubland used for foraging, should be implemented in the areas inhabited by this species. The promotion of traditional land uses and management techniques that will enhance open areas in Mediterranean landscapes should in the future play an essential role in the conservation of Bonelli's Eagle in Mediterranean habitats.     

Seasonal movements of Gyrfalcons Falco rusticolus include extensive periods at sea

Little information exists on the movements of Gyrfalcons Falco rusticolus outside the breeding season, particularly amongst High Arctic populations, with almost all current knowledge based on Low Arctic populations. This study is the first to provide data on summer and winter ranges and migration distances. We highlight a behaviour previously unknown in Gyrfalcons, in which birds winter on sea ice far from land. During 2000–2004, data were collected from 48 Gyrfalcons tagged with satellite transmitters in three parts of Greenland: Thule (northwest), Kangerlussuaq (central‐west) and Scoresbysund (central‐east). Breeding home‐range size for seven adult females varied from 140 to 1197 km² and was 489 and 503 km² for two adult males. Complete outward migrations from breeding to wintering areas were recorded for three individuals: an adult male which travelled 3137 km over a 38‐day period (83 km/day) from northern Ellesmere Island to southern Greenland, an adult female which travelled 4234 km from Thule to southern Greenland (via eastern Canada) over an 83‐day period (51 km/day), and an adult female which travelled 391 km from Kangerlussuaq to southern Greenland over a 13‐day period (30 km/day). Significant differences were found in winter home‐range size between Falcons tagged on the west coast (383–6657 km²) and east coast (26 810–63 647 km²). Several Falcons had no obvious winter home‐ranges and travelled continually during the non‐breeding period, at times spending up to 40 consecutive days at sea, presumably resting on icebergs and feeding on seabirds. During the winter, one juvenile female travelled over 4548 km over an approximately 200‐day period, spending over half that time over the ocean between Greenland and Iceland. These are some of the largest winter home‐ranges ever documented in raptors and provide the first documentation of the long‐term use of pelagic habitats by any falcon. In general, return migrations were faster than outward ones. This study highlights the importance of sea ice and fjord regions in southwest Greenland as winter habitat for Gyrfalcons, and provides the first detailed insights into the complex and highly variable movement patterns of the species.     

Long-Term Habitat Use by Mountain Gorillas (Gorilla gorilla beringei). 1. Consistency, Variation, and Home Range Size and Stability

Mountain gorillas are highly folivorous. Food is abundant and perennially available in much of their habitat. Still, limited research has shown that single gorilla groups heavily used areas where food biomass and quality were relatively high and where they met daily nutritional needs with relatively low foraging effort. Also, ecological factors influenced solitary males less than groups with females. Long-term data on habitat use by multiple mountain gorilla social units and more extensive data on variation in food distribution, presented here, confirm that food distribution influences areal occupation densities across groups and over time. These data also confirm the group/solitary male distinction and show that food distribution became more important for one male once he acquired females. Groups used 25 km ² , and inter-annual home range and core area overlap was often low. Annual home range and core area size varied considerably within groups and across years. It bore no simple relationship to group size and estimated group biomass. Core areas were biased samples of total home ranges and were relatively good foraging areas. One group abruptly shifted its home range in response to male mating competition. Home ranges of two others expanded from 1981 to 1987, though at a decreasing rate. Data on one such group, which varied considerably in size, are consistent with arguments that costs of scramble competition are low except in unusually large groups. Low site fidelity, low scramble costs, and high home range overlap should decrease the ecological costs of female transfer.     

Space use and territoriality of wolverines (<Emphasis Type="Italic">Gulo gulo</Emphasis>) in northern Scandinavia

Space use and territoriality influence population structure and dynamics and is therefore an important aspect in understanding the ecology of animals. We investigated spatial and temporal space use of wolverines (Gulo gulo) in northern Scandinavia. We estimated home ranges of 24 radio-marked individuals (17 females and seven males). Male home ranges (mean 669 km²; SE = 211) were significantly larger than female home ranges (mean 170 km²; Wilcoxon–Mann–Whitney; P = 0.001) and encompassed or included parts of up to five different females. Home range sizes of reproducing (170 km²; SE = 51) and barren (171 km²; SE = 63) adult females did not differ. Wolverines in Scandinavia exhibit intrasexual territoriality, with male home ranges totally exclusive and female home ranges either exclusive or with little home range overlap. Overlap between wolverine territories is most likely explained by intrasexual tolerance and kinship.     

Spacing behaviour and habitat use of rock ptarmigan (Lagopus mutus) at low density in the Italian Alps

Studies of rock ptarmigan Lagopus mutus in northern latitudes have shown that, in the breeding season, the majority of cocks pair monogamously and defend small territories, whilst in most populations, a small proportion of cocks are polygynous or remain unmated. Little is known, however, on spacing behaviour and habitat use of alpine rock ptarmigan populations occurring at low densities at the southern edge of the species’ range. From 1995 to 1997, we trapped, radio-tracked and observed birds in the Central Italian Alps (elevation 2,000–3,000 m) in order to investigate spacing behaviour and habitat use in alpine landscapes where habitats offering rich food and cover are patchy. Both sexes were selective in their habitat use, and cocks did not establish territories on bare ground, artificial or nutrient rich grasslands or bogs. In the breeding season, cocks had larger home ranges than hens (cocks 99 ± 57 ha, hens 50 ± 25 ha) that overlapped with the ranges of neighbouring cocks and hens. Cocks were monogamous and defended relatively large territories (core areas of home ranges: cocks 37 ± 26 ha, hens 24 ± 12 ha), which corresponded with low spring densities (0.47–2.29 cocks km⁻² and 0.35–1.60 pairs km⁻²). Territory size of individual cocks was negatively correlated with the amount of high quality habitat in the core-area. Our results suggest increased home ranges and large breeding territories in low density alpine rock ptarmigan populations, compared to populations occurring at higher densities in the central and northern alps, and on subarctic and arctic grounds at northern latitudes, confirming the predictions of models on food-based territoriality.     

Seasonal home ranges and fidelity to breeding sites among ringed seals

Population structure and patterns of habitat use among ringed seals (Phoca hispida) are poorly known, in part because seasonal movements have not been adequately documented. We monitored the movements of 98 ringed seals in the Beaufort and Chukchi seas between 1990 and 2006 using three forms of telemetry. In the winter—spring period (when the seals were occupying shorefast ice), we used radio and ultra-sonic tags to track movements above and below the ice, respectively. We used satellite-linked transmitters in summer and fall (when the seals ranged away from their winter sites) to track at-sea movements. In the shorefast ice habitat, the home ranges of 27 adult males ranged from <1 to 13.9 km² (median = 0.628) while the home ranges of 28 adult females ranged from <1 to 27.9 km² (median = 0.652). The 3-dimensional volumes used by 9 seals tracked acoustically under the ice averaged 0.07 (SD = 0.04) km³ for subadults and adult males and 0.13 (SD = 0.04) km³ for adult females. Three of the radio-tracked seals and 9 tracked by satellite ranged up to 1,800 km from their winter/spring home ranges in summer but returned to the same small (1–2 km²) sites during the ice-bound months in the following year. The restricted movements of ringed seals during the ice-bound season—including the breeding season—limits their foraging activities for most of the year and may minimize gene flow within the species.     

Reproductive and age classes do not change spatial dynamics of foraging long-fingered bats (Myotis capaccinii)

Spatial dynamics of foraging long-fingered bats (Myotis capaccinii) were studied in the Eastern Iberian Peninsula. We analysed the locations of 45 radio-tracked individuals during three discrete periods through the breeding season and measured the spatial parameters related to their foraging behaviour in order to test whether variations in spatial use occur. Colony range, measured as the minimum convex polygon through all the radiolocations, was 345 km², but the area used during each period was smaller. During pre-breeding, foraging bats gathered at two stretches of different tributary rivers; during lactation, they scattered throughout the river system; and during weaning, they aggregated at a stretch of the main river. Individuals on average flew 5.7 km from roosts to foraging areas, with a maximum absolute distance of 22.7 km. Individual foraging ranges were measured linearly, because the bats foraged mostly along rivers; their values averaged 1.3 km/night and overlapped extensively between neighbouring bats (>65% on average). The sampling period, rather than the bats’ reproductive status, age, or sex, explained the observed variability in spatial distribution and size of hunting sites. We did not find differences in spatial parameters between lactating females and non-lactating bats, nor between juveniles and adults. This is the first study to split the independent effects of season and population class in order to enable unconfounded interpretations of the spatial dynamics of foraging reproductive females and juveniles. We speculate that the relationship between colony size and prey availability ruled the observed changes in foraging area through seasons. The considerable overlap in individual foraging ranges may be a necessary adaption to large colonies forced by the specific roost requirements of the long-fingered bat and the narrow foraging niche they appear to occupy.