Habitat use and behaviour of European hedgehogErinaceus europaeus in a Danish rural area

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

Influence of population density and reproduction on space use and spatial relations in the edible dormouse

Food resources and population density are key factors influencing spatiosocial organisation. We compared the space use of two dormiceGlis glis (Linnaeus, 1766) populations differing in density, one high and the other low, in a breeding year 2002 (when trees masted) and in a non-breeding year 2001 (with reproductive failure and a total lack of mast). In the low-density population males always had larger home ranges and travelled longer distances than females. In the high-density population such differences between sexes became significant only in the breeding year. Home ranges and distances travelled each night were larger in the low-density population, but only for males.     

Spatial and temporal habitat use of kob antelopes (Kobus kob kob, Erxleben 1777) in the Comoé National Park, Ivory Coast as revealed by radio tracking

Spatial and temporal habitat use of kob antelopes (Kobus kob kob) have been investigated in the Comoé National Park (Ivory Coast, West Africa) by use of radio telemetry. A total of 23 kob were equipped with radio collars and radio tracked for up to 15 months. Home ranges of males were smaller and those of females larger than expected from theoretical models. Adult males used smaller areas than adult females and did not show seasonal home range shifts. Daily distances travelled did not differ between sexes. Kob walked less during the night than by day and covered shorter distances in the wet season. Whereas an increase in home range overlap between females resulted in higher rates of association among individuals, association of adults of mixed sexes was not correlated with the degree of home range overlap. Territorial behaviour of males and predator avoidance by females are suggested to explain the sex‐specific differences in home range size of adults and the deviation from the predicted sizes. Predator avoidance is presumed as the main reason for the reduced walking distances at night as well as in the wet season. Reproductive behaviour and feeding ecology are assumed to determine the degree of association of conspecifics.     

Ranging and nesting behaviour of the dormouse Muscardinus avellanarius, in coppice-with-standards woodland

Radiotracking was used to investigate the movements of dormice at different times during the summer, in an area of coppice-with-standards woodland, a habitat traditionally associated with this species. The dormice were shown to be wholly arboreal in their activity, foraging in different strata of their three-dimensional habitat, as different food sources became seasonally available. Nest sites were located and both sexes were found to travel only short distances from them, implying that this species probably has a low potential for dispersal. Males normally travelled further than females each night and had larger home ranges, within which activity was usually concentrated in small areas associated with a particular food resource. The findings are discussed in relation to woodland management and distribution surveys.     

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.     

Home range and habitat use by the serotine bat, Eptesicus serotinus, in England

Serotine nursery roosts with less than 20 bats were found to have home ranges of at least 24 to 77 km² and core areas of activity from 13 to 33 km². The size of the range may have increased further if more individuals had been tracked, as three of the four colonies studied had not reached their asymptotes. The total home-range area covered by four serotine colonies was 127.36 km². Excluding non-breeding bats, a density of one bat per 120 ha was estimated. However, actual density was likely to be higher if there were additional non-breeding females and immatures that were not in nursery roosts. Colonial home ranges and core areas overlapped, with individuals from different colonies feeding at the same sites. Individual home ranges ( n = 32) varied from 0.16 to 47.58 km², but these were not used exclusively by one individual. Around the colonial core area and breeding roosts, home ranges were used by all individuals from a single colony. It is only further from the core area that ranges appeared to be used by individuals. The distance from roost to feeding areas varied by up to 7.4 km, but the bat usually commuted along lines of trees and hedges and over pastures. This resulted in greater distances being travelled than if they had flown by a direct route. On average, individuals commuted distances of 8 km each night between feeding areas, with a maximum distance of over 41 km. They visited between 0 and 10 feeding sites each night (mean = 2.89).     

Natal dispersal and its consequences in Black Grouse Tetrao tetrix

Data on dispersal distances of juveniles are important for understanding the genetic structure of populations, population regulation processes and the effects of landscape ecology on metapopulation dynamics. We studied dispersal in juvenile Black Grouse Tetrao tetrix in the French Alps between 1990 and 1998, by radiotracking 39 young grouse captured in August or autumn in a study area of 836 ha. Natal dispersal occurred in two discrete phases, autumn (October) and spring (mid-April to early May), with periods of reduced mobility between. The mean distance travelled by females exceeded that of males in autumn but not in spring. The natal dispersal distance of females was greater than that of males, and resulted in 81% of females leaving the study area to nest 5–29 km from their site of capture. This emigration must have been compensated for by immigrants because the number of hens in the study area increased during the study. Males were more philopatric. By the summer after capture, only 9% had emigrated from the study area. Despite the longer dispersal distances of females, there was no difference in the survival functions of the sexes between the ages of 6 weeks and 13 months.     

Travel distance and mass gain in wintering blackbirds

Birds that range over a large area will have a greater mass-dependent risk of predation than more sedentary birds. Birds that travel more may then reduce winter mass gain to compensate for the increased predation risk that greater travelling entails. I tested whether European blackbirds, Turdus merula, that travelled more in winter had a lower mass than more sedentary birds, independently of any confounding effects of food supply on both ranging behaviour and mass gain. I measured change in winter mass and amount of food eaten in conjunction with the distance that blackbirds travelled to a randomly sited mobile feeder. Blackbirds that travelled shorter distances (per trip and in total) and less often to the feeder had the highest mass midwinter relative to their spring mass. Blackbirds with a higher mean mass midwinter also travelled, on average, shorter distances to the feeder. The distance an individual blackbird travelled to the feeder at any one time was probably independent of the state of its daily energy reserves (how much of its daily total mass gain it had achieved at that point). The relationship between distance travelled and mass was probably independent of food supply because distances actually increased at the end of the winter and the amount of food eaten per individual changed little. More mobile blackbirds were therefore likely to have compensated for any increases in predation risk associated with their greater ranges by decreasing winter mass gain, but will have had an increased risk of starvation because of their lower mass. Copyright 1999 The Association for the Study of Animal Behaviour.     

MOVEMENTS OF SATELLITE-TAGGED SUBADULT AND ADULT HARBOR SEALS IN PRINCE WILLIAM SOUND, ALASKA

Satellite-linked tags were attached to 49 subadult and adult harbor seals captured in Prince William Sound (PWS), Alaska, and their movements were monitored during 1992–1997. Seals were tracked for a total of 5,517 seal-days and were located on about 80% of the days that tags transmitted. Most locations were in or near PWS, but some juvenile seals moved 300–500 km east and west into the Gulf of Alaska. While several seals travelled to 50–100 km offshore, virtually all locations were in water <200 m deep. Overall, juvenile seals moved more than adults and had larger home ranges. Movements were significantly affected by month, and age by month and sex by month interactions. In all months, mean distances between successively used haulouts were <10 km for adults and <20 km for juveniles. Mean monthly home ranges varied from <100 km² to >1,500 km², and were smallest during June-July. Mean haul-out to at-sea distance was 5–10 km for adults and generally 10–25 km for juveniles. Satellite-linked tags provided an effective means of monitoring and describing the full range of harbor seal movements in this region, with the exception of late summer when tags were shed during the molt.     

Winter movements and activity of signal crayfish Pacifastacus leniusculus in an upland river,determined by radio telemetry

Radio-telemetry was used to study the late autumn and winter movements of twenty adult signal crayfish Pacifastacus leniusculus (32.9–63.8 mm carapace length) an introduced exotic crayfish species, in the upland River Wharfe, northern England. The distances moved during the study varied greatly between individuals (0–328 m). Movements were generally sporadic; crayfish would remain in one position for several weeks and make occasional movements to new locations. Total distances travelled, linear range and ranging area did not differ significantly between males and females. The distance travelled in upstream and downstream directions did not differ significantly and there was no correlation between distance travelled and crayfish size. Several high flow events occurred during the study, but these did not cause any mortality or apparent displacement of crayfish downstream, suggesting that this is not a significant factor in downstream dispersal or mortality of adults of this invasive crayfish species in winter. A marked reduction in large-scale movements occurred in mid-December which coincided with a decline in water temperature. There was a less distinct pattern in local activity which was strongly correlated with water temperature and varied before and after mid-December.     

Pattern of movements of adult Barbus haasi in a small Mediterranean stream

Most adult Barbus haasi , at a 1950 m-long site in Vallvidrera creek, were highly sedentary and resided within a home range <20 m (32 m²), while a small group were more mobile. On successive sampling occasions, between 52·3 and 64·9% of fish were recaptured in the same 10-m-long section in which they had previously been captured. Movements over long distances were infrequent, and only 5·6% of the fish moved >100 m. The movement pattern of the population was seasonally stable, although the mean distances were slightly greater in summer because of the medium-range movements of a few individuals. Overall, upstream and downstream movements were equally common but a significant downstream movement occurred in spring. The size of the fish did not influence the movement rate. Fish inhabiting those sections of the stream with greater depth, slower current and more cover had a lower movement rate than fish occupying shallower, exposed sections. The restricted movement of B. haasi could increase the survival of fish by increasing the probability of staying in the remaining pools during summer dry-out, and may therefore be of adaptive significance.     

利用无线电技术对达乌尔鼠兔巢区的研究

达乌尔鼠兔是内蒙古草原斑块分布的一种害鼠。它们在斑块间的扩散对其种群调节和进化都有重要意义。文章对两个家族的达乌尔鼠兔进行了无线电遥测研究。它们的巢区面积从3138M²到17062M²,核心区面积从1292M²到7808M²。雄性—雌性巢区重叠面积比雌性—雌性巢区重叠面积大。该鼠的扩散和探索距离可达 200m.从9月开始鼠兔的活动就很活跃,尤其是探索活动和扩散。多数扩散个体在移居点很快消失。     

瑞士西部农田周围生态保留带中小型兽类种群结构特征及数量动态的初步研究

为了评价生态保留带对小型兽类种群的影响,2003年7月至2004年6月在瑞士西部Salavaux,chevmux和Montbrelloz 3个地区采用标志重捕方法对小型兽类种群进行了研究。在3个生态保留带中,共发现6种1206只小型兽类,其中普通田鼠、小林姬鼠、中麝晌捕获数量多。普通田鼠为优势种。普通田鼠的种群数量在生态保留带间有差异,但具有相同的季节性波动趋势,一般种群数量随着植被覆盖度和食物丰富度的增加,春季末开始出现增加,仲夏达到最高水平。种群中雌雄个体年龄结构之间有明显的差异,成体和亚成体的数量比幼体多,雄性亚成体的数量比雌性多,雌性成体数量比雄性多（X^2=44．09,df=10,P〈0．001,N=203）。普通田鼠种群中雌雄个体体重之间有明显的差异,雄性的体重比雌性大（t一检验：t=5．011,df=162,P〈0．05,N=213）。种群性比之间有明显的月间变化,雌性的捕获次数比雄性大。普通田鼠只在短距离范围内活动,在生态保留带中的巢区为350～400m^2,雌雄个体的巢区大小之间没有显著性差异。     

Eliminating autocorrelation reduces biological relevance of home range estimates

1. Destructive subsampling or restrictive sampling are often standard procedures to obtain independence of spatial observations in home range analyses. We examined whether home range estimators based upon kernel densities require serial independence of observations, by using a Monte Carlo simulation, antler flies and snapping turtles as models.
2. Home range size, time partitioning and total straight line distances travelled were tested to determine if subsampling improved kernel performance and estimation of home range parameters.
3. The accuracy and precision of home range estimates from the simulated data set improved at shorter time intervals despite the increase in autocorrelation among the observations.
4. Subsampling did not reduce autocorrelation among locational observations of snapping turtles or antler flies, and home range size, time partitioning and total distance travelled were better represented by autocorrelated observations.
5. We found that kernel densities do not require serial independence of observations when estimating home range, and we recommend that researchers maximize the number of observations using constant time intervals to increase the accuracy and precision of their estimates.     

Spatio-temporal ecology and density of badgers <Emphasis Type="Italic">Meles meles</Emphasis> in the Swiss Jura Mountains

This study reports for the first time data on the spatio-temporal ecology of badgers living in a cold and wet mountain region (Swiss Jura Mountains). The home range, movements, activity patterns and habitat use of three badgers (two males, one female) were examined using radiotelemetry. Average home range size was 320 ha (MCP 100%), but the ranging behaviour of badgers varied at a seasonal scale. As in other regions, badgers were strictly nocturnal or crepuscular and showed a marked reduction of activity in the winter period. From spring to autumn, animals were active for an average (±SD) of 8.1 ± 2.4 h and travelled up to 9,460 m each night (mean±SD, 5,160 ± 2,600 m). The nightly distance travelled by badgers was positively correlated with their travel speed, the duration of the activity period and the used area, but not with night length. Year-round, the radio-collared animals avoided pastures and the vicinity of houses during their night trips. In winter and spring, individual badgers used forests and wooded pastures more than expected according to their availability, whereas cereal fields were actively selected in summer and autumn. Den-watching, night-lighting and radio-tracking data suggest that badgers live in pairs in this wet and cold region. Population density estimates range from 0.4 to 1.5 individuals/100 ha. We discuss the importance of trophic resources and climate as factors influencing badger behavioural ecology.     

Wintering site fidelity and movement patterns of Western Sandpipers Calidris mauri in the San Francisco Bay estuary

Western Sandpipers Calidris mauri are the most numerous shorebird species in the San Francisco Bay estuary during winter. A sample of 106 Western Sandpipers was captured in mist nets and radio-marked with 1-g transmitters to examine their wintering site fidelity and movements. Differences in distances moved, home range extent and core area size were examined by age, sex, season, site, time of day and tide. All birds remained in the south San Francisco Bay region during winter and exhibited strong site fidelity, with a mean home range of 22.0 km² or only 8% of the study area. First-year birds had larger home ranges (26.6 ± 3.6 km²) than adults (17.2 ± 2.5 km²) in winter, but home range sizes of males and females were not significantly different in any period. Home range sizes were similar between seasons, but core areas were smaller in spring (6.3 ± 1.2 km²) than in early (9.6 ± 4.0 km²) or late (11.6 ± 1.6 km²) winter. Movements and home range size were similar for radio-marked birds located during day and night. The high degree of regional and local site fidelity demonstrated that the mixture of natural mud fiats and artificial salt ponds in southern San Francisco Bay provided sufficient resources for large wintering populations of Western Sandpipers.     

The diurnal periodicity and cycle of behaviour of the adult cabbage root fly (Erioischia brassicae)

Adult cabbage root fly (Erioischia brassicae (Bouché)) exhibited a diurnal periodicity in behaviour. Trapping tests indicated that the flies fed from hedgerow flowers in the morning, visited the crop in the early afternoon and returned to the hedges in the late afternoon. In the laboratory the flies also showed a cyclical pattern in behaviour. Feeding preceded oviposition by 3 days and this was reflected in the field by a relative increase in the movement of females away from the hedges and to the crop when they became gravid. The diurnal periodicity and the cycle in behaviour of males was similar to that of the females, indicating that some of the flies' movement was non-appetitive. The tendency of flies to stay for most of the day at hedges resulted in progressive declines in the numbers captured with increasing distances from hedges.     

Using Genealogical Mapping and Genetic Neighborhood Sizes to Quantify Dispersal Distances in the Neotropical Passerine,the Black-Capped Vireo

Dispersal is a key demographic process, ultimately responsible for genetic connectivity among populations. Despite its importance, quantifying dispersal within and between populations has proven difficult for many taxa. Even in passerines, which are among the most intensely studied, individual movement and its relation to gene flow remains poorly understood. In this study we used two parallel genetic approaches to quantify natal dispersal distances in a Neotropical migratory passerine, the black-capped vireo. First, we employed a strategy of sampling evenly across the landscape coupled with parentage assignment to map the genealogical relationships of individuals across the landscape, and estimate dispersal distances; next, we calculated Wright’s neighborhood size to estimate gene dispersal distances. We found that a high percentage of captured individuals were assigned at short distances within the natal population, and males were assigned to the natal population more often than females, confirming sex-biased dispersal. Parentage-based dispersal estimates averaged 2400m, whereas gene dispersal estimates indicated dispersal distances ranging from 1600–4200 m. Our study was successful in quantifying natal dispersal distances, linking individual movement to gene dispersal distances, while also providing a detailed look into the dispersal biology of Neotropical passerines. The high-resolution information was obtained with much reduced effort (sampling only 20% of breeding population) compared to mark-resight approaches, demonstrating the potential applicability of parentage-based approaches for quantifying dispersal in other vagile passerine species.     

Differential movement and activity patterns of sexes in a biparental beetle during the reproductive season

1. Biparental care is stabilised if parents perform different tasks during care. Specialised parental roles may require different time and energy budgets that in turn are expected to influence the activity and space use of sexes. 2. Here we investigate movement patterns of the biparental Lethrus apterus beetle using a grid of pitfall traps in their natural habitat. 3. Sexes of the burrow building L. apterus perform different roles during caregiving, as females collect most of the leaves, which serve as food for the offspring while paired males stay mostly in the burrow. We hypothesised that sex differences in mate search and parental activities are reflected in movement patterns. 4. We found that females frequently travelled short distances, whereas males were detected less often but when detected, they travelled significantly longer distances than females. 5. Our results are consistent with the notion that efficient parental food provisioning requires more localised movement and activity patterns. Furthermore, the long distance movements of some males may indicate active mate searching behaviour.     

Adult philopatry and dispersal in the field vol Microtus agrestis

Summary Using mark-recapture data, we related the movements of adult field voles to population density, sex ratio and population growth. Dispersal movements (defined as distances larger than 1 home range diameter) were few in both sexes; 4 out of 197 (2.0%) in males and 8 of 316 (2.5%) in females. The distance moved between sequential trapping periods was similar for males and females; the mean being 10.2 m and 9.0 m respectively. Both males and females moved larger distances during the breeding season than during the nonbreeding period. The distance moved between sequential trapping periods showed a strong negative relation to density, i.e. both sexes moved shorter distances at higher densities, but there were no differences between periods of increasing and declining population densities. These results contradict the dispersal predictions of all major hypotheses proposed to explain population fluctuations in small mammals. The dispersal patterns fit a geometric distribution, suggesting that competition is the primary factor determining the dispersal characteristics of this population.