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The Eurasian otter (Lutra lutra) is among the most endangered mammals in Italy, its population being isolated and genetically distinct from other European populations. Yet, its ecology and behavior are largely unknown in Italy, preventing its much-needed effective conservation. We radio-tracked one male and one female otter daily in Southern Italy, for 1 year and 8 months, respectively. The male and female used nearly 30 and 20 km of river, respectively. The extension of the ranges varied among seasons. The male was more conservative in its spatial utilization, being mostly located around a trout farm. These first direct data on space use by wild Italian otters provided preliminary information potentially useful for a sound management of this endangered population.

Variation in an individual animal’s behavioural traits has been observed in a wide range of species and is believed to have important fitness consequences. As part of a larger study, it was observed that squirrels occurred at different densities on a 315 ha island, and this subsequently led to variations in faecal cortisol metabolite levels. This study aimed to examine whether living at different densities would also lead to variations in activity and aggression levels and in their survival probability, breeding and body condition. In order to examine variations in activity and aggression, behavioural tests (open field test, mirror image stimulation, breath rates and struggle rate tests) were conducted on 32 individuals (15♀, 17♂), a total of 69 times. Activity in the wild was investigated through radio tracking. There was a significant correlation between the time a squirrel was active and in their aggressive behaviour during the behavioural tests, with more aggressive individuals also being more active. Squirrels in the low density area spent a greater proportion of time active and engaged in aggressive behaviour in the open field test but also moved further in the wild and had a lower breath rate and higher struggle rates. Squirrels in the high density area were the least aggressive, had a smaller home range and higher breath and lower struggle rates. However, this was found to have no effect on survival probability, breeding or body condition. These variations may be the result of sampling dispersing squirrels.

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.

The trap-neuter-release method, which has been used to control stray cat populations in many countries, is thought to be more efficient than the trap-removal method because neutered cats returning to their home ranges can prevent the influx of other cats, which would otherwise take advantage of the unoccupied areas. To test territory occupying patterns of stray cats, the present study used radio tracking to estimate the home ranges of the cats living in Mt. Dobong, Korea. Total six cats (three males, three females) were radio tracked for 3–6 months. The mean home range size of the cats was relatively small (17.9–37.9 ha), and the home range sizes of males (21.6–37.9 ha) and females (17.9– 20.9 ha) were not significantly different. The home ranges of both male and female cats overlapped substantially, so that home ranges were not used exclusively at least within a sex. Furthermore, the overlap areas were associated with food-rich locations, such as garbage boxes. Therefore the present study failed to support the hypothesis that the cats would use their home ranges exclusively, thereby suggesting that the efficacy of the trap-neuter-return method should be reconsidered.

In the current context of the anthropocene, the original habitats of many species have been modified or destroyed. Animals may be forced to move from their original habitats, either to refuge habitats that are suboptimal natural habitats, or to substitution habitats that are anthropogenic. The quality of refuge habitats may be lower than that of the original ones, whereas substitution habitats may be of a similar or even better quality. Here, we test this hypothesis empirically, using the example of coastal populations of the bluethroat, Luscinina svecica namnetum. In a radio-tracking survey, we compared the home-range sizes (considered here a proxy of habitat quality) of the breeding males in their original (coastal saltmarshes), refuge (inland reedbeds) and substitution (coastal salinas) habitats. We found that home ranges are up to 15 times larger in the substitution habitat than in the original one, and intermediate in the refuge habitat, suggesting that substitution habitats have the lowest quality and original habitats the highest. To date, most studies and conservation programs related to this species have focused on its substitution habitats. This result challenges the interest of focusing on anthropogenic habitats when studying and conserving such a species, because such habitats may only be low-quality substitutes.

We studied home range size and maximum dispersal distance from hibernacula in Northern Pinesnakes (Pituophis m. melanoleucus) at a 1418-ha preserve in Cumberland County, New Jersey, USA, between 1993 and 2003. We discovered 22 different winter hibernacula that were used by 39 Northern Pinesnakes. Of the 10 snakes monitored in hibernacula for 3–5 yr, shifting was observed by 8 individuals, and 2 females showed hibernacula philopatry for five consecutive years. The average minimum convex polygon home range of 14 radio-tracked Northern Pinesnakes was 105.51 ha (located 30–108 times/snake), whereas the average kernel density estimator home range was 50% isopleth = 38.99 ha and 90% isopleth = 133.15 ha. There were no differences in home range as a function of sex, but the number of years snakes were radio-tracked affected home range size. An adult male had the largest home range of 258 ha. The average distance traveled by radio-tracked Northern Pinesnakes from their winter hibernacula was 1321.0...

International audience; The highly fragmented landscape structures of coastal salinas are known to result in decreased terrestrial bird abundance, species richness and diversity but to promote original assemblages dominated by specialist species, such as the Bluethroat Luscinia svecica namnetum. This species is mainly found at the core of these salinas, where the landscape characteristics are a priori the most hostile for terrestrial birds. The aim of this study was to test whether individuals of a specialized species like the Bluethroat may offset such landscape constraints by expanding their home ranges. We therefore radio-tracked 21 males in 2013 and 2014 in the salinas of the Marais du Mès (Parc Naturel Régional de Brière, Western France). The data of the 18 best-monitored males were used to carry out a hierarchical partitioning of variance to test the relative influence of landscape characteristics, individual characteristicsand distance to other males on their home-range sizes. We found that landscape characteristics were the factors that best explained home range sizes. Home-range sizes were significantly smaller in diversified landscapes composed of tidal creeks and salt-marsh patches and tended to be larger in landscapes dominated by the aquatic matrix consisting of water ponds. The results of this study demonstrate that although a few bird species are able toselect a priori hostile landscapes, they can offset such constraints by expanding their home-range size.

This study provides for the first time in the Carpathians analysis of spatial behaviour of 20 male red deer monitored during 2005–2013 using radio-telemetry. Two distinct spatial patterns were displayed in the same local population, i.e. residential and migratory. Residential annual home ranges were significantly smaller compared to migratory ones using both Minimum Convex Polygon and Kernel Home Range, due to periodic movement of migrants between distinct seasonal ranges. Residents remained in the same area throughout the year and showed a positive age effect on the home range size. While seasonal ranges of migrants were comparable in size, residents surprisingly expanded their space use in winter compared to other seasons. Fidelity to seasonal ranges over the years, especially winter, was striking and comparable in both migrants and residents with increasing tendency throughout the year (37–68 %). Vertical differences in home range altitudes were most obvious in migrants, although in both migrant types, significant descent was recorded during the winter. The longest horizontal movements were recorded in three young stags emigrating to neighbouring mountain ranges (30, 47 and 65 km). Because 45 % of the population seems to be migratory, the data support importance of large-scale hunting management established in Slovakia in 2009.

In order to assess the efficacy of reinforcement as a conservation tool for rehabilitated elongated tortoises Indotestudo elongata (Blyth, 1854) we released 10 adults equipped with radio tracking transmitters to the Kulen Promtep Wildlife Sanctuary in northern Cambodia. Based on short-term success indicators for reintroduction studies on reptiles we studied the tortoises’ adaptation to the new environment for five months. The tortoises successfully settled in the new environment without showing adverse effects regarding their behaviour, condition index (CI) and physical appearance. The annual survival rate was 76%. Based on individual locations collected, we analysed the tortoises’ movement patterns including daily displacement, five-month and seasonal home range sizes using minimum convex polygons (MCPs) and fixed kernel density estimators (KDEs).

Adult Podocnemis unifilis were monitored using VHF radio tracking from September 2013 to September 2014 in the Rio Trombetas Biological Reserve, Para, Brazil. Our aim was to analyze the use of space by this species near the nesting beach base by describing size and overlap of estimated home ranges. Transmitters were attached to 10 males and 10 females. The mean home range size calculated through the fixed-kernel (FK) method with 95% of the fixes was 79.28 ± 77.08 ha (0.56–215.07 ha; n = 13). The mean of overlapping areas was 14% with FK95% (0.02%–81%; n = 13) and 5% with FK50% (0.1%–23%; n = 9). There was a significant difference in the mean overlapping areas between females and males. The analysis of the overlap of activity centers estimated by FK50% is extremely important for the establishment of conservation strategies in the management plan for this species in the reserve. We were able to identify 2 critical areas for the maintenance of this population where there was a frequent overlap of activity centers: the first, identified during the dry season, was composed of small overlaps among 7 turtles and was near the nesting areas on the clay banks within the Lago Jacare; the second, identified during the rainy season, was composed of a concentration of overlap areas of larger size among 6 turtles and was an open area in the flooded forest. It is important not only to protect the nesting areas during the dry season but also to protect flooded forest areas with the major intensity of use along with the canals that link the flooded forests to the lakes in the rainy season. For conservation purposes, it is necessary to continue the protection of the nesting beaches throughout the savannas inside the lake where the species nests in the dry season. The flooded forest areas that are zones of intense use during the rainy season, and the canals where the turtles can move between lakes must be protected throughout the year.

Very little is known about the home range and movement patterns of tinamous. The Ornate Tinamou (Nothoprocta ornata), a species of the central Andes that is important for cynegetic and biomonitoring purposes, was previously reported to have a very small territory (2.43 ha). This was based solely on field observations. In order to gain a better understanding of the movement patterns, home range size, and home range overlap of this species, we radio tracked 12 adult individuals in an Andean agro-ecosystem for a full year. The birds remained within their home ranges all year; 100% MCP (minimum convex polygon) home ranges were 43.8 ± 21.6 ha (22–85 ha), 95% kernel home ranges were 58.8 ± 31.9 ha (25–118 ha) and 50% kernel core areas were 15.3 ± 8.9 ha (6–33 ha). Only two birds, probably sub-adults, showed extensive movement patterns before their death. Individuals overlapped their home ranges extensively (from 30–98% with 2–3 tagged individuals), but these values were probably higher because a small ...

The water deer (Hydropotes inermis) is one of the most primitive extant deer of the family Cervidae. Unlike Chinese water deer, Korean water deer have rarely been studied, even though they have relatively well remained in Korea. In particular, the home range of the Korean water deer has not yet been studied. Here we estimated the home range of the Korean water deer using two different methods (GPS and radio tracking) and analyzed the home range according to sex, time, and season. The mean home range size of four individuals was 2.77 and 0.34 under the 95% minimum convex polygon (MCP) and the 50% kernel (K) method, respectively. There seemed to be a difference in home range size between males (3.30 ) and females (2.25 ) under the 95% MCP method. We also found a difference in home range size between day (1.90 ) and night (2.43 ) by 95% MCP method. In addition, a home range size difference was observed between summer (4.65 ) and spring (0.48 ) or fall (0.85 ) using the 95% MCP method. Water deer seemed to have a larger home range in night than in day, and males also have a larger home range. We presumed that the GPS tracking method of the code division multiple access system could be a very useful tool for understanding the ecology of the water deer using the radio tracking method. Using these tracking methods and through future research, we can better understand the habitat use pattern of these water deer.

Some species of carnivores fluctuate between a primarily solitary lifestyle and a group-living lifestyle, depending on resource availability. Understanding the ontogeny of this transition requires analyzing changes in space use. We analyzed radio-telemetry data from 41 adult raccoons Procyon lotor to assess the influence of an experimentally maintained clumped food source on spatial structure. We compared home-range size, two-dimensional overlap and volume of intersection (VI) values between 22 raccoons with access to the clumped food resource and 19 raccoons on an adjacent control site that received similar food quantities, but for which food was distributed in a non-clumped and spatially-temporally unpredictable pattern. No between-sex differences in home-range size occurred within either food site, nor did differences in home-range size occur between the two sites. However, the experimental-site animals had two-dimensional home-range overlap values and volume of intersection (VI) scores that w...

Currently, telemetry appeared as a common method to reveal home range and movement of animal. However, the telemetry method was not applied for small-clawed otter yet. We have spent efforts to use the telemetry methods from March to August 2016 in a rice field landscape in Lubuk Alung district, Padang Pariaman regency, West Sumatra. We trapped individuals of small-clawed otters (Aonyx cinereus) using leg-hold traps and box traps. We implanted radio transmitter intraperitoneally. Movement of the animal was recorded using triangulation methods. Two male individuals of small-clawed otters were captured. One individual died soon after the transmitter implantation and another individual was successfully implanted and released. However the individual were detected for 28 hours only. In this paper, we described the efforts and problems appeared from the trapping, transmitter implantation, releasing and radio tracking process.

Home ranges of individuals of the gray four-eyed opossum Philander frenatus were studied by capture-mark-recapture (CMR) and radiotelemetry, within a set of eight Atlantic Forest fragments surrounded by a grassland matrix in the state of Rio de Janeiro, southeastern Brazil. Trapping sessions were carried out in all the forest fragments and in the grassland matrix. Adult individuals were fitted with radio-collar transmitters and monitored throughout the night. Locations were obtained by the “homing-in on the animal” method. Home-range sizes of the individuals with five or more captures or locations were estimated through the minimum convex polygon method. Home-range sizes estimated by radiotelemetry ranged from 0.6 to 7.4 ha (n = 8), and by CMR ranged from 0.1 to 12.1 ha (n = 17); home-range sizes estimated by radiotelemetry did not differ significantly from those based on CMR. However, comparing radiotelemetry with different CMR designs, the former estimates were larger than those based on either CMR using a single grid or CMR using two grids, but not larger than those based on multiple-grid CMR. In specific cases, animals monitored via radiotelemetry for only one or two nights showed larger home ranges than most individuals for which home ranges were estimated by CMR. Two individuals for which home-range sizes were estimated by both techniques showed larger home ranges when data from radiotelemetry were used. These data indicated that CMR can provide results comparable to radiotelemetry when multiple grids, spread across the landscape, are used, although this necessitates an intensive trapping effort. On the other hand, single- and double-grid CMR tend to underestimate home-ranges compared to radiotelemetry.

Here, we used radiotelemetry to determine home range and movement patterns of the frugivorous bat Sturnira lilium in a naturally fragmented landscape in Beni, Bolivia. Four females were monitored for up to 7 d. Based on 575 radiotelemetry positions, kernel home ranges were between 36.5 and 90.7 ha. During each night, bats visited most of their home range, which included forest islands and continuous forest; however activity was concentrated in core-use areas representing 6-12 percent of the home ranges. There was moderate overlap in home range and core-use areas among the four females. The mean long axis across the kernel home ranges was 1324 m. The results reported here show that S. lilium is able to move freely among forest elements in the landscape while crossing a savanna matrix. Hence, S. lilium may contribute to maintain connectivity and ecological processes in a fragmented landscape.

The hypothesis that vagility, or tendency to move, in pike Esox lucius can be predicted from individual home range was tested using telemetry. Independently of fish size, mean annual excursion distance was positively correlated to winter (0·02–0·95 ha) and spring (0·02–0·59 ha) home ranges but not summer and autumn home ranges.

Despite their likely ecological importance, the basic biology of Cooper's (Accipiter cooperii) and Sharp-shinned (A. striatus) Hawks remains poorly understood. This is particularly true during the winter, when even basic information on the spatial ecology of these species is largely unknown. Thus, we characterized the home range size and habitat chosen by these species as part of a larger study on wintering Accipiter hawks. We also compared our findings of bird feeder use by Cooper's Hawks to our previously published study on Sharp-shinned Hawks. During the winters of 1999–2004, we intensively radio-tracked 21 Sharp-shinned Hawks and six Cooper's Hawks in rural areas, and eight Cooper's Hawks in urban areas. We found that Sharp-shinned Hawks and Cooper's Hawks in rural areas used significantly larger areas than did Cooper's Hawks in urban areas, and that adult hawks generally used smaller areas than immature individuals. Habitat use by Cooper's Hawks and Sharp-shinned Hawks in rural areas was nea...

The Namib Desert golden mole (Eremitalpa granti namibensis) is morphologically, physiologically and behaviourally specialized for living in the harsh loose-sand desert. Ecological studies have relied on visually tracking animals on the surface of sand dunes. A radio tag would allow individuals to be more reliably located, even while under the sand. We developed a radio attachment and gathered preliminary data on winter habitat use by six individuals during 21 days. We compare data from previous studies and suggest that the greater diurnal activity, smaller home ranges, and more restricted movement patterns that we found are related to the unusual thermal and metabolic biology of Eremitalpa.

Arvicanthis niloticus was radio-tracked in the grasslands of the Queen Elizabeth National Park in Uganda. Home range sizes calculated by Ranges V® using the Minimum Convex Polygon Method (at 95%) were on average 5.5 times larger in the bushland–grassland mosaic than those in the Abutilon guineense–Ocimum suave bushland. An inverse relation between home range size and population density was found. In both habitats the species was highly active during daylight hours but differed in activity patterns. Resume L'Arvicanthis niloticus fut suivi par radio-emetteur dans la prairie du Parc National de Queen Elizabeth en Ouganda. Les tailles des domaines vitaux calcules avec Ranges V®en se servant de la methode de polygones convexe minimum (a 95%) furent 5,5 fois plus grand en moyenne dans le terrain en mosaique de brousse et prairie que celles dans la brousse d’Abutilon guineense–Ocimum suave. Une relation inversee entre la taille des domaines vitaux et la densite de population fut observee. Dans les deux habitats les especes furent tres actives pendant le jour mais differa dans la configuration d'activite.

From August 2001 to July 2002 the home range and movements of seven Micoureus demerarae (Thomas, 1905) (three males and four females) were investigated using radio tracking in the União Biological Reserve, state of Rio de Janeiro, south-eastern Brazil. A total of 436 locations was obtained and home range estimated with fixed Kernel (95% of data points), and minimum convex polygon (MCP) methods, with 100 and 95% of data points. Male home ranges estimated by MCP (100%) ranged from 5.4-24.2 ha and females from 0.3-10.7 ha. Corresponding figures calculated with Kernel (95%) were 4-10.9 ha for males and 1.3-5.9 ha for females. Animals travelled on average 423 m/night, with males travelling significantly further (582.8 m/night) than females (335.1 m/night) (t test, t = 3.609, p = 0.001). We concluded that radio tracking produced much larger home ranges than those estimated with traditional live-trapping techniques, suggesting that the latter might underestimate ranging when the area covered with traps is relatively small (ca. 1 ha or less). Radio tracking also indicated that M. demerarae, although predominantly arboreal and weighting only ca. 130 g., has movements similar in magnitude to larger-sized terrestrial didelphimorph marsupials, such as Didelphis Linnaeus, 1758, Philander Linnaeus, 1758 and Metachirus (Desmarest, 1817).No período de agosto de 2001 a julho de 2002 a área de uso e o movimento de sete Micoureus demerarae (Thomas, 1905) (três machos e quatro fêmeas) foram acompanhados, através de rádio-telemetria, na Reserva Biológica União, Rio de Janeiro, sudeste do Brasil. Foi obtido um total de 436 localizações e estimou-se a área de uso através dos métodos Kernel fixo (95% das localizações) e polígono mínimo convexo (PMC), com 100 e 95% das localizações. A área de uso dos machos estimada pelo PMC (100%) variou de 5,4-24,2 ha e fêmeas de 0,3-10,7 ha. Áreas calculadas com Kernel (95%) foram 4-10,9 ha para machos e 1,3-5,9 ha para fêmeas. Os animais locomoveram em média 423 m/noite, com machos se deslocando mais (582,8 m/noite) que as fêmeas (335,1 m/noite) (Teste t; t = 3,609; p = 0,001). Concluímos que o rádio rastreamento proporcionou áreas de uso superiores ao de estudos tradicionais realizados com capturas em armadilhas, sugerindo que pode haver uma subestimativa quando a área coberta com armadilhas é relativamente pequena (1 ha ou menos). O rádio-rastreamento também indicou que M. demerarae, embora seja predominantemente arborícola e pesa cerca de 130 g, possui movimentos semelhantes em magnitude a marsupiais terrestres de maior porte, como Didelphis Linnaeus, 1758, Philander Linnaeus, 1758 and Metachirus (Desmarest, 1817).

Studies of urban wildlife are important because they can give us insight into both how animals adapt to novel environments and how some species survive and prosper in human-dominated landscapes. Urban zoological institutions provide an ideal setting for research on such species. We report on a study of the behavior and ecology of opossums (Didelphis virginiana) on the grounds of the St. Louis Zoological Park. We used radio tracking to investigate the movement patterns and den site use of opossums on the grounds of the zoo and compared the results to data available for opossums elsewhere. We find that urban opossums in the St. Louis zoo have smaller home ranges and move shorter distances than their rural counterparts. We suggest that increased food availability and decreased risk of predation might explain such differences, and we suspect that conditions are even more favorable to opossums in a zoological setting than in cities in general. Our findings illustrate that there is much to be learned from scientific study of the free-living animals found on zoological park grounds. Zoo Biol 24:197–213, 2005. � c 2005 Wiley-Liss, Inc.

Three male and two female ship rats (Rattus rattus) were radio‐tagged and tracked in beech (Nothofagus) forest in the Eglinton Valley, Fiordland, New Zealand over two field periods in 1996 and 2000. The home range of each animal was calculated using the minimum convex polygon method. Ranges of three male rats were 7.5, 9.1, and 11.4 ha whereas those of the female rats were 0.89 and 0.27 ha. The home ranges recorded for male rats were considerably larger than those reported from other studies in non‐beech forest. Ship rats are important predators of forest birds, and home range information could be used to provide a guide for trap or bait station spacing in beech forests. To carry out rat control in beech forests effectively, further studies are needed to determine if the results of this pilot study are typical, and if home ranges of ship rats change with season, or at various stages of the beech mast cycle.

From 1996 to 2000 the home ranges of 14 male fallow deerDama dama (Linnaeus, 1758) were studied in the San Rossore Preserve (Italy) using radio-telemetry. Mean size of annual home ranges was 588.9 ± 278.9 ha, calculated by MCP, and 337.5 ± 178.9 ha, using Kernel method, and was larger than that reported in published literature to date. The size of the seasonal home range estimated with the MCP method was 90.6 ± 129.1 ha during spring, 73.7 ± 67.9 ha in summer, 465.0 ± 230.6 ha in fall, and 65.6 ± 60.6 ha in winter. The Kernel method gave 84.7 ± 140.2 ha in spring, 61.3 ± 64.6 ha in summer, 306.0 ± 170.5 ha in fall, and 46.5 ± 44.0 ha during winter. The seasonal analysis suggested that bucks tended to occupy the same particular area from winter to summer, which was related to rich trophic resources, even despite of anthropic disturbance. During autumn, males reached the rutting site (a lek) that was 4 km distant from the areas occupied during the other three seasons. The lekking behaviour was the main factor influencing home range size.

In spite of the important role played by bats in tropical ecosystems, little is known about how they are affected by habitat fragmentation. By using a mark/recapture protocol and radiotelemetry techniques in a naturally fragmented landscape composed of primary forests and forest fragments surrounded by savannas in Alter do Chao, Para State, Brazil, we were able to track the movements of various species of bats, calculate the size of the area used, locate roosts and potential feeding areas, and determine preferred flight routes. We marked 3440 bats belonging to 44 species and recaptured 151 belonging to 14 species. The average distance between extra-site recaptures was 2.2 km. With the exception of bats marked in fragments and recaptured in forests, all other possible inter-habitat recaptures were observed. We selected 23 bats of 8 species for radiotelemetry and the areas used by them varied from 65 to 530 ha. Some species restricted their activity to the vicinity of their roosts, rarely moving more than 500 m away, but others traveled greater distances between roosts and foraging areas. All tracked bats flew over savannas, crossing distances from 0.5 to 2.5 km. Roost location and type varied among species, from individuals roosting alone in the foliage to colonies in buildings. Bats were highly mobile and savannas did not appear to inhibit the movements of some species, suggesting that a persistent biological flow may be maintained among isolated fragments, with bats acting as pollinators and seed dispersers.

Capsule Woodpigeons range over greater areas during winter than summer with winter dispersion greatest in the first two winters following fledging. Aims To radiotrack Woodpigeons, to analyse the BTO ringing recoveries and to examine ranging behaviour. Methods Movements of 19 adult and nine newly fledged Woodpigeons around a 1070-ha study site in eastern England were monitored by radiotracking. The BTO recovery data were analysed for birds ringed in arable areas of Britain during the period 1950 to 1999. Results The mean 95% minimum convex polygons during the summer were 254 ha for adults and 294 ha for juveniles. These ranges increased to 628 ha for adults and 1283 ha for juveniles during winter. Although they left the study area over the winter, some radiotagged juveniles returned to their natal areas the following summer. Winter dispersion followed by a return to the natal area the following summer only occurred for the first two years of life. Conclusion Although Woodpigeons are largely sedentary, the ...

(Wied-Neuwied, 1826) is a marsupial common in the Atlantic Forest and Cerrado but understudied. Thus, we estimated the size of the home range and shelter preferences for three individuals (one male and two females) of

Miniature radio-transmitters were used to follow movements over a 10-day period of the 10 g honey possum Tarsipes rostratus , and the areas covered were compared with home-range estimates calculated from long-term mark-and-recapture records using pitfall traps. The study was carried out in the Scott National Park, in the extreme south-west of Western Australia, and shows that honey possums may move far greater distances than is apparent from trapping records. The overall mean area used determined by radio-tracking was significantly larger at 0.54±0.19 ha than the apparent home range of 0.03 0.01 ha determined by trapping. The area used by males was significantly greater than that of females when measured by radio-telemetry (0.79±0.24 ha vs 0.14±0.08 ha, P = 0.058), but did not differ significantly when estimated from trapping records (0.03±0.01 ha vs 0.01±0.01 ha). These data suggest that honey possums frequent plant assemblages at night where they are vulnerable to pitfall trapping, but that males, particularly, spend the day in other areas that may be as far as 200 m distant.

We quantified home range size and habitat selection of seven female Northern Saw-whet Owls (Aegolius acadicus) on Assateague Island, Maryland, during the winters of 1996 and 1997. Home range size (95% fixed kernel) was 103.5 ha (± 50.3 SE). Home range size increased with time spent radio tracking as biweekly home ranges were smaller than those calculated for longer time periods. Home ranges often overlapped in time and space and in one instance the home range for one owl was completely within that of another owl. Northern Saw-whet Owls used primarily pine woods and shrub swamp habitats, with pine woods used more often than any other habitat type and significantly more than expected based on habitat availability.

Radio tracking has been extensively used to enhance our knowledge on the movement and home range of fish in general and salmonids in particular. However, the use of various temporal sampling protocols is likely to overlook fish movements, and produce experimental artefacts, the amplitude of which is unknown and may compromise comparison of fish behaviours revealed by different protocols. Starting from a day-by-day tracking study of brown trout in Belgian waters (Aisne stream, nine fish, minimum 39 daily locations per fish), we re-examined their home range and mobility, through a subsampling process, as if the fish had been located at longer time intervals (2–14 days). The estimates from subsamples were compared to the original data set in order to quantify the corresponding reduction of accuracy from observed data, and how far this could be predicted on the basis of locating frequency. The results clearly indicate that all intervals longer than one day generally generate substantial biases (reduction of accuracy from 0 to 82% for home range and from 5 to 92% for mobility) but these can be partly corrected through the use of predictive models. This analysis demonstrates that any comparison between studies relying on different locating frequencies can generate some ambiguity when interpreting biological phenomena or geographical differences.

Lemniscomys striatus was radio-tracked in the Imperata-Cymbopogon grassland of the Queen Elizabeth National Park in Uganda. Home range sizes calculated by Ranges V® using the minimum convex Polygon method (at 95%) in the postburnt grassland were on average 4.8 times larger than those before the fire. An inverse relation between home range size and population density was found. Lemniscomys striatus was diurnal with two activity peaks during daylight, but activity ended only after dusk. Resume On a etudieLemniscomys striatus par radio-tracking dans la prairie aImperata-Cymbopogon du Parc National Queen Elizabeth, en Ouganda. La taille des territoires calculees par Ranges V® en utilisant la methode du polygone convexe minimum (a 95%) dans la prairie apres les feux, etait en moyenne 4,8 fois plus grande que celles d' avant les feux. On a decouvert une relation inverse entre la taille du territoire et la densite de population. Lemniscomys striatus est diurne, avec deux pics d'activite pendant la journee, mais son activite ne cesse qu' apres le crepuscule.

Wolves (Canis lupus) (9 females and 2 males from 4 packs), were radio-tracked in a large Polish woodland in Bialowieza Primeval Forest in 1996–1999. Based on 360 days of radio tracking with locations taken at 30- or 15-min intervals, daily movement distances (DMDs) of wolves and their utilization of territories were analyzed. DMDs averaged 22.1 km for females and 27.6 km for males. In reproductive and subadult females, DMDs varied seasonally, with the shortest daily routes in May and the longest in autumn–winter. Little seasonal variation was observed in nonbreeding and unsuccessfully breeding adult females. An adult male covered the longest DMDs in February (mating season). The mean speed of travelling wolves was 2.2 km/h. Wolves' hunting activity affected the length and speed of their movements, both of which were higher before than after a kill was made. With growing abundance of prey, DMDs of wolves became shorter. Snow cover and rainfall had a negligible effect on wolf travel. The mean straight-line distance between consecutive daily locations (SLD) was 4.4 km, i.e., on average, 21% of the actual route covered by wolves. Daily ranges utilized by wolves averaged 21.4 km2, or 9% of the whole territory. Variation in SLDs and daily ranges was shaped predominantly by mating, breeding, and pup rearing. The pattern of territory use by wolves differed between seasons. In spring–summer, their movements concentrated around the breeding den and rendezvous sites, and the areas used on consecutive days overlapped extensively. In autumn–winter, wolves moved widely and utilized their territory in a rotational way, returning to the same parts every 6 days, on average. Rotational use is related to intense patrolling and defense of territory, but may also help wolves to avoid behavioral depression of prey availability.