home ranges
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Sociality in animal populations is a continuum, and interactions between conspecifics are meaningful for all vertebrates. Ignorance of social structures can lead to misunderstanding their ecology and, consequently, to unsuccessful species management. Here, we combined genetic and spatial data on radio-collared brown bears (Ursus arctos) to investigate kin-related home range overlap and kin-related centroid distance within central and eastern Finland. We found that the extent of home range overlap was positively correlated with relatedness among adult females. In addition, home range centroid distance decreased as relatedness increased. Moreover, there were significant differences between the two studied regions: female brown bears in central Finland were more closely related to each other, and the sizes of their home ranges were larger than those in eastern Finland. The smaller home ranges and lower degree of relatedness among bears in eastern Finland might be a result of the substantially higher hunting pressure in the area, combined with immigration of new unrelated individuals from Russia.

Abstract As urbanisation continues to reduce the available habitat for wildlife some species, such as the black-and-gold howler monkey (Alouatta caraya) in Pilar, southwest Paraguay, are making their homes in anthropogenic environments. Understanding an animal's home range is an important first step to understanding its ecological needs, an essential requirement for robust conservation plans. In this study we determined the home ranges and core areas of five groups of urban dwelling A. caraya using Minimum Convex Polygon (MCP) and Kernel Density Estimation (KDE) Analysis. We used a Spearman’s Correlation to explore the relationship between home range size and group size. All five groups had home ranges of less than 10 ha and used core areas of less than 1ha. Group size had no significant relationship to home range size. We provide the first estimates of home range for A. caraya in an urban environment in Paraguay. Though the home ranges of the urban A. caraya in Pilar, Paraguay fall at the smaller end of the spectrum of range sizes in Alouatta they are not abnormal for a species in this genus.

Globally, sea turtle research and conservation efforts are underway to identify important high-use areas where these imperiled individuals may be resident for weeks to months to years. In the southeastern Gulf of Mexico, recent telemetry studies highlighted post-nesting foraging sites for federally endangered green turtles (Chelonia mydas) around the Florida Keys. In order to delineate additional areas that may serve as inter-nesting, migratory, and foraging hotspots for reproductively active females nesting in peninsular southwest Florida, we satellite-tagged 14 green turtles that nested at two sites along the southeast Gulf of Mexico coastline between 2017 and 2019: Sanibel and Keewaydin Islands. Prior to this study, green turtles nesting in southwest Florida had not previously been tracked and their movements were unknown. We used switching state space modeling to show that an area off Cape Sable (Everglades), Florida Bay, and the Marquesas Keys are important foraging areas that support individuals that nest on southwest Florida mainland beaches. Turtles were tracked for 39–383 days, migrated for a mean of 4 days, and arrived at their respective foraging grounds in the months of July through September. Turtles remained resident in their respective foraging sites until tags failed, typically after several months, where they established mean home ranges (50% kernel density estimate) of 296 km2. Centroid locations for turtles at common foraging sites were 1.2–36.5 km apart. The area off southwest Florida Everglades appears to be a hotspot for these turtles during both inter-nesting and foraging; this location was also used by turtles that were previously satellite tagged in the Dry Tortugas after nesting. Further evaluation of this important habitat is warranted. Understanding where and when imperiled yet recovering green turtles forage and remain resident is key information for designing surveys of foraging resources and developing additional protection strategies intended to enhance population recovery trajectories.

In September 2019, two gravid female brown bears (Ursus arctos) were captured and equipped with GPS/GSM collars in Paklenica National Park (Croatia). Home ranges during hyperphagia were analyzed to describe the spatiotemporal requirements. Mean seasonal home ranges were very small with 9.2 km2 and 7.5 km2 (Brownian Bridge Movement Model 95%). During the tracking period, both bears used different territories and showed little to no use of overlapping area. The bears in our study spent a considerable time in proximity of artificial feeding sites, indicating a probable use of these structures as a food resource (mean 15.7% and 30.7%). Furthermore, the bears approached very close to human structures such as 8.9 m and 4.4 m. As most encounters between humans and bears occur during hyperphagia, it is important to offer refugia from human disturbance, especially as the National Park is not only used by residents, but also by tourists. To adapt management according to the animal’s needs, further studies should include more individuals from different age and sex classes. Both females were gravid. It remains unclear whether gravidity has an effect on the home range and should be further investigated.

In northern Eurasia, large carnivores overlap with semi-domestic reindeer (Rangifer tarandus) and moose (Alces alces). In Scandinavia, previous studies have quantified brown bear (Ursus arctos) spring predation on neonates of reindeer (mostly in May) and moose (mostly in June). We explored if habitat selection by brown bears changed following resource pulses and whether these changes are more pronounced on those individuals characterised by higher predatory behaviour. Fifteen brown bears in northern Sweden (2010–2012) were fitted with GPS proximity collars, and 2585 female reindeers were collared with UHF transmitters. Clusters of bear positions were visited to investigate moose and reindeer predation. Bear kill rates and home ranges were calculated to examine bear movements and predatory behaviour. Bear habitat selection was modelled using resource selection functions over four periods (pre-calving, reindeer calving, moose calving, and post-calving). Coefficients of selection for areas closer to different land cover classes across periods were compared, examining the interactions between different degrees of predatory behaviour (i.e., high and low). Bear habitat selection differed throughout the periods and between low and high predatory bears. Differences among individuals’ predatory behaviour are reflected in the selection of habitat types, providing empirical evidence that different levels of specialization in foraging behaviour helps to explain individual variation in bear habitat selection.

Long distance, post-release movements of translocated wildlife can be a key factor limiting translocation success.  Yet, for many species, we have little or no understanding of factors that influence post-release movements.  Translocations have been important for recovering fisher Pekania pennanti populations across the southern portion of their North American range.  However, little is known about the post-release movements of translocated fishers and how these movements may be influenced by demographic or translocation-process factors.  To restore fishers in Washington State, we moved 90 fishers from central British Columbia and released them at nine sites in the Olympic Fisher Recovery Area on the Olympic Peninsula of Washington from 2008 to 2010. We evaluated post-release movements of 48 fishers to determine both the distance and duration of movements prior to home range establishment.  Fishers moved extensively following their release.  Multi-model selection indicated a high level of support for the hypothesis that post-release movements differed by fisher sex and age; whereas, year of release had no apparent effect on movements, and release date had only a marginal influence on male movements.  Mean distance (± 95% CI) from a release site to a home range was greater for adult males (62.0 ± 19.6 km) than for juvenile males (31.4 ± 16.0 km), adult females (30.9 ± 21.1 km), and juvenile females (29.0 ± 13.5 km).  Mean number of days from release until home range establishment was similar for the sexes, however the variance in movement duration was greater for females.  Twenty-six of 27 females established home ranges over an 11-month period (December-October), while 19 of 21 males did so within a 4-month period (April-July).  Mean home range sizes differed between males (128.3 ± 21.1 km2) and females (63.5 ± 9.0 km2) and were among the largest reported for the species.  A greater proportion of females (18 of 27; 67%) than males (8 of 21; 38%) established home ranges within or partially within the recovery area.  Six females left a previously established home range during the breeding season, presumably to find breeding males.  Given the large distances that fishers can move following release, translocation success could be furthered by releasing individuals at fewer sites in the interior of large reintroduction areas to facilitate greater exposure to a recovery area and greater opportunity to interact with conspecifics and potential mates.

<p>Translocations are increasingly being used for conservation management of threatened species (Sarrazin & Legendre, 2000). Outcomes are influenced by a range of factors including effects of early rearing experience, conspecific familiarity, density of resident conspecifics, and habitat quality at the release site, all of which may impact on the behaviour of released individuals and subsequent survival and fitness (Law & Linklater, 2007; Linklater & Swaisgood, 2008; Sarrazin & Legendre, 2000). Conservation success, defined as the realisation of goals set out at the start of a project, can be improved by detecting factors causing suboptimal outcomes and identifying potential solutions (Buner et al., 2011; Green et al., 2005; Mihoub et al., 2011).  I aimed to expand current knowledge on factors influencing translocation outcomes by investigating the conservation management of the rowi (Apteryx rowi), the rarest species of kiwi. Current rowi conservation practices provide an opportunity to investigate this type of translocation management model. I provide new evidence and knowledge of behavioural mechanisms driving translocation success, include an expansion of current home range cognitive mapping theory relevant to conservation translocations, and present the first study of rowi home range behaviour (defined as the pattern of space use which leads to the emergence of a stable home range). Rowi conservation management involves removing eggs from the wild, hatching chicks in captivity, rearing on a predator free island until they are large enough to no longer be at risk of predation by stoats (Mustela erminae), then translocation back into the single remaining mainland population at Ōkārito forest. Over three years, experimental releases (n=66) were undertaken into both the existing population of rowi at South Ōkārito, and into an adjacent but unoccupied area of their former range at North Ōkārito. After intensive post-release monitoring, the effects of various elements of the translocation process on post-release survival, dispersal, conspecific association, habitat selection and home range behaviour were examined.  An investigation into the effects of season of release, conspecific density, sex, and release group size on survival during the 90 day critical period following release, found release season and release group size are the most likely factors to influence post-release survival, with highest survival in spring, and for large release groups of four or more birds per release site. Habitat quality throughout the Ōkārito forest was estimated using invertebrate biomass as a proxy. A Geographic Information Systems (GIS) layer showing relative estimated invertebrate biomass was created and used to provide values of habitat quality at release locations and within home ranges. An investigation of the influence of habitat quality on post-release dispersal, conspecific association and home range behaviour found maximum dispersal distance was affected by the release site (North or South Ōkārito), and the interaction of release site and the estimated invertebrate biomass at the release location. Mean home ranges (± SE) of translocated rowi (3.35 ± 0.37 km²), were larger and of lower habitat quality than those of wild rowi (1.06 ± 0.09 km²). No effects of release group size on dispersal distance or conspecific association rates post-release were found.  The effects of early rearing experience are proposed as a key factor influencing translocated rowi behaviour. By monitoring the survival, dispersal, conspecific association and home range behaviour resulting from the translocation of rowi reared in a non-natural social situation, I highlight the potential impact of prior social experience and social memory on cognitive mapping and home range establishment. This innovative approach has the potential to be a valuable expansion to current home range cognitive mapping theory, and warrants further study.  Translocation is a vital tool in conservation, and has undoubtedly been instrumental in improving the situation of rowi since the first application to rowi conservation in the 1990s. This study has demonstrated that further improvements in the effectiveness and efficiency of translocations for conservation can be gained through sound scientific analysis of factors affecting the mechanisms leading to translocation success. Ongoing monitoring, analysis and reassessment of translocation management practices are recommended to ensure optimal conservation outcomes.</p>

The Timber Rattlesnake (Crotalus horridus) has a large distribution spanning much of the eastern United States. Because temperature, habitat type, prey composition and abundance, and a variety of other factors may dictate reptile behavior, populations of conspecific species may exhibit behavioral differences across latitudinal and elevational gradients. Using radio telemetry, we tracked 10 adult Timber Rattlesnakes (7 males, 3 females) from May 2016 to June 2017 in southeastern Louisiana to examine the spatial ecology of male and non-gravid female snakes. Mean annual and seasonal home ranges of non-gravid female Timber Rattlesnakes were not statistically different from that of males. Mean seasonal home range sizes and average distances travelled of both sexes was smallest in winter, and had a general increasing trend beginning in spring with a peak in fall. These increases seemed to coincide with the breeding season, taking place from early July until the end of November. Comparison of this study with other studies throughout its distribution could have implications towards future management of conservation for other southern populations of Timber Rattlesnakes.

<p>Translocations are increasingly being used for conservation management of threatened species (Sarrazin & Legendre, 2000). Outcomes are influenced by a range of factors including effects of early rearing experience, conspecific familiarity, density of resident conspecifics, and habitat quality at the release site, all of which may impact on the behaviour of released individuals and subsequent survival and fitness (Law & Linklater, 2007; Linklater & Swaisgood, 2008; Sarrazin & Legendre, 2000). Conservation success, defined as the realisation of goals set out at the start of a project, can be improved by detecting factors causing suboptimal outcomes and identifying potential solutions (Buner et al., 2011; Green et al., 2005; Mihoub et al., 2011).  I aimed to expand current knowledge on factors influencing translocation outcomes by investigating the conservation management of the rowi (Apteryx rowi), the rarest species of kiwi. Current rowi conservation practices provide an opportunity to investigate this type of translocation management model. I provide new evidence and knowledge of behavioural mechanisms driving translocation success, include an expansion of current home range cognitive mapping theory relevant to conservation translocations, and present the first study of rowi home range behaviour (defined as the pattern of space use which leads to the emergence of a stable home range). Rowi conservation management involves removing eggs from the wild, hatching chicks in captivity, rearing on a predator free island until they are large enough to no longer be at risk of predation by stoats (Mustela erminae), then translocation back into the single remaining mainland population at Ōkārito forest. Over three years, experimental releases (n=66) were undertaken into both the existing population of rowi at South Ōkārito, and into an adjacent but unoccupied area of their former range at North Ōkārito. After intensive post-release monitoring, the effects of various elements of the translocation process on post-release survival, dispersal, conspecific association, habitat selection and home range behaviour were examined.  An investigation into the effects of season of release, conspecific density, sex, and release group size on survival during the 90 day critical period following release, found release season and release group size are the most likely factors to influence post-release survival, with highest survival in spring, and for large release groups of four or more birds per release site. Habitat quality throughout the Ōkārito forest was estimated using invertebrate biomass as a proxy. A Geographic Information Systems (GIS) layer showing relative estimated invertebrate biomass was created and used to provide values of habitat quality at release locations and within home ranges. An investigation of the influence of habitat quality on post-release dispersal, conspecific association and home range behaviour found maximum dispersal distance was affected by the release site (North or South Ōkārito), and the interaction of release site and the estimated invertebrate biomass at the release location. Mean home ranges (± SE) of translocated rowi (3.35 ± 0.37 km²), were larger and of lower habitat quality than those of wild rowi (1.06 ± 0.09 km²). No effects of release group size on dispersal distance or conspecific association rates post-release were found.  The effects of early rearing experience are proposed as a key factor influencing translocated rowi behaviour. By monitoring the survival, dispersal, conspecific association and home range behaviour resulting from the translocation of rowi reared in a non-natural social situation, I highlight the potential impact of prior social experience and social memory on cognitive mapping and home range establishment. This innovative approach has the potential to be a valuable expansion to current home range cognitive mapping theory, and warrants further study.  Translocation is a vital tool in conservation, and has undoubtedly been instrumental in improving the situation of rowi since the first application to rowi conservation in the 1990s. This study has demonstrated that further improvements in the effectiveness and efficiency of translocations for conservation can be gained through sound scientific analysis of factors affecting the mechanisms leading to translocation success. Ongoing monitoring, analysis and reassessment of translocation management practices are recommended to ensure optimal conservation outcomes.</p>