scholarly journals Behavioural mechanisms affecting the success of translocations. An investigation using New Zealand’s rarest ratite, the rowi

2021 ◽  
Author(s):  
◽  
Rachael Abbott
Keyword(s):  
Home Range ◽  
Group Size ◽  
Habitat Quality ◽  
Cognitive Mapping ◽  
Conservation Management ◽  
Release Site ◽  
Dispersal Distance ◽  
Home Ranges ◽  
Release Group ◽  
Invertebrate Biomass

<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>

scholarly journals Behavioural mechanisms affecting the success of translocations. An investigation using New Zealand’s rarest ratite, the rowi

2021 ◽  
Author(s):  
◽  
Rachael Abbott
Keyword(s):  
Home Range ◽  
Group Size ◽  
Habitat Quality ◽  
Cognitive Mapping ◽  
Conservation Management ◽  
Release Site ◽  
Dispersal Distance ◽  
Home Ranges ◽  
Release Group ◽  
Invertebrate Biomass

<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>

Variation in the home-range size of the squirrel glider (Petaurus norfolcensis)

2010 ◽  
Vol 32 (2) ◽  
pp. 183 ◽  
Author(s):  
Ross L. Goldingay ◽  
David J. Sharpe ◽  
Matt D. J. Dobson
Keyword(s):  
Home Range ◽  
Habitat Quality ◽  
New South ◽  
Home Range Size ◽  
Range Size ◽  
Home Ranges ◽  
Minimum Convex Polygon ◽  
South Wales ◽  
Squirrel Glider ◽  
Range Estimate

The home-range area of animals may vary geographically and in response to habitat quality. We investigated the size of squirrel glider (Petaurus norfolcensis) home ranges near Brisbane, Queensland, and at Tea Gardens on the central coast of New South Wales. Habitat at both sites had been partially cleared and had been subjected to grazing for several decades. Twelve gliders were tracked over an average of 3.5 months in Brisbane. The fixed kernel (FK95%) home-range estimate averaged 4.6 ± 0.7 (s.e.) ha while the minimum convex polygon (MCP100%) averaged 6.7 ± 1.5 ha. Six gliders were tracked over 1 month at Tea Gardens. The FK95% home-range estimate averaged 14.8 ± 2.4 ha while the MCP100% averaged 13.3 ± 3.1 ha. The Tea Gardens values are derived from relatively short periods and are likely to underestimate the areas used. This study demonstrates that home-range size can vary substantially in the squirrel glider. This has implications for understanding how this species responds to variation in habitat quality and highlights the need for site-specific studies to inform aspects of management.

Dispersal and home-range dynamics of exotic, male sika deer in Maryland

2013 ◽  
Vol 40 (4) ◽  
pp. 328 ◽  
Author(s):  
David M. Kalb ◽  
Jacob L. Bowman ◽  
T. Brian Eyler
Keyword(s):  
Home Range ◽  
Species Interactions ◽  
Sika Deer ◽  
Cervus Nippon ◽  
Home Range Size ◽  
Dispersal Distance ◽  
Home Ranges ◽  
Long Distance ◽  
Variable Movement ◽  
Movement Group

Content An unknown number (n = four or five) and sex of sika deer (Cervus nippon yakushimae) were introduced to the Delmarva Peninsula, Maryland, in 1916. Since introduction, their population has grown exponentially. Aims The purpose of our study was to investigate dispersal and home-range size to enable better management of this exotic species in the presence of native white-tailed deer (Odocoileus virginianus). Methods We collected telemetry locations on 60 males (captured during their first winter) from 2008 to 2010. Animals were classified into three movement groups, including local, migratory and nomadic post-dispersal. Key results Average home-range sizes ranged from 464 to 4121 ha and were influenced by season and deer movement grouping (P = 0.0001). Of 20 deer that dispersed, 19 did so at 1 year of age. Dispersal distance and direction were random across the landscape (P = 0.899). Local deer were the most common movement group (70%; 42 of 60) and were characterised by short movements confined to a well established home range. We observed 14 deer migrations, characterised by round-trip movements associated with seasons and directionality (P = 0.003). Four deer were classified as nomadic and had long-distance movements across the landscape unassociated with seasons. Conclusions To aid managers in controlling the expansion of the population, we provide data regarding the manner, distance and direction that sika deer move. Our results show that sika deer have variable movement strategies and large home ranges. Implications Variation in movement types will influence spread of the population, confounding species interactions, management and harvest strategies. The present results may have implications to other areas that also have sika populations.

scholarly journals Territoriality, Prospecting, and Dispersal in Cooperatively Breeding Micronesian Kingfishers (Todiramphus Cinnamominus Reichenbachii)

The Auk ◽  
2007 ◽  
Vol 124 (2) ◽  
pp. 381-395 ◽  
Author(s):  
Dylan C. Kesler ◽  
Susan M. Haig
Keyword(s):  
Home Range ◽  
Home Range Size ◽  
Dispersal Distance ◽  
Home Ranges ◽  
Nest Sites ◽  
Cooperatively Breeding ◽  
Dispersal Behavior ◽  
Survival And Reproduction ◽  
Opposite Sex ◽  
Temporally Correlated

Abstract We investigated territoriality, prospecting, and dispersal behavior in cooperatively breeding Pohnpei Micronesian Kingfishers (Todiramphus cinnamominus reichenbachii) throughout the annual cycle using radiotelemetry and color-band resights. Mean home-range size was 6.3 ha and territories were 8.1 ha. Within territories, Micronesian Kingfishers shared 63% of their home-range space with coterritorial occupants, and 3% was shared with extraterritorial conspecifics. Birds on cooperative territories had larger home ranges that overlapped more with coterritory occupants' home ranges than birds in pair-held territories. Despite evidence suggesting that resources necessary for survival and reproduction occurred on each territory, Micronesian Kingfishers of all age and sex classes made extraterritorial prospecting movements. Prospecting was rare; it comprised only 4.3% of our observations. When birds departed on forays, they were gone for ∼1.9 h and returned to home territories before sunset. Prospecting by dominant birds was temporally correlated with courtship and nest initiation, and birds were observed at neighboring nest sites with opposite-sex conspecifics during the period when females were available for fertilization. Juveniles and helpers prospected throughout the year and made repeated homesteading movements to dispersal destinations before dispersing. Mean dispersal distance for radiomarked individuals was 849 m. Results suggest that prospecting in Micronesian Kingfishers is a complex behavior that provides information for dispersal decisions and familiarity with dispersal destinations. Additionally, extraterritorial movements may provide covert opportunities for reproduction, which have potential to profoundly influence the distribution of fitness among helper and dominant Micronesian Kingfishers. Territorialité, prospection et dispersion chez des Todiramphus cinnamominus reichenbachii présentant une reproduction coopérative

Effects of habitat quality and anthropogenic disturbance on grizzly bear (Ursus arctos horribilis) home-range fidelity

2015 ◽  
Vol 93 (11) ◽  
pp. 857-865 ◽  
Author(s):  
A.A. Sorensen ◽  
G.B. Stenhouse ◽  
M.L. Bourbonnais ◽  
T.A. Nelson
Keyword(s):  
Home Range ◽  
Habitat Quality ◽  
Industrial Development ◽  
Ursus Arctos ◽  
Rocky Mountain ◽  
Temporal Analysis ◽  
Home Ranges ◽  
Grizzly Bear ◽  
Ursus Arctos Horribilis ◽  
New Development

In the Rocky Mountain eastern slopes of Alberta, Canada, grizzly bears (Ursus arctos horribilis Ord, 1815) live in a landscape heavily impacted by industrial development and human disturbance. We characterized the role of changing habitat quality and new disturbance features on patterns of grizzly bear seasonal home-range fidelity and drift by comparing consecutive-year seasonal home ranges. We relied on the geographic technique “spatial–temporal analysis of moving polygons” (STAMP) to examine changes in habitat quality and new development between zones of home-range fidelity, expansion, and contraction. Areas considered to be high-quality habitat were selected at a greater frequency than available and retained in zones of home-range fidelity, but also vacated during home-range contraction. Areas of decreasing habitat quality were equally present in zones of contraction, expansion, and stability. The proportion of new forest harvest areas and roads developed within the past year did not differ between zones of home-range change, but the proportion of new well sites was higher in contraction zones than in stability zones. Our results showed that while considerable drift occurs, changes in habitat quality and recent anthropogenic disturbances cannot account for annual variation in home ranges, suggesting other important factors influencing behaviour and movement.

Socio-spatial organization and spatial ecology

2017 ◽  
Author(s):  
M.G.L. Mills ◽  
M.E.J. Mills
Keyword(s):  
Home Range ◽  
Spatial Ecology ◽  
Spatial Organization ◽  
Scent Marking ◽  
Home Range Size ◽  
Dispersal Distance ◽  
Range Size ◽  
Home Ranges ◽  
Large Home Range ◽  
Core Areas

Home ranges of males (1204 km2) and females (1510 km2) were similar. Female home range size was positively related to the dispersion of prey and generally, but not exclusively, they displayed home range fidelity. Overlap between female home ranges was extensive, although they rarely met up. Male home ranges overlapped extensively and there was no difference in size between coalition and single males. Males overcame the problem of scent marking a large home range by concentrating scent marks in core areas. Generally female cheetah home range size is affected by resource productivity, although where prey are migratory, or in fenced reserves where movements are constricted, and areas where disturbance is severe, this may be different. Southern Kalahari males apparently need large home ranges to increase the likelihood of locating wide-ranging and sporadically receptive females. Mean dispersal distance for subadult males (96 km) was further than for females (39 km).

Home Range, Dispersal and Density of Red Foxes (Vulpes Vulpes L.) In Central Victoria.

1991 ◽  
Vol 18 (2) ◽  
pp. 215 ◽  
Author(s):  
BJ Coman ◽  
J Robinson ◽  
C Beaumont
Keyword(s):  
Home Range ◽  
Radio Telemetry ◽  
Control Program ◽  
Total Sample ◽  
Home Range Size ◽  
Dispersal Distance ◽  
Breeding Pair ◽  
Home Ranges ◽  
Red Foxes ◽  
Central Victoria

Between 1983 and 1986, various aspects of red fox spatial behaviour were studied in both rural and semi-urban environments in central Victoria. Using radio-telemetry, the short-term home ranges of three adult foxes (2 male, 1 female) in a pasture/woodland habitat were estimated to be of the order of 5-7 km2 each. In a semi-urban environment nearby, the home ranges of a further 3 adult animals (2 male, 1 female) were estimated to be 0.6-1.3 km2 each. Estimates of home range size based on a 90% space utilisation effectively halved the home range area for all six foxes. There were indications that, for the animals concerned, ranges were mutually exclusive except in the case of a breeding pair which shared a common home range. During the studies, 137 young fox cubs were ear-tagged and released at the point of capture. Subsequently, 46 of these animals were returned by hunters. Nearly 70% of the returned animals were killed at a distance of 2 km or less from the tagging site but dispersal distances of up to 30 km were recorded. The average dispersal distance for animals killed more than 2 km from the tagging site was 11 km. Estimates of fox density in a rural area of some 2400 ha were obtained by a survey of active breeding dens in the 1985 and 1986 breeding seasons. Assuming one breeding pair plus three surviving young per litter, the maximum summer density was estimated at about 3.0 foxes km-2 and the minimum winter density as about 1.2 foxes km-2. For a further estimate of density, 13 foxes were live-captured, fitted with radios and released. In a short control program on the study area a few weeks later, 7 of these animals were recovered in a total sample of 50 foxes killed. The remaining 6 foxes were established as still present in the study area. Using this capturehecapture data, an early autumn density of about 3.9 foxes km-2 was indicated. The significance of this data in relation to the possible role of foxes as vectors of rabies disease in Australia is discussed.

scholarly journals Home range and habitat selection of captive-bred and rehabilitated cape vultures Gyps coprotheres in southern Africa

Oryx ◽  
2020 ◽  
pp. 1-6
Author(s):  
Ben Jobson ◽  
Kerri Wolter ◽  
Lara Jordan ◽  
Ara Monadjem ◽  
J. Marcus Rowcliffe
Keyword(s):  
Habitat Selection ◽  
Home Range ◽  
Southern Africa ◽  
Spatial Ecology ◽  
Captive Breeding ◽  
Release Site ◽  
Home Range Size ◽  
Selection Strategy ◽  
Home Ranges ◽  
The 1960S

Abstract Following the continual decline of the Cape vulture Gyps coprotheres since the 1960s, captive breeding and rehabilitation programmes have been established to reinforce populations across southern Africa. This study examines the spatial ecology of captive-bred and rehabilitated vultures following release. Our analysis used 253,671 GPS fixes from 20 captive-bred and 13 rehabilitated birds to calculate home range sizes using kernel density estimation. We found that home range size did not differ significantly between captive-bred and rehabilitated birds. The location of home ranges differed: captive-bred birds showed greater site fidelity, remaining close to their release site, whereas rehabilitated birds dispersed more widely across the species' native range. By remaining close to their release site within a protected area, captive-bred birds had a significantly higher per cent of their GPS fixes within protected areas than did rehabilitated birds. Despite fidelity to their release site, captive-bred birds demonstrated innate capabilities for natural foraging behaviours and the same habitat selection strategy as rehabilitated individuals. These findings suggest that captive breeding and reinforcement of populations at declining colonies could provide localized benefits. Future long-term studies should seek to analyse survivorship and identify the breeding behaviour of these captive-bred birds once they reach sexual maturity.

scholarly journals Home ranges, habitat and body mass: simple correlates of home range size in ungulates

2016 ◽  
Vol 283 (1845) ◽  
pp. 20161234 ◽  
Author(s):  
Endre Grüner Ofstad ◽  
Ivar Herfindal ◽  
Erling Johan Solberg ◽  
Bernt-Erik Sæther
Keyword(s):  
Home Range ◽  
Spatial Scale ◽  
Body Mass ◽  
Group Size ◽  
Animal Movement ◽  
Meta Analysis ◽  
Habitat Type ◽  
Home Range Size ◽  
Range Size ◽  
Home Ranges

The spatial scale of animal space use, e.g. measured as individual home range size, is a key trait with important implications for ecological and evolutionary processes as well as management and conservation of populations and ecosystems. Explaining variation in home range size has therefore received great attention in ecological research. However, few studies have examined multiple hypotheses simultaneously, which is important provided the complex interactions between life history, social system and behaviour. Here, we review previous studies on home range size in ungulates, supplementing with a meta-analysis, to assess how differences in habitat use and species characteristics affect the relationship between body mass and home range size. Habitat type was the main factor explaining interspecific differences in home range size after accounting for species body mass and group size. Species using open habitats had larger home ranges for a given body mass than species using closed habitats, whereas species in open habitats showed a much weaker allometric relationship compared with species living in closed habitats. We found no support for relationships between home range size and species diet or mating system, or any sexual differences. These patterns suggest that the spatial scale of animal movement mainly is a combined effect of body mass, group size and the landscape structure. Accordingly, landscape management must acknowledge the influence of spatial distribution of habitat types on animal behaviour to ensure natural processes affecting demography and viability of ungulate populations.

scholarly journals Use of Space by Black-and-Gold Howler Monkeys (Alouatta caraya) in an Urban Environment in Paraguay.

2022 ◽  
Author(s):  
Xander Duffy ◽  
Jake Wellian ◽  
Rebecca L. Smith
Keyword(s):  
Home Range ◽  
Urban Environment ◽  
Group Size ◽  
Home Range Size ◽  
Range Size ◽  
Howler Monkey ◽  
Home Ranges ◽  
Alouatta Caraya ◽  
Minimum Convex Polygon ◽  
Core Areas

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.

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