Release-site Fidelity Research Articles

Assessing the success of the first cheetah reintroduction in Malawi

AbstractIn an effort to restore parts of their historical geographical range, and in recognition of their ability to restore ecosystem functioning and of the financial benefits they can provide through ecotourism, large carnivores have been reintroduced in many protected areas from which they were previously extirpated. Similar to dispersing animals, translocated individuals often undertake long-distance exploratory movements before establishing home ranges. Post-release monitoring of reintroduced carnivores is common, but the mechanisms of population establishment are rarely examined, limiting our understanding of reintroduction success. We monitored survival and post-release movements of seven cheetahs Acinonyx jubatus reintroduced to Liwonde National Park, Malawi, to evaluate early population establishment. Exploratory phases post-release lasted 29–174 days. Duration of pre-release holding periods in the boma had no significant effect on daily distance moved. Males travelled significantly farther and established home ranges later than females. All cheetahs showed release site fidelity and all females birthed their first litter within 4 months of release. Within 2 years of reintroduction, the newly established population consisted of 14 cheetahs, with demographic attributes similar to those recorded in the source populations. Based on individual settlement, survival and reproduction rates, we deemed this reintroduction successful in re-establishing a breeding population of cheetahs in Liwonde. Our findings suggest the drivers of settlement and population establishment for reintroduced cheetahs are complex, highlighting the importance of assessing and reporting post-release monitoring data.

Movement, spatial ecology, and habitat selection of translocated Gould's wild turkeys

AbstractTranslocations have aided restoration of wild turkeys (Meleagris gallopavo) across North America and are used to help establish sustainable, local populations even now. Because successful restocking relies on individuals remaining close to the release site to reduce movement‐based mortalities, a close examination of behaviors and factors affecting site selection can improve survival of translocated birds and enhance translocation success. Therefore, we assessed movements and habitat selection following translocation of 16 Gould's wild turkeys (M. g. mexicana) radiotagged with GPS‐VHF transmitters in Arizona. We assessed daily distance traveled, range size, distance from release site, and habitat selection from release to 120 days post‐release. Turkeys increased space use ~35 days post‐release. After 70 days post‐release, individuals shifted their behaviors to exploitation and individual maintenance, which was characterized by decreasing movements and space use. Turkeys had high release site fidelity and remained 1,352.2 ± 318.7 m (x̄ ± SE) from the release site 120 days post‐release. Distance between daily roost sites stabilized around day 50, and turkeys were within 89.8 ± 49.9 m (x̄ ± SE) of the previous night's roosting site by day 120. Gould's wild turkeys selected for riparian areas throughout the study period and selected for pine (Pinus spp.)‐juniper (Juniperus spp.) woodland for the first 60 days post‐release; thereafter pine‐juniper woodland was used in proportion to availability. Gould's wild turkeys used open‐herbaceous areas and pine–oak (Quercus spp.) woodland in proportion to availability. Our results indicate that Gould's wild turkeys take about 70 days to integrate into a new local environment following translocation, and riparian areas are a critical component of Gould's wild turkey habitat within the southwestern United States. Managers should ensure riparian areas are protected and restored before translocating Gould's wild turkeys to facilitate translocation success and persistence of Gould's wild turkey populations.

Habitat utilization and release-site fidelity of translocated captive-bred giant pandas (Ailuropoda melanoleuca)

The behavioural adaptation (movement and habitat utilization) of translocated organisms to a new environment after their release is crucial in translocation programs because it may affect survival. Therefore, identifying the factors determining habitat selection by the relocated animals is essential to improving the planning and the outcome of such programs. Using the data from three relocated giant pandas (Ailuropoda melanoleuca), we studied the habitat utilization, release-site fidelity, and interaction with resident giant pandas. The results showed that the quality of habitat used by the relocated giant pandas was significantly higher than the average habitat quality of the research region, and was significantly lower than that used by resident giant pandas. This suggested that the released three giant pandas had habitat selection abilities. The three released giant pandas gradually moved away from their release sites and did not exhibit site fidelity. In the first six months, the giant pandas stayed within about 3 km of their release sites, where habitat was good quality but overlapped with the distribution of resident giant pandas. The overlap of location between released and resident giant pandas decreased after six months when the released giant pandas moved away from their release sites.

Big Cats Return to Majete Wildlife Reserve, Malawi: Evaluating Reintroduction Success

Large carnivores are frequently reintroduced into protected areas to compensate for anthropogenic-driven losses. The lack of post-release monitoring has impeded our knowledge on how these carnivores adapt to their new environment, which often results in uncertainty of whether or not reintroductions were successful. Between 2011 and 2012, six leopards (Panthera pardus) and three lions (Panthera leo) were reintroduced into Majete Wildlife Reserve, Malawi, and each animal was fitted with a GPS or VHF collar to monitor their post-release movements and behaviour. All individuals survived longer than two and a half years post-release and successful breeding events were recorded for all females, except one leopard. Released felids showed little initial exploratory behaviour, none homed to their capture location and all individuals displayed at least some degree of release site fidelity. Lions established permanent ranges between five and seven months after release, with a mean home range of 82.1km2 (95%, T-LoCoH). Three leopards established permanent ranges between four and eight months, with a mean home range of 181.6 km2 (95%; T-LoCoH). Two leopards did not establish fixed home ranges, but rather exhibited continuous shifts in range which were likely due to natural disruptive events such as season, prey availability and other competitors. Our findings suggest that reintroduced felids may take longer to establish permanent home ranges than previously thought, highlighting the importance of long-term post-release monitoring. Based on our study, reintroduction appears to be an effective and viable tool to restore large carnivores in protected areas in Malawi.

Initial Movements of Re- introduced Elk in the Missouri Ozarks

Initial movements of re- introduced wildlife populations can determine short-term restoration success. Managers need ways to encourage release site fidelity to mitigate suboptimal breeding, reduce mortality rates, and minimize human-wildlife conflicts. We studied initial movement ecology of elk (Cervus elaphus) fitted with GPS collars and re- introduced to the Missouri Ozarks in 2011 (n = 32), 2012 (n = 21), and 2013 (n = 31) for 6 mo post release. We assessed maximum displacement from the release site, range shifts, and range size across four sequential time frames (0–10 d, 11–31 d, 32–61 d, and 62–183 d). Compared to other elk restorations in eastern North America, site fidelity was high, with maximum distance from the release site 62–183 d post release ≤10 km for 94% of 2011 animals, 57% of 2012 animals, and 97% of 2013 animals. Elk range sizes were similar during the first 61 d post release but doubled in size 62–183 d post release to an average of 26.2 km2 (range: 4.0–218.8 km2). The average range overlap for individual elk in sequential time periods was between 23–26% across years, indicating elk used different areas over time. Release site had the greatest influence on initial movements; one site used in 2012 was associated with greater release site displacement and range sizes. Maternal cows also demonstrated higher site fidelity to the release site than nonmaternal cows. High site fidelity and small home ranges in elk recently restored to Missouri may be attributed to soft release, minimal human disturbance, quality habitat, and release groups of mature females.

Comparative migration strategies of wild and captive‐bred Asian Houbara Chlamydotis macqueenii

For migratory species, the success of population reintroduction or reinforcement through captive‐bred released individuals depends on survivors undertaking appropriate migrations. We assess whether captive‐bred Asian Houbara Chlamydotis macqueenii from a breeding programme established with locally sourced individuals and released into suitable habitat during spring or summer undertake similar migrations to those of wild birds. Using satellite telemetry, we compare the migrations of 29 captive‐bred juveniles, 10 wild juveniles and 39 wild adults (including three birds first tracked as juveniles), examining migratory propensity (proportion migrating), timing, direction, stopover duration and frequency, efficiency (route deviation), and wintering and breeding season locations. Captive‐bred birds initiated autumn migration an average of 20.6 (±4.6 se) days later and wintered 470.8 km (±76.4) closer to the breeding grounds, mainly in Turkmenistan, northern Iran and Afghanistan, than wild birds, which migrated 1217.8 km (±76.4), predominantly wintering in southern Iran and Pakistan (juveniles and adults were similar). Wintering locations of four surviving captive‐bred birds were similar in subsequent years (median distance to first wintering site = 70.8 km, range 6.56–221.6 km), suggesting that individual captive‐bred birds (but not necessarily their progeny) remain faithful to their first wintering latitude. The migratory performance of captive‐bred birds was otherwise similar to that of wild juveniles. Although the long‐term fitness consequences for captive‐bred birds establishing wintering sites at the northern edge of those occupied by wild birds remain to be quantified, it is clear that the pattern of wild migrations established by long‐term selection is not replicated. If the shorter migration distance of young captive‐bred birds has a physiological rather than a genetic basis, then their progeny may still exhibit wild‐type migration. However, as there is a considerable genetic component to migration, captive breeding management must respect migratory population structure as well as natal and release‐site fidelity.

Cheetahs (Acinonyx jubatus) running the gauntlet: an evaluation of translocations into free-range environments in Namibia.

Following dramatic range and population declines, the cheetah is Africa’s most endangered large felid. In Namibia, private land managers still trap cheetahs but increasingly consider moving animals instead of killing them. Across Africa, managers have translocated perceived conflict carnivores for decades, but rarely evaluated their actions. We analyse the outcomes of 15 cheetah translocations (for 23 adults and 10 dependent offspring) into free-range environments in Namibia. We released cheetahs at an average distance of 419.6 km ± 216.1 km SD (range: 71–816 km) after captive periods ranging from 1–1,184 days (350.6 days ± 439.0 days SD). An individual’s ability to survive the first year predominantly determined the overall translocation success of 40%. Post-release conflict and homing had less impact on success. Cheetah survival was lowest in the first three months after release. Human persecution (50% of deaths) and spotted hyaenas (29% of deaths) had the highest effect on survival. The degree of habituation to humans acquired during captivity significantly influenced chances of survival. Cheetahs surviving the initial post-release period (∼90 days) often settled into ranges and females reproduced successfully. However, all individuals exhibited extensive movements, frequently roaming >4,000 km2 in the first six months after release (with a maximum of 19,743 km2 in 112 days), resulting in low release site fidelity. Soft release and larger recipient area size did not improve site fidelity. Based on these outcomes, we evaluated which unfenced conservation areas in Namibia could potentially receive cheetahs. We found that there are currently few public and/or private reserves large enough to contain the movement profiles we observed in this study. This suggests that most translocations will result in cheetahs re-entering farmlands where they face a high risk of persecution. In conclusion, translocations into unconfined areas can successfully conserve individual cheetahs. Due to high mortality and unpredictable outcomes, however, conservation efforts need to focus on improving tolerance of cheetahs in commercial livestock and game farming areas in order to reduce the number of indiscriminately trapped animals.

Using the movement patterns of reintroduced animals to improve reintroduction success

Abstract Despite their importance to conservation, reintroductions are still a risky endeavor and tend to fail, highlighting the need for more efficient post-release monitoring techniques. Reintroduced animals are released into unfamiliar novel environments and must explore their surroundings to gain knowledge in order to survive. According to theory, knowledge gain should be followed by subsequent changes to the animal’s movement behavior, making movement behavior an excellent indicator of reintroduction progress. We aim to conceptually describe a logical process that will enable the inclusion of behavior (in particular, movement behavior) in management decision-making post-reintroductions, and to do so, we provide four basic components that a manager should look for in the behaviors of released animals. The suggested components are release-site fidelity, recurring locations, proximity to other individuals, and individual variation in movement behavior. These components are by no means the only possible ones available to a manager, but they provide an efficient tool to understanding animals’ decision-making based on ecological theory; namely, the exploration-exploitation trade-off that released animals go through, and which underlies their behavior. We demonstrate our conceptual approach using data from two ungulate species reintroduced in Israel: the Persian fallow deer Dama mesopotamica and the Arabian oryx Oryx leucoryx [Current Zoology 60 (4): 515–526, 2014].

Is there really no place like home? Movement, site fidelity, and survival probability of translocated and resident turtles

Wildlife translocations, the deliberate movement of wild individuals from one part of their distribution to another, are increasingly being used as a conservation tool. Despite the popularity of translocations as a conservation technique, translocations are often not successful as a result of excessive movement, poor release site fidelity, and low survival. This study compares the movement patterns, site fidelity, and survival probability of resident and hard-released musk turtles (Sternotherus odoratus) in a complex of patchy distributed wetlands. Our results are different from most translocation studies as the majority of translocated turtles had movement (minimum convex polygon area, total distance moved, number of wetlands used, and the number of movement shifts between wetlands), release site fidelity, and wetland fidelity patterns that were similar to resident turtles. In addition, the survival probabilities of resident and translocated turtles were both high. We believe the combination of poor overland movement capabilities and the patchy distribution of wetlands surrounded by a strong boundary matrix of terrestrial habitat, potentially increased the costs of leaving the wetland. The high costs of travelling overland to more distant wetlands may have constrained the translocated turtles dispersal from the release site and increased release site fidelity. Our study suggests that hard-release translocations may be an effective conservation method for highly aquatic species unlikely to leave the wetland and travel long overland distances.

There is no place like home: high homing rate and increased mortality after translocation of a small mammal

Animal translocation is a popular tool in wildlife management. It is frequently used to solve human–animal conflicts and recently has been applied as a mitigation tool when animals inhabit land desired for development. However, its success is uncertain and involves risks. In order to provide useful information to wildlife managers about the effect of translocation distance on animal movement behavior and survival, we translocated 40 Long-haired field mice (Abrothrix longipilis) at different distances from their territories (0–1,300 m) in central Chile and recorded the location and survival of each mouse over 3 days. Translocated animals showed low release site fidelity and traveled two- to four-fold longer distances than the nontranslocated group. Only mice translocated at shorter distances (100 m) oriented their movement toward their origin site and had a high probability of homing (80 %). There were threshold distances from after which homing and traveling strongly decreased. All individuals released close to their capture site (≤100 m) remained alive, while mortality reached 22 % at longer translocation distances, principally as a result of fighting between rodents. Therefore, long translocation distances prevented short-term homing and decreased traveled distances (a desirable outcome), but risks associated with conspecific encounters need to be avoided. Because mice showed a high motivation to explore surroundings, it is advisable to release animals in sites with alternative places to colonize. Our results emphasize the need for a strong justification in wildlife translocation projects and the development of alternative techniques to improve animal welfare and conservation.

Within-stream release-site fidelity of steelhead trout from Lake Erie hatchery stocks

Straying of salmonids in Lake Erie is not well understood despite the economic importance of these recreational fisheries, which are sustained by stocking approximately 2million steelhead trout (Oncorhynchus mykiss) yearlings annually. The occurrence of straying in hatchery-reared salmonid populations can be influenced by stocking strategies, such as within-stream stocking location. Conneaut Creek provides a unique opportunity to evaluate the extent of release-site fidelity of adult steelhead trout from Lake Erie, because it is equally stocked by Ohio and Pennsylvania at different distances from the stream mouth. Adult steelhead trout were collected from two Conneaut Creek sites, Conneaut Ohio (2km from Lake Erie) and Albion Pennsylvania (61km from Lake Erie), in spring and fall of 2009. Elemental signatures of yearling otoliths measured by laser-ablation-inductively-coupled-plasma-mass-spectrometry were used to identify hatchery stocks. The state-specific hatchery stocks were identified with high confidence using discriminant analysis (Sr and Ba concentrations in nine otolith regions; Ohio 100.0%, Michigan 86.1%, New York 92.4%, and Pennsylvania 93.2% using jackknifed mean correct assignment). Adult steelhead trout (N=174) collected in spring and fall at Conneaut Ohio included both Ohio and Pennsylvania-stocked fish, but no Ohio-stocked steelhead trout were collected at the Pennsylvania site in either season. Of the classified adult steelhead trout, 13.8% were identified as strays from other states (New York and Michigan). These results confirm strong release-site fidelity between Ohio and Pennsylvania stocked steelhead trout and provides fishery managers with sound scientific data to refine their stocking practices.

Conservation of the Eurasian beaver Castor fiber: an olfactory perspective

Chemical communication in mammals includes an array of specific behaviours that are often ignored in terms of their potential relevance to conservation. Often used during territorial or social interactions between animals, chemical communication can also be used as a tool in reintroduction programmes. Reintroductions still exhibit high failure rates and methods to improve success should be investigated. The Eurasian beaver Castor fiber has been widely reintroduced across Europe after its near extinction in the 19th century. 2. Using olfactory studies in the beaver, we aim to demonstrate how scent transfers a range of information about the sender which can be used to monitor social and territorial behaviour along with general well-being. Scent manipulation can be used to reduce human-beaver conflicts, and aid reintroduction success through reducing stress and territorial conflicts, and by influencing dispersal and settlement. 3. Two species of beavers, the Eurasian beaver and the North American beaver Castor canadensis, occupy freshwater habitats throughout North America and in parts of South America, most of Europe and parts of Asia. Most of the reviewed literature concerns the wild Eurasian beaver, its chemical communication and con- servation; however, captive studies and those addressing North American beavers are also included. 4. Chemical communication is advanced and has been well documented in this highly territorial species. However, few studies directly link olfaction with conserva- tion practices. 5. Olfactory studies in beavers can provide non-invasive methods to monitor translocated animals and indicators of health. We conclude that chemical analysis, olfactory studies and behavioural manipulations involving semiochemicals have important impacts on conservation and can generate practical solutions to conser- vation problems including aiding animal capture, captive stress reduction, breeding pair formation and release site fidelity.

Is translocation of stock-raiding leopards into a protected area with resident conspecifics an effective management tool?

ContextTranslocation as a non-lethal management tool to eliminate individual ‘problem’ animals is commonly used but rarely evaluated. AimWe sought to evaluate whether translocating stock-raiding leopards (Panthera pardus) into a protected area with resident conspecifics in Botswana is effective in dealing with ‘problem’ carnivores. MethodsWe assessed release-site fidelity, ranging behaviour, individual survival and reduction of conflict after translocation of four translocated leopards in relation to four resident conspecifics, which were tracked from 24 days up to 4 years. Key resultsNone of the translocated leopards showed release-site fidelity; they either returned to the trap site or showed extensive roaming behaviour after release. Three of the four translocated leopards reportedly resumed stock-raiding and were shot when ranging outside of protected areas, which apparently was a consequence of being released into an area already occupied by territorial conspecifics. On the basis of satellite telemetry, the linear movement distance of one translocated leopard (1249 km) and the range size of three resident female leopards (513 ± 124 km2) are the largest on record. ConclusionsFrom comparing the survival and ranging behaviour of translocated leopards with that of resident conspecifics, we conclude that translocation was not an effective management tool for dealing with stock-raiding leopards in our study. ImplicationsRather than translocating ‘problem’ carnivores, efforts should focus on reducing the potential for problems to develop, most importantly on improving livestock-husbandry practices.

Mobility decisions and the predation risks of reintroduction

Predation is a common problem limiting the success of efforts to reintroduce vertebrates. Naı̈ve animals typically suffer high predation rates soon after release despite strong site fidelity in the first few days that would normally reduce predator encounter rates. However, recent theory predicts that low mobility can be associated with high concentrations of odour wastes that are attractive to predators, leading to low survival for individuals that move little. In this paper we test this model for captive-raised Microtus voles reintroduced into suitable habitat in western Finland where they are mainly hunted by chemo-sensing predators. Patterns in vole movement behaviour showed a humped relationship with time: animals moved little soon after release, then made exploratory movements from 3 to 6 days, which then subsided. Predation rates were highest in the first 3 days, with no vole mortalities occurring after voles began substantially moving beyond their release sites. Moreover, voles that survived the 3-week study period were more mobile than voles that were killed by scent-hunting predators, during the initial 3 days and during the final 3 days when voles also had lower mobility. These results suggest that the innate fear response of naı̈ve animals, which limit their movements in an unfamiliar environment, may be counterproductive when reduced mobility leads to waste accumulation that is attractive to potential predators. Consequently, pre-release conditioning of captive-raised individuals may need to consider methods to overcome initial release-site fidelity in order to enhance long-term survival prospects after reintroduction.