Context. Given the immense impact of wildlife trade, disease and repatriations on populations, health assessments can provide powerful forensic material to help convict wildlife poachers and minimise risks of releasing unhealthy wildlife.

Aims. We aimed to use reference ranges to assess the health of confiscated tortoises, to illustrate forensic application of these ranges, and to advance analyses for future applications.

Methods. We used analyses of variance (ANOVA) and covariance (ANCOVA), and composite indices, to compare wild and confiscate tortoise body condition, haematocrit and haemoglobin concentration of males and females of three tortoise species. Subsequently, we used multivariate statistics (e.g. discriminant analyses) to evaluate the relative importance of species, sex and group (wild or confiscate) on tortoise condition and haematology.

Key results. Our initial statistical tests demonstrated, at P < 0.05 to P < 0.0005, that confiscate body condition and haematology were compromised compared with that of wild tortoises. Subsequently, discriminant analyses strongly discriminated between most wild and confiscate groups (P < 0.0001), correctly classified individual health as wild or confiscate 80–90% of the time, indicated that species and sex effects were stronger than was the wild-confiscate category, and provided discriminant functions for use on other taxa and studies.

Conclusions. The health assessments discriminated well between wild and confiscate tortoises. The results had considerable forensic value, being relevant, quickly generated using portable field equipment, reliable, accurate, easy to explain and convey in terms of likelihood in a court of law, synergistically consistent among variables and groups, a strong rebuttal to the poachers’ specific statements, and consistent with other types of evidence. Multivariate analyses were consistent with, and more prudent and powerful than, the original statistical analyses. Discriminant functions can be applied in future studies and on other chelonian species, and should be developed for other wildlife species.

Implications. Reference ranges provide considerable value for forensics, diagnostics and treatment. Given the disease risks resulting from the massive scale of wildlife trade and release, reference ranges should be developed for more species.

Context.Efficiency of large-scale capture–mark–recapture (CMR) studies can be improved by developing accurate methods for predicting the window of opportunity in which banding can occur.

Aims.This research aimed to investigate potential efficiency improvements in a long-term CMR raptor study. The research focussed on: (1) developing selection processes for adopting CMR protocols; (2) testing methods for increasing the number of nestlings successfully banded; and (3) assessing the efficacy of visual identification (VID) bands for collecting re-sight data.

Methods.Ten selection criteria were developed into a robust CMR-technique selection process and used to assess marking techniques commonly applied to birds. Optimising banding effort by predicting banding dates using two different techniques a priori and a posteriori were tested against a traditional approach to the timing of banding. The cost (in time) to collect resight data at an active nest site was also measured.

Key results.The CMR selection criteria and parameters provided a transparent selection process and scored metal VID bands the highest for the study design. This provided individual recognition of marked birds up to the expected life-span of 14 years. Both techniques for predicting banding dates improved the proportion of whole clutches banded by 40%. The average time to identify both peregrine falcon adults of a breeding pair wearing VID bands was 30 min.

Conclusions.The two methods described here for predicting preferred banding dates are of particular value as efficient approaches to banding large numbers of nestlings are key to the success of CMR studies. All of the methods developed in this research can be applied to CMR studies of almost any bird species with a predictable seasonal breeding system.

Implications.Optimisation and cost effectiveness of CMR studies for seasonal breeding birds can be significantly improved by accurately predicting the window of opportunity in which banding of nestlings can be carried out, and also utilising VID colour bands for rapid collection of recapture data.

Context. Many contraceptive agents have demonstrated effectiveness in wild species, most notably immunocontraceptives such as GnRH conjugates and porcine zona pellucida (PZP). The major challenge in using these agents to control deer and other wildlife populations in the field now lies with safe, effective and efficient delivery to a large-enough proportion of the population to suppress growth.

Aims. Because deer and other wildlife are typically difficult to access for treatment, contraceptives that require multiple or repeated treatments will be of limited management value. To address this constraint, we conducted a field study of white-tailed deer (Odocoileus virginianus) on Fripp Island, SC, USA, to test two different technologies for achieving single-administration, multi-year efficacy in PZP vaccines.

Methods. Between 2005 and 2010, we captured, ear-tagged and blood-sampled a total of 245 individual adult and yearling female deer. Deer were hand-injected at capture with one of two preparations of SpayVac or a combination native PZP–adjuvant emulsion plus PZP–adjuvant incorporated into lactide–glycolide polymer pellets engineered to release at 1, 3 and 12 months post-treatment. Pregnancy was determined from serum assays of pregnancy-specific protein B sampled from captured deer.

Key results. Aqueous SpayVac, and the PZP–adjuvant-containing polymer pellets manufactured through a heat extrusion (H/X) method administered simultaneously with PZP–AdjuVac or modified Freund’s complete adjuvant emulsions reduced pregnancy rates from control levels by 95–100% in the first year after treatment, and by 65–70% in the second year after treatment.

Conclusions. A single, hand-injected vaccination with SpayVac or PZP–adjuvant emulsion combined with H/X PZP pellets reduced fertility for multiple years.

Implications. Single-treatment, multi-year immunocontraceptive vaccines bring contraceptive management of wildlife populations one step closer. Future efforts should focus on improving handling and storage, developing technologies for remote delivery, and addressing remaining regulatory and management concerns.

Context . The estimation of alert (vigilance) and flight-initiation (escape) distances (AD and FID, respectively) has underpinned theoretical and applied studies of the escape behaviour and management of disturbance to wildlife. Many studies use multiple observers, and some conduct meta-analyses; these efforts assume no observer effects in the estimation of these distances.

Aims and methods . We compared the estimates of FID and AD under ideal conditions (i.e. of black swans, Cygnus atratus, a large species with obvious behaviour, and at a location where swans allowed close approaches in open habitats), by one experienced and four inexperienced observers.

Key results . FID did not differ among observers but AD differed between the experienced and all inexperienced observers, and among inexperienced observers. Thus, FID estimates appear more repeatable than those of AD. Experience apparently results in more conservative estimates of AD.

Conclusions . FID represents a repeatable measure that is consistent across observers. This study supports its broad application in the study of wildlife escape behaviour.

Implications . We recommend the use of FID rather than AD for comparative analyses that involve multiple observers, because FID is more reliably measured.

Context . Scatter-hoarding rodents tend to hoard plant seeds in preferred places that facilitate seed survival, resulting in high food rewards for hoarders and a high probability of seedling establishment for plants.

Aims . To test the hypothesis that caches placed in rodent-preferred microhabitats, nearest-neighbour distances between caches (cache density) or cache depths have an increased chance of survival.

Methods . Rodent-made caches and observer-established caches of Himalayan hazelnut (Corylus ferox) seeds were tracked in a subtropical primary forest in central China. The survival of caches within rodent-preferred microhabitats, nearest-neighbour distances and cache depths were identified.

Key results . Rodents preferred to hoard Himalayan hazelnut seeds in microhabitats under and at the edge of shrubs, with the nearest-neighbour distance of <4.0 m, and at 2.1–4.0-cm depth. The survival times of both rodent-made caches and observer-established caches were longer within rodent-preferred microhabitats than in other habitats and increased with an increasing nearest-neighbour distance and cache depth, up to what appeared to be an optimal nearest-neighbour distance and depth.

Conclusions . Conditions of rodent-preferred cache microhabitats, nearest-neighbour distances and cache depths can facilitate cache survival.

Implications . Rodents often move plant seeds away from parent trees and bury them in shallow soil, which benefits seed dispersal and establishment of plants. The present study demonstrates that rodent-preferred cache conditions may translate into higher seed survival and a higher tendency of seeds to germinate and establish. Thus, careful management and conservation of rodent-preferred hoarding habitats may benefit seed dispersal and survival.

Context. The primary selective forces responsible for shaping life-history traits come from the physical and biological environment in which a species resides. Consequently, the limits of a species range may provide a useful measure of adaptive potential to environmental change. The proximity of foraging grounds to terrestrial nursing habitat constrains central-place foragers such as otariid seals in selecting breeding locations. The Australian sea lion (Neophoca cinerea) is an endangered otariid endemic to Australia, whose northern-range extent occurs at a temperate–tropical transition zone on the western coast of Western Australia (WA).

Aims. Currently, there is a complete absence of data on the foraging ecology of Australian sea lions in WA. We sought to address this critical knowledge gap and provide data on the foraging ecology of adult female Australian sea lions at three isolated breeding colonies in western WA.

Methods. We used stable-isotope ratios of carbon (δ¹³C) and nitrogen (δ¹⁵N) in the whiskers of pups as proxies to characterise feeding behaviour of 10–28% of all adult female Australian sea lions at each colony. We then compared these geographic data to (1) conspecifics at similar latitude in South Australia (SA) and (2) isotopic data collated from other studies on seabirds that inhabit the region, to place foraging behaviour of adult female Australian sea lions into context.

Key results. At the southernmost colonies in WA, individual animals were members of one of two distinct isotopic clusters that could be described by differences in δ¹⁵N and δ¹³C values. Individuals at the northernmost colony displayed δ¹⁵N values similar to those of seabirds in the same region. Across the study, isotope ratios of adult female Australian sea lions in western WA were between 3‰ and 5‰ lower than those observed at a colony at similar latitude in SA.

Conclusions. Gross differences in the physical oceanography between WA and SA may in part explain the differences in isotope ratios of individuals between the regions, with lower δ¹⁵N and δ¹³C values in WA probably reflecting the relatively depauperate conditions of the Leeuwin Current.

Implications. Potential regional differences in trophic structure should be considered when developing appropriate management plans for Australian sea lions and regional variation in the diet of Australian sea lion warrants further investigation.

Context . Spread of the invasive cane toad (Rhinella marina) across northern Australia is of concern. Predator species, including the freshwater crocodile (Crocodylus johnstoni), are susceptible to cane toad toxins when ingested. Upstream populations of freshwater crocodiles are smaller than downstream counterparts because of limited resources. We measured the impact of cane toad arrival on densities of these upstream populations.

Aims . Our aim was to determine whether the influx of cane toads had a negative impact on populations of upstream ‘stunted’ freshwater crocodiles.

Methods . Population surveys for crocodiles were conducted in three upstream creek systems, using day- and night-based survey methods, before the arrival of cane toads in the area. These surveys were repeated under similar conditions following the arrival of cane toads, to compare the distribution and densities of freshwater crocodiles and, hence, measure the impact of cane toads.

Key results . There were significant declines in crocodile density at two survey sites following the arrival of cane toads, and we found dead crocodiles and cane toad carcasses with crocodile bite marks. The third site showed no change in density. There was a decline in mean density across all sites from 3.0 crocodiles km^–1 to 1.1 crocodiles km^–1 following the arrival of cane toads.

Conclusions . There was an overall decrease in crocodile densities and a reduction in distribution following the arrival of cane toads into the survey area. Dead crocodiles and evidence of their having eaten cane toads strongly suggest that these declines were caused directly by the arrival of cane toads into the area. One site showed no apparent change other than an increase in wariness, which may reflect the distribution of available feeding and shelter resources among the three sites.

Implications . These results suggest that upstream freshwater crocodile populations are highly susceptible to cane toad toxins, and that impacts on their population can include local extirpation. Considering their morphological and possibly genetic distinctiveness, the loss of these unique populations is of conservation concern.

Context. Maternity roosts of insectivorous bats (where females raise young) are critical to the conservation of threatened species as roost quality can influence reproductive success. Additionally, threatened species may have specialised requirements or unusual behaviour, which may be overlooked without targeted investigation.

Aims. To explore which factors influence the roost selection of Mormopterus norfolkensis, by comparing day roosts, identified via radio-tracking, with environmental variables collected at tree, patch and landscape scales.

Methods. We collected a range of variables describing maternity roosts and surrounding patches, including internal measurements of hollows and microclimate. Additionally, we derived landscape-scale variables using a geographic information system. We then explored which variables best explained roost occurrence using logistic regression.

Key results. Nineteen lactating females and two male M. norfolkensis were tracked to 40 roost trees, mostly grey mangrove, Avicennia marina subsp. australasica. Lactating females were found to be faithful to two patches of mangrove forest close to where they were captured, regularly switched roosts and roosted in hollows singularly or in small groups. The attributes of mangrove patches, especially a high proportion of hollows, better predicted roosting by lactating females than roost-tree or landscape characteristics. Additionally, although the microclimate of roost hollows was not significantly different from ambient mangrove conditions, the mangrove forest was slightly more stable and had higher humidity than did other nearby habitats.

Conclusions. Contrary to predictions, maternity roosting group sizes were relatively small, indicating that bats were not deriving thermoregulatory benefits from communal living. However, we suggest that lactating females may benefit from the operation of a fission–fusion society among the colony as a whole. Additionally, the mature mangrove forest could offer unique roosting opportunities for bats because they support high densities of hollow-bearing trees, a stable microclimate and potentially low abundances of predators and competitors.

Implications. This is one of few international bat–mangrove studies and it illustrates that threatened species can behave unexpectedly and may be overlooked in conservation strategies that are based largely on anecdotal observations. We encourage further research into the value of mangrove forests to terrestrial fauna globally.

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.

Context. In Spain, the release of farm-reared partridges to hunt is increasingly used, despite being thought to affect sustainability of wild stocks and to reduce the need of natural habitats for game.

Aims. To explore the market value as a possible incentive for current management, we evaluated within a segment of the red-legged partridge hunting market whether the use of farm-reared birds (as opposed to wild stock) or the naturalisation of landscapes are affecting the hunt market price.

Methods. We considered estates that sell individual hunting days and contacted buyers through advertisements. We gathered all advertisements for the 2010 season in four top hunting magazines and two websites, and conducted a telephone survey to record price and associated characteristics of hunts. We looked for relationships between price and the characteristics of sold hunts, using general linear models.

Key results. Hunts varied largely in price, but neither restocking nor naturalisation of the landscape explained price variation, at least within our sample of estates. The absence of price difference between wild or released partridges could be reflecting the current difficulty to distinguish both kinds of products in the market.

Conclusions. Market forces alone might not be promoting the public interest of the sustainable use of wild stocks versus industrial hunting based on farm-reared birds.

Implications. If promoting conservation and sustainable use of wild stocks is considered a major goal of official institutions in charge of biodiversity conservation and game management, they should promote reliable ways of identifying estates selling wild or restocked partridges, and they should also evaluate benefits and costs associated with hunting farm-reared birds relative to wild birds, so as to help internalise these costs and benefits if necessary. A study of the determinants of hunter demands would also help explain variation in supply and market prices.