Context . Human activities can induce behavioural and stress responses in wild animals. Information is scarce on the effects of culling on anti-predator behaviour and endogenous stress response of wild ungulates.

Aims . In a Mediterranean area, we evaluated the effects of culling on vigilance, foraging and endogenous stress response of female fallow deer (Dama dama).

Methods . Effects of culling were evaluated through behavioural observations and hormone analyses of faecal samples.

Key results . In an area where culling occurred (C), individuals showed significantly greater vigilance rates and foraged closer to wood than in an area with no culling (NC). In C, 24 h after culling, faecal cortisol concentrations were greater than those recorded in NC, but they decreased significantly to values comparable to (48 h post-shot) and lower than (72 h post-shot) those observed in NC.

Conclusions . Most likely, culling determined behavioural responses in female fallow deer, but did not trigger long-term physiological effects.

Implications . Increased anti-predator behaviour may complicate the implementation of long-term culling programs.

Diagnosing the cause of a species’ decline is one of the most challenging tasks faced by conservation practitioners. For a species approaching extinction, it is not possible to go back in time to measure the agents that operated at various stages of the decline. Accordingly, managers are often restricted to measuring factors currently affecting residual populations, which may not be related to factors that operated earlier in the decline, and inferring other mechanisms from different lines of evidence. In this review, I adopt a methodical diagnostic framework to comprehensively evaluate the potential causal factors for the decline of the eastern quoll (Dasyurus viverrinus) in Tasmania, and propose a hypothesis as to the cause of decline. Potential causal agents were gleaned from two key sources: factors implicated in the eastern quoll’s historical demise on the Australian mainland, and factors that changed during the recent period of quoll decline in Tasmania. The three most likely candidate causal agents were investigated over 4 years to evaluate their likely contribution to the decline. Here, I synthesise the findings from this recent research to advance a hypothesis as to the cause of the eastern quoll decline in Tasmania. I suggest that a period of unsuitable weather reduced quoll populations to an unprecedented low abundance, and that populations are now too small to overcome established threat intensities to which they were robust when at higher densities. Residual small populations are inherently more susceptible to demographic, environmental and genetic stochasticity and are unlikely to recover without management intervention. I propose a study design to experimentally test this hypothesis, and outline priority areas for future research and actions to guide in the future management and conservation of the species. This case study illustrates an approach by which practical species conservation problems might be solved and recovery strategies may be better informed, thereby ensuring positive conservation outcomes for threatened species.

Context . Fertility control of females with levonorgestrel or deslorelin implants shows promise for managing populations of overabundant eastern grey kangaroos (Macropus giganteus). Although these implants have been tested separately in captive and free-ranging kangaroos, there has been no direct comparison under equivalent field conditions.

Aims . We investigated the long-term efficacy of levonorgestrel and deslorelin implants, together with the cost of treatment, ease of administration, and the welfare of the animals, in a side-by-side trial under realistic management conditions.

Methods . We captured 65 adult female kangaroos over 11 days at a golf course in Anglesea, Victoria, Australia. We assigned each female to one of the following three experimental groups: levonorgestrel (210 mg, n = 18), deslorelin (9.4 mg, n = 24) or procedural control (n = 23). We monitored reproductive success for 8 years, by observing young in the pouch in winter and spring.

Key results . Natural fertility was high; in most years, less than 20% of control females failed to reproduce. For deslorelin-treated females, the odds of failing to reproduce were four times higher than for the control group; for levonorgestrel-treated females, these odds were 74 times higher. Deslorelin was ineffective after 3 years, whereas levonorgestrel was effective for at least 5 years.

Conclusions . Levonorgestrel was markedly superior in efficacy, as shown by a stronger contraceptive effect persisting for longer. In other respects, the two implants were comparable, being similar in cost and ease of delivery, and equally safe.

Implications . Only levonorgestrel implants fulfill their promise for non-lethal, long-term control of kangaroo populations. Deslorelin implants cannot be recommended for this purpose.

Context . The Columbian sharp-tailed grouse (Tympanuchus phasianellus columbianus) is a subspecies of conservation concern in the western United States, currently occupying ≤10% of its historic range. Land and management agencies are employing translocation techniques to restore Columbian sharp-tailed grouse (CSTG) populations. However, establishing self-sustaining populations by translocating grouse often is unsuccessful, owing, in part, to low survivorship of translocated grouse following release.

Aims . We measured and modelled patterns of CSTG mortality for 150 days following translocation into historic range, to better understand patterns and causes of success or failure in conservation efforts to re-establish grouse populations.

Methods . We conducted two independent multi-year translocations and evaluated individual and temporal factors associated with CSTG survival up to 150 days following their release. Both translocations were reintroduction attempts in Nevada, USA, to establish viable populations of CSTG into their historic range.

Key results . We observed a clear temporal threshold in survival probability, with CSTG mortality substantially higher during the first 50 days following release than during the subsequent 100 days. Additionally, translocated yearling grouse exhibited higher overall survival (0.669 ± 0.062) than did adults (0.420 ± 0.052) across the 150-day period and higher survival than adults both before and after the 50-day temporal threshold.

Conclusions . Translocated CSTG are especially vulnerable to mortality for 50 days following release, whereas translocated yearling grouse are more resistant to mortality than are adult grouse. On the basis of the likelihood of survival, yearling CSTG are better candidates for population restoration through translocation than are adult grouse.

Implications . Management actions that ameliorate mortality factors for 50 days following translocation and translocations that employ yearling grouse will increase the likelihood of population establishment.

Worldwide, introduced vertebrate pests impact primary production, native biodiversity, and human health. In New Zealand, extensive pest control (∼10 million ha) is undertaken to protect native biota and to prevent losses to the primary sector from wildlife vectors of bovine tuberculosis (TB), primarily possums (Trichosurus vulpecula). Control is conducted by TBfree New Zealand and by conservation agencies. Remote, forested terrain is treated using the toxin 1080 via aerial delivery in bait with a return time of ∼5 years. Ground-based control is conducted annually using traps and/or poison bait. Possums are controlled to very low abundance by these operations. Aerial 1080 is effective against another forest-dwelling vertebrate pest, the ship rat (Rattus rattus). Possum control has reduced TB rates, but collateral benefits for native biodiversity have not been quantified, making it difficult to demonstrate a return on investment. We review information from 47 accounts of responses of native biota to possum control. Of these, 60% quantified responses to aerial 1080; the remainder were ground-based. Possum control benefited vegetation by increasing foliage and fruit production, and by reducing tree mortality. Controlling ship rats and possums together improved bird populations, but rats recovered rapidly and long-term outcomes for rat-vulnerable birds are unknown. Large-bodied invertebrates also benefited from extensive pest control. We conducted a meta-analysis of 84 response measures from 35 of these 47 studies in order to provide a quantitative assessment of these findings. The analysis demonstrated that both ground and aerial control of this invasive pest in New Zealand has provided substantial collateral benefits for native biota. Few studies have taken advantage of decades of extensive pest control in New Zealand to monitor ecosystem-level outcomes, which have received only short-term attention thus far. Non-treatment experimental controls and replicate sites that enable validated assessments of outcomes for native biota are vital. Future studies would benefit from a standardised set of biodiversity indicators from a range of taxonomic and functional groupings, and from standardising experimental designs so individual studies can contribute to future meta-analyses, to strengthen the evidence base for the impacts of invasive pests on native biota in New Zealand and worldwide.

Context . Diet selection is studied in herbivores using three predominant methods: (1) microhistological surveys (identification of plants cell walls remaining in gut contents or faecal excretions); (2) direct bite counts (of tame animals); and (3) indirect bite counts (identifying herbivory on damaged plant tissues). Microhistological surveys and direct bite counts are accurate and provide the potential advantage of linking diet selection to particular individuals. Also, they allow diet selection to be measured in systems with sympatric herbivores more easily than indirect bite counts. However, they require expertise in cell wall structure identification or access to tame animals, and generally require greater expense than indirect bite counts. Conversely, indirect bite counts have the advantages of relatively low cost and time commitment for gathering data and do not require animal observation, but may not be accurate.

Aims . We tested for similarity between diet-selection estimates calculated by indirect bite counts and microhistological surveys.

Methods . We performed concurrent indirect bite count and faecal microhistological surveys on white-tailed deer (Odocoileus virginianus) at Fort Bragg Military Installation, NC.

Key results . The indirect bite count survey assignment of selection was 48% similar to assignments derived from the microhistological survey, based on Jaccard’s similarity index. Out of 23 plant species determined to be selected by indirect bite counts, 15 of those species were selected according to microhistological surveys. According to the microhistological survey, eight of the selected plants made up 51% of the overall diet, and seven of those eight were selected according to the indirect bite counts.

Conclusions . Our data indicate that indirect bite counts may provide a relatively accurate index of the deer-selected plants most important in the white-tailed deer diet, but may be less appropriate to determine selection of plants that infrequently occur in their diet, plants that are typically consumed in entirety, or plants where herbivory damage is poorly identified.

Implications . Indirect bite counts are a relatively inexpensive and time-efficient tool that may be useful to determine plant species most important to white-tailed deer within a forested landscape, particularly if additional research can improve on associated inaccuracies.

Context . Shooting is used to reduce the abundance of kangaroo (Macropus sp.) populations in many peri-urban areas in Australia, but there is uncertainty surrounding the animal welfare outcomes of this practice.

Aim . We assessed the animal welfare outcomes of night shooting for peri-urban eastern grey kangaroos (Macropus giganteus). We quantified the duration of stress for: (1) shot animals; (2) euthanased pouch young; and (3) other animals in the same social group.

Methods . An independent observer collected thermal imagery data, enabling four key animal welfare parameters to be quantified: instantaneous death rate, median time to death, wounding rate and flight duration of conspecifics. The duration between pouch removal and insensibility was recorded for pouch young. Post-mortem data were recorded to confirm the location and extent of pathology from shooting.

Key results . Of the 136 kangaroos that were shot at, two were missed. The wounding rate was zero, with a 98% instantaneous death rate. The median time to death for the three animals not killed instantaneously was 12 s. For pouch young considered sentient, the median stress time was 4 s. Kaplan–Meier survival analysis revealed that the median flight duration of conspecifics was 5 s.

Conclusions . Our results indicate that night shooting produces a very short duration of stress to shot kangaroos, their pouch young and their conspecifics.

Implications . When compared to other wildlife shooting methods, night shooting is a humane method for culling peri-urban kangaroos.

Context . To create management strategies with the goal of sustaining a species such as Caucasian grouse (Lyrurus mlokosiewiczi), it is important to identify the habitat requirements of species, not just in terms of a correlation with a given habitat feature, but also the relationship between species presence and vegetation coverage, proximity to other habitat types, and importance at different spatial scales.

Aims . To predict the proportions and spatial configuration of major habitat types that are associated with high probabilities of Caucasian grouse lek occurrence.

Methods . Using minimum mapping-unit scale (i.e. grain) for land cover, we applied spatial analysis at three spatial extents (472-, 702- and 867-m-radius circles) to assess how the importance of different land-cover patterns and patch characteristics surrounding leks of Caucasian grouse changed with scale within the Arasbaran landscape (316.56 km²) in East Azerbaijan, Iran. A set of a priori models has been developed on the basis of landscape metrics linked to hypotheses that could explain the spatial pattern of Caucasian black habitat use at each scale. We used an information-theoretic approach based on Akaike’s information criterion (AIC) within a general additive models framework to model habitat selection, so as to compare the values of landscape metrics calculated for Caucasian grouse lek sites (n = 22) with those calculated for non-lek points (n = 44).

Key results . The probability of lek occurrence at each of the spatial scales increases with a larger amount of open, young forests in the landscape. At each scale, we could indicate the landscape composition and structure required to create an ideal habitat mosaic for Caucasian grouse. Such an ideal habitat mosaic within mountain forests of Arasbaran, for a 702-m-radius area around a potential lek site, would consist of non-square (i.e. more geometrically complex) patches of rangeland cover and deciduous stands with canopy cover of <50%, which encompass over 30% of landscape.

Conclusions . Our results identified differences in black grouse requirements at several scales within the landscape. We believe this will help managers improve the habitat focusing on the area around existing or inactive leks, to adapt the landscape to species requirements, and to encourage targeting new sites.

Implications . These findings demonstrated that not only can we identify important landscape requirements at a range of scales, but by characterising landscape composition and structure across these scales, forest managers can help prioritise combinations of habitats that best serve the conservation of the target species.