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Several conventional and recently available tools are available for an integrated control of European rabbits in Australia. We quantified the impact of the release of rabbit haemorrhagic disease virus K5 (RHDV K5, hereafter K5) and pindone (2‐pivalyl‐1,3‐indandione) baiting at 13 sites within Cudlee Creek fire scar in the Adelaide Hills, South Australia. K5 release was followed by pindone baiting between December 2021 and March 2022; the application of both control methods followed industry best practice. We counted rabbits using spotlights before and after the application of both control methods. Fly samples and livers from dead rabbits were collected to track K5 transmission within and between sites, and to detect the natural circulation of rabbit haemorrhagic disease virus 2 (RHDV2). K5 release had minimal impact on rabbit populations, with treated populations increasing by a mean of 65.5% at 14 days post‐release and 27.9% at 77 days post‐K5 release across all sites, comparable to the changes at control sites. K5 detection in flies up to 77 days post its release, and its detection in rabbit livers, demonstrates that it can survive and transmit in the environment for prolonged periods and that it can lethally infect some rabbits. This limited impact of K5 is consistent with previous studies and may be explained by pre‐existing RHDV/RHDV2 immunity in the target populations or the presence of young rabbits with natural innate RHDV immunity. The detection of K5 in flies from control sites demonstrates that it was vectored beyond its release location. A reduction in rabbit counts post‐pindone baiting was observed at most treatment sites, with a mean population reduction of 36.6% across all sites. Landholders need to carefully and strategically plan their integrated rabbit control programmes. Not all combinations of controls, even if theoretically logical, achieve meaningful outcomes for rabbit management. [ABSTRACT FROM AUTHOR]

Recent analyses of geographical variation in cats' diet across Australia have been used to highlight rabbit control as a conservation risk, on the basis that prey-switching by cats following rabbit control is likely to threaten Australian fauna. There is no direct evidence to support that proposition. However, there is direct evidence of repeated prey-switching due to seasonal fluctuations in uncontrolled rabbit populations, of long-term suppression of rabbit numbers by effective rabbit control, and that reduced rabbit abundance leads to reduced cat abundance, reduced predation of native fauna and recovery of threatened prey populations. Furthermore, rabbits are a known threat to many Australian native plants and rabbit control has proven benefits for their recovery, thereby offering long-term benefits for dependent fauna and broader ecosystem function. On the balance of evidence, rabbit control should be encouraged in Australia wherever possible, as a national conservation priority. [ABSTRACT FROM AUTHOR]

The European rabbit, Oryctolagus cuniculus, is threatened within its native range, yet it is a highly successful colonizing pest species across its worldwide introduced range, causing large economic losses and widespread environmental degradation. To date, there has been no long-term empirical evidence documenting the relative roles of climatic, epidemiological and biological factors in limiting life-history determinants of rabbit range and abundance. Using 12 years of capture-mark-recapture data from their exotic range in Australia, we constructed candidate Cormack-Jolly-Seber models to test the influence of environmental, competition and disease conditions on rabbit survival and recruitment. Our results show that: (i) population-level disease infection rate has the largest overall impact on rabbit survival, explaining 80% of variance in survival rates; (ii) environmental as well as epidemiological conditions constrain rabbit survival, especially for younger animals; (iii) temporal variation in rabbit kitten recruitment patterns are best described by a combination of climate, competition and disease settings (accounting for 68% of variance), while temperature alone has a strong negative influence on kitten recruitment; and (iv) recruitment responds positively to rabbit haemorrhagic disease, but negatively to myxomatosis - the former, probably being mediated through a disease driven effect on intraspecific competition for food. A strengthened understanding of climate change impacts on rabbit range and abundance can be achieved by accounting explicitly for potential synergisms between disease dynamics and climate. In this analysis, we provide the first step towards such an attempt for this important mammal species. Integrated approaches of this kind are essential for future forecasts of rabbit range and abundance, offsetting the conservation threat faced by O. cuniculus in its native range, and achieving effective management in exotic habitats. [ABSTRACT FROM AUTHOR]

1. A long-standing question in ecology is how natural populations respond to a changing environment. Emergent optimal foraging theory-based models for individual variation go beyond the population level and predict how its individuals would respond to disturbances that produce changes in resource availability. 2. Evaluating variations in resource use patterns at the intrapopulation level in wild populations under changing environmental conditions would allow to further advance in the research on foraging ecology and evolution by gaining a better idea of the underlying mechanisms explaining trophic diversity. 3. In this study, we use a large spatio-temporal scale data set (western continental Europe, 1968-2006) on the diet of Bonelli's Eagle Aquila fasciata breeding pairs to analyse the predator trophic responses at the intrapopulation level to a prey population crash. In particular, we borrow metrics from studies on network structure and intrapopulation variation to understand how an emerging infectious disease [the rabbit haemorrhagic disease (RHD)] that caused the density of the eagle's primary prey (rabbit Oryctolagus cuniculus) to dramatically drop across Europe impacted on resource use patterns of this endangered raptor. 4. Following the major RHD outbreak, substantial changes in Bonelli's Eagle's diet diversity and organisation patterns at the intrapopulation level took place. Dietary variation among breeding pairs was larger after than before the outbreak. Before RHD, there were no clusters of pairs with similar diets, but significant clustering emerged after RHD. Moreover, diets at the pair level presented a nested pattern before RHD, but not after. 5. Here, we reveal how intrapopulation patterns of resource use can quantitatively and qualitatively vary, given drastic changes in resource availability. 6. For the first time, we show that a pathogen of a prey species can indirectly impact the intrapopulation patterns of resource use of an endangered predator. [ABSTRACT FROM AUTHOR]

Aim To explore the influence of an emerging infectious disease (EID) affecting a prey species on the spatial patterns and temporal shifts in the diet of a predator over a large geographical scale. We reviewed studies on the diet of Bonelli’s eagles ( Hieraaetus fasciatus) in order to determine the repercussions of the reduction in the density of its main prey, the rabbit ( Oryctolagus cuniculus), caused by outbreaks of rabbit haemorrhagic disease (RHD) since 1988. Location Western continental Europe. Methods We compiled published and unpublished information on the diet of breeding Bonelli’s eagles from Portugal, Spain and France for a 39-year study period (1968–2006). Nonparametric tests were used in order to analyse temporal shifts in diet composition and trophic diversity ( H′) between the periods of ‘high’ (before outbreak of RHD) and ‘low’ rabbit density (after outbreak of RHD). A combination of hierarchical agglomerative clustering and non-metric multidimensional scaling (NMDS) analyses were used to test for the existence of geographical patterns in the diet of Bonelli’s eagles in each period. Results The diet of the Bonelli’s eagle consisted of rabbit (28.5%), pigeons (24.0%), partridges (15.3%), ‘other birds’ (11.6%), ‘other mammals’ (7.1%), corvids (7.0%), and herptiles (6.4%). However, RHD had large consequences for its feeding ecology: the consumption of rabbits decreased by one-third after the outbreak of RHD. Conversely, trophic diversity ( H′) increased after outbreak of RHD. At the same time, the analyses showed clear geographical patterns in the diet of the Bonelli’s eagle before, but not after, RHD outbreak. Main conclusions Geographical patterns in the diet of the Bonelli’s eagle in western Europe seem to be driven mainly by spatio-temporal variation in the abundance of rabbits and, to a lesser extent, by the local (territorial) environmental features conditioning the presence and density of alternative prey species. We show that an EID can disrupt predator–prey relationships at large spatial and temporal scales through a severe decline in the population of the main prey species. Hence we argue that strict guidelines should be drawn up to prevent human-aided dissemination of ‘pathogen pollution’, which can threaten wildlife not only at the population and species level but also at the community and ecosystem scale. [ABSTRACT FROM AUTHOR]

Predation by introduced mammals is decimating New Zealand's indigenous fauna. Understanding factors that influence this process allows resources for predator control to be applied with maximum effect. This study examines how predation of a secondary prey species (a relatively common but declining native plover, the banded dotterel Charadrius bicinctus) varied with reductions in abundance of a major prey source (rabbits), kill-trapping of predators, nest density and habitat complexity. Banded dotterels mostly nest in open braided riverbeds alongside a number of endemic threatened species. We measured the fate of 753 dotterel clutches exposed to predation by cats, ferrets and hedgehogs. We found key times and places of high predation risk. Immediately after widespread reduction in rabbit populations by rabbit haemorrhagic disease (RHD), clutch predation rates were almost as high (mean, 50%) as those recorded during past rabbit poisoning programmes (mean, 57%). Both rates were significantly higher than the mean predation rate of 22% without rabbit control, suggesting a shift in predator diet immediately after rabbit population declines. Unlike after rabbit poisoning, clutch predation rate remained high in the years after RHD. Other patterns observed included higher clutch predation rate where nest density was lower, suggesting that predation can potentially cause local extinction. Clutch predation was also higher along riverbed margins where vegetation was dense. There was equivocal evidence for an effect of predator kill-trapping on clutch predation rate. Management strategies that could potentially reduce clutch predation risks include focusing predator mitigation measures during periods of rabbit decline, maintaining them for more than one breeding season if the rabbit declines are widespread (e.g. RHD epidemics), and applying greater effort at sites with relatively low nest density and along riverbed margins where predator use is more frequent. [ABSTRACT FROM AUTHOR]

Abstract European wild rabbits originated in southwestern Europe but have been introduced into many other countries world-wide, becoming serious pests in many instances. As a consequence of rabbits being regarded so differently, applied research for their management often has opposing goals, namely their conservation or their control. Furthermore, modern gene technology has led to the concept of using genetically modified myxoma viruses for rabbit management, again with quite contrary aims in mind. In this paper we explain the possible ecological and economic consequences of using these genetically modified viruses inappropriately and we consider whether national and international regulations are sufficient to prevent improper use. If international regulations are inadequate, molecular biologists and ecologists must consider the consequences of their research and advice beyond their own country to avoid unwanted impacts. [ABSTRACT FROM AUTHOR]