European Rabbit Oryctolagus Cuniculus Research Articles

Сучасна теріофауна лівобережжя Каньйонового Придністер’я

The article analyses the current state of the mammal fauna of part of Podolian Transnistria, which lies between the rivers Zbruch and Zolota Lypa (southern Ternopil Oblast, Ukraine). To designate the region, the publication uses a term from old Polish sources—Canyon Transnistria—which reflects the prevailing landform. The area of research in old faunal summaries is mentioned only as part of wider regions, such as Galicia, western Ukraine, or Ternopil Oblast. Over the past decades, the number of publications on the mammal fauna of this particular region has increased substantially, which makes it possible to make a summary overview. The modern mammal fauna of the region comprises 60 species belonging to 7 orders, 20 families, and 41 genera. Over the past 70 years, the mammal fauna of the studied region has undergone significant changes. Its dynamic component is almost 27%. It includes species of recent immigrants (Blyth’s pipistrelle Pipistrellus lepidus, mound-building mouse Mus spicilegus, muskrat Ondatra zibethicus), as well as two species that recovered their range (Eurasian beaver Castor fiber, wildcat Felis silvestris); the dynamic component also includes three extinct or probably extinct species—Geoffroy’s bat (Myotis emarginatus), Podolian ground squirrel (Spermophilus odessanus), and European rabbit (Oryctolagus cuniculus). A group of phantom species has been singled out, which are known only from single old finds, and modern studies of these species are far from sufficient to understand their status. It includes the lesser mouse-eared bat (Myotis oxygnathus), Nathusius’s pipistrelle (Pipistrellus nathusii), southern birch mouse (Sicista loriger), and Podolian mole rat (Spalax zemni). Such species as the long-eared bat (Plecotus austriacus) and the pygmy field mouse (Sylvaemus uralensis) appeared in the lists of the mammal fauna of the region due to changes in taxonomy. The rare component of the mammal fauna comprises 18 species (30%). The article provides a brief description of the current state of mammal populations in the region. Conservation recommendations are given for rare species.

High‐resolution mapping of rabbit (Oryctolagus cuniculus) densities for targeted conservation management

Abstract Despite the staggering economic and ecological impacts of invasive animals, maps of their distribution are often only broad generalisations. Detailed knowledge about the spatial distribution of pest animals is crucial to efficiently reduce their numbers in open landscapes where no conservation fencing, or natural boundaries exist. Our case study tests a random but spatially balanced transect design to collect data on the distribution of the European rabbit (Oryctolagus cuniculus), a major destructive pest species in Australian ecosystems, and create distribution maps in relation to abiotic and biotic features. We surveyed an area of 650 km2 in the semi‐arid Flinders Ranges of South Australia using 95 transects (1.4 km length by 50 m width), that were placed with a method originally developed for surveying the ocean‐floor and applied for the first time in terrestrial ecosystems. According to a hurdle model fitted to our data set, the presence of rabbit warrens is influenced by geology, vegetation cover and the topographic wetness index, whereas the number of holes per warren depends on the ruggedness of the terrain, the vegetation cover and whether it has previously been destroyed. The model predicted the numbers of rabbit holes with up to 96.4% accuracy and at a previously unavailable resolution, providing a significant improvement in detail of the distribution of this feral animal. Synthesis and applications: A reliable, high‐resolution map of the distribution of rabbit densities was generated with surveying of less than 1% of the study area, information that can now be used to direct targeted conservation management efforts. This method is highly accurate and can still be improved in future studies.

Mucoid enteropathy/epizootic rabbit enteropathy in two species of cottontail rabbits: four recent cases

Mucoid enteropathy/epizootic rabbit enteropathy is a disease of domestic European rabbits (Oryctolagus cuniculus) that has been recognized for nearly 50 years but is still not well understood. Morbidity and mortality are high and can lead to large losses in domestic rabbit production facilities. Recently, the Colorado Wild Rabbit Foundation identified four cases with similar presentations in two species of cottontail rabbits (Sylvilagus spp.) undergoing rehabilitation (2020–2022). Clinical signs, gross pathology, and histopathology findings were consistent with what has been described in domestic rabbits.

European rabbit (Oryctolagus cuniculus) as seed disperser in arid ecotones of Argentina: non-native herbivore facilitation of native and non-native plants

European rabbit (Oryctolagus cuniculus) as seed disperser in arid ecotones of Argentina: non-native herbivore facilitation of native and non-native plants

Hepatobiliary organoids derived from leporids support the replication of hepatotropic lagoviruses.

The genus Lagovirus of the family Caliciviridae contains some of the most virulent vertebrate viruses known. Lagoviruses infect leporids, such as rabbits, hares and cottontails. Highly pathogenic viruses such as Rabbit haemorrhagic disease virus 1 (RHDV1) cause a fulminant hepatitis that typically leads to disseminated intravascular coagulation within 24-72 h of infection, killing over 95 % of susceptible animals. Research into the pathophysiological mechanisms that are responsible for this extreme phenotype has been hampered by the lack of a reliable culture system. Here, we report on a new ex vivo model for the cultivation of lagoviruses in cells derived from the European rabbit (Oryctolagus cuniculus) and European brown hare (Lepus europaeus). We show that three different lagoviruses, RHDV1, RHDV2 and RHDVa-K5, replicate in monolayer cultures derived from rabbit hepatobiliary organoids, but not in monolayer cultures derived from cat (Felis catus) or mouse (Mus musculus) organoids. Virus multiplication was demonstrated by (i) an increase in viral RNA levels, (ii) the accumulation of dsRNA viral replication intermediates and (iii) the expression of viral structural and non-structural proteins. The establishment of an organoid culture system for lagoviruses will facilitate studies with considerable implications for the conservation of endangered leporid species in Europe and North America, and the biocontrol of overabundant rabbit populations in Australia and New Zealand.

Habitat and food preferences of European rabbits in core and edge populations along the invasion front Patagonia-Monte, Argentina.

The European rabbit Oryctolagus cuniculus is an exotic herbivorous mammal undergoing an active phase of geographical expansion in the arid ecosystems of Argentina. The Adaptive Flexibility Hypothesis states that populations at the range edge (new populations) will exhibit greater flexibility in the use of resources compared with populations located in the range core (older populations). The objective of this work was to compare the rabbit's use of spatial and trophic resources in relation to the establishment time of their populations. The sampling was carried out for 2 years (2017 and 2018) in sites with different establishment times for rabbit populations. Random sampling stratified by type of habitat was applied using 115 fixed strip transects of 1,000 m2 laid out across the study areas. Fresh rabbit signs were recorded in each transect, and environmental and anthropic variables were measured. Our results show that the individuals from the range edge are more selective in the use of habitat than those from the range core. At the microhabitat level, we observed a pattern in the particular components of habitat use by rabbits mainly linked to food availability and proximity to water. From a trophic perspective, rabbits could show flexible adjustment to novel conditions and environments in the range edge. The variability in resource use by the European rabbit confirms its ecological flexibility, pivotal for their advance toward new environments in Argentina.

Population genomic structures and signatures of selection define the genetic uniqueness of several fancy and meat rabbit breeds.

Following the recent domestication process of the European rabbit (Oryctolagus cuniculus), many different breeds and lines, distinguished primarily by exterior traits such as coat colour, fur structure and body size and shape, have been constituted. In this study, we genotyped, with a high-density single-nucleotide polymorphism panel, a total of 645 rabbits from 10 fancy breeds (Belgian Hare, Champagne d'Argent, Checkered Giant, Coloured Dwarf, Dwarf Lop, Ermine, Giant Grey, Giant White, Rex and Rhinelander) and three meat breeds (Italian White, Italian Spotted and Italian Silver). ADMIXTURE analysis indicated that breeds with similar phenotypic traits (e.g. coat colour and body size) shared common ancestries. Signatures of selection using two haplotype-based approaches (iHS and XP-EHH), combined with the results obtained with other methods previously reported that we applied to the same breeds, we identified a total of 5079 independent genomic regions with some signatures of selection, covering about 1777 Mb of the rabbit genome. These regions consistently encompassed many genes involved in pigmentation processes (ASIP, EDNRA, EDNRB, KIT, KITLG, MITF, OCA2, TYR and TYRP1), coat structure (LIPH) and body size, including two major genes (LCORL and HMGA2) among many others. This study revealed novel genomic regions under signatures of selection and further demonstrated that population structures and signatures of selection, left into the genome of these rabbit breeds, may contribute to understanding the genetic events that led to their constitution and the complex genetic mechanisms determining the broad phenotypic variability present in these untapped rabbit genetic resources.

High Mortality of Wild European Rabbits during a Natural Outbreak of Rabbit Haemorrhagic Disease GI.2 Revealed by a Capture-Mark-Recapture Study

Rabbit haemorrhagic disease virus (RHDV) GI.2 has caused significant declines in the abundance of wild European rabbits (Oryctolagus cuniculus), contributing to the species being recently classified as “endangered” in its native range. The epidemiology of this virus is still poorly understood despite its relevance for domestic and wild rabbits. During a longitudinal capture-mark-recapture (CMR) study of wild Iberian rabbits, O. c. algirus, in a semiextensive breeding enclosure, an outbreak of RHDV GI.2 took place in January-February 2022, allowing us to estimate key epidemiological parameters of a natural outbreak. From April 2021 to July 2022, 340 rabbits were captured 466 times and individually identified, and some were vaccinated against myxoma virus (MYXV) and/or RHDV GI.2. Sera were collected and tested for IgG specific for MYXV and RHDV GI.2, and data were analyzed using multievent CMR models. During six weeks in January-February 2022, an estimated 81.0% (CI95 77.1–84.3%) of the population died. Intensive aboveground searches could recover 189 carcasses (50.5% of the estimated mortality, CI95 41.8–63.4%), with RHDV GI.2 detected in 6/7 tested. Apparent RHDV GI.2 seroprevalence rose from 15.4% (CI95 8.0–27.5%) in January 2022 to 87.9% (CI95 72.7–95.2%) in February 2022. The apparent mortality of RHDV GI.2-seropositive rabbits during the outbreak was estimated as null, while for seronegative rabbits, it was 76.0% (CI95 53.8–90.3%). Among the seronegative rabbits, mortality was higher in unvaccinated (100%) than in recently vaccinated (60.0 ± 16.6%) and in females (100%) than in males (52.0 ± 17.1%). Infected carcasses in the burrows might explain the medium-term disease persistence in the population following the outbreak. Rabbits with antibodies at the cutoff for seropositivity were fully protected from fatal infection. Females had a higher fatality rate than males, underscoring the impact of RHDV GI.2 on the population dynamics of this endangered species.

Nutritional ecology of European rabbit (Oryctolagus cuniculus): Factors affecting chemical composition of gastric content.

Nutritional ecology seeks to unravel the extensive web of nutritional links that directs animals in their interactions with their ecological and social environments. European rabbit (Oryctolagus cuniculus) populations its endemic locations are declining and it is considered a keystone species of the Mediterranean ecosystem prompteing the interest in its conservation. The main aim of this study was to determine the nutritional composition of the diet of European rabbits through the relative and absolute chemical composition of the gastric content. To address this objective, gastric content was collected from 80 European rabbits in a Mediterranean area for the analysis of its chemical composition. To this end, gastric content was analyzed for dry matter (DM), organic matter (OM), ash, crude protein (CP), highly digestible nonnitrogenous nutrients (HDNN), neutral detergent fibre (NDF), acid detergent fibre (ADF) and lignin. The rabbits were divided into two groups: EMPTY and FULL, depending on the level of stomach filling, directly related to food intake. Our results revealed a positive correlation between the rabbits weight with DM in the gastric content, total gastric content with DM in the gastric content, and DM in gastric content with all chemical parameters analysed. The mean relative values obtained were 8.8%, 25.5%, 40.4% and 25.4%, for ash, CP, NDF and HDNN, respectively. Moreover, EMPTY rabbits had both a proportional (+19%, p = 0.002 and -40%; p = 0.004, on NDF and HDNN, respectively) and absolute (-38%, p = 0.014, -52%; p = 0.012, -52%; p = 0.011 and +83%; p = 0.008 for OM, ash, HDNN, and lignin, respectively) different proportion of nutrients in gastric contents than FULL animals. Since there is a connection between this availability and the fitness of this species, understanding the chemical composition of the rabbit's diet can be utilised to delve into its biology. Our study provides information that will help elucidate the factors affecting the chemical composition of the gastric content of European rabbits to assist land use planners and conservationists in identifying sites for conservation in Mediterranean ecosystems.

The potential role of scavenging flies as mechanical vectors of Lagovirus europaeus/GI.2

The European rabbit (Oryctolagus cuniculus) populations of the Iberian Peninsula have been severely affected by the emergence of the rabbit haemorrhagic disease virus (RHDV) Lagovirus europaeus/GI.2 (RHDV2/b). Bushflies and blowflies (Muscidae and Calliphoridae families, respectively) are important RHDV vectors in Oceania, but their epidemiological role is unknown in the native range of the European rabbit. In this study, scavenging flies were collected between June 2018 and February 2019 in baited traps at one site in southern Portugal, alongside a longitudinal capture-mark-recapture study of a wild European rabbit population, aiming to provide evidence of mechanical transmission of GI.2 by flies. Fly abundance, particularly from Calliphoridae and Muscidae families, peaked in October 2018 and in February 2019. By employing molecular tools, we were able to detect the presence of GI.2 in flies belonging to the families Calliphoridae, Muscidae, Fanniidae and Drosophilidae. The positive samples were detected during an RHD outbreak and absent in samples collected when no evidence of viral circulation in the local rabbit population was found. We were able to sequence a short viral genomic fragment, confirming its identity as RHDV GI.2. The results suggest that scavenging flies may act as mechanical vectors of GI.2 in the native range of the southwestern Iberian subspecies O. cuniculus algirus. Future studies should better assess their potential in the epidemiology of RHD and as a tool for monitoring viral circulation in the field.

The nutritional strategy of European rabbits is affected by age and sex: Females eat more and have better nutrient optimisation.

The ecological interest in the European rabbit (Oryctolagus cuniculus) has grown since it was declared an endangered species. Nutrition is fundamental in its dispersion and the key to its success. This is the main reason why knowledge of their nutritional preferences/requirements could play a fundamental role in rabbit biology and, therefore, in their conservation. The objectives of the work will be to elucidate how age and sex affect both nutritional preferences/requirements, and the nutrient optimisation of European rabbits. To address this gap, 70 wild European rabbits were studied. The rabbits were divided according to their age: adult (n = 43) and young (n = 27). Two groups were differentiated according to the adult rabbits' sex: females (n = 28) and males (n = 15). We analysed the relative (%) and absolute (g) chemical composition of the rabbits' gastric contents: dry matter (DM), ashes (ASH), crude protein (CP), ether extract (EE), neutral detergent fibre (NDF), acid detergent fibre (ADF), and lignin, hemicelluloses and celluloses, highly digestible nonnitrogenous nutrients (HDNN: fat, starch, and soluble fibre), well from the blood was analysed with plasmatic urea nitrogen (PUN), nonesterified fatty acid (NEFA) and glucose (GLU). As a nutrient optimisation measure, the following indices between blood metabolites and stomach content were calculated: PUN/CP total content, NEFA/DM total content and GLU/DM total content ratios. Our works showed that age and sex affected the nutritional strategy of rabbits. Regarding age: adults showed lower CP (-14%; p = 0.0217) and higher HDNN (+21%; p = 0.0399) relative content than young rabbits, and absolute amount of most nutrients: DM (+59%; p = 0.001), OM (+43%; p = 0.0049), ASH (+54%; p = 0.0085), Hemicelluloses (+73%; p = 0.0084), Cellulose (+27%; p = 0.0452), and HDNN (+63%; p = 0.0012). In addition, adults showed better nutrient optimisation. Sex did not affect the relative chemical composition of the gastric content, but it showed a clear higher gastric content by females (+85%; p < 0.0001) and higher intake of most of the absolute chemical components: DM (+64%; p < 0.001), CP (+56%; p = 0.0005), OM (+58%; p = 0.0001), ASH (+44%; p = 0.0123), HDNN (+39%; p = 0.001), NDF (+59%; p = 0.001), ADF (+64%; p = 0.0003), lignin (+82%; p = 0.0036) and cellulose (+58%; p = 0.0002). Finally, we observed that females had better nutrient optimisation than males. This works supports the idea that feeding ecology and nutrition are particularly relevant to reproductive success and fitness in wild animals.

Modeling the contribution of antibody attack rates to single and dual helminth infections in a natural system

Within-host models of infection can provide important insights into the processes that affect parasite spread and persistence in host populations. However, modeling can be limited by the availability of empirical data, a problem commonly encountered in natural systems. Here, we used six years of immune-infection observations of two gastrointestinal helminths (Trichostrongylus retortaeformis and Graphidium strigosum) from a population of European rabbits (Oryctolagus cuniculus) to develop an age-dependent, mathematical model that explicitly included species-specific and cross-reacting antibody (IgA and IgG) responses to each helminth in hosts with single or dual infections. Different models of single infection were formally compared to test alternative mechanisms of parasite regulation. The two models that best described single infections of each helminth species were then coupled through antibody cross-immunity to examine how the presence of one species could alter the host immune response to, and the within-host dynamics of, the other species. For both single infections, model selection suggested that either IgA or IgG responses could equally explain the observed parasite intensities by host age. However, the antibody attack rate and affinity level changed between the two helminths, it was stronger against T. retortaeformis than against G. strigosum and caused contrasting age-intensity profiles. When the two helminths coinfect the same host, we found variation of the species-specific antibody response to both species together with an asymmetric cross-immune response driven by IgG. Lower attack rate and affinity of antibodies in dual than single infections contributed to the significant increase of both helminth intensities. By combining mathematical modeling with immuno-infection data, our work provides a tractable model framework for disentangling some of the complexities generated by host-parasite and parasite–parasite interactions in natural systems.

Cooke’s index: A simple, cost-effective method for multiple practitioners to estimate European rabbit abundance

The development of evidence-based tools that help to monitor wildlife populations is essential to assess the success of management interventions. Here, we evaluated the reliability of a simple method to estimate the abundance of the European rabbit (Oryctolagus cuniculus), which is likely one of the most managed vertebrate species worldwide. Cooke’s method involves noting the distribution and frequency of sightings of rabbit fecal pellets and accordingly scoring the abundance of rabbits on a scale 0–5. To assess its reliability, we used information collected during 101 rabbit surveys conducted across mainland Spain during the summer of 2022. In each 4-km walked transect, we estimated rabbit abundance using Cooke’s method every 400 m (i.e., 10 indexes), and pellet counts (2 plots per 100 m walked, i.e., 80 counts), which were used as a reference index. Our results revealed a strong correlation between the estimates of rabbit abundance obtained using Cooke’s method and the number of pellets counted per m2 regardless of the statistical approach used. This suggests that Cooke’s method provides a simple and inexpensive way of estimating the abundance of European rabbits, which we believe that can be very useful for non-expert land managers after a very short training period. Importantly, our findings demonstrate that it is reliable to estimate rabbit abundance in different land uses. In addition, Cooke’s method can be used in different seasons, is not affected by circadian activity of rabbits, seems to work well across the whole range of rabbit abundance, and may be useful for estimating rabbit abundance at different spatial scales. As everyday people rather than scientists are generally involved in managing European rabbits, we strongly recommend this simple method that allows rabbit abundance to be quickly estimated so that management decisions can be made. More broadly, we encourage researchers to investigate the usefulness of similar monitoring tools for other mammal species that are often surveyed through counting their pellets.

European Rabbit Invasion in a Semi-Arid Ecosystem of Chile: How Relevant Is Its Role in Food Webs?

The European rabbit (Oryctolagus cuniculus) is one of the main invasive species in Chile, where it became naturalized ca. 150 years ago. Their high reproductive capacity, lack of specialist predators, and great adaptability favored the settlement of rabbits in diverse mainland and island ecosystems of the country. Recently, rabbits have become central players in semi-arid ecosystems, such as those represented in Las Chinchillas National Reserve in north-central Chile. We undertook to analyze the place and role of rabbits in the food web of that Reserve, based on a bibliographic review and long-term annual data gathered from 1987 until 2022 (36 years). Results showed that the network comprised 77 species, where 69% were primary producers (plants), 18% were mid-level consumers (herbivores), and 13% were top-level consumers (predators). The most connected species in the food web was the rabbit, which positively or negatively affected the species interacting with it. Predators such as Galictis cuja, Geranoaetus polyosoma, Leopardus colocolo, and Puma concolor, and the scavenger Vultur gryphus, could be negatively affected by an eventual decrease (natural or human-caused) in the rabbit population of the Reserve. To the contrary, primary producers such as Oxalis perdicaria, Plantago hispidula, Schizanthus parvulus, Senna cumminggi, and Tropaeolum azureum could be positively affected by an increase in their biomass in response to a decrease in rabbits, favoring native rodents. We consider that analyzing the rabbit-centered food web and its impacts on native interacting species allows a better understanding of the relevance of invasive species in the local community, providing conceptual tools for rabbit management.

The Role of PRLR Gene Polymorphisms in Milk Production in European Wild Rabbit (Oryctolagus cuniculus).

One of the problematic points of rabbit breeding is that the nutritional requirements of the kits are not fully satisfied by the does' milk production from the third week of lactation onwards. The prolactin receptor gene has a significant effect on reproductive processes, and its polymorphisms have been associated with milk production in several species (cattle, goats, sheep, and buffalo). The European wild rabbit (Oryctolagus cuniculus), has a more diverse genetic background compared to domesticated lines. In the course of our study, sequencing of the 1210 bp long segment of the PRLR gene promoter region was accomplished. We detected four point mutations (SNP1-407G > A, SNP2-496G > C, SNP3-926T> and SNP4-973A > C) and one microsatellite at position 574. In our population, the four SNPs were segregated into four genotypes: AACCCCCC, GGGGTTAA, AAGGTTAC, and GGGGTCAC. Our results show that the genotype in the homozygous form is associated with higher milk production (1564.7 ± 444.7 g) compared to the other three genotypes (AACCCCCC 1399.1 ± 326.8 g; GTGACCTT 1403.8 ± 517.1 g; GGGGTCAC 1220.0 ± 666.2 g), and the short microsatellite repeat (167 bp) also coincides with significantly higher milk production (1623.8 ± 525.1 g). These results make the marker-assisted selection possible also for domesticated lines.

Historical ecology and current abundance of the translocated Chilla or Grey fox Lycalopex griseus on the large Tierra del Fuego Island shared by Argentina and Chile

AbstractIn 1951, a batch of 24 young animals of both sexes of Chilla or Grey fox Lycalopex griseus from continental Magallanes region, Chile – and perhaps also from adjacent continental Argentina – were released at Onaisin (65 km ESE Porvenir town, 53°18′S) on Tierra del Fuego Island in southernmost South America, to control a European rabbit (Oryctolagus cuniculus) irruption that was considered detrimental to sheep (Ovis aries) ranching. Up to now, no attention has been paid to the temporal course of that introduction. Here we provide a historical account of the presence of foxes on the Tierra del Fuego Archipelago, starting with Charles Darwin account of 1839 until present. We also review the regulatory framework concerning hunting of those foxes and tally their culling for export of pelts. Finally, we provide estimates of the abundance of Chilla foxes on Tierra del Fuego Island for the period 1999–2007 and for 2021, and highlight their current spread. These translocated foxes have become an abundant and functional part of both steppe and forest ecosystems on the Fuegian archipelago, even though they are killed by hunters, without spatial, temporal, or numerical limits. We conclude that interesting scientific opportunities are being missed regarding the population genetics of a species that may have left founding effects and genetic bottlenecks in Tierra del Fuego, and perhaps some peculiar continental markers among the island population. We also raise the question whether this introduced native species may be deemed invasive, calling for research to determine its impact in its new environment.

Understanding the impact of wild boar on the European wild rabbit and red-legged partridge populations using a diet metabarcoding approach

European wild rabbit (Oryctolagus cuniculus) and red-legged partridge (Alectoris rufa) are main small game species of conservation concern in Mediterranean ecosystems. To date, their presence in wild boar’s (Sus scrofa) diet and factors driving their consumption have been little investigated. A genetic metabarcoding approach was used on 80 wild boar faeces collected from four hunting estates devoted to small game hunting during two different seasons. Abundances of wild boar, rabbits and partridges were first estimated. Results showed DNA of seventeen chordate species. The highest frequency of occurrence (FO) corresponded to mammals and birds, with 77.6 and 22.3%, respectively. DNA of game species was detected in 39/71 (FO = 55.0%) samples, highlighting the presence of European wild rabbit in 27 (FO = 38.0%) and red-legged partridge in eight (FO = 11.3%). Dietary composition varied between seasons and estates, being rabbit the main responsible (explaining 35.26% and 39.45% of differences, respectively). Rabbit FO in the diet was positively related to the abundance of wild boar and rabbit density on the estate. It was greater in autumn and in estates where rabbits were hunted. Regarding red-legged partridge, a significant and positive relationship between its population density and its diet FO was observed, without significant differences between seasons or estates. Overall, our results suggest wild boar as an opportunistic species whose diet is largely determined by the relative availability of different food resources. Its ecological role concerning small game species in Mediterranean agroecosystems seems to be more related to consumption of carrion during the hunting season than to direct predation.

Co-occurrence patterns and habitat selection of the mountain hare, European hare, and European rabbit in urban areas of Sweden

Assessing the underlying mechanisms of species co-occurrence patterns can be challenging as biotic and abiotic factors are hard to disentangle. To date, few studies have investigated co-occurrence patterns of mammals within urban areas. As urban areas are increasingly used as habitat by wildlife, there is a need for a better understanding of urban ecology to facilitate human-wildlife co-existence. Here, we investigated co-occurrence patterns and habitat selection of the European hare (Lepus europaeus), mountain hare (L. timidus), and European rabbit (Oryctolagus cuniculus) inside urban areas of Sweden, using joint species distribution models and generalized linear mixed models based on citizen science observations. All three species were observed within urban areas, but European hares and rabbits appear to be more successful urban colonizers compared to mountain hares. Overall, our findings suggested that urban occurrence by all three lagomorphs was related to suitable conditions within the distribution of each species (e.g., climate and elevation), rather than by the presence of other lagomorph species or specific land cover types within urban areas. On a finer spatial scale, European hares and rabbits generally selected for green urban areas and mountain hares for residential gardens, which likely constitute suitable foraging sites. Moreover, overlap in activity times between European hares and rabbits was mediated by land cover type and sympatry. Our findings contribute to the understanding of urban ecology and provide insights for management measures of the three lagomorphs in urban areas of Sweden.

A new longevity record for a wild European rabbit (Oryctolagus cuniculus) from South Australia

A population of wild European rabbits (Oryctolagus cuniculus) was regularly monitored from November 1996 to April 2022, using mark–recapture as part of a longitudinal epidemiological study into two Australian rabbit biocontrol agents, rabbit haemorrhagic disease (RHD) and myxomatosis. A female rabbit, first captured as a subadult on 26 October 2009, was recaptured 16 times before its final capture on 19 February 2019. The longevity of this rabbit, from its calculated birth date to the date of its last capture, was 9.5 years. This is a record lifespan for a wild European rabbit – acknowledging that such longevity might be specific to our site in temperate South Australia. It exceeds our previous reported record from the same site by 2 years.

Rabbit warrens: an important resource for invasive alien species in semi-arid Australia

Context The decline and extinction of native burrowing mammals across much of Australia has resulted in a loss of underground refugia constructed by native fauna in the environment. The introduced European rabbit (Oryctolagus cuniculus) is now the most widespread mammalian burrower across Australia. Rabbits are an invasive species in Australia, and the destruction of rabbit warrens for pest management is common practice. This destruction of warrens removes a potential refuge for both rabbits and other species in the environment. In landscapes where critical weight range burrowing mammals have declined, the widespread destruction of rabbit warrens removes many underground refuges for several commensal animal species. Aims To identify the use of rabbit warrens by fauna in the seasonally hot, semi-arid Ikara-Flinders Ranges National Park (IFRNP) in South Australia. Methods We used camera traps placed at burrow entrances of warrens and nearby structure to identify the vertebrate species that interact with rabbit warrens in the IFRNP. Key results We recorded 11 bird, nine mammal and eight reptile species present at the entrances of rabbit warrens. Only four of the taxa recorded on cameras in our study showed a preference for warrens over adjacent above-ground structure, three of them introduced species. The alien commensal species recorded using the burrows were rabbits, house mice (Mus musculus) and feral cats (Felis catus). Conclusions Rabbit warrens in the IFRNP are an important resource for a range of native and alien commensal species. In our study, they seem to be of special importance for introduced species. Implications Warren removal in the IFRNP may negatively impact native commensal species in treated areas but is likely to be of long-term net benefit for a wider range of native animals.