Feral rabbit populations in a peri-urban area: insights about invasion dynamics and potential management strategies

AbstractWhere introduced, the European rabbit Oryctolagus cuniculus is considered among the most destructive and invasive species. To date, research focused mostly on populations of wild rabbit, whereas little is known on feral domestic rabbit populations. In this work, we reported the establishment of two self-sustaining populations of feral rabbits in Italy. Direct observations were conducted to assess rabbit range expansion and population increase over time. We also evaluated prey-predator interactions between rabbits and native red foxes Vulpes vulpes, by means of camera trapping and the analysis of fox scats. Moreover, we also assessed the social perception towards feral rabbits and the acceptability of various management options through the administration of a structured questionnaire to park visitors. Rabbit populations increased between 2018 and 2019, as well as the size of the invaded range. Rabbits are predated by foxes, but they seem to have adapted their activity rhythms to minimize the risk of predation, becoming diurnal. Park visitors loved rabbits and deemed them to be a positive presence in the park, which deserve to live there. Surgical sterilization of rabbits was the only management option which was partially supported. Feral domestic rabbits, albeit a neglected species in invasion biology, can become extremely successful invaders of urban green areas: in < 5 years, rabbits were able to colonize our study area and become a food resource for native predators and also an iconic species. These three points raise concerns about the potential impacts of invasive feral rabbits in European urban green areas and call for further research in this direction

“The Fox and the Cat”: Sometimes they do not agree

The diet of suburban foxes has been studied by analysing 200 scats collected monthly between July 2016 and July 2017, along fixed itineraries around two villages in central Italy. A significant seasonal variation in the diet was found. Fruits (berries) and coleopterans prevailed in the warm months and were replaced by feral domestic cats (mostly kittens) in the cold ones. The local overwhelming importance of the domestic cat in diet confirms the opportunistic feeding behaviour of red foxes, which may switch their diet towards easily accessible food categories, when preferred items are poorly available

Successful treatment of idiopathic knuckle pads with a combination of high-dose salicylic acid and urea topical keratolytics: A case report

Knuckle pads are benign subcutaneous and usually hyperkeratotic fibromas for which no specific treatments exist. Unspecific treatments are, most of the time, ineffective and a wait-and-see policy is often recommended to patients. However, especially in adolescents, knuckle pads are often poorly tolerated for cosmetic reasons, potentially causing embarrassment and social anxiety. Here we present the case of a young adult successfully treated with a combination of high-dose salicylic acid and urea topical keratolytics. In addition, we provide ideal diagnostic images obtained via high-resolution ultrasonography and histological features that can be used by medical practitioners to better distinguish knuckle pads from other proximal interphalangeal/metacarpophalangeal joint diseases as also from other diseases inducing swelling of periarticular soft tissues

Subspecific taxonomy of African porcupines Hystrix spp.: is there anything beyond the species level?

Taxonomy is a mistreated matter, but its role in ecology, behaviour and conservation studies is pivotal. Disentangling amongst different subspecies is challenging given the high arbitrariness level in determining thresholds of genetic and morphological distances. Splitting frenzy trends have increased the number of animal taxa and for most of them a critical redefinition is required. In this work, we reviewed knowledge and validity of subspecific taxa identified for African crested porcupines Hystrix cristata and Hystrix africaeaustralis. In the past, several subspecies were recognized for both the species, but successive works suggested H. cristata and H. africaeaustralis as monotypic species with no clear explanation. Recently, the validity of the taxon H. cristata senegalica has been claimed again. We analysed all available data and discussed all the subspecific taxa in light of both genetic and morphological data. We revalidated here the synonymy Hystrix senegalica Cuvier, 1823 = Hystrix cristata Linnaeus, 1758. Syn. rev. Two names are treated as nomina dubia: Acanthion daubentonii Cuvier, 1823 (formalization) and "Hystrix capensis Gr.". Hystrix cristata var. alba de Selys-Longchamps, 1839 has been deleted from the synonymic list ofH. cristata. Neither mitochondrial nor nuclear DNA data militate for the existence of any subspecific taxon, although further data are required for H. cristata from East Africa (e.g., Kenya and Tanzania). Similarly, morphology seems to play for a clinal variation in both species. For available data, we thus strongly recommend to keep both H. cristata and H. africaeaustralis as monotypic species

Unveiling the Genetic Diversity of Declining Population of the Harvest Mouse Micromys minutus in Italy

The Italian peninsula represented one of the main glacial refugia during climatic oscillations of the Pleistocene, currently being a biodiversity hotspot. In this work, we analysed for the first time the genetic diversity of harvest mouse populations in Italy, and we compared them with those of the rest of Eurasia. Mitochondrial cytochrome-b gene was amplified from 12 samples from throughout the Italian range. We recorded a very low genetic diversity, in line with the rest of the harvest mouse range. In the comparative phylogenetic tree, Northern Italy samples clustered together as a sister group of the rest of Europe, whereas those from Central Italy clustered with Central Europe samples. Harvest mice have recently conquered Southern Europe, i.e., possibly at the start of the Holocene. The global genetic homogeneity might be due to accidental human-mediated introductions or to the sharp decline of the habitat of the harvest mouse, which may in turn have caused severe bottlenecks in the populations of this small rodent

Profile of Small RNAs, vDNA Forms and Viral Integrations in Late Chikungunya Virus Infection of Aedes albopictus Mosquitoes

International audienceThe Asian tiger mosquito Aedes albopictus is contributing to the (re)-emergence of Chikungunya virus (CHIKV). To gain insights into the molecular underpinning of viral persistence, which renders a mosquito a life-long vector, we coupled small RNA and whole genome sequencing approaches on carcasses and ovaries of mosquitoes sampled 14 days post CHIKV infection and investigated the profile of small RNAs and the presence of vDNA fragments. Since Aedes genomes harbor nonretroviral Endogenous Viral Elements (nrEVEs) which confers tolerance to cognate viral infections in ovaries, we also tested whether nrEVEs are formed after CHIKV infection. We show that while small interfering (si)RNAs are evenly distributed along the full viral genome, PIWI-interacting (pi)RNAs mostly arise from a ~1000 bp window, from which a unique vDNA fragment is identified. CHIKV infection does not result in the formation of new nrEVEs, but piRNAs derived from existing nrEVEs correlate with differential expression of an endogenous transcript. These results demonstrate that all three RNAi pathways contribute to the homeostasis during the late stage of CHIKV infection, but in different ways, ranging from directly targeting the viral sequence to regulating the expression of mosquito transcripts and expand the role of nrEVEs beyond immunity against cognate viruses