Coming back home: recolonisation of abandoned dens by crested porcupines Hystrix cristata and European badgers Meles meles after wood-cutting and riparian vegetation mowing events

Semifossorial species excavate dens and are considered as landscape engineers, often responsible for soil oxygenation, shuffling, landslides and floods. The crested porcupine and the European badger are semifossorial mammals sharing dens in central Italy. Both species localise their setts mainly in densely vegetated areas, providing them with cover and protection from local predators and poachers. This is particularly evident for the porcupine, widely poached in central and southern Italy, whereas badgers may locally exploit burrows also in open and periurban areas. Wood-cutting and mowing of riparian vegetation surrounding den setts force both porcupines and badgers to leave their burrows. We evaluated the probability of den re-occupancy in the years following the vegetation removal, through intensive camera-trapping at 14 den setts monitored for 9 years. We performed GLMMs to test the annual probability of sett occupancy by the two species after vegetation disturbance events. The probability of re-occupying the burrow by porcupines increased with increasing time from the disturbance cessation. A similar pattern was also observed for the badger, which probability of den occupancy was also negatively correlated with the porcupine presence at the same den, confirming the aggressive behavior of this rodent. We also tested whether, since the first year after vegetation removal, the proportion of years of occupation by porcupines on the total of years has been affected by the disturbance repetition. This effect was found to be significant only for the badger. The crested porcupine, protected by international and national laws, is more sensitive than the badger, protected according to the Italian national law, to vegetation removal. A single disturbance event is sufficient to force it to abandon the den sett, followed by a slow recolonisation with growing vegetation. Conversely, the badger is sensitive to continuous vegetation removal whereas it can colonise porcupine dens abandoned after single disturbances

Alien shades of grey: New occurrences and relevant spread of Sciurus carolinensis in Italy

The eastern grey squirrel is listed among the worst invasive species throughout the world. This species of American origin is currently replacing the native Eurasian red squirrel in most of the Great Britain, as well as in parts of Ireland and Italy. It may debark trees and exert damages to woodlands and tree plantations. Therefore, its spread may be deleterious for biodiversity and environment, emphasising the need for a rapid detection in new areas of occurrence. In this work, we reported for the first time, the presence of new populations of this invasive species in Tuscany (Central Italy) and some updates and analyses regarding the status of this species in Veneto (North-Eastern Italy). Occurrences were collected through citizen-science contributory approach supported by photos, road-kills, and/or hair-tube sampling. Field investigations ad hoc were carried out in Veneto and Tuscany   to confirm the repeated reports in the surroundings of Arezzo and in the province of Siena. Although records can be possibly related to erratic or single individuals escaped from captivity, reproductive nuclei have also been detected in both regions, with the observations of juveniles and/or lactating females. The occurrence of the  species in these regions is still scarce and localised, but considering the surrounding favourable wooded habitats, a rapid removal of the animals would be required to prevent their spread

The density of badger setts in a natural river corridor (NE Italy)

The European badger Meles meles (Linnaeus, 1758) is a common semifossorial mustelid species widely distributed throughout Europe. It also shows a high degree of plasticity, adapting its spatial and temporal behaviour to live in highly disturbed environments. Badgers live in social groups occupying underground systems called setts, which could be classified as “main” (i.e., the complex systems with a great number of entrances), and as “outliers”, “annexes” and “subsidiary” (i.e., the other burrows with a low number of entrances). An extensive scientific literature occurs on the ecology and biology of this species, and some information is available also for setts density in Europe and in Italy, too. However, since badgers may inhabit a wide variety of habitats, the setts density varies significantly both locally and on a large scale. We aimed to provide setts density in a river basin in the North-East of Italy. From January to March 2022, a sett survey was conducted in the eastern plain of Friuli Venezia Giulia Region (NE Italy), along the floodplains of the lowest reaches of Isonzo/Soca river basin, from Pavia di Udine (Torre river) to the Isonzo river mouth, a natural corridor surrounded by a highly human-modified matrix. Transects to collect setts information were made in the entire area of 27.82 km2 by two or three operators. For each sett, we recorded the geo-referenced location, the type (main, subsidiary and outliers), the habitat, and the number of entrances. To estimate the density, we only considered active main setts, dividing their number by the area. A total of 22 main setts were identified within the floodplains, corresponding to a density of 0.79 setts/km2. The mean number of entrances was 13.67 (min: 5, max: 28) and they were mainly recorded in forested patches (riverine forests and transitional woodlands-shrublands). We founded other 14 subsidiaries and 13 outliers setts. The density estimated in our study area is remarkably high compared to those estimated in similar environmental conditions (e.g., Po plain area, NW Italy), but considerably lower than those reported for natural habitats (e.g., Alpine area). Even if we did not specifically analyse habitat selection of the badger for the location of setts, our results confirm the importance of the forested area and specifically riverine forests for the badgers in agricultural matrices. Furthermore, it is known that several mammals use the complex burrow system of the European badger as shelter or as a reproductive site. In a highly fragmented and disturbed area, the high density of badger setts could favour the expansion and the survival of other species, some of which are of conservation interest (e.g., European wildcat Felis silvestris and golden jackal Canis aureus) and some other invasive species (e.g., the raccoon dog Nyctereutes procyonoides)

Population counts and potential impact of two successful invaders in a town of Northern Italy: the case of ring-necked parakeet and Alexandrine parakeet in Reggio Emilia

In our paper, we reported the presence of two alien species in the city of Reggio Emilia, the ring-necked parakeet Psittacula krameri and the Alexandrine parakeet Psittacula eupatria. The ring-necked parakeet is widespread throughout Europe with many colonies known also for Italy, whereas the Alexandrine parakeet has been only recorded in the last 10-15 years and, apart from few individuals in Rome, the breeding population in Reggio Emilia is the largest one in Italy. We carried winter counts following standard methods through counts at roosts. About 78-80 ring-necked and at least 16 Alexandrine parakeets were counted, including also some hybrids between the two species, which were morphologically identified by the pale colour of the shoulders. Although no claims of crop damage are yet reported, parakeets of both species may feed on ripe and unripe persimmons in private gardens, reducing the total fruit production by up to 75-80%. Furthermore, four Savi's pipistrelle Hypsugo savii have been killed by ring-necked parakeets in early spring 2019. Therefore, the current trend of these species in the town could lead to further expansion into suburban farmland areas, increasing potential conflicts with human activities

An Unexpected Case of Heterospecific Altruistic Behaviour in a Non-Breeding Migrant Tern (Charadriformes, Sternidae)

Abstract Observations of birds feeding chicks or fledglings of a different species have already been reported in many publications. However, the benefits of the altruistic behaviour are not easy to understand, as benefits and costs of this behaviour have been poorly identified. In May 2013, in a wetland in Central Italy (Piana Fiorentina, Tuscany), some cases of interspecific feeding of an Eurasian Coot Fulica atra chick by an adult non breeding Whiskered Tern Chlidonias hybrida were witnessed. We suggest that the behaviour of the Tern was triggered by the begging of the chick or by its own hormonal status

SIGHTING OF SOUTHERN GREY SHRIKES PREYING ON RED PALM WEEVILIN TWO COUNTRIES

Rhynchophorus ferrugineus, commonly known as Red Palm Weevil, is one of the most destructive and invasivepalm pests’ species in the world. The most important host species are coconut palms, oil palms, Canary Island palms and itis considered as a key pest in date palms crops. As the existing chemical – based treatments are not efficient, the eco-friendly biological control methods have now attracted high interest. In this note, we report for the first time the predationof the Red Palm Weevil by two subspecies of Southern Grey Shrike Lanius meridionalis, once in Spain and once in SaudiArabia

Alien parakeets as a potential threat to the common noctule Nyctalus noctula

The ring-necked parakeet Psittacula krameri (Aves: Psittaciformes) is a widely distributed species of Asian and African origin, which occurs with over 40 alien populations in the rest of the world. Most established populations of this species are showing a clear trend of territorial expansion and numerical growth. Recent reviews highlighted that one of the main impacts by alien ring-necked parakeets is the competition with threatened bat spe cies using trunk cavities as roosts. In Italy, the only known reproductive population of Nyctalus bats (Mammalia: Chiroptera) occurs in an urban area in the central part of the country, surrounded by increasing and expanding populations of ring-necked parakeets. In this work, we updated the population status of both ring-necked and Alexandrine parakeets and breeding noctule bats in the region. Then, we ran a species distribution model using Maxent software to analyze the environmental suitability of the region for the ring-necked parakeet and a connectivity model using Circuitscape software to predict the possibility of its expansion in the area occupied by breeding noctule bats. We recorded a high number of individual parakeets and breeding colonies, together with a remarkable noctule popula tion decline, from about 400 to about 120 individuals, in the last 20 years, possibly due to urban green management practices. Although some ring-necked parakeets have already been observed in the study area, there is no evidence of reproduction in the surroundings of the noctule colony. However, our model showed a high environmental suitability for the ring-necked parakeet in the area occupied by breeding noctules. As well, the connectivity model showed the potential for a direct fow of individuals from the main urban centers to the area used by noctule bats. The arrival of alien parakeets to the area occupied by the bat breeding colony should be tightly monitored by surveying the suitable areas for this bird, as well as the identifed ecological corridors. Early detection of new invasions, together with a sustainable urban green management practice, may prevent the extinction of the southernmost breeding colony of the common noctule

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