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The spreading of invasive species in new continents can vary from slow and limited diffusion to fast colonisations over vast new areas. We studied the sacred ibis Threskiornis aethiopicus along a 31-year period, from 1989 to 2019, with particular attention to the first area of release in NW Italy. We collected data on species distribution through observations by citizen science projects, population density by transects with distance method, breeding censuses at colonies, and post breeding censuses at roosts. The birds counted at winter roosts in NW Italy increased from a few tens up to 10,880 individuals in 2019. Sacred ibises started breeding in 1989, with a single nest in north-western Italy. The number of breeders remained very low until 2006, when both overwintering and breeding sacred ibises started to increase exponentially and expand their range throughout northern Italy with isolated breeding cases in central Italy. In 2019, the number of nests had increased to 1249 nests in 31 colonies. In NW Italy, the density of foraging birds averaged 3.9 ind./km2 in winter and 1.5 ind./km2 in the breeding period, with a mean size of the foraging groups of 8.9 and 2.1 birds respectively. Direct field observations and species distribution models (SDM) showed that foraging habitats were mainly rice fields and wetlands. A SDM applied to the whole Italian peninsula plus Sardinia and Sicily showed that the variables best related to the SDM were land class (rice fields and wetlands), altitude, and the temperature seasonality. The areas favourable for species expansion encompass all the plains of Northern Italy, and several areas of Tuscany, Latium, Sardinia, and Apulia. [ABSTRACT FROM AUTHOR]

The article presents a study on habitat selection and population density of Sylvilagus floridanus or eastern cottontail in Italy compared to Lepus europaeus or native European hare. The study surveyed cottontails and hares in 13 areas, and night count was used to analyze habitat use and population densities during feeding. The study showed that both species used natural herbaceous vegetation as resting areas, but during feeding, cottontails are found in meadows while hares are in open fields.

The article discusses a study which surveyed a heronry for 16 years to study nest site selection in relation to bird species presence and vegetation structure in Italy. It has been observed that the black-crowned night heron was the most abundant species, while little egret and grey heron increased only in the last years. The researchers suggested that black locusts became taller and were less suitable for night herons as developing shrubs provided alternative nest sites at more protected lower elevations.

Introduced coypu (Myocastor coypus) damage crops and natural vegetation and undermine riverbanks. We controlled coypu with cage traps to protect vegetation in 3 wetlands in the Park of the Rivers Po and Orba (northwestern Italy). During a 3-year trial, coypu were controlled in the Natural Reserve of Valenza (NRV), an area with a low degree of colonization, but not in one with a high immigration rate. In NRV park wardens were involved for 18 man-days of work annually, and the cost was 1,518 Euros (1,867 U.S. dollars) per year. From 2001 a control program was carried on in the 3 areas. Removal densities (0.06-1 .3 animal/ha) suggested that 2 trapping periods annually were adequate to slow down coypu population increase. The recovery of yellow waterlily (Nuphar lutea) in 3 plots and colonization of new ponds by vegetation indicated that coypu were maintained at a level sustainable for vegetation development. [ABSTRACT FROM AUTHOR]

Colonial waterbirds, a major biodiversity element occurring in the core of ultra-anthropized Europe, are ideal indicators of the wellness of inland wetlands. Nonetheless, there is a critical knowledge gap in their trend and population status. We present an uninterrupted 47 years-long dataset of the breeding populations of 12 species of colonial waterbirds (Ardeidae, Phalacrocoracidae, Plataleidae, Threskiornitidae) throughout a 58,000 km 2 agricultural region in the higher Po basin (NW Italy). A trained team of collaborators censused with standardized field techniques the number of nests of each species at 419 colonies in the 1972-2018 period, summing up a total of 236,316 records. Data cleaning and standardization were performed for each census year, ensuring robust and consistent data. This dataset is among the largest ever collected for a guild of European vertebrates. It has already been used to describe the factors influencing population trends, and still offers opportunities to explore a wide range of key ecological processes such as biological invasions, global change consequences and biodiversity impact of agricultural practices., (© 2023. The Author(s).)