Matteo De Luca’s research while affiliated with University of Trieste and other places

Coralligenous bioconstructions are priority habitats crucial for the protection of Mediterranean marine biodiversity. Among these bioconstructions, the mesophotic biogenic reefs of the northern Adriatic are of particular concern due to their ecological relevance and the high levels of human pressure in the region. Thus, effective monitoring strategies are vital for the conservation and management of these fragile environments. In this study, we investigated the multivariate spatial and temporal patterns of sessile macrobenthos on biogenic reefs within two areas of a Natura 2000 site in the northern Adriatic over a four-year period. We also classified the ecological status of reefs based on the NAMBER index, specifically tailored for these peculiar bioconstructions. Our findings revealed that temporal trajectories of assemblages significantly differed between the two investigated areas, mostly due to larger fluctuations in algal turf abundance in the area closest to the coast, which is putatively more exposed to human impacts. In this area, the index identified a “Moderate” status during the period of peaking turf abundance, while the reef status consistently remained “Good” in other periods and in the area located further from the coast. This highlights the index sensitivity in reflecting actual changes in assemblages potentially associated with reef degradation.

The Mediterranean Shag Gulosus aristotelis desmarestii is a conservation priority seabird endemic to the Mediterranean and Black Seas that is considered a valuable sentinel of marine ecosystem health. however, knowledge of its population size and dynamics in the Adriatic Sea is limited. here, the majority of the population breeds in Croatia, with a high proportion of birds migrating northwards to the Gulf of Trieste and Venice Lagoon during the non-breeding period. To bridge this knowledge gap, a first coordinated census was undertaken in 2020 and 2021 in the Adriatic region (Italy, Slovenia and Croatia), which supports 20-33% of the total non-breeding Mediterranean subspecies population. In 2020 a total of 4,993 birds were counted while in 2021 the count was 4,871. Italy hosted the largest number of birds (x = 3,040), followed by Croatia (x = 951) and Slovenia (x = 941), with most of the birds (c. 69%) roosting on mussel farms. To fully comprehend the non-breeding population dynamics, we conducted an estimation of the 13-year (2010-2022) population trend in the Gulf of Trieste. During this period, the population strongly declined (–44.7%) for reasons yet to be identified. In 2012-2014, a population fluctuation coincided with an exceptionally wet winter and spring at the Croatian breeding colonies. It is possible that changes in migration strategy, such as new migratory routes, by this partial migrant may have partially offset the decline of birds in the Gulf of Trieste, as the Venice Lagoon population increased during the same period. Overall, the Adriatic population appears to be declining and yet subject to dynamic changes in its non-breeding distribution. To fully comprehend the reasons behind this trend, further research of both breeding and non-breeding populations is necessary.

With this communication during the first World Jackal Day on 19th April 2023 (https://www.goldschakal.at/gb/world-jackal-day/) we presented the preliminary results of our informal research project on the golden jackal behavioural ecology and reproductive biology in north-eastern Italy.

In the last decade, there has been a remarkable increase in the number of scientific publications on the ecology of the golden jackal Canis aureus , whereas information on its reproductive biology is still scanty, and the basic reproductive parameters of the species are not yet fully understood. In 2021, we began a research project in North-Eastern Italy, where the golden jackal is strictly protected under the National Law, to investigate the species behavioural ecology and reproductive biology at the den site, as a key element for defining conservation measures. Within this project, we documented allosuckling behaviour, possibly related to the breeding of two females within the same social unit, with den sharing and communal nursing of the cubs. Our observations open new scenarios and raise questions on the reproductive biology and social organisation of the golden jackal, stimulating further topics for research.

Purpose/Objective: For species listed in Annex V of Habitats Directive, EU Member States shall, if deemed necessary, take measures only because of surveillance work, to ensure that their exploitation is compatible with maintaining them in a favorable conservation status. However, game management plans are elaborated without specific data on local density, at official rates overpassing 90–100 % (i.e. Romania), while the main reproductive parameters of the species are not yet understood. Our aim was to investigate reproductive biology at the den site as a key element in defining lethal control policies or conservation measures. In Italy the species legal status is strictly protected. Material/Methods: The study area is located in NE Italy on the lower Isonzo River catchment. First, we calculated the density performing a preliminary survey combining bioacoustics monitoring method (Giannatos 2004) and jackal litters opportunistic occurrence with camera trapping. Afterwards, we monitored 24 potentially suitable burrows during 2021 and 2022 breeding seasons with IR sensor cameras. Results: The local density was 0.53–0.65 groups / 10 km2. One of the monitored burrows has been occupied by three adult jackals (one male, two females). In this site, one camera trap was active from 20/02/2022 to 30/06/2022, with 112 days of recordings and 18 days (four interruptions) without recording. 1814 videos of jackals were collected. Significant observations: 04/04 – last record of the dominant female pregnant; 09/04 – the dominant female brought inside the burrow 8 new-born jackals; 10/04 – a second female (helper) was observed at den site from this date; 26/04 – first den exit of a cub; 29/04 – the helper female appeared pregnant; 02/05 – the helper female was recorded allo-suckling from this date; 20/05 – the dominant female brought away from the den 3 inept new-born cubs, whom 10 min later were brought back inside by the helper. Later in the day, the dominant female moved away 4 new-borns; 21/05 – the helper female brought at least one new-born back into the den; 28/05 – jackals leaved the den. Conclusion: We documented the first case of multiple breeding and communal nursing within one group of golden jackals. The dominant female gave birth to 8 cubs between the 4th and 9th of April and the period between gestation and independent den exit was 17–22 days. The two females cooperated in rearing the first litter throughout the denning period (49 days). A second litter of 4 cubs appeared related to the same den, as result of parturition by the helper female. The birth of this litter occurred between the 29th of April and 2nd of May. Based on observations of threatening / aggressive behaviors from the male toward the helper, polygyny might be excluded. Apparently the second litter did not survived. Our findings open new scenarios and questions about the reproductive biology and applied ecology of C. aureus in areas with low density and low mortality.

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).