Monitoring of the yellow‑legged gulls Larus michahellis urban population

Monitoring of the Yellow-legged gulls Larus michahellis urban population in the historic centre of Venice and study of the effects of the new waste collection policy on the species

The project, developed over 24 months, from March 2017 to February 2019, has been financed by the public waste management company of Venice (Veritas S.p.a.)

In recent years the ability of yellow-legged gull to break the garbage bags left by residents and tourists on the street, by spreading their contents on the ground and in the city’s canals, to eat the leftovers of food has been widely documented in Venice. To counter such problems and limit the amount of trophic resources available to the species, the Venice Municipalized Company, starting from 2016, introduced a new door-to-door garbage collection system and garbage self-disposal to temporary waste disposal stations located on boats moored in specific areas of the city. Such new policy has been introduced in the six districts of the city at different times to allow residents to adapt gradually to the new directive.

The project aims at studying the effects of the new policy on the species abundance and distribution as well as to provide an updated estimate of the urban population in the historic center of Venice. To achieve these targets, we performed a monitoring program of the urban population of yellow-legged gulls between March 2017 and November 2018, using the Distance sampling technique (Buckland et al. 2001, 2015). Monitoring allowed us to document both the state before and after the introduction of the new policy and indicated the presence of more than 400 pairs in June 2018, against the 24 registered in 2005 (Soldatini and Mainardi, 2006). Importantly, following the policy change, we recorded a significant decrease of the urban waste in the streets as well as of the abundance of gulls feeding (Coccon and Fano, 2020) and breeding (Coccon et al, 2021) in the city. Individuals are now more concentrated in open areas, strongly frequented, with food and beverage vendors and illegal dumps. Such information is necessary for a proper management plan of the species based on a up-to-date and detailed knowledge of this urban species.

Project Brochure

"Effects of a new waste collection policy on the population of yellow-legged gulls, Larus michahellis", in the historic centre of Venice (Italy)", scientific article published on European Journal of Wildlife Research

"The abundance of yellow-legged gulls Larus michahellis breeding in the historic centre of Venice, Italy and the initial effects of the new waste collection policy on the population", scientific article published on Urban Ecosystems

Scientific manager: dott.ssa Francesca Coccon

Researchers: Francesca Coccon, Lucio Panzarin

For further information, please write to coccon@corila.it