title: Gull-derived trace elements trigger small-scale contamination in a remote Mediterranean nature reserve.
abstract: The role of a yellow-legged gull (Larus michahellis) small colony in conveying trace elements (As, Cd, Cr, Cu, Ni, Pb, THg, V, Zn) was assessed in a Mediterranean nature reserve (Marinello ponds) at various spatial and temporal scales. Trace element concentrations in guano were high and seasonally variable. In contrast, contamination in the ponds was not influenced by season but showed strong spatial variability among ponds, according to the different guano input. Biogenic enrichment factor B confirmed the role of gulls in the release of trace elements through guano subsidies. In addition, comparing trace element pond concentrations to the US NOAA's SQGs, As, Cu and Ni showed contamination levels associated with possible negative biological effects. Thus, this study reflects the need to take seabirds into account as key factors influencing ecological processes and contamination levels even in remote areas, especially around the Mediterranean, where these birds are abundant but overlooked.
authors.affiliation: Department of Earth and Marine Sciences, University of Palermo, CoNISMa, via Archirafi 18, 90123 Palermo, Italy. Electronic address: geraldina.signa@unipa.it.
authors.forename: Geraldina
authors.initials: G
authors.lastname: Signa
authors.forename: Antonio
authors.initials: A
authors.lastname: Mazzola
authors.forename: Cecilia Doriana
authors.initials: CD
authors.lastname: Tramati
authors.forename: Salvatrice
authors.initials: S
authors.lastname: Vizzini
mesh_terms: D000818:Animals; D046091:Charadriiformes; D003247:Conservation of Natural Resources; D004784:Environmental Monitoring; D005243:Feces / Q000737:chemistry*; D019368:Nature; D014131:Trace Elements / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014131:Trace Elements; D014874:Water Pollutants, Chemical
keywords: Bioenrichment; Guano; Lagoon; Seabird; Stable isotope; Trace metals