Researchers from the Doñana Biological Station assessed the spatial variation in concentrations of ten metals in faeces of the lesser black-backed gull (Larus fuscus) wintering at seven localities in South-West Spain. They found high concentrations of metals in gull faeces, with several elements (arsenic, copper, molybdenum, lead and zinc) locally exceeding (by 2 to 11 times) derived Lowest Effect Level (LEL) values.

Research into the dispersal of plants lacking a fleshy fruit by avian endozoochory remains limited, particularly regarding the different roles of specific vectors in the same habitat. Plants dispersed by endozoochory were compared between two migratory waterbirds differing in body size: the lesser black-backed gull, and the white stork. Faeces and pellets were collected from roosting flocks on dykes in the Doñana rice fields, and extracted intact seeds. 424 intact seeds from 21 plant taxa...