Temporal trends of plastic ingestion and fishing gear entanglement in aquatic birds from Portugal

• Autor(a) principal: Rao, Silvia
• Data de Publicação: 2020
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.1/15613
• topic: Lixo antropogênico; Ingestão de plástico; Emaranhados de artes de pesca; Aves; Portugal

Improperly disposed anthropogenic litter and fishing material acutely affect wildlife species in the terrestrial and aquatic ecosystems. The foraging behaviour of birds makes them suitable to monitor changes of anthropogenic litter over time in the environment. The general aim of the thesis is to quantify and qualify species-specific changes over time due to anthropogenic litter ingestion and fishing gear entanglements. In Chapter 2, the specific objective was to test for temporal changes of anthropogenic litter ingestion in aquatic and marine birds in southern Portugal. Across the seven years (2014-2020) and out of the four bird species (total sample size of 462) analysed, Ciconia ciconia had the highest frequency of occurrence (61.1%), followed by Larus fuscus (20.8%), Morus bassanus (20.3%) and Larus michahellis (13.4%). In all species, User plastics (plastic category) was the most abundant type of material ingested and white/off clear was the predominant ingested colour. In Chapter 3, the aim intent was to test for temporal trends in fishing gear entanglements in aquatic and marine bird species over a ten year period (2010 - 2019). Of the 5843 individuals processed, 256 were affected either by fishing nets, fishing lines with or without hook. Phalacrocorax carbo showed a significant decrease in entanglements, whereas Morus bassanus showed the opposite pattern. Our findings provided an overview on temporal litter ingestion and entanglements on bird species in southern Portugal.