title: Gulls identified as major source of fecal pollution in coastal waters: a microbial source tracking study.
abstract: Gulls were reported as sources of fecal pollution in coastal environments and potential vectors of human infections. Microbial source tracking (MST) methods were rarely tested to identify this pollution origin. This study was conducted to ascertain the source of water fecal contamination in the Berlenga Island, Portugal. A total of 169 Escherichia coli isolates from human sewage, 423 isolates from gull feces and 334 water isolates were analyzed by BOX-PCR. An average correct classification of 79.3% was achieved. When an 85% similarity cutoff was applied 24% of water isolates were present in gull feces against 2.7% detected in sewage. Jackknifing resulted in 29.3% of water isolates classified as gull, and 10.8% classified as human. Results indicate that gulls constitute a major source of water contamination in the Berlenga Island. This study validated a methodology to differentiate human and gull fecal pollution sources in a real case of a contaminated beach.
authors.affiliation: Department of Biology, CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Susana
authors.initials: S
authors.lastname: Araújo
authors.affiliation: Department of Biology, CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal. Electronic address: ihenriques@ua.pt.
authors.forename: Isabel S
authors.initials: IS
authors.lastname: Henriques
authors.affiliation: GIRM, Marine Resources Research Group, School of Tourism and Maritime Technology, Polytechnic Institute of Leiria, Campus 4, 2520-641 Peniche, Portugal.
authors.forename: Sérgio Miguel
authors.initials: SM
authors.lastname: Leandro
authors.affiliation: Department of Biology, CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Artur
authors.initials: A
authors.lastname: Alves
authors.affiliation: Department of Biology, CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: Anabela
authors.initials: A
authors.lastname: Pereira
authors.affiliation: Department of Biology, CESAM, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
authors.forename: António
authors.initials: A
authors.lastname: Correia
mesh_terms: D000818:Animals; D046091:Charadriiformes / Q000502:physiology*; D004784:Environmental Monitoring; D004926:Escherichia coli / Q000254:growth & development / Q000302:isolation & purification; D005243:Feces; D011174:Portugal; D014871:Water Microbiology; D014876:Water Pollution / Q000032:analysis* / Q000706:statistics & numerical data
keywords: BOX-PCR; Escherichia coli; Fecal pollution; Gulls; Microbial source tracking; Public health