title: Long-term monitoring study of beached seabirds shows that chronic oil pollution in the southern North Sea has almost halted.
abstract: Trends in oil rates of beached seabirds reflect temporal and spatial patterns in chronic oil pollution at sea. We analysed a long-term dataset of systematic beached bird surveys along the Belgian North Sea coast during 1962-2015, where extreme high oil contamination rates and consequently high mortality rates of seabirds during the 1960s used to coincide with intensive ship traffic. In the 1960s, >90% of all swimming seabirds that washed ashore were contaminated with oil and estimated oil-induced mortality of seabirds was probably several times higher than natural mortality. More than 50years later oil rates of seabirds have dropped to historically low levels while shipping is still very intense, indicating that chronic oil pollution has significantly declined. The declining trend is discussed in the light of a series of legislative measures that were enacted in the North Sea region to reduce oil pollution.
authors.affiliation: Research Institute for Nature and Forest, Kliniekstraat 25, 1070 Brussels, Belgium. Electronic address: eric.stienen@inbo.be.
authors.forename: Eric W M
authors.initials: EWM
authors.lastname: Stienen
authors.affiliation: Research Institute for Nature and Forest, Kliniekstraat 25, 1070 Brussels, Belgium.
authors.forename: Wouter
authors.initials: W
authors.lastname: Courtens
authors.affiliation: Research Institute for Nature and Forest, Kliniekstraat 25, 1070 Brussels, Belgium.
authors.forename: Marc
authors.initials: M
authors.lastname: Van de Walle
authors.affiliation: Research Institute for Nature and Forest, Kliniekstraat 25, 1070 Brussels, Belgium.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Vanermen
authors.affiliation: Research Institute for Nature and Forest, Kliniekstraat 25, 1070 Brussels, Belgium.
authors.forename: Hilbran
authors.initials: H
authors.lastname: Verstraete
mesh_terms: D000818:Animals; D001717:Birds; D004784:Environmental Monitoring; D009659:North Sea; D059392:Petroleum Pollution / Q000032:analysis* / Q000331:legislation & jurisprudence; D012767:Ships; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical
keywords: Beached bird surveys; Long-term trend; Marine oil pollution; North Sea; Seabird mortality