Beached seabirds in Coquimbo Bay, northern Chile: What species and how many die?

Abstract

Monitoring of seabirds stranded on beaches can provide information about their causes of death, such as bycatch in fishing activities or oil spills. During a year we monthly monitored the Coquimbo Bay, north Chile, to quantify the number of seabirds and species stranded. We found 395 dead seabirds, of which 382 were identified and grouped into 21 species. The most abundant were the Peruvian booby with 115 individuals (30%), the Guanay cormorant with 83 individuals (22%) and the Kelp gull with 65 individuals (17%). The most abundant and frequent species were those nesting in the Coastal System of Coquimbo. Mortality mainly affected seabirds that feed on anchoveta, which is the main target resource of purse seine fishing. We suggest that the incidental mortality caused by fishing is chronic and relatively constant during the year. A long-term monitoring program is needed to better estimate the mortality and the factors that influence the interaction of seabirds with fishing gears.