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El Niño induced changes of the coastal fish fauna off northern Chile and implications for ichthyogeographywere typical for sandy beaches and 14.6% for rocky shores. The shore fish community did not show major changes during and after EN events, as only a few invading species were recorded; just Umbrina xantii was found during all events considered. In order to understand the response of the fish community to ENSO events a biogeographical analyses of 721 fish species reported for neritic habitats (coastal epipelagic and benthic) distributed between 0°-57°S (Gulf of Guayaquil to Cape Horn) was made. Their distribution ranges for normal oceanic conditions were taken from the very numereous existing literature. It is concluded that the north/south migration of Panamic and Peruvian warm water fishes during EN/LN events along the north Chilean coast between 18º-23ºS, indicates that it represents a wide transition zone between the Peruvian and the Chilean ichthyogeographic provinces. Key words: ENSO, neritic fishes, northern Chile, ichthyogeographyResumen.-La franja costera de la zona norte de Chile (18º-23ºS) es habitada por numerosas especies de peces neríticos de las cuales 249 son comúnmente observadas durante condiciones normales y condiciones frías La Niña (LN). Durante El Niño (EN) la ictiofauna del norte de Chile experimenta cambios significativos a causa de la presencia de alrededor de 100 especies de peces invasores que durante periodos normales y/o fríos habitan en latitudes menores, siendo también nombrados "invasores septentrionales" y "peces trópico-ecuatoriales". Este conjunto incluye 15 familias y 86 géneros de peces. Los análisis mostraron que las especies afectadas por los EN no fueron las mismas durante los últimos tres eventos, revelando que solo las especies epipelágicas Anchoa naso, Albula vulpes, Atherinella nocturna y Scomberesox saurus stolatus fueron constantes. Frente al norte de Chile, durante los EN

Goetz, S., Wolff, M., Stotz, W., and Villegas, M. J. 2008. Interactions between the South American sea lion (Otaria flavescens) and the artisanal fishery off Coquimbo, northern Chile. – ICES Journal of Marine Science, 65: 1739–1746. The South American sea lion (Otaria flavescens) forages in coastal waters, where it interacts with fisheries and causes considerable economic loss by removing some catch and damaging gear. This study describes for the fishery region of Coquimbo (Chile) where, when, and with what type of gear interactions occur, characterizes the animals involved (group size, sex, and age), and derives some management recommendations. The study was based on 55 interviews with fishers and observations aboard fishing vessels in the main fishing sectors between October 2003 and March 2004. Interactions were primarily at night (88% of interviewees fished at night), in the bay (“Bahía”) of Coquimbo (81% of interviewees fished in this sector), where shoaling fish were abundant, and with purse-seines (100% of interviewees used this gear). Although some large groups of sea lions were seen, most comprised 1–10 animals. Most animals that interacted with the fishing gear were males (67%), probably because of the different feeding strategies of the two sexes. Management options discussed include the adjustment of fisheries to foraging behaviour of sea lions, and the controlled elimination of conflicting animals.

The marine otter Lontra felina has been said to prefer wave-exposed habitats over more protected sites in response to a greater prey abundance in exposed habitat. We examined how the foraging activity of L. felina is affected by the regime of wave exposure and prey availability at Isla Choros, northern Chile. Through focal sampling we recorded time spent by otters in foraging, the duration of dives, and the hunting success on a wave-exposed and a wave-protected site on the island. In addition, we quantified the abundance of prey in both habitats. Marine otters spent more time foraging in the wave-protected site compared with the wave-exposed habitat. Successful dives reached 26.9% in the wave-exposed habitats, and 38.2% in the wave-protected habitat. Foraging dives were 18% shorter in wave-exposed as compared with wave-protected habitat. Numerically, available prey did not differ significantly with habitat. Our results are more consistent with the hypothesis that wave-exposed habitats represent a sub-optimal habitat to foraging marine otters. Marine otters' use of wave-exposed patches through northern and central Chile coastal areas probably reflects a low availability of suitable protected areas and greater human disturbance of more protected habitat.