The Engraulis ringens distribution (4 to 42°S) covers a wide variety of environmental conditions. We assessed the coping mechanisms used by this anchoveta in different spawning habitats, reporting differences in egg traits between populations off northern (Iquique, 20°S) and southern Chile (Talcahuano, 36°S) and throughout the spawning season. Eggs were smaller off Iquique, declined in size during the reproductive season (both populations), and inter-population differences persisted throughout the spawning season. Batch fecundity (eggs per batch per female) and relative fecundity (eggs per female weight) were lower off Talcahuano during the peak spawning months. Thus, larger eggs spawned in the southern population seem to be produced at the cost of a reduction in fecundity. The eggs also differed biochemically between the 2 populations; total lipids and triacylglycerides were much higher off Talcahuano. The biochemical composition (both populations) also changed throughout the spawning season, with higher lipids early in the spawning season (July to August) off Talcahuano. Hatching success decreased during the spawning season, and correlated positively with egg size and lipid contents. Environmental conditions differed markedly between spawning areas and from mid-winter to late spring. Off Talcahuano, the temperature and winter-time water column productivity are lower and turbulence is higher, while eggs are larger, lipid contents higher, and batch fecundity lower. This mechanism seems to facilitate survival of young offspring in the more adverse winter conditions off Talcahuano. These egg characteristics are determined by the adult female reproductive system, representing a maternal influence on the early life-history traits of anchoveta that might enable rapid changes in population densities in some years of improved habitat conditions. KEY WORDS: Anchoveta · Engraulis ringens · Upwelling · Reproductive strategy · Egg quality · Lipids · Humboldt Current · Small pelagic fishes Resale or republication not permitted without written consent of the publisher

A spatial description of the operational interaction between southern sea lions and jack mackerel fishing fleet off Central Chile is presented. The descriptive analysis showed a similar spatial trend for the number of sea lions per haul and catch per haul, both increasing in the SE direction, and decreasing in the NW direction. The number of sea lions was positively correlated with catches at intermediate distances from land, while negatively correlated with the number of fishing vessels at the greatest distance from the land. The geostatistical analyses corroborate the trends found during the descriptive analysis: 2 nuclei of high abundance of sea lions were found, which spatially overlapped 2 nuclei of high jack mackerel catches; nuclei that we proposed here as hot-spots for this interaction. Both hot-spots were located on the continental slope and over the deep ocean bed. No spatial relation was found between the number of sea lions and the number of fishing vessels. Thus, it is proposed that the area enclosed between 38-40°S and 74-75°30' W constitutes the sector of higher interaction between the southern sea lions and jack mackerel industrial fishing fleet.

We assessed the fatty acid (FA) composition of anchoveta eggs collected from the plankton along with female anchoveta reproductive traits and environmental conditions during peak winter spawning in 2005 and 2007. Environmental conditions differed markedly between years at 3 continental shelf stations off Talcahuano, Chile, with a warmer, fresher water column in 2005 and a colder, saltier one in 2007. We confirmed differences in sea surface temperature, measured both at the coastal egg collection stations and using satellite images over a broader area, caused by south

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