Commercial crustaceans from Chile and Perú: What do we know about their life-histories and how does ENSO affect them?

ASOREY, CYNTHIA; CALCAGNO JAVIER,; GUSTAVO ALEJANDRO LOVRICH

Concepción, Chile

Simposio; CENSOR Midterm Symposium; 2006

Universidad de Concepción, Alfred Wegener Institut

Along the East Pacific coast, crustaceans are one of the groups of organisms of which little isknown about their life-histories. This knowledge is basis of a sustainable shellfish managementunder normal and ENSO conditions, but little information is available about these topics. The aim ofthis work is to synthesize all information available on reproductive biology, fisheries, and ENSOeffects of several commercially exploited crustaceans available from the literature (in grey literatureand periodic publications) in Chile and Peru, in order to detect gaps and to elaborate a plan ofmanagement of these fisheries under both ENSO and non-ENSO conditions. In general, there aretwo types of effects according to the non-ENSO environment of the species. Species belonging totropical waters seem to be increasingly found further south during El Niño (EN), whilst in the caseof species belonging to the Humboldt current it is not well understood if they suffer from massmortality during EN or migrate into deeper waters. Paredes et al. (2004) reported that 15 speciesof crustaceans belonging to the Panamanian Province or to tropical oceanic waters movesouthward to the central or south coast off Peru. The migratory distance depends on the intensityof the EN phenomenon. Many of them are important commercial species, for example shrimpssuch as Xiphopenaeus riveti, Litopenaeus spp and Farfantepeneaeus californiensis. Regardingcold waters species, Arntz et al. (1988) reported that species of crabs such as Cancer setosus,Platyxanthus orbignyi and Emerita analoga died during strong EN event; while populations ofspecies like Cancer porteri survived in deeper waters. These works have been made upon fieldobservations of the landings in several ports and surveys done by Peruvian fishermen. On theother hand, there are no reports about cold event effects, La Niña (LN), on the aforementionedspecies. In a previous work, we wanted to know if Peruvian crustacean landings were related to thesea surface temperature (SST) registered at Chicama station (07° 41' S, 79° 26' W). We found apositive correlation between the total crustacean landings of Peruvian shrimp species and both theannual mean temperatures and the maximum temperatures. We also found a negative but nosignificant correlation, for the crab species (Cancer sp, Platyxanthus sp). But this first approachhad limitations like lacking of temperature data in each port and differentiation by species in thedata landing statistics.