|Title||The influence of the El Nino Southern Oscillation on paralarval market squid (Doryteuthis opalescens)|
|Publication Type||Journal Article|
|Year of Publication||2016|
|Authors||Perretti CT, Sedarat M.|
|Type of Article||Article|
|Keywords||abundance; california bight; cephalopods; Critical Period Hypothesis; Doryteuthis; fishery; growth; hypothesis; larvae; life-cycle; loligo-opalescens; mortality; population dynamics; temperature; vulgaris|
California market squid (Doryteuthis opalescens) support one of the largest and most valuable fisheries in California. However, market squid abundance varies greatly from year to year, ostensibly as a result of the El Nino Southern Oscillation (ENSO) phenomenon, although the underlying mechanism is not known. Classic hypotheses suggest that the early larval stage may be the key to uncovering this mechanism. Here, we perform a time series analysis, length-distribution analysis, and growth analysis to investigate the effects of ENSO on paralarval D.opalescens. In contrast to classic hypotheses, we find that ENSO does not drive early paralarval survival or growth. Instead, we find that the ENSO operates primarily on the late paralarval stage, with El Nino conditions associated with lower survival of late-stage paralarvae. We also find that time series models which use ENSO conditions during the previous juvenile and adult stage outperform models that use ENSO conditions during the paralarval stage. Our results suggest that the population bottleneck for D.opalescens does not occur in the early paralarval stage, but instead lies later in the squid's life.
|Short Title||Fish Oceanogr.|