Essential Market Squid (Doryteuthis opalescens) Embryo Habitat: A Baseline for Anticipated Ocean Climate Change

ABSTRACT The market squid Doryteuthis opalescens deposits embryo capsules onto the continental shelf from Baja California to southern Alaska, yet little is known about the environment of embryo habitat. This study provides a baseline of environmental data and insights on factors underlying site selection for embryo deposition off southern California, and defines current essential embryo habitat using (1) remotely operated vehicle–supported surveys of benthos and environmental variables, (2) SCUBA surveys, and (3) bottom measurements of T, S, pH, and O2. Here, embryo habitat is defined using embryo capsule density, capsule bed area, consistent bed footprint, and association with [O2] and pH (pCO2) on the shelf. Spatial variation in embryo capsule density and location appears dependent on environmental conditions, whereas the temporal pattern of year-round spawning is not. Embryos require [O2] greater than 160 µmol and pHT greater than 7.8. Temperature does not appear to be limiting (range: 9.9°C–15.5°C). D...