DISTRIBUTION AND ECOLOGY OF MYSIDS IN CAPE COD BAY, MASSACHUSETTS

¹ Southern California Ocean Studies Consortium, California State University, Long Beach, CA 90840

Seven species of mysids (Neomysis americana, Erythrops erythropthalma, Mysis stenolepis, Mysis mixta, Heteromysis formosa, Praunus flexuosus, and Meterythrops robusta) were collected from Cape Cod Bay, Massachusetts. The general ecology of the first four species is described in terms of several classificatory schemes proposed for worldwide mysid distributions.

Organismal relationships to geographic, seasonal, bathymetric, bottom water temperature, and sediment characteristics are examined. Four species occurred year-round with the following seasonal peaks in abundance: N. americana (February, April, December), E. erythropthalma (January, March, December), M. mixta (March and July), M. stenolepis (January and August). Based on bathymetric and sedimentary relationships the species tend to occur in pairs. Neomysis americana and M. stenolepis were primarily collected in shallow water (10-29 m) and from sand and clayey-silt. Erythrops erythropthalma and M. mixta occurred in deeper water (20-39 m) and on clayey-silt and silt. In addition to seasonal effects, evidence indicates that interactions among depth, bottom water temperature, and sediment type strongly influenced the spatial zonation of Cape Cod mysids. The distribution and ecology of the four mysids generally conformed to worldwide classification schemes.