SS1.09 Fisheries Population Linkage Spatial and Temporal Variation in Zooplankton
Date: Wednesday, June 12, 2002
Location: Poster Session - VCC
 
SnelgrovePV, Memorial University of Newfoundland, St. John's, Canada, 
 
SPATIO-TEMPORAL VARIATION IN ICHTHYOPLANKTON IN A LARGE NEWFOUNDLAND EMBAYMENT: LINKAGES TO ZOOPLANKTON
image
Gridded Tucker Trawl surveys in the spring and summer of 1997-1988 in Placentia Bay, a large Newfoundland embayment, demonstrate that ichthyoplankton exhibit strong variation in seasonal and spatial pattern. In order to determine whether zooplankton might contribute to ichthyoplankton variation, patterns in the two groups were compared within and among survey periods. Temporal comparisons among survey periods showed that zooplankton concentrations were significant predictors of ichthyoplankton concentrations, in that larval fish were most abundant at times when zooplankton were most abundant. Spatial comparisons within surveys showed that zooplankton was a significant predictor of ichthyoplankton only when the bay was most physically structured and ichthyoplankton and zooplankton were most spatially heterogeneous. During a given survey period, although ichthyoplankton exhibited greater spatial heterogeneity in community composition than zooplankton, zooplankton species composition was generally a highly significant predictor of ichthyoplankton species composition, suggesting a close spatial linkage between the two groups of organisms and a potentially strong regulatory role for zooplankton in ichthyoplankton pattern.