Wind-Forced ydrodynarnics and Their nteraction Fish and P ance: A Ti-Series An

We evaluated methods to measure simultaneously biological and physical properties essential for estimating short-term mortality of larval fish. We used the data to test Templeman's watermass exchange hypothesis and the associated safe-site hypothesis. Synoptic estimates of larval capelin (Mallstus villosus) and microzooplankton particle density were obtained simultaneously with a scale resolution of 200 m (horizontal), 2-4 m (vertical) and 6-8 k (temporal) in a 4-kmr coastal embayment in eastern Newfoundland. Statistically significant population estimates were derived from multiple regression models incorporating a limited number of samples. Spectral analysis of wind and current time-series and analysis of large-scale temperature oscillations were consistent with Templeman's hypothesis. Nearshore current respnded to cross-shore wind forcing at periods of 2-6 d. Larval capelin abundance oscillations were coherent with wind and with current at periods ot-5 dl consistent with the watermass exchange and safe-site hypotheses. Although larvae and microzooplan kton abundances showed similar spectra % density and were in phase, their coherence was weak. Integrated measures of onshare wind and of the onshore-c~ffshore wind spectrum were correlated, and either can be used as a composite measure of the considerable interannual variation evident in the frequency, magnitude, and duration sf onshore winds, and hence of watermass exchange. Afin de d6terminer la mortalit6 A court terme des larves de poisson, les auteurs ont 6valuk des m6thsdes d