Dower, J. F.. University of British Columbia, dower@eos.ubc.ca
Pepin, P. F.. Fisheries & Oceans,
Leggett, W. C.. Queen's University,

 
MESO-SCALE PATTERNS OF FEEDING AND GROWTH OF LARVAL FISH IN COASTAL NEWFOUNDLAND AS A FUNCTION OF TURBULENCE AND PREY AVAILABILITY
 
Small-scale mixing and turbulence can increase feeding success in larval fish. In addition, previous field work on Conception Bay has demonstrated that larval radiated shanny (Ulvaria subbifurcata) change their feeding patterns and selectivity in response to increased turbulence. Here we report results from a second survey in which we explore whether mesoscale patterns in mixing and turbulence produce corresponding patterns in larval fish feeding and growth. Field work was conducted in coastal Newfoundland during July/August 1997. Larval Ulvaria were collected four times a day in each of three adjacent bays using a 2x2 m Tucker trawl while following a drifting buoy drogued to 20 metres depth. Zooplankton samples were collected using a 70 micron mesh ring-net. A CTD and an ADCP were used to characterize the hydrographic structure and current and velocity fields around the drifter. Gut and otolith analyses were performed on about 400 Ulvaria larvae ranging in size from 4-19 mm. Larval feeding and growth rates varied as a function of time of day and also between bays. This presentation will examine the contribution of between-bay differences in turbulence and prey availability to the observed patterns in larval feeding and growth.
 
Day: Tuesday, Feb. 2
Time: 04:15 - 04:30pm
Location: Hilton of Santa Fe
 
Code: SS01TU0415H