Atlantic Sturgeon Behaviour in a Marine Macrotidal Environment: Archival and Acoustic Telemetry Data from Minas Basin, Bay of Fundy

Wednesday, August 20, 2014: 10:30 AM
2104A (Centre des congrès de Québec // Québec City Convention Centre)
Jeffrey W. Beardsall , Biology, Acadia University, Wolfville, NS, Canada
M.J.W. Stokesbury , Biology, Acadia University, Wolfville, NS, Canada
Michael J. Dadswell , Department of Biology, Acadia University, Wolfville, NS, Canada
Adult Atlantic Sturgeon embark on coastal marine migrations; Canadian and American stocks aggregate in Minas Basin (45.28 N, 64.18 W), Bay of Fundy during summer months, but very little is known about how they occupy and navigate this extreme macrotidal environment.  Nine pop-up satellite archival tags (PSATs) provided depth and temperature measurements between July 8th 2011 and August 4th 2013 from Atlantic Sturgeon captured, tagged and released in Minas Basin.  Sturgeon tagged in Minas Basin spent > 90% of their time during June to August in <10 m, but during September and October they departed the Basin and depths ranged from <10 m - 120 m.  October to April depth occupancies in the Bay of Fundy ranged from 40 m to 100 m.  Atlantic Sturgeon depth records were clearly associated with tidal cycles; tides are an important factor influencing Atlantic Sturgeon feeding and migration behaviour in macrotidal environments.  Combined acoustic telemetry and PSAT data suggest Atlantic Sturgeon use selective tidal stream transport to navigate tidal currents up to 6 ms-1.  These are among the first detailed descriptions of Atlantic Sturgeon marine depth distribution from an extreme macrotidal environment in the northern part of their range.