Update on Research in the Huron-Erie Channel
U.S. Geological
Survey, Great Lakes Science Center, Ann Arbor, Michigan, USA.
Since 1999, all 16 reputed historic lake sturgeon spawning grounds in the St. Clair and Detroit Rivers have been surveyed and characterized with side-scan sonar, underwater TV, and limnologic measurements during the spawning period. Two reputed sites in the St. Clair River are active, known sturgeon spawning sites. However, few, if any, of the reputed spawning sites in the Detroit River possessed enough void space to incubate sturgeon eggs successfully. About 40 other potential sturgeon spawning sites in the Detroit River were therefore examined and characterized, including Gabriel Richard Park near Belle Isle where clean sturgeon spawning habitat, consisting of coal cinders, metamorphic coarse gravel and cobble, and limestone "shot rock", will be constructed in February-March 2003, with funds from the Great Lakes Fishery Trust and the Coastal Zone Protection Grant program and the Michigan Dept. of Environmental Quality.
During 2000-2002, in collaboration with the Alpena FRO, Central Michigan University, and the University of Georgia, over 85 lake sturgeon were caught on set lines, 20 of which were implanted with ultrasonic transmitters and tracked with telemetry. One active lake sturgeon spawning site was found near Zug Island in 2001, where fish spawned over a bed of coal cinders. Owing to a large oil spill in the Detroit River in early April 2002, no sturgeon eggs were collected at the known spawning site or at two other, suspected spawning sites.