Lake Ontario Joint Lake Trout Survey

The second set is made at the depth where the 10°C isotherm intersects within 2–3 metres off bottom. In years with only 4 sets per transect, 10°C is the target bottom temperature of the first gillnet set. Subsequent sets are made at 10 metre bottom depth intervals, along the transect.

For example, if 10°C is encountered at a bottom depth of 36 metres, then nets will be set at 36, 46, and 56 and 66 metres. A gillnet set is comprised of a single gang of 9, 15.2 metre monofilament multi-mesh panels of 51, 64, 78, 89, 102, 114, 127, 140 and 152 millimetre mesh. Data from the Lake Ontario and Bay of Quinte Fish Community Index Gillnetting (LOA_IA24_GL1) Eastern Basin deep sites (EB01-EB06) will be shared with this program to extend its geographic reach.

Update: Due to logistical and technical complications, USGS was unable to sample the Toronto, Bronte and Grimsby transects as planned. No data was collected for these sites in 2024.