The Remedial Action Plan currently lists fish populations as degraded or “impaired” in Thunder Bay on Lake Superior but Eric Berglund told Sept. 21st meeting participants that populations of lake trout and whitefish in Thunder Bay are healthy and comparable to populations across the broader lake. He said that data and populations trends for sturgeon, walleye and brook trout were much harder to quantify because populations of these fish were low, just as they were across the entire lake. He pointed out that it was difficult to compare Thunder Bay walleye populations, to either Black Bay or Nipigon Bay populations, where he said there was much better habitat for these fish. He added that longer term trends are difficult to measure since historical commercial fishing data, when compared to data collected using modern methods, does not provide an accurate picture of populations trends.
Eric’s presentation covered trends in abundance, diversity of species, population structure (juvenile abundance, recruitment, growth, mortality, exploitation) and data about natural reproduction. His presentation focused primarily on lake trout, lake whitefish, lake sturgeon, walleye and brook trout. Data was collected through the fish community index netting program of the Upper Great Lakes Management Unit of the Ontario Ministry of Natural Resources and Forestry. This program uses various mesh sizes at various depths with the objective of netting a representative sample of the fish community. Netting was done at multiple locations across Thunder Bay from the vicinity of Pie Island, also around the Welcome Islands, closer to the breakwall around Thunder Bay Harbour, east to locations like Caribou Island and Bay’s End at the base of the Sibley Peninsula, and south along the Sibley Peninsula to Thunder Cape.
For PAC members, the objective of the meeting was to learn about the health of Thunder Bay fish populations, especially in comparison to conditions across the lake as a whole. Additionally, based on this information, PAC input was sought as to whether the designation for fish populations should be changed to “unimpaired.” Other Thunder Bay ecosystem impairments include advisories for swimming at Chippewa Beach due to bacterial contamination, loss of fish habitat, and issues related to contaminated sediment, especially near the former Cascades mill not far from the mouth of the Current River.
Public Advisory Committee members asked if salmon were included in the study. Eric replied that they were not and that the emphasis was on native species. He said that salmon are rarely caught in the community index netting program. Public Advisory Committees members agreed that given the healthy populations of some species, the threshold had probably been met to remove the designation of “impaired” for these more populous species. They hesitated to provide support for overall removal of the impaired designation for all species however, as information was quite limited for some species. Members also noted the lack of data for fish populations inside the Thunder Bay breakwall. They said this lack of data had also been noted in a previous report. The committee decided they would continue discussion of fish populations at a future meeting. They said that even while further discussion was probably warranted for the designation of “impaired” for overall fish populations, agreement could likely be arrived at to remove several individual species from the impaired list.
PAC members agreed with Eric’s contention that in future, discussion, efforts and resources would be more productive if focused on increasing fish habitat. Eric’s presentation asserted that increased quantity and quality of fish habitat was one of the few ways of increasing populations of fish species such as walleye.
Gene Kent of the Lakehead Region Conservation Authority also provided a presentation about summer work done at the Mission Island Conservation Area, also work to protect and improve water quality in the Slate River Valley and efforts to survey area wetlands in both the McVicar Creek and McIntyre River Watersheds.
- Presentation on Thunder Bay fish populations given by Eric Berglund of MNRF
- The Public Advisory Committee previously agreed upon delisting criteria for fish populations which, if met, would assist in determining whether Thunder Bay fish populations have recovered to the extent that status of this item should be changed to “unimpaired.”
- Presentation of Gene Kent of the LRCA re Slate River and area wetlands
- Meeting agenda
- Minutes of the June 1, 2016 Thunder Bay PAC meeting.