Changes in Fish Communities of Lake Ontario Coastal Wetlands before and after Remedial Action Plans

Abstract EN

We conducted a change-detection analysis to determine if improvements in the habitat quality of coastal wetlands could be attributed to Remedial Action Plans (RAPs) of Lake Ontario.

We used a 5-km buffer relative to each recent site to “resample” an existing database of spawning/nursery habitat from the early 1980s to derive a “historic” species list associated with thirteen representative wetlands sampled in 2001-2002.

For each wetland, we calculated Wetland Fish Index (WFI) scores, which are relative measures of wetland quality having scores ranging from 1 to 5, indicating worst to best conditions, respectively.

The mean WFI score of 3.16 for the recent era was significantly higher than that for the historic era of 2.79 (Wilcoxon sign-rank test; P=.04), and this is consistent with the conclusion that lakewide RAPs have been effective in recovering some of the ecological functions of degraded coastal wetlands of Lake Ontario.