Parasite communities were examined in Johnny Darters (Etheostoma nigrum) collected from five localities in the St. Lawrence River in southwestern Quebec: two reference localities, one polluted locality upstream of the Island of Montreal and downstream of industrial and agricultural activity, and two polluted localities downstream of the Island of Montreal in the plume from the wastewater treatment facility. Fish from the upstream polluted locality had the highest parasite species richness and total parasite numbers, and fish from the downstream polluted localities the lowest. Differences between reference and polluted localities were mainly due to higher abundances of the brain-encysting trematode, Ornithodiplostomum sp., at the reference localities. Differences between upstream and downstream polluted localities were mainly due to a higher diversity and abundance of trematodes in fish at the upstream locality
Supplemental Information
The St. Lawrence Action Plan (SLAP) 2011 to 2026 (see http://planstlaurent.qc.ca/en/home.html) is the latest Canada-Quebec Agreement on the St. Lawrence and builds on the four previous agreements implemented since 1988.
The agreement aims to conserve and enhance the St. Lawrence. It is based on strong collaboration and the pooling of resources and expertise between the governments of Canada and Quebec. As part of their respective responsibilities for the management of the St. Lawrence basin, these two governments recognize the need for close cooperation to tackle the environmental challenges facing this important ecosystem. Other partners are also joining in this initiative, including local organizations, environmental groups, research centres, and universities.
For more information on SLAP, please visit https://www.canada.ca/en/environment-climate-change/services/environmental-funding/ecosystem-initiatives/st-lawrence-action-plan.html