Neglecting rivers affects health of Lake Simcoe

Ministry to poison brook
Scientists take drastic measures to stop spread of round goby into Lake Simcoe

Oct 13, 2005



Provincial scientists are going to poison a five-kilometre stretch of Pefferlaw Brook next week to kill the round goby.
Representatives from the Ministry of Natural Resources at a public meeting last week revealed they will take the unprecedented measure to prevent the spread of the foreign invading fish into Lake Simcoe, where it could devastate the $200-million recreational fishery.

They will use the pesticide Rotenone to kill all gill-breathing species in the river, but remove as many native fish as possible beforehand by using a stunning electroshock and transfer them out of the treatment area. Cages holding fish will be monitored during the treatment period to ensure there is a 100-per-cent kill rate, the audience was told.

Electroshock is not effective to remove gobies because they do not have a swim bladder and will not float to the surface.

Ministry scientist Peter Waring said other options to eradicate the round goby, first found in the river last year, were considered, but the use of Rotenone was the only effective one.

The voracious invader "has got a number of things that scare the hell out of me, quite frankly. This is not like anything we have in this part of the world," Mr. Waring explained.

Since being discovered below the dam last year, gobies have since been found near the mouth of Pefferlaw Brook within sight of the lake.

Mr. Waring warned if action isn't taken, the goby will be in the lake next year and beyond any control measures.

Other species, fowl and wildlife are not affected and there is no danger to human beings, although residents were cautioned to stay off the water. Boaters who have to use the river will be escorted by conservation officers.

The river is home to three major marinas, part of the Peninsula Resort, the Church of the Nazarene camp and many homes with personal docks. The lake, just off the mouth of the river, attracts thousands of American anglers every year.

The cost of the Rotenone alone will be at least $50,000.

The chemical will be applied by specialists from the department of Fisheries and Oceans tentatively starting Monday and lasting two to three days.

Between 80 and 90 per cent of fish are