Search for endangered Atlantic whitefish comes up empty in Dartmouth lake
Anderson Lake stocked with thousands of rare fish, but few survived after breeding program cut
Federal scientists are searching a lake in Dartmouth, N.S., to determine the fate of an endangered fish species released there four years ago under a captive breeding program shut down by the Conservative government.
The endangered Atlantic whitefish, an ancient relative of the Atlantic salmon, was introduced into Anderson Lake as part of a captive breeding program cancelled in 2012.
Two floating traps have been installed on Anderson Lake to see if any fish survived — but so far the prospects aren't good.
"We're not seeing any fish, unfortunately," said Department of Fisheries and Oceans biologist Mark Showell after checking the traps for a fourth time in November.
Thousands released, few survived
From 2005 to 2012, the department released thousands of Atlantic whitefish reared in a captive breeding program into Anderson Lake. The department hoped the species would establish itself in the lake, which is at the Bedford ammunition depot on Magazine Hill. However, there is no indication it has worked.
Showell says 5,000 juveniles and 7,000 larval whitefish were released. When the captive breeding program was shut down, the remaining 500 adult brood stock were released into Anderson Lake.
Since 2012, the situation has gotten worse for the Atlantic whitefish.
The Petite Riviere watershed outside Bridgewater holds the last wild population. It's made up of Hebb, Millipsigate and Minamkeke lakes. At least two of the lakes have been invaded by small mouth bass and the chain pickerel, which both cause problems for whitefish. Trap nets set in Hebb Lake in October captured one chain pickerel, but no whitefish.
No adult Atlantic whitefish have been seen in the Petite Riviere watershed since 2014, but they did capture 54 juveniles in the spring.
Bleak prospects
"Eventually they will get old and they will all die. There is really no source to keep stocking this lake. The abundance in their natural lakes in the Petite Reviere system is very low there. It's unlikely we would ever take any from there and bring them here," Showell said.
Rod Bradford, Showell's predecessor at DFO, gave a bleak picture in a 2015 report.
"No Atlantic whitefish that would be the result of spawning in the lake were observed. Losses of stocked juveniles from predation and perhaps starvation appeared to be high," Bradford said.
The Harper government argued the Anderson Lake project justified the closure of the Mersey Biodiversity Centre, which housed the whitefish captive breeding program. The breeding program was part of Ottawa's recovery plan for the whitefish.