Control crews attack lamprey in Big Otter

[Spiel]

Control crews attack lamprey in Big Otter

 

 

May 30, 2008

Jeff Helsdon / tillsonburgnews.com

 

 

Big Otter Creek has been flowing green and mean the last couple of days if you are a sea lamprey.

 

Department of Fisheries and Oceans crews were in town to treat the Otter with TFM, a lamprey control chemical. The application of TFM turned the creek green.

 

Sea lamprey is an invasive species that colonized the upper Great Lakes over 50 years ago when the Welland Canal was deepened. The creatures attack fish, sucking blood and juices from them, which often is fatal. During the creature’s 12 to 18-month parasitic phase, one lamprey can destroy over 40 pounds of fish.

 

The sea lamprey control program is a joint effort between Canada and the United States.

 

Typically Lake Erie tributaries are treated every three years to keep lamprey numbers in check. Since lamprey numbers in Lake Erie are increasing, treatment in back-to-back years is being undertaken on all lamprey-producing tributaries. That list includes both Big Creek and the Big Otter.

 

Treatment in the Otter started Monday at midnight and needs to continue for 14 hours to be effective. TFM will kill lamprey larvae and adults. It is not fatal to fish as fish have an enzyme that allows them to metabolize chemical.

 

“If there is diseased fish in the river, or other compromised fish, there will be some kill, but it will be light,” said Brian Stephens, treatment supervising biologist with the Sea Lamprey Control Centre in Sault Ste. Marie. He said there would be some kill of invertebrates, but these creatures drift with the current and will repopulate from populations above the treated area.

 

During treatment, the crew of 28 people takes water samples to ensure the concentration is at the required level. Samples are processed at a portable laboratory based at Covey’s Super 8.

 

In addition, crew members in canoes ensure the TFM is effective and is killing the lamprey.

 

“They’re our eyes on the stream and can tell us we’re getting the level of kill we want,” Stephens said.

 

The technicians in canoes also use portable sprayers to treat backwater areas the main chemical flow misses. Stephens explained if the entire stream were not treated, the lamprey would swim to the untreated area to escape the chemical.

 

When sea lamprey hatch, the young are filter feeders and live in streams until they are three years old. After that age, the lamprey develops eyes and a mouth, become parasitic and migrates into the lake.

 

As part of the stepped-up effort, crews will treat all lamprey-producing tributaries again in fall 2009. Stephens explained by that time, any larvae from eggs laid in 2009 would be hatched and vulnerable to TFM.

 

In addition to TFM application, barrier dams also limit lamprey spawning. In this area, dams are located on the Little Otter, Normandale Creek and Clear Creek. Other local creeks being treated are Young’s Creek, south of Simcoe and Silver Creek, between Port Burwell and Port Bruce.