RSS![[Nameplate]](http://www.dickinsoncountynews.com/images/nameplate.png)
RSS
Print
Email link
Respond to editor
Read comments (1)
Now, a new threat has spawned and water protection groups are trying to prevent the invasion of another aquatic invasive species -- Asian silver carp, or "jumping fish."
The Dickinson County Board of Supervisors on Jan. 10 approved a motion to contribute over $3,000 to the study for installing an electric fish barrier to prevent the arrival of Asian carp in the Iowa Great Lakes. The carp were recently found in Lost Island Lake, just 15 miles from the Great Lakes.
Asian carp can grow up to 60 pounds and three feet long and are known for jumping high out of the water. Once the fish have invaded a well-trafficked lake, they can become great distractions to boaters, skiers and Jet Ski operators. Vibrations from the motors cause the fish to jump out of the water, potentially right in front of boats and skiers.
Extreme floods along the Missouri River in 2011 allowed carp to swim around the Linn Grove Dam and work their way toward the Dickinson County chain of lakes. The Asian Carp's cousin, bighead Asian carp, were actually found in East Lake Okoboji in August 2011.
As is the case with many invasive species, there is no proven way to remove the aquatic intruder once the lake has been infected.
The electric barrier is proposed on land already owned by the local DNR near the Lower Gar outlet. The Iowa Great Lakes Water Safety Council (WSC) considers this to be the best location. An electric barrier further downstream would potentially trap other fish and cause a pungent die-off between the weir and the barrier.
One of the most common inquiries of an electric barrier is the potential danger to animals and humans -- the charge isn't even strong enough to kill off the fish.
"At first, the fish feel a tingle they don't like, so they swim away," said Phil Petersen, secretary of the Iowa Great Lakes Water Safety Council. "If they continue, the voltage becomes more unpleasant. Eventually it will numb them. We don't believe it ever gets to point that it kills them."
Petersen also said that humans or other animals such as deer or dogs are not in danger of being killed.
"We don't believe the voltage used is enough to kill animals or people," he said. "But to be safe, it is standard operating procedure to place signs (warning) of electrical danger and (to) fence (off) the area.
Studies have shown that an electric fish barrier is an effective way to prevent a species from entering a lake. During a two-year study done by a research team from South Dakota State University in the early 1990s, 1,600 common carp and south buffalo fish were radio tagged and released downstream from an electric barrier. When they later caught over 3,000 fish, not a single one of the tagged fish were found.
In addition to preventing the intrusion of the invasive species, the electric barrier has another benefit -- it prevents other fish from leaving the lakes.
"A secondary benefit is that there are musky and walleye that are bred by the fish hatchery and they often tend to swim into the Little Sioux River," said Petersen said. "The barrier will keep them in the lakes."
Local officials estimate the cost of the project at $700,000. State Reps. John Wittneben of Estherville and Jeff Smith of Spirit Lake are working with state Sen. David Johnson of Ocheyedan to secure state funding for the project. The local Water Safety Council thinks at least $200,000 will need to be raised locally to support of the electric barrier project. The funds will come from the various lake protective associations, fishing businesses, local governments and property owners.
The DNR will need funds identified by March in order to move ahead with the project before the start of the 2012 vacation season.
"We would like to have it in place sometime in the spring," Petersen said. "It takes three to four months for the barrier to be installed. We are pretty confident it will work, we don't have much doubt."
Comments
Keeping the invasive species out of the Iowa Great Lakes is an important goal. It should be embraced as an important project for the community. However, there are many questions that need to be answered before a fish barrier is installed in the proposed location.
First, there is conflicting data from other sources that indicate the proposed electric fish barrier systems aren't 100% effective. They are proposing to spend a lot of money on the system, we better make sure it works first.
Second, Phil Petersen states, "We don't believe the voltage used is enough to kill animals or people," he said. "But to be safe, it is standard operating procedure to place signs (warning) of electrical danger and (to) fence (off) the area."
Young kids like to climb fences. Young kids don't always read signs or can't read signs if they are too young. Many kids and adults fish in the proposed area for the barrier that live in the area. Don't we need to be 100% sure these systems are safe? We shouldn't "believe" they are safe; we need to be absolutely sure they are safe.
Third, it seems like using an electric fish barrier system would cost less if it were used in a smaller confined area. Why try to install the barrier in the area of the Lower Gar weir that is a couple hundred feet wide? For example, why not install it on the down streamside of the culverts below Highway 71? Or on the downstream side of A34? These areas are more isolated for safety reasons, they are smaller, so the cost should be less.
Fourth, Phil Petersen states the systems should help keep the good fish we want in the lakes. However, the electric fish barrier systems work if the fish swim too close to the barrier. If the fish swim too close they will be shocked. Once shocked the fish are paralyzed, they can't swim, and they are washed down stream. This is how the electric fish barriers work. In times when the lake level is higher the current moves fast in that area, the good fish will be swept by the current into the barrier. The good fish will be shocked and swept out of the lakes. Remember, the electric barriers don't care what size of fish it is. The barriers will shock the small fish that eventually grow up to be larger fish. Small fish have more trouble swimming against the current. Would this electric fish barrier system reduce the future fish populations of the lakes?
Lastly, is the speed at which Phil Petersen wants to get this work completed. He wants to get the barrier in place sometime in the Spring. He states it takes three to four months for installation. If funds were secured by March, and work began immediately, the barrier would be done mid-summer, not in the Spring.
More of a concern is the comment Phil Petersen made at the meeting when he presented the proposed barrier when his comment is taken in context with the speed at which he wants to get this project done. He stated that, "the barrier might replace the weir." The weir is regulated by the State legislature. This would take some quick action by the legislature to change the weir. Dickinson County, the Milford City Council, the DNR, and concerned citizen's spent three years working on a solution to handle periods of high water in the lakes. The solution was to install two additional culverts above the Lower Gar weir to lower the lake quicker in periods of high water. This solution was not what a few West Lake residents wanted for a solution. During the Summer of 2011 the additional culverts performed as planned and the lake level was dropped very quickly as seen on the Iowa Great Lakes Water Safety Council's lake level data. However, those same proponents are still working to get the weir taken out and the 230th Ave. culverts replaced with a bridge. Concerned citizens, ALL people who live on or around the Lakes, need to pay attention to insure this small group of people, don't take this proposed fish barrier and turn it into a way to do long term damage to the lakes by getting the weir and culverts removed in the sake of keeping out the invasive species.