It seems residents concerned about the invasion of Illinois pondweed in Lake June-In-Winter will soon see another tool in the war against the pesky water weed. Sterile carp will likely be released into the big lake soon as one part of a bigger scheme.
We’re glad to hear the Florida Fish and Wildlife Conservation Commission has reversed course after initially rejecting the idea of using sterile carp. We asked for a “middle ground” in a September editorial and that middle ground appears to be here.
If all goes according to hopes, the carp will eat the pondweed and help keep in check its spread. That would be a significant help as lake users and lakefront property owners deal with the frustrations brought by the weed: clogged boat propellers, jammed intakes on personal water craft, and a danger to swimmers and skiers.
But we are reminded by FWC biologist Kelle Sullivan that these are uncertain waters, so to speak. There is no scientific proof that sterile carp will eat Illinois pondweed. But it is known that carp will eat. With ferocious appetities they will eat.
While hopes ride on the carp devouring Illinois pondweed, Sullivan cautions they might eat everything except the intended meal. She concedes FWC has no prior experience with carp as a mean of controlling Illinois pondweed, so little data is available.
What is known, Sullivan said, it that carp are timid and not likely to “graze” near docks, backyard beaches and anywhere else people are likely to frequent. She predicts many of the carp will make their way to quiet areas of the lake, most likely along the shoreline of Lake June Scrub Park on the western end of the lake.
Lakeside resident Mike Whitaker, who knows the lake like the back of his hand, has a different vision that he likens to a landlubber’s weed control problem. Imagine the lake as a huge field of grass that has grown out of control. You could mow it — or apply herbicides as the state is currently doing the battle pondweed — or you put grazing livestock on the property to keep the weeds in check.
Whitaker sees the sterile carp as the livestock in this scenerio. The carp won’t devour the plant and its roots, eventually removing it from the lake. The fish would keep the pondweed “mowed back” at controllable levels, he says.
It’s another check mark in the “good news column” that sterile carp are vegeterian and do not eat or harass other fish. Sterile carp go into the lake as fingerlings and eat their way to weights of 25 to 30 pounds within three to four years.
The fish have an average lifespan of about 10 years, Sullivan said, but after the fourth year or so the fish has gotten big, its metabolism is slowed, and it is no longer the weed eating monster it had been. What becomes of the fish when they become big and lumbering? The assumption is they become easy prey for alligators.
Sullivan says the herbicide applications are working. High resolution charts of the lake show a smaller footprint of Illinois pondweed since the effort began. Some lakefront property owners challenge that assertion, saying pondweed continues to sprout in new areas while the existing patches become more dense. The combination of herbicide and sterile carp could be the solution — or could be the start of a new problem. Time will tell.
Illinois pondweed will continue to be a hot topic. But we see it as a positive — a strong positive — that both sides in the issue seem to be listening to one another.