Lake Weed Management

In 2014 Vause Lake was diagnosed as having a severe "weed management issue".  Concerned homeowners asked for the help of Florida Lake Watch, Florida Fish & Wildlife Commission (FWC) and other experts to analyze the condition of Vause Lake and to make a recommendation as to a solution to the increasing weed problem. 

 

The concensus recommendation was to introduce a limited number of "triploid" (sterilzed) carp into Vause Lake in order to provide a "natural" and controlled management solution to weed growth.  As per the recommendation, concerned homeowners filed for and were granted a Florida State permit to purchase and introduce 100 carp into Vause Lake.  The "100" number was based upon the concensus "one fish per acre" conservative estimate; each fish to be from 10 in. to 12 in. in length.  The carp were placed into the lake early Feb 2015.  The progress of the "carp project" is being monitored by FWC and Dr. Ed Hauser, an expert in Environmental Science, kindly provided by the Luther Springs Organization which is a major land owner on Vause Lake.

 

As the "Carp Project" progresses, periodic evaluations will be made as to its effectiveness and the need to increase the carp population if deemed necessary.

Carp Facts​

Grass carp are fish imported from Asia for use in controlling aquatic vegetation. One of the few fish species which eat plants, grass carp may provide a low-cost, long-term, herbicide-free means of dealing with problem plants in your pond or lake. The designation of triploid signifies that they have been genetically altered at hatcheries to prevent the fish from spawning in Florida waters. A United States Fish and Wildlife Service inspection program helps certify the ploidy of the fish based on a procedure developed by Florida fisheries biologists  (Wattendorf, Robert J., 1986. Rapid Identification of Triploid Grass Carp with a Coulter Counter and Channelyzer. Progressive Fish-Culturist. 48(2):125-132)

 

The grass carp is actually one of the largest members of the minnow family. The back of the grass carp is silvery to dark grey, and the sides of the body are lighter with a slightly golden sheen. The belly is silvery white. Fins are generally greenish-grey. The fish has relatively large scales. The body shape is oblong with a round belly and broad head. Teeth have been replaced by specialized structures called pharyngeal teeth  located in the back of the throat. These are used for tearing and grinding plant matter.  They have an average "life span" of approximately 10 years.

 

Feeding Habits: As the name implies grass carp consume higher aquatic plants and submerged grasses (rooted macrophytes as opposed to algaes); they will also eat detritus, insects and other invertebrates when necessary. Because of their feeding behavior, they are used in this country under special restricted circumstances (see our permit page for details) to help manage aquatic plant problems. Triploid grass carp have three sets of chromosomes, instead of the normal two, which renders them functionally sterile. Triploids are produced artificially, by using hormones, stripping the eggs and mixing them with milt, then subjecting the fertilized egg to hydrostatic pressure, and finally suspending the fertilized eggs in well-aerated containers until they hatch. The resultant fish must be individually tested using a Coulter Counter, in a certification process developed by FWC biologists prior to being permitted for use. The FWC helps protect aquatic habitats by restricting the use of grass carp via permits to only these sterile fish and limiting the number allowed.

 

The largest triploid grass carp taken in Florida was 15 years old, 56" long and weighed 75 lbs. In China, grass carp are reputed to live up to 21 years and reach sizes of 5 feet and 100 pounds.