A marina worker at Geist Reservoir hooked a Chinese mystery snail, an exotic species already prominent in the reservoir, while fishing recently, and on it was another undesirable species: An adult zebra mussel.

The find could signal trouble for Geist, much as the zebra mussel’s presence has affected other waters.

 “That’s one invasive species colonizing on another,” said Doug Keller, aquatic invasive species coordinator with the Indiana Department of Natural Resources Division of Fish and Wildlife (DFW).

Previously found in more than 65 bodies of water in 44 counties throughout the state, the discovery marks the first time the mussel has been found in the Indianapolis area. Zebra mussels were also discovered last year in Summit Lake, the first population known to occur in Henry County.

Keller said the effect of zebra mussels can be devastating where the invasive species successfully colonizes.

“Zebra mussels can rapidly multiply and are known for clogging drainage and filtration pipes,” he said. “Besides pipes, they can attach to virtually anything in the water column, including rocks, limbs, piers or even boats.”

Geist is one of three water supply reservoirs for the Indianapolis area. Keller said as zebra mussel numbers increase in Geist and downstream in Fall Creek, there could be negative impacts to the water utility’s withdrawal capacity.

Zebra mussels are originally from Europe and spread rapidly across North America in the 1990s. Aside from being a costly nuisance to humans, zebra mussels may also cause declines in fish populations. By filtering tiny plants, called phytoplankton, out of the water column, zebra mussels diminish the base of the food chain, potentially causing declines in all other aquatic life, including fish.

Keller said few options for eradicating the mussel exist, short of eliminating every other living thing in the reservoir. The best means of control, he said, is by educating boaters about preventing further spread of the mussel.

Typically, zebra mussels are transported by human recreational activities such as boating or fishing. A few simple steps can prevent the spread of zebra mussels and other invasive species.

Removing all aquatic vegetation and draining livewells, bilge, water lines and boat trailers at access ramps will prevent transport of the mollusk to other waters. Drying equipment after each use also is important.

“Letting all equipment dry for five days after a boating trip will prevent the spread of both adults and larvae,” Keller said. “However, if you plan to visit a body of water sooner, you can use a solution of 5 percent bleach and water to clean and disinfect all of your equipment.”

Record muskie egg harvest at Lake Webster

To meet the production goals of Indiana’s statewide muskellunge stocking program, DFW biologists collected nearly 1.5 million eggs this spring from adult female muskies at Webster Lake.

The eggs were taken from 35 female muskies and fertilized with milt from male muskies, both of which were captured in large trap nets set at six locations between March 30-April 6 in the 774-acre Kosciusko County lake. During the eight-day period, biologists netted 128 muskies, including 74 males and 19 additional immature or “spent” females that had already released their eggs.
“We set a record this year for the fewest number of days needed for egg-taking,” said Dave Clary, manager of the Fawn River State Fish Hatchery in Orland. “It usually takes 10 to 15 days. The weather probably had a lot to do with our quick success this spring.”
According to Clary, weather changes and variable water temperatures can cause fluctuations and delays in muskie egg development.

Of the nearly 1.5 million eggs obtained this year, more than half (44) were taken on April 3. The largest female muskie captured was 46.5 inches long.

Biologists extracted and fertilized more than 600,000 eggs, which also broke the record for a single day egg-take. Once the muskie eggs were fertilized, Clary transported them to the Fawn River Hatchery, where they were placed in hatching jars.

Just before hatching, the eggs were shipped to East Fork State Fish Hatchery in southwestern Indiana, where the newly hatched muskie fry will be fed tiny pellets similar to food for aquarium fish.

“The young muskies will be raised throughout the summer at East Fork Hatchery, fed live minnows for 30 days in the fall and then stocked in various public lakes throughout the state,” Clary said. “They are normally 8 to 10 inches long by the time they are stocked.”

The views and opinions expressed in this column are those of the author and not necessarily those of Farm World. Readers with questions or comments for Jack Spaulding may contact him by e-mail at jackspaulding@hughes.net or by writing to him in care of this publication.