Drought could boost fish size at Mozingo lake

Though it sounds hard to believe, this summer's ongoing drought could be a good thing for anglers.

With the combination of little-to-no precipitation and extreme heat, lakes and ponds are shrinking daily.

The upside is that in ponds that are deep enough to allow fish to survive, the big ones are likely to get even bigger, says Scott Ryan, northwest Missouri fisheries regional supervisor for the Missouri Department of Conservation.

When water levels drop below vegetation lines, prey fish such as bluegill are forced into deeper water with predators like largemouth bass.

Ponds that are under-fished typically have smaller fish due to stunted growth, but as prey becomes more vulnerable without the cover of vegetation, predators will have more chances for a meal.

"This allows the stunted largemouth bass the opportunity to grow significantly with the newly available food source," Ryan said. "And by thinning the number of bluegill, the surviving bluegill have more food so they too will tend to grow to a larger size."

Mozingo Lake easily falls into the category of lakes and ponds that should see an increase in fish size, along with many larger ponds in the area.

In a lake with a maximum depth of 40 feet, Mozingo's fish population has plenty of room in the 1,000-acre impoundment.

Park Supervisor Grant Evans said that as of August 16, the water level of the lake is down 30 inches from where it typically is this time of year.

"It will be interesting to see how that drop will effect the lake in the years to come," Evans said. "We don't know if it will help or hurt, but we are keeping an eye on it."

Falling water levels are also exposing more vegetation around the shorelines of area lakes and ponds.

"One of the biggest problems landowners report with their ponds is excessive vegetation," Ryan said. "If water levels stay low over the winter, a significant portion of emergent vegetation will be exposed to winter freezes and will not survive into next year. Droughts can improve the overall conditions in many ponds."

Several large fish kills have been reported throughout the state, a kill at Lake Contrary in St. Joseph in the first week of August resulted in the death of an estimated 20,000 fish, mostly Asian carp.

Shallow water and hot temperatures cause low oxygen levels, therefore killing fish. Ryan said small fish kills can actually boost aquatic populations in the long run. Weaker fish are thinned out, and the survivors grow larger in a less competitive environment.

To combat the effects of the drought and record-breaking heat, MDC officials suggest that landowners deepen shallow ponds.

Ponds with a depth of eight feet or more over at least 25 percent of their surface area give fish a far better chance of surviving high temperatures.

An MDC study at Mozingo earlier this year found that the number of trophy-sized fish is increasingly annually. The drought could boost the lunker population even higher

In addition, lake staff and conservation personnel have been planting water willow at the lake in an attempt to slow erosion and eradicate invasive Eurasian watermilfoil.

"Low levels shouldn't hurt it [water willow] at all," Evans said. "Unless it gets really dry, much worse than it is now."

Evans said he has seen these situations before, and that the water willow should be hardy enough to survive if drought conditions persist.

He added that low water is giving his team a chance to place more brush in trouble spots where erosion is the worst.