The long winter is over and spring is here. Anglers will flood the parks, hoping to catch the big one. Hikers will explore the paths, and joggers will race past them. Children will throw rocks in the lake and chase the geese. And, inevitably, muskrats, algae, trash and tree overgrowth will begin to ruin your lake.
Now is the time for a bit of spring-cleaning. Hands-on lake cleanup is essential to the health of the fish, plants, insects and wildlife that depend upon its resources.
Hands-on Lake Cleanup
A well-maintained lake is a precious gift to the over 34 million American adults who spend an average of 16 days per year fishing, the 74 million who enjoy recreational boating and the uncounted millions who walk, hike and run on the paths and trails circling the water.
Paul Saldutte, Land Manager of Medina County Parks in Medina, Ohio, has 31 years of experience keeping lakes healthy for wildlife and people. He says step one is simply to “inspect each lake each spring and determine what kind of problems we might have.”
Common Problems - The Big Seven
1. Water control problems
2. Fish kill
3. Percentage of fishing ponds covered by weeds
4. Trees and shrub growth on top of dikes
5. Monofilament line and other trash
6. Algae overgrowth
7. Fish restocking needs
Common Solutions-The Big Seven
The goal, as in all maintenance plans, is to stay ahead of the curve. Here are ongoing maintenance tips that will help control/eliminate the seven big problems in lake management.
Clogged Lake Outlets
Leaves and other debris often clog lake outlets. The correct flow of water is essential to the health and welfare of a lake. In the Midwest, muskrats like to dig on or near dams or outlet flows. Controlling their population, usually by trapping, is often needed. Uncontrolled muskrat populations can lead to the collapse of dams and other costly repairs. Using "riprap" or submerged fencing is also a good way to avoid muskrat damage. Riprap is graded, angular rock. A correct mixture of aggregate size can aid riprap's ability to create an interlocking structure.
A heavy layer of snow or ice may cause depletion of oxygen, which in turn kills the fish. If you anticipate heavy fish kill, Saldutte recommends you scrape the snow and ice away and allow sunlight to penetrate into the water column. The sunlight keeps the plants alive, and they produce oxygen. Toxic runoffs from water or land may also kill fish and must be confirmed with lab tests and stopped at its source.
Aquatic Weed Control
As spring inches towards summer, Saldutte recommends you keep an eye on your aquatic weeds and, if necessary, perform weed control in late May or early June (northern climate).
“I highly recommend that you keep 15 to 20 percent of your fishing pond covered with some sort of weed,” says Saldutte. Weed cover can be floating weeds, submerged weeds (the bottom of the lake) or immerged weeds like cattails. Saldutte likes a balance between open water and weeds. He believes parks often try to keep lakes too clean. Weeds provide food and hiding places for fish and insects, and filter out contaminants like nitrates from fertilizers and other harmful chemicals that often find their way into the delicate ecosystem of the lake. They also help prevent erosion and add a majestic effect.
In Hubbard Valley and River Styx Parks in Medina County, Saldutte has introduced a natural biological control. An Asian fish brought to Ohio several years ago called White Amur is proving highly effective. “We use the kind that don’t breed and we don’t overstock. They allow me to use a biological control and not have to use chemicals.”
Saldutte went on to say that if the weeds become too sparse, the eel-like fish will “jump on the banks to get the grass.” However, there is always some kind of weed in the lakes. Before you do any kind of weed control, make sure the weeds are not endangered.
Dike Top Tree And Shrub Growth
At least once a year, Saldutte recommends that the banks be mowed. Trees that grow on top of dikes can slowly break the levy. Make a note of the potential damaging growth but wait until after nesting season (July or August) to mow because ducks, kill-deers, Canada geese, rabbits and other wildlife nest by lakes for easy access to water.
The thin, clear monofilament line anglers use is often left behind. Every year fish and wildlife may become wrapped in it and be hurt or even die from its strangle-like hold. Medina County is fortunate to have many volunteers who come in regularly to help clean up the fishing line or any other trash. They’ll take a canoe or rowboat and check the lake and its edges. A “stick pole,” a long stick with a nail on the end, is used to pick up visible trash on the bottom of the lake.
Using Copper Sulfate To Control Algae Growth
“Algae on top of the pond is our biggest problem,” states Saldutte.
Copper sulfate is added to counteract the invasive filament algae. Medina County uses 2.7 pounds per acre-foot of copper sulfate. This nation-wide formula is used in water above 60 degrees. However, Saldutte stresses, “Before you apply any chemical, do your homework.”
Make sure the weed is correctly identified, not endangered. Follow the chemical instructions exactly. Some chemicals are so strong the lake must be closed for a period of time. Read the labels and, if required by local regulatory agencies, make sure you are certified to apply the chemical.
Copper Sulfate--A Brief Primer
Copper sulfate is a contact herbicide and quickly kills sensitive algae species. However, copper can interfere with gill function and, if improperly used, can be toxic to fish. Most often, though, fish kills due to copper sulfate treatments are a result of massive algae kills and the subsequent loss of oxygen in the water.
The effectiveness and safety of copper sulfate is determined by alkalinity and water temperature. In water with an alkalinity less than 50 parts per million (ppm), the rate of copper sulfate needed to control algae can be toxic. Treatment at water alkalinity less than 20 ppm is extremely risky. In high alkalinity, above 250 ppm, copper sulfate quickly precipitates and is not effective for algae control. The toxicity of copper sulfate to fish increases as the water temperature increases, so you should avoid copper sulfate applications during hot summer months.
The drawbacks associated when using herbicides for aquatic vegetation control include:
1. Many break down or disappear in the pond/lake after a short period of time.
2. Re-treatment may be necessary to obtain desired results.
3. As with other methods, certain herbicides are suited to whole-lake treatment and others as spot treatments.
4. They can be expensive to use.
Spring is the time many anglers show up, ready to wet a hook, but it is not the time to determine what fish need to be re-stocked; that should have been done the previous summer and fall. One good way is to simply talk with fishermen at the end of the summer and ask them how the fishing is and what they're catching.
Simple surveys are another good way to get your hands around the data. A good survey can show what kind of fishing “pressure” or hours of fishing the lake is seeing. This allows you to place your order and stock your lake in the spring, which is always a good time to supplement bass, blue gill, channel cat fish or whatever the local favorites are.
It is springtime and the anglers are reorganizing their tackle box, boaters are oiling their hitches, and hikers are buying new boots. The animals are making nests, and the muskrats are eyeing the dike. Now is the time for the lake’s springtime maintenance. Follow this simple seven-step guide, then welcome all the new visitors with a beautiful, healthy lake.
Melanie Minch is a freelance writer in Medina, Ohio.