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Biological Approaches

There are a number of lake & pond management techniques available that can be considered biological or “natural” approaches. While many of these techniques meet with limited success, they can be worthwhile under certain circumstances and may help to improve the overall health of the pond even though they don’t solve specific issues in and of themselves. Aquatic Control has worked with many of these biological approaches and continues to identify appropriate uses for some of our clients as well as keeping abreast of new development and emerging technologies.

Enzymes and Bacteria

These “additive” products are designed to augment the pond’s existing natural chemistry and array of microorganisms. Enzymes and bacteria work in a number of ways. First they help to accelerate the natural process of decomposition. Secondly, the bacteria compete with algae for nutrients in the pond. Products such as these reportedly help reduce the muck layer and reduce the frequency and severity of nuisance algae blooms. They may also improve water clarity and quality. There are a wide array of specialized products that would fall under this category, but most are designed for small ponds and must be applied multiple times per season (often every two weeks or so). The testing and documentation of these types of products is limited at best and although the idea behind them is intriguing and worthy of more research and development, their success in solving specific issues may be limited. There are numerous products of this type currently on the market. Our biologists have reviewed many of these products and we have chosen a select few to incorporate into our management programs.

Herbaceous Fish & Insects

There are a number of organisms that are or have been investigated to provide control of nuisance plants and algae. The most common biological control measure is the triploid (sterile) grass carp. Grass carp are introduced into a lake or pond with the intent to consume nuisance aquatic vegetation, however they are non-selective and it’s often difficult to stock the right number of fish to achieve a balance of vegetated and open areas. The use of grass carp may be practical in situations where other management techniques, for whatever reason, are not available. The introduction of grass carp is illegal in all New England states except for CT. The may also be permitted for use in NY. State permits are always required and in most cases grass carp will only be allowed in private ponds or small lakes where the outflow can be blocked to prevent their escape.

Herbaceous insects have been used to control various invasive, aquatic plants, the most documented of which include the milfoil weevil (Euhrychiopsis lecontei) and the purple loosestrife beetle (Galerucella sp). Control projects using these insects have met with mixed success and research on these and other potential biological control are ongoing. Aquatic Control has been involved with a number of projects where these insects have been utilized.

Shoreline Management/Aquascaping

The overall condition and specifically the water quality of a lake or pond can be improved over time through proper shoreline management. On small ponds, aquascaping can improve aesthetic appeal while protecting the resource at the same time. Aquatic Control is familiar with various shoreline management and aquascaping techniques. We also have professional relationships with a number of respected landscape consultants and contractors in this field with whom we regularly work with on our client’s projects.

Biomanipulation & Plant Replacement

Manipulating the biological characteristics of a lake or pond is very project specific and should be considered only after careful study and planning. Some examples are adding zooplankton to increase grazing on algae, stocking or harvesting a particular species of fish to alter the food web or planting native plant species to increase biodiversity and reduce invasive plant growth. There have not been many successful projects of this type conducted, however such methods may be appropriate on well-understood lake/pond systems where resources are available to completed such complex endeavors. Aquatic Control has been involved in many such projects over the years and our staff would be happy to the possibilities with you.

Pond Dyes

Pond dyes are designed to alter the penetration of sunlight into a lake or pond, thus reducing the amount of photosynthesis that can be support plant and algae growth. In most case, dyes are not recommended for “natural” ponds and are more suitable for contained, man-made ponds with little or no outflow (storm water detention ponds, reflecting pond, golf course pond, etc). There are a variety of dye products, but the most common colors are blue and black. Usually the pond dyes breakdown over time and need to be re-applied periodically.

Fish & Wildlife Management

Although not specifically related to plant and algae control, enhancing the fish and wildlife habitat of a lake and pond can be a desirable goal. Whether it’s adding abiotic structure (i.e. logs or boulders) to provide shade for fish and basking sites for turtles or of stocking fish, Aquatic Control can help decide what’s best for your situation. Such measures can be used to enhance the overall health and ecology of your lake or pond.