Manmade Wetlands

Manmade wetlands generally lack the diversity of natural wetlands as they are designed and installed with a specific species or activity in mind. For example, ponds may be designed to hold water for irrigation, provide recreational opportunities or simple provide an esthetically pleasing backdrop to your home. No matter the primary intent for building a manmade wetland, they serve as wildlife habitat in the rapidly changing landscape of North Carolina. With a little effort, manmade wetlands can serve as home to a wider range of wildlife.   

Ponds

Whether referred to as a “fish pond”, farm pond” or just “the pond”, these wetlands seem to be the one that are most familiar. Ponds are one of those features on the landscape that attract us as humans. We may swim in a pond, fish in a pond, explore around a pond, kayak on a pond or picnic next to a pond. Each of these activities are a great way to have family fun or just enjoy a little time in the outdoors. But if we dig a little deeper, ponds are their own mini ecosystem including fish, plants, turtles, frogs, dragonflies, birds and many other living and non-living components. Considering the components of the ecosystem as you manage your pond and surrounding area will provide improved opportunities for fishing or simple wildlife observation. 

Constructing a pond

If you do not already have a pond and wish to construct one, you should seek professional guidance.  Many factors can impact the expense of construction and the long-term success of the pond.  Some soils will not hold water, allowing water to seep under or around the dam or water control structure.  Various water control structures are available and could be customized depending on your objectives.  Constructing a pond is a serious project which may impact natural wetlands, requiring permits for the Army Corp of Engineers.  Reach out to experts to assist with permitting, design, construction and management before you use heavy equipment.  Contact your County Cooperative Extension Office or local Soil and Water District for further instruction.

Management

In pond management, as with any other natural resources management, you need to define the management objective.  If you want to catch fish from your pond, what species?  Do you need to kill existing fish population to reach your objective, or can the existing species be managed to improve the health of the population?  For intensively managed ponds, it is recommended that a combination of the following species be considered when stocking:  largemouth bass , redear sunfish, hybrid sunfish, bluegill, and channel catfish.  Not all species listed must be included.  Usually it takes about 2 years for the fish to get established.  Be sure to harvest an adequate number of fish to maintain your goals.  It is much easier to keep up with maintenance harvests rather than starting over once the population gets out of control.  Fish samples will need to be taken to obtain information about population dynamics.  Taking water samples can determine if your pond will benefit from fertilizer or lime. 

Esthetic beauty is in the eye of the beholder. However, a pond that is too “clean” around the edge may limit biodiversity, thus limiting the efficiency of the ecosystem. Allowing native shrubs, sedges and rushes to grow along the edge of the pond (not on the dam) will provide structure for insects and amphibians to reproduce. Adult amphibians and insects, as well as their larva, are an important food source for many aquatic species. Submerged structure should be considered as well. Stumps, roots, rocks or trees provide cover for prey species and predators alike.Adding natural or manmade structures can help improve the productivity and enjoyment of your pond. 

Additional Resources

Waterfowl Impoundments

Waterfowl impoundments are specifically designed to hold water during fall and winter duck seasons then be drained during the summer months.  Generally, the water is contained with mounds of dirt called dikes or berms.  A water control structure or device is installed in the berm to allow the water level to be manipulated throughout the year.    

Establishment

When looking to build a waterfowl impoundment, there are a few questions that must be asked. Am I in a good flyway area? Do I have soil that will hold water? Do I have a natural water source, or will I need a pumping method?  What type of vegetation am I looking to manage? The best site to utilize is one with the correct type of soil and a water source that doesn’t require pumping. If you are interested in constructing an impoundment, check out the NC Partners Program to see if you are a good fit.

Management

Water control structures are slightly modified drainage pipes used not only to lower the water but also to raise it. Water control is key when managing waterfowl. By having control of the water level, you can draw levels down to plant “hot foods” such as corn, millet, or milo. Often a better alternative is to manage natural vegetation to enhance moist soil or submerged aquatic vegetation. Your water management plan will be centered around both your water control capabilities and the type of vegetation you want to manage. Be sure you are following the water quality regulations in your area. Consider improving habitat quality with the use of approved herbicides to control invasive species. Contact your local Wildlife Management District and Conservation Biologist.

Ephemeral or Vernal Pools

Small pools which hold water during the winter and spring can be very important for amphibians. These pools provide critical breeding habitat for a host of salamanders, toads and frogs. We can create these small wetlands where natural pools are lacking on the landscape. Focus on the surrounding habitat not just the pool itself. Make sure there is debris such as decaying logs, branches and rocks in the area to provide terrestrial cover for the amphibians. Likewise, the pool itself should have decaying leaf litter, coarse woody debris, living vegetation and rocks in it to provide cover and serve as a substrate for attaching egg masses.      

Small pool wetlands can be created by plugging ditches, installing water control structures or using plastic liners to hold water. 

Additional Resources

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