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Beaver
Pond Management
Beavers are
distributed statewide and inhabit a variety of wetlands. Today,
beaver populations are on a steady increase. Trapping and
available food sources are the major factors which limit beaver
populations.
Beaver ponds
provide a diversity of habitat types depending upon the size,
age, and hydrology of the area. The ponds effect wetland quality
by filtering sediment and organic matter that is normally
carried down stream. The transport of organic matter provides a
nutrient base for invertebrates and aquatic plants. Aquatic
invertebrates are the protein base for breeding waterfowl and
their broods.
Beaver ponds
may be managed for waterfowl, but water level control structures
need to be established. Three successful designs that have been
used are the three log drain, box drain, and perforated plastic
pipe. Water levels in early spring must be sufficient to attract
breeding pairs and then maintained for brood rearing. However,
prolonged stable water levels over several years becomes
detrimental because plant diversity is lost.
Ponds should
be drained after July 1st of each year. Earlier draining may
expose young birds to predation. A partial draw down of 1-2 feet
is recommended to promote germination of seed-producing emergent
plants. The shallow areas may dry out well enough to disc and
plant Japanese millet, or seed Japanese millet directly onto the
moist mudflats.
In areas
where elevations are not suitable for drainage, ponds may be
enhanced by introducing duckweed and watermeal. If the overstory
is too dense and shades out the growth of aquatic plants,
clear-cutting small openings will be beneficial.
Where beaver
populations are left unchecked they eventually deplete their
food supply and move from the area. The beaver meadow which
remains has lost plant diversity and available surface water.
The site becomes useless to waterfowl and other wetland wildlife
species and takes years to recover from these changes. To
prevent and/or to reduce beaver damage, the population must be
kept within the area's carrying capacity. As a general rule
25-30% of the fall beaver population should be removed through
trapping. Live trapping and translocating beaver is discouraged
to prevent the spread of disease and because most suitable
habitats are already populated with beaver.
For water
control plans and designs contact:
Virginia
Department of Game and Inland Fisheries
5806 Mooretown Road
Williamsburg, Virginia 23188 |