How To
Vernal Pond Encore
by Thomas Biebighauser, USDA Forest Service
Editor: A review of Mr. Biebighauser’s A Guide to Creating
Vernal Ponds is found in The Bookshop department on page 36.
Vernal ponds are ephemeral wetlands that fill with water in the spring
and dry out in the fall and are often isolated from other bodies of water.
Perhaps one of their most significant characteristics, however, is that
they are void of fish, thereby providing safe havens for many amphibian,
insect, and crustacean species.
It has been learned through interviews and by examining the evidence
(drainage ditches and tiles) that vernal ponds were once common in Kentucky.
Most have disappeared. Recognizing the ecological value of this habitat
type, a partnership formed to reestablish the ponds on public lands. During
the past 4 years, the partners have constructed more than 300 vernal ponds,
ranging in size from 0.1 to 3 acres, on the mountain ridges and in the
river valleys of the Daniel Boone National Forest in eastern Kentucky.
A variety of techniques was used to build the ponds. Small bulldozers
shaped the new wetlands where clay or silt-loam textured soil was present.
Synthetic fish-grade liners were used where soils were course-grained
and porous. Track-hoes and explosives were used on sites having an elevated
water table.
The ponds were located in both sunlit and shaded areas. Wetlands established
in full sunlight have been found to grow more than 50 species of aquatic
plants within 5 years. Care was taken during construction to make sure
that the sunlit ponds could dry out each year—an important factor
for keeping cattails from crowding out more desirable plants.
These new wetlands provide habitat for an abundance of wildlife. Hundreds
of nights of mist-netting have found 10 bat species, including the federally
endangered Indiana and Virginia big-eared bats. Interestingly, in the
summer months, the preponderance of bats captured were pregnant or lactating
females.
Partners built the ponds to resemble the few remaining in the area. They
were constructed to retain water long enough for amphibian larvae to develop,
yet not so long that larvae-feeding fish could become established. Wood
and gray tree frogs, American and Fowler’s toads, and spotted Jefferson’s
and four-toed salamanders are just some of the amphibians using the ponds
as breeding habitat.
Wood ducks likewise have made extensive use of ponds constructed in the
shade beneath canopies of oaks, partaking of fallen acorns and macroinvertebrates—the
food needed to sustain energy for migration. Leaves falling into shaded
ponds have provided a rich environment for invertebrates important to
amphibians’ diets.
The vernal ponds also are the focus of an enterprising USDA Forest Service
environmental education program. Every year, Forest Service staff lead
more than 400 students on field trips into wetlands. Students don waders
and are handed nets, field scopes, clipboards, and data sheets to actively
sample the wetlands’ wildlife. Before returning home, they have
learned how to identify a vernal pond, whether in its wet or dry state.
Students also take with them a better understanding of the wetlands’
value to wildlife and people.
Bringing back Kentucky’s vernal ponds is improving life for creatures
of the forest—it is also helping to positively shape our youth’s
perspective on the environment.
For more information, contact Tom Biebighauser, Wildlife Biologist,
USDA Forest Service, 2375 Kentucky Highway 801 South, Morehead, Kentucky
40351, (606) 784-6428, tombiebighauser@fs.fed.us.
Vernal Pond Construction Partners
American Electric Power Company
Ducks Unlimited, Inc.
East Kentucky Power Cooperative, Inc.
U.S. Environmental Protection Agency
Kentucky Department of Fish and Wildlife Resources
Kentucky PRIDE
National Fish and Wildlife Foundation
National Wild Turkey Federation
National Wildlife Federation
Rowan County Wildlife Club
Steele Reese Foundation
USDA Forest Service
Wal-Mart Foundation
Waterflow Systems, Inc. |
