University of Delaware
Office of Public Relations
The Messenger
Vol. 5, No. 2/1996
Champion of Delaware's coastal wetlands

     As a youngster, he hunted and fished in the wetland marshes
near his home on the outskirts of New Castle, Del. These days,
Dave Carter, Delaware '85, works with the Department of Natural
Resources and Environmental Control (DNREC) in Dover, Del., to
protect the marshes he loved as a child.
     After graduating from the University of Delaware with a
degree in biology, Carter intended to join the Peace Corps, but a
summer job with DNREC turned into a seven-year stint with the
Division of Fish & Wildlife, overseeing mosquito control
operations. While there, he tried to find alternative methods to
potentially harmful insecticides by introducing mosquito-eating
fish and insects.
     For the past three years as environmental manager for the
state's coastal management program, he has tried to protect
Delaware's fragile coastal areas. Currently, he's "doing some
highly technical work with specialized water quality sampling,
stormwater sampling and computer modeling" and can often be found
slogging through the marsh grasses, supervising his team of
engineers and biologists as they gather data about water birds
and water quality.
     Under Carter's jurisdiction are 30 to 40 wetland sites
encompassing some 10,000 acres along the Delaware and Christina
rivers, including the heronry on Pea Patch Island on the Delaware
River. Pea Patch Island is surrounded by waters containing large
amounts of industrial and municipal waste and is directly
affected by oil spills. Yet, it supports the largest East Coast
heronry north of Florida, attracting as many as 24,000 herons,
egrets and ibis each spring.
     How does this area maintain a healthy, stable population of
wading birds? "We really don't know for sure what factors make it
such a productive habitat for them," says Carter, "and without
knowing that, we're always at risk of losing them."
     Developing baseline data on this fragile area is part of
Carter's responsibility. "On Pea Patch Island, we're taking a
good look at the environmental and habitat needs of different
species. We're using the heron as one of the indicators of the
regional ecosystem," he explains, "because it's so dependent on a
much larger region." Another of his tasks is to use the data to
formulate policy that will keep not only the heronry but the
entire ecosystem healthy. With the heron's minimum survival
requirements in mind, land use can be planned so that areas
critical to the species' survival will be protected.
     Land-use policy, he says, is often shaped by political needs
and deep-rooted social values, which can be hard to change.
Dealing with differing opinions has been one of the challenges in
his work. It has entailed, for example, working one-on-one with
landowners around the town of Port Penn, listening to their
concerns and educating them about adjusting water levels. Such an
education process is critical, he says, since most remaining land
needing ecological management is privately owned.
     "If we're going to make true ecological strides, we've got
to be able to deal with people on their own private lands,"
explains Carter.
     But, Carter says his biggest stumbling block right now is a
shortage of scientific knowledge. "Most of the big problems have
been fixed," he says. "The problems we're looking at now are
harder to define. It's easy to identify a primary source of
pollution, but not so easy to find the secondary sources. We're
trying to get a better handle by doing some good monitoring, but
the science still needs to be developed in a lot of fields."
     Lack of knowledge also can be disastrous for highly
sensitive water bird populations. At the Thousand Acre Marsh
south of Delaware City, where water level is adjusted by tidal
gates, "what we think are relatively minor changes in water level
have a drastic impact on the water birds," says Carter. "If you
manipulate the water level, and it's too deep and they can't
catch fish in it as well, they have to go somewhere else."
     Sometimes, it's a choice of which species to protect. At the
Armstrong heronry south of Port Penn, the arrival two years ago
of a single nesting pair of bald eagles caused the entire heron
population to leave. "Should we protect the bald eagle, an
endangered species, at the expense of the entire heronry? It's an
environmental trade-off," he says.
     In wetlands management, there are no easy answers. The
invasion of the exotic grass phragmites in many marshes has
limited the growth of more diverse native vegetation better
suited to supporting wildlife. But, the common practice of using
herbicides to control the phragmites may harm the birds more than
it helps.
     "One of the concerns that has stuck with me," says Carter,
"is that we call it restoration and we spray phragmites and we
get different vegetation in. We definitely make changes to the
marsh. But, is it necessarily good and for the best? When I look
at it from a regional perspective, I don't know."
     Weighing the conflicting interests of wading birds, shore
birds, waterfowl-and people-is one of the challenges of Carter's
job.
     Although current knowledge of how to best manage wetland
areas may be incomplete, Carter's philosophy is to proceed with
what we know now. "We really have to continue with good faith on
the current track to restore the wetlands and be prepared to
change our direction as we get better data," he says. "Mistakes
may be made, but the alternative is to do nothing. If we find
down the road that what we're doing isn't working, we can correct
our mistakes then."
     Ultimately, he says, he'd like to leave the areas he's
worked on in better shape for the next generation.
                                             -Valerie Baddorf