WERTHEIM NATIONAL
WILDLIFE REFUGE (LONG ISLAND, NEW YORK) WATER MANAGEMENT DEMONSTRATION PROJECT:
THE FIRST FIVE YEARS
David J. Tonjes
Department of Technology and Society
Stony Brook University
Dominick Ninivaggi
Division of Vector Control
Suffolk County (NY) Department of Public Works
ABSTRACT
As part of the Suffolk County (NY) Vector Control and
Wetlands Management Long-Term Plan, a demonstration project for aspects of marsh
management was conduct across four parcels (~160 acres) of the Wertheim
National Wildlife Refuge (Shirley, NY).
Two of the areas were altered (Area 1, in early 2005) and Area 2 (in
early 2006), while the other two areas served as controls for the treatments. Monitoring began in late summer, 2003, so by
2007 there were two seasons pre-treatment data for
Area 1 and three seasons for Area 2, and three seasons of post-treatment data
for Area 1 and two seasons for Area 2.
Treatments were to fill ditches, install ponds, and re-engineer or
create tidal channels.
We will present monitoring data from the first five
years of this project. The data show
that the primary goals of the project (to decrease the need for pesticide
applications, improve habitat diversity, reduce the expansion of Phragmites,
and increase fish and bird use of the marsh) are being achieved, and the
measurements of differences were generally found to be statistically
significant. Not all pre-project
expectations were met, however. Invertebrates
declined in abundance, the vigor and extent of Spartina patens was
significantly reduced in Area 2, and some declines in marsh productivity were
also measured in Area 2. One of the
treatment areas appears to have become drier, and the other appears to have
become wetter, although a clear explanation for the divergent results has not
been found. Finally, although similar
kinds of projects in other jurisdictions have eliminated all need for larval
mosquito control, larvicide applications to reduce mosquito numbers, although
greatly reduced in number, have been continued post-treatment here.