Ray Brown, Refuge Biologist
4/1/06

In the Spring 2005 edition of the Friends of Bombay Hook Newsletter, I introduced readers to the new multi-region, multi-refuge, multi-partner impoundment study that Bombay Hook NWR was embarking upon at that time.  Briefly, this large-scale research project is designed to provide refuges and wildlife management areas across the Mid-Atlantic, Midwest, and Northeast regions with information that will help us better manage these areas year-round to maximize their benefit for shorebirds, waterfowl, and wading birds.  Since Bombay Hook has become part of the research project, we have lost much of our management flexibility over two of our major impoundments until early in 2008.

You may recall that last year we managed Raymond Pool primarily as usual, with a gradual drawdown in spring to provide mudflats and shallow water for northward migrating shorebirds, followed by a primarily dry period in summer to allow the growth of moist soil vegetation (waterfowl food plants), followed by a gradual increase in the water depths through the fall and winter for migrating and wintering waterfowl.  The only difference last year was that we purposefully allowed the pool to go completely dry in mid summer instead of attempting to hold a small shallow pool in the center as in previous years.  The result was that we had excellent use by shorebirds in the spring, poor use by shorebirds in the late summer, reasonable growth of moist soil vegetation in the summer, and good use by waterfowl in the fall and winter.

Shearness Pool, however, was managed quite differently from usual last year.  Instead of gradually drawing down the water in spring to provide shorebird habitat, we kept the water high through the spring and summer, and gradually drew the water down in late summer to coincide with the southward migration of shorebirds from July through September.  We kept the water level low in Shearness longer than usual in the fall to give the moist soil vegetation more time to reach maturity and produce seed for migrating and wintering waterfowl.  Then we rapidly increased the water level in the pool in the fall for migrating and wintering waterfowl.  As a result of the management actions undertaken in Shearness last year, we had virtually no use by shorebirds in the spring but good use by shorebirds and wading birds in the late summer.  We had less moist soil vegetation produced overall, but especially in the south end of the pool in the study area that is delineated by the white poles extending from Daly Overlook.  Waterfowl use in the study area was moderate, but waterfowl use in the rest of Shearness was excellent because of the greater abundance of waterfowl food produced outside the study area.