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WATERFOWL BREEDING GROUND SURVEY IN MARYLAND AND VIRGINIA 
William R. Nicholson 
Introduction 
The waterfowl survey during 1952 was confined to the brood season. No 
breeding ground or nesting studies were made. It represents the first attempt - 
insofar as is known - to quantitatively measure the production of waterfowl] in 
Maryland and obtain yearly index figures that will be comparable, 
The aerial transect method of sampling was used almost exclusively. Flights 
were made over all areas that were thought to contain sizable breeding populations. 
The aerial work was greatly facilitated by a cooperative arrangement between 
Delaware, Maryland, and Virginia. E. B. Chamberlain of the Delaware Game and 
Fish Commission was contracted to fly the transects:'in Maryland and Virginia and 
was released from his duties in Delaware during the time the work was done, The 
writer acted as observer on all flights over the parts of Maryland and Virginia that 
are located on the Delmarva Peninsula. C. P. Gilchrist of the Virginia Commission 
of Game and Inland Fisheries acted as observer on flights over the mainland sections 
of Virginia and Maryland. Results of the Virginia flights are incorporated in this 
report. 
Methods Used in Sampling and Areas Covered 
Bordering the Chesapeake Bay and Atlantic Coast are extensive marshes that 
are important as nesting areas for several species of waterfowl. The most extensive 
areas are located on the Delmarva Peninsula, bordering the Chesapeake Bay and 
adjacent rivers. They range from the fresh water aquatic type to the brackish marsh 
vegetated with three-square (Scirpus spp.), saltmarsh grasses (Spartina patens and 
S. alterniflora), and needle-rush (Juncus roemerianus). The brackish marshes are 
most widespread and many have numerous ponds and tidal guts interspersed with 
small areas of high ground that provide good nesting and rearing habitat. 
Similar marshes occur on the western shore of the Bay. However, they are 
generally small and much less extensive than those on the eastern side. Several 
large rivers providing an aquatic habitat are a major feature of this region. 
On the Atlantic Coast side of the Delmarva Peninsula the marshes are highly 
saline and covered almost entirely with Spartina patens and 5S, alterniflora. The 
most important nesting species is the black duck. Blue -winged teal and wood ducks 
nest locally; in recent years gadwalls have been reported. 
For the purpose of estimating waterfowl production by aerial censusing, a 
stratified sampling system has been developed and several habitat classifications 
adopted by the Fish and Wildlife Service and cooperating States. In Maryland and 
Virginia only two - or possibly three - types of habitat contain breeding populations 
that can be measured by aerial transects. The ditched coastal and unditched 
estuarine marshes are the most important. It has not yet been decided whether 
portions of the Atlantic slope type have breeding populations large enough to sample. 
