Waterfowl utilization of two coastal marshes at Cape Jourmain, New Brunswick

In 1966, during initial construction of the since aborted Prince Edward Island ~ New Brunswick Causeway, a portion of the salt marshes at Cape Jourimain, Ne Be, was impounded. Waterfowl utilization of this newly created brackish marsh and the adjacent tidal salt marsh was investigated from spring to fall, 1972 and 1973. Vegetation, aquatic invertebrates and water quality were described to provide basic habitat information. Black ducks Anas rubripes Brewster, American green— winged Anas crecca carolinensis (A.0.U. 1973) and blue-—winged teal Anas discors Le were the most numerous species. Generally, fledged waterfowl were present in greater densities on the impounded marshes while the proportion of ducks feeding was higher on the salt marshes. [In fall, waterfowl on the impoundments foraged little during the day. In the evening they moved to the tidal habitat and returned to the brackish areas during the early morning. The same diel movement pattern was exhibited by ducks from a nearby fresh water pond. Brood density was five times greater on the impoundments in both years. The species diversity of duck broods was also greater on the brackish habitat. I propose that the distribution of waterfowl is influenced by a number of interacting factors of varying importance and suggest some of these.