MARYLAND (ATLANTIC COAST/CHESAPEAKE BAY) 



Because of the interposition of a large land mass (the Delmarva penin- 

 sula) between the Chesapeake Bay and the Atlantic coast of the State, nesting 

 populations of waterbirds for each region are treated separately in this 

 report (Tables 35 and 36). 



Seabirds 



Great black-backed and herring gull populations have increased much more 

 rapidly at Smith Island in the Chesapeake Bay than they have along the 

 Atlantic coast (MOS, MB, M. Byrd unpubl. notes). In 1977, herring gull num- 

 bers had increased at six coastal sites. Laughing gulls nest primarily at one 

 coastal colony, but none nest on the Bay. 



Forster's terns, primarily coastal marsh nesters, are probably as abun- 

 dant today as ever. A reduction along the coast in 1977 was offset by an 

 increase at four Chesapeake Bay colonies. Gull-billed terns have nearly 

 disappeared in the past 25 years in the State. They were not recorded as a 

 breeding species in 1976 or 1977. The previous peak was only about 35 pairs 

 in 1951 (AFN, MOS). 



Common terns are equally abundant on both Atlantic and Chesapeake Bay 

 coasts. Populations have been quite stable along the coast (MOS, Stewart and 

 Robbins 1958) and may be increasing along the Bay although earlier reports 

 were incomplete (MB). Virtually all of the coastal beaches are disturbed 

 heavily by humans which apparently forces the terns to nest on small marsh 

 islands. 



Roseate terns nested on Assateague Island in 1933 (Stewart and Robbins 

 1958) but, with one exception, have not nested since. The royal tern is at 

 its northern range limit in Maryland and numbers have fluctuated quite widely 

 since the early 1950's (Stewart and Robbins 1958, Bridge and Weske 1961, MOS). 

 The birds apparently shift between one or two sites in Maryland and the larger 

 Virginia colonies nearby (J. Weske pers. comim.). A few sandwich terns recently 

 have nested (J. Weske pers. comm.) in royal tern colonies but are also at 

 their northern range limit in Maryland. The black skimmer appears to have 

 declined since the 1950's. Only about half as many nests were found in 1976 

 and 1977 (M. Byrd pers. comm.) as in 1951 (Stewart and Robbins 1958). 



Least terns have declined sharply along the coast. Stewart and Robbins 

 (1958) reported that 285 pairs bred north of Ocean City in 1948. None were 

 found in 1977 (M. Byrd pers. comm.). In the Chesapeake Bay, total numbers 

 have remained fairly stable but the number of colonies has declined from miore 

 than 20 in the late 1940' s and early 1950's to only 2 in 1977. They persist 

 in some urbanized areas (New Jersey, Long Island) because of their propensity 

 for nesting on newly-created sites such as landfills. In Maryland perhaps no 

 alternative sites are available. 



Wading birds 



After a rapid expansion during the early 1970's (MB, MOS), the glossy 

 ibis population recently has' declined along both Chesapeake and Atlantic 

 coasts (M. Byrd unpubl. notes) Great blue herons are thriving at 13 Bay colo- 

 nies with an increase in the past 10-12 years. The harsh v/inter of 1976-1977 

 may have accounted for the 197 7 decline (C. Robbins pers. comm.). 



75 



