Where laughing gulls nest abundantly (Virginia, Maryland, and New Jer- 

 sey), their mean colony size is very uniform. Without data on available 

 nesting habitat, marsh production, and feeding ecology of gulls in the two 

 areas, any suggestion of causal factors influencing colony sizes would be mere 

 speculation. 



HABITAT UTILIZATION 



Nesting habitats are categorized into two major types, mainland or is- 

 land. Islands are further classified as barrier, marsh, or "coastal" (all 

 those exclusive of the two former types); mainland habitats include contiguous 

 marshes, beaches, or woodlands. Nesting commonly occurred on dredge deposi- 

 tion material at either marsh, barrier island, or mainland sites. Construction 

 landfill was also used for nesting. In a few cases, artificial sites such as 

 piers, buoys, and barges provided nesting substrate. 



The proportion of nesting seabirds and wading birds in each habitat type, 

 by State, is shown in Table 17. The among-State differences observed resulted 

 from two major factors: coastal physiography and development. The coastal 

 shores in New England are predominantly steep and uneven with large numbers of 

 rocky islands. In contrast, extensive embayments and marshes bounded by long 

 barrier islands characterize the coast from Long Island, New York to Virginia 

 (Clark 1974). Because of this major physiographic difference only a small 

 percentage of colonial waterbirds in New England nest on barrier islands or in 

 marshes. The majority of colonial birds from Cape Cod, Massachusetts north 

 nest on small, rocky islands. 



Urbanization and recreational activity along the coast appears to have a 

 marked influence on colony distribution. A comparison of the five States (New 

 York to Virginia) with similar coastal topography reveals major nesting pat- 

 tern differences which parallel human activity levels. In Virginia, along the 

 Eastern Shore, about 80% of the barrier island coastline is owned by the 

 Nature Conservancy, a private conservation organization dedicated to protect- 

 ing the natural environment (R. Hennessey pers. comm. ). In contrast, fewer 

 sections of outer coast are protected either from public or private recreation 

 access in New York, New Jersey, Delaware, and Maryland. However, a rank 

 correlation analysis of barrier island use by seabirds (Table 17) and bathing 

 beach access (Table 18) did not yield a significant relationship (Spearman r 

 = 0.22, P > 0.05). Although barrier island use by nesting seabirds is mucn 

 higher (as expected) in Virginia where the ocean front is protected (Table 

 17), Long Island, New York ranks second in seabird use despite the fact that 

 major stretches of beach are not protected. However, long-established colony 

 sites of terns and skimmers are protected by signs on the south shore beaches 

 of Long Island. Also, herring gulls have habituated to automobile traffic to 

 such an extent that one of the largest colonies in the State occupies several 

 loops of a parkway along Jones Beach. 



Wading birds use nesting habitat more similarly in the different States 

 than do seabirds (Table 17). Even in New Jersey and New York, significant 

 numbers (37% and 26%, respectively) nest on barrier islands. Perhaps because 

 they nest in dense, inaccessible shrubs or trees away from bathing beaches, 

 they are much less vulnerable to human intrusion than are seabirds which nest 



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