3. Wading birds. Birds that obtain their food by wading and stalking their 

 prey in shallow water. They are relatively long legged, long necked, and 

 light bodied and include herons, egrets, and ibises (table 14-3). 



4. Waterfowl. Birds that obtain their food either by diving or dabbling, 

 breed in fresh water, and winter at sea, in estuaries, or open fresh 

 water. This group, which includes ducks, geese, and swans, is discussed 

 in chapter 15. The three waterfowl species discussed with the seabirds in 

 this chapter are grebes, loons, and eider ducks. 



Within these groups, birds are further divided according to their seasonal 

 occurrence in Maine as follows: 



1. Permanent residents. Species present during all seasons. The term 

 "permanent resident" refers to the species rather than to individual 

 birds. Birds that breed in Maine may not necessarily be the same 

 individuals that winter in Maine (e.g., great black-backed gull, herring 

 gull, common loon, and common eider). 



2. Breeding summer residents. Species breeding in Maine that are present only 



during the breeding season and during migration. 



3. Nonbreeding summer residents. Species that breed in the southern 

 hemisphere and spend the winter season in northern waters (Wilson's storm 

 petrel and the shearwaters), and non-breeding individuals of species 

 breeding farther north (subadult and nonbreeding adult gannets , 

 kittiwakes, fulmars, murres , and great cormorants) or to the south 

 (certain herons). Most species in this category are seabirds. 



4. Migratory residents. Species present only during the fall or spring 

 migration. 



5. Winter residents. Migratory species that winter locally but breed 

 elsewhere (several seabirds and purple sandpipers). 



SEABIRDS 



Seabirds spend most of their lives far at sea or in the waters along the 

 immediate coast. In Maine, seabirds are represented by loons, grebes, 

 shearwaters, storm petrels, gannets, cormorants, eiders, gulls, terns, 

 jaegers, and alcids. In the characterization area 39 species of seabirds 

 occur regularly (table 14-1) and 18 species are rare visitants (table 14-4). 

 Fourteen species breed in coastal Maine (table 14-1). 



Seabirds feed primarly in open water habitats and, to a much lesser extent, in 

 intertidal areas. They are high level consumers, taking a variety of animal 

 prey ranging from zooplankton and shrimp to finfish, and may influence the 

 structure of their prey communities. Seabirds may form feeding groups with 

 members of their own species and with other species of seabirds, and sometimes 

 with marine mammals, finfish, bald eagles, and ospreys. Occasionally seabirds 

 are prey for large falcons, bald eagles (mostly in winter), large finfish, 

 marine mammals, and, of course, hunters. 



14-3 



10-80 



