described Brandt's cormorants in the 

 vicinity of San Diego, California, as 

 occupying a variety of habitats, but 

 especially the large Macrocystis forest 

 off La Jolla. Cormorants feed by foot- 

 propelled pursuit diving but may also use 

 their wings underwater (Cowen pers. 

 comm.). The stomach contents of eight 

 Brandt's cormorants from San Diego kelp 

 forests revealed that they fed almost 

 exclusively on fishes that inhabit the 

 midwater among the fronds of Macrocystis 

 (Hubbs et al. 1970). These included the 

 senorita ( Oxyjul is cal ifornica ) , the 

 blacksmith ( Chromis punctipinnis ) , and the 

 kelp perch ( Brachyistius f ranatus ) (see 

 Section 4.5). The pelagic cormorant has 

 similar feeding habits (Ainley et al. 

 1981). Both cormorants are year-round 

 residents of California. 



Ainley and Sanger (1979) included 

 mysid shrimp as a major prey item of the 

 horned grebe ( Podiceps guritus ) , and the 

 eared grebe (_P. niaricul lis , Figure 23), 

 two species that winter along the 

 California coast. These small birds are 

 foot-propelled pursuit divers, and are 

 commonly observed within kelp forests 

 (Baldridge pers. comm.). It is probable 

 that they exploit the dense swarms of 

 mysids found within the midwaters of the 

 kelp community (see Section 4.2). 



Seaward fringe . The fringe areas of 

 kelp forests probably support the greatest 

 diversity of birds. The interface between 

 kelp and open waters often contains dense 

 aggregations of invertebrates and fishes, 

 perhaps because currents are reduced (see 

 Section 2.2). The brown pelican 

 ( Pelicanus occidental is cal ifornicus , 

 Figure 23) along with terns (Family 

 Laridae) are surface-plunging species that 

 may exploit concentrations of schooling 

 fishes along the canopy's edge. The loons 

 (Family Gaviidae), grebes (Family 

 Podicipedidae) , cormorants (Family 

 Phalacrocoracidae) , and scoters (Family 

 Anatidae) are all foot-propelled pursuit 

 divers that may opportunistically forage 

 along the edges of kelp forests. 



Pigeon guillemots ( Cepphus columba , 

 Figure 23) forage by wing-propelled 

 pursuit, diving nearshore during spring, 

 summer, and fall (Page et al. 1977). 

 Angel 1 and Balcomb (1982) reported that 



pigeon guillemots dive for prey along the 

 edges of kelp beds within the Puget Sound, 

 Washington area. Follett and Ainley 

 (1976) studied the diet of pigeon 

 guillemots on Southeast Farallon Island, 

 and found that they had fed upon 24 

 species of fish, the majority of which 

 were benthic. Common murres ( Uria aalge , 

 Figure 23) also forage via wing-propelled 

 pursuit diving, concentrating on open- 

 water fish species and squid (Croll pers. 

 comm.). They may also feed on the edges 

 of kelp forests. 



The majority of subsurface diving 

 seabirds do not occur in the kelp canopy, 

 but may be abundant at the canopy's 

 fringe. With increased kelp density, 

 subsurface diving may be restricted due to 

 the possibility of entanglement of feet or 

 wings (depending on the birds' mode of 

 underwater locomotion). 



4.6.1.3 Drift kelp . Plankton and 

 small fishes often concentrate around 

 drift kelp in pelagic waters. The red 

 phalarope ( Phalaropus ful icarius ) and the 

 northern phalarope ( Lob i pes lobatus ) are 

 found in California waters in summer and 

 fall, and often feed in association with 

 drift kelp far out to sea. Phalaropes are 

 believed to feed by seizing planktonic 

 organisms at the water's surface (Page et 

 al . 1977). Seabirds may also use pelagic 

 draft kelp as a roosting site (Keating 

 pers. comm.). 



4.6.1.4 Kelp wrack . Although some 

 drift seaweed is usually found covering 

 the intertidal zone in the vicinity of 

 rocky areas, the export of large amounts 

 of kelp to beach areas is a seasonal event 

 associated with intense wave action from 

 fall and winter storms. Beach drift can 

 support a microcosm of invertebrates (kelp 

 flies, fly maggots, beetles, various 

 crustaceans, etc.) that are, in turn, 

 available to birds as prey items (Yaninek 

 1980). A diversity of shore and 

 terrestrial birds forage upon algal wrack 

 on a seasonal basis (Davis and Baldridge 

 1980). Sanderlings ( Cal i dri s alba ) , black 

 turnstones ( Arenaria melanocephala ) , and 

 ruddy turnstones (A. interpres )," three 

 opportunistically feeding shorebirds, 

 regularly pick through kelp wrack. Common 

 crows ( Corvus brachyrhynchos ) , starlings 

 ( Sturnus vulgaris ) , and brewer's 



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