HABITAT 



Nesting The Common Goldeneye nests in holes, usually natural cavities 

 in trees, primarily in boreal forests, or in man-made nest boxes. More exotic 

 nesting sites include a ledge within a church tower (Bellrose 1976) and rabbit 

 ( Oryctolagus cuniculus ) burrows (Cramp et al . 1977). Open woods near the edges 

 of fields or marshes are preferred (Bellrose 1976). Palmer (1976b) also noted 

 nesting in floodplain forest, and on bog ponds and small lakes in forests. 



Feeding Common Goldeneyes in southwest Sweden preferred to feed on lakes 

 that apparently lacked fish; Eriksson (1979b) believed that this choice was the 

 result of competition between the ducks and the fish for food eaten by both. 

 During autumn on the Swedish west coast most Goldeneyes are found on subaquatic 

 meadows of Zostera marina , Ruppia spp., and Characeae (Pehrsson 1976). Golden- 

 eyes take most of their food from the bottom at depths of up to 4 m (13 ft), 

 with few probably diving deeper than 9 m (30 ft)(01ney and Mills 1963). Palmer 

 (1976b) reported that most food is obtained in 3-12 ft (0.9-3.7 m) of water; 

 maximum depths records for dives are about 20 ft (6 m) . Goldeneyes take food 

 from submerged surfaces or from the water, and frequently overturn and search 

 beneath stones (Olney and Mills 1963). 



Winter and Offshore Most Common Goldeneyes move to the coasts in winter 

 and frequent the open ocean or bays there. Some are found on fresh water in 

 the interior of the United States where large rivers and lakes remain unfrozen. 

 Palmer (1976b) indicated that non-breeding birds of this species are typically 

 found in shallow bays but raft at night well out from shore. Non-breeding birds 

 are also found in estuaries (preferably brackish) and near the mouths of rivers 

 (Palmer 1976b). Cramp et al. (1977) indicated that Common Goldeneyes are found 

 widely on both salt and fresh water in the western Palearctic but prefer estu- 

 aries and marine bays, sheltered shallow waters along the coast, and sewage out- 

 falls. These ducks are usually found in small flocks but may occur in aggrega- 

 tions of up to several hundred birds (Cramp et al. 1977). 



FOOD AND FEEDING BEHAVIOR 



Most Common Goldeneyes feed by day, obtaining their food by diving, appar- 

 ently to the bottom, except when pursuing fish. Bellrose (1976) timed 18 dives 

 by feeding Goldeneyes in the interior United States and found that they averag- 

 ed 30 sec in duration, with a range of 11-41 sec. Eriksson (1976) found that 

 ducklings fed by four methods: diving, surface feeding, dabbling, and pecking 

 at emergent vegetation. Diving occurred most frequently. Synchronous diving 

 by members of a feeding flock has been observed; in other instances, members of 

 a flock may dive one after another in rapid succession (Geroudet 1965 J^n Cramp 

 et al. 1977). 



Goldeneyes feed predominantly on animal matter but may feed to a consider- 

 able extent on plants in late spring and autumn; in addition, these ducks ex- 

 hibited marked local and seasonal variation in diet (Pehrsson 1976). Animal 

 foods made up three-quarters of the diet of a sample of 395 Common Goldeneyes 

 examined by Cottam (1939 _in Bellrose 1976); crustaceans, insects, molluscs, and 

 fish were the important groups represented. Among the plant food taken were 



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