13 



to decline (Carry and Redner 1970; Redner 

 and Payne 1971; D. R. Young et al., unpub- 

 lished manuscript); residues in fish and in the 

 brown pelicans also began to decline (Ander- 

 son etal. 1975). 



In 1964, sandwich terns and spoonbills 

 (Platalea leucorodia) were found dying on the 

 island of Texel in the Dutch Wadden Sea. The 

 birds were in tremors and convulsions, signs 

 comparable to those found in other birds 

 poisoned by organochlorine insecticides (Koe- 

 man and van Genderen 1965, 1966). Studies of 

 the distribution of chlorinated hydrocarbons 

 in birds, fish, and mussels (Mytilus edulis) 

 from localities along the Dutch and West 

 German coasts and in the eggs of seabirds of 

 Great Britain indicated a point source of con- 

 tamination by dieldrin, endrin, and telodrin. 

 Telodrin, an insecticide not used in Europe at 

 that time, was being manufactured with diel- 

 drin and endrin in a factory near the mouth of 

 the Rhine River. When it was discovered that 

 these residues were coming from the insecti- 

 cide plant, measures were taken to eliminate 

 discharge; residue levels in the local seabirds 

 began to decline and the sharp decrease in 

 population numbers was halted (Koeman et 

 al. 1968). 



In addition to these two incidences, coastal 

 contamination from local but diffuse sources 

 has resulted in high levels of organochlorines 

 in birds in Japan, North America, and 

 Europe. Levels of PCB in Japanese birds, in- 

 cluding several species of gulls, were compa- 

 rable to those in industrial areas of North 

 America and Europe (Fujiwara 1974). The 

 PCB residues in breast muscle of eight little 

 egrets (Egretta garzetta) that were found 

 dead or dying in Tokyo Bay ranged from 

 0.3 to 180 ppm (22-1,600 ppm, lipid basis) 

 with a geometric mean of 9 ppm. Residues of 

 PCB in the breast muscle of eight black-tailed 

 gulls (Larus crassirostris) ranged from 

 3-39 ppm, with a geometric mean of 13 ppm 

 (Doguchi 1973). 



In western North America comparatively 

 high levels of DDT and PCB contamination 

 were found in common murres (Gress et al. 

 1971) and the ashy storm petrels (Oceano- 

 droma homochroa) (Coulter and Risebrough 

 1973) breeding on the Farallon Islands and in 

 great egrets (Casmerodius albus) and great 

 blue herons breeding at a coastal site (Faber 

 et al. 1972) near local sources of pollution. 



Most eggs of marine birds from the Strait of 

 Georgia contained more PCB's and DDE and 

 had a higher PCBrDDE ratio than did eggs 

 from the west coast of Vancouver Island and 

 from the Queen Charlotte Islands (Table 2). 

 This comparison within a relatively small re- 

 gion (i.e., the Pacific Coast of British Colum- 

 bia) further illustrates the principle that eggs 

 from birds nesting farther at sea are likely to 

 contain lower levels of organochlorines than 

 those nesting nearer the mainland. Average 

 PCB levels in these samples almost always ex- 

 ceeded those of DDE. 



Fish, crabs, and shellfish were collected 

 from the lower Fraser River, its estuary, and 

 selected areas of Georgia Strait (Albright et 

 al. 1975). Generally, PCB's were present at 

 higher levels than DDE, and greatest concen- 

 trations of these compounds occurred in biota 

 from waters adjacent to the city of Van- 

 couver. With one exception, animals from 

 Georgia Strait and those away from the im- 

 mediate influence of Fraser River water con- 

 tained no detectable levels of chlorinated 

 hydrocarbons. 



High levels of DDE and PCB in double- 

 crested cormorants from the Bay of Fundy 

 (Zitko and Choi 1972; Zitko et al. 1972) most 

 likely have resulted from past DDT use in 

 New Brunswick and from diffuse sources of 

 PCB's along the eastern North American 

 coastline. Similarly, contamination levels in 

 ospreys (Wiemeyer et al. 1975; Spitzer et al. 

 1977) in coastal Connecticut, Massachusetts, 

 New York, and New Jersey most likely were 

 derived from local sources of contamination. 



Bald eagles found sick or dead in the United 

 States during 1966-72 were analyzed for or- 

 ganochlorines (Mulhern et al. 1970; Belisle et 

 al. 1972; Cromartie et al. 1975); DDE, ODD, 

 dieldrin, and PCB's were detected in most of 

 the 145 eagle carcasses. Eighteen of the 

 eagles contained possibly lethal levels 

 (greater than 4 ppm) of dieldrin. Since 1964 

 when data were first collected, 8 of the 17 

 eagles obtained from Maryland, Virginia, 

 South Carolina, and Florida possibly died 

 from dieldrin poisoning. All four specimens 

 from Maryland and Virginia were from the 

 Chesapeake Bay Tidewater area. 



In December 1973, eight ruddy ducks 

 (Oxyura jamaicensis) killed in an oil spill on 

 the Delaware River (White and Kaiser 1976), 

 contained DDE (1.1-4.5 ppm) and PCB's (2.8- 

 10 ppm). Levels of DDT and DDD were below 



