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K. G. HAY 



cleaned and farmed out for rehabilitation. Re- 

 ports show that many of the birds were re- 

 turned dead within a few days (Smithsonian 

 Institution 1971). 



In 1971, when two tankers collided under 

 the Golden Gate Bridge at the mouth of San 

 Francisco Bay, the resulting spill involved 

 some 4,686 oiled birds taken to cleaning cen- 

 ters (Lassen 1972). Eight months later the 

 last of 200 survivors (less than 5%) were re- 

 leased at a cost estimated at $900 per bird 

 (Smith 1975). 



The most vulnerable species involved in 

 spills have been the oceanic birds such as the 

 alcids murres (Uria spp.), auks (Pinguinus 

 spp., Alca spp.), puffins (Fratercula spp., 

 Lunda spp.), and guillemots (Cepphus spp.). 

 Other species less affected included ruddy 

 ducks (Oxyura jamaicensis), scaup (Ay thy a 

 marila, A. affinis), scoters (Melanitta spp.), 

 mergansers (Lophodytes spp.), oldsquaws 

 (Clangula spp.), and goldeneyes (Bucephala 

 spp.). Grebes (Podiceps spp.), eiders (Poly- 

 sticta spp.), loons (Gavia spp.), and cor- 

 morants (Phalacrocorax spp.) are also fre- 

 quently involved. Ruddy ducks and scaup are 

 particularly vulnerable during winter on large 

 river systems with heavy oil transport traffic. 

 Fortunately, none of the above species have 

 been reported in jeopardy as a result of spills 

 in American waters. 



In Europe and South Africa, however, it is 

 believed that oil pollution is responsible for a 

 steady decline in seabird colonies. For 

 example, in known oil-dumping areas in the 

 Baltic Sea, where some mortality of old- 

 squaws has been associated with surface oil, 

 their population has dropped to about one- 

 tenth of the pre- World War II level (Bergman 

 1961). Other authors report that oil spills 

 have reduced the number of scoters in the Bal- 

 tic and off southeast England (Atkinson- 

 Willes 1963). The auk populations off the 

 coast of England have been reported to be 

 substantially decreased by oil pollution (Pars- 

 low 1967). Tankers traversing South Africa's 

 Cape of Good Hope are said to be responsible 

 for the reduction of jackass penguins, 

 Spheniscus demersus (Rowan 1968). Oil pollu- 

 tion, especially sustained pollution, has thus 

 been cited as a limiting factor on certain sea- 

 bird populations. 



Estimates of seabird mortalities from an oil 



spill are imprecise; they may differ by thou- 

 sands of birds. It is believed that only a small 

 fraction of the birds killed in a spill wash up 

 on the shore. Some authors have even specu- 

 lated that the death rate at sea could range 

 from 6 to 25 times the number washed ashore 

 (Tanis and Morzer-Bruyns 1968). 



In contrast to terrestrial birds and semi- 

 aquatic species (e.g., ducks; geese; coots, 

 Fulica spp.; or gulls, Lams spp.), totally sea- 

 borne species have a restricted reproductive 

 potential. Many, such as the alcids, do not 

 breed until they are 3 or more years old, and 

 lay only one egg per year. Only one in five sur- 

 vives to go to sea. 



Until about 5 years ago we knew little about 

 seabirds. They are not game species (they 

 taste fishy) and thus do not constitute an im- 

 portant economic resource. They have never 

 been the subject of intensive waterfowl man- 

 agement or research by either State or 

 Federal governments. 



During the last 5 years a small group of 

 people here and in England have been study- 

 ing marine birds their distribution, popula- 

 tion status, physiology, diseases, and hus- 

 bandry in captivity. Four organizations have 

 primarily been involved: The American Petro- 

 leum Institute (API); the Wildlife Rehabilita- 

 tion Center at Upton, Massachusetts; Eng- 

 land's Advisory Committee on Oil Pollution 

 of the Sea; and the International Bird Rescue 

 Research Center in Berkeley, California. They 

 have encountered many common biological 

 and people problems, some of which I discuss 

 here. 



Biological Problems 



The recuperation record for oiled seabirds in 

 the past has admittedly been dismal. A few 

 birds have been returned to nature, but only 

 after a long and costly period of care. In the 

 process, semidomestication often takes place. 

 The percentage of cleaned birds that actually 

 survive after release is even smaller. One 

 should not infer from this small percentage 

 that rehabilitated birds cannot readjust to life 

 in the wild. Several successful reintroductions 

 have been documented. U.S. Fish and Wildlife 

 Service bands were returned from two west- 

 ern grebes that were cleaned and released 



