The unfortunate encounter between spilled oil and marine birds is not new. It goes back at least to the turn of the century, when coal-burning steamships and sailing clippers were replaced by oil-fueled vessels. Since then thousands of marine birds have succumbed to floating oil, especially during World Wars I and II (Blanks 1942) and in recent spills here and off the coast of Europe (Clark 1969).
With the current and projected demands for energy in the United States and with expanded tanker traffic and accelerated development of offshore petroleum reserves, the oil-contaminated ("oiled") bird is not going to go away. Periodically, this ugly problem will arise, despite the efforts of the petroleum industry to improve its safety practices, engineering, and navigational skills. Unfortunately, the problem is the product of the inherent fallibility of man and his imperfect machines.
We cannot ignore the situation. We must here, as elsewhere, improve our technology and mitigate the impact.
A study of more than 100 spills that occurred throughout the world between 1960 and 1971 revealed that about 1 in 5 spills (20%) involved 50 or more birds (Ottway 1971). Nearshore spills have a far greater effect on waterfowl than do spills occurring several miles or more offshore.
In the 1967 Torrey Canyon tanker spill, some 8,000 oiled birds were rescued. About 6,000 were picked up alive in England and about 2,000 in France, at a cost estimated at $160,000 (Clark 1969; Bourne 1970). Less than 5% of those treated by British authorities survived for release some months later. The survival rate of those rescued in France is unknown.
In 1969 the Santa Barbara spill resulted in the treatment of 1,575 marine birds, of which 169 were eventually released. Many of those released were found dead within a short time (Smail 1971).
In 1970 the tanker Delian Apollon was responsible for a spill in Tampa Bay, Florida. Thousands of seabirds were lost. No exact count was taken, but hundreds of birds were cleaned and farmed out for rehabilitation. Reports show that many of the birds were returned 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 centers (Lassen 1972). Eight months later the last of 200 survivors (less than 5%) were released 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 (Aythya marila, A. affinis), scoters (Melanitta spp.), mergansers (Lophodytes spp.), oldsquaws (Clangula spp.), and goldeneyes (Bucephala spp.). Grebes (Podiceps spp.), eiders (Polysticta spp.), loons (Gavia spp.), and cormorants (Phalacrocorax spp.) are also frequently 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 oldsquaws 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 Baltic 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 (Parslow 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 pollution, especially sustained pollution, has thus been cited as a limiting factor on certain seabird populations.