Mass destruction of Synthliboramphus antiquus by oil pollution of Japan Sea

Abstract

The author first noticed in 1959 the shore washed sea birds on the beach of Kashiwazaki, Niigata prefecture and has reported, since 1964, Synthliboramphus antiquus, Uria lomvia, Brachyramphus marmoratus, Cerorhinca monocerata, Lunda cirrhata, Aethia psittaculus, Rissa tridactyla, Larus argentatus, Calonectris leucomelas, Gavia stellata and Gavia arctica, found dead by oil pollution. Alcids are especially affected by the pollution and the Ancient auklet, Synthliboramphus is the most usual species.
In this report, 30 examples of this auklet were selected for anatomical analysis. On 24 January 1971 numerous dead ones contaminated black by oil were found along, 280km of the beach, 5 birds in 100m at a certain part. They could be grouped into 3 categories with respect to the body weight, amount of fat and oil attached. The most severely polluted example had oil weight 50% of the body weight with least fat. Others still had some fat. The oil was found even in the digestive tract.
The ship oil is still being casted offshore in Japan Sea but is drifted ashore by prevailing winds. After much effort by the author and others, the problem became seriously considered but no definite solution is reached yet.