On traffic accidents of birds on Ise highway, Mie Prefecture

Abstract

1. Bird accidents recorded during 1965-1972 on highway passing 8km through the warm zone mixed forest of Ise Shrine ground were investigated 563 times in total.2. This highway, with the width of 6.5m had a traffic of average 1, 500 cars/day in 1965 when it was opened. The traffic increased about 3.5 times by 1972 and the bird accidents (the annual relative kill) also increased 3.2 times during these 8 years.3. The frequencies of No. bird kill/No. observation were 2/48 (1965), 6/120 (1966), 8/118 (1967), 8/95 (196), 8/80 (1969), 5/65 (1970), 5/37 (1972), with the total of 42 birds killed/365 observations (1965-1972), and increase from 7.4% annual relative kill in 1965 to 23.5% in 1972.4. Bird accidents included 10 families, 18 species, comprising 72.2% residents, 16.7% winter visitors and 1/3 of the total of 42 kills were young birds.5. The species of highest kill rate was 21.4% of redstart Phoenicurus auroreus, the 14% of Emberiza cioides, 7.1% of Cettia diphone, Parus varius and Streptopelia orientalis etc. and ground feeding Turdus included three species.6. Seasonally, the highway kill of 19% of the total in March was the highest and the monthly kill was 10% during November to February, the winter kills from November to April occupying 87% of the total, which was about 3 times more frequent than in summer period.7. The cause of death confirmed included 33% cranial internal hoemorrhages, and 14% visceral haemorrhages, which were caused by liver or even aortic breaks.8. The accidents of birds were concentrated at 9 places along the highway of 8km. At these points small valley (s) with the width of 2-5m crossed the road at right angle, but at a broad open cross point of two big roads birds that move by low flight, such as bush warbler, pale ouzel, etc., were found dead.9. Some observations showed that road-side birds would take off with the speed of 30-60km/h, and car speed retained at about 40km/h may usually be safe for the birds from being struck at.