| Budget Amount *help |
¥6,700,000 (Direct Cost: ¥6,700,000)
Fiscal Year 1986: ¥1,400,000 (Direct Cost: ¥1,400,000)
Fiscal Year 1985: ¥5,300,000 (Direct Cost: ¥5,300,000)
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| Research Abstract |
Feral pigeons Culumba livia var: are a handy and sensitive biological indicator of urban environmental pollution and ubiquitously found in metropolitan areas. In recent years, polychlorinaited dibenzo-p-dioxins (PCDDs) some of which are known to be quite toxic, have been reported to be present in flyash discharged from incinerators. In order to see that PCDDs found in pigeons have originated from an incinerator, we analyzed feral pigeons in a vicinity of an incinerator as well as the ones in downtown Tokyo for PCDDs. We found that octa-CDDs in pigeon adipose tissue or liver ranged from 1-3 ug/kg fat; the concentration of OCDDs was higher in adult pigeons than in young birds. Hepta-CDDs were found about 1/2 to 1/3 of OCDDs and their level was again higher in adult pigeons than in young ones. 2,3,7,8-tetra-CDD, the most toxic delivertive, was found to be too minute to allow quantitative analysis. Since the pattern of PCDD isomers in flyash from incinerator was different from that noted in the adipose tissue of the pigeons, it was assumed that PCDDs in the pigeons have either originated from a source other than the incinerator or represented metabolites of PCDDs in the flyash.
Feral pigeons are often regarded as a nuisance because of their being a possible source of biological pathogens. We found that the prevalence rate of Chlamydia in a pigeon colony was 40% in an industrial area, 20-30% in a residential area and in the suburb of Nagoya, and 30% at Sensoji Temple in Tokyo, suggesting there is no siginificant geographic differences.
Finally, we studied the influence of light on the life pattern of pigeons and also the relations among the reproductive activities, age and nesting conditions.
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