Thirteen examples of
Corvus levaillantii japonensis obtained in Tokyo, May 27, 28, 1969, were measured, and examined anatomically.
1. Sex ratio was even, being 6_??__??_, 7_??__??_, and one of the each sex retained Bulsa of Fabricius (the famale example examined still showed a small non-pneumatic part of the skull). These, and perhaps one other male, were young of the previous year. Others were probably non-breeding 2nd year subadults, having little developed gonads in this season (Least developed in the above young of the year). One of the famale was a breeding adult having incubation patch.
2. They had little or almost no fat, except one young male which ate more animal food.
3. Body weight and all external measurements were larger in the male, and this difference was expressed by 'sexual index', S. I. which is: smaller measurement/larger measurement % (positive value in _??_>_??_, and negative in _??_>_??_), and its significance was discussed. This index ranged 88.94% (Body weight)-98.33% (Tail 1.) and all were positive.
4. In one example, the total pectoralis was 14.82% of body weight, the femoral muscles 5.66% and tibial 5.50%.
5. Length of intestine was average 882.0mm in 5_??__??_, 895.7mm in 7 _??__??_ and 'intestine index',
3√body weight/length of intestine, was calculated, which was 0.101 in the male and 0.100 in the femal. The caeca were 15-16mm. The gizzard was av. 38×28mm in size and 10.5g (1.4% of body weight) and the liver in one example was 2.74% of body weight.
6. Most gizzard and intestine (4 examples examined) contained cherry berries (their stones) with other items such as toad's part, beetles, pigeon eggshell, bird feathers and animal hairs (probably chair material) or cake piece, etc. In observation toad and rat are favored food items beside human food debris.
7. Two species of Cestodes,
Passerilepis sp. and
Raillietina sp. were found in all of four intestines examined (not found in the gizzard) and the numbers were counted by individual length and by its sum, i. e.: the 'total parasite length'. Younger bird (with Bulsa of Fabricius) had total parasite length of only 10cm and the intestine was clean, while others had from 85cm (scattered along the intestine wall), 137.2cm (clustered at the middle) to 191.7cm (found as two clusters) in an adult female with incubation patch. The individual length was also increasingly longer.
8. The parasite's number and total parasite length thus increase with the age of the bird and this might affect the bird's longevity or mortality. The
Acanthocephala usually to be found in suburban crows (possibly
C. corone) was not found and this reflects that
C. levaillantii in Tokyo is permanent resident within the city zone.
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