大阪湾におけるジャノメガザミの生活史 [in Japanese] Life History of the Red-spotted Swimming Crab Portunus (Portunus) sanguinolentus in Osaka Bay [in Japanese]
Access this Article
Search this Article
To clarify the life history of the red-spotted swimming crab Portunus (Portunus) sanguinolentus in Osaka Bay, many crabs were collected from drifting seaweed and in coastal and offshore areas. In addition, the carapace widths of fishermen-caught crabs were measured, catches by fishermen were recorded, and rearing experiments were carried out. The crabs were seen only from June to January in Osaka Bay. The life history of most crabs is reconstructed as follows. Juvenile crabs arrive from the Kii Channel after attaching themselves to drifting seaweed. They grow rapidly and their average carapace widths (including lateral spines) in winter reach about 140 mm for males and 130 mm for females. Ovigerous females appear from August to January, but these scarcely contribute to total reproduction. When the water temperature falls to below ca. 12°C, all crabs die.These characteristics suggest that the introduction of crabs into Osaka Bay occurs through non-effective dispersal.
- Japanese Journal of Benthology
Japanese Journal of Benthology 51(1), 1-8, 1996-07-29
JAPANESE ASSOCIATION OF BENTHOLOGY