These seastars move towards light.
The adults are mobile with a top speed of 20 cm/minute.
Tagged seastars in Tokyo Bay, Japan, logged maximum travel distances 2.5 km in 32 days (78m/day) in the west of the bay, and 8.1 km in 129 days (62.8m/day) at the east.
The population goes through boom-and-bust cycles in Japan, where it can swarm on occasions; during swarms the adults can float on the sea surface due to air retained within the body cavity.
The population is mixed, with different age groups found intermingled.
The animals can survive at least four years in the wild in Japan, but it is estimated that most live to two to three years.
If the seastar is ripped apart, each arm can grow into a new animal (fissiparity) if a part of the main disk is attached.
This is not entirely uncommon.
These seastars move towards light. The adults are mobile with a top speed of 20 cm/minute. Tagged seastars in Tokyo Bay, Japan, logged maximum travel distances 2.5 km in 32 days (78m/day) in the west of the bay, and 8.1 km in 129 days (62.8m/day) at the east. The population goes through boom-and-bust cycles in Japan, where it can swarm on occasions; during swarms the adults can float on the sea surface due to air retained within the body cavity. The population is mixed, with different age groups found intermingled. The animals can survive at least four years in the wild in Japan, but it is estimated that most live to two to three years. If the seastar is ripped apart, each arm can grow into a new animal (fissiparity) if a part of the main disk is attached. This is not entirely uncommon.
Asterias amurensis