Flying crabs adapt to water temperatures of 8~31℃, and the optimal water temperature for growth is 15.5~26.0℃. In different water temperature environments, the activities of Portunus trituberculatus are different. When the water temperature is ~1.5°C, they do not eat, and some individuals freeze to death in shallow water areas; when the temperature is 0~6°C, they do not eat, and they lurk in the sand day and night, showing a state of resting eyes; when the temperature is 8~10°C, they do not eat. It begins to stop eating, has weak activity, and lurks in deep water; at 14°C, the food intake decreases, and begins to move to deep areas, and the activity is normal; at 15~26°C, the food intake is large, and the activity is normal Normal and fast growing; mating peaks at 17~21°C; egg-bearing groups begin to be found at 14~21°C; spawning begins at 12~14°C; when the water temperature is below 10°C and above 32°C, The swimming crab stops feeding.

Extended information:

Life habits

Flying crabs lurk on the seabed during the day and come out to look for food at night and have obvious phototaxis. Flying crabs raised in ponds have obvious diurnal vertical movement at sunrise and sunset.

When the flying crab swims, its body tilts and hangs upside down in the water, and its feet swing frequently in the fifth step, swimming horizontally or undirectionally. When diving into the mud and sand, it is often at an angle of 15 to 45 degrees with the bottom of the pool, with only its eyes and antennae exposed.

Flying crabs have no ability to drill holes, so there is no need to set up defense and escape facilities for pond farming. When the water temperature is below 18°C, swimming crabs mostly lurk in the sand piles beside the pond.