The Antipredation Behaviour Of The Golden Apple Snail (Pomacea Canaliculata) With Different Age

In aquatic environments,predator effects on aquatic organisms through direct consumption or on arousing avoidance behavior of the prey,where the prey reduces feeding or breeding time. Therefore predator causes a higher loss of fitness to the prey. Aquatic organisms show anti-predator behavior when receiving the signal released by injury-individual. Anti-predator behavior is an adaptive response against predation in order to enhance fitness. For example, freshwater molluscs response to shell-breaking predators by crawling out of water. In different environments, the organism may adopt various alternative phenotypes to enhance the possible fitness. In a given period, whether anti-predator response of the same pomacea canaliculata individual will continously present, when encounters the injuried individual is unknown.In this study, I performed a series of experiments with golden apple snails hatched from 20 egg masses. Using the suspension of the injury-individauls of the same golden apple snail lineage as signal source, I observed anti-predator behavior showed by each individual at its age of 1, 3, 5, 7, 9, 11, 17, 21, 36 days. The results showed: 1, the response rate increased drastically and then slowly declined to complete non-response; 2, for juvenile snails, the expression of this strategy of defense, i.e. the anti-predator behavior is unequally distributed among juveniles from different lineages. 3, generally juvenile snails tend to choose inactive strategy rather than active strategy (active: inactive= 1:3); 4, the strategies used by juveniles are lineage-specific.