PPOTENTIAL PRE-MATING BEHAVIOR IN IMMATURE TOMATO ANEMONEFISH (AMPHIPRION FRENATUS) UNDER CULTURE CONDITIONS

By

Ryan Thomas Sacksteder

Abstract

Amphiprion frenatus is a species of tropical reef fish popular as an aquarium fish. The current methods of capturing such fish in the wild, however, can create environmental strains. In order to alleviate these strains, culture conditions and A. frenatus mating patterns need to be better understood. The objective of this study was to monitor and describe the behaviors of paired immature members of A. frenatus to be compared with the behaviors of a mature, mating pair, with the goal of identifying bonding, pre-mating, and nesting behaviors under aquarium conditions. The behaviors monitored included five aggressive non-bonding behaviors, three submissive non-bonding behaviors, five pre-mating bonding behaviors, and one neutral behavior. Ten of those behaviors could be displayed by either individual in the pair and were thus counted as two separate behaviors (for example, ‘tail-dig L’ for the larger fish and ‘tail-dig S’ for the smaller), for a total of 24 possible behaviors. Ten of the possible twenty-four behaviors were observed in sufficient numbers to be analyzed statistically and included one aggressive non-bonding, one neutral, and eight pre-mating bonding behaviors. The immature pairs that displayed the most similar behaviors to the mature, mating pair were the largest pairs and/or the pairs with the longest duration of time since being introduced, while the younger, smaller pairs’ behaviors differed the most from those of the mature pair. There was a trend away from aggressive behaviors as dominance was established and a shift of behavior towards pre-mating and nest preparation. Observations of behavior can thus be used as possible indicators of a pair’s level of maturity and potential breeding status.