THE TRADE-OFF BETWEEN FEEDING, MATE SEEKING AND PREDATOR AVOIDANCE INCOPEPODS - BEHAVIORAL-RESPONSES TO CHEMICAL CUES

The behavioural responses of adult Temora longicornis to chemical sign als from predators and potential sexual partners was studied using an automated three-dimensional (3-D) tracking system and a 2-D high-resol ution filming set-up. The animals adapted their swimming speed and tur ning behaviour in reaction to chemical signals to increase or decrease encounter probability with other organisms. Female copepods were show n to react to the smell of males with little 'hops', quite distinct fr om bath their normal smooth swimming motion and escape responses. Thes e hops are likely to be signals intended to increase the encounter pro bability with males. Swimming behaviour was shown to be a trade-off be tween conflicting motivations such as predator avoidance on the one ha nd, and the search for food and sexual partners on the other.