ABSTRACT: Behavioural responses of 2 Baltic benthic crustaceans to chemical substances from predators were studied using infrared video-recording in the laboratory. This is the first study of behavioural responses to species-specific chemical substances in a 3-trophic-level food chain. Exposure to chemical substances from a predatory fish, the short-horned sculpin Myoxocephalus scorpius (L.), caused the isopod Saduria entomon (L.) to remain buried in the sediment most of the time and decreased its foraging success on the amphipod Monoporeia affinis (Lindström). M. affinis decreased its swimming activity when exposed to water from S. entomon feeding on M. affinis, whereas water from unfed S. entomon had no such effect.

KEY WORDS: Chemical cues · Three-trophic-level food chain · Monoporeia affinis · Saduria entomon · Fish · Benthos · Behaviour · Baltic Sea

Published in MEPS Vol. 165 (1998) on May 7
ISSN: 0171-8630. Copyright © Inter-Research, Oldendorf/Luhe, 1998