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Predictable and unpredictable spawning events: in situ behavioural data from free-spawning coral reef invertebrates

journal contribution
posted on 2023-05-18, 11:43 authored by Babcock, R, Craig MundyCraig Mundy, Keesing, J, Oliver, J
We describe the spawning behaviour and some aspects of spawning periodicity in a diverse group of marine invertebrates, principally echinoderms, but including sponges, anthozoans, molluscs, and polychaetes. Our observations were made both opportunistically and on a systematic basis between 1978 and 1992 on the central and northern Great Barrier Reef. Spawning was predictable in some of the species observed, for example Bohadschia argus, Euapta godeffroyi, and Stichopus variegatus (Holothuroidea), which exhibited regular lunar and diel periodicity. Others, such as Holothuria coluber, Actinopyga lecanora, and Bohadschia graffei (Holothuroidea), Acanthaster planei (Asteroidea), Hyotissa hyotis and Arca spp. (Bivalvia) exhibited no clear lunar or diel periodicity in spawning behaviour. Mass heterospecific spawnings which involved several species, often from different phyla, were commonly observed. The species participating were usually those with unpredictable spawning patterns and while the species involved were diverse there were also occasions when spawning involved species from the same genera. Fertilization rates were measured in situ for the predictable spawner Bohadschia argus and were found to vary between 0–96% depending on the circumstances of the spawnings. Fertilization rates for the unpredictable spawners showed similar variability; Holothuria coluber and Actinopyga lecanora ranged from 9–83%.


Publication title

Invertebrate Reproduction and Development










Institute for Marine and Antarctic Studies


Taylor & Francis

Place of publication

United Kingdom

Rights statement

© 1992 Balaban

Repository Status

  • Restricted

Socio-economic Objectives

Marine biodiversity

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