ABSTRACT: A simple device is described that can be used to collect the eggs of free-spawning marine invertebrates and that is cheap, portable and fool-proof. The air-displacement sampler was used to collect eggs from female sea urchins, Heliocidaris erythrogramma, downstream from experimentally induced spawning males. Average fertilisation rates of eggs decreased downstream and were 87, 48, 40, 17 and 7% at 10, 100, 200, 400 and 1000 cm respectively.

KEY WORDS: Fertilisation ecology · Sampling · Sea urchin · Heliocidaris · Marine invertebrate

Published in MEPS Vol. 150 (1997) on April 30
ISSN: 0171-8630. Copyright © Inter-Research, Oldendorf/Luhe, 1997