The effect of conspecific density on female reproduction in an egg-carrying bug

The availability of high-quality egg-laying substrates is likely to determine female reproductive success in insects. The egg-laying substrate may also be a conspecific, which is the case in the golden egg bug Phyllomorpha laciniata, Vill. Female bugs oviposit mainly on nonparental males and other females. Conspecifics are clearly preferred to the bug's food plant. We tested the effect of conspecific density, on female egg laying in two experiments where an egg-laying focal female was accompanied by males, females or both in two sizes of enclosures for 8 days. Fewer eggs were laid in large enclosures than in small ones and an increase in number of conspecifics resulted in more eggs being laid on them. This study shows that conspecifics are an important resource for female golden egg bugs in terms of egg laying. In addition, egg survival is likely to be affected by the female's chances of laying eggs on conspecifics. (C) 2004 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.