The effect of crowding and density on male mating behaviour in the rose bitterling (Rhodeus ocellatus)

0345138 - ÚBO 2011 RIV NL eng J - Journal Article
Casalini, M. - Reichard, Martin - Smith, C.
The effect of crowding and density on male mating behaviour in the rose bitterling (Rhodeus ocellatus).
Behaviour. Roč. 147, č. 8 (2010), s. 1035-1050. ISSN 0005-7959. E-ISSN 1568-539X
R&D Projects: GA ČR GA206/09/1163
Institutional research plan: CEZ:AV0Z60930519
Keywords : density-dependence * mating system * sexual selection * sperm competition * territoriality
Subject RIV: EG - Zoology
Impact factor: 1.480, year: 2010

Female density and resource availability are two key variables that shape mating systems. Here we tested mean crowding, defined as the number of males per unit of resource, and density per se, defined as the number of individuals present per unit area, to investigate their effect on the mating system of Rhodeus ocellatus. Males were exposed to combinations of high and low levels of crowding and density, while the operational sex ratio was held constant. High levels of crowding significantly affected the proportion of mussel spawning sites defended by males and the proportion of mussels into which sperm was released. In contrast to theoretical predictions, neither density nor crowding influenced overall male aggressive behaviours. Density, but not crowding, had a significant effect on male courtship rate, which arose as a possible trade-off between intra-sexual competition and inter-sexual behaviour.
Permanent Link: http://hdl.handle.net/11104/0186473