Meeting Abstract

P3-56  Monday, Jan. 6  Nest size and 11-ketotestosterone in bluegill sunfish (Lepomis macrochirus) HAIN, TJA*; CHURCHMAN, EKL; KNAPP, R; NEFF, BD; University of Western Ontario, London, ON; University of Western Ontario, London, ON; University of Oklahoma, Norman OK; University of Western Ontario, London, ON tjhain@uwo.ca

In some species, males congregate on breeding grounds (leks) to attract females, mate with them, and provide only genes to their offspring. In such breeding systems, a small number of dominant males acquire the vast majority of matings by virtue of their size and superior genes. Bluegill (Lepomis macrochirus) offer an interesting variation on the lek mating system. In bluegill, males form colonies of nests and attract females, spawn with those females, then provide care to the developing young. In mating systems with direct benefits such as in bluegill, females are expected to choose mates who can provide high-quality care. However, the cues that females use to choose mates are largely unknown. In this study, we measured nest size in a bluegill colony and examined if the depth or area of nests could reliably inform females about a male’s body size or 11-ketotestosterone (11-KT) levels, which are important characteristics in nest defence. We found that the colony had 4-fold variation in nest area and 3-fold variation in nest depth and that the nest depth was strongly correlated with nest area. However, neither depth nor area was correlated with body size or 11-KT. We suggest that nest size is not a reliable indicator of body size or 11-KT and that females either use other, more reliable signals of male quality, or assess quality directly.