Table of Contents
International Journal of Evolutionary Biology
Volume 2012 (2012), Article ID 193235, 10 pages
http://dx.doi.org/10.1155/2012/193235
Research Article

Alternative Reproductive Tactics in the Shell-Brooding Lake Tanganyika Cichlid Neolamprologus brevis

1Department of Zoology, Kyoto University, Kitashirakawa-Oiwake, Sakyo, Kyoto 606-8502, Japan
2Department of Biology and Geosciences, Osaka City University, Sugimoto, 3-3-138 Sumiyoshi, Osaka 558-8585, Japan
3Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama 226-8501, Japan
4Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato, Hakodate, Hokkaido 041-8611, Japan
5TBRC Sesoko Station, University of the Ryukyus, 3422 Sesoko, Motobu, Okinawa 905-0227, Japan
6Sado Marine Biological Station, Niigata University, 87 Tassha, Sado, Niigata 952-2135, Japan

Received 13 March 2012; Revised 22 May 2012; Accepted 29 May 2012

Academic Editor: Kristina M. Sefc

Copyright © 2012 Kazutaka Ota et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Alternative reproductive tactics (ARTs) are found in several Lake Tanganyika shell-brooding cichlids. Field studies were conducted in the Wonzye population to examine reproductive ecology and ARTs in the Lake Tanganyika shell-brooding cichlid Neolamprologus brevis. We discovered that this fish occurred in both rocky- and sandy-bottom habitats, but in rocky habitats, brood-caring females exclusively occurred in shell-patches that another cichlid species created. All N. brevis of both sexes in the patches were sexually mature, whereas immature males and females with unripe eggs were found frequently in sandy-bottom habitats. Males in sandy-bottom habitats were smaller, but fed more frequently and were in better somatic condition than males in the patches. Similar tendency was found in females. This indicates that N. brevis uses different habitats depending on the stage of its life history, with migration from sandy-bottom habitats to the shell-patches for reproduction. Males in the patches exhibited different behavior patterns: floating above the patches and lying in the patches. The former was larger, more aggressive, and invested less in gonads (relative to body size) than the latter. These results accord with those of other shell-brooding Lake Tanganyika cichlids with ARTs, and they therefore suggest the presence of ARTs in N. brevis.