Ota Kazutaka, Aibara Mitsuto, Morita Masaya, Awata Satoshi, Hori Michio, Kohda Masanori
Department of Zoology, Kyoto University, Kitashirakawa-Oiwake, Sakyo, Kyoto 606-8502, Japan.
Int J Evol Biol. 2012;2012:193235. doi: 10.1155/2012/193235. Epub 2012 Jul 19.
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.
在坦噶尼喀湖的几种口育丽鱼中发现了替代繁殖策略（ARTs）。我们在翁齐耶种群中进行了实地研究，以考察坦噶尼喀湖口育丽鱼短身新亮丽鲷的繁殖生态学和替代繁殖策略。我们发现这种鱼出现在岩石底和沙地栖息地，但在岩石栖息地，育雏雌鱼只出现在另一种丽鱼科鱼类创造的贝壳聚集区。聚集区内的所有短身新亮丽鲷雌雄个体均已性成熟，而未成熟的雄鱼和卵巢未成熟的雌鱼在沙地栖息地很常见。沙地栖息地的雄鱼体型较小，但进食更频繁，且身体状况比聚集区内的雄鱼更好。雌鱼也有类似的趋势。这表明短身新亮丽鲷根据其生活史阶段利用不同的栖息地，会从沙地栖息地迁移到贝壳聚集区进行繁殖。聚集区内的雄鱼表现出不同的行为模式：在聚集区上方游动和躺在聚集区内。前者体型更大、更具攻击性，且相对于体型而言性腺投入较少。这些结果与其他具有替代繁殖策略的坦噶尼喀湖口育丽鱼的结果一致，因此表明短身新亮丽鲷存在替代繁殖策略。
