Ecological adaptation in the Galápagos sea lion: The role of foraging ontogeny and interspecific competition

加拉帕戈斯海狮的生态适应：觅食个体发育和种间竞争的作用

• 批准号: 81016557
• 负责人: Professor Dr. Fritz Trillmich
• 金额: --
• 依托单位: Arbeitsgruppe Verhaltensforschung
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2008
• 资助国家: 德国
• 起止时间: 2007-12-31 至 2011-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/81016557?language=en
• 关键词: Ecological; adaptation; Gal; pagos; sea

Environmental conditions during early development greatly influence later habitat choice, foraging behavior, and settlement patterns of juvenile animals. Such early influences may enable ecological separation within a population. We have previously demonstrated differences in food choice, morphology of the feeding apparatus, and genetic make-up of Galapagos sea lions (GSL; Zalophus wollebaeki) from the western and central populations of the archipelago. Such differences were unexpected given the high mobility of this species relative to its small geographical range. This difference between the western and central population may be caused by habitat differences as well as competition with Galapagos fur seals (GFS; Arctocephalus galapagoensis) that occur predominantly in the west. We here suggest to study the development of foraging behavior and area-use by young sea lions as well as potential competition with fur seals to determine the contribution of environmental differences during ontogeny to ecological adaptation in western and central populations. This should show how habitat use correlates with differences in foraging and how these differences become established during ontogeny. In addition, the study will determine the role of foraging ontogeny for juvenile survival and if competition with the sympatric GFS can explain that the western GSL population that lives in more productive waters is less abundant than that in the less productive central area. The study will thereby contribute to understanding the role of ontogenetic experience and interspecific competition for habitat choice, population dynamics, and the early stages of speciation.

早期发育的环境条件对幼年动物后期的栖息地选择、觅食行为和定居模式有很大影响。这种早期的影响可能会使种群内的生态分离。我们以前已经证明了食物选择的差异，形态的喂养器具，和遗传组成的加拉帕戈斯海狮（GSL; Zalophus wollebaeki）从西部和中部的群岛人口。这种差异是出乎意料的，因为相对于其小的地理范围，该物种的流动性很高。西部和中部种群之间的这种差异可能是由栖息地差异以及与主要发生在西部的加拉帕戈斯毛皮海豹（GFS; Arctocephalus galapagoensis）的竞争造成的。在这里，我们建议研究觅食行为和区域使用的年轻海狮的发展，以及与海狗的潜在竞争，以确定在个体发育过程中的环境差异，在西部和中部人口的生态适应的贡献。这应该表明栖息地的使用与觅食的差异以及这些差异如何在个体发育过程中建立。此外，这项研究将确定的作用，觅食个体发育的少年生存，如果竞争与同域的GFS可以解释，西部GSL人口，生活在更富有成效的沃茨是不太丰富的生产力较低的中心地区。因此，这项研究将有助于了解个体发育的经验和种间竞争的栖息地选择，种群动态和早期阶段的物种形成的作用。