Collaborative Research: Can Larvae Utilize Dissolved Settlement Cues in the Wave-Driven Flow on Coral Reefs?

Koehl 9907120本项目的目的是确定是否水传播的化学线索可以影响栖息地受到波浪驱动的水流，许多沿海栖息地的特点，底栖海洋无脊椎动物的幼虫的解决方案。这一问题将通过研究裸鳃Phestilla sibogae来解决，其幼虫因其猎物的一种特定物种的代谢物而变形，这种猎物是一种丰富的珊瑚，在夏威夷的浅水、波浪为主的生境中形成珊瑚礁。经过充分研究的吃珊瑚的裸鳃类动物P. sibogae将作为生活在珊瑚礁上的底栖无脊椎动物的模型，并依靠从浮游生物中招募幼虫来发现和补充种群，并在小距离和大距离上保持遗传连续性。Hadfield在幼虫生物学方面的专业知识将与Koehl在生物力学和Koseff在环境流体力学方面的专业知识相结合，以解决以下问题：（1）环境水流如何分散自然界中溶解的线索？ (2)在平流和混合溶解的线索低的微生境中，西博盖蚤幼虫是否在野外招募？ (3)在波浪驱动的水流中，P. sibogae的幼虫对水传播的线索的反应是否会影响它们在珊瑚礁上的保留和定居？这种机制的作用，溶解的线索在幼虫定居在暴露于波驱动流的网站的研究超越了这种过程中的单向流动的早期研究。刚性冠层形成生物体对沿海生境小规模流动和质量运输的影响的调查补充了柔性大型植物冠层的类似研究，也补充了珊瑚礁的大规模流动研究。该项目对幼虫生态和（幼虫补充过程可对种群的动态和遗传结构以及沿海底栖生境的群落结构产生深远影响）和珊瑚礁生态（珊瑚礁结构可改变水生营养物、食物、废物和繁殖体向生活在这些重要热带生态系统中的生物群落的小规模流动和运输）。

Koehl 9907120The objective of this project is to determine whether water-borne chemical cues can affect the settlement of larvae of benthic marine invertebrates in habitats subjected to the wave-driven water flow that characterizes many coastal habitats. This question will be addressed by studying the nudibranch Phestilla sibogae, whose larvae metamorphose in response to a species-specific metabolite of its prey, Porites compressa, an abundant coral that forms reefs in shallow, wave--dominated habitats in Hawaii. The well-studied coral-eating nudibranch P. sibogae will serve as a model for benthic invertebrates that live on coral reefs and rely on recruitment of larvae from the plankton to found and replenish populations and maintain genetic continuity across small and large distances. The expertise of Hadfield in larval biology will be combined with that of Koehl in biomechanics and Koseff in environmental hydrodynamics to address the following questions: (1) How does ambient water flow disperse dissolved cues in nature? (2) Do P. sibogae larvae recruit in the field in microhabitats where advection and mixing of dissolved cues is low? (3) Do larvae of P. sibogae respond to water-borne cues in ways that affect their retention and settlement on a reef in wave-driven water flow? This mechanistic study of the role of dissolved cues in larval settlement at sites exposed to wave--driven flow goes beyond earlier studies of such processes in unidirectional flow. This investigation of the effects of rigid canopy-forming organisms on small-scale flow and mass transport in coastal habitats complements similar studies in flexible macrophyte canopies, and also complements larger--scale flow studies of coral reefs. The project has a potential impact on both larval ecology (larval recruitment processes can have profound effects on the dynamics and genetic structure of populations, and on community structure in coastal benthic habitats), and on coral reef ecology (reef structure can alter the small-scale flow and transport of water-born nutrients, food, wastes, and propagules to the community of organisms living in these important tropical ecosystems).***