Data from: Differential persistence favors habitat preferences that determine the distribution of a reef fish

A central focus of population ecology is understanding what factors explain the distribution and abundance of organisms within their range. This is a key issue in marine systems, where many organisms produce dispersive larvae that develop offshore before returning to settle on benthic habitat. We investigated the distribution of the neon goby, Elacatinus lori, on sponge habitat and evaluated whether variation in the persistence of recently settled individuals (i.e., settlers) among different sponge types can result in habitat preferences and establish their observed distribution. We found that E. lori settlers were more likely to occur on large yellow tube sponges (Aplysina fistularis) than on small yellow sponges or brown tube sponges (Agelas conifera). An experiment seeding settlers onto multiple species and sizes of sponge habitat revealed that settlers persist longer on large yellow sponges than on small yellow sponges or brown sponges. Habitat preference experiments also indicated that settlers prefer large yellow sponges over small yellow sponges or brown sponges. Settlers achieved these preference behaviors using visual, but not chemical, cues. Finally, new settlers arriving from the water column were more likely to occur on large yellow sponges than on small yellow sponges or brown sponges, indicating that the observed habitat preferences existed independent of prior experience. These results support the hypothesis that E. lori have evolved behavioral preferences for sponge habitats that will maximize their post-settlement persistence, and that decisions at settlement will shape the population level pattern of settler distribution on coral reefs.

种群生态学（population ecology）的核心研究方向之一，是探明何种因素能够解释生物类群在其分布范围内的分布格局与种群丰度。这一问题在海洋生态系统中尤为关键：诸多海洋生物会产生扩散性幼体，这些幼体在远海完成发育后，会返回定居于底栖生境（benthic habitat）之中。本研究针对霓虹虾虎鱼（Elacatinus lori）在海绵生境中的分布格局展开调查，并评估不同海绵类型间，新近定居个体（即定居幼体，settlers）的存留率差异是否会催生生境偏好，进而塑造其观测到的分布模式。研究结果显示，相较于小型黄色海绵或棕色管状海绵（Agelas conifera），E. lori定居幼体更常出现在大黄色管状海绵（Aplysina fistularis）之上。将定居幼体接种至不同物种、不同尺寸海绵生境的实验表明，定居幼体在大黄色管状海绵上的存留时长显著长于小型黄色海绵与棕色海绵。生境偏好实验同样证实，定居幼体相较于小型黄色海绵与棕色海绵，更偏好大黄色管状海绵。定居幼体通过视觉而非化学线索（chemical cues）实现此类偏好性行为。最后，从水层（water column）中沉降的新生定居幼体，同样更常出现在大黄色管状海绵之上，这表明观测到的生境偏好并非依赖于过往经验。上述结果验证了相关假说：E. lori已经演化出针对海绵生境的行为偏好，该偏好能够最大化其定居后的存留率；而定居阶段的选择决策，将塑造珊瑚礁（coral reefs）上定居幼体分布的种群级格局。