Reduced density of the herbivorous urchin Diadema antillarum inside a Caribbean marine reserve linked to increased predation pressure by fishes
Reduced density of the herbivorous urchin Diadema antillarum inside a Caribbean marine reserve linked to increased predation pressure by fishes
复制标题
DOI：
10.1007/s00338-009-0516-6
复制
发表时间：
2009-09-01
期刊：
影响因子：
3.5
通讯作者：
Mumby, P. J.
中科院分区：
文献类型：
--
作者：
Harborne, A. R.;Renaud, P. G.;Mumby, P. J.
疾病大大减少了食草海胆迪亚德马antillarum菲利普在加勒比海珊瑚礁的人口，有助于增加丰富的大型藻类和减少珊瑚覆盖。因此，D.羚羊种群至关重要，但许多珊瑚礁的密度仍然很低。在许多潜在的因素限制这些密度，本研究的重点是捕食压力的鱼类。海洋保护区提供了研究捕食者-猎物相互作用的大规模操纵的机会，因此，D。在巴哈马群岛（Exuma Cays Land and Sea Park; ECLSP）的一个保护区内和保护区外比较了antillarum密度。在ECLSP内外的9个地点对海胆和它们的鱼类捕食者进行了调查。由于较低的捕捞努力，海胆捕食者的总生物量，加权海胆的饮食偏好，是显着较高的ECLSP内。此外，由于大多数物种的生物量增加，公园内的鱼类群落结构有很大不同。在ECLSP内没有看到海胆，这明显低于公园外的0.04海胆密度。回归分析表明，海胆捕食者的生物量和含有海胆的断面的比例之间的关系是非线性的，这表明鱼类生物量的小幅增加显着降低海胆丰度。较低密度的海胆和较高密度的捕食者内的ECLSP之间的联系得到加强折扣五个替代的主要机制（大型藻类覆盖的变化，幼虫供应，环境设置，其他海胆物种的密度和丰富的捕食者没有调查）。加勒比海海洋保护区具有重要的保护作用，但鱼类捕食的增加似乎降低了D。安替拉鲁姆海胆目前对巴哈马珊瑚礁的功能意义有限，但任何未来的恢复D。Antillarum的保护区可能有限，具有潜在的重要生态后果。
Disease has dramatically reduced populations of the herbivorous urchin Diadema antillarum Philippi on Caribbean reefs, contributing to an increased abundance of macroalgae and reduction of coral cover. Therefore, recovery of D. antillarum populations is critically important, but densities are still low on many reefs. Among the many potential factors limiting these densities, the focus of this study is on predation pressure by fishes. Marine reserves provide opportunities to examine large-scale manipulations of predator-prey interactions and, therefore, D. antillarum densities were compared inside and outside a reserve in The Bahamas (Exuma Cays Land and Sea Park; ECLSP). Urchins and their fish predators were surveyed at nine sites inside and outside the ECLSP. Because of lower fishing effort, the total biomass of urchin predators, weighted by their dietary preferences for urchins, was significantly higher inside the ECLSP. Furthermore, fish community structure was significantly different inside the Park because of the increased biomass of the majority of species. No urchins were seen inside the ECLSP and this was significantly lower than the density of 0.04 urchin m(-2) outside the Park. Regression analysis indicated that the relationship between the biomass of urchin predators and the proportion of transects containing urchins was non-linear, suggesting that small increases in fish biomass dramatically reduce urchin abundances. The link between lower density of urchins and higher density of their predators inside the ECLSP is strengthened by discounting five alternative primary mechanisms (variations in macroalgal cover, larval supply, environmental setting, density of other urchin species and abundance of predators not surveyed). Caribbean marine reserves have an important conservation role, but increased fish predation appears to reduce densities of D. antillarum. Urchins currently have limited functional significance on Bahamian reefs, but any future recovery of D. antillarum is likely to be limited in reserves, with potentially important ecological consequences.