Synthesizing mechanisms of density dependence in reef fishes: behavior, habitat configuration, and observational scale.
Synthesizing mechanisms of density dependence in reef fishes: behavior, habitat configuration, and observational scale.
复制标题
珊瑚礁鱼类密度依赖性的综合机制：行为、栖息地配置和观测规模。
DOI：
10.1890/09-0298.1
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发表时间：
2010
期刊：
影响因子：
4.8
通讯作者：
S. Sandin
中科院分区：
文献类型：
--
作者：
J. White;J. Samhouri;A. Stier;Clare L. Wormald;S. Hamilton;S. Sandin
珊瑚和岩礁鱼类种群被广泛用作密度依赖性生命率实验探索的模型系统，但这些系统中密度依赖性死亡率的模式尚未完全了解。特别是，强直接密度依赖性（DDD）定居后死亡率的范式与最近的反密度依赖性（IDD）死亡率的证据形成鲜明对比。我们回顾了导致珊瑚礁鱼类 DDD 和 IDD 人均死亡率的过程，并指出观察到的模式取决于捕食者和猎物的行为、珊瑚礁栖息地的空间配置以及观察的时空尺度。具体来说，捕食者倾向于在其觅食的特征空间尺度上产生 DDD 猎物死亡率，但由于攻击抑制效应（例如风险稀释），猎物死亡率在较小的空间尺度上是 IDD 。因此，在斑块珊瑚礁上，DDD 死亡率可能比 IDD 死亡率更常见，后者往往将捕食者的觅食限制在与猎物聚集相同的规模，从而消除了攻击减少效应。此外，连续珊瑚礁上的相邻猎物群体可能会共享一部分避难所，相对于斑块珊瑚礁上的猎物而言，增加了人均避难所的可用性并降低了 DDD 死亡率，其中斑块边缘可能会阻止这种避难所共享。这些假设形成了一个综合框架来预测各种情况下的预期死亡率模式。对于非社会性、非聚集性物种和为了利用空间聚集的避难所而聚集的物种，IDD 死亡率是可能的，但很可能被 DDD 避难所竞争所取代，特别是在斑礁上。相比之下，对于社会聚集的物种，死亡率在个体聚集规模上应该是 IDD，但在更大的规模上应该是 DDD。几乎所有先前的珊瑚礁鱼类研究的结果都符合这个框架，尽管需要额外的工作来测试许多预测的结果。这种综合调和了最近的珊瑚鱼文献中的一些明显矛盾，并表明在任何研究系统中考虑捕食者和猎物行为的尺度敏感细节的重要性。
Coral and rocky reef fish populations are widely used as model systems for the experimental exploration of density-dependent vital rates, but patterns of density-dependent mortality in these systems are not yet fully understood. In particular, the paradigm for strong, directly density-dependent (DDD) postsettlement mortality stands in contrast to recent evidence for inversely density-dependent (IDD) mortality. We review the processes responsible for DDD and IDD per capita mortality in reef fishes, noting that the pattern observed depends on predator and prey behavior, the spatial configuration of the reef habitat, and the spatial and temporal scales of observation. Specifically, predators tend to produce DDD prey mortality at their characteristic spatial scale of foraging, but prey mortality is IDD at smaller spatial scales due to attack-abatement effects (e.g., risk dilution). As a result, DDD mortality may be more common than IDD mortality on patch reefs, which tend to constrain predator foraging to the same scale as prey aggregation, eliminating attack-abatement effects. Additionally, adjacent groups of prey on continuous reefs may share a subset of refuges, increasing per capita refuge availability and relaxing DDD mortality relative to prey on patch reefs, where the patch edge could prevent such refuge sharing. These hypotheses lead to a synthetic framework to predict expected mortality patterns for a variety of scenarios. For nonsocial, nonaggregating species and species that aggregate in order to take advantage of spatially clumped refuges, IDD mortality is possible but likely superseded by DDD refuge competition, especially on patch reefs. By contrast, for species that aggregate socially, mortality should be IDD at the scale of individual aggregations but DDD at larger scales. The results of nearly all prior reef fish studies fit within this framework, although additional work is needed to test many of the predicted outcomes. This synthesis reconciles some apparent contradictions in the recent reef fish literature and suggests the importance of accounting for the scale-sensitive details of predator and prey behavior in any study system.