Functional response database from Predator type influences the frequency of functional responses to prey in marine habitats

The functional response of a consumer to a gradient of resource density is a widespread and consistent framework used to quantify the importance of consumption to population dynamics and stability. Within benthic marine ecosystems, both crustaceans and fishes can provide strong top-down pressure on prey populations. Taxon-specific differences in biomechanics or habitat use, among other factors, may lead to variable functional response forms or parameter values (attack rate, handling time). Based on a review of 189 individual functional response fits, we find that these predator guilds differ in their frequency distribution of functional response types, with crustaceans exhibiting nearly double the proportion of sigmoidal, density-dependent functional responses (Holling type III) as predatory fishes. The implications of this finding for prey population stability are significant because type III responses allow for prey persistence while type II responses are de-stabilizing and can lead to extinction. Comparing per capita predation rates across diverse taxa can provide integrative insights into predatory effects and the ability of predation to drive community structure.

消费者对资源密度梯度的功能响应（functional response）是一套被广泛应用且统一的研究框架，用于量化取食作用对种群动态与稳定性的重要性。在底栖海洋生态系统（benthic marine ecosystems）中，甲壳类与掠食性鱼类均可对猎种种群施加显著的自上而下调控压力。除其他因素外，不同分类群在生物力学或生境利用方面的特异性差异，可能导致功能响应的形式或参数（攻击率、处理时间）存在差异。基于对189组独立功能响应拟合结果的综述分析，本研究发现两类捕食类群的功能响应类型频率分布存在显著差异：甲壳类呈现的西格莫伊德型密度依赖功能响应（霍林III型，Holling type III）占比近乎是掠食性鱼类的两倍。该发现对猎种种群稳定性具有重要意义：霍林III型响应可维持猎种种群存续，而霍林II型（Holling type II）响应则会破坏系统稳定性，甚至可能引发猎种种群灭绝。对不同分类群的单位捕食率进行比较，可综合揭示捕食作用的生态效应及其驱动群落结构构建的能力。