A trait-based framework for understanding predator-prey relationships: trait matching between a specialist snake and its insect prey

1. High-quality information on predator-prey relationships is fundamental in understanding food webs, community assembly and ecosystem functioning. Recent analytical advances have made it possible to develop new trait-based approaches to study trophic relationships and evaluate trait-matching between predators and prey. 2. Here we develop a novel analytical approach based on generalized linear mixed-effects models (GLMM) to test the importance of prey availability and to identify the set of prey traits that best explain the occurrence and number of prey in the predator’s diet.
3. We demonstrate the approach by using an extensive dataset on prey availability, prey traits, and gut content collected in all known populations of Vipera graeca, a little-known, endangered snake of alpine grasslands in the Pindos Mountains of the Balkan Peninsula.4. We show that V. graeca is a unique, venomous snake specialised on bush-crickets and grasshoppers (Orthoptera). Prey selection GLMMs showed that th...

1. 捕食者-猎物关系（predator-prey relationships）的高质量信息对于理解食物网（food webs）、群落组装（community assembly）及生态系统功能（ecosystem functioning）至关重要。近期分析技术的进步使得开发基于性状的方法（trait-based approaches）成为可能，这些方法可用于研究营养关系（trophic relationships）并评估捕食者与猎物之间的性状匹配（trait-matching）。
2. 在此，我们开发了一种基于广义线性混合效应模型（generalized linear mixed-effects models, GLMM）的新型分析方法，以检验猎物可获得性的重要性，并识别最能解释捕食者食谱中猎物出现与否及数量的猎物性状集合。
3. 我们通过使用一个广泛的数据集来展示该方法，该数据集包含猎物可获得性、猎物性状及肠道内容物（gut content）信息，收集自希腊蝰蛇（Vipera graeca）所有已知种群——这是一种生活在巴尔干半岛品都斯山脉高山草原中的鲜为人知的濒危蛇类。
4. 我们发现希腊蝰蛇是一种独特的有毒蛇类，专门以灌木蟋蟀和蚱蜢（直翅目，Orthoptera）为食。猎物选择的广义线性混合效应模型显示，th...