ABSTRACT

Interactions between species and individuals can determine their survival in the wild. Most of the time these relationships are difficult to study in situ by direct observation. However, technology can help collect these data with minimal impact on animals’ behaviour. Egg stage is certainly the most vulnerable life stage in crocodilians, but few studies have focused on animal species visiting crocodilian nests and associated egg predation. Herein, we use camera-traps in four Mexican states (Chiapas, Oaxaca, Jalisco, Tabasco) to determine vertebrate species and egg predators associated with wild nests of Caiman crocodilus chiapasius, Crocodylus acutus and Crocodylus moreletii. We recorded 72 species of vertebrates at nesting sites and obtained the first photographic evidence of crocodilian egg predation by Caracara cheriway, Cuniculus paca, Didelphis virginiana and Procyon lotor. We also identified commensalism, cooperation, and predation as types of interactions within observed nesting areas, which indicates the importance of crocodilian nesting areas for other wild vertebrates. Finally, we found that crocodilian egg predation depends on species richness present in the area of study, as well as crocodilian size.

摘要

物种与个体之间的相互作用可以决定其在野外的生存。在大多数情况下，很难通过直接观察来就地研究这些关系。但是，技术可以帮助收集这些数据，而对动物的行为影响最小。卵期肯定是鳄鱼生活中最脆弱的生命阶段，但是很少有研究集中在造访鳄鱼巢和相关卵捕食的动物物种上。在这里，我们使用相机陷阱四和墨西哥各州（恰帕斯，瓦哈卡州，哈利斯科州，塔瓦斯科），以确定与野生燕窝相关的脊椎动物物种和蛋大鳄凯门鳄chiapasius，五步蛇鳄和鳄moreletii。我们在巢穴记录了72种脊椎动物，并获得了第一个通过Caracara cheriway，Cuniculus paca，Didelphis virginiana和Procyon lotor捕食鳄鱼卵的摄影证据。我们还确定了共鸣，合作和掠夺是观察到的筑巢区域内相互作用的类型，这表明鳄鱼筑巢区域对其他野生脊椎动物的重要性。最后，我们发现鳄鱼卵的捕食取决于研究区域中物种的丰富程度以及鳄鱼的大小。