Predicting how the inducible defences of large mammals to human predation shape spatial food web dynamics

预测大型哺乳动物对人类捕食的诱导防御如何塑造空间食物网动态

• 批准号: EP/Y03614X/1
• 负责人: Robert Montgomery
• 金额: $ 206.67万
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FY03614X%2F1
• 关键词: Predicting; how; inducible; defences; large

Exploring the mechanisms that structure food webs has been a cornerstone of ecological inquiry for over a century. The importance of predator-prey interactions, particularly among large animals near the apex positions of trophic systems, has been highlighted. Predators exert consumptive, also known as lethal, effects (CEs), and nonconsumptive effects (NCEs), represented by the fitness-compromising tradeoff decisions that prey make to avoid predation (i.e., NCEs). The nature and strength of these CEs and NCEs can cascade down trophic systems and drive the evolution of defences in prey induced by predation. Much has been learned from this research effort and yet, two vital knowledge gaps persist, both relating to human predation at the top of food chains. First, it is not known whether large animals have evolved defences that are induced by human predation. This is unclear because the costs of large animal decisions in response to human predation have not yet been properly quantified. Second, the impact of human-induced NCEs on food web dynamics has not been measured. Consequently, it is not known whether human predation exerts effects that can cascade down trophic systems. I will fill these major voids in ecological understanding via experimental study of a Ugandan large mammal system experiencing human predation from subsistence poaching. Dividing my 880 km2 study area into equal-sized treatment (where subsistence poaching is common) and control (where subsistence poaching is naturally rare because of distance from human community) portions, I will quantify the costs of large mammal decisions and fit habitat domain models to elucidate how human predation shapes food web dynamics. While it is widely known that humans have top-down and bottom-up impacts on trophic systems, my project will articulate the ways in which cascading mechanisms can flow from human predation with important implications in the Anthropocene for every other trophic system on earth.

一个多世纪以来，探索食物网的结构机制一直是生态研究的基石。捕食者与猎物相互作用的重要性，特别是在营养系统顶端附近的大型动物中，已经得到强调。捕食者会施加消耗性效应（也称为致死性效应）（CE）和非消耗性效应（NCE），以猎物为避免捕食而做出的损害适应度的权衡决策（即 NCE）为代表。这些CE和NCE的性质和强度可以级联至营养系统并驱动捕食引起的猎物防御的进化。从这项研究工作中我们学到了很多东西，但仍然存在两个重要的知识差距，两者都与食物链顶端的人类捕食有关。首先，尚不清楚大型动物是否进化出了由人类捕食引起的防御能力。目前尚不清楚，因为大型动物应对人类捕食的决策成本尚未得到适当量化。其次，人类引起的非化学实体对食物网动态的影响尚未得到测量。因此，尚不清楚人类的捕食是否会产生级联营养系统的影响。我将通过对乌干达大型哺乳动物系统的实验研究来填补生态理解中的这些主要空白，该系统经历了人类因自给性偷猎而进行的捕食。将我的 880 平方公里研究区域划分为同等大小的处理区（其中生存偷猎很常见）和控制部分（其中由于距人类社区较远，生存偷猎自然很少见）部分，我将量化大型哺乳动物决策的成本并拟合栖息地域模型阐明人类捕食如何塑造食物网动态。虽然众所周知，人类对营养系统有自上而下和自下而上的影响，但我的项目将阐明人类捕食产生的级联机制的方式，对人类世对地球上所​​有其他营养系统产生重要影响。