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  • Print publication year: 2006
  • Online publication date: November 2009

14 - The future role of large carnivores in terrestrial trophic interactions: the northern temperate view

Summary

… I have lived to see state after state extirpate its wolves. I have watched the face of many new wolfless mountains, and seen the south‐facing slopes wrinkle with a maze of new deer trails. I have seen every edible bush and seedling browsed, first to anemic desuetude, and then to death … I now suspect that just as a deer herd lives in mortal fear of its wolves, so does a mountain live in mortal fear of its deer.

Aldo Leopold 1949.

INTRODUCTION

Central to any treatment of factors affecting the ecological role of large herbivores is a discussion about the factors influencing large herbivore population size and dynamics, and whether they are most influenced by top‐down, or bottom‐up, processes (Pace et al. 1999). The role of resource limitation (a bottom‐up process) in herbivore dynamics is well‐documented from many studies throughout the temperate zone (e.g. Fowler 1987, Gaillard et al. 2000). In contrast, the extent to which predation (a top‐down process) influences herbivore dynamics is less clear, at least in part due to the fact that many of the most detailed long‐term studies of herbivore population dynamics have been conducted in predator‐free environments. The conceptual elegance of strong top‐down effects on herbivores is clear in prosaic statements like Leopold's in the opening quotation, although the absence, or redundancy, of this effect has lain behind the philosophical adoption of the ‘natural regulation’ doctrine in US national parks.

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