资源环境科技发展态势分析平台

Recently Beschta et al. (2018) published a paper proposing that recovery of aspen in Yellowstone National Park was shaped by multi-scalar trophic cascade reversals driven by the reintroduction of grey wolves. Although this conclusion is one possibility, and might help explain what was observed, the paper of itself provides neither adequate evidence or inference to draw such firm conclusions. Most importantly, the suggested operands driving trophic cascade reversals, i.e. 'human shielding', and consequent altered elk and wolf activity patterns and densities, were unmeasured, and there was no replication in either space or time of those measurements that were made. Ecology and its associated ecosystem management are not well-served by claims about ecological processes and mechanisms that are unsupported by the presented evidence.