Enberg Katja, Fowler Mike S, Ranta Esa
Integrative Ecology Unit, Department of Biological and Environmental Sciences, University of Helsinki, PO Box 65 (Viikinkaari 1), Helsinki, FIN-00014, Finland.
Proc Biol Sci. 2006 Oct 7;273(1600):2491-9. doi: 10.1098/rspb.2006.3611.
Understanding the effects of population management on the community a target species belongs to is of key importance for successful management. It is known that the removal or extinction of a single species in a community may lead to extinctions of other community members. In our study, we assess the impacts of population management on competitive communities, studying the response of both locally stable and unstable communities of varying size (between four and 10 species) to three different management strategies; harvesting of a target species, harvesting with non-targeted catch, and stocking of the target species. We also studied the consequences of selecting target species with different relative abundances, as well as the effects of varying environmental conditions. We show here how the effects of management in competitive communities extend far beyond the target population. A crucial role is played by the underlying stability properties of the community under management. In general, locally unstable communities are more vulnerable to perturbation through management. Furthermore, the community response is shown to be sensitive to the relative density of the target species. Of considerable interest is the result that even a small (2.5%) increase in the population size of the target species through stocking may lead to extinction of other community members. These results emphasize the importance of considering and understanding multi-species interactions in population management.
了解种群管理对目标物种所属群落的影响对于成功管理至关重要。众所周知，群落中单一物种的移除或灭绝可能导致其他群落成员的灭绝。在我们的研究中，我们评估了种群管理对竞争群落的影响，研究了不同规模（4至10个物种）的局部稳定和不稳定群落对三种不同管理策略的反应；目标物种的捕捞、非目标捕捞以及目标物种的放养。我们还研究了选择具有不同相对丰度的目标物种的后果，以及不同环境条件的影响。我们在此展示了竞争群落中管理的影响如何远远超出目标种群。管理下群落的潜在稳定性属性起着关键作用。一般来说，局部不稳定的群落更容易受到管理扰动的影响。此外，群落反应对目标物种的相对密度很敏感。一个相当有趣的结果是，即使通过放养使目标物种的种群数量小幅增加（2.5%）也可能导致其他群落成员灭绝。这些结果强调了在种群管理中考虑和理解多物种相互作用的重要性。
