School of Biological Sciences, University of Wollongong, Northfields Avenue, Wollongong, New South Wales 2522 Australia.
Ecology. 2011 Mar;92(3):777-83. doi: 10.1890/10-1471.1.
Climate change can move the spatial location of resources critical for population viability, and a species' resilience to such changes will depend upon its ability to flexibly shift its activities away from no-longer-suitable sites to exploit new opportunities. Intuition suggests that vagile predators should be able to track spatial shifts in prey availability, but our data on water pythons (Liasisfuscus) in tropical Australia suggest a less encouraging scenario. These pythons undergo regular long-range (to >10 kmin) seasonal migrations to follow flooding-induced migrations by their prey (native dusky rats, Rattus colletti). However, when an extreme flooding event virtually eliminated rats for a three-year period, the local pythons did not disperse despite the presence of abundant rats only 8 km away; instead, many pythons starved to death. This inflexibility suggests that some vagile species that track seasonally migrating prey may do so by responding to habitat attributes that have consistently predicted prey availability over evolutionary time, rather than reacting to proximate cues that signal the presence of prey per se. A species' vulnerability to climate change will be increased by an inability to shift its activities away from historical sites toward newly favorable areas.
气候变化可能会改变对人口生存至关重要的资源的空间位置，而物种对这些变化的适应能力将取决于其灵活地将活动从不再适宜的地点转移到利用新机会的能力。直觉上认为，行动敏捷的捕食者应该能够追踪猎物可获得性的空间变化，但我们在澳大利亚热带地区的水蟒（Liasis fuscus）的数据表明，情况并不那么乐观。这些蟒蛇会定期进行长途（超过 10 公里）季节性迁徙，以跟随其猎物（本地暗褐家鼠，Rattus colletti）因洪水引发的迁徙。然而，当一场极端的洪水事件几乎使老鼠灭绝了三年时，尽管 8 公里外有大量的老鼠，但当地的蟒蛇并没有扩散；相反，许多蟒蛇饿死了。这种不灵活性表明，一些追踪季节性迁徙猎物的行动敏捷的物种可能通过响应在进化时间内一直预测猎物可获得性的栖息地属性来追踪猎物，而不是对本身表示猎物存在的近因线索做出反应。物种无法将其活动从历史地点转移到新的有利地区，将增加其对气候变化的脆弱性。
