Monson D H, Doak D F, Ballachey B E, Johnson A, Bodkin J L
United States Geological Survey, Alaska Biological Science Center, 1011 East Tudor Road, Anchorage, AK 99503, USA.
Proc Natl Acad Sci U S A. 2000 Jun 6;97(12):6562-7. doi: 10.1073/pnas.120163397.
We use age distributions of sea otters (Enhydra lutris) found dead on beaches of western Prince William Sound, Alaska, between 1976 and 1998 in conjunction with time-varying demographic models to test for lingering effects from the 1989 Exxon Valdez oil spill. Our results show that sea otters in this area had decreased survival rates in the years following the spill and that the effects of the spill on annual survival increased rather than dissipated for older animals. Otters born after the 1989 spill were affected less than those alive in March 1989, but do show continuing negative effects through 1998. Population-wide effects of the spill appear to have slowly dissipated through time, due largely to the loss of cohorts alive during the spill. Our results demonstrate that the difficult-to-detect long-term impacts of environmental disasters may still be highly significant and can be rigorously analyzed by using a combination of population data, modeling techniques, and statistical analyses.
我们利用1976年至1998年间在阿拉斯加威廉王子湾西部海滩上发现死亡的海獭（Enhydra lutris）的年龄分布，结合随时间变化的人口统计学模型，来测试1989年埃克森·瓦尔迪兹号油轮泄漏事件的长期影响。我们的结果表明，该地区的海獭在泄漏事件后的几年里存活率下降，而且泄漏事件对年长动物年存活率的影响有所增加而非消散。1989年泄漏事件之后出生的海獭受到的影响小于1989年3月时存活的海獭，但到1998年仍显示出持续的负面影响。泄漏事件对整个种群的影响似乎随着时间的推移而逐渐消散，这主要是由于泄漏期间存活的同龄群体数量减少。我们的结果表明，环境灾难难以察觉的长期影响可能仍然非常显著，并且可以通过结合种群数据、建模技术和统计分析进行严格分析。
