Bailey Helen, Secor David H
Chesapeake Biological Laboratory, University of Maryland Center for Environmental Science, P.O. Box 38, Solomons, MD 20688, USA.
Sci Rep. 2016 Jul 26;6:30280. doi: 10.1038/srep30280.
An increase in the intensity and frequency of extreme events is predicted to occur as a result of climate change. In coastal ecosystems, hurricanes and flooding can cause dramatic changes in water quality resulting in large mortality events in estuarine fauna. Facultative migration behaviors represent a key adaptation by which animals can evacuate ecological catastrophes, but remain poorly studied in marine systems. Here we identify coastal evacuations by otherwise resident riverine striped bass in the Hudson River Estuary, New York, USA, caused by an intense period of tropical storms in autumn 2011. These storms produced record rainfall and high water discharges into the Hudson River Estuary that increased the water level and reduced the water temperature, salinity and dissolved oxygen levels. Striped bass moved out of the estuary, exhibiting novel migration behaviours, that may have been in response to the strong flow and unsuitable conditions. In the months following the storms, some fish demonstrated exploratory trips back to the estuary, which may have been to assess the conditions before returning for the remainder of the winter. Behavioural adaptions to weather events by striped bass and other coastal fishes will depend on maintenance of key population segments and unimpeded evacuation routes.
预计气候变化将导致极端事件的强度和频率增加。在沿海生态系统中，飓风和洪水会引发水质的剧烈变化，导致河口动物大量死亡。兼性迁移行为是动物逃避生态灾难的一种关键适应方式，但在海洋系统中仍研究不足。在此，我们确定了美国纽约哈德逊河河口原本栖息的河条纹鲈因2011年秋季一段强烈的热带风暴而进行的沿海撤离。这些风暴带来了创纪录的降雨，并向哈德逊河河口大量排水，导致水位上升，水温、盐度和溶解氧水平降低。条纹鲈离开了河口，表现出新颖的迁移行为，这可能是对强水流和不适宜条件的反应。在风暴过后的几个月里，一些鱼表现出探索性地返回河口的行为，这可能是为了在返回度过剩余冬季之前评估环境状况。条纹鲈和其他沿海鱼类对天气事件的行为适应将取决于关键种群的维持以及畅通无阻的撤离路线。
