Climate-change impacts on fish and wildlife habitat in coastal wetlands of Georgian Bay

气候变化对乔治亚湾沿海湿地鱼类和野生动物栖息地的影响

• 批准号: 194608-2013
• 负责人: ChowFraser, Patricia
• 金额: $ 1.6万
• 依托单位: McMaster University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=523240
• 关键词: Climate; change; impacts; fish; wildlife

Between May 1998 and January 2000, the water level in Lake Huron dropped a meter from 176.91 m above sea level (asl) to 175.92 m. During the following decade, mean monthly water levels averaged 176.0 m asl, and levels are expected to drop even further by the end of 2012. Such a drop in water levels in the Great Lakes has been predicted by Global Circulation Models as a manifestation of global climate change. The water-level decline has dried up many coastal wetlands in Georgian Bay (eastern arm of Lake Huron), which are known to provide critical habitat for fish and wildlife species. Our research showed that in 7 wetlands, an observed drop of 80 cm over a ten-year period (1999-2009) corresponded to an average of 25% of aquatic habitat being converted to terrestrial habitat. This water-level drop also disconnected a fifth of all wetlands from Georgian Bay, and has prevented seasonal access of migratory fish into spawning and nursery habitat. Besides its impact on migratory fish, loss of wetland habitat may also have a negative effect on semi-aquatic turtles such as the Blanding's turtle, which use coastal wetlands as staging areas to feed prior to their nesting migrations. The primary goal of this proposal is to determine the relationship between fish and wildlife habitat and water level in different regions of Georgian Bay, including a southern site where the low water level is confounded with human development, a northern site that is primarily undisturbed by human activities, and islands with and without coastal wetlands. I will use radio-transmitters to determine the spawning and nursery habitat used by northern pike and muskellunge and a combination of GPS-enabled radio-telemetry and surveillance cameras to determine aquatic and terrestrial habitat used seasonally by the Blanding's turtle. The information will be incorporated into a Geographic Information System and supplemented with bathymetric and contour data to build habitat-suitability models for each species. I will then quantify the amount of critical habitat as a function of different water-level scenarios for representative sites throughout Georgian Bay. A second goal is to understand the impacts of diking as a possible mitigation measure to prevent wetland dessication.

1998年5月至2000年1月，休伦湖的水位从海拔176.91米下降到175.92米。 在接下来的十年中，月平均水位平均为176.0米，预计到2012年底水位将进一步下降。全球环流模型预测，五大湖的水位下降是全球气候变化的表现。水位下降使乔治亚湾（休伦湖的东臂）的许多沿海湿地干涸，这些湿地为鱼类和野生动物提供了重要的栖息地。我们的研究表明，在7个湿地中，在10年期间（1999-2009年）观察到的80厘米的下降相当于平均25%的水生栖息地转化为陆地栖息地。这一水位下降也使格鲁吉亚湾五分之一的湿地与之断开，并阻止了洄游鱼类季节性地进入产卵和育苗生境。除了对洄游鱼类的影响外，湿地栖息地的丧失也可能对半水生海龟产生负面影响，如布兰丁海龟，它们在筑巢迁徙前将沿海湿地作为中转区觅食。本提案的主要目标是确定格鲁吉亚湾不同区域鱼类和野生动物栖息地与水位之间的关系，包括低水位与人类发展相混淆的南部地点，主要不受人类活动干扰的北方地点，以及有和没有沿海湿地的岛屿。我将使用无线电发射机来确定北方梭子鱼和麝香鱼的产卵和育苗栖息地，并结合GPS无线电遥测和监视摄像机来确定布兰丁海龟季节性使用的水生和陆生栖息地。这些信息将被纳入地理信息系统，并补充测深和等高线数据，以建立每个物种的生境适宜性模型。 然后，我将量化的关键栖息地的数量作为不同的水位情景的功能，整个格鲁吉亚湾的代表性网站。第二个目标是了解堤防作为一种可能的缓解措施，以防止湿地干燥的影响。