Prince William Sound Marine Bird Surveys, July 2012 to 2018, Gulf Watch Alaska Pelagic Component

These data are part of the Gulf Watch Alaska (GWA), Pelagic Component of the Exxon Valdez Oil Spill Trustee Council. Gulf Watch Alaska is the long-term ecosystem monitoring program of the Exxon Valdez Oil Spill Trustee Council for the marine ecosystem affected by the 1989 oil spill. In this study, small boat surveys were conducted to estimate marine bird and sea otter populations in Prince William Sound (PWS), Alaska during July (“summer”) 2012-2018, using methods developed in 1989-91 (Klosiewski and Laing 1994). These surveys were a continuation of surveys conducted to examine trends of marine birds in the oiled and unoiled areas of PWS during March ("winter") and July ("summer"), 1989 to 2010. Surveys were conducted in three strata every other year during the month of July. Three fiberglass boats traveling at low speeds (6-12 mph) were used to survey the area over a three-week period. Two observers and a boat operator recorded all marine birds and marine mammals within the transect “window”(100 m either side of the boat). The dataset is several comma separated files exported from the marine bird and mammal observation software dLOG (Ford 1999). The data contained in the files named Survey_Sighting are the observations of species, numbers, and behavior recorded by observers during surveys. The data contained in the files named Survey_Header are the weather and environmental observations that were made during surveys.

本数据集隶属于阿拉斯加海湾观察项目（Gulf Watch Alaska, GWA），属于埃克森瓦尔迪兹漏油事件信托委员会（Exxon Valdez Oil Spill Trustee Council）的远海组分。阿拉斯加海湾观察项目是埃克森瓦尔迪兹漏油事件信托委员会针对1989年漏油事件影响的海洋生态系统所设立的长期生态监测计划。本研究于2012至2018年的7月（"夏季"），采用1989-1991年开发的调查方法（Klosiewski与Laing，1994），在阿拉斯加威廉王子湾（Prince William Sound, PWS）开展小船调查以估算海鸟与海獭种群数量。本次调查是1989至2010年3月（"冬季"）与7月（"夏季"）期间，针对威廉王子湾受漏油与未受漏油区域海鸟种群趋势开展的调查的延续。调查以每两年一次的频次，于每年7月在三个抽样分层内开展，由3艘以低速（6-12英里/小时）航行的玻璃钢船在三周周期内完成区域踏勘。两名观察员与一名船载操作员记录下样带"视野窗口"（船体两侧各100米范围内）内的所有海鸟与海洋哺乳动物。本数据集由海鸟与海洋哺乳动物观测软件dLOG（Ford，1999）导出的多个逗号分隔文件组成。其中名为Survey_Sighting的文件存储了观察员在调查期间记录的物种、个体数量与行为观测数据；名为Survey_Header的文件存储了调查期间获取的气象与环境观测数据。