NEFSC North Atlantic Marine Mammal and Turtle Aerial Abundance Survey 2007

Original provider:
NOAA Northeast Fisheries Science Center (NEFSC)

Dataset credits:
NOAA Northeast Fisheries Science Center (NEFSC)

Abstract:
During 30 July to 29 August 2007, the Northeast Fisheries Science Center conducted an abundance survey using an airplane and ship in waters from Cape Hatteras, North Carolina to the Bay of Fundy, from the coast line to beyond the 2000 m depth contour. The shipboard survey (using the R/V Henry Bigelow) was concentrated in the coastal waters in the Gulf of Maine, and the aerial survey (using the NOAA Twin Otter) covered the rest of the area. The aerial results are reported in this document; while the shipboard results are reported in a companion paper. The primary objective for the aerial survey is to determine the spatial distribution and abundance of cetaceans and sea turtles in the study region. The airplane flew at 600 feet above the water surface at about 110 knots and the circle-back (Hiby) data collection methods were used, where circles were performed on groups of cetaceans and turtles that had 5 or less animals per group. There were about 8,900 km of on-effort track lines that were conducted in Beaufort 3 or less and will be used in the abundance estimates. On these track lines, there were 15 species of identifiable cetaceans, 4 turtle species detected. There were 98 circle-backs performed on 20 species/species groups that can be used to estimate g(0) for these species. The abundance estimates using these data are underway.

原始提供方：美国国家海洋和大气管理局东北渔业科学中心（NOAA Northeast Fisheries Science Center，NEFSC）
数据集来源：美国国家海洋和大气管理局东北渔业科学中心（NOAA Northeast Fisheries Science Center，NEFSC）
摘要：2007年7月30日至8月29日，美国国家海洋和大气管理局东北渔业科学中心开展了一项种群丰度调查，调查范围覆盖北卡罗来纳州哈特拉斯角至芬迪湾的海域，从近岸直至2000米等深线以外区域，调查手段涵盖航空与船舶两种方式。其中船舶调查依托“亨利·比奇洛号”研究船（R/V Henry Bigelow）开展，重点覆盖缅因湾近海水域；航空调查则由NOAA双水獭型飞机（NOAA Twin Otter）执行，覆盖剩余调查区域。本文件仅汇报本次航空调查的结果，船舶调查结果将在配套学术论文中发布。本次航空调查的核心目标为明确研究区域内鲸类（cetaceans）与海龟的空间分布特征及种群丰度。调查飞机以约110节的航速在水面上方600英尺高度飞行，并采用了回转追踪（Hiby）数据采集方法：针对单群个体数不超过5头（只）的鲸类与海龟群体实施回转观测。本次有效调查航线总长约8900千米，所有航线均在蒲福风级3级及以下的海况下开展，相关数据将用于种群丰度估算。在上述有效航线上，共观测到15种可识别鲸类以及4种海龟。此外，针对20个物种类群开展了98次回转观测，可用于估算这些物种的有效探测概率g(0)。基于本次调查数据的种群丰度估算工作目前正在进行中。