Historical datasets of dugong (Dugong dugon) observations in the Kimberley region of Western Australia (1985)

<p>This series of surveys represents the first attempt to quantitatively assess dugong distribution and abundance throughout the west Kimberley region. The 1985 survey was divided into two sections - The southern section, which extended from LaGrange Bay to Broome and the northern section, which commenced just north of Broome and extended to Cape Leveque including the Lacepede Islands and into King Sound</p>
<p>For all sections two flights were conducted during each of April, July and October resulting in a total of 12 flights. Each flight within each survey area was replicated, with transects flown perpendicular to the coast at a height of 275m and speed of 90 knots. Distances between transects varied as did the lengths of transects as flights were generally made to a point where visibility restricted the sighting potential. Observations were conducted by a single observer with markers delineating a strip on the water surface equivalent to 400m wide. Flights were conducted during neap tides to maximise sighting potential. Aside from dugong observation other megafauna, such as dolphins and turtles, were also recorded, but for the purposes of this report only dugong sightings are described.</p>
<p>Data and report from https://data.pawsey.org.au/public/?path&#61;/WA%20Node%20Ocean%20Data%20Network/AODN/Dave_Holley_Dugongs (December 2020)</p>

<p>本系列调查旨在首次对西金伯利地区海牛的分布和数量进行定量评估。1985年的调查分为两个部分——南部区域从拉格兰奇湾延伸至布鲁姆，而北部区域则从布鲁姆北部开始，直至利韦克角，包括蕾丝佩德群岛，并深入至金斯顿湾。</p><p>在每年的四月、七月和十月，每个部分均进行了两次飞行调查，共计12次飞行。每个调查区域的每次飞行均进行了重复，以垂直于海岸线，高度为275米，速度为90海里/小时的方式执行横断面飞行。横断面的间距以及长度不尽相同，因为飞行通常在能见度受限、影响观测潜力的地点停止。观测由一名观察者进行，标记在水面上的带状区域宽度相当于400米。为了最大化观测潜力，飞行在低潮期间进行。除了海牛观测外，其他大型海洋生物，如海豚和海龟，也被记录下来，但本报告仅描述海牛的观测情况。</p><p>数据及报告来源：https://data.pawsey.org.au/public/?path=/WA%20Node%20Ocean%20Data%20Network/AODN/Dave_Holley_Dugongs（2020年12月）</p>