Assessment of the effects of the 2004 coral bleaching event at Lihou Reef National Nature Reserve (Coral Sea) using towed video (Towvid)

Reefs in the Lihou Reef National Nature Reserve (NNR) were surveyed between 8-13 October 2004 in order to assess the effects of significant coral bleaching, which was observed during previous surveys in March 2004.A series of six video tows were conducted at depths between 45m and 60m, in the lagoon area of Lihou Reef NNR and also to the north of Anne Cay. A computer-based application, allowing keyboard classification was used to analyse the video tapes. Habitats were classified based on the substrata (3 categories) and overlying epibenthos (6 categories) viewed on the tapes.
Towed underwater video (Towvid) was used to survey previously unsurveyed deeper waters of the Lihou Reef National Nature Reserve (NNR), for the presence of coral communities and to establish the extent of bleaching at depth.
The Lihou Reef National Nature Reserve (NNR) is one of two protected areas in the Coral Sea region. The reserve is located in the Coral Sea 400 kilometres east of Townsville, Queensland. It was proclaimed on the 16th August 1982 under the National Parks and Wildlife Conservation Act 1975.The Coringa-Herald National Nature Reserve and Lihou Reef National Nature Reserve Management Plan states that both reserves are to be managed as strict nature reserves - World Conservation Union (IUCN) Category 1a - strict nature reserve. Such reserves are managed primarily to ensure habitats, ecosystems and native species are preserved in an undisturbed state as well as to facilitate research.

2004年10月8日至13日，调查人员对丽侯礁国家自然保护区（National Nature Reserve，简称NNR）内的珊瑚礁开展调查，以评估2004年3月前期勘测中观测到的大规模珊瑚白化所带来的影响。本次调查在丽侯礁礁湖区域及安妮礁以北海域的45米至60米水深范围内，完成了6次拖曳式视频采样。研究采用支持键盘分类的计算机应用程序对录像带进行分析，根据录像中观测到的底质（共3类）与上层底栖生物（共6类）对生境进行分类。

本次调查还采用拖曳式水下视频（Towvid）技术，对丽侯礁国家自然保护区此前未被勘测的深水区开展勘测，以查明珊瑚群落的存在情况，并明确深层海域珊瑚白化的波及范围。

丽侯礁国家自然保护区是珊瑚海区域仅有的两个保护区之一，坐落于昆士兰州汤斯维尔以东400公里的珊瑚海海域，于1982年8月16日依据《1975年国家公园与野生动物保护法》正式设立。《科林加-赫尔德国家自然保护区与丽侯礁国家自然保护区管理规划》明确规定，两个保护区均按照严格自然保护区的标准进行管理——即世界自然保护联盟（IUCN）1a类严格自然保护区。此类保护区的核心管理目标为确保生境、生态系统及本土物种保持未受干扰的保存状态，同时为科学研究提供便利。