Crayfish and octopus surveys, Ningaloo Reef, Western Australia (WAMSI Node 3 Project 3.1.3)

A series of field trips were made along the entire length of Ningaloo Marine Park (NMP) in May, July, and September 2008. Underwater visual census (UVC) at inner and outer reef sites within both recreational and sanctuary zones (SZ) were undertaken from North West Cape SZ to the Turtle SZ at the southern end of NMP. In total, 132 lobsters from five species were counted from 265 transects and 18 separate locations (58 sites) along the entire coast of the NMP.Sub-tidal surveys on snorkel and SCUBA were used for octopus surveys and were done simultaneously with lobster surveys. In addition to these, inter-tidal surveys were conducted in December 2008 providing total coverage of octopus habitat across a reef profile. In total, just 28 octopus from a single species (Octopus cyanea) were counted from 410 transects (265 subtidal and 145 inter-tidal) and 59 separate sites along the entire coast of the NMP. The specific objectives of this project were:1) A report on stock status for targeted invertebrate species along the length of Ningaloo Marine Park including octopus and lobster.2) A characterization of habitats associated with high numbers of targeted species.3) A comparison of stock abundance in relation to differing levels of visitor access.In addition, a further 6 related questions had been put forward as important to the management of the NMP:1) What is the species diversity of invertebrates at representative habitats in the NMP?2) What is the relative abundance of these species and how do they compare with the 'natural' abundance of these species on comparable reefs?3) How does the abundance of these species change over a gradient of historical and human pressure?4) Are current fishing regulations appropriate?5) What should management targets be?6) What species should be monitored regarding these species?

2008年5月、7月及9月，研究团队沿宁格罗海洋公园（Ningaloo Marine Park, NMP）全岸线开展了一系列野外考察。在休闲区与保护区（Sanctuary Zone, SZ）的内礁及外礁点位，研究人员开展了水下视觉普查（Underwater Visual Census, UVC），调查范围覆盖从西北角保护区至宁格罗海洋公园南端的海龟保护区。本次调查共计在265条样带、18个独立区域（涵盖58个调查点位）的宁格罗海洋公园全岸线范围内，记录到5个物种的龙虾共计132只。

研究团队采用浮潜与水肺潜水开展潮下带调查以进行章鱼种群监测，并将该调查与龙虾调查同步开展。此外，为实现礁体剖面内章鱼栖息地的全面覆盖，研究人员于2008年12月额外开展了潮间带调查。最终在宁格罗海洋公园全岸线的59个独立点位、410条样带（其中潮下带265条、潮间带145条）中，仅记录到单一种类（Octopus cyanea）的章鱼共计28只。

本项目的具体目标如下：
1. 针对宁格罗海洋公园全岸线的目标无脊椎动物物种（包含章鱼与龙虾），提交一份种群现状报告；
2. 对与目标物种高密度分布相关的栖息地进行特征描述；
3. 对比不同游客访问强度下的种群丰度差异。

此外，另有6个与宁格罗海洋公园管理密切相关的重要附加问题被提出：
1. 宁格罗海洋公园典型栖息地内的无脊椎动物物种多样性如何？
2. 这些物种的相对丰度是多少？与同类礁体上该类物种的"自然"丰度相比情况如何？
3. 随着历史与人类压力梯度的变化，这些物种的丰度会发生何种变化？
4. 当前的捕捞法规是否合理？
5. 管理目标应当设定为何？
6. 针对上述物种，应当监测哪些物种？