2004 Scottish Natural Heritage (SNH) Lochs Duich, Long and Alsh biogenic and rocky reefs survey

Emu Limited (Emu Ltd.) was commissioned by Scottish Natural Heritage (SNH) to carry out fieldwork to initiate the monitoring of the reef features within the Loch Duich, Loch Long and Loch Alsh candidate Special Area of Conservation (cSAC). The purpose of the fieldwork was to establish a series of relocatable survey transects and single point survey stations at locations which reflected the biological and environmental diversity of the rocky and biogenic reef features of the site. The data acquired from each of these survey stations is to be used to assess the âfavourable conditionâ status of the interest features on future monitoring surveys and provide sufficient information from which a judgement on the existing condition of the interest features can be made.
The Lochs Duich, Long and Alsh (DLA) cSAC is designated for the intertidal and subtidal rocky reefs found throughout the site and biogenic reefs formed by dense beds of horse mussel, Modiolus modiolus. Sub-features of interest for which survey effort was targeted were:
Very sheltered, rocky reefs subject to variable salinity (Loch Long);
Deep sublittoral bedrock cliffs supporting communities characterised by the brachiopods Neocrania anomala, Terabratulina retusa and the anemone Protanthea simplex (Loch Duich),
Dense beds of the normally cryptic brittlestar Ophiopholis aculeata (sills within the centre of Loch system); and
Tide-swept bedrock communities (Kyle Rhea).
Where possible, survey stations were placed in the same location as earlier survey visits to the area in order to allow the current condition of the site to be assessed in relation to information on its former condition.
In addition to this, selected elements of a survey carried out by Heriot-Watt University (HWU) in 1999 on the dense aggregations of the horse mussel Modiolus modiolus within Kyle Akin were repeated. The aim was to directly compare the results from the two surveys to enable an assessment to be made on the condition of the M. modiolus bed.
The following is a summary of the survey work carried out:
MNCR phase 2 surveys along 6 transects comprising littoral (by shore worker) and sublittoral (by diver) sections and one sublittoral transect
MNCR phase 2 surveys by diver at 9 spot locations
estimates of frequency of occurence of dominant/characteristic taxa (by use of replicate quadrats) in biotopes of interest at above locations
MNCR phase 2 surveys by ROV along 12 transects
Modiolus bed surveys by ROV at 6 spot locations

Emu Limited（Emu Ltd.）受苏格兰自然遗产（SNH）委托，在洛奇杜伊希、洛奇朗和洛奇阿尔什拟定的特殊保护区（cSAC）内开展实地考察，以启动对该地区礁石特征的监测。实地考察的目的是在反映该地岩石和生物礁特征生物和环境多样性的地点建立一系列可移动的样带和单点调查站。从这些调查站获取的数据将被用于评估未来监测调查中感兴趣特征的“适宜状况”，并提供足够的信息，以便对感兴趣特征的现有状况作出判断。

洛奇杜伊希、洛奇朗和洛奇阿尔什（DLA）cSAC被指定用于保护整个地区的潮间带和潮下带岩石礁以及由密集的海马蛤床（Modiolus modiolus）形成的生物礁。调查重点关注的次级特征包括：

洛奇朗中受盐度变化影响的极为隐蔽的岩石礁；
洛奇杜伊希中支撑着由新棘翼贝（Neocrania anomala）、真珠贝（Terabratulina retusa）和水螅（Protanthea simplex）构成的群落的海底悬崖；
洛奇系统中心峡谷内的密集隐秘海星（Ophiopholis aculeata）床；以及
受潮汐冲刷的岩石群落（凯尔雷厄）。尽可能地将调查站放置在之前对该地区进行的调查的同一位置，以便将当前状况与过去的状况进行比较。

此外，还对1999年由赫里奥特-沃特大学（HWU）在凯尔阿金密集的海马蛤床进行的调查中选定的部分进行了重复。目的是直接比较两次调查的结果，以便对M. modiolus床的状况进行评估。

以下是对所进行的调查工作的总结：
在6个样带上进行的MNCR第2阶段调查，包括沿岸（由岸上工作人员进行）和潮下带（由潜水员进行）部分，以及一个潮下带样带；
在9个地点由潜水员进行的MNCR第2阶段调查；
使用重复样方估算上述地点感兴趣生境中优势/典型群落的频率；
在12个样带上进行的MNCR第2阶段潜水调查；
在6个地点由遥控水下航行器进行的海马蛤床调查。