Species point records from 1990 UMBSM Loch Gairloch and Loch Ewe survey

Loch Gairloch and Loch Ewe lie on the north-west Scottish mainland in an area of Torridonian sandstone. They were surveyed during 1990 as part of the survey of Scottish sealochs. Although adjacent, the two lochs are very different in character. Loch Ewe is a north-facing fiord with two main sills and basins, a maximum depth of 73 m and is mostly sheltered from wave action. Loch Gairloch faces west, has no sills and is exposed over much of its length. It has depths of over 100 m at its entrance and appears to have more open coast affinities than Loch Ewe with warmer, clearer water. Tidal streams are negligible in both lochs. The lochs have extensive sandy beaches and hold a wide range of sublittoral sediments which, although predominantly coarse, grade to soft mud. Hard substrata were common in shallow water in both lochs but limited in deeper water. The lochs are situated in a popular holiday area with the Inverewe gardens one of the major attractions. There is a large caravan site on Loch Gairloch and numerous holiday apartments. There are small sewage outfalls around both lochs, a NATO refuelling jetty in Loch Ewe and a fishing harbour in Loch Gairloch. Both lochs have mussel farms and Loch Ewe also has salmon cages. There are two SSSI's in the areas, one of which borders the head of Loch Gairloch. There has been a great deal of marine research carried out in the area, and particularly Loch Ewe, on account of the SOAFD (formerly DAFS) laboratory at Firemore Bay. Of note was a Phase 1 diving survey carried out in 1989 by a Seasearch team (Gubbay 1990). Ninety-seven sites were surveyed which included 69 diving sites, 13 dregde samples, 10 suction samples and 11 littoral surveys; 32 habitat/community types are described. Both lochs could be divided into inner, central and outer zones with cape Laminaria saccharina forest in the inner, mixed kelp forest in the cental and Laminaria hyperborea forest in the outer zone. Although some sites were grazed by sea urchins, at many there was a luxuriant understorey flora often dominated by filamentous brown algae. Circalittoral bedrock and boulders were more limited in extent. In the outer lochs, these held ascidians and hydroids to a depth of 24 m. The brachiopod Neocrania anomala was found on deeper and more sheltered boulders. Deep, sheltered bedrock with the anemone Protanthea simplex was only found at Resolution Rock in Loch Ewe. The sediments were predominatly sandy and were often very rich, particularly in Loch Gairloch. Waves of coarse, shelly gravel with maerl were found in the outer parts of both lochs. In slightly more sheltered water, there were large expanses of firm, fine sand with species such as the echinoderms Echinocardium cordatum and Labidoplax digitata. In deeper water this merged into sandy mud with seapens. With increasing shelter, the sediments became muddier and more stable, supporting dense algal populations in shallow water. In Loch Shieldaig, the most sheltered basin, very soft mud was covered with a filamentous algal blanket. Soft mud in deeper water held burrowing crustacens such as the prawn Nephrops norvegicus. There was a small bed of eel grass Zostera marina at the entrance to Loch Gairloch and maerl with the flame shell Limaria hians was found at the head of Loch Ewe. Littoral communities were less varied with the majority of shores consisting of moderately exposed bedrock and boulders and numerous fine sandy beaches. Sheltered shores dominated by Ascophyllum nodosum were restricted to the heads of lochs, where the free-living growth form A. nodosum f. mackaii was also found. Nine habitat/community types and 22 species have been provisionally assessed to be of Loch or Regional nature conservation importance. Records currently considered sensitive have been removed from this dataset.盖尔洛赫湾（Loch Gairloch）与埃韦湾（Loch Ewe）坐落于苏格兰西北大陆的托里登砂岩（Torridonian sandstone）分布区，二者于1990年作为苏格兰滨海海湾（sealochs）系统性调查的组成部分完成勘测。尽管地理位置毗邻，两处海湾的生态与地貌特征却存在显著差异。 埃韦湾为朝北朝向的峡湾（fiord），拥有两处主海槛（sill）与盆地结构，最大水深达73米，整体受波浪作用影响较弱，遮蔽性良好。盖尔洛赫湾朝向正西，无海槛分布，其大部分岸线暴露于外海波浪中；湾口处水深超过100米，相较于埃韦湾更具开放海岸属性，水体温度更高、透明度更佳。两处海湾的潮流均极微弱。 两处海湾均分布有广阔的沙质海滩，且涵盖多样的潮下带沉积物（sublittoral sediments）：沉积物以粗粒组分为主，逐渐过渡为软泥质。浅水区广泛分布硬质底质（substrata），但深水区硬质底质较为稀少。 该区域为热门度假胜地，因弗维花园（Inverewe gardens）是核心景点之一。盖尔洛赫湾沿岸设有大型房车营地（caravan site）与大量度假公寓；两处海湾周边均设有小型污水排放口（sewage outfall），埃韦湾内建有北大西洋公约组织（NATO）加油码头，盖尔洛赫湾则设有渔港（fishing harbour）。两处海湾均开展贻贝养殖（mussel farm），埃韦湾另设有三文鱼网箱养殖区（salmon cage）。区域内设有两处具特殊科学价值地点（SSSI, Site of Special Scientific Interest），其中一处毗邻盖尔洛赫湾湾顶。 得益于法尔莫尔湾（Firemore Bay）的苏格兰农业、渔业与食品发展局（SOAFD，前身为DAFS）实验室，该区域尤其是埃韦湾开展了大量海洋科学研究，其中1989年由海洋搜索勘测团队（Seasearch team）完成的第一阶段潜水勘测（Phase 1 diving survey，Gubbay 1990）尤为值得关注：此次勘测共覆盖97处采样点，包括69处潜水勘测点、13次拖网采样（dredge samples）、10次抽吸采样（suction samples）及11次潮间带勘测（littoral surveys），共描述了32种生境/群落类型（habitat/community types）。 两处海湾均可划分为内湾、中湾与外湾三个区域：内湾的岬角区域分布有糖海带（Laminaria saccharina）林，中湾为混合海带林，外湾则以掌状海带（Laminaria hyperborea）林为主。尽管部分区域存在海胆（sea urchin）啃食现象，但多数区域仍拥有繁茂的下层植被群落，优势类群多为丝状褐藻（filamentous brown algae）。周潮下带（circalittoral）硬质基岩与巨砾（boulder）分布范围有限，在外湾区域，此类底质在24米水深范围内均有被囊动物（ascidian）与水螅虫（hydroid）附着。异常新颅贝（Neocrania anomala，brachiopod）见于更深且遮蔽性更强的巨砾之上。仅在埃韦湾的决议岩（Resolution Rock）处，发现了生长有简单原花海葵（Protanthea simplex，anemone）的深水区遮蔽基岩。 沉积物以沙质为主，且通常有机质含量极高，盖尔洛赫湾尤为显著。两处海湾的外湾区域均分布有覆盖珊瑚藻砂（maerl）的粗粒贝壳砾石（shelly gravel）滩。在遮蔽性稍强的水域，分布有大片坚实细沙底质，栖息有棘皮动物（echinoderms）如心形海胆（Echinocardium cordatum）与指形拉氏钩虾（Labidoplax digitata）；深水区则过渡为含海笔（seapen）的沙质泥底。随着遮蔽性提升，沉积物逐渐变为更稳定的软泥质，浅水区可支撑茂密的藻类种群。在遮蔽性最强的希尔迪格湾（Loch Shieldaig）盆地中，极软的泥质底质被丝状藻类覆盖层所覆盖。深水区的软泥底质中栖息有穴居甲壳动物（crustaceans），如挪威龙虾（Nephrops norvegicus）。盖尔洛赫湾湾口分布有小片大叶藻（Zostera marina，鳗草）床，埃韦湾湾顶则发现了附着有焰壳银蛤（Limaria hians）的珊瑚藻砂群落。 潮间带群落多样性相对较低，多数岸线为中等暴露程度的基岩与巨砾滩，同时分布有大量细沙海滩。以墨角藻（Ascophyllum nodosum）为优势种的遮蔽型岸线仅分布于海湾顶部，此处同时发现了墨角藻的自由生长变种——麦克墨角藻（A. nodosum f. mackaii）。目前已有9种生境/群落类型与22个物种被初步评估为具有海湾级或区域级自然保护价值。本数据集已移除当前认定为敏感的观测记录。