Ice age Ullapool discovered

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EXPLORATION of the seas around Ullapool has confirmed the presence of some of Scotland’s most important marine wildlife features.

The work builds on previous surveys which showed that the present-day landscape of the region has been strongly shaped by Quaternary glaciation particularly over the past 500,000 years.

During the recent survey, a team of marine biologists from Heriot-Watt University’s School of Life Sciences and Scottish Natural Heritage (SNH) charted the presence, condition and extent of a number of Priority Marine Features (PMFs) in Loch Broom, Little Loch Broom, Loch Gairloch, Loch Ewe, Gruinard Bay and the Summer Isles.

In Little Loch Broom a bed of coral-like algae maerl was identified as one of the richest examples of the habitat in this part of Scotland.

Seagrass beds in Loch Gairloch and Gruinard Bay were more widespread than previously thought, and scientists think the beds are possibly the richest examples in north Scottish waters.

Dense fields of the northern feather star were observed at the mouths of Loch Broom and Little Loch Broom, with a particularly rich and previously unrecorded bed found outside the mouth of Loch Gairloch.

And a diver survey authenticated the presence of a flame shell bed within the Sruth Lagaidh Narrows in Loch Broom.

Colin Trigg, SNH’s project manager for the Ullapool area, said: “The flame shell bed in Loch Broom, although small, is important due to its northerly location.

“Unfortunately these animals have dwindled alarmingly in the past 100 years which is particularly significant for the array of species these beds support.

“Recent evidence suggest the diversity of these beds is comparable to the richest and most diverse reefs in UK inshore waters.”

Previous surveys undertaken by the British Geological Survey (BGS) detailed that the submarine landscape of the Ullapool Approaches preserves excellent examples of glacially-scoured valleys and other erosional bedforms, formed by glaciers flowing towards the Minch.

Here they linked with other glaciers off the west coast of Scotland to form The Minch palaeo-ice stream, one of the major drainage outlets for the last British ice sheet, extending from the mountains of Scotland to the edge of the Continental Shelf.

Martyn Stoker, a geologistt from BGS, said: “Geological surveys carried out in this region are contributing to a better understanding of Pleistocene ice sheet dynamics in general and thede-glaciationn of the last British Ice Sheet in particular – which in this region began at around 15,000 years ago.”

Although previous records had suggested the presence of native oyster beds, horse mussel beds and the European spiny lobster, none were found during the recent Ullapool Approaches survey, run under the auspices of the Scottish Marine Protected Areas (MPA) Project, a joint initiative between Marine Scotland, Historic Scotland, SNH and the Joint Nature Conservation Committee (JNCC).

However, the uncommon ‘tall sea pen’ was found to be widespread, with high population densities present in the inner basins of Loch Broom and Little Loch Broom.