The Loch Ness Clan has been in existence since at least the 10th century. Most likely, they had contact with many neighbouring clans including the Scone Clan, and the Scone Clan. It doesn't seem likely that they had any contact with Demona's Clan as she seems to think all gargoyles were eradicated from Scotland by the Hunters.
The Clan lives in partially submerged caverns beneath the Loch and their primary misson is to protect and safe guard the few remaining Loch Ness Monsters that still survive under the lake's surface. It is unknown why they did not come to the aid of the creatures when Sevarius captured one, though perhaps they were unable to locate his base of operations.
Easily the most aquatic of surviving gargoyles, the Loch Ness Clan has adapted well to their watery dwellings. Their wings are shaped as large manta-like fins and their lower bodies are quite dolphin-esque. It is unknown how these features have affected their ability to walk on land, glide, etc.