There is only one lake in Scotland: The Lake of Menteith north of Glasgow; the rest are lochs, with smaller ones being called lochans or dubh lochs. Around the coast, some marine inlets are called sea lochs; in fact, some of them are like small Norwegian fjords. This book, however, is about freshwater lochs. Scottish lochs vary tremendously in character, from the great, deep, foreboding waters, like Loch Ness and Loch Morar with their huge depths and stories of monsters, through open, fertile lochs set among rolling farmland, to the tiny hill lochans of remote peatlands and the high mountains. The variation is so great from west to east, from north to south, that our story is centered on the lochs of the eastern part of the Highland region, in particular those that are in the catchment of the Moray Firth and especially the lochs that are on the coastal plain or close to it.
Our loch is just an ordinary loch in many ways. The birds, mammals, fish, amphibians, insects and plants found there are to be seen on many lochs throughout the Highlands. Some of the wildlife found on other lochs is never seen here because the conditions are not right, while some creatures I see here will not be observed on other lochs in the district. This is a rich, busy loch, surrounded by lush vegetation and sheltered by fringing woodland of birches and pines. It has marshy islands covered with lichen-encrusted willow bushes and surrounded by sedges and bulrushes; this makes a great difference to wildlife.
There are similar lochs dotted throughout the lowlands surrounding Moray Firth, often set in hollows left by the action of the ice-age glaciers and fringed by woodland and farms. They are usually productive lochs with a rich growth of reeds, sedges, bulrushes and flowering plants such as water lilies and bogbean. Often farm fields may run to the water’s edge and human presence is frequent through fishing, walking and sometimes through water sports. The wildlife is often centered around wildfowl and waders, but nowadays these lochs are also frequented by hunting ospreys as well as ranging otters.
There are two large lochs in this district. Loch Ness is a dramatic loch set between the mountains of the Great Glen. It is steep sided and was formed by the movement of the earth’s tectonic plates. It is 24 miles long and plunges nearly 900 feet in depth. This loch never freezes because of its depth; in fact, the inherent heat of the loch also provides a microclimate around the lochside and often the roads close to the loch remain ice free when most other roads are icy. Because of its steep sides it is rather poor for wildlife, with the exception of its alleged most famous inhabitant. The other large loch is much, much smaller and is very shallow compared to Loch Ness. It is only 1 1/2 miles long and half a mile wide, but Loch Eye is a haven for wildlife, especially in winter, when thousands of ducks, geese and swans use its water for feeding and roosting.
In the lower hills and glens, often set among forests of pines and birch woodlands, are a range of medium to small lochs; some are the most beautiful, picturesque lochs in majestic surroundings. The lochs nearest to my home nestle in the ancient Caledonian pine forest. They were created during the ice age by lumps of ice that slowly melted in situ during the glacial drift; they are called kettle-hole lochs. These lochs are not as productive as the low-ground lochs on the richer soils, as they tend to be more acid and peaty coloured, often with water the color of whisky. But they are favoured haunts of some rare species, such as black-throated divers, Slavonian grebes and goldeneye ducks. In winter, they are often choice roosts for wildfowl and gulls during the night, affording the birds security and safety from scavenging foxes.
Finally, there are the high-level lochs and lochans nestling in the wide, bare moorlands and in the high mountains looking down on the Moray plain. Some are peaty pools fringed with red and green sphagnum mosses, with water so black that you can hardly see your hand through the freezing water. These pools are the nesting sites for red-throated divers and washing places for the plaintive golden plover of the heathery moors. The high mountain lochs are often crystal clear on a granite bed, almost devoid of plantlife. They are not wildlife lochs, but they add considerably to the beauty of wild places.
“The Loch: A Year In The Life Of A Scottish Loch”