Friends of the Ochils Newsletter 21: Autumn 2002
Blanket coverage
The previous FotO newsletter included a few words from Jonathan Willet, biodiversity officer for Stirling Council. His Clackmannanshire counterpart, Lynn Campbell, adds some thoughts about bogs.
WHAT ARE BLANKET BOGS? Does Clackmannanshire have any? And, if so, do they matter? Blanket bog is a globally-restricted peatland habitat confined to cool, wet, typically oceanic climates. It is, however, one of the most extensive semi-natural habitats in the United Kingdom and ranges from Devon to Shetland.
In Europe, the blanket bogs are confined to the UK, Ireland, south-west Iceland and western Norway. Throughout the rest of the world, the habitat is found only on the east coast of Canada, in southern Alaska, on part of the north American Pacific coast, the southern tip of South America and north-east Asia along with parts of southern Tasmania and New Zealand's South Island.
There are two main types of peatlands: ombrotrophic and minerotrophic. Ombrotrophic peatlands are fed exclusively by precipitation while minerotrophic peatlands are fed by ground water and/or streams. There are in turn two types of ombrotrophic peatland: lowland raised bogs and blanket bogs.
So are there any blanket bogs in Clackmannanshire?
Yes! The wee county can boast two extensive areas of blanket bog: Alva Moss and Menstrie Moss, located in the Ochils near Blairdenon Hill. The Alva and Menstrie mosses cover an area of around 324 hectares, with Alva Moss being the larger of the two at 300 hectares. Both sites occur at an altitude range of 520-560 metres above sea level, with the depth of peat varying from 30 millimetres to a maximum of four metres. The mosses form the headwaters of the Alva and Balquharn Burns draining to the south and the Finglen Burn draining to the north.
What sort of things live in blanket bogs?
Bogs support a variety of plants and animals which have adapted to this environment. Sphagnum moss, which grows in nitrogen-poor soils, is mainly responsible for the continued growth of the bog. If you look closely in the moss you may also see sundew, a carnivorous plant that catches insects with its sticky hairs. The high water content of bogs makes them an ideal environment for wading birds and for many birds of prey. The blanket bog species action plan in the Clackmannanshire Biodiversity Action Plan lists a variety of species associated with blanket bogs, including skylark, golden plover, curlew, common frog, mountain hare, black grouse, crowberry, cranberry, cross-leaved heath and cottongrass. These are just a few of the species, rare and common, that live in and around Alva and Menstrie mosses.
So why are bogs important?
Peat bogs provide us with a host of products and services essential for human life and wildlife. As noted above, bogs support a wide variety of both common and rare/endangered plants and animals. They also store carbon through many years of accumulated plant growth, filter drinking water, are a source of ancient habitats and provide a living archive. Scottish bogs are also globally important as there are limited conditions in which they can exist - and Scotland is certainly the place for cool and wet conditions.
What are the current threats to bogs?
Scotland's blanket bog accounts for some 13% of the total land area. A 21% reduction in size between the 1940s and the 1980s has been caused by a variety of human developments, including:
- extraction for burning and gardening
- woodland expansion such as conifer plantations
- draining the land to provide rough pasture
- erosion through a combination of grazing, burning, climate change and even hillwalking
- air pollution - this damages bogs, in particular vulnerable plants such as the mosses
The activity with the largest impact on peat bogs is the extraction of peat for amateur gardening.
What can you do?
First, do your best to prevent any more destruction of peatlands by only buying peat-free compost from garden centres. The following organisations have plenty of information on where to start:
- The Scottish Wildlife Trust is running a campaign for lowland raised bogs, the other type of ombrotrophic peatland. The SWT is promoting the use of good-quality alternatives based on wood waste, coir and green compost. These may need handling differently to peat, but can give excellent results. For information, look at: www.swt.org.uk/what_ we_do/campaigns/peatlands.asp
- The Irish Peatland Conservation Council has come up with a "peat-free garden campaign" to help promote awareness amongst gardeners. www.ipcc.ie/peatfreehome.html has plenty of information.
- Plantlife - a membership charity dedicated exclusively to conserving all forms of plant life in its natural habitat - is working towards peatland preservation. See www.plantlife.org.uk/html/campaigns_ peat.htm
What is happening in Clackmannanshire?
The Clackmannanshire Biodiversity Partnership is working towards promoting awareness of our local bogs among the people of Clackmannanshire. As a starting point, this summer a "habitat action plan" for blanket bogs was written for the consultation draft of the Clackmannanshire Biodiversity Action Plan (available at local libraries and at the council itself. Please note that comments on the plan are still being accepted; input would be appreciated no matter if this is the first time you have heard about biodiversity.
For more information on blanket bogs or on biodiversity in Clackmannanshire, please contact Lynn Campbell on 01259 452639.