Bioblitz Blog: Boggy Biodiversity
Get up close and personal with raised bogs and you'll see they're full of colour. Scott Shanks, Project Lead for Raising the Bogs, reveals some of the hidden jewels you can discover across our local boggy landscapes.
In the past 200 years there has been a dramatic decline in lowland raised bogs. In Scotland, it is estimated that over 80 % of raised bog habitat has been lost due to agricultural intensification (drainage), afforestation (planting of commercial timber) and commercial peat extraction (a major source of peat-based gardening compost).
Peatlands in the Garnock Connections landscape support a diversity of species that are specially adapted to the unique and often harsh conditions found there. Most of the plants and wildlife you find in the wider countryside wouldn’t be very happy in the soggy, acid, low nutrient conditions of a healthy bog, unless it had been altered by drainage. Sphagnum mosses are the foundation of peat bogs, and many species can be found growing together or in specific habitat niches within the bog. Some mosses such as the colourful Red bog-moss (Sphagnum capillifolium) thrive in slightly raised, dryer areas, while others such as Feathery bog-moss (Sphagnum cuspidatum) tend to be found submerged in bog pools. Acid-tolerant fungi and the wonderful chalky grey-green Cladonia lichens also do well on bogs.
Bog plants including Cross-leaved heath (Erica tetralix), Cotton grasses (Eriophorum sp.), Cranberry (Vaccinium oxycoccus), Bog rosemary (Andromeda polifolia) and Bog asphodel (Narthecium ossifragum) can be found in these damp, acidic peatland habitats. Insectivorous sundews (Drosera sp.) thrive in nutrient-poor bogs by using sticky blobs of honey-dew on their leaves to catch small invertebrates, and absorb nutrients from their decaying bodies!
Bogs are an important habitat for many species of ground -nesting birds including Hen harriers (Circus cyaneus), Skylark (Alauda arvensis) and Meadow pipits (Anthus pratensis). The wet ground and open views afforded across bogs means that they provide relatively safe roosting sites for wildfowl and waders such as Snipe (Gallinago gallinago). Short-eared owls often patrol the edges of raised bogs looking for bank voles (Myodes glareolus) and other wee rodents in the grassy lagg fen boundary surrounding bogs.
Common lizards (Zootaca vivipara) and Adders (Vipera bera) can often be found on bogs, and amphibians such as Palmate newts (Lissotriton helveticus) and Common frogs (Rana temporaria) will breed in the acidic bog pools.
Many invertebrates can be found on bogs including habitat specialists such as the Large heath butterfly (Coenonympha tullia) which uses cotton grasses as its caterpillar food plant, and the Black darter dragonfly (Sympetrum danae), which breeds in vegetated bog pools and can be seen zooming over the bog hunting flies and other insects in the late summer and autumn. Other invertebrates found on bogs include the Heiroglyphic ladybird (Coccinella hieroglyphica) which specialises in eating Heather beetle (Lochmaea suturalis) larvae; the spectacular Emperor moth (Saturnia pavonia), which is the UK’s biggest moth; and the fabulous Green hairstreak butterfly (Callophrys rubi), which uses Blaeberry as its caterpillar food plant.
On healthy intact bogs, lots of aquatic bugs can be found in shallow bog pools including Common hawker (Aeshna juncea) and Four-spotted chaser (Libellula quadrimaculata) dragonflies and a huge number of water beetles including the Greater diving beetle (Dytiscus marginalis). During the restoration of peatlands, when ditches are blocked and the water-table restored to allow peat-forming Sphagnum mosses to recolonise, this can result in a wonderful increase in the number of dragonflies and damselflies present on a site.
The International Day for Biological Diversity on the 22nd May is a perfect time to go visit a raised bog near you and look for some weird and wonderful wildlife and plants. Sundews and Bog asphodel will be in flower and male Green Hairstreak butterflies will be zipping about defending their territory and looking like living jewels. Don’t forget to record what you find.
Scott is the project lead for Raising the Bogs and RSPB Scotland’s Conservation Officer for Central Scotland.
Follow him on twitter @ScottShanks01
For more information about Raising the Bogs, including how you can get involved, click here.