Imagine that Coll is shaped like a fish (stay with me on this), a fish swimming north east. The RSPB reserve is at the end of the body and the thin part before the tail starts. Got the picture? The land owned by the RSPB includes a variety of habitats; moorland, farmed fields, wet grassland, sand dunes and Machair. Some of it is managed by the RSPB staff and some is under tenancy agreements with farmers.
Today was my first ever experience of Machair, a habitat unique to Scotland and Ireland. In Scotland you find it on the Uists, Islay, Colonsay, Tiree and Coll, but as I found out it is different on each island, is farmed in different ways and the habitat has never been properly defined. Its character comes from the influence of shell sand which builds up into huge dunes and also gets blown onto other land making the unique flower-rich grassland which is Machair. In some places, like the Uists, the low lying Machair is at risk from erosion because of sea-level rise but seemingly not yet on Coll. This year, RSPB staff started taking photos of the Machair and dunes from fixed points and will retake photos from exacly the smae point in a few years time to see if the Machair and dunes are eroding.
The changing climate may be having other impacts, or it might just be the weather. April was the driest April ever experienced on Coll and thanks to the jet stream which temporarily sank southwards this year they have had a fantastic summer – sorry if you are reading this in England. The Machair plain 2 years ago had no flowers because the light sandy soils were too dry – it was nearly too dry again this year. Conversely, in the past 3-4 years increased rainfall in winter has meant that the land stays wet and means that the reserve staff can’t use machinery on it in March like they used to. Wetter winters, drier summers and unpredictable extremes of weather are all likely to be the way the climate changes in Scotland.
On Coll it’s impossible to say if climate change is having an impact now on the natural environment because there are no clear signs and no patterns emerging, but we are watching and waiting.
Sorry no pictures – I forgot to bring the lead which links the camera to the computer. Doh! I’ll post some on the blog at the weekend.