Management of the dunes
Plagioclimax vegetation
Much
of the dunes at Magilligan would have developed into forest were it not
for the introduction of rabbits. Rabbits are not native animals in Ireland
or Great Britain. Introduced as an economic resource with skins being
harvested from the warrens, these creatures preserved the dune vegetation
by preventing the encroachment of trees and bushes. As such this is an
excellent example of plagioclimax vegetation. In 1954 myxomatosis was
introduced to Ireland. This is a viral disease which is present in South
American rabbits but to which they are largely immune. When scientists
discovered that it was generally fatal in European rabbits, they saw the
virus as an opportunity of controlling rabbit populations in countries
where it had been introduced and had multiplied to pest proportions. Myxomatosis
was first used in Australia to control rabbit numbers there. Following
its success in reducing numbers there, it was introduced into South East
England in 1953 and spread, or was spread, to most parts of the British
Isles by 1954. In some areas the mortality rate for rabbits was 99.8%
(Lockley, The Private Life of the Rabbit 1964).
In Magilligan, as elsewhere, rabbit numbers have declined sharply. This should have allowed the natural processes of vegetation succession to operate once again. However, in some areas of the Magilligan dunes, grazing animals (particularly cattle) have been introduced deliberately to retain the plagioclimax vegetation. These animals are placed on the dunes in a controlled way tp restrict the encroachment of forest plants into the dunes. However the burnet rose and the sea buckthorn are too thorny for the cattle to graze.
Recreation
Recreational use of dunes has an impact on the vegetation. Marram, in particular, has little resistance to trampling and, when damaged, the binding properties of the plant are lost. When the bare sand is exposed to the wind without the roots of the marram securing it, a blow-out can develop. This is a concave area of exposed sand on the face of a dune. Given time blow-outs can revegetate, but in extreme cases the entire dune ecosystem can be threatened in heavily used areas. In Magilligan beach access has been restricted by the use of fencing. The permitted access routes have boardwalks constructed to minimise damage to the vegetation.
Follow the links in the diagram below to explore the dunes.
