Tuesday, 27 January 2015

Roe Deer, Dormice and Over Management

From  the most recent of  the long series of fascinating articles by Mark Fisher of the Wildland Research Institute.

 We don’t manage landscapes for wild deer
Over-hunting led to roe deer becoming scarce in England in Medieval times, becoming extinct in central and southern England and all of Wales by 1700 (7). However, after 1800, several reintroductions from Scotland into Dorset, Sussex and East Anglia, coupled with natural spread into northern England, has reinstated roe deer in most counties. As with all species that are able to thrive in spite of us, we control them through culling – an estimated 350,000 deer are killed each year (8,9) but I can’t tell you how many of those are roe deer as there is no official count. The common dormouse is also a relatively common and widespread species across the middle latitudes of continental Europe (10). However, in England, it is confined to southern counties when its distribution would have covered most of England (11). In retrospect, I wish I had not alighted on the dormouse as an example, since efforts to maintain and increase its range smack very heavily of the over-management paradigm, the dream constellation for the conservation industry of a cute animal because it tucks its tail over its face as it rolls tightly into a ball when it is hibernating for half the year, or when in daily torpor during spring and early summer, and the prescription that it does better in coppiced woods and with artificial nest boxes (12).
The coppicing is a bit of a logical fallacy, justified on the basis of feeding habits: dormice are specialist feeders in that they require a wide variety of arboreal foods including flowers (nectar and pollen), fruits (berries and nuts) and some insects, their food supply thus depending over the summer months on a succession of fruiting trees and shrubs (13). This implies a woodland with a high diversity of tree types and a species-rich understorey that is not shaded-out by taller trees that would inhibit flowering and fruiting. Dormice do not normally travel far from their nest, usually less than 70m, but they avoid activity on the ground, preferring to move among trees having plenty of near horizontal branches, and being able to climb between the understorey and canopy without difficulty in what have been called “three dimensional arboreal routes” and which offer visual protection from predators (13). You might then wonder how that fits with the twin obsessions of the conservation industry of grazing and coppicing woodland. The grazing will just clear out all that understory, whereas the coppicing destroys vertical and horizontal structure. I have only once seen recognition that coppicing is devastating to the dispersal ability of the dormouse (14):
“Large-scale coppicing renders extensive areas unusable for up to five years by creating open ground which the animals are reluctant to cross. Depending on the pattern of felling coupes, on small sites this can act as a barrier to Dormice reaching potentially important food resources. This can put pressure on individuals and reduce a population to vulnerable levels”

Full article here


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