Writing in early 1917 and far from home, the poet Edward Thomas noted
how the sight of four or five planes ‘weaving and wheeling overhead’ reminded
him of the kestrels that he used to see over the Shoulder of Mutton Hill near
Petersfield. Such recollections rekindle my own memories of days spent near
Petersfield and of the kestrels that would haunt the skies, scanning the ground
below for small mammal prey.
Throughout my childhood the kestrel was regarded as our most commonly
seen bird of prey, a familiar species that I was certain to see from a car
journey of any distance. Long-term monitoring data from the British Trust for
Ornithology (BTO) support this, showing the kestrel population of the mid-1970s
to have recovered from the effects of organochlorine pesticides and to be at a
peak not since matched. This peak was, however, short-lived and there was a
substantial decline over the following decade, which left numbers well below
the level that had been achieved. This new decline has been driven by a period
of agricultural intensification that left our farmland much changed. The loss
of many thousands of miles of hedgerows and field margins brought about a
decline in the numbers of small mammals and large invertebrates upon which our
kestrels depend.
We are not alone in having lost so many kestrels; it is a pattern
repeated more widely across Western Europe, underlining how the changing
demands we have for cheap food, produced in ever increasing quantities, have
changed the landscape fundamentally. With less space for wildlife it is
inevitable that those species at the top of the food chain will show pronounced
changes in their numbers and abundance. The pattern of change seen in our
kestrel populations shows some regional variation; for example, the species
benefited during the period of afforestation, where many hundreds of hectares
of coniferous plantation were established. However, as these new forests
developed so they shaded out the swards of rough grassland between their ranks
and with this loss went the field voles and their kestrel predators. The
kestrel remains common enough to remain familiar and to haunt the texts of
today’s nature writers. Let’s hope it remains a living part of our countryside
and not one consigned to our literary heritage.
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