Sir: S G Armstrong's observations (letter, 19 April) are based on a garden hedgerow. The national picture is very different.
In areas where there is sufficient habitat for nesting songbirds to conceal their nests in thick cover, the population increases and decreases of songbirds and magpies have been shown to rise and fall approximately in tandem. This has been determined from detailed British Trust for Ornithology surveys (C. Mead, BTO.Feb 1992).
The problem in a park or garden is that the habitat has been developed primarily to meet human requirements. Nesting habitats for songbirds are often not dense enough and nests can easily be found by magpies and other predators.
On shooting estates where magpie populations are controlled by the methods advocated by S G Armstrong, it is true that songbirds benefit from reduced predation, but songbirds on shooting estates also benefit from the abundance of habitats established and maintained for the game birds.
There are predators far worse than magpies: people who trim their hedges during spring and summer, thereby revealing nests to predators or causing nests to be deserted; cats and cars who each kill millions of birds a year.
Lymington, HampshireReuse content