HC Deb 26 July 1985 vol 83 c888W
Mr. Onslow

asked the Secretary of State for the Environment what studies he has made of the increase in the number of magpies and carrion crows in England and Wales, and the effect of this on the song bird population; and if he will make a statement.

Mr. Waldegrave

Estimates based upon the common bird census carried out each year by the British Trust for Ornithology indicate that the magpie population has increased by over one third in the past 20 years while the carrion crow population has about doubled in the same period.

A 1983 study of magpies found that eggs and young birds form an insignificant part of the species diet and this is likely to be true of the crow. There is no scientific evidence that predation by magpies and crows has a marked effect on song-bird population.