'New research recently published in the Journal of Applied Ecology showed that where there were no magpies present, the reproductive output of song thrushes was much greater. This was well illustrated by two maps, one showing the distribution of magpies in Britain, the second showing the breeding success of song thrushes, and they demonstrated perfectly that where magpies were absent song thrushes thrived.'YES! And how many countless other species of songbird too?
LINK: http://www.songbird-survival.org.uk/predators/magpies/
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