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Message: <blockquote data-quote="KnockerNorton" data-source="post: 1684473" data-attributes="member: 66452"><p>Studies show that Sparrowhawks take up to 25% of breeding adult tits in spring. This is much more than the "weak, old and unwary". Other studies have shown that high numbers of some species [blackbirds] can create 'predator traps' for other species at a lower density [Song Thrush] by propping up Sparrowhawks. So Sparrowhawk predation really can have a significant and disproportionate impact on some species, reducing their breeding density. If, for example, a wood has 10 pairs of Blue Tits and 1 pair of Willow Tits, its the Blue Tits that makes it attractive for the Sparrowhawks and encourage them to stick around and breed. If they predate 25% of the Blue Tits, there are still plenty left because they can breed at high density. But if they take one of the Willow Tits, then that's a local extinction. This kind of interaction of factors is a serious contender for the decline of some species.</p></blockquote><p></p>