Bizarre breeding behaviour of a Black Sparrowhawk

Abstract

The Black Sparrowhawk builds a large, stick platform nest, high up in a tall, often alien tree. The cup of the nest is lined with green leaves. Given this, I was very sceptical when a birding friend was contacted by a lady in Somerset West claiming to have a Black Sparrowhawk sitting on an egg on her lawn. The bird had been there since the 13th September 2017 and seemed to be quite content.