Sir, – I must take issue with Conor Skehan’s response to Oonagh Duggan’s article of May 21st (Letters, May 25th).Skehan attributes ecological scarcity to the fact that Ireland is at the extreme edge of Europe, and that many species are naturally sparse, fragmented and unstable. That two-thirds of our wild birds are in danger is due almost entirely to human activity, both at an island level and internationally.As a child, 80 years ago, we lived within five miles of Dublin city centre. Our summer nights were disturbed by the calls of corncrakes in the adjoining fields. The corncrake was widespread throughout Ireland, before urban sprawl and agricultural intensification wiped out its habitats. Similarly, huge flocks of other species, such as lapwings and golden plover, were common, much to the delight of shooters.Populations are not inherently small-scale; we have made them so. This is precisely why we have a crisis, and an ecological emergency. – Yours, etc,ROBERT S MYERSCOUGH,Dunlavin,Co Kildare.