I have also noticed it with other little creatures aswell, butterflies and bees don't seem to be around so much now either.

Some years ago I was involved in a television series about gardens.

Visiting one due to be remodelled, I was struck by the hum of insects and the number of butterflies etc. but, having seen the plans, I knew all that wildlife would be gone after the remodelling had been done, the garden would be almost clinically clean.

Of course along with those insects, the birds that relied on them would also go.