Swifts and bats in the Triangle

Mick Delap writes:

It's spring. And the Triangle swifts are back (four seen overhead). But how many will there be all told this year? And will they nest under the Davy's Wine Store eves again? I will be watching out - to see if there is anything more we can do to help this severely endangered, but gloriously exciting, Triangle resident.

I have also seen what for me is a new Triangle species - bats hawking in the dusk over our Egerton Drive garden. Do other gardens have regular sightings of bats, or is this a new arrival? All thoughts and observations gratefully received.
mick@delap.plus.com

The RSPB says:
Where and when to see swifts:
In the sky in summer, April to August, often very high. They never perch on wires like swallows. Towards dusk you might see excited screaming parties of them careering madly at high speed around rooftops and houses, often low.
What they eat: Flying insects and airborne spiders.
www.rspb.org.uk

The Bat Conservation Trust says:
Food: A common pipistrelle can eat over 3,000 tiny insects in a single night! You can help provide food for bats by planting a wildlife friendly garden.
How do bats catch their prey in the dark?
Bats are not blind, but at night their ears are more important than their eyes. As they fly, they make shouting sounds. The return echoes tell them about anything ahead of them, including the size, shape, and direction of an insect. This is echolocation - locating things by their echoes.
Flying: Bats are the only mammal that can truly fly (rather than glide). www.bats.org.uk