The decent weather is holding on by its fingertips (there's a risk that a storm may pass over during the night), and the modest warmth is bringing out the insects. And where there are insects there are birds, and there are none better at chasing insects than the swift.
Swifts are quite astounding creatures. Living almost permanently on the wing, they touch land only to lay and incubate eggs. Even mating is carried out in flight. The youngsters can remain airborne for three years after fledging, and at this time of year when there are young mouths to feed the adults may gather as many as 100,000 insects in a day. According to the RSPB they average around 500 miles a day in flight, or 2 million kilometres in the course of a lifetime. They are no slouches either, and can reach speeds of over 100 kph (around 70 mph) in level flight. Fortunately they weren't at top speed today, and I had the advantage that they were circling in what was for swifts a relatively predictable pattern. 
After swifts, photographing house martins is relatively easy. They're also great insect catchers, but they are a little slower and do pause occasionally for breath.
When swooping for insects over the pond, house martins thoughtfully include a slight stall as they grab their target (unlike the swifts who barely slow down at all).
Back home, the fox cubs are still providing a nightly show. Just a couple of quick shots. to wrap things up.
Camera note: all bird shots taken with the Canon 7D and EF 400mm f/5.6L USM lens. Fox cubs photographed with the EF 24-105 F4L IS USM lens.
derWandersmann
21 Jun 2012That second shot of the swift is a knockout, Words! And the little tussle between the two cubs is definitely amusing. That last "portrait" is exquisite!
BTW … haven't seen Shutterbug in a while?
anonymous
21 Jun 2012Anonymous writes:
That last closeup shot! Wow!! Love it.
Marilyn
SittingFox
22 Jun 2012Somehow when I read the title of this blog post, my brain translated it as 'swift foxes', which struck me as unusual South Downs fauna :right:
Wonderful shots of the swift. Perfect flying machine.
gdare
23 Jun 2012Swifts, house martins and swallows – they all look almost the same to me. In Serbia we only had swallows and they look a bit different than swallows in Canada. Only a tail reveals them 🙂
Words
23 Jun 2012Darko, they're really very different when you look closely! Not always easy when they are flying overhead.
Words
23 Jun 2012dW, thanks. Those are probably my best ever shots of swifts. I was fortunate that they were coming in quite close but with no distracting background behind them (plays havoc with focusing).
The foxes are proving great fun!
Words
23 Jun 2012Adele, a swift fox would be something round here. Swifts are quite amazing birds.
Words
23 Jun 2012Marilyn, thanks! Nice to get some portraits while they're young.
derWandersmann
23 Jun 2012I was noticing how their swept-wing design anticipates the early MiGs that were shooting us out of the sky in Korea.
Words
23 Jun 2012dW, aircraft designers are looking at swifts to learn about 'wing morphing'.
Mickeyjoe-Irl
27 Jun 2012Originally posted by Words:
They do look built for speed.
Words
28 Jun 2012Mick, they can do a fair lick in level flight, but its the manoeuvrability that is so astonishing, and sheer endurance.