We've had a few visitors this week that were just a bit out of the ordinary. It started when the Mid Wales Classic Car Rally decided they wanted to come and see the Dyfi ospreys - all 71 of them in 39 cars! With some volunteers, high-visibility vests, and some smart parking, we got them all in. Just.

Thanks to all the volunteers that quickly turned from birders to marshallers and then back again

On Monday, we had another visitor: Our 53rd intruder osprey of the season, but this bird had something about him. There was something familiar about him, as though we had seen him before, but could not quite remember where or when.

He was a male bird, had no rings of any kind (only around a third to a half of Scottish ospreys are ringed each year) and had two extremely characteristic markings - those two splashes of white feathers just above the beak. We quickly named him Two Dots.

So characteristic, we should be able to identify Two Dots if he comes back next year

He still looked familiar, so we decided to look back at some videos from last year. Lo and behold, Two Dots had landed on the Dyfi nest on August 21st last year. The head shape was the same, the beak, the chest band, the bleached feathers, lack of rings, sex, everything. And the two dots, of course. His visit was just a few hours short of being an exact year since his last visit in 2011. Unreal.

Two Dots visits on August 21st in 2011 - look at the two white markings above the beak

Here's a video of Two Dots landing on the Dyfi nest in 2011 - Dulas and Leri look on in amazement..

A few people have commented that they thought Two Dots was a fledgling from this year, due to his bronze-coloured feathers. Some ospreys have lighter-colour feathers than others - just natural variation within a population. The pattern of the bronzing is quite different, however, between adults and juveniles. In young birds, the feathers are generally dark brown with the tips and some edges having the bronze colour; the appearance looks quite clinical. Adult birds, on the other hand, have the bronzing on other parts of the feather structure also, particularly on the edges. (I call this bleaching on adult ospreys, although I'm not sure how much, if any, effect the sun has on this phenomenon. It aptly describes the appearance, however, irrespective of morphological accuracy.)

The real give-away is the eye colour, of course - yellow in adults only. (Unless you're Monty, but that's another story!)

Bronzing differences between juveniles and adults: 
Ceulan above, Two Dots below

Monty has some bronzing as well - here he is demonstrating just that:

Watcha looking at, handsome boy?

Ceulan is still with us and Monty is still catching his fish for him. As I write, Ceulan is 89 days old and just at around the average age that British ospreys start their migration. How long will he be with us for before he goes? Who knows, look out for Ceulan's own blog tomorrow.

And finally, many of the warblers that have kept us entertained with their wonderful calls and songs this summer are also now on the move. Their urge to head off to Africa is just as strong as Ceulan's and Monty's. Around a million whitethroats arrive in Britain each year to breed and, just like the osprey, they winter in sub-saharan Africa, over 3000 miles away. This one was just outside the osprey hide yesterday afternoon.

A whitethroat on Cors Dyfi - also preparing from an imminent African departure