I'll let you into a bit of a secret. Three weeks ago, myself and three colleagues from DOP, Alwyn, Posh Pete and Justin, popped down to the mouth of the Dyfi River for a couple of hours. Why? We've seen more ospreys on the Dyfi this year than in any other, and by quite a margin. We wanted to see if we could spot any ospreys fishing or flying around. It was a day we won't forget in a hurry.

First off, we saw this fellow perching right bang in the middle of the Dyfi Nature Reserve, owned by the Countryside Council for Wales. It looked like a male to me, but had quite a broad beak so difficult to tell from the 250m distance we were away.

Osprey, possibly male, but not ringed

Next up, Alwyn shouts "OSPREY, TWO O'CLOCK". In very murky conditions, this magnificent female was circling high above the estuary, only this time we could see leg rings. A BTO metal ring on the left leg and a white Darvic ring on the right. Unfortunately, we couldn't make out the ID characters on the Darvic, but being on the right leg we know she must be a Welsh or an English bird (Darvics go on the left leg in Scotland). Between 2008 and 2010, seven female ospreys have been ringed as chicks in the Glaslyn nest just 28 miles north of the Dyfi. Surely there must be a high probability that this bird is a Glaslyn osprey looking for a mate?

A ringed female osprey - is she a Welsh bird?

"TWO OSPREYS TOGETHER BEHIND - EIGHT O'CLOCK"  - Alwyn was on form. "It's like being in the Gambia" roars Posh Pete. Sure enough there were two ospreys soaring together very high up as if they were pair-bonding, ready for next year. In all, there were four ospreys in view at the same time, I didn't know which direction to point the camera next.

The female of the pair had a leg ring, a Darvic, and this time we could make it out. It was blue with the numbers 12 clearly etched in white on the ring.

Blue 12 - moulting some primary and tail feathers

It was fantastic seeing Blue 12 again - she had already visited the Dyfi nest on May 21st. She is a Rutland Water osprey born in 2010 at Site N. She is also related to Nora. Blue 12's mother is Nora's sister, which makes Ceulan a cousin to Blue 12.

Blue 12 tried to land on the Dyfi nest in May - fish in talons

So the two-year-old Blue 12 had been positively identified on the Dyfi on two separate occasions around seven weeks apart. She was next identified a week ago - at Rutland! Volunteers Monica and Tony spotted her at Manton Bay on July 23rd. Fast forward six days and you'll never guess who lands on the Dyfi nest for over 50 minutes..

Blue 12 sightings this year:

May 21st - Dyfi
July 9th - Dyfi
July 22nd - Rutland
July 29th Dyfi
July 30th - Dyfi

So what's going on - what is Blue 12 doing? As adults, ospreys need two fundamental things in order to breed: Good fishing areas and a good nest site close to these fishing sites. Blue 12 is looking around for a nest and preferably one with a single male with it. It's too late this year to breed, but Blue 12 will be making mental notes of all the nest sites she has visited this year, her first year back in the UK as an adult, and will hopefully be back in 2013 to make claim to a nest and mate of her own.

Ceulan - saying 'Hello' to his cousin from Rutland

Males are slightly different. Whereas females will roam around until they find a suitable male holding a nest site and home range, a male will return from Africa and look for suitable areas to set up a nest. They prefer to take over a vacant nest (like Monty did). They will,of course, build their own, but herein lies a problem.

Hundreds of years ago, there would have been numerous good areas to set up a nest next to a good fishing area. The irony is that today, the good fishing areas are still here - but the nest sites are not. Ospreys like to nest on damaged or dead trees and even on fallen trees if they are high enough off the ground. The problem is that over many years these kind of trees have been removed to make way for developments, agriculture, roads and so on. Others have been removed because of health and safety concerns - if they've been struck and damaged by lighting, for example, perfect for ospreys. Furthermore, there is an artificially low number of ancestral nests due to centuries of persecution, so male ospreys are seldom in a position to take over a nest once its owner dies.

This balance between prey availability and the number of osprey nesting sites needs to be re-calibrated. We have a situation where there are fishmongers everywhere but no houses to live in, and of the houses there are, none of them were built before 1960. Imagine that!

On a recent visit, Roy Dennis demonstrates a perfect location for a nest site on the Dyfi

So there you go, the secret is out! There are far more ospreys around than we think - many of them young birds looking for nest sites. We've just filled in our 50th "Intruder Sheet' yesterday. Imagine saying that just five years ago - 50 separate sightings of ospreys on or around the Dyfi nest since April - and those are just the ones that we have seen, there will have been many others. I will write a blog after the season finishes about building more nest platforms but, for now, it seems that the case for putting up more osprey nests is as compelling as at any other time.

Oh, and the male bird that Blue 12 was seen flying around together with for a good half hour as if they were pair bonding? Monty.

Nora sees off her niece Blue 12, but will she have more intra-family competition next year?

UPDATE - AUGUST 1st. Many thanks to Tony and Monica for getting in touch. Here is their image of Blue 12 when she was at Rutland on July 23rd. Excellent shot Tony.   © Tony Shooter