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What Egg-xactly is going on?

Posted: Wednesday 5th May 2021 by Kim MWT

MWT Dyfi Osprey intruder MAy 21MWT Dyfi Osprey Intruder over nest May 21

Despite some turbulent weather over the last few days Telyn and Idris are just over half way through incubating their three eggs.

Ospreys typically incubate their eggs for around 37 days before they hatch. Both the male and the female take turns with incubation. This year we have seen Telyn doing around 80% of the sitting with Idris taking his turn so that she can leave the nest to feed, preen and bathe. Idris is currently still providing 100% of the fish for them both. 


Telyn and Idris are just over half way through incubating their three eggs. 

MWT 3 eggs 2021


With Telyn sitting tight and Idris usually not far from the nest we are quickly able to spot changes in their behaviour that indicate when there is another osprey around. These birds we call intruders. Identifying intruders is not always straight forwards but if they do fly close enough to the cameras, with a ringed leg dangling we are able to feed that information into our network of osprey ringers and add data to the sightings and records databases. 

Just yesterday we had a tantilising glimpse of a ringed female osprey who flew very close to Telyn on the nest - unfortunately she did not want to show us the details of her darvic ring. She was ringed on the right leg so we can at least say she was ringed in Wales or England. There is a good chance that she could be a two year old osprey returning to the UK for the first time. 


Telyn sits tight as a female intruder passes close by. 

MWT Dyfi Osprey Intruder May 21


Over the next month we would expect to see and, receive reports of, a good number of two year old ospreys making thier first return to Wales and the rest of the UK. We are especially on the look out for ring numbers KA1, KA2 and KA3, our three chicks from 2019 - Berthyn, Peris and Hesgyn. It would be wonderful to celebrate the safe return of one (or more) of Monty's last brood now we are in the Dyfi Wildlife Centre - a project that would not have happened without him. 


Berthyn and Hesgyn shortly after they fledged in 2019.

MWT Dyfi osprey Berthyn and Hesgyn 2019


It is well documented that the return rate of young ospreys is only around 33%, our average at the Dyfi Osprey Project is a little above this however, we have still only ever record one returnee from a single brood. We were a little surprised then when a KS7 and KS8, a brother and sister osprey from 2018, appeared at the Dyfi nest a week ago. These birds were not far from their natal nest at Clywedog (just south of the Dyfi).

This is the second year that KS8 has been sighted back int he UK but is the first time her brother has been spotted. We were delighted to share the news with our colleagues at the Clywedog project. 



You can rest assured we will be eyes to the sky over the next few weeks and even more egg-citingly you can now visit us should you wish. Our online booking system is working well and we are eagerly awaiting the next update from Welsh Government on the 17th of May that will hopefully mean we can open a few more of the facilites in the Dyfi Wildlife Centre. 

We would like to be able to open the osprey interpretation area, just in time for hatching, which could happen anytime from about the 19th May. We will of course keep you posted with any changes to opening and booking a visit. 






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