Time for a change?

For twenty years now, peregrine falcons have nested on the east side of the ancient stone tower of Derby Cathedral. They use a wooden platform that we were given permission to install there back in April 2006, and which needed to be replaced in 2016. Late last year that replacement itself suffered a failure of its base, and we had to quickly remove all the loose stone and gravel into which the birds scrape their nest. 

The location of the platform, as you probably know, requires abseiling by experienced mountaineers who are also skilled in mounting and maintaining the web cameras which bring the live pictures to you. The project has been fortunate to have Nick Moyes (and his climbing buddy, Nick Evans) to perform these abseils every year. We have discussed how to ensure this structural failure can't happen again and concluded that completely redesigning and replacing the existing platform using new, longer lasting materials (with which we are not  familiar), and finding the necessary funding and construction expertise, will not be possible in the short time frame available before the forthcoming breeding season.

Looking around the UK, we see quite a few nest boxes placed on tops of buildings rather than half way down them - and for obvious reasons! Most sit directly on the rooftop itself, but these only work if there is no access or disturbance to the roof while the birds are nesting, something which isn't possible at Derby where flags have to be changed occasionally and routine inspections made. 

And then we encountered this video of an experimental nest box being installed on a church rooftop in Ramsgate. It is enclosed and faces out through one of the stonework's crenellations. Such a box, we thought, might well work for us too. So we decided to apply to the Cathedral authorities to allow us to install a similar box, albeit just as a temporary, emergency measure for this summer to ensure our birds don't move away or try to find somewhere else to nest in the city.

Our plan would be to site the box in the right hand crenellation above the platform when viewed from below - eventually with a camera installed somewhere within it.

After submitting our proposal and drawings to the Cathedral staff, we are delighted to say that they have agreed to our plans. The box will have to be 'temporary' for a number of reasons:

1. there is a chance the birds may not find and use it this summer;
2. the cathedral roof has major renovation works planned for late 2026;
3. the nest box will need to be moved or dismantled when roof works are undertaken.
4. we will need the further permission of the Cathedral's Fabric Committee for any 'tower top box' to become permanent.
5. we can learn from the construction of this temporary box and improve upon it if necessary.

Of course, if the birds don't adopt it, we'll simply have to go back again to installing a new, more resilient platform lower down for next year. But then we'll have the time to plan and fund it properly. But we are hopeful this alternative approach could offer a long term, easy-to-maintain solution that not only the birds, but also the Cathedral are happy with. It would avoid anyone having to abseil down twice a year for ringing and for maintenance, and ensure our Peregrine Project has a long-term future.

Meanwhile, once the new box has been constructed, we will abseil down to the old platform, check its condition and remove the old base to prevent any attempt at futile egg-laying. We will probably leave at least one camera in place to see what use the birds make of the remaining perch while they are hopefully nesting in the new box up above.

Peregrines are usually very 'site-faithful' and are always very keen to nest, so we are really hopeful that they will adopt the new 'top box' as they have done elsewhere in the UK. In terms of timing, the birds can adapt the time of egg laying to the situation in which they find themselves. In the first year (2006), the platform could not be installed until early April, and yet the birds nested successfully in it, quite some weeks later than in any subsequent year.
So while we will try to get a top box installed as soon as possible the abseil down to the old platform is even more dependent on the weather - and abseiler availability - and might take longer.

The necessary timber and materials have now been ordered, and it's hoped that we can start work this coming week, depending upon the weather. Please bear with us and remember that all the planning and blogging about this is carried out by the volunteers who have worked on this project since it began, along with the recent addition of Jess, a very able abseiler and Chloe, who now rings any chicks for us.

It could be that our web cams will be down for a while during the work, but our priority has to be the nest box for the birds, rather than cameras for all our viewers. Rest assured we will keep you updated as and when we have news we can share.

Here's Nick Moyes' mock up of the new temporary box:

The box itself is designed to be set back slightly from the parapet to minimise its visual impact when viewed from the street below the Grade1 listed building.

A floor and side panels will link the box to the stonework, and will both prevent the birds inside from seeing people on the roof and visa versa. They will also prevent any chicks falling onto the roof. No drilling or other damage to the stonework will occur, of course. The back will be hinged and kept locked, but openable for ringing and maintenance. Having a box that doesn't require an abseil to reach it would make life so much easier! 

We are confident that the few very occasional visits by cathedral staff (eg to change the flags) will not disturb any incubating or brooding female inside the box if carried out quietly and quickly. There will be no public tower tours until the major renovation work to the roof is carried out towards the end of 2026.

Meanwhile, here's a video made by Wendy Barrter on 30th January showing the new pair bonding well. As you can see, any egg laid there now would simply roll away!

Finally, we hope to be able to install a camera inside the box in due course so that we can all see what's happening inside it.

If you would like to donate to support the work of the Peregrine Project, please use the 'Donate' tab, or click here.

The Peregrine Project Team 
This project is managed by Derbyshire Wildlife Trust with great support from The Cathedral and from the City Council's IT team.