An eye on the details (of the eyrie)

‘Was wondering today whether anyone would be interested in some of the more technical aspects of this season’s replacement box. Too late – ‘telling you! We decided we’d learnt so much from the first 18 months in the project, in terms of what we needed to improve, what the birds needed to be more comfortable, that we were ready to step up to the next level.

The original box was designed by Ian and Cilla using suggested falcon recommendations. It served its purpose and provided amazing results as well as fitting in well with the peregrine’s requirements for a roost. Proof was in our first 2 season’s data. In saying this we also learnt how to improve version 1.0. Primarily we went for improved camera angles and much more space – with 3 chicks in a box 330mm (13inches) deep by 780mm (30inches) long there was little peace. The timber used was a particle board and had started to soften with repeated wet days/weeks/months.

The box v2.0 was radically different. We used thick waterproof plywood for longevity. All screws, hinges and fittings are in brass to lessen toxicity to birds (often a problem using galvanising or plated objects). We’ve deepened to about 600mm (24inches) with a similar length and height. The base is multilayered, with lots of drains holes covered in brass mesh, topped by a layer of simple rubber mat with large holes to stabilise the layer of new rounded pea gravel to 60mm (2.5 inches). This has prevented gravel being scraped right down to the wood but provides a stable surface to roost and incubate on.

We learnt that no matter where we put camera & viewing holes the chick/s would certainly find them and rest against them, blocking views. We also learnt the nominal “poo line” height (which meant we could be inside the box every day cleaning windows, even with terrified chicks in residence – not clever). We added angled ends below the much larger and higher-set viewing windows to keep the birds off the windows and to aid camera focussing. Each end also doubles as a full length opening hatch, with camera fitted to a ledge so it doesn’t get in the way when we have to open up. End hatches also mean less chance of losing a chick over the edge when backing away from us when banding begins.  The non-camera’d end has a large black rubber cover which can be lifted silently when using it for viewing or extra camera. Each end hatch has a brass latch that can be simply locked when needing to use both hands inside the box for the likes of banding or maintenance. A smaller maintenance/camera hatch sits on the back wall and won’t be used.

Design and preparation involved 6 weeks of paperwork, models and some spent brain cells. We managed to construct it down on the ground, but the design allowed us to cut it down into a series of much smaller sections which would allow us to hike it up the 50m (165ft)  of extremely narrow tower steps, crawling under pipes and not looking back down the middle. Another consideration was to be able to re-assemble in very minimum time, in case we were not alone! The box was indeed rebuilt inside of 8–10 minutes, and with little hassle for Swift who wouldn’t leave us alone.

We carted and rebuilt the box but not before Swift had laid her three 2nd season eggs early so we fitted 2 very large wall brackets underneath the old box in readiness for the extra weight (during a break by Swift). Again, done by Ron inside of maybe 4–5 minutes. We elected to keep the box on the tower floor in case we could obtain new cameras – MUCH easier to mount on the box whilst on the floor than when 2.5 metres up the side of a wall. They didn’t arrive and so just days before Swift’s 3rd season cluster we press-ganged the Facilities worker elves into a  nice leisurely climb, and with plenty of pre-planned choreography & effort by Chris and Ron (by now the internals and gravel had been fitted, effectively doubling the weight) the swap was done inside of 2 mins 10 seconds! Awesome effort, guys!

Now we’re able to maintain cameras without intruding, get really good access once the banding operation begins (should be next season), and the peregrines have plenty of undisturbed room for up to 4 occupants. We’ll no doubt keep learning and improving.

And that, in the world’s largest nutshell, is the story behind the box. If anyone would like to know more about the physical box, or techniques etc just email us or leave a comment.

Scott