Mid Nene Local RSPB Group helping Swift nesting

The inspiration.

The Mid-Nene Local RSPB Group had a talk about Swifts by Laurinda Luffman of the RSPB in January 2023. Lurinda’s talk covered the rapid decline in Swift numbers and the work local Swift groups were doing by putting up nest boxes. There was a lot of interest from our members, particularly about what they could do to help and about Swift nest boxes. After that, I asked if the group would support a local Swift group and use some of the money that we raise to put Swift boxes in local churches. The group were supportive and that was that!

The plan.

Following some visits to measure up the belfries of some churches in the autumn of 2023, the construction of nest boxes began in earnest in early 2024. With Swifts being long-lived birds and the possibility that it could take a few years for them to take up residence in the nestboxes, it was decided to build the nestboxes to last. The nest boxes were built using marine plywood and all the joints were glued and pinned. For extra protection, they were all given three coats of fence preservative. This may sound a little extreme for nestboxes installed inside belfries but, whilst installing some nest boxes in the church of St Nicholas at Overstone, a squally shower demonstrated that rain can be blown through the louvred windows and half way across the belfry floor.

Nest boxes

 Swifts collect their nesting material on the wing, by catching feathers and pieces of grass blowing in the wind. The nesting material is then glued together using their saliva. This makes nest building a very time-consuming process. To give them a head start, all the nestboxes were fitted with nest concaves, which also ensured they had a nice sturdy cup in which to lay their eggs. These were constructed using squares of plywood, of varying thicknesses, with concentric holes of different sizes. Once glued together, they provided a cup-shaped profile with a vertical rim to prevent eggs rolling out.

The nestboxes were also designed to ensure that their use could be monitored. The internal nestboxes were constructed with opening panels on the back, and the external nestboxes were fitted with opening lids.

Participating churches.

So far, nestboxes have been fitted inside the belfries of St Johns Church at Cranford, All Saints Church at Mears Ashby, St Peters and St Pauls Church at Sywell, St Nicholas Church at Overstone and St Laurence Church at Stanwick. Four nest boxes have been installed in each of these churches.

Visiting the church belfries has been quite an adventure and most enlightening. They all posed their own obstacles and challenges. Whilst some were quite easily accessible via spiral staircases, even if they were somewhat worn, some involved climbing very steep ladders and hoisting the nestboxes up using the bell ropes. 

Installation

The favoured way of installing them was to make them the width of the windows and screw them into the side frames of the louvres. This removed any need to drill and screw into the masonry or mortar; making it much easier to obtain permission to proceed from the Archdeacon. However, this requires careful measurement of the windows as the masonry can be a little irregular. Whilst the church at Overstone had a nice wooden floor beneath the bells, for others, gaining access to the windows involved squeezing past or climbing over the bells, whilst walking on the steel girders that supported them. This was quite an adventure, if a little dirty and dusty on occasion. For some, the side frames of the louvres were quite wide, allowing some leeway for inaccurate measurements, but for others there was little room for mistakes.

St Nicholas Church at Overstone was also different in that there were no side frames to the louvres. Instead, they were set straight into the masonry. Not wanting to drill into the fabric of the church a little thought was required to come up with an alternative method. Fortunately, a very sturdy mesh was fitted behind the louvres to exclude pigeons and other large birds from the belfry. Eventually, the decision was taken to attach the nest boxes to the mesh using heavy duty cable ties.

All of the churches were fitted with some sort of mesh or barrier on the windows to exclude Feral Pigeons and Jackdaws. Holes had to be carefully cut into the mesh to align with the entrance holes of the nest boxes. In the case of the church at Overstone this required the use of a small pair of bolt croppers. The one exception to this, has been St Laurence’s Church at Stanwick, which has wooden weather/sound proofing boards behind the windows. In this case, rectangular holes were cut in the boards using a drill and jigsaw, taking care not to drop the offcuts on anyone below in the churchyard. It was then simply a case of screwing the nest boxes to the weather boarding, without the need to touch any of the original parts of the church.

The width of the windows was found to vary quite a bit. At Mears Ashby there were two windows on each side of the belfry, each wide enough for single nestboxes. However, the windows in most of the churches were wide enough to fit double nestboxes side-by-side.

We have also put up two external Swift nest boxes at the United Reform church at Brigstock. They were keen to have some nestboxes, but did not have a belfry.

However, being a United Reform Church made it a lot easier to get permission to attach them to the outside of the church. However, I was still a little reluctant to drill into the old crumbly mortar. Fortunately, whilst looking around the church for possible places to attach them, we spotted an old oak beam embedded high up in the wall. Screwing them to the beam provided an ideal opportunity to install two nest boxes without risking any damage to a listed building. 

Other Wildlife

One thing that all these old, undisturbed buildings have had in common has been the amount of wildlife that they support. They have all had large quantities of hibernating Harlequin Ladybirds as well as a few species of hibernating butterfly; mostly Small Tortoiseshell and Peacock. Of course, as you would expect with belfries, there was also evidence of bats, but none were seen or disturbed during our visits. Some of the parish councils are also very proud of the wildflowers they have growing in the churchyard, the Swallows nesting in the entrance porches and even the Badgers burrowing under the fences. There has also been some interest in putting up more nest boxes in some of the churchyards for Blue and Great Tits, Robins and maybe even Tawny Owls. Sounds like an opportunity to take this work a whole lot further.

Throughout the summer, we have played the calls of Swifts from the belfries to help attract them to the nestboxes. Unfortunately, there are no signs that the Swifts have found the nestboxes yet. However, we started playing the calls a little late this year due to delays in collecting sufficient old phones and unwanted MP3 players to play the calls. It can also take a few years for Swifts to take up new nest sites, so we will have to be patient and keep our fingers crossed for next year.

Going forward

There are also more churches showing an interest in Swift nest boxes, including those at Raunds, Easton Maudit, and possibly Ringstead and Grafton Underwood. It looks like the adventure is likely to continue with more ladders, ropes and bells to negotiate, and more installation challenges to overcome.

This has all been possible thanks to the support of funds raised by our group, which have been used to supply most of the materials used in the construction of the nestboxes.

The above article was written by Dr. Ian Wrisdale, a senior member of Northants Ringing Group. Ian is the lead ringer at Stanwick Lakes Nature Reserve and also Chair of the Nene Valley Local RSPB Group.