Thursday 26 March 2015

Eaves nest box design tool

We have built quite a few Swift nest boxes to fit under broad eaves. Some eaves are horizontal and some slope at an angle. The angle and width of the eaves varies. Every time I generate a new drawing, so I decided to see if one could produce a generalised template. This is not for those allergic to spreadsheets or for technical Luddites, but it may have some mileage for those who can overcome these psychological barriers.

Contributed by Dick

The great thing about boxes under eaves is that they are largely sheltered from the weather. So plywood is a suitable material and it is ideally suited to those with a DIY bent. The generic design proposed here looks neat under eaves. The carpentry is not that challenging. It doesn't cover all eaves situations, but it is ideal for broad flat horizontal or gently sloping eaves. (slope less than 30° say).

Ideally one needs a parametric CAD system for these sorts of things, but they are expensive, so, we have encapsulated the design in a spreadsheet which calculates all of the necessary dimensions from a few parameters provided by the user.

You can see the spreadsheet here then download for use in Excel.

Designs resulting from 3 parameter settings

Dimensioned design drawing

Thursday 19 March 2015

More Swift boxes in St Neots church

In 2007, we installed 12 Swift boxes in the north side of the belfry of St Mary the Virgin, St Neots. Most years, attraction calls have been played and in 2014, 9 of the 12 boxes were occupied. With the help of generous funding from 'St Neots in Bloom' we have now added 32 more boxes, 16 in the east and 16 in the west.

[Update July 2015: 2 pairs occupied the new boxes on both the east and west sides and the occupied boxes in the north increased from 9 to 10 pairs]
[Update 2019/2020 We have added another 16 boxes in the north, bringing the total to 60 boxes of which 40 were occupied in 2020]

by Dick

West side of belfry, the boxes are just
visible half way up the louvres
The louvres in this church are enormous, and it was not possible to follow our usual advice of putting boxes behind the highest louvres first. We therefore went for putting boxes behind the openings half way up. Even so, it was quite a feat of engineering to erect boxes 15 feet above the floor of the belfry. We thought that entrances here would be more obvious to the Swifts compared to entrances behind the louvres.

We had 2 choices for the colour of the boxes, black or stone. We chose stone (Sandtex 'Mid Stone') to provide a better contrast for the entrances. Whether this contributed to the success of the first 12 boxes we cannot say, but it worked.

Battens were affixed to the stonework each side of the louvres, by screwing into the soft mortar. No holes were drilled in the stonework. The boxes are secured to these battens.

8 of the 16 entrances on the west side.
The original 2 cabinets contained 6 boxes each. This was done at a time when we thought that Swifts required a larger space. Since we have discovered that Swifts readily accept smaller boxes, we increased the number of boxes to 8 per cabinet, we could not have got any more entrances in the limited size of the openings in the stonework. The floor area of each nest box is 20cm x 29cm.

4 completed cabinets, ready for installation
The inspection doors of the earlier cabinets were a simple flap rotating about a single screw. This wouldn't have worked in the new cabinets because the flaps would have collided, so we went for a simple hinge and a catch.

Many people contributed to this phase of the project, not least, Alison Pearson of St Neots in Bloom with their generous funding and encouragement, but also Jake Allsop, Bill Murrells, Bruce Martin, Bob Tonks, Judith Wakelam, Alan Clarke, grandchildren Katie, Lucy and Benjamin Thompson (who got paint all over his shirt). Lastly, we would like to thank the Vicar, the Reverand Dr Paul Andrews, and PCC for their permission to do this project as well as Catherina Griffiths, David Griffiths and George Bonham for their help with access to the church.

We hope that residents and visitors to St Neots will enjoy a magnificent Swift spectacle for years to come.
The original cabinets on the north side installed in 2007
New cabinets on the west side installed in 2015.
The cabinets on the east side are similar

Friday 6 March 2015

Swift Conservation at Ecobuild

On 5th March, I had the pleasure of spending a day with Edward Mayer on Swift Conservation's exhibition stand at Ecobuild. 

Contributed by Dick

Held at the Excel, Ecobuild is the world's biggest sustainability event for the built environment, with roughly 800 exhibitors. It has everyone from those making money out of climate change, to recycling, houses made of straw, specialists in Japanese knotweed and those interested in the environment. Swift Conservation was one of a suite of stands in the 'Biodiversity Pavilion' alongside the Bat Conservation Trust,  British Beekeepers Association, Buglife, RSPB, Woodland Trust and NBN.

It was a great opportunity to talk to many people in the building industry about what they can do to reverse the decline of Swifts. Winning the hearts and minds of this industry is key to getting something done.

Eventually all of the UK Swift population will be in nestboxes, after every roof, eave and wall has been repaired. it will be like the situation with Purple Martins and Eastern Bluebirds in the US where the whole population now breeds in nestboxes.

The only way that the hundreds of thousands of nestboxes needed can be installed is to get the building industry on board. Ecobuild is a great opportunity to get at some of them.