Saturday 2 February 2013

New Swift boxes in Oostvoorne

We saw this heartening story on Norman Deans van Swelm's website, and we thought it worth re-blogging here. A large colony of Swifts in Oostvoorne lost their nests due to roof renovation. However, thanks to an initiative by local citizens, the colony was saved. We also thought that the nest box design was neat and simple, and fitted in well with the houses.

Contributed by Norman Deans van Swelm, adapted by Dick

As in many other places, Swifts, House Sparrows, Starlings, Bats and House Martins all lose out when modern roof renovations conform to government regulations, where, in the Netherlands, all roofs must be delivered "mouse free".

However, as the nests of Swifts are protected by law, the village council provided funds for nest boxes to compensate for the loss of nest-sites.  The nest boxes were designed by Martin van de Reep so that the new entrances could be as close as possible to the old entrances.

Roughly 80% of the 168 boxes installed in 2011 were visited by Swifts that same year. Originally, many of the Swifts entered the roof at the end of the gutter. Others accessed their nests via an entrance next to the rain pipes. It took a while before the birds realised that the former entrance had been blocked by a nest box.

Initially there were quite a few fights between pairs competing for the same nest box.

In 2012, 130 young were ringed.

Also in 2012, House Martins took advantage of the new nest boxes provided. They only needed to use a fraction of the amount of mud that they normally use to reduce the size of the entrance

The previous entrance was behind the pipe. This Swift has successfully found the new entrance.

The new nest boxes do not detract from the appearance of the houses

This is a rather nice outcome

The boxes made were 400mm deep, which is wider than many people's eaves. The material used was Western Red Cedar with stainless steel screws. As these boxes will never be exposed to the sun or rain, then any treated material should last a long time.

Below we have modelled a similar box in Google Sketchup, with indicative minimum dimensions. Ideally, this box needs eaves at least 250mm (~10 inches) wide. We have modified the Oostvoorne design slightly, by extending the front up a small amount, so that it is easier to fit snug under the eaves. If you have more space, then make the box deeper and wider. The whole front can be removed for inspection.

These minimum dimensions are for guidance. One would not want less than 250mm for the depth.
The length could be made longer than 300mm.

Internal structure

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