Friday 20 November 2015

Maurice Wilkinson's nest boxes

Maurice Wilkinson has been attracting Swifts and House Martins to his house in Needingworth since 2010. He has a number of innovative ideas which are worth sharing, including the use of uPVC as a material, and simulated eaves for House Martins.  It is a good example of how to grow a Swift and House Martin population in a rural village, estimated at 3 pairs of Swifts in 2009 to an expanding population which has reached 8 pairs in 2015 together with 15 pairs of House Martins.

A  DIY uPVC box and 3 Schwegler 17's
Maurice started attracting swifts into Schwegler 17 nest boxes in 2010, after a single bird was seen trying to regularly access a House Martin nest the previous year. Calls were played each summer. Swifts subsequently visited, with first breeding in 2014.

He then started to make his own boxes out of 9mm uPVC, normally used for fascias and soffits.

Occupied artificial House Martin
Nests under normal eaves
uPVC is an ideal material as it has good thermal properties, it reflects sunlight, is waterproof, indeed, it is designed to resist all weathers.

Maurice's boxes have a plywood floor, which gives some absorbency.

In 2015, Maurice had 2 pairs of Swifts, in his own-designed nest boxes, as well as 1 pair in a Schwegler box. 2 more pairs took up residence during the summer in Schweglers, building nests, with several birds investigating other boxes.

Occupied artificial House Martin 
nests under simulated eaves
Maurice has also attracted House Martins into artificial nests under his eaves, as well as under simulated eaves on his gable end. In 2015 he had 17 occupied House Martins nests, the highest number to date.

The simulated eaves are also made of uPVC, so they should have a long life. 

An artificial House Martin 
nest beneath a uPVC Swift box
Plywood exposed to the elements eventually deteriorates. There is a case for plywood boxes, which are exposed, to be given a uPVC roof.

Maurice fitted a uPVC double box on his neighbour's house and another near neighbour has put up 2 of John Stimpson's Zeist boxes, with another 2 to be put up this winter.

This autumn he has added more Schweglers and uPVC boxes, making a total of 29 Swift homes on his house. 

There are now 23 artificial House Martin nests plus 5 naturally built nests on Maurice's house.

Friday 13 November 2015

Owlstone Road, Newnham, Cambridge

In 2011,  we installed two 4-box Swift cabinets on 2 houses in Owlstone Road, Newnham. As in many places over the years, a street with a vibrant Swift population had been reduced to virtually nothing. The first Swifts probably occupied the cabinet on Pam and Vic Gatrell's house in 2014, but they were away for much of the summer, however in 2015, 2 pairs were definitely in residence, and one of them raised 2 chicks. 

by Dick

Two chicks looking out of the cabinet. Photo Vic Gatrell
Not being satisfied with this, Pam and Vic wanted more boxes. While we could have suggested a second cabinet, instead, we took a good look at the structure of the gable end, and suggested built-in boxes.  

The gable wall is 2 bricks thick, with no cavity and is built in Flemish bond: a sequence of headers and stretchers. Removal of a header makes a hole all the way through the wall. This was relatively easy, as the bonding was soft lime mortar.

Two entrance pieces and their moulds
With previous experience of retrofitting entrances fabricated out of airbrick liners, (here and here), this time we decided to try something different, with entrances cast in a mould using a 50:50 cement/sand mixture. 

The mould was made on a 3D printer. This meant the hole could be made to a fine tolerance, with dimensions 65mm x 29mm on the inside and 68mm x 32mm on the outside. Thus it was slightly tapered, allowing easy extraction from the mould and any rain drops would tend to flow out rather than in.

Casting entrances in a mould is a lot easier than slicing up airbrick liners.

Pam and Vic own the part of the wall
left of centre. Photo Pam Gatrell
Apart from manufacturing the entrances, the only other thing we did was to build the first nest box. We then handed over to Newnham Property Services who fitted all 6 entrances in the wall, built the remaining 5 boxes and fitted them inside the roof-space.

The work also included making a trap-door from an upstairs bedroom into the roof-space.

The end result is very pleasing, and bodes well for the return of a thriving Swift colony in Owlstone Road.

The following pictures should be self-explanatory.

[For Newnham Property Services, contact Marek on phone 0773 137 6154]
6 new entrances; the natural colour of the cement/sand mixture
matches the brick colour remartkably well. Photo Pam Gatrell

Design drawing for the nest boxes. All boxes are fitted with a perspex back.
The perspex is held in place with slots top and bottom and slides out sideways

6 boxes inside the roof-space. Photo Pam Gatrell
#inserts #Cambridge