Saturday, 26 May 2018

Swift boxes in an 18th century brick wall

Helen Copperthwaite of Millgate, Aylsham, Norfolk lives in an 18th century maltings, with walls 1.5 bricks thick. (~350mm). At least that's what we thought when we started. She was keen to have Swifts nesting in her gable - so being something new, we decided to have a go at it.

Helen kindly laid on a cherry picker, as it may not have been sensible to work all day on ladders at that height.

Our idea was to remove a header and stretcher from the outer wall, then drill out any brick remaining in the middle producing a cavity 350mm long and 85mm high leaving a half brick between the nesting place and the room inside.

We would then cut a 40mm wide piece off the outer stretcher, replace the header with a Cambridge System half brick entrance piece and we would end up with a very nice internal nest space 350mm x 185mm x 85mm.

Where the wall was 1.5 bricks thick this went very well according to plan:

Stretcher, header and bricks in centre of wall removed
Nest concave inserted - bedded down in mortar
Bill Murrells pointing up the inserted components
Sliced stretcher and entrance piece mortared in.
The mortar will dry to a good match with the old mortar
However, unknown to us, in some parts of the wall, the inner bricks had been removed and replaced by studs (timber) and insulation, so we had a wall  only 1-brick thick (~225mm). However, in the places that we broke through to the insulation there was always a stud against the wall. So we screwed a rectangular piece of plywood to the stud, completely blocking any access to the insulation, leaving a nest space 350mm x 175mm x 85mm, similar to the space above. We think this is a viable solution to any wall that is just 1 brick thick.

The final result was 5 new nest places:

5 new internal boxes embedded in the wall.
To demonstrate the principle of how we fitted boxes in the 1-brick thick parts of the wall, these illustrations might help.

Outside view
Inside view
#Cambridge

Thursday, 24 May 2018

Queen Anne Car Park Cambridge

We were asked by Guy Belcher of Cambridge City Council to dream up something for Queen Anne car park. It should be a good location, in central Cambridge, overlooking Parkers Piece. The location is high, but accessible from above The walls were not suitable for attaching anything directly to them.

So we came up with the idea of a 'Stretched Model 30' - 6 chambers in each of 2 long colony boxes. It was important that the boxes were beyond the reach of vandals with long arms, so to secure it, we designed 2 brackets to hang from the top of the wall.

The two boxes came from just 1 sheet of plywood 2440mm x 1220mm plus a bit more for the ends and internal partitions. The roof and ends are both covered in 9mm PVC fascia board, none of the plywood is exposed to sun or rain. The plywood back is well ventilated.

This installation took a lot less work than installing 12 single boxes.

Arrival at the top of the car park
Assembling the cabinets to the brackets
The boxes are positioned to avoid entrances vertically aligned. Photo Alan Clarke
Ready for installation
Final installation

Computer views inside and outside the wall
Addendum:
Using the same design, but different fixings Colin Wilson arranged for 2 Stretched Model 30's to be installed on Camberley Theatre in the borough of Surrey Heath. Two more are to be installed on a local shopping centre:

Photo Colin Wilson

#parapet

Wednesday, 23 May 2018

Swift boxes under very broad open eaves

Margaret & Ian Hobson of Beer in Devon asked asked us what would go best under broad open eaves, nearly 50cm wide, with about 33cm between the joists.


Beautiful view of the English Channel
Click to enlarge
The first idea was to have 2 boxes between each pair of joists with the entrances near the wall or near the outer edge. However, as we have no idea which the Swifts may prefer, we came up with a design for a double box between each pair of joists with one entrance near the wall and another near the outer edge.

We chose to give the entrance near the wall a landing platform, for no better reason than, in our experience, we have had more success with entrances near the wall with a landing platform than those without, but not enough evidence to be definitive. The landing platforms are grooved by making shallow horizontal cuts with a mitre saw.

The outer entrances face down at 45°. There are plenty of examples of success with sloping entrances e.g. the Zeist and Model 30 boxes.

As this was a new idea, we decided to have a go at it ourselves, and we then shipped the boxes flat-packed to their destination in Devon, where they were competently reassembled.

The boxes are installed by removing the bottom, screwing the sides to the joists, then replacing the bottom.

Preassembled box - landing platform on the right.
The bottom is configured so it is easily removed for installation.
It also provides a small step for the Swifts.

View prom above - 2 nice-sized chambers

Boxes reassembled, painted, concave glued down and feathered, ready for installation
4 double boxes installed

#openeaves







Sunday, 20 May 2018

Lymington Business Centre. creating a Safe Environment for Swifts

Thank you to Nick Windibank and Andy Broadhurst of Hampshire Swifts for sending us this story.

Lymington Business Centre
Lymington Business Centre occupies a building which was renovated in 1986 from its original use as a squash club. It consists of three storeys, the top level being of a wooden frame construction which has eaves on two sides with protruding rafters and is clad in slate.

The building is known to us due to its association with what are known locally as the “library Swifts” which form large groups over and above the nearby library but which we now know nest in some of the gaps above the slate cladding on the Business Centre. 

Slates showing where a Swift was trapped
In the winter of 2017 it was noted that there was what seemed to be nest material adhering to some of the slates and this was investigated as there was concern Swifts could get entangled.

It quickly became apparent that this material was in fact the corpses of two Swifts and a Starling, which had the misfortune to get trapped in the vertical gaps between some of the slates. We subsequently found out that a nearby resident had called the fire brigade on one occasion to free a bird caught in this way.

Having the opportunity to examine the spaces between the rafters we determined that additional nest sites could easily be created by attaching mounting bars to each rafter and then screwing a horizontal sheet to create the base of a nest site.


An example of 2 exposed rafters
showing the potential to create a nest site
Each sheet would have a nest hole and then be painted to match the rafters so rendering the whole assembly virtually invisible to passers-by. The original plan was to survey the two eaves in the summer of 2018 to determine which gaps already had Swifts nesting in them and then, during the close season, create new nest sites in the spaces not already used by Swifts or other species.

Examples of nest sites created between rafters
Concerned about the possibility that more Swifts would get trapped in 2018 we brought forward the plan, relying on the man on the ladder to determine whether or not there were gaps in the structure which could be used by Swifts. If not, then they were converted to new design Swift nesting sites. If so, they were left.

In this way 18 gaps on the rear aspect and 10 on the side aspect were converted to new nest sites, complementing those already present. At the same time all the gaps between the slates were sealed making it impossible for birds to get trapped in future.

To avoid disturbance to the tenants of the Business Centre, work could only proceed at weekends and in the evening and so progress was slow, especially on the side aspect when scaffolding was required to gain access to theeaves. The final nest site was created on the 7th May and birds were already entering some of the retained original nest sites.

This summer we will check out the occupancy of the remaining potential sites to determine what the baseline occupancy is, in the hope that in future years this building will develop into a major colony.

Thanks are due to Don Mackenzie, the owner of the Business Centre who enthusiastically supported this work and made a significant contribution towards our costs, Tim Norriss who designed the nest sites and Roger Maynard, roofer extraordinaire who actually did the work come rain or shine. Thanks are also due to Waitrose Lymington branch which, through their Community Matters scheme, raised a total of £ 451 for this project.

#openeaves




Friday, 18 May 2018

Trumpington Meadows Nature Reserve

Trumpington Meadows is a spacious expanse of flowering meadows, riverside, woodland, hedgerow and parkland. 

According to their website:


"... this expansive nature reserve and country park sits alongside the River Cam and Byron’s Pool Local Nature Reserve, straddling both sides of the M11. Created for wildlife and for people, it is a place to discover and enjoy nature, explore diverse habitats and wander by the river and through flower-filled meadows. There is a Wildlife Trust office and garden, allotments, and a range of interpretation features and hand-carved nature sculptures throughout the site. "

Trumpington Meadows is managed by Beds, Cambs and Northants Wildlife Trust

Action for Swifts was approached to see if it might be possible to increase the biodiversity of the site by installing nest boxes for Swifts. Initially, a Swift Tower was considered, but given that the offices on site included a high gable, it was decided to build a 10-box triangle colony box instead.

At the same time, in the year of Swift Awareness Week, Nature Picture Library was looking for a Swift project suitable for sponsorship. So what better, a high profile location on the outskirts of Cambridge with an ideal building for installing Swift boxes, and a benefactor looking for a Swift project to support.

Nature Picture Library makes a regular contribution to a small charity or specific project which is making a difference. They choose a different charity every three months. You can read about them here: https://www.naturepl.com/about-us and about some of the projects that they have supported here: https://www.naturepl.com/conservation

AfS has previously implemented triangular colony boxes containing 3, 5, 6 and 9 nesting chambers. With its shallow roof (30°), we decided to go for 10 nest chambers this time. It is a proven concept as most implementations so far have nesting Swifts.

We used this project as an opportunity to progress our attempts to determine whether Swifts prefer a dark or light interior. Half of the boxes are painted black inside.

Having carefully assessed the risks and devised a safe method of work, the body of the cabinet, weighing nearly 20kg, was installed by 3 people lifting it up 3 ladders. The central ladder had a reinforced standoff platform, which was raised every time the cabinet was raised. Finally, the middle person climbed the middle ladder to put the screws in while the 2 on the sides held it in place. The screws were carefully positioned in line with the internal timbers Then the front was screwed on. It all went very smoothly. 

A camera is installed in the top chamber, as this is the most likely to be occupied first, and all of the other chambers have been prepared for cameras if and when Swifts move into them. A tweeter for attraction calls is installed out of the weather under the box.

[At the time of writing, Swifts have already been seen approaching the boxes]

Front removed, ready for installation. Half the nest chambers are painted black.

A good height in a northerly facing aspect
Frontal view
Oblique view

Tweeter, installed out of the weather, and the AV cable.

[UPDATE June 2018: Swifts have been seen entering the bottom left box and the middle box]

#triangle

Monday, 7 May 2018

The boys are back in town!




John Day was inspired today when the first Swifts showed up in Potton - on schedule on 7th May. So he decided to parody Thin LIzzy's song, "the boys are back in town" with the following lyrics:






"Guess who just got back today
Them wild-eyed swifts that had been away
Haven't changed that much to say
But man, I still think them swifts are crazy
They were askin' if their nests were around
How they was, where they could be found
Told 'em there were some still downtown
That haven't been blocked up today
The swifts are back in town
(The swifts are back in town)...... "

Thank you John! It captures the moment perfectly.

Friday, 4 May 2018

Successful Project with a Derbyshire school and housing agency

This is a good story in the year of Swift Awareness Week
by Nick Brown

Last autumn a meeting was arranged by the Derbyshire Swift Conservation Project with Rykneld Homes with additional support from Derbyshire Wildlife Trust. Rykneld manages the social housing for NE Derbyshire District Council.

An Ibstock Swift brick
While most of their work is maintaining the 8000 houses they have already, occasionally they build new properties. Jude Milburn, Rykneld’s Community Involvement Officer, attended the meeting and took up the Swift cause. Liaising closely with us, he worked to get internal Swift boxes put in nine of the 50 houses in a new social housing development in North Wingfield, close to the village school (with some bat boxes in addition).

He also arranged for the Project to meet Rachael Peacock, the head teacher at the newly built village school. We explained how Swifts would make a great learning topic for the children – an idea she embraced enthusiastically. In addition, Jude gave her six Swift boxes to put up on the school. On 20th April, Rykneld organised a small ceremony to mark the completion of the new houses.

Swift boxes in 6 country colours
On a lovely sunny afternoon, thirty children from the school joined in by painting their six boxes in the colours of the flags of some of the countries the birds fly over on migration to and from Africa (Spain, Morocco, Ghana etc). This novel idea was first dreamed up by Ian Carstairs in Harleston, Norfolk so we can’t claim it as our own!

The children worked enthusiastically and the boxes will be put up on the school as soon as possible.

There are Swifts nesting in the village and we hope Rachael will be able to get the children to ask their parents if they know where, prior to us doing some survey work in the summer.

In addition, some of the children from the school will be moving into the new houses. Should they move into the ones with Swift boxes, Jude will ensure that they are made aware of their boxes and the reasons they were installed. Ideally we hope Jude will be able to engage with all the new tenants and to that end we will be providing him with copies of the new AfS leaflet and booklet to hand out.

Engaging the next generation

Job done!


Wednesday, 2 May 2018

Swift boxes in a rendered cavity wall

In a rendered wall, one cannot see the brick structure, so doing a neat job, as in the Cambridge System, is not an option.

[See update at the bottom of this post where we re-engineered the entrances]

Christina Day had 9 Swift boxes in the gable of her house in Haverhill (see here). Circumstances conspired so that she had to move to Lode, leaving four occupied boxes behind. Her new home is a one storey house on the end of a terrace with a gable 6 metres high.

So we inserted 6 boxes in her gable by using a 78mm diameter core drill (acquired from Screwfix) through the render and outer leaf and a 107mm core drill through the inner leaf. The entrance was reduced with mortar to a half-moon 30mm high, with a ramp across the width of the outer leaf.

The 50mm cavity is bridged with a 100mm pipe.

The risks in this project were that we could have hit a wall tie, or the render could have been laid on steel mesh - but fortunately we encountered neither of these.

We did not anticipate that the bricks in the outer leaf would have a 'frog' facing down, leaving holes in the entrance passage which needed making good ('frog' = a depression made in a brick). Nor did we anticipate the state of the inner leaf, with much of the mortar loose, needing substantial repointing.


6 neat holes in the gable
6 installed Swift boxes with a satisfied Bill Murrells
Close up of entrance exterior
Close up of entrance interior
Installed Swift box, with perspex back and cover removed.

Section through computer model
Tool used to fashion entrances

UPDATE September 2018

We are pleased to report that one pair moved in to one of the boxes, laid 2 eggs and hatched 2 chicks. However, we had second thoughts about the entrances after the chicks fell out and were then replaced in the box.

We realised that any chick venturing as far as the conical tunnel entrance would not then be able to reverse back into the box. so it was decided to re-engineer the entrances. This was achieved by drilling a rectangle of small holes around the circular entrance and then inserting a half-brick entrance piece. For this project we used up some entrance pieces made from sections of air brick liner as described here.

A further problem was that, in the long hot summer, the temperature in the roof space reached 42°C, so the chicks were taken into rehab and were successfully fostered by Judith Wakelam. The plan is to install ventilation tiles in the ridge of the roof.

Finally, on inspecting the boxes at the end of the season, 2 other boxes had feathers stuck down to the nest forms, so maybe more pairs will materialise next year. 

6 re-engineered entrances

Close-up of re-engineered entrance