Swift nest boxing results in Cambs & Suffolk

Written by Dick

As there is not much Swift activity around right now, we thought it might be worth reviewing the results that have been achieved with Swift nest-boxing projects. Most of these have been in Cambridgeshire, with a small number in Suffolk, the county next door.

The table below summarises the results in 2012, though in many of the sites, first occupancy was in a previous year:

Breakdown of Swift nest boxing projects.
The figures are for boxes available before or during 2012.

The large majority of these projects were installed in 2010 or later.

We have explored 2 factors which might influence success rates, first the playing of attraction calls and second whether the project could be regarded as mitigation for nest sites recently lost in the near vicinity.

Although only 13% of boxes are occupied, this figure is influenced by a small number of projects with a large number of boxes, some of which only have a few boxes occupied so far e.g. "The Swifts", Fulbourn (157 boxes, 27 occupied), Edgecombe flats (71 boxes,  2 occupied), St Mary's Church, Ely (96 boxes, 21 occupied plus 11 possibly occupied with some feathers) and the Cambridge Swift Tower (100 boxes, none occupied). Hopefully, over time, these will achieve their full potential. However, 104 new pairs of nesting Swifts is something to be pleased about.

We are encouraged by the number of sites with at least 1 pair of Swifts: 38% of all sites. Of these, those where attraction calls were played, there was a 43% success rate. Those where nest sites had been lost nearby had success in 5 out of 6 projects.  It turns out there were no sites where both factors apply.

If one combines the sites where there was some attracting factor, then 20 out of 41 sites (49%) were successful. The 12 sites with no attracting factor had no success whatsoever.

Car batteries and solar panels

[We have now consolidated everything on attraction calls on this page]

There are some situations where there is no mains power, in which case, the only alternative is a battery, possibly backed up with a solar panel.

Contributed by Dick

There are commercially available bird call systems to solve this problem, for example based upon the Martley Electronics Bird Scarer and the Spark4 Birdsong Player. There is nothing wrong with these systems, except they are probably overkill for a Swift attraction call player, and cost more than you might wish to pay.

We have been exploring the use of a solar panel to recharge a car battery which then powers a Cheng Sheng player amplifier system. At maximum volume, it consumes half an amp at 12 volts (6 watts). At a more reasonable volume it consumes about 0.3 amps (~4watts).

Thus, a car battery of, say, 45 amp-hours could provide 150 hours of continuous running before the battery becomes flat. It is probably not a good idea to run a battery completely flat. However using half its capacity would provide 75 hours. At 4 hours per day, it would run for nearly 19 days.

Such an approach might be workable, recharging the battery every 19 days, longer if you use a bigger battery. This is barely practical if the battery is in a remote location, such as the top of a church belfry (we've tried it), in which case the addition of a solar panel should be considered.

Schematic showing component connections

As the Cheng Sheng player amp consumes up to 6 watts, we bought a 20 watt xm solar panel (costing £30) and a Morningstar SunGuard 4.5A solar regulator (costing £28) from Midsummer Energy in Cambridge, and we used an old car battery which still had about 25 amp-hours capacity. We used a 12 volt digital timer (see here) to limit the playing to 8 hours a day and it has been running successfully (in winter!) for 40 days without the battery going flat [it finally went flat after 50 days on 23rd December after a week of cloud].

It is worth taking some trouble to mount the solar panel at the optimum direction towards the sun. We reckon that, for the period 21 May to 21 July (the main Swift attracting season, one month each side of mid-summer's day), facing south, with the plane of the panel at 35° to the horizontal is about right (the latitude of Cambridge is about 52°N). See here for a useful sun-angle calculator.

For an alternative 12 volt timer, we have tried DC 12V Digital LCD Power Programmable Timer Time Switch Relay 16A. it requires some wiring up, but is a low price and seems to work well. It is also available on Amazon.

The Cheng Sheng player amplifier

[We have now consolidated everything on attraction calls on this page]

Technology advances apace. We have discovered an even better idea for playing attraction calls, the Cheng Sheng 12V Stereo Power Audio Amplifier, with the player and amplifier combined in one box. So it is neater and slightly cheaper than the last idea, but the performance is the same.

Contributed by Dick

As with the original Box of Swifts, all of the electronics is in a single box. All it needs is a 12 volt power supply, and a speaker cable to connect a 1.5 inch car tweeter. The only soldering needed is to attach the tweeter to the speaker cable. Calls, in MP3 format, can be held on an SD card or a USB memory stick. 

Playing times can be controlled with a digital timer switch which can survive power cuts without needing resetting. 

The Cheng Sheng player amp can run off a 12 volt car battery, it consumes between ~0.3 amps and ~0.5 amps, depending on the sound volume (0.5 amps hurts your ears). Useful options are a 12 volt timer and solar panel for battery recharging.

These configurations are easy to put together yourself. You can order the player/amp singly, the speakers in pairs (which could be useful), but cheap power adapters only seem to come 5 at a time.

Although the Cheng Sheng player amp works out of the box, just switch the power on and it starts playing, it does not come with any instructions to explain what the buttons mean, so we have written some here (File>Download for pdf) [these were updated on 2/7/2013].

Websites for the components are: [Note prices and availability may have changed since posting this, so it is worth Googling for alternatives]

Cheng Sheng player amp

Another site for Cheng Sheng player amp

Maplins 1.5" car tweeters quantity 2

UK 12V power adapter

Another site for UK 12V power adapter

1 GB SD cards

Rodney Monteith has brought our attention to the Kinter MA-800 as an alternative to the Cheng Sheng.

Timer Switches

We have tried quite a few 240 volt timer switches. We prefer a digital timer because it can survive loss of power without losing the current time or program settings. However, the majority of them are quite difficult to use because of their arcane user interfaces. Cheaper ones frequently break down and lose their settings, or don't work at all after having them for a short period. Our current favoured timer is the Time Guard TG77 7 day timer. It is simple to program, is reliable, it has an on/off light and is available at a good price from John Lewis in the UK, see here.

Websites for Swift calls in MP3 format are:

Netherlands Swift Protection downloadable calls recorded by Rosanne van Oudheusden. This site has been reorganised, the recommended track numbers now are 1, 10, 13 and 14 (or 14a or 15a)

Set of selected Swift calls.zip  uploaded by Rick Wortelboer to the files section of SMSWW; requires login to SMSWW. These are some of the same tracks as the previous link, with quiet periods inserted.

Swift Conservation well tried calls on CD and supplied in MP3 format.

Jacobi Jayne good quality calls on CD - need converting to MP3.  Expensive.

It is also worth Googling for Swift calls, we found these:

Latvian swift calls we have not tried these, but they sound OK

More Dutch calls these sound OK too.

12 volt battery driven systems

If mains power is not available, then a 12 volt battery can be used as described on this post

Tools for manipulating sound files

For online format conversion try  http://media.io/ to convert audio files.

http://audacity.sourceforge.net/ is also a good program for performing manipulations on sound files

The AfS Attraction Kit

UPDATE 15th Nov 2012: This post has been superseded by a newer idea. However, the amplifier and speaker parts of this system are still appropriate for those who wish to use something like an MP3 player.

Last year, we produced the 'Box of Swifts' for attraction call playing and we deployed about 35 of them. The component costs were quite high, and it took a couple of hours of volunteer skilled soldering to assemble them, and, at the price we sold them, we ended up losing money, because of ullage and our decisions to donate them in situations with no budget.

Requirements of an attraction system
The requirements that the BoS satisfied were:
1. Simple installation: this was achieved by having a small 1.5 inch car tweeter on the end of a single piece of speaker cable. It is easy to attach to a nest-box 6 metres high, and there is no need to get mains power to it.
2. Simple operation: the BoS starts playing when the power is on and stops when it is off. There is no messing around with clamps on play buttons, nor having to restart the thing manually after a power failure.
3. To this we would add one other thing, that volume control is on the ground; for the BoS, this was not an issue because it was always set to maximum because of the limited power of its amplifier.

The biggest problem for us with the BoS was the component cost and the time taken to assemble them.

New Plan for 2013
So we have a new plan. We found an off the shelf SD card player, for about £12 that does everything the BoS does, except it doesn't have an amplifier. It is intended for use in an automated telephone answering system. So we then went searching for an amplifier, and found a good one for £9. Add in some bits of cable, a power supply and a speaker, the complete component cost comes to less than £40 per kit, with only one soldered connection to connect the speaker to the speaker cable.

The resulting kit does everything that the BoS does, but can deliver considerably more volume. The only disadvantage is that it doesn't come in a neat little black box.

AfSAK assembly diagram

Sourcing the components
Most of the components come from China, and apart from the SD card player, you can't buy things in singles. Amplifiers come in batches of 5, splitters in batches of 20, power supplies in batches of 5,  speakers in 2's (but you may want to drive 2 speakers) and speaker cable in lengths of 100 metres. The only thing you need in addition is a 240 volt digital timer with battery back up (rough cost £8).

Battery-driven systems
Depending upon whether you have 1 or 2 speakers (the amplifier has sockets for 2 speakers) and the volume setting, the AfSAK consumes between .3 and .5 amps at 12 volts. So on a fully charged 60 amp hour car battery it could run continuously for between 120 and 200 hours. So, if one rationed the playing to, say, 4 hours per day, using a 12 volt timer (rough cost £18), it could keep going for between 30 and 50 days. Add a solar panel and it could keep going indefinitely.

We are happy to let anyone have the sources of all the components, or we may consider supplying the complete assembled kit for £55 plus postage for a single speaker system, £65 for 2 speakers.

If you have any comments or suggestions or want to know more contact us at actionforswifts@gmail.com

Box of Swifts - update

Back in June 2011 we described our Box of Swifts for playing calls to attract Swifts into nest-boxes. As a result, we have been somewhat overwhelmed with demand, to the extent we cannot accept any more requests. 


The BoS greatly reduces two sources of hassle:
1. Installing bulky speakers near to a nest-box 5 metres from the ground and supplying mains power to the speaker power supply. The BoS uses a small Car Tweeter with a single piece of low voltage speaker cable to it.
2. An automated system driven by a conventional timer to play calls at chosen times, using a player not designed for this sort of thing. The BoS starts or stops playing when the power is switched on or off, and it comes complete with Swift calls.


So, in order to try to mitigate any disappointment, we suggest here an alternative which is fairly easy to put together yourself. This alternative solves 1, and to some extent 2.

A Box of Swifts

Contributed by Dick Newell and John Clamp

Speaker, power supply and Box of Swifts

We are currently testing a small number of prototype Swift call players, built out of standard, low cost electronic components, including amplifier chips. The result, called "A Box of Swifts" is a simple to use, no hassle device with a power supply in (anything between 6 and 12 volts) and a single wire out to drive a small, quality speaker.
When power is switched on, A Box of Swifts starts playing for an indefinite period of time, until the power is switched off, so controlling it with a low cost timer is easy.

Cambridge Swift Tower "Bird Scarer"

Contributed by Guy Belcher

As there is no mains power anywhere near the Swift Tower, we have decided to use a Bird Scarer, programmed with Swift attraction calls, powered by a 12 volt battery, recharged by a solar panel.

The system was configured by Martley Electronics of Worcester and comprises:

BS3 Bird scarer (programmed with Swift attraction calls)
Run off a 75ah 12V leisure battery with a 5 watt trickle feed solar panel.
There is a dawn/dusk light sensor and a 12V timer for maximum flexibility.
Unless the timer is set it plays 5 minutes durations of calls at random during daylight hours.
There is a volume control. 
The complete unit is weather proof.

Approx cost inc. delivery is   £450.00

Why play the Swift CD?

Posted by: Dick Newell

Swifts in a frenzy, attracted to calls
played through a single speaker

While you can agonise over box sizes, entrance shapes, surface textures, directions, heights and concaves, all of these only have a marginal effect on success or failure in attracting Swifts into a nest box. The nearest thing to a 'silver bullet' is playing a CD of Swifts screaming, typically a duet of two Swifts calling 'sree-ree' to each other. When asked the question of how and when to play the calls, the simple answer is as loud and as long as possible, subject to not annoying anyone. There is an opinion that early morning and evening is best, but any time of day can be effective. It is also best to position the speakers as near to the boxes as possible, some even say in the boxes, but somewhere below the boxes in a window, or on the ground also works.

We know of cases of people getting Swifts into a box within 30 seconds of starting to play the CD; we also know of cases of people playing the CD for 5 years without success, but this is unusual and we suspect that the CD has not been played sufficiently consistently throughoutt the season. In our projects in 2010, in 5 cases where we know that the CD playing was well organised and consistently carried out throughout the season, 4 of these succeeded in acquiring new occupants.

Switching CD players on and off is a tedious chore, but this can be made easier by using a remote infrared switch so that, while sitting in the garden with a glass of wine, you can switch the CD on, when the Swifts come by, without getting out of your chair. However, it is well worthwhile investing some effort in setting up an automated system, driven by a timer. The simplest way to do this is to plug your CD player power supply directly into the mains, then plug the speaker power supply into a timer. Set the CD player to repeat, so it plays 24 hours a day, but the sound emerges from the speakers only when the timer says so. Now, if your CD player is playing for 6 weeks continuously, it tends to thrash the player, so maybe an MP3 player would be preferable.

Alternatively, plug the CD player into the same timer, by using an extension with two sockets, and, hold the play button down with a clamp, rubber band, clothes peg or whatever comes to mind. On some CD players (e.g. Sony Discman), they will start and stop playing as the power is switched on and off. Now, you do this at your own risk, as you would be using the equipment in an unauthorised way, but we are talking about a 4.5 volt system here, which would be hard pressed to cause a fire.
Some ghetto blasters also behave in this way if the play button is held down.

An extreme CD exponent is Brian Cahalane in Crumlin, Northern Ireland. Brian plays his CD from dawn until dusk, from the end of April to early August, through multiple speakers and as loud as possible. The result: he quickly acquired a colony of 22 pairs of breeding Swifts, and many more clambering to get into his boxes.

Now, one doesn't need to go to these extremes, but playing the CD from about the 3rd week of May, when prospecting non-breeders arrive, until the second week of July, every day for at least 2 hours a day will give a better than 50% chance of success (We don't have enough hard statistics to defend this claim).

If your nest-boxes are replacements for nesting places that have been destroyed, then start playing at the beginning of May to show the displaced birds where there are new nesting places.

You can buy a CD from Swift Conservation or Jacobi Jayne

You can also download Swift calls from the Dutch Swift Association
It is suggested that you use the .wav versions for CD players and the MP3 versions for MP3 players:
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POSTSCRIPT 30 Nov 2012: See our latest idea for attraction call playing: the Cheng Sheng player amplifier.