Although there are signs of spring in our flowerbeds, ponds and hedgerows, the arrival of the first returning summer migrants still seems a long way off.
Some summer visitors are already on their way, however, and this is something that can be seen in the ‘live’ data feeds from the British Trust for Ornithology’s (BTO’s) satellite-tagged cuckoos (www.bto.org/cuckoos), for example.
In just a few weeks the first returning house martins will appear and it will not be long until these long distance travellers will once again be nesting on suitable houses, factories and other buildings. We know very little about house martins, even though they nest alongside us. The lack of knowledge around where in Africa they winter is perhaps unsurprising: Africa is vast and the house martins spend much of the time on the wing above the forest canopy. That we know so little about their breeding ecology here in the UK is a surprise, however, particularly given concerns over their declining numbers – surely this is a species that we should be looking at?
This spring, the returning house martins will be greeted by an army of volunteers, made up of birdwatchers and homeowners participating in the BTO House Martin Study. This two-year project is now entering its second year. While last year’s effort was on identifying where house martins occur, and in what numbers, the focus now shifts to their breeding ecology. Volunteers are being asked to follow the progress of individual nests through the course of the breeding season by collecting simple information on the nest and on the activity that is centred on it. BTO researchers want to understand how much effort goes into building the nests, identify how many breeding attempts a pair makes each year (there is a suggestion that it might be two but it could be three) and establish which building features support successful breeding – e.g. do the birds have a preference for particular types of building?
There is good evidence that Suffolk’s house martin populations are in decline, so the BTO is keen to secure good coverage across the county. If you have house martins breeding on your house, or have a colony locally that you would be able to monitor, then the BTO is keen to hear from you. Even though it will be a few weeks before the birds arrive at the breeding colonies, potential volunteers are being asked to register their interest now by visiting www.bto.org/housemartins, where they can read the survey instructions and discover more about what is involved.
The information collected through the survey, coupled with that collected last year, will improve our understanding and help those involved in house martin conservation.