Last month we got official confirmation about the new national status of swifts and house martins (above) in Britain. Although anyone over 40 years old with even the slighest interest in nature will have watched these glorious summer birds become less and less common. Places where they used to breed have increasingly fallen silent. Now we have the facts in black and white, or perhaps in scarlet letters. Because both have been declared red-list species in Britain and at risk of extinction, with swifts having fallen by 58% and the martin by 57% since 1995.
The grim background to this story is that 70 species, about double the number previously red-listed in 1996, have now been placed in this highest category of threat. Just as worrying is that a further 103 birds are on the amber list. Why does that matter? Well until recently swift and house martin were amber-listed birds also. The red and amber lists suggest that there are troubling population trends for three-quarters of all British birds. Just a quarter of our avifauna has a positive environmental status with a green listing.
The central issue accounting for losses of swifts and house martins is probably revealed in the Krefeld report, a German document that shows how insects have declined in that country by 75 per cent in the last 40 years. Most signficant is that these changes came not in the wastelands of industrialised farming but from within the country’s protected wildlife network. Insect biomass is directly implicated in the losses of insectivorous birds. Why would we be surprised that 3.2 billion birds have vanished from North American skies and now 600 million from Europe over the same period? These are precisely the areas with the longest history of intensive agricultural use of insect poisons. (let’s call a spade a spade here: they are not ‘pesticides’, they kill so-called ‘pests’ and everything else.) Here’s a swift (below) with its throat bulging with 300-1000 insects that it will feed to its chicks.
Below is a heart-warming scene involving house martins en masse as they gather nest-making materials. It was taken in northern Greece, where house martins are still in extremely good numbers, but there is something else in the image that may help to explain why this little pied mouse has plunged so dramatically in Britain. Mud. House martins need it to make their nests and you invariably require livestock, primarily cattle, to create mud. That is exactly what you see in the Greek shot. Otherwise the birds use industrial and agricultural sites or natural places – river banks and temporary puddles – in order to collect their essential pellet-sized building materials. My guess is that a mud shortage is a lesser but significant factor in UK house martin declines.
There is a third factor in the losses of house martins and swifts and this is one we can all do something about. Both birds originally would have used a range of natural nest sites – caves and cliffs or treeholes – but at differing times in the history of civilisation, these two switched to nesting above our heads in roofs. (Below is an original house-martin nest-site on the chalk cliffs at Flamborough and you can read my fuller post and Guardian pieces here and here).
But things have changed dramatically in the last half century. A new requirement for higher levels of insulation and changes in construction materials have probably worked against both birds, but especially swifts, which need access holes in our roofs. Our increasingly tidy-minded habits have probably played a further part in evicting house martins. I have actually seen people knock nests down, which is illegal, or hanging decorative Xmas-type lights permanently on the gutters in an attempt to deter the birds from building, which is probably legal but appallingly uncaring. Loss of nest sites by both birds is surely a major factor in their declines.
The sad disappearance of these two magnificent creatures has mercifully not gone unnoticed. And there are many things that anyone can do. I am going to list a few of the positive ways in which people can and do help house martins and swifts.
There is, for example, a wonderful group called House Martin Conservation UK and Ireland. You can find more about their work on the website here and on Facebook here. Both links give you access to an entire community of friendly people and brilliant ideas about what to do. House martins need an eave so that they can usually glue the mud cup both to the back wall and also to a horizontal surface at 90 degrees to vertical. But you can buy ready-made cups that sit on boards and slot into exactly that space. My picture of Millers’ Dale station shows that success is not guaranteed. The bird still often prefer their own homemade versions. House martins have thousands of years of history of using our sites but building their own nests. Switching to the ready-made alternatives may take a little time, so try to be patient.
House Martins are also highly communal and like to be with friends. Here is a picture recently taken at Castro Verde in Portugal which shows how they love to be with one another. So, if you have success with luring a single pair into your purpose-built box then perhaps put out others nearby. One house martin pair is great, but 2 or more is better still.
The ready-built nests are now made by a range of manufacturers at relatively small cost. My personal favourite manufacturer in our area is Peak Boxes, which is constantly innovating on new ways to encourage birds and to create nesting places for martins and swifts, and for a whole suite of other hole-using species. Here is their latest idea for a socially minded creature like house martin, a tower block complete with more than a dozen nests at the equally brilliant rewilding Derbyshire farm Sunart Fields run by Geoff and Rachel Evatt. Link here.
Swifts are similarly adapting to human-made alternative nest-sites. We have one of Peak Boxes’ seven-unit apex nest-sites for swifts, so far, it must be said, with imperfect success for the target bird. The best means of luring swifts to new boxes is to play tape-recordings of their social calls. Most of the manufacturers, such as Peak Boxes, sell these sound systems. And they have led to startling successes, sometimes with swifts moving into freshly erected boxes within hours. The unit structures at Peak Boxes have been designed after decades of research by swift aficionados like Mark and Jane Glanville.
The key point to make is that you don’t need a multi-nest box to have an impact. A single occupied site makes a difference and the other possibility is to work with neighbours to develop a community project. A real long-term solution would be if all new-built properties came with special nest bricks for sparrows, starlings, martins and swifts so that this traditional roof-nesting bird suite were accommodated at source. The groups often campaign for these outcomes.
There is a comparable suite of active swift groups which can help with advice and contacts. There is the pioneering specialist collective Swift Conservation which has a website here. There is another Facebook equivalent with many members called Save our Swifts, Swallows, Sand Martins and House Martins. If you use social media their dedicated page is here. All of the mainstream conservation organisations have page or groups dedicated to the birds and there are a number of other county-based collectives. We have a fabulous example locally run by volunteer Nick Brown for the Derbyshire Wildlife Trust here. And in Buxton itself we have a wildlife group that is partly dedicated to counting and censusing the local swift population. Email if you would like to know more.
One of the enormous pleasures of helping these two magnificent birds it the thought that action taken on your own doorstep could have direct consequences over the forests of the Congo or in the skies above South Africa. For they are truly world-wrapping migrants. They make our planet a single place and the whole world one community.