csp | Crieff Swift Project

About the Crieff Swift Project

Because of social media, you could be forgiven for thinking that concern for the welfare of swifts in the UK and Eire is a recent fad, of interest to only a few but over the last two decades the swift population in the UK has plummeted. This marked decline has provoked a reaction which has become increasingly noisy, thanks in large part to FaceBook and Twitter and the facility for volunteer conservation projects to share information much more effectively than they could.

A serious depletion in numbers of a species can often be attributed to humans and their affect on the species’ habitat. In the case of the swift, their lives are bound up with ours far more than many people realise. In parts of the world, like Indonesia, you will see swifts nesting on ledges in caves which are difficult for predators to reach and some swifts are known to nest in trees in other parts of the world but, generally speaking, our common swifts rely on us to provide them with their breeding habitat, in and on our buildings.

Many people unwittingly give swifts a home when they neglect their buildings, some of which are well suited to providing nesting opportunities. Older buildings in particular have nooks and ledges away from the reach of predators and, so long as these are out of sight and out of mind, swifts will happily cohabit with us. However, much of our ageing building stock is 100 to 150 years old and those buildings which have not received proper maintenance in living memory are either falling into ruin or are now being refurbished to modern standards. When modernising Victorian houses, the accepted thinking is that nooks and crannies are not a good idea and one can understand why.

To mitigate the decline in swift numbers, people are encouraged to erect swift nest boxes where sites are suitable but nest boxes will not be as permanent as a nest which is part of a building; swifts are loyal to the same nest all their lives. A series of wall head nests could be home to a colony which may have nested in the same place for many generations. These nests are arguably irreplaceable but good quality swift boxes can be part of a strategy to hold the line while we look for better ways of addressing the problem.

Is it a problem? Is it not just nature at work, forcing adaptation? There is much contradictory information about the common swift's status. Some statistics obtained from parts of southern Europe indicate the population is stable and the status is of "least concern" whereas in northern Europe its status is recorded as "of concern"; the RSPB has the swift on its Amber list. The British Trust for Ornithology published monitoring results are about ten years old but in these you can see a mixed pattern. Mostly it shows a decline in populations, in particular in densely populated areas such as London, Birmingham, Leeds, Belfast and Aberdeen. Some areas show growth in population but, by the aggregation of recorded swift densities, the overall is a decline of around 60% in the period 1994/96 and 2007/09. In Tayside the picture is one of decline of around 50%. We are waiting to see the publication of the BTO's Bird Atlas research to have a more up to date picture. The IUCN's Red List records apus apus as being of "least concern" but we do not feel this is meaningfully representative for the UK. It is in northern European countries, at the edges of the swift's range, that the decline is being seen and in the UK, at the current rate, we could lose them if we do not do something about it - now.

There is a large network of interested bodies, some in educational institutions, some government funded and some purely voluntary and these people speak to each other and share information and this network is growing and the conversation is starting to be heard. It is not enough though; the place where a meaningful difference can be made is, literally, on the street. We need to know where the swifts are, where they are breeding and how much in peril their breeding sites are. For example, if a dilapidated hotel is sold and refurbished or if it is demolished, the process will probably happen in complete ignorance of any nest sites which have existed in the top of that hotel, possibly for many decades. One decision can wipe out a breeding site for a very large established colony…

The swift breeding season is short. It is during the breeding season that we will be able to see swifts, close up. They arrive at their nest sites in Scotland around the end of the first week of May and three months later they are gone. They are loyal to their nest for life, which could be anything from eight to twenty years with a suggested norm of around eleven years. Young swifts are ready to look for a nest and breed after two or three years and, as they tend to social groups, it is thought that they will be looking to pair and nest in association with the group where they were born or another group nearby.

It is unfortunate that we do not have access to records of swift activity in our towns which could tell us how long colonies have existed. Some may be very old. For example, the Glenhead swifts were breeding in a wall head site which was probably unaltered since the building was extended and harled in the 1920s, so the colony there could have been very old. Because no-one fiddled with the building since it was remodelled, conditions in which swifts could thrive were maintained for at least eighty years and possibly longer. There is a theory that the air currents nearby and the effect these have on the swifts’ access to food is a factor and these air currents we can assume are a fixture in the grand scheme of things but the homing instinct gives a strong, lasting bond to the nest site.





© A.P.Rodger 2018