Count me in!

I’ve been told that there are only three types of people in this world: those that can count, and those that can’t. For those that can’t, the numbers game can be something of mystery, or even a painful experience. But for those that can (and those that can’t!), numbers form the basis of most of the measurements by which we judge our lives. They represent targets, achievements and goals, they provide a benchmark against which we strive to improve or compete, and mark the passing of time to give context to those achievements.

So it is in conservation and birding. We count birds; whether to determine population trends over time or simply for competition with others or ourselves. We count numbers of individuals, breeding pairs, numbers of species, fledged young, and we do this repeatedly to assess the health or otherwise of a particular habitat or location, and then to see what happens in that place over time.

One particular place where this has been happening lately is the Isles of Scilly. The archipelago is a group of over 100 islands (depending on the tide) located 28 miles off the tip of Cornwall, with a permanent population of around 2,200 people. For the last nine years I have been privileged enough to visit the islands each autumn to lead guided walks for the RSPB on Tresco, one of the five inhabited islands. The purpose of the visit is to raise awareness of the work the RSPB are doing on the islands for wildlife, and success is largely judged on numbers: how many people we meet, how many walks we do, how much money we raise, how many members we make. But these numbers don’t tell the whole story here. Other numbers have started to become more important.

Storm clouds off Bryher

Back in 2013, a partnership project involving five different organisations began, with the aim of improving the productivity of breeding seabirds around the islands. About 20,000 individuals from 14 different species of seabird come to the Isles of Scilly to breed each year, but populations of most of them have been doing badly due to predation of eggs and chicks by rats. The Isles of Scilly Seabird Recovery Project aims to remove rats from St Agnes and Gugh, two of the most important seabird nesting areas, and started doing so in autumn 2013. The 84 inhabitants of the islands all signed letters of support for the proposal, and baiting began. Over just six weeks all signs of rats disappeared, and no rats have been seen since!

A survey tunnel

The knock on impact of this work was seen in 2014, when surveys revealed manx shearwater chicks on St Agnes and Gugh surviving to fledging – 10 of them in fact. And in 2015 there were 28 of them. This may seem like small fry, but this is where numbers come in. Not a single manx shearwater chick had been recorded by anyone on those islands in living memory. None. That’s zero productivity over perhaps 100 years. And now there are at least 28 chicks leaving the islands for a life at sea. Even better, storm petrel chicks have been confirmed in 2015 – the first for many years.

A Manx Shearwater chick

Conservation projects are rarely so successful so quickly, and we can only assess how well they are performing using data – without a baseline we would have nothing to compare to, and without rigorous, consistent survey techniques we would not be able to draw reliable conclusions. The Isles of Scilly Seabird Recovery Project is a fantastic example of what can be achieved through partnership working and community support, and of course an excellent example of how numbers have shown that success. Let’s just hope the surveyors were not among the five out of every four people who have problems with fractions.