BBOWT has a dedicated band of volunteers who go out in all weathers to find out the latest news on the wildlife front. From studying otter spraints to counting butterfly eggs, watching water voles to tagging orchids, they are out there collecting data on the creatures of our three counties.

It is data which helps the trust to build up a picture of what is happening to our local wildlife year on year, and how it is affected by all kinds of events from extreme weather to conservation work.

Colin Williams, reserves ecology officer for BBOWT, said: “Without surveying the wildlife on our reserves, we would have no idea whether the habitat management work that we do is effective or not.

“Surveys provide us with the evidence to show that conservation efforts are being rewarded. But it also shows us which species are under threat and need a little extra help.

“For example, if survey work shows that a chalk grassland site is being taken over by scrub, and there’s a decline in butterflies relying on this type of habitat, we would suggest that reserves staff and volunteers should clear the scrub and increase grazing to make the habitat healthy again.”

The survey data that BBOWT collects is not only interesting to the trust, but it also serves to let everyone know how our local wildlife is doing.

BBOWT’s butterfly survey data helps Butterfly Conservation compile its annual, UK-wide report about the state of our butterflies.

Last year was the second worst on record for butterflies, following the devastating floods of 2007 — also one of the ten worst years. Several species had their lowest ever recorded numbers in 2007, including the small skipper, speckled wood, and chalkhill blue — all Oxfordshire regulars.

Colin said: “On our reserves we’ve noticed a decline in the small tortoiseshell, for example. Once common, this butterfly has been hit hard by a parasitic fly first noted in Britain in 1999. The fly, common on the European mainland, is thought to have become established as a result of warmer temperatures. We’ll be keeping track of the small tortoiseshell this year to see how it has fared.”

During recent times, nightingales have dramatically declined in Oxfordshire. These well-known virtuosos of the bird world were once regular summer visitors to the UK but now seem to be restricted to the south and east of England, due to the loss of woodland habitat.

But the good news is that records from this spring show an increase in numbers on some BBOWT nature reserves. Colin hopes that these individuals are not just passing through but will stay to nest. And you still have a good chance of catching one of these songbird’s remarkable performances until early June. Every April, volunteers and staff studiously head out to BBOWT’s Iffley Meadows Nature Reserve in Oxford to survey a spectacular display — the thousands of nodding, chequered flowers of snake’s-head fritillaries.

Since BBOWT took over the management of the site in 1983, the population of snake’s-heads has grown from a mere 500 plants to more than 65,000 at their peak in 2002.

But the summer floods of 2007 had a devastating effect.

Water lay on the meadows during the summer, rotting the bulbs. The 2008 count showed that the population had halved from the previous year as many plants had simply died in the extreme weather.

Colin is hopeful that the worst is over: “The final total count for this year is nearly 38,000 which represents a significant increase on the 26,000 counted in 2008. This is good news and hopefully shows a steady recovery of this rare and beautiful flower.”

Julia Armstrong, BBOWT’s Water Vole Officer, is pleased that water voles are doing well on the River Windrush: “It’s one of our success stories. Water voles were introduced by Oxford University’s Wildlife Conservation Research Unit (WildCRU) along the lower Windrush and last year’s survey showed that, two years on, they’re not only doing well but have significantly expanded their range.

“The bad news is that a former stronghold for these lovable creatures, the Oxford Canal, has shown a steady decline over the last few years. We only found a few signs of water vole activity in 2008. The main problem is predation by mink. It’s a real shame, as local people used to report seeing voles along the canal all the time.”

Plans for 2009 surveys include the more northern end of the Oxford Canal and the River Ock in Abingdon. Julia added: “We’ve had sightings reported from both areas so we’re hoping to find some new colonies. We know there’s a strong population around Abingdon so it will be good to get some positive survey results.”