Last updated: 06 March 2012
Adam explores the science of phenology - the study of nature's calendar.
Broadcast Tuesday 6th March at 7pm
This week's programme begins on a patch of waste ground next to a busy main road in Cardiff. For Dr. Tim Rich, a botanist at the National Museum Wales, this was one of the stopping-off points on a walk he took on New Year's Day 2012 to see how many wild flowers he could find. He was amazed to discover 63 different species in bloom at a time of year when you'd expect to find no more than 20.
Is this midwinter flowering a one-off or is it part of a long-term trend? Adam explores the scientific evidence behind the widely-held belief that spring is getting earlier. The study of the timing of natural phenomena is known as phenology and Adam is joined on the programme by phenologist Dr. Tim Sparks of Coventry University who gives a brief history of the subject and explains that data can come from many different sources - from wild plants and bird migrations to frogs spawning and insects hatching.
Adam visits Goronwy Wynne at his home in Lixwm in Flintshire. Goronwy is a botanist and formerly the official botanical recorder for Flintshire. From his extensive collection of botanical books, Goronwy selects one of his oldest field guides and one of the newest and shows Adam that the dates for many spring-flowering species have come forward by at least a month in the last century or so. Adam and Goronwy also take a walk to some nearby common land to discover the first lesser celandine of spring.
Another sign of spring is the arrival in our skies of summer migrants and the sound of garden birds singing their hearts out as a prelude to courtship and breeding. Science Cafe producer Jeremy Grange visits the RSPB's reserve in Conwy to meet the warden Julian Hughes and to discuss the implications for birds of spring getting earlier - for example the fact that their insect food sources might have vanished by the time the chicks hatch.
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