Mass frogspawn survey sounds a warning for Britain’s wildlife
Mass observations of frogs spawning have sounded a warning bell not only for the future of the common frog but also for Britain’s wildlife more generally.
Frogs are so locally adapted that they may not be able to cope with even modest climate change, research has found.
And what’s true of frogs is likely to be true for many other poorly-dispersing species. Their only alternative will be to move and that’s not an option unless there is swift action to create landscapes that work for wildlife as well as people.
That’s the conclusion of a paper published in the Proceedings of the National Academy of Sciences of the United States of America. It analysed more than 50,000 UK observations of first frogspawn from 1998-2006 collated by Nature’s Calendar, a national survey coordinated by the Woodland Trust.
A unique approach to assessing local adaptation was developed. It compared how relationships between temperature and spawning dates vary across Britain with how they vary over time.
All populations spawn earlier in warmer years but southern populations do so several days earlier than northern ones even if they experience the same temperatures, a difference that can be attributed to natural selection. Indeed, it was discovered that this local adaptation is detectable between populations throughout Britain in neighbouring 150km grid squares; areas the size of an average English county.
The paper’s authors come from Imperial College London, the University of Edinburgh, the Max Planck Institute for Demographic Research in Germany, and the Woodland Trust.
Joint lead author Albert Phillimore, from the Division of Biology at Imperial College London, said "For frog populations to keep in step with medial projections of climate change for 2050-2070, they may need to spawn about 30 days earlier. Their current flexibility, however, may only enable them to spawn 7 days earlier. It’s unlikely that frogs will be able to evolve sufficiently rapidly, so they will need to move northwards. All frog populations face a challenge but the most southerly populations are in the greatest predicament because the English Channel provides a total barrier to immigration from further south."
"Local adaptation has been assessed in relatively few species, as it has previously required logistically-challenging experiments”, said co-author, Richard Smithers, the Woodland Trust’s senior conservation adviser. “But like frogs, a great many other species are poor at dispersing and may be locally adapted, particularly those associated with ancient woodland. If that’s the case, it makes it all the more urgent to increase native tree cover, as we’re one of the least-wooded countries in Europe."
Jarrod Hadfield, joint lead author from the University of Edinburgh, added, "Our study demonstrates the great value of citizen science. The observations collected by the public have enabled us to gain important, if sobering insights, into the evolutionary challenges that frogs are likely to face."
Notes to editors
For media enquiries contact:
The Woodland Trust Press Office on 01476 581121, email: media@woodlandtrust.org.uk
The Woodland Trust:
The Woodland Trust is the UK’s leading woodland conservation charity. It has 300,000 members and supporters.
The Trust has three key aims: i) to enable the creation of more native woods and places rich in trees ii) to protect native woods, trees and their wildlife for the future iii) to inspire everyone to enjoy and value woods and trees
Established in 1972, the Woodland Trust now has over 1,000 sites in its care covering approximately 20,000 hectares (50,000 acres). Access to its sites is free.
The authors of the paper are:
Albert Phillimore, a Junior Research Fellow at Imperial College London focusing on evolutionary responses of populations to climate change.
Jarrod Hadfield, a fellow at Edinburgh University who uses statistical approaches to understanding how evolution underpins variation in traits and behaviour within species.
Owen Jones, a research scientist at the Max Planck Institute of Demographic Research in Germany. His research combines ecological and evolutionary theory with statistics.
Richard Smithers, senior conservation adviser with the Woodland Trust who has been involved with Nature’s Calendar since 2000.