Amphibian and reptile declines – UK perspective
The UK supports a range of iconic mammal species including hedgehogs, water voles, badgers and several bat species. However, in recent years, research by various conservation bodies has found startling declines in many of these species. Research led by the Wildlife Trusts indicates there has been a 30% decline in water vole populations since 2006, which represents an approximately 3% loss in populations per year1. Of more concern, is the dramatic decline in the hedgehog which is estimated to have declined by 66% over the past 13 years (5% decline per year)2. Increased agricultural intensification, use of pesticides, habitat loss and fragmentation have all attributed to the decline which has been reported by the British Trust for Ornithology2. In addition, several of the UK’s iconic bat species are in decline, as reported by Bat Conservation, including the brown long-eared bat which has declined by 31.3% since 1999 (2.2% decline per year)3.
Amphibians and reptiles are generally less understood by the public who often perceive these species differently to iconic mammals. However, many populations of our once common amphibian species are in decline. Common frog, common toad and natterjack toad populations have been reported as being in decline since the 1970s4,5. Recent research in 2016 by Froglife and the University of Zurich has shown that common toad populations have declined across the UK by 68% over the past 30 years, which approximates to a 2.26 % decline per year. This value is comparable to the declines in many of our iconic mammal species and highlights that significant declines may be widespread across our native fauna. The reasons for the decline in the common toad are similar to those affecting hedgehogs including habitat loss and fragmentation, pollution and climate change. The adder, being the only native venomous snake in the UK, often has a poor perception from the public. However research by Natural England and Froglife in 2002 has indicated significant population declines in the adder, especially from the Midlands6. In this study one third of adder populations were estimated to consist of less than 10 individuals which puts them at high risk of extinction. These declines are likely to be attributable to poor habitat management including agricultural intensification as well as public pressure (recreation) and persecution6. At Froglife we aim to raise awareness of the declines in our native amphibian and reptile species, especially those which were once common. We wish to highlight that widespread amphibian and reptile species, such as the common toad, are suffering declines equivalent to iconic mammals such as the water vole and hedgehog. At Froglife we carry out extensive practical habitat creation and restoration each year, both locally and nationally, with the aim of improving environmental conditions for our native amphibians and reptiles and aiding to conserve populations of our valuable herpetofauna.
References
1Wildlife Trusts (2018). http://www.wildlifetrusts.org/news/2018/02/26/new-report-points-30-decline-water-vole-distribution. Accessed on 13th March 2018.
2BTO (2018) https://www.bto.org/science/monitoring/hedgehogs. Accessed on 13th March 2018.
3Bat Conservation (2018) http://www.bats.org.uk/pages/species_population_trends.html. Accessed on 13th March 2018.
4Beebee, T.J.C. (1973) Observations concerning the decline of the British Amphibia. Biological Conservation, 5 (1): 20-24.
5Beebee, T.J.C. (1977) Environmental change as a cause of natterjack toad (Bufo calamita) declines in Britain. Biological Conservation, 11: 87-102.
6Baker, J.R., Suckling, J. & Carey, R. (2004) Status of the adder Vipera berus and slow-worm Anguis fragilis in England. English Nature Research Report 546, English Nature, Peterborough, UK.