The survey was undertaken during the evening of 4th May 2007 at Tophill Low by Yorkshire Naturalists Union members Richard Sunter and Professor Brendan Ballenger, and HVWG Members Peter Drury and Les Bardwell.
After dark, a beam of light was directed into the water from the banks of ponds where access and terrain permitted. Details of quantities and sex of targeted species were then recorded.
Results
Six bodies of water from around the reserve were surveyed and a count of approximately 130 Great Crested Newts was recorded. In addition a Smooth Newt and low numbers of Marsh Frog, Common Frog and Common toad were also noted. The low numbers of frogs and toads may be due to the timing of the survey which was well after their breeding season and they may well have dispersed from the breeding area.
Regarding the low numbers of Smooth Newt, the reason is open to various possibilities. The high numbers of Great Crested Newts, the possible impact of Marsh Frogs, the weather conditions or the possibility of individuals being overlooked due to the attention given to recording the Great Crested Newts.
it is usual to conclude that only 10% to 30% of an actual population will be seen using the survey method employed.
Conclusions
Tophill Low supports a regionally important colony of Great Crested Newts and also supports a range of amphibians typical of the Holderness area.
The absence of Great Crested Newts in some ponds around the reserve is likely to be due to the presence of fish in these bodies of water. It is advised therefore that no transfer of biological material is made between ponds to avoid the accidental introduction of fish into fish free areas.
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