Dragons of Ramsey Heights A review of the ponds and great crested newt Triturus cristatus population at Ramsey Heights Countryside Centre

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1 Dragons of Ramsey Heights A review of the ponds and great crested newt Triturus cristatus population at Ramsey Heights Countryside Centre Josh Hellon and Terry Moore January 2015 Did you know? Great crested newts have full protection under UK law, making it an offence to kill, injure, capture, disturb or sell them, or to damage or destroy their habitats (Froglife 2015). Pond management should be planned carefully to avoid any harm to newts and surveys must be carried out by licenced ecologists. (Photo Terry Moore 2015) Summary The reserve at Ramsey Heights Countryside Centre supports a population of protected great crested newts Triturus cristatus. This report presents a summary of habitat changes and monitoring at the site from 1998 to present. It is considered that natural habitat succession and the presence of fish in one of the ponds has had a negative impact on the great crested newt population at the site. Recommendations for future management and monitoring are made in the report.

2 Introduction The Ramsey Heights Countryside Centre is a small, 9 acre reserve based on the site of Victorian brickworks. It is within the Great Fen project area, directly west of Woodwalton Fen National Nature Reserve (NNR). The site is a mixture of grassland, scrub, wooded areas, buildings, drains and a network of ponds. These ponds and the surrounding areas provide habitat for a wide diversity of wildlife, including the protected great crested newt (GCN) Triturus cristatus. Description of the ponds Figure 1 Map of reserve showing location of ponds. Areas marked in blue are permanent ponds (Ordnance Survey Crown copyright 2015) Maps of the site (fig. 1) show thirteen individual ponds on the reserve, but it is known that three of the smaller ponds no longer exist: 3, 9 & 12. There are currently ten ponds at the site that hold water for all or most of the year; 1, 2, 4, 5, 6, 7, 8, 10, 11, & 13.

3 Pond 1 Figure 2 Photograph of pond 1 taken from the south end showing bisecting bridge Pond 1 is a large pond made up of two main sections bisected by a bridge (fig. 2). The pond is surrounded by overhanging trees and is fringed by common reed Phragmites australis. The following management activities have been carried out since 2001: October 2001 reed and overhanging vegetation removed from northern section; July bridge installed and vegetation cut back; January 2007 northern part of pond cleared by Cambridgeshire and Peterborough's local Amphibian and Reptile Group (CPARG) team; July 2008 trees cut back from edge, allowing more light in; February 2010 old bridge replaced; January 2011 manual pond clearance with volunteers; January 2012 contractors removed reed; 2013 Fish removal considered as large numbers of common rudd Scardinius erythropthalmus spotted in the pond.

4 Pond 2 Figure 3 Nylon mesh to prevent fish movement between ponds 1 and 2 This small, deep pond is adjoined to pond 1 by a pipe that was covered by mesh in May 2014 to prevent fish movement from the main pond (fig. 3). Pond 3 This kidney-shaped pond is now dry at all times of year. Pond 4 This small pond is heavily overgrown and shaded by trees but has water at all times of year. Pond 5 This pond is larger and deeper than pond 4, but also heavily overgrown and shaded. It has water at all times of the year. Pond 6 This pond is often dry during late summer, but has water at all other times of year. It is heavily overgrown and shaded. Pond 7 This narrow inlet is now an isolated pond that has water at all times of the year. It is likely that it was connected to pond 8 in the past.

5 Pond 8 This waterbody was the harbour for loading bricks and unloading coal when the site was an active brickworks. Pond 8 is attached to the Catch Water Drain at the north of site by a culvert. This pond has very steep banks. Pond 9 This pond has no standing water and is now reedbed. Pond 10 This pond is known as the hide pond. It is long and narrow and located adjacent to the mere (pond 11). Pond 11 This is the largest pond on site, known as the mere. A thick reed fringe prevents easy access. In 2012, excavated clay was used to form a peninsula. Pond 12 This was a very shallow rain-fed pond that regularly dried out. Pond 12 dried up completely several years ago and the area is now reedbed. Pond 13 This new pond was dug in 2012; the spoil was used to create a peninsula in pond 11.

6 Amphibian surveys Terry and Helen Moore have run amphibian workshops at the site since These workshops involve casual observation surveys during the day and night (using highpowered torches). Amphibian workshops were run in 2003, 2005, 2009, 2011 and Results from these surveys are presented as simple counts. In 2011, Terry Moore and Martin Baker (Wildlife Trust BCN) developed and trialled a new survey and scoring system based on County Wildlife Site (CWS) criteria. Surveys were conducted using this method during the 2011 season. Results from these surveys are presented as individuals per 2 metres of bank. This survey method will be reviewed in detail in a future report. Pond 1 May 1998 bridge and dipping platform surveyed. 43 GCN and 6 smooth newt Lissotriton vulgaris observed. Multiplied over total area to estimated 250 GCN pairs. GCN spawn found on watercress GCN per 2m of bank smooth newts per 2m. April 4.3 GCN per 2m. 1 smooth per 3.33 per 2m for GCN Only 6 GCN found in a shallow unconnected part of the pond in the southwest corner. Very low numbers for this pond. Pond limited access but 6 GCN Pond no newts but visibility very poor Pond GCN and 7 smooth poor visibility

7 Pond GCN per 2m bank. Smooth newt 0.5 per 2m GCN and 2 smooth Pond 8 GCN were observed here during school pond-dipping visits in October Pond GCN per 2m. 0.5 smooth newts per 2m GCN and 4 smooth newts Pond 11 The mere has never been surveyed due to inaccessibility. It is possible that there is a large newt population in the pond, but there are fish present. Other Ponds No surveys have been conducted at ponds 6, 7, 9, 12 & 13. Ponds 3, 12 and 9 are now dry, so will not be surveyed in the future. Conclusion and Recommendations Great crested newts have been recorded in ponds 1, 2, 4, 5, 8 and 10 at Ramsey Heights Countryside Centre. Observations suggest that newts are using all extant ponds and surrounding terrestrial habitat in the reserve. It is considered that natural habitat succession and the presence of fish in pond 1 has had a negative impact on the great crested newt population. The following recommendations are made: 1. Continue the annual amphibian workshop surveys, reviewing the new scoring methodology. Starting in 2015; 2. Habitat improvement, including pond restoration and hibernation sites. Pond 1 to start January 2015 (see appendix 2); 3. Fish removal at pond 1 to be completed in November/December 2015 by Environment Agency.

8 Appendices Appendix 1 Map of Ponds at Ramsey Heights Figure 4 Map of Countryside Centre with sketched pond shapes and numbers (Terry Moore, 2014)

9 Appendix 2 Pond 1 sketch map and photos Figure 5 Sketch map showing pond 1 habitat in December 2014

10 Photo 1 Photo 2 Photo 3 Photo 4 Photo 5 Figure 6 Photos of pond 1 in December See map for photo references