White-clawed crayfish

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1 Species Action Plan White-clawed June 2010

2 Table of Contents Species and habitat description... 3 Status and legislation... 3 Current factors causing loss or decline... 4 Non native... 4 Crayfish plague... 5 Porcelain disease... 5 Water pollution... 5 Degradation of habitat... 6 Current action... 6 National Objectives & s... 7 References... 8 Objectives, s and Actions... 9 Objective 1 Map and monitor the extent and distribution of the whiteclawed and non-native... 9 Objective 2 Maintain favourable habitat condition on all known whiteclawed sites in the Sheffield district Objective 3 Ensure the bio-security of white-clawed populations in Sheffield...13 Objective 4 Raise awareness of Sheffield s white-clawed populations and educate the public about how they can help to conserve these populations...15 Key to Delivery Partners:

3 Species and habitat description The white-clawed (Austropotamobius pallipes) is our largest freshwater invertebrate and the only freshwater species native to the UK. The UK supports approximately 24% of the global white-clawed population. White-clawed are classed as Globally Threatened by the IUCN (JNCC, 2007) and have suffered large declines throughout their natural range in Britain and Europe due to factors including water pollution and habitat degradation, the impact of non-native species and plague (Pöckl et al, 2006). White-clawed can live for years and grow up to 12cm in length, excluding their claws. They are brown to olive in colour, while the undersides of their claws are pinkish-white. Their breeding season lasts from autumn to early winter. The females brood the eggs on the underside of their tails over the winter. The eggs hatch in the spring and the young remain attached until they are ready for release from June (in the south) to August (in the north). If disturbed before this time, the females could be caused to release their young too early. White-clawed have been found living in streams, rivers, canals, lakes, reservoirs, water-filled quarries and mill ponds, but they principally inhabit clean alkaline waters with a minimum concentration of calcium of 5 mg/litre and a ph between 6.5 and 9.0. White-clawed require suitable submerged refuges such as rocks, logs, tree roots, algae and aquatic plants. They may also dig burrows into soft sediment, and hide beneath overhanging banks below the water-level. Whiteclawed are omnivorous and eat detritus, invertebrates, carrion, aquatic plants and algae. Status and legislation White-clawed have a widespread but scattered distribution in England, a sparse distribution in Wales, a widespread distribution in Ireland and have two introduced populations in Scotland. The British population of white-clawed is considered to represent the greatest concentration of the species in Europe (Holdich, 2003). Sheffield s white-clawed populations are considered to be of regional importance, with recent surveys confirming that the Porter Brook and Limb Brook, (tributaries of the River Sheaf in the west of Sheffield), and the River Sheaf itself, support good populations of the native. Due to their dramatic decline since the 1970s, white-clawed are protected under European and national legislation, and a number of policies have been implemented to conserve them and their habitat. White-clawed are: A Priority Species in the UK Biodiversity Action Plan. A Species of Principal Importance under Section 41 of the NERC Act

4 Listed under Annexes II and V of the EC Habitats Directive (Council Directive 92/43/EEC) which is effectively implemented in the UK by the Conservation (Natural Habitats, & c.) Regulations 1994 by facilitating the establishment of Special Areas of Conservation (SACs). Listed under Appendix III of the Bern Convention (Council of Europe 1979). Protected under Schedule 5 of the UK Wildlife and Countryside Act 1981 (as amended). Under this Act, it is illegal to handle, take or sell white-clawed. Country conservation agencies such as Natural England issue licences to carry out surveys for white-clawed or to move specimens, for example in relation to maintenance and engineering operations. Under Section 14 of the Act, it is illegal to introduce non-native listed under Schedule 9 of the Act (which includes signal ) into watercourses or water bodies. The following legislation and policies also contribute to the conservation of white-clawed : The Prohibition of Keeping of Live Fish (Crayfish) Order 1996 made it illegal to keep non-native anywhere in England and Wales without a licence, with a few exceptions. A bylaw under the Salmon and Freshwater Fisheries Act 1975 (as amended) has designated no-go areas for the trapping of except from authorised activities; all of South Yorkshire has been designated a no go area. The Act prohibits the use of live or dead, or any part of them, while fishing for salmon, trout, freshwater fish or eels. Environment Agency consent is required for the removal of any species of from inland waters. In an attempt to reverse the continued population decline of white-clawed in England and Wales, a strategy is being implemented to introduce white-clawed to new bio-secure ark sites, isolated sites considered relatively secure against invasion by non-native or contamination by plague. Research is also being conducted into potential measures for protecting white-clawed populations in situ through the modification of natural or man-made barriers to the advance of signal, such as weirs. Current factors causing loss or decline Non native There are six species of non-native present in the wild in Britain today (Holdich and Sibley, 2009), with the introduced North American signal (Pacifastacus leniusculus) being the most widespread species and therefore having the greatest impact on our native population. The signal grows faster, attains larger size, produces more young, and can live at higher densities than the white-clawed (Holdich 2003). It is also more aggressive, and often acts as a vector for the virulent plague to which it is immune. As a consequence, although mixed populations of the two 4

5 species can be found, the white-clawed is generally eliminated within a few years of the arrival of signal through competition or a few weeks if the plague is introduced to the population. At present there is no way to control signal once they have become established in a water body, although research is currently being conducted to investigate the possible use of pheromones and chemical signals as a control method (Holdich, 2003). Trapping and removing non-native is likely to exacerbate the problem, as the individuals most likely to be trapped are large males, who would naturally control numbers to some extent by predating on the smaller individuals (Holdich, 2003). Signal have been identified in a number of Sheffield s streams; this represents a direct threat to the population of white-clawed in Sheffield given the location of the invasive line of signal. Crayfish plague Crayfish plague is caused by the oomycete fungus Aphanomyces astaci, and is transmitted by contact between. The spores may also be carried by fish, on clothing including muddy footwear and on equipment used for recreational activities such as fishing and canoeing. The plague is lethal to white-clawed and total mortality of a population can occur within a few weeks of exposure (Peay, 2000). Crayfish plague has been responsible for a number of mass mortality events in water bodies in the UK (Holdich, 2003). In the absence of any evidence to the contrary, it must be assumed that any signal found in the Sheffield District will carry the plague (Eades, 2008). Crayfish plague was confirmed in the lower reaches of the Porter Brook in October This has not only caused white-clawed mortalities within the affected area of the Porter Brook, but also puts the rest of Sheffield s native populations at high risk of exposure. Porcelain disease Porcelain disease is caused by the microsporidian parasite Thelohania contejeani, which gradually takes over the musculature of the. Infected can function relatively normally for a couple of years before dying (Holdich et al, 2004). Water pollution White-clawed are highly vulnerable to pollution incidents, particularly those that involve biocides such as pyrethroids or organophosphates which are used in sheep dip, and organic pollution including domestic sewage leaks, farm slurry inputs or silage effluent (Holdich, 2003). Sheep dip biocides are lethal at very low concentrations to most invertebrate species such as, while organic pollution can lead to increased ammonia concentrations and reduced oxygen concentrations, both of which can cause significant mortality in white-clawed (Holdich, 2003). 5

6 Degradation of habitat Developments or other operations on or near to a river have the potential to cause habitat degradation, particularly where they result in canalisation, removal of in-channel refuges, use of mortared stone, sheet piling or concrete riverbanks to prevent erosion, extensive clearance of bank side vegetation, or heavy siltation. White-clawed require suitable submerged refuges beneath which they can hide from predators. Many rivers have received some form of modification either historically or in recent times in the form of re-profiling or reinforcing. These operations often remove suitable refuges for white-clawed. Works and land uses in and adjacent to watercourses often cause siltation to occur. This can damage the gills of and reduce the availability of suitable refuges for both adults and juvenile. Large parts of the headwater areas of the river and stream network in south-west Sheffield have unmodified channels that are able to meander, erode and redeposit material freely, creating plentiful refuges for white-clawed. However, where these watercourses flow through built up areas or formal parks and woods, they often have reinforced banks to prevent natural erosive processes from damaging adjacent structures such as houses, roads and bridges. These artificial beds and banks have reduced the availability of refuges for along large stretches of their natural range in Sheffield. In older sections of man-made structures, such as brickwork and stonework on bridges, weirs, dams and canals, crevices can start to appear where may take up residence. Current planning policies in Sheffield no longer encourage the canalisation of watercourses, but repairs to existing artificial riverbanks, weirs, and other riparian development or maintenance work requires careful design and implementation in order to avoid degrading the habitat they provide (Eades, 2009). Current action Crayfish in the Sheffield District report commissioned by the Environment Agency and produced by Phil Eades in The report outlines recommendations for future surveys and actions to conserve white-clawed populations. Recent surveys have found good populations of white-clawed in the Porter Brook, Limb Brook and the River Sheaf. There are records of signal in the Moss and the Shire Brook, and a recent record of a single adult signal in the River Sheaf. The Department of Environment, Food and Rural Affairs (DEFRA) holds the registry of farms and monitors outbreaks of plague. A database commissioned by the Environment Agency is established at Nottingham University to record and monitor the distribution of native and non-native in the UK. 6

7 The Environment Agency area office, Sheffield Biological Records Centre and Sheffield Hallam University hold records of Crayfish in the Sheffield district. White-clawed were rescued from the Porter Brook in November 2009 following an outbreak of plague in the area downstream of Endcliffe Park. After spending the winter in a quarantine facility, the population was translocated to a new ark site in Sheffield in April National Objectives & s The revised national SAP targets for the white-clawed are as follows (BARS, 2010): To maintain the current range of white-clawed in the UK (241 10km grid squares in the UK, 194 of which are in England) Achieve an increase in the range of the white-clawed in the UK (From 59 10km grid squares to km grid squares by 2030) Maintain key populations of white-clawed in the UK (19 key populations identified in the UK, 14 of which are in England) A key population is one which has or merits SAC designation. 7

8 References BARS (Biodiversity Action Reporting System) National Action Plan for whiteclawed 0A3%2D95F6%2D AFB%7D&M=1 Accessed June 2010 Eades, P 2008 Crayfish in the Sheffield District. Unpublished report to Environment Agency, Leeds. Eades, P 2009 Crayfish in the Sheffield District. Unpublished report to Environment Agency, Leeds. Holdich, D.M Ecology of the White-clawed Austropotamobius pallipes. Conserving Natura 2000 Rivers. Ecology Series No.1 English Nature, Peterborough. Holdich, D.M., Sibley, P.J and Peay, S 2004 The White-clawed a decade on. British Wildlife 15 (3) Holdich, D.M. and Sibley, P.J ICS and NICS in Britain in the 2000s. In Crayfish Conservation in the British Isles. Proceedings of a conference held on 25 th March 2009 at the British Waterways Offices, Leeds, UK, (eds Brickland, J, Holdich, D.M. and Imhoff, E.M), JNCC nd report by the United Kingdom under Article 17 on the implementation of the Directive [92/43/EEC] from January 2001 to December JNCC, Peterborough. Peay, S 2000 Guidance on works affecting white-clawed. English Nature and Environment Agency report. English Nature, Peterborough. Pöckl, M, Holdich, D. M. and Pennerstorfer, J 2006 Identifiying Native and Alien Crayfish Species in Europe, CRAYNET. 8

9 Objectives, s and Actions Action Ref # Objective 1 Map and monitor the extent and distribution of the white-clawed and nonnative in Sheffield 1.1 Create and maintain a comprehensive database of the distribution of native and nonnative in the Sheffield district. Share the information with interested parties. Measure 1 database of distribution created by December 2009 and updated annually with new data. Action Collate and review existing survey data for all known populations of native and non-native, identifying gaps in existing survey data and priority areas for further surveys. Implement surveys and monitoring visits on priority areas. Enter all existing survey data related to whiteclawed and signal into the Sheffield Biological Records Centre s Recorder 6 database and GIS files. Enter data gained from new surveys and monitoring visits into the Sheffield Biological Records Centre s Recorder 6 database and GIS files on an ongoing annual basis. Action Measure 100% of known survey data collated and reviewed by May staff days per year surveying or monitoring priority areas for whiteclawed and/or signal 100% of existing survey data to be entered by March % of new survey data from the preceding year to be entered by the end of March each year. Delivery Partners SBRC, CAS EA, SCC, SWT SBRC SBRC 9

10 cont. Create and maintain a comprehensive database of the distribution of native and nonnative in the Sheffield district. Share the information with interested parties. measure 1.1 cont. 1 database of distribution created by December 2009 and updated annually with new data. Disseminate data to interested parties in Sheffield and neighbouring districts within the River Don catchment, including the Peak District, Chesterfield, Doncaster, Rotherham and Barnsley. Identify funding opportunities to support the continued provision of survey work and data management work Data sent to at least 1 contact in each of the 6 districts per year 1 funding application prepared per year CAS CAS 10

11 Ref Objective Ensure that the River Sheaf and the Porter Brook continue to meet their Water Framework Directive target of good ecological status. 2.2 Ensure that key whiteclawed sites are protected and where possible enhanced through the planning system. Maintain favourable habitat condition on all known white-clawed sites in the Sheffield district Measure 2 water courses with good ecological status under the WFD annually to 3 water courses protected or enhanced with regard to whiteclawed habitat Action Continue to monitor water quality of the Sheaf and Porter Brook and investigate any adverse changes to the overall water quality immediately. Subject to funding, carry out a detailed investigation of Combined Sewer Outflows along the Porter Brook, to investigate chronic or intermittent pollution events on white-clawed population. Ensure Sheffield City Council takes into account the habitat requirements of white-clawed and relevant legislation and guidelines when considering planning applications affecting water courses / riparian habitats, and that conditions for the protection of and their habitats are incorporated into consents. Supplementary Planning Documents on Waterway Development and Biodiversity to include appropriate guidelines for the protection and enhancement of white-clawed habitat in Sheffield. Action Measure 2 sites monitored annually until 1 investigation carried out by Proportion of planning applications affecting watercourses reviewed by SCC ecologists annually 2 supplementary planning documents produced by Delivery Partners EA EA SCC SCC 11

12 cont. Ensure that key white-clawed sites are protected and where possible enhanced through the planning system. 2.3 Ensure that SCC-owned land adjacent to watercourses is managed with consideration for the habitat requirements of white-clawed. measure 2.2 cont. 3 water courses protected or enhanced with regard to whiteclawed habitat Proportion of SCCowned sites with consideration for incorporated into their management Through development control, ensure that consent for riparian development includes conditions to enhance habitat for white-clawed (including the creation of ark sites if suitable). Provide a training/information session for SCC planners to ensure continued support for the protection of white-clawed and their habitat through the planning system. Provide at least 3 training/information sessions for SCC staff responsible for land-management alongside watercourses with white-clawed. Proportion of planning consents incorporating conditions for white-clawed habitat creation or enhancement annually 1 training/ information session provided by April training/ information session provided by April 2012 SCC SCC SCC 12

13 Ref Objective Ensure that routine and oneoff watercourse management is carried out in accordance with best practice to avoid the spread of plague 3.2 Minimise the spread of non-native along watercourses in the River Don catchment Ensure the bio-security of white-clawed populations in Sheffield Measure Proportion of works in water courses carried out in accordance with best practice annually. Signal populations limited to 2 watercourses in Sheffield. Action Provide advice on proposed works in watercourses, especially those with a known population of white-clawed or signal. Ensure that works are carried out using best practice to avoid the spread of plague and to minimise disturbance to white-clawed and their habitat. Investigate the potential for existing features (e.g. weirs, waterfalls and culverts with or without additional modification) to act as barriers to the spread of signal and plague on water courses in the Sheffield district. Subject to the results of the study and subject to funding, modify existing features to act as barriers to the spread of signal populations. Action Measure Proportion of works in watercourses consulted on by a ecologist annually 1 study complete by April watercourse feature modified to prevent the spread of signal within the Don catchment by. Delivery Partners SCC, EA SCC, EA EA, SCC 13

14 Create ark sites to insure against the loss of white-clawed from Sheffield, in the event that signal extend their range through the River Don catchment 2 ark sites created, populated and monitored by April 2012 Conduct desk and field research to identify potential lentic and lotic bio-secure ark sites. Establish at least two ark sites within the River Don catchment, populate them with quarantined from suitable local donor populations. Carry out monitoring visits at least once a month for 6 months at each ark site immediately after translocation. Seek to secure resources or qualified volunteers to carry out one survey per year thereafter. 1 study complete by April translocations complete by April monitoring visits by October 2012 CAS CAS CAS 14

15 Ref Objective 4 Raise awareness of Sheffield s white-clawed populations and educate the public about how they can help to conserve these populations Measure Action Action Measure Delivery Partners Increase public awareness of the presence of white-clawed and threats to their survival in Sheffield Proportion of sample of local people aware that whiteclawed are present in Sheffield Provide information or educational activities about at 2 public events annually. Provide 4 volunteer participation opportunities annually Produce 3 media releases or web/magazine articles each year on the subject of white-clawed, the threats they face and the work that is being done to conserve them. 2 public events annually by 4 volunteer participation opportunities annually by 3 releases or articles produced annually until EA, SWT, SCC, EtA & SPRITE SWT, SCC, EtA, SPRITE EA, SWT & SCC 15

16 Increase awareness of the presence of white-clawed and best practice for local conservation of the species amongst owners, users and managers of riparian land in Sheffield Proportion of river users, owners and managers Provide one training or education session each year aimed at recreational river users to inform them about best practice to avoid the spread of plague. Subject to funding, produce a leaflet to advise recreational river users on best practice to avoid the spread of plague. Distribute the leaflet via relevant events and outlets. Provide one training or education session each year aimed at landowners and land managers with a responsibility for managing riparian habitat. 1 training or education session annually until 1 leaflet produced and distributed by 1 training or education session annually until SCC, SWT & EA EA, SCC SCC, SWT & EA Key to Delivery Partners: CAS Crayfish Action Sheffield Project Steering Group (members include EA, SWT, SCC, Peak District National Park Authority and ecological consultants) EA Environment Agency EtA Education through Angling SBRC Sheffield Biological Records Centre SCC Sheffield City Council SPRITE Sheffield Partnership: Rivers in Town Environments SWT Sheffield Wildlife Trust 16

Site Improvement Plan. River Kent SAC. Improvement Programme for England's Natura 2000 Sites (IPENS) Planning for the Future

Site Improvement Plan. River Kent SAC. Improvement Programme for England's Natura 2000 Sites (IPENS) Planning for the Future Improvement Programme for England's Natura 2000 Sites (IPENS) Planning for the Future Site Improvement Plan River Kent Site Improvement Plans (SIPs) have been developed for each Natura 2000 site in England