Criteria for assessing potential Ark Sites
Crayfish specialists and Buglife have been developing a set of criteria for selecting new Ark sites for White-clawed crayfish conservation. The current format is a MS Excel-based tool and is available to download here. The Ark site selection tool is in the testing phase of development, so we would encourage those who are looking to identify new Ark sites to use this tool and please give us feedback using the form at the bottom of this page.
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| Potential Ark site being investigate in South West England © Kate O'Neill |
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| Crayfish trapping at a potential Ark site © Andrew Whitehouse |
How to use the Ark Site Selection Tool
The selection process has two stages. Stage 1 eliminates unsuitable sites quickly. Sites which pass this initial assessment should then be assessed in finer detail in stage 2.
The second stage involves grading a site using a series of tables, each on a different topic. This process identifies the risks to White-clawed crayfish and guides decision-making based on the threats to crayfish at the site and in the catchment or region.
If, following the assessment, a site is considered to be a good potential Ark site, it can go to the next stages: detailed site investigation, identifying a donor population, obtaining permission from the statutory agencies and securing resources. Once all the essential preparation is done, a stock of White-clawed crayfish can be introduced (subject to obtaining the relevant licences and permissions). If successful, the population will survive and expand in the new Ark site.
Existing populations
The criteria can also be used to assess the risks to an existing population of white-clawed crayfish. If the risks are low it can be considered as an established Ark site. The criteria allows for an analysis of whether any new measures are needed to safeguard it. Alternateively, it may be that a population is under severe threat and in need of a potential ark site as soon as possible.
Download the Ark site selection criteria here.
