Crayfish are a source of local food!
There are six non-native species of crayfish in England and Wales but the American Trigger Crayfish is widely established in British rivers, canals lakes. This crayfish is larger than the native species and has destroyed the natives in many places.
In the south of England the native crayfish has totally disappeared. In addition to the destruction of other crayfish the trigger crayfish excavates burrows in the banks of the rivers etc in which it hibernates in winter. It returns to activity when the water temperature rises above 10C. The damage caused by its excavations and these are a major concern to river authorities.
It has been established that the crayfish is living in both the river Loddon and the Basingstoke Canal. Access to river and canal are restricted and permission will need to be sought from land owners or others with fishing rights. Local fishing clubs maybe able to help with gaining access or give advice who could give access.
Approval from the Environment Agency is required to take crayfish from a river with details of where, when and why you wish to catch them, the species to be trapped and the type and number of traps to be used. The type of trap to be used is strictly controlled and when approval is received tags which are to be fixed to the traps and a catch report form will be provided. The need to have special traps is so that the large trigger crayfish will be trapped whereas the other, smaller species, if any, will be able to escape. An accurate record of how many crayfish which and where they were caught must be kept and at the end of the period of consent the catch report form must be returned to the Environment Agency.
Formal details on approvals and permissions is available from: https://www.gov.uk/guidance/permission-to-trap-crayfish-eels-elvers-salmon-and-sea-trout
More in depth information is available here: Crayfish and River Users Booklet_Web Version2.pdf
We are interested to hear from anyone who has experience of catching crayfish from the Lodden or Basingstoke canal.
Update January 2018
Incredible Edible would like to thank the Hampshire and Isle of Wight Wildlife Trust for providing the following additional information:
The white-clawed crayfish Austropotamobius pallipes is the only species of crayfish native to the UK.
White-clawed crayfish were once widespread across Europe and Britain, but following a dramatic decline during the mid to late 1900’s, are now considered to be internationally and nationally endangered.
There are currently seven species of non-native crayfish established in the wild in the UK, two from Europe (noble and Turkish crayfish) and five from North America (signal, spiny-cheek, virile, red swamp and white river crayfish); however, the signal crayfish Pacifastacus leniusculus is the most widespread and abundant of the these species by a considerable degree.
There have been two other species of freshwater crayfish recorded in the aquarium trade, one currently legal for sale (redclaw crayfish) and the other illegal (marble crayfish); the occurrence of the latter highly is concerning given its ability to breed asexually.
The most significant factor in the decline of our native crayfish has been the introduction of non-native crayfish species in particular signal crayfish, and the disease ‘crayfish plague€’ carried by species from North America, which results in up to 100% mortality in populations of our native species.
Crayfish plague is caused by the fungal-like pathogen Aphanomyces astaci, and can be transferred between watercourses without the transfer of infected crayfish, as the spores can survive on damp equipment and footwear (such as contaminated crayfish traps, angling equipment and boots) for a number of days. It is therefore important that River Users are aware of the need to protect our native species by implementing the appropriate biosecurity measures -- more information can be found here.
Although most existing populations of white-clawed crayfish are concentrated in northern and central England, a number of populations of native crayfish do still exist in southern England including two populations in Hampshire (though one is small and highly localised). These are located on the rivers Itchen and Test catchments.
Signal crayfish can cause significant damage to banksides through the burrows they create, which they may utilise all year round, but can also have significant impacts on fish, amphibian and invertebrate populations also.
Despite the message often advocated in the media, there is no proven conservation gain in the capture of signal crayfish for personal consumption. However, it is the desire to source food locally which most inspires many to catch crayfish locally.
It is important to highlight however that, where conducted inappropriately or at poorly selected locations, trapping for crayfish can in fact have a negative impact on native crayfish and wider biodiversity in a number of ways.
Although many of the crayfish in our rivers today are non-native, the surviving population(s) of native crayfish are vulnerable to people accidentally catching them when out fishing for non-native crayfish species.
If the correct biosecurity measures are not implemented, there is also the risk that people trapping crayfish will spread crayfish plague.
In some situations, there is evidence that trapping can make the problems associated with non-native crayfish much worse. Trapping tends to catch the larger crayfish, usually aggressive males. Crayfish are cannibals, and the larger crayfish can hold back the speed of growth of non-native crayfish populations.
It is considered that native crayfish have been eliminated from the Loddon and Basingstoke Canal and therefore it is unlikely that, if people trap at one or a few locations on these watercourses and implement the appropriate biosecurity measures, a trappers activities will pose a risk to native crayfish. It is vitally important that trapping in other locations is founded on solid local knowledge of the local situation; otherwise real damage might be done.
it is really important when anyone is considering starting crayfish trapping they speak with the relevant Environment Agency Officer. It is important to note that the specific guidelines on the traps are in fact largely to protect species such as otters, water voles and waterfowl becoming trapped and drowning within the trap and that all crayfish trap sold in the UK likely to have the potential to catch adults of all eight (one native and seven invasive) crayfish species present in the wild in the UK. It is therefore essential to note that you need a licence from Natural England to catch white-clawed crayfish, and should anyone catch native crayfish in an area already known to support this species without such a licence, this may constitute a criminal offence under the Wildlife and Countryside Act 1981 (as amended)