UK populations of the little known, and endangered Fairy shrimp (Chirocephalus diaphanous) are under threat after 2011's unusually dry autumn affected the ponds in which they live according to the wildlife charity, Pond Conservation.
The charity has warned that the dry weather of the last 12 months, that has left some areas of the country still under drought restrictions, has led to many of the shrimps' favoured pools drying out completely, while equally worryingly other sites are holding water permanently meaning fish can colonise them, eating the shrimps.
Pond Conservation hopes that the species, which is protected under the Wildlife and Countryside Act, will begin to return to its strongholds on Salisbury Plain, in Hampshire's New Forest, on the edge of Dartmoor in Devon and in parts of the Sussex Weald, as well as Oxfordshire, East Anglia and South Wales over the Christmas and New Year period, as dormant eggs hatch in temporary pools filled by the wet weather.
Fairy shrimps are tiny, almost transparent crustaceans which are generally found in small, 'transient' pools such as those created on farmland by tractors and livestock, and look very similar to the Brine shrimp (Artemia sp.) sold as fish food in the aquarium trade.
The filter feeding shrimps live out their short lives during the coldest part of the year, hatching and breeding in just a few months before they typically die in late spring as the pools dry out. Their eggs then remain dormant in the dry pools, with some hatching if the pool fills again, while others remain dormant in case the pool does not persist long enough for the shrimps to complete their lifecycle.
Eggs can also be transferred to new pools by livestock and vehicles and can remain dormant for several years if suitable conditions do not occur.
Changing weather patterns, in combination with pollution have impacted on the shrimps' numbers in recent years, but Pond Conservation has been making new seasonal clean water pools near to existing habitats to try and increase their numbers.
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