Water Resistant Digital Calipers Measure Crayfish for Native Species Program at Paignton Zoo

 

Bowers Group has recently supplied Paignton Zoo in Devon with Moore & Wright Water Resistant Digital Calipers  to accurately measure white-clawed crayfish. Keepers needed an accurate, waterproof method of measuring the crayfish in order to closely monitor their growth and development, hopefully ensuring the successful breeding programme.

Dr Katy Upton, Senior Keeper, Lower Vertebrates & Invertebrates Department at Paignton Zoo said: “We use the Moore & Wright Plastic Dial Calipers because we like the ease of reading the measurement from them. They are so simple and straightforward that it’s easy for lots of different people to use them, and still get the same result. They’re so simple to read.”

Water and Dust Resistant Calipers

calipers-measuring-crayfish

Paignton Zoo houses two big vats which hold about 1200 litres of fresh water and around 70 native British crayfish. These crayfish came from berried (egg bearing) females taken – temporarily – from a site on the River Culm in East Devon. The river has signal crayfish on it, though luckily there is no crayfish plague at present. The plan is to release the Zoo crayfish higher up the Culm catchment. The white clawed crayfish is protected by law and is recognised as Endangered by the International Union of Conservation of Nature (IUCN).The calipers are water and dust resistant to IP54 specification, have a patented ceramic capacitive sensor, and facilitate 4-way measurement with a thumb wheel for fine adjustment. Kate added: “The calipers give us very precise measurements, which for such a small animal is essential for monitoring the healthy growth and development of a species. They give us nice accurate results every time! They are perfect for our work with the native crayfish. We need to measure them regularly, and the water resistance is especially handy!”

Extinction Threat for Native Crayfish

The Whitley Wildlife Conservation Trust, based at Paignton Zoo, has teamed up with Bristol Zoo Gardens to help the white-clawed crayfish; a native species under threat from its bolder American cousins. The white-clawed crayfish (Austropotamobius pallipes) is the largest freshwater invertebrates in the UK, but is under threat of extinction in the wild because of the introduced American signal crayfish, which out-competes its British counterpart for food and can carry a killer plague.

The crayfish is a shy, reclusive species that few people know about, but it has an important role in the freshwater ecosystem because of what it eats and what in turn eats it. The species is also an important indicator of good water quality. There are only two rivers left in Devon where you can find this species in the wild. There are populations elsewhere in England and on the Continent, but it is in severe decline in many parts of its range.

The Culm Community Crayfish Project

Paignton Zoo previously trialled work on native crayfish with the Environment Agency and the charity Buglife, but this new phase has a greater capacity and the potential to breed. The Zoo, with partners Bristol Zoo and ecologist and crayfish specialist Nicky Green, is working with the Culm Community Crayfish Project.

These crayfish came from berried (egg bearing) females taken – temporarily – from a site on the River Culm in East Devon. The river has signal crayfish on it, though luckily there is no crayfish plague at present. The plan is to release the Zoo crayfish higher up the Culm catchment. The white clawed crayfish is protected by law and is recognised as Endangered by the International Union of Conservation of Nature (IUCN).