The Guardian-Scientists build traps to manage UKs rising number of Chinese mitten crabs
October 14, 2023 3 min 583 words
这则报道涉及到英国日益增多的中国绒螯蟹问题，由科学家们建造的陷阱，以应对这一挥之不去的侵略性外来物种。这是一个具有挑战性的环境问题，以及科学家采取的应对措施，对此有几点观点。 首先，中国绒螯蟹的侵袭行为已经引起了严重的生态问题，危及了英国的本土物种，特别是淡水鱼类和水生生物。这表明需要采取措施来保护生态平衡和本土生态系统的健康。科学家们采取的陷阱建设是一个重要的措施，希望能够削减绒螯蟹的数量，从而保护本土生物多样性。 其次，该报道突出了科学家的努力，他们试图找到解决这一问题的方法。他们的工作是为了改善环境，减少对本土物种的威胁。这种科学研究和解决方案的应用，为生态保护提供了一个有希望的示范。 然而，应该强调的是，科学家们需要谨慎地执行这些措施，以确保不会对其他生态系统或物种造成不良影响。此外，公众的合作也至关重要，他们可以通过报告绒螯蟹的观察来帮助科学家们更好地了解和管理这一问题。 总之，这个报道突显了生态平衡的重要性，以及科学家们在保护环境方面的努力。这是一个艰巨的挑战，但也是一项重要的工作，可以为英国的自然生态系统带来积极的影响。希望这些努力最终能够改善当地的生态状况。
It is classified by conservationists as one of the 100 worst invasive alien species in the world. Now, a group of scientists are hoping they have found a way to deplete the UK’s rapidly growing Chinese mitten crab population and prevent the crustaceans, which can grow bigger than a 10-inch dinner plate and have distinctive furry claws, from “eating us out of house and home”.
The group has constructed and installed the UK’s first Chinese mitten crab trap at Pode Hole in Lincolnshire, to catch the voracious predators as they migrate downstream to mate.
“The mitten crab are eating our native fauna,” said Dr Paul Clark of the Natural History Museum, one of the scientists working on the project. “If we start capturing these crabs and depleting their population, we might see changes in our environment for the better.”
This could include an increase in the local population of spined loach, a freshwater fish which is reported to have declined at Pode Hall, along with water voles, bivalve mollusks, small shrimp and snails.
The Chinese mitten crab, so-called because it originated in south-east Asia, was first sighted in the UK in 1935. Since then its population has exploded.
“Females can spawn two series of eggs, and they spawn somewhere between 500,000 and one million eggs in one go,” said Clark. “There’s millions in the Thames and huge populations in the Medway, the Ouse Washes, the Dee, Tyneside and the Humber. They are eating us out of house and home.”
He described seeing a mitten crab devouring a snail. “The crab treated it like an ice-cream cone. It nipped off the top, pulled the snail out from its shell – and ate it.”
Similarly, he said, his students have filmed a mitten crab “crushing an amphipod against the underside of its carapace, and with its other claw, it killed the shrimp and ate it”.
Research has shown the crabs also eat salmon and trout eggs – native fish species which are already under threat in the wild.
The scientists plan to freeze the crabs they catch, and then hope to be able to dissect them to find out what they have been feeding on. “If we can, we will do some DNA analysis on the digested guts.”
The “experimental” trap, which has a unique letterbox construction, was designed by Mick Henfrey, a foreman at the Welland and Deepings Internal Drainage Board, and Oscar Jones, a graduate of the Department of Engineering at the University of Sheffield.
Jones came up with the idea for the project after a Chinese Mitten crab was spotted by a member of the Lincolnshire Wildlife Trust climbing over the weir at Pode Hill. “We got together and decided to build a trap and the Environment Agency gave us permission to set it,” said Clark. “It’s like an extended letterbox that goes across the weir, with two openings, one facing upstream and one downstream. We hope they will climb into the letter box and then up a tube.”
He said the trap will be inspected every day and hopes that, if it is successful, other traps can be installed in rivers such as the Dee, an important salmon habitat.
The project is being run in conjunction with the Lincolnshire Wildlife Trust and the Welland and Deepings Internal Drainage Board.
Members of the public are asked to report sightings of Chinese mitten crab online at mittencrabs.org.uk.