Giant invasive CRABS have been spotted in Teddington's Bushy Park this week.

The Chinese mitten crabs, so-called because of their distinctive furry glove-like coverings on their main claws, have been spotted twice over the last week on the paths in the park.

Experts say they are preyed upon by the herons and crows of the Royal Park which is best known for its majestic herds of Red and Fallow Deer plus a massive assortment of birds, rabbits and insects including the Bushy Park gnat.

Phil Edwards, Bushy Park's manager, told Nub News: "There have been a small number of mitten crabs in the park for a number of years but fortunately these numbers are successfully managed by herons which fed on them, keeping them at consistent low levels.

"Visitors can help us manage the parks delicate ecosystem by not leaving unwanted pets into the park."

It is understood that pet terrapins and even goldfish have been dumped in the park.

Chinese mitten crabs are particularly unwelcome however as they can do damage to fishing gear and river banks by burrowing into them and also compete with native species.

The hairy crab species are officially listed as one of the World's 100 worst invasive species and have carapaces that can grow as large as a dinner plate.

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London's Natural History Museum encourages the public to report their sightings of Chinese Mitten crabs online.

The Museum says: "The full extent of Chinese mitten crab distribution in the UK is unknown, so we are asking the public to help by reporting their sightings."

According to previous reports, Chinese mitten crabs are abundant in the river near the Sandy Lane entrance to Bushy Park and provide an annual feast for crows and other opportunists as they migrate to the Thames in spring.

Nub News discovered an article in the London Naturalist from 2008 called 'The fishes, amphibians and reptiles of Bushy Park, Middlesex' which references the little-known crab species.

The report says: "The Chinese mitten crab is already present in the water bodies of the park.

"It is an omnivorous predator, whose impact on the amphibian and fish populations of Bushy Park is as yet unknown, but it is believed that through predation and competition for resources, as well as its nutrient releasing and habitat altering burrowing activities which may also have an impact on plant diversity, its presence may become increasingly detrimental.

"This species spends four or five years upstream in fresh water, and must return to the saline waters of the Thames Estuary to reproduce.

"It is a measure of the ability of this species to migrate to and from the estuarine environment that it can be found so far upstream.

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"As previously mentioned, it has the ability to invade the entire Thames catchment area, and has certainly spread as far as the River Colne at Staines, 63 km from the sea.

"After many decades of being rarely and sporadically recorded in Britain, the population of Chinese mitten crab increased markedly in the 1990s, and it is believed that this species, which has been placed on the IUCN list of the World's one hundred worst alien species, is capable of infesting all of the Thames and its tributaries."

Report your Chinese Mitten crab sightings here

More on the London Naturalist's Bushy Park report

Have you seen anything unusual in Bushy Park recently? Let us know!