TERRAPINTERRORfor UKPONDLIFE
TERRAPINTERRORfor UKPONDLIFE
Many canals and ponds have something other
than birds on which to focus your binoculars
– terrapins from the USA – and these
unwelcome newcomers are wreaking havoc
with our native pond life. Michael Edwards reports
Terrapins are to be found in ponds and canals throughout the country. The species most imported is the North American red-eared terrapin (Trachemys scripta elegans) though other species such as the common snapper (Chelydra serpentina) from North America and Asian species are also brought in.
What were bought as cute little discs no bigger than milk bottle tops, following the Mutant Ninja Turtle craze, were quickly dumped into ponds when it was realised just how big red-necked terrapins can grow. At the height of the craze, 7million terrapins a year were imported from American terrapin farms, earning them the name, "dime turtles".
A survey undertaken by the National Terrapin Survey (NTP) with support from the National Rivers Authority (NRA) to look into their numbers and spread, concluded that 80% of ponds contain at least one terrapin. In the first year, more than 150 sites were reported from Cornwall to Cumbria and a staggering 150 were counted at one Cardiff location.
More than 20 sites were located in London alone, in park ponds and lakes. Most sites hold a couple of terrapins, and (NTP) co-ordinator Trevor Weeks is concerned that some sites might actually have many more than reported. "On liaising with local residents and authorities, we discovered many more animals, so our initial figures could be increased by 50%."
* No predators
Terrapins have no natural predators here and attack other water life like frogs, newts, fish and their eggs. Even the eggs and nestlings of water birds like coot, water rail, moorhen and dabchick are at risk. Being omnivores, many fear terrapins have led to the decline or even local extinction of some species, including the rare great crested newt. At one site there had been an increasing number of birds, mostly coot, with injured legs. The vet who treated them suspected terrapin attacks.
"Red-eared terrapins like to use the nests of water birds for sun-bathing, crushing the eggs in the process," says Mr Weeks. "We have also had reports of them dragging moorhen and little grebe chicks under the water to drown them before eating them. They have even been seen clambering about in a swans nest."
Types of snapper terrapins, known as snapping turtles, have also been discovered in British ponds. A colony of up to 24 alligator snappers has been reported from one site in West Sussex.
According to Leigh Johnson, keeper of amphibians and reptiles at Southport Zoo, common snappers have even been dumped into the River Thames and red-ears have been spotted in Southports Marine Lake.
* Fast strikers
He adds: "Red-ears cant be considered dangerous but snappers can, lying at the surface on tree roots or amongst weed with just their eyes showing like an alligator. No-one would guess they are there. They may look slow and lethargic, but they can strike as fast as a cobra. It seems amazing that it is still legal to sell these potentially dangerous animals in pet shops. The public just arent warned how big they can grow and the problems will continue so long as they can be picked up in high street pet shops."
The largest snappers grow up to a metre long and weigh around 89kg (200lb). Although generally shy, they can be dangerous and should be left well alone. They have been known to take off an enquiring finger with one bite.
The animals like to come ashore to sunbathe. The best time to observe them is during warm sunny weather when they may be seen basking on logs and rocks above the water. Most red-ears are quite shy and will quickly dive if you make a noise or move suddenly.
The discovery of at least three in my local pond has reinforced my conviction that measures must be taken to protect our native wildlife. If you discover terrapins in your ponds, contact your local Wildlife Trust or FWAG.