Many people get turtles, terrapins and tortoises mixed up. It’s not helped by the American habit of calling all turtles and terrapins by one name: turtles. The differences are important: tortoises are land creatures, seldom if ever seen in water whilst turtles and terrapins are aquatic reptiles that live in fresh or brackish water and are seldom seen on land, except when laying their eggs or basking in the sun. The confusion comes from their common factor: an external protective shell, thin and pliable in turtles and terrapins but hard and robust in tortoises.
Terrapins are now often seen in local streams, canals and lakes around Rotherhithe and Bermondsey. They can grow to 30cm in length and live up to 30 years. The female terrapin lays her eggs between April and June producing one or two clutches each season, each of between 4 to 18 oblong-shaped pinkish-white eggs. When they hatch, baby terrapins are only 3cm long and weigh about 8g. They grow to maturity over the following three to eight years with the female terrapins outstripping the males in size. They can grow to weigh 2 kg producing a growth ring on their plastron (the underside) and carapace (the upperside). From these growth rings, you are able to estimate their age.
The population in Rotherhithe has been expanding in recent years. It’s hard to know whether this is due to breeding success or the freeing of unwanted pets into local ponds and lakes. Two possible species may have made their home in SE16: the European Pond Turtle and Diamondback terrapins. Both species are omnivores but in the wild mostly eat live prey such as small fish, worms, snails and insects. They have been noticed in Russia Dock Woodland, around Plover Way, in Albion Channel and in Canada Water.
If you see a terrapin, admire it but leave it alone. They are naturally shy and retiring so avoid any fast movements. The photos here were all taken this year in and around Canada Water so if you pass through there, stop off and take a quiet look on the margins of the lake. In the summer months, they often bask in quiet spots where the sun warms their cold blood. You might just see one for yourself!