The new three-issue Post & Go series by Royal Mail for 2013 is dedicated to creatures great but small living in freshwater. The first set, seen here, shows lake life, the first life in ponds, and the third reveals the denizens of rivers. The Lakes set showcases Perch, European Eel, Crucian Carp, Caddis Fly Larvae, Arctic Char and the Common Toad.
The stamps are designed by Kate Stephens and the vibrant illustrations are by Chris Wormell.
Perch (Perca fluviatilis): commonly known as the European perch or just perch, is a predatory fish found in Europe and Asia. The species is popular with anglers and has been widely introduced beyond its native area, into Australia, New Zealand, South Africa and elsewhere. They have caused substantial damage to native fish populations in Australia.
European Eel (Anguilla Anguilla): can reach (in exceptional cases) a length of 1.5 m, but is normally much smaller, about 60–80 cm. Eels spawn and then die in the Sargasso Sea. The larvae drift towards Europe where they enter river estuaries as glass eels and migrate upstream. After entering fresh water glass eels grow into miniature versions of the adult eels called elvers. They grow for between 5–20 years in fresh water. As they become sexually mature their eyes grow larger, their flanks become silver and their bellies white in colour. At this stage the eels are known as "silver eels", and they begin their migration back to the Sargasso Sea to breed.
Crucian Carp (Carassius carassius) is a member of the carp family, the Cyprinidae. It is a European species and its wide range spans from England to Russia, living in lakes, ponds, and slow-moving rivers. The crucian is typically 15 cm in body length, and rarely exceeds 1.5 kilograms in weight. Young fish are golden-bronze, but darken with maturity to a dark green back with deep bronze upper flanks, and gold on the lower flanks and belly with reddish or orange fins, although other colour variations exist.
Caddis Fly Larvae: the caddis flies are small moth-like insects having two pairs of hairy membranous wings. They are closely related to moths and butterflies. Caddis flies have aquatic larvae and are found in a wide variety of habitats such as streams, rivers, lakes, ponds, spring seeps, and temporary waters. The larvae of many species make protective cases of silk decorated with gravel, sand, twigs or other debris; others live without a case.
Arctic Char (Salvelinus alpinus) is a member of the salmon family, native to Arctic, sub-Arctic and alpine lakes and coastal waters. It breeds in fresh water, and populations can be either landlocked or anadromous, migrating to the sea. No other freshwater fish is found as far north. It is one of the rarest fish species in the UK, found only in deep, cold, glacial lakes, mostly in Scotland and Northern Ireland, with a few populations in England and Wales.
Common Toad (Bufo bufo) is found throughout Europe. Toads usually lie hidden during the day, becoming active at dusk and spend the night hunting for the invertebrates on which they feed. They move with a slow ungainly walk or short jumps. Their skin is greyish brown and covered with wart-like lumps.