On August 1, 2013, An Post issued a further eight stamps for its Irish Animals and Marine Life definitive series, illustrating Ireland's biodiversity from the seabed to the mountain top. Biodiversity is an all-encompassing term used to describe the variety of all life and natural processes on Earth.
The species featured on Marine Life stamps are: the Cushion Star, the Red Tube Worm, the European Eel and the Common Seal.
The Cushion Star is one of the most common echinoderms found on Irish shores. Its small size (rarely more than 3cm across), and its habit of living under rocks makes it difficult to find. It feeds on barnacles, sedentary worms and other encrusting animals.
The Red Tube Worm thrives on rocks, shells and other hard surfaces in the sublittoral zone or below. Its body has 200 segments with the crown consisting of as many as 70 tentacles and may grow to a length of 7cm.
The European Eel has a fascinating life-cycle that involves an incredible two-way migration across the Atlantic Ocean. It feeds on a wide variety of prey, and will eat almost anything smaller than itself. Females are generally larger than males, reaching lengths of a metre or more and with a maximum recorded weight of 6.6kg.
The Common Seal is a carnivorous hunter with a large and varied diet. It can dive for long periods into deep waters, although in Ireland its dives are generally short and are usually conducted in waters not more than 70m deep. The males are known as bulls and are larger and heavier than the females which are known as cows. Mature bulls can be up to 2m in length and weigh up to 150kg.
The species featured on the Animals stamps are: the Natterjack Toad, the Red Fox, the Great Spotted Woodpecker and the Black-legged Kittiwake.
The Natterjack Toad is Ireland's only toad species and is easily recognized by the yellow stripe that runs down its back. Natterjacks feed on insects, worms and small reptiles. At night they travel considerable distances through open terrain with sparse vegetation, thus enabling it to colonise new habitats very quickly.
The Red Fox has a brownish red coat and a bushy tail tipped with white, and is one of the most common mammals in Ireland. Its territory has expanded well beyond its traditional rural haunts and now includes towns and city suburbs. Red Foxes usually feed on rabbits, young hares, rats and small birds, but they also eat mice, insects and fruit.
The Great Spotted Woodpecker can be found in both broadleaved and coniferous woodlands and forests and recently has been spotted in gardens and parks. They feed on seeds, invertebrates, and occasionally bird eggs and nestlings. During spring they can be heard "drumming"; a sound produced by rapidly pecking on a dead branch or other resonant object.
The Black-legged Kittiwake is a small, cliff-nesting gull, named for its loud, nasal "kitti-wake" call. Its short legs are usually black, helping to distinguish it from the Red-legged Kittiwake. The hind toe of each foot is reduced to a mere bump, meaning it has only three functional toes instead of four, giving the Black-legged Kittiwake its scientific name, tridactyla, which means "three-toed".