lagotis) is smaller and with a less expanded body whorl than that found in Britain This is a Northern Ireland Priority species and has been red-listed as Vulnerable in Ireland (Byrne et al., 2009).Irish specimens approach the appearance of the much commoner Radix balthica or wandering snail and require careful examination. The form found in Ireland differs significantly from that found in Britain and, instead of a broadly expanded aperture with strongly reflected lip, it is smaller, less expanded with the lip barely reflected. Radix auricularia is widespread across the Palaearctic region and can be very variable in appearance. In Britain also there is little evidence of decline. It is certainly still common in Upper and Lower Lough Erne and is widespread on Lough Neagh and its feeder streams, wherever conditions are suitable. It is evidently uncommon and declining in southern Ireland but the situation in Northern Ireland appears different. The great pond snail is absent from moor regions, as there is no limestone with which to form the shell.The ear pond snail is a moderately large water snail with a much expanded body whorl and tiny spire which can be seen gliding over weeds and algae in larger streams and lakes. If the pond should be in danger of drying out, the snail will dig itself into damp mud and can thus survive an arid period. The great pond snail may live up to four years. They may be up to 65mm long and contain up to 300 eggs. The gelatinous egg masses are ribbon-like and often attached to a surface. Great pond snails are hermaphrodites but are capable of self-fertilisation. Small stones may also be ingested in order to help facilitate digestion in its muscular stomach. Remarkably, it may even resort to cannibalism, eating the eggs other snail species. It may also feed on carrion and smaller animals (bryozoa, for example). The great pond snail uses its rasping tongue to feed on algae, plants and all organic matter floating or sinking in the waters. When threatened, the snail exhales the air quickly and can thus sink to the bottom of the pond. With the help of the air in its lung cavities, the snail is able to remain suspended in water. In its natural habitat, the snail uses its foot to crawl to the water's surface, either to feed or to replenish the air in its respiratory cavity, the latter activity lasting around 15 seconds. The great pond snail is not endangered in Austria and is classified as Least Concern (LC) on the IUCN Red List.Īs the scientific name Lymnaea stagnalis would imply, the great pond snail prefers stagnant to slow-moving waters with lush vegetation and is quite tolerant of nutrient-rich environments. In the Donau-Auen National Park, the snail may often be found in the backwaters regularly replenished with groundwater. It is most commonly observed in large ponds, water-filled ditches and rivers in flatland areas. The great pond snail may be found across all of Europe and as far north as Norway.

The snail's body cannot be retracted fully into the shell the wide, oval foot must remain, unprotected, slightly outside the entrance. The relatively small eyes are set on the bulges of the feelers. Like the upper side of the snail's body, these tentacles are also covered with small bright specks. Well circulated, the feelers are used by the snail to breathe, taking in oxygen from the water. Its typically long, flat, triangular feelers look like little horns. The umbilicus around the middle of the shell is sealed. The shell is dark brown, delicate and exhibits fine growth lines. Its shell, which is slender with a pointed spire, can grow to 54mm high and 27mm wide, and the last of the 6-8 whorls are wider and bulbous. Lymnaea stagnalis is one of the largest native freshwater snail species. But in the winter – except for during especially hard frosts – the snail can also be seen near the surface, under a sheet of ice, because it can absorb oxygen through the water into its skin. In order to breathe, the snail regularly comes to the surface of the water to take in air. The great pond snail is active all year round.

Pond snail