Using its rasping tongue, known as a radula, the great pond snail feeds on both plant and animal matter, leaving behind distinctive feeding marks (7). It can even attack newts, small fishes, and water beetle larvae and may occasionally be cannibalistic, eating smaller great pond snails (3).
The great pond snail lays large gelatinous egg-masses on weeds and other objects in the pond (6). These egg masses measure between five and six centimetres in length (5), and can contain as many as 50 to 120 eggs (6). The size to which a specimen will grow is dependent upon the volume of water in the pond; individuals grow larger in big ponds. Young specimens are slender and have more translucent shells than mature snails (6).
Although the great pond snail often comes to the surface to take in air into a respiratory cavity, when the pond becomes covered in ice or when the snail moves to deeper water in winter, it is able to take in oxygen from the water through the skin. The wide tentacles play a key role in the intake of oxygen; the surface of the tentacles is covered in tiny hair-like structures known as 'cilia' which function to increase their surface area, thus increasing the intake of air (4).