Water rail
Water rails are omnivorous, although they mainly feed on animals. These include leeches, worms, gastropods, small crustaceans, spiders, and a wide range of both terrestrial and aquatic insects and their larvae. Small vertebrates such as amphibians, fish, birds and mammals may be killed or eaten as carrion. Vertebrates are impaled with a strike of the bill which breaks the prey's spinal cord. Plant food, which is consumed more in autumn and winter, includes the buds, flowers, shoots and seeds of water plants, berries and fruit. In south Asia, paddy (harvested rice kernels) may sometimes be eaten. The young rails are fed mainly on insects and spiders. Food obtained on land or from mud is normally washed in water before it is eaten. After rain, rails may probe soft ground for earthworms. This species will occasionally feed in the open even when not forced to do so by cold weather; Edmund Meade-Waldo described seven rails feeding in an open meadow. Despite its skulking nature, the water rail appears to thrive in captivity when fed on animal food such as raw meat or earthworms; one individual was taught to jump for worms suspended from a fishing rod.
Stone loach
The larvae of stone loaches are benthic, they and small juveniles prefer sandy substrates with a slower current, as they grow they move on to gravel bottoms and faster currents. As adults they prey on relatively large benthic invertebrates such as gammarids, chironomids and other insect larvae. It normally feeds at nights when it uses the barbels around its mouth to detect its prey. They are tolerant of moderate organic pollution and stream canalization but they are highly sensitive to heavy metal pollution, chemical pollution and low oxygen levels which mean that the presence of stone loaches in a river is an indicator of good water quality. They are short-lived fish, normally living to age 3–4 years with 5 years being exceptional.