Chinese sleeper feeds on plankton at first, after it begins to eat smaller fish (including its own species), amphibians (frogs and newts), and invertebrates.
Chinese sleeper feeds on plankton at first, after it begins to eat smaller fish (including its own species), amphibians (frogs and newts), and invertebrates.
Growing up to 25 cm long, the Chinese sleeper feeds on plankton at first, but once it reaches 10 cm in length, it begins to eat smaller fish (including its own species), amphibians (frogs and newts), and invertebrates.
The Chinese sleeper (Perccottus glenii) is native to the Far East, but it was introduced to the ponds around Saint Petersburg about a hundred years ago. From there, the Chinese sleeper has spread to the Baltics as a dangerous alien species. The Chinese sleeper was first discovered in Estonia in 2005 – in the Narva reservoir and surrounding ponds. It is a predatory fish species that significantly changes natural water ecosystems in its new areas of distribution, reducing the biodiversity and number of local fish, invertebrates, and amphibians. The Chinese sleeper is highly adaptable – it tolerates pollution, lack of oxygen, the freezing of water bodies (surviving even when frozen in ice), and drier periods (by burrowing into wetter bottom sediments). It has been possible to stop the spread of the alien species in ponds with the help of fishing and larger predators, and it has not yet spread south of the Narva reservoir.
Additional information:
Tambets, M., Järvekülg, R., 2005. ‘Uus kutsumata külaline meie vetes – kaugida unimudil’ (A new uninvited guest in our waters – the Chinese sleeper). Eesti Loodus 7/2005. (http://www.eestiloodus.ee/artikkel1170_1150.html)
Environmental Board, 2010. Narva jõgi. Hoiualadega jõed Virumaal 2 (River Narva. Rivers with special conservation areas in Virumaa 2). Tallinn, 176 pages