Occurrence | endemic | ||
Importance | Ref. | ||
Aquaculture | Ref. | ||
Regulations | Ref. | ||
Freshwater | Yes | ||
Brackish | No | ||
Saltwater | No | ||
Live export | |||
Bait | No | ||
Gamefish | No | ||
Abundance | Ref. | ||
Comments |
Known from lakes Zürich and Walenstadt. At present there is a homogenous population in Lake Walenstadt which spawns October - November. Fifty years ago, there were two populations, one spawning July-September and the other December-February. The winter-spawning population is said to have appeared in 1899. It has been hypothesized that displacement of spawning grounds, changes in temperature, and possibly invasion by a species from Lake Zürich resulted in a hybrid population (involving 2 or 3 species), which is now stabilizing after severe environmental problems which impacted the lake at the beginning of the 19th century (Ref. 59043). |
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States/Provinces | |||
States/Provinces Complete? | No | ||
National Checklist | |||
Country information | https://www.cia.gov/library/publications/resources/the-world-factbook/geos/sz.html |