The powan (Coregonus clupeoides) is a kind of freshwater whitefish endemic to two lochs in Scotland, Loch Lomond and Loch Eck. It has been successfully introduced in two other sites, Loch Sloy and the Carron Valley Reservoir.

Powan populations are relatively healthy, but may have been negatively impacted by the introduced ruffe, which eats powan eggs and fry. As a conservation action, an attempt to establish populations in four additional lochs has been undertaken.

The taxonomic status of the British whitefish populations, including powan, is a matter of debate. Currently the Scottish powan, along with the Welsh gwyniad known from a single lake, and four similar populations in England known as schelly, are generally considered belonging to the widespread Eurasian common whitefish (Coregonus lavaretus). This accords with the close genetic similarity among these units, and the absence of clear morphological differences between them. FishBase and the IUCN continue to recognize the Scottish powan as a distinct species, Coregonus clupeoides.

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