Trim carry bags carry W (6)

I believe the answer is:

beluga

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(Other definitions for beluga that I've seen before include "Could a bugle be a source of caviar?" , "Small white whale; type of caviar" , "Large Russian sturgeon" , "'Russian sturgeon, source of caviar (6)'" , "Large sturgeon, source of ..." .)

I've seen this clue in the Sydney Morning Herald.

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