Fish (salmon) short of some oxygen, caught by a fleet out of area (7)

I believe the answer is:

anchovy

'fish' is the definition.
(anchovy is a kind of fish)

I cannot understand how the remainder of the clue works.

(Other definitions for anchovy that I've seen before include "Small edible fish" , "Small salty fish" , "Small fish used in making sauce, paste etc" , "Little fish, usually tinned or salted" , "Salty little fish" .)

I've seen this clue in The Guardian.

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