The fact that there are plenty of alternatives to the Nimrod to carry out the fisheries side of things is true. However, what's really been missed here is the fact that the same airframes don't have much of a bomb-bay to carry air to ground missiles or torpedoes and their wings aren't really up to carrying Sidewinders/Paveways etc. Anti-submarine warfare was after all, one of our priorities. This will surely come back to bite us in the ar5e.
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