Black is a very effective lure color under both cold and warm water conditions. Black is always black and stands out extremely well against a light colored or gray sky or a blue sky. The color blue is always blue up to 550 ft deep. commercial salmon trollers off of Canada's Vancouver island have had good success on blue salmon plugs at great depth for big springs. blue is one of the most overlooked lure colors in the spinner world, with the possible exception of the Blue Fox silver and blue French blade spinner, which is extremely popular and very effective for both steelhead and salmon.