Tuna Management Act of 1989

Tuna Management Act of 1989 - Amends the Magnuson Fishery Conservation and Management Act to declare that the United States claims and will exercise exclusive fishery management authority over all pelagic species throughout the migratory range of each such species beyond the U.S. Exclusive Economic Zone, except when within any foreign nation's territorial sea or exclusive economic zone as recognized by the United States.

Repeals provisions of such Act providing for the exclusion of highly migratory species of fish from the sovereign rights and exclusive fishery management authority asserted by the United States under existing provisions.

Amends the Atlantic Tunas Convention Act of 1975 to change the composition of the advisory committee established by that Act.