By PATRICK WHITTLE
PORTLAND, Maine (AP) — A customs dispute at the U.S.-Canada border is threatening America’s supply of a key fish used for popular products like fish sticks and fast food sandwiches. The Alaska pollock has a complicated supply chain. After being caught, it’s transported by ship to New Brunswick, Canada, near the border with Maine. Then it crosses into the U.S. on trucks. The U.S. customs and border agency alleges that shippers are violating the Jones Act, which requires that goods shipped between U.S. ports be transported on U.S.-owned ships. The dispute has left 26 million pounds of fish in cold storage in Canada.