Billy Frank Jr., 1931-2014. Photo from Facebook

Billy Frank Jr., a member of the Nisqually Tribe of Washington who defended the treaty rights of tribes in the Pacific Northwest, died today. He was 83.

Frank was arrested about 50 times -- the first at the age of 14 -- for exercising his treaty-protected fishing rights. His struggle helped lead to the historic Boldt decision that secured half of the catch for tribes in Washington.

“Salmon is in our blood. That’s how it is: It’s there, and we want to keep it there,” Frank told KUOW, citing the reason why tribes fought so hard to protect their rights.

As part of his lifelong effort to protect fish habitat and restore fish runs, Frank served as chairman of the Northwest Indian Fisheries Commission for the last 30 years. The organization said it was closed for the rest of the day out of respect for their leader's death.

"It is with great sadness that we must inform you of the passing of Billy Frank Jr. this morning," NWIFC said on its website.

"Indian Country lost a giant today," Keith Harper, an attorney who represented the Frank's Landing Indian Community, a traditional fishing site, and who worked with Frank on a number of issues, said on Facebook.