Justin Gillis

Some of the 54 species of coral in the Northeast Canyons and Seamounts monument southeast of Cape Cod, Mass. It’s one of 10 national monuments that the Interior Secretary is reevaluating for the White House. (HANDOUT/NYT)

Building a better coral reef

After decades of accumulating damage, followed by a huge die-off in 2015 and 2016, some scientists believe half the coral reefs that existed in the...