When the Mariana crow calls, it’s taken as a warning.  To the Indigenous CHamoru people of the Mariana Islands, the bird is known as the Åga, an ancestral messenger who alerts the community of impending illness or weather disaster. In the dense canopy of Rota’s limestone forest, where the Mariana crow lives, it is a gardener — a key seed disperser from which the lush canopy grows.  According to the US Fish and Wildlife Service, the species is endemic to Guam and the nearby island of Rota, a US territory, which means they live nowhere else on Earth. They once numbered in the thousand...