This year marks the centennial of the Migratory Bird Treaty, an agreement signed in 1916 to help conserve, protect, and manage migrating birds and their habitats throughout the U.S. and Canada. The 100th anniversary is a reminder that such birds play vital ecological roles. They are also good indicators of the health of our environment.

Raptors are among the largest migrators, and up to eighteen species have been recorded in New Mexico’s Manzano Mountains, a north-sound range along the Rocky Mountain Flyway. At the spectacular observation site near Capilla Peak, scientists and trained volunteers with the nonprofit group HawkWatch International identify and count hawks, eagles, and other birds. Typically some 5,000 to 7,000 are tallied each year between late August and early November. The site is on a knife-edge ridge where wind patterns help the birds use less energy during demanding southward migrations.

Some birds are captured, banded, and released to better gauge their health and population trends. More than three decades of annual data reveal that golden eagles, American kestrels, and ferruginous hawks seem to be declining for reasons HawkWatch and other groups are trying to determine—possible causes include loss of habitat and climate change.

The public is welcome to visit the Manzano HawkWatch site, located about sixty miles southeast of Albuquerque.