These fields and marshes, 8 miles south of Socorro, are the wintering ground for migratory birds including snow geese, sandhill cranes and bald eagles, though sadly no longer the whooping crane. The season lasts from late October to March, and peaks in December and January. Upwards of 325 bird species and 135 mammal, reptile and amphibian species have been sighted. From the visitor center , a 15-mile loop circles the refuge; hiking trails and viewing platforms are easily accessible.