Most animal species do not reproduce before a certain age and cannot reproduce after a certain age (Dempster 1975). Understanding the age at first breeding is essential to the study of population dynamics (Caughley 1977). Studies have shown that Sandhill Cranes (Grus canadensis) typically first breed at 3 or 4 years of age (R.C. Drewien, unpubl. data; Littlefield and Ryder 1968; Walkinshaw 1973).
Here, we describe nesting in 1985 by a 2-year-old Greater Sandhill Crane (G. c. tabida) on Modoc National Wildlife Refuge (N.W.R.), California.