Migration of sandhill cranes, Grus canadadensis, in east-central Alaska, with routes through Alaska and western Canada.

Abstract

Some 150 000 to 200 000 sandhill cranes migrate through the upper Tanana River Valley of E Alaska, primarily from the last week of August to the first week of October and from the last week of April to the middle of May. These cranes summer throughout most of interior and W Alaska and in NE Siberia, and they winter mostly in E New Mexico-W Texas and adjacent N Mexico. Except for periods of bad weather, ground use is primarily for overnight roosting and feeding. Open areas are selected for roost sites, with a preference shown for alluvial islands of wide, braided riverbeds. Timing and specific routes are affected by weather, especially strong winds and poor visibility. Cranes are primarily daylight, fair-weather migrants, but sometimes migrate at night and during inclement weather. Most migration occurs between 300 and 900 m AGL, with flights higher in spring than fall. -from Author