Migration Surveys

Some population surveys are conducted during the spring and autumn migrations, such as the Mid-continent Sandhill Crane Survey and the Fall Inventory of Mid-continent White-fronted geese.

Mid-Continent Sandhill Crane Survey

Nearly the entire population of cranes gathers in Nebraska’s Platte River Valley during spring migration. A pilot-biologist and observer count birds along established transect lines. Aerial photography of a sub-sample of crane flocks is used to quantify errors and develop correction factors to obtain a more accurate population estimate. A Status and Harvests of Sandhill Cranes report is produced each year.

Cranes on the river during survey. (Credit: Jeff Drahota, USFWS)

Cranes on the river during survey. Jeff Drahota, USFWS

Cranes still on  river at 10 AM. (Credit: Jeff Drahota, USFWS)

Cranes still on river at 10 AM. Jeff Drahota, USFWS

White-fronted Goose Survey

Another example of a migration survey is the Fall Inventory of Mid-Continent White-Fronted Geese that is conducted every September in the Canadian prairie, where the population gathers during the southward autumn migration.

A White-fronted goose on the Tule Lake National Wildlife Refuge. (Credit: David Menke, USFWS)

A White-fronted goose on the Tule Lake National Wildlife Refuge. (Credit: David Menke, USFWS) David Menke, USFWS

White Fronted Goose Fall 2012 Inventory

View past White-fronted goose fall inventory reports