Each year we witness grand tides of migratory life. Cranes rattle overhead; geese wing south from their breeding grounds; tiny warblers rain into coastal brush after battling a headwind on their way north across the Gulf of Mexico. And it is possible through banding programs to follow individuals, to learn in detail their migratory routes.
One of the real pleasures of a winter trip to Bosque del Apache National Wildlife Refuge is the opportunity to contribute to what is known of the wanderings of Snow and Ross’s Geese, by recording the numbers and letters written on any neck collars that we may be lucky enough to see. Banders use particular colors of neck collars for each major nesting colony.
The geese have traditional breeding grounds: Snows wintering at the Bosque are usually from the Western Arctic or Central Canadian Arctic region. Big colonies nest at Prudhoe Bay, Banks Island and Queen Maud Bay. Ross’s Geese traditionally have nested in the Queen Maud Gulf region, with a more recently established nesting colony around the McConnell River in western Hudson Bay.
This map shows the main seasonal ranges of Lesser Snow Geese and Ross’s Geese in the western Central Flyway. It is based on a map in an article, “Status of Lesser Snow Geese and Ross’s Geese wintering in the Interior Highlands of Mexico,” by Rod Drewien, Alberto Lafon Terrazas, John Taylor, Manuel Ochoa Barraza and Ruth Shea, published in the Wildlife Society Bulletin in 2003.
As we scan the masses of white geese with our scope, we find on Snow Geese the black-writing-on-yellow collars of geese banded at Queen Maud Bay and the white-writing-on-black collars of geese from Banks Island. Waterfowl biologist Rod Drewien tells us that on very rare occasions, he finds at Bosque the red collars of birds banded on Wrangel Island. Those are becoming very scarce, since the Russians have stopped their banding program, so only the older birds still wear the red collar of Wrangel.
Snow Goose 5-1V allows me to take a distant photo through the scope. After some research, Rod tells me that 5-1V is a female banded in the year 2000 at Queen Maud Bay. In subsequent years, she has been reported up and down the flyway, and this is the second year that Rod has seen her here at Bosque del Apache.
Banding studies have revealed that families from the multiple nesting colonies of Snow and Ross’s Geese head south, then mix with families from other colonies on the wintering grounds. The young geese form their pair bonds on the wintering grounds, and the young male then accompanies the young female back to her natal colony to start a family of their own. A constant, strong genetic mixing is the result of this pairing strategy.
So the next time you are enjoying the spectacle of a blizzard of white geese, watch for neck collars! If you are able to read the numbers and letters, make a note, and report it to wildlife refuge personnel. You’ll be helping to map the wanderings of a bird like 5-1V!
