Length: 27-32 in Weight: 3.5-7 lbs
Snow Geese come in two color morphs, but can have coloration anywhere in between these extremes.
The white morph is solid white except for black wingtips and pink bill/feet.
The “blue” morph is mostly dark gray/brown, with variable amounts of white usually on the head and undertail.
Breeds in far northern Alaska and Canada. In winter, present in small pockets along the Pacific coast, Midwest, Mississippi basin, and East Coast .
A single gene controls the dark coloration in Snow Geese, and it is partially dominant over the white gene. If two dark geese mate, they may have a mixture of dark and light goslings.
Goslings are precocial, meaning they are relatively mobile and well-developed upon hatching. A Snow Goose gosling may walk up to 50 miles in the first three weeks after hatching as they follow their parents in search of food.
I’ll confess: I have a special place in my heart for Snow Geese. The massive flocks that gather on the arctic tundra in summer are, to me, one of the most awe-inspiring spectacles in the natural world. When I think about what initially got me interested in ornithology, this clip from Planet Earth always jumps to the top of the list.
Fresh off the (scientific) press:
Like many game birds, Snow Geese populations declined significantly in the early 1900s due to over hunting, resulting in a hunting ban in 1916. However, due in large part to the food provided by expanding agricultural land, Snow Goose populations rebounded so tremendously that there are now concerns over them being too abundant.
How abundant is too abundant? For over a decade, scientists have seen evidence that massive goose populations breeding in the arctic are overgrazing their food resources, resulting in degradation of the already sparse tundra vegetation (Jeffries et al. 2004). More recently, Lamarre et al. (2017) looked into the cascading effects this overgrazing could have on other birds that breed on the tundra, and found that in areas where large goose colonies occur, there tend to be more predators and fewer nesting shorebirds.
On the one hand, the explosion in the Snow Geese population is a conservation success story, demonstrating how much a species can benefit from good habitat and protection from market hunting. On the other hand, Snow Geese are now a huge management challenge and a reminder that conservation is about far more than just saving rare species: it’s about promoting a delicate balance among many interacting species in environments that may fluctuate dramatically across time.
Make your own bird cookies!
Jeffries, R L, R F Rockwell, K F Abraham. 2004. Agricultural good subsidies, migratory connectivity and large-scale disturbance in arctic coastal systems: a case study. Integrative and Comparative Biology 44: 130-139.
Lamarre, J-F, P Legagneux, G Gauthier, E T Reed, J Bety. 2017. Predator-mediated negative effects of overabundant snow geese in arctic-nesting shorebirds. Ecosphere 8: e01788.