Waterfowl invasion at Market Lake

While studying 400-plus Tundra and Trumpeter swan at Market Lake on Pond #3, I heard the familiar sound of snow geese. Barely visible to my naked eye, I watched 700 – 800 drop out of the sky to join their cousins on the melting ice.

The spring bird migration has begun with swans, geese, ducks, coots, Red-winged blackbirds, sandhill cranes and Great-blue herons appeared in the Upper Snake River Valley. Flocks of killdeer and Wilson snipes have also joined the few die-hards that spent the winter here.

If you want to watch some real live shows, it’s time to check out Market Lake near Roberts, Mud Lake and Camas National Wildlife Refuge. A drive through the Osgood area could also be rewarding.

“Today (Thursday) is the first time we have seen any snow geese this year at Market Lake,” Robert Akins, a senior wildlife technician for the Idaho Fish and Game Department, said as we watched them settle down. “We have also had thousands of pintails feeding on the standing grain near the headquarters.”

I have fielded comments about snow geese and swans the past few months. One comment I’ve heard from many people is,

“The old potato fields are full of snow geese this winter.”

Snow geese do not spend the winters here nor do they nest here. The only big white bird found in southeastern Idaho during the winter is the Trumpeter swan.

The easiest way to tell the difference between snow geese and swans is that snow geese have black wing tips and the swans do not.

As you watch the flocks of snows as they get close to you, you will see size and color variations in the flocks. The smaller geese, about half the size of the larger ones, are Ross’s geese. The large flock I saw on Thursday had a few of them. They have a shorter, stubbier neck and a much smaller head. The dark colored ones with a white head are “blue-morph” snow geese. Thursday’s flock had three of them. Both Ross’s and snow geese have this different coloration.

The difference between Trumpeter and Tundra swans are easy for experienced birders but can be difficult for beginners. The size, the bill and the calls make it easy for me to distinguish between the two.

When in a mixed group of the two, the Trumpeters are much larger with a longer neck. The Trumpeters have a larger bill that runs in almost a straight line from the tip of the bill to the top of the head which also includes their eyes. The Tundra’s bill is shorter and slightly dished on top that does not include the eye, but has a yellow spot in front of the eye. Experts claim that about 10- percent of Tundra’s do not have the yellow dot.

My favorite way to identify the difference between the two species is with their voice. The Tundra’s have a soothing, soft bugling sound which is much higher in pitch than the repeated “honk” or “toot” of the Trumpeter. You can hear the difference between the species long before you can visually identify them.

Add to all the white birds–a Great blue heron with a funny colored head and sandhill cranes calling and dancing for one another, along with ducks, coots, hawks and Canada geese pairing up–you can have quite a show. A slow drive past the melting ice ponds with new arrivals every day will pull me multiple times to these wonderful marshlands.

The Tundra swan will move north in a week or two while snow geese will spend about a month here and may reach a population of 50,000 here as they rest for their journey north.