If you are doing outside activities in the Chippewa Valley
anytime starting in mid-March through April, you may see or hear swans flying high
overhead. Given the time of year these will most likely be the migrating Tundra
Swans, returning to their nesting grounds in the Arctic. A majority of them spent the winter on the
Atlantic coast in an area roughly reaching from Chesapeake Bay to North
Carolina. Thirty or more years ago Tundra Swans would have been the only swan
species you would see in Wisconsin, but things are different today.
In 2020, there are three species of swans found in
Wisconsin; Trumpeter, Tundra and Mute.
Mute Swans have an orange bill,with a black knob on top, and hold the head and neck in an "s" shape, (Flickr image) |
The Mute Swan is introduced and considered an invasive
species because it is one of the most aggressive waterfowl in the world, driving
everything else from the wetland during its nesting season. They are a large swan with an orange bill that
has a black knobby bump on the top. When Mute Swans swim they hold their necks
in a curved “s” shape. And that is the last I shall speak of them in this
article.
The two native species of Wisconsin swans are the Trumpeter
and the Tundra Swan. The fact that we can find Trumpeter Swans in Wisconsin at
all in 2020 is amazing. Trumpeter Swans, once found over much of North America
were severely over-hunted, and also suffered great habitat losses which took
them to the brink of extinction. By the mid-1930’s there were only 69 known
Trumpeter Swans in the lower 48 states, and they all lived in Yellowstone
National Park and another small area in Montana. Thanks to re-introduction,
education and conservation efforts, the United States Fish and Wildlife Service
reported over 63,000 individuals in 2015. The Wisconsin Department of Natural Resources
survey reported close to 6000 birds in Wisconsin as of July 2019.
Trumpeter Swan (image by Ruth Forsgren) |
First thing to consider is what time of year you are seeing
them. We only see Tundra Swans during their spring and fall migrations. The two
time windows that we can see them is roughly from mid-March through first week
of May and then again from Mid-October through November (keep in mind the birds
cannot read a calendar and can be here outside of those time frames). Since Trumpeter Swans nest and can overwinter
here in Wisconsin they are considered year round residents. So, if you are
seeing a swan here in January or July then it’s a good bet that it is a
Trumpeter.
I think the next easiest way to distinguish between
Trumpeter and Tundra Swans is by learning their calls. Trumpeter as their name
implies has a very trumpet-like quality to their call. The Tundra Swans used to
be known as the Whistling Swan because of their higher pitched whistle-like
call. I don’t think of whistling when I hear them, to me they sound like a far
off crowd cheering (think high school football game from several blocks
away).
There are physical differences between the two species. Trumpeter
Swans are larger, in fact they are the largest waterfowl species in North
America and also our heaviest flier. Trumpeters have a 7 to 8-foot wingspan,
stand 4 feet tall and on average weigh between 20 to 30 pounds (some of the
males, AKA cobs can weigh over 35 pounds).
Tundra Swans on the other hand; have a 6 to 7-foot wingspan, stand 3
feet tall and on average weigh between 13 to 30 pounds.
Tundra Swan (Flickr image) |
Trumpeter Swan (image Ruth Forsgren) |
The Trumpeter Swans usually show a red or dark pink stripe along the lower bill that looks a little like they are wearing lipstick. The Trumpeter Swans eyes are within the black mask of the bill, making it tough to distinguish the eye from the bill. Tundra Swans eyes are a little more separated from the bill making the eye a little more distinct.
Both of these swan species eat aquatic vegetation and
require wetlands with a variety of emergent (sticking out of the water) plants.They also use the wetlands for nesting.
Tundra Swans typically lay from 3 to 5 eggs; the larger Trumpeters can
lay from 5 to 9 eggs. The young of both species are known as cygnets. Cygnets are
grey for their first year. The young will stay with the adults until the next
nesting season has begun.
Trumpeter Swans with cygnets, Crex Meadows Wildlife Refuge (image Ruth Forsgen) |