From the Contact Station November 2020

Swans, Cranes and Other Surprises

One of the most frequent Fall questions at the contact station, if not the whole year is, “Are the swans here yet?” There seems to be a special excitement about seeing these wonderful, lovely, elegant birds. Arrival time is around the last week of October with maybe a few sneaking in before that. They usually show up at Carty Lake first. You can see them at the overlook from the port (the trail is closed this time of year) or take a walk over the entry bridge into the Carty Unit and view the north end of Carty Lake from the top of the bridge (best to check on access on the Refuge2020.info website due to the construction near the Carty Unit entrance). Eventually they will find their way to Rest Lake on River ‘S’ or the lake just beyond the hunt gate to the right, which you can see as you turn to left on the auto tour. It depends in part on how quickly the River ‘S’ lakes fill with water and knock down the vegetation that has grown up during the summer. In winter, birds select sites with low water velocities, higher food density, and are expansive enough to be able to distance from vegetation. They like lakes about a meter deep where they can tip up their rear end and extend their necks to reach food. A Trumpeter needs about 100 meters of runway to get that massive body back into the air.  It makes sense that they chose Carty Lake first and Rest Lake later in winter.

We have two swans that visit the refuge in winter: Trumpeter Swan and the Tundra Swan. The Trumpeter Swan is the largest native North American waterfowl and outweighs all

other North American species coming in at 22 to 30 pounds. It can measure as much as 6 feet long. It is long-lived and a social species usually mating for life. It is primarily herbivorous, feeding on submerged and emergent vegetation. Best recognized on the refuge by its trumpet-like call, its numbers are small here compared to the Tundra Swan. The Trumpeter, at one time abundant and geographically widespread, was severely impacted by European settlement of North America (1600s–1800s) as it was prized for its skins and primary feathers. By 1934, only 69 individuals were known to exist in the contiguous United States, though unrecorded flocks were in Alaska and Canada. With conservation, including protection from shooting, habitat management, and range expansion programs, the Trumpeter Swan is recovering. The 2015 continental estimate of white swan abundance was 63,016, an 80% increase over 5 years earlier.

Tundra Swans are a bit smaller than Trumpeters, coming in around 12 to 16 pounds on average, but much more abundant on our refuge. Breeding on high arctic wetlands, they winter along east and west coasts. Also, a long-lived species, this swan forms monogamous pairs. The wintering young remain with their parents until their arrival back on the breeding grounds the following year. The Tundra Swan’s diet consisted primarily of submerged

aquatic vegetation and benthic organisms (any critters they might find buried in a pond or estuary mud). But their feeding habits have increasingly turned to open agriculture grain fields in winter, which can be problematic in some areas. Like the Trumpeter, they feed by extending their necks to the bottom of lakes and ponds. If you see them coming in for a landing on a lake, listen for their characteristic whistling sound as the wind moves through their feathers. Hence their original name, Whistling Swan.

Distinguishing Trumpeters from Tundras is not easy, but here are a few hints:

• Listen to their calls. The Trumpeter trumpets! Usually a two-note call, described as Ko-hoh, but can sound like multiple toots if several of them are calling at once. The Tundra Swan has a more mellow call as in hoo-ho-hoo. A good way to hear these calls before you visit the refuge is via Cornell’s All About Birds website.
• Trumpeter Swans almost always have solid black bills, with the black markings extending to the eyes. On a Tundra Swan you can usually see a yellow patch below the eyes. The patches vary in size and may be hard to see so absence of yellow doesn’t necessarily mean Trumpeter. You must look at all the characteristics.
• Tundra Swan bills typically have a concave, or scooped shape. On the Trumpeter, the bill is typically straight, and there is often a red “lipstick” marking where the upper and lower bills meet. Be mindful of your angle of view; it can sometimes trick your mind.

-Susan Settergerg, Contact Station Volunteer