Naturalist's Corner - Tons of Tundra Swans

Today we dig a little more deeply into the fall migration of tundra swans, a wonder along the Mississippi River!

Just as the trees have dropped their colorful autumn leaves and the dominant color in woods and fields are greys and browns, the tundra swan migration goes into high gear along the Mississippi River flyway near where we live in southeastern MN. Those brilliant white birds are like another party getting started!

This annual tundra swan fall migration hits our area just about the beginning of November and lasts until the end of the month. Shallow pools along the river sloughs are filled with their raucous calls. We see tens of thousands stopping on their migration routes. 

The most numerous species in North America, tundra swans (also called whistling swans) are slightly smaller than mute or trumpeter swans. They are white with a black bill which often has a spot of yellow on it near their eye.

Image courtesy of US Fish and Wildlife Service

They are dabblers - they upend themselves to eat their favored tubers - up to 6 lbs of "duck potatoes" a day.

I had always thought that the migrations from their summer nesting grounds to their winter grounds in the Chesapeake Bay area in the eastern United States and back again in spring were quick runs. I was surprised that studies tracking swans suggest that the swans spend over 4 month each year in their migration! 

The fall migration from the Arctic circle to Chesapeake Bay area is a journey of over 3000 miles. According to a study tracking a small sample of tundra swans written by Khristi A. Wilkins et al published in Wildfowl (2010) 60: 20–37, each of the 3 or 4 stops the swans make along the way lasts for 2-3 weeks as they rest and refuel before the next stop. The swans don't leave together and all at once, but rather there are staggered flights beginning from early September through early October. 

The green line shows the tundra swan migration path on the map

The swans can often stay in the Upper Mississippi river for a few weeks at a time before heading, in their final lap, to their Chesapeake Bay area wintering grounds. They take a sharp easternly turn and head directly there, with the final swans arriving from November through December. That's why habitats with a good food supply and vast areas where the migrating waterfowl can rest is so critical.

It speaks to the importance of all their resting stops. Healthy natural areas can support the migrations - especially in times of climate change. I will be watching in coming years to see what kind of impacts the warming temperatures might have on this important migration.

Meanwhile, now is the time to join the tundra swans' raucous migration party. The US Fish and Wildlife Service is sponsoring a number of staffed weekend viewings in the next few weeks to help you learn about and identify the swans and other waterfowl and birds migrating through.  Read on:

Swan Migration at Brownsville Overlook    

Saturdays/Sundays  Nov 11/12 and Nov 18/19   10am-2pm

Come enjoy the fall migration! As the seasons turn colder, thousands of swans, ducks and other water birds move through the refuge, finding a place to rest, relax and refuel before moving further south for the winter. A Refuge naturalist will be stationed at the Brownsville Overlook to help visitors identify birds and share information about the refuge and migration. Please note that naturalists’ shifts may be cancelled or end early without warning in inclement or extremely cold weather. The Brownsville Overlook is located about three miles south of Brownsville, Minnesota along Minnesota Highway 26. A portable restroom will be available on-site. We recommend wearing lots of warm layers!  Though peak migration is difficult to predict, the best time to see the tundra swan migration is usually the second or third week in November. The swans will typically stay until the water freezes over – if temperatures stay below freezing at night, the peak of migration will be earlier in November. Warmer weather extends their stay. Recent sightings and estimates of bird numbers are posted weekly on the refuge website.  For more information, please call the La Crosse District Visitor Center at 608-779-2399 (Tues-Fri 9am-3pm) 

The Friends of the Upper Mississippi will join the refuge on Saturday Nov 11 for Waterfowl Observation Day: Come join the Friends of the Upper Mississippi (FUM), Friends of the Refuge –Mississippi River Pools 7 & 8 (FOR78) and the Upper Mississippi River National Wildlife & Fish Refuge to celebrate the fall migration! Spotting scopes and bird identification guides will be available for visitors to enjoy. Refuge staff, and members of FUM and FOR78 will assist with bird ID and related questions. Please dress for chilly weather! Light refreshments will be available while supplies last, during this event only. All donations for refreshments will benefit FUM. Members of FUM and FOR78 will have wildlife-themed items available for purchase. The Brownsville Overlook is one of the best places along the river to view hundreds of tundra swans, ducks, pelicans and bald eagles. The overlook is located about three miles south of Brownsville, MN along MN Highway 26.

You can read more about the tundra swans spring migration and habits in this recent post by Charlotte Lukes.

A huge thank you to Katie Julian of the US Fish and Wildlife Service who shared the research that helped me write this post!