About elaine

Elaine monitors the local Trumpeter Swan population for the Blackfoot Challenge and US Fish and Wildlife Service. She also participates in science education programs in the Blackfoot Watershed.

Ups and Downs

This past spring saw quite a few days of cool, wet weather in the Blackfoot, which seemed to affect our swan productivity this year. There were six known nesting attempts, five of which were successful, producing a total of twelve cygnets. This is a bit fewer than in the past couple of years, when we had 24 cygnets (2016) and then 20 cygnets (2017) hatch.  One nest that has been successful the past two years was actually underwater for most of the nesting season, and the pair did not nest at all.

Since Trumpeter Swans must incubate their eggs for around 34 days in May and June, it can be tough to make sure those eggs stay at the right temperature the entire time, since the female swans must get off the nest occasionally to feed. While the males of some bird species will share incubation duties with the females, in most waterfowl the incubation is solely the job of the females. As long as it is not too hot or too cold, they can leave the nest at times by covering their eggs with nesting material and downy feathers.  This insulates the eggs from the weather and also hides them from potential predators.  It’s likely that in a cool, wet spring there will be times when that strategy fails to keep the eggs warm enough.  In our watershed one nest failed entirely this year, one had only one cygnet, and two had only two each, although the other nests had three and four each.

However, the great news is that all twelve of those cygnets have survived so far!  It’s pretty unusual for all that hatch to survive the first few months, and as they get larger they are vulnerable to fewer predators, so the outlook for a healthy number to make it to fledging (flying) age is good.

You may recall that last year we had to cancel the swan release due to wildfire activity and smoke.  We were able to release those swans as yearlings this past spring, and planned another public release this September with young swans hatched in captivity in May.  However, like our Blackfoot nests, the swans at the facility where they are hatched did not do very well this spring either.  Unfortunately, that means they don’t have any young swans for the Blackfoot and we will not have a swan release this fall either.

While it is very disappointing that we won’t have this wonderful fall event for the schools and the public again this year, the good news is that our swans seem to be slowly but surely increasing their numbers on their own.   Our monitoring efforts from the ground and a recent survey flight showed 45 adult Trumpeter Swans in the valley along with the 12 cygnets. Most of those “adult” swans are likely one or two years old and have not yet begun to look for a mate and territory.  Hopefully they will continue to return to the Blackfoot in the spring and soon be ready to settle down and raise families of their own.

Snow Geese Scouts

Many Blackfoot residents have noticed the unusually high numbers of Snow Geese (along with swans and ducks) in the watershed this year, and that they have been staying around longer than in other years.  We’ve thought it likely that they were piling up here where there has been at least a little open water and fields, waiting for things to thaw to the north.  Now we are seeing big flocks leaving the watershed, heading north over the Bob Marshall.   And a biologist in California has some really cool transmitter data showing not only that a lot of the geese that winter in California have been passing through here, but that some of them seem to scout out conditions in the north while they wait!  Chris Nicolai of the U.S. Fish and Wildlife Service put radio transmitters on 39 geese in the Central Valley and has been following them via satellites as they’ve migrated north.

Radio telemetry locations of Snow Geese migrating out of California’s Central Valley in spring 2018

The map above shows that most of them have come through Montana and spent weeks in the Great Falls area before moving to Canada recently.  And at least one goose made two trips up to Alberta and back to Benton Lakes in Montana this spring!  We don’t know if these birds have some way of communicating with the rest that conditions are not right to continue migration or if these are just overeager individuals that can’t help checking things out.  But it does seem that most of the flocks have some way of knowing when to move.  And the warmer, drier weather that has accelerated our snowmelt and started to open up the lakes has put them back on course.  The map below shows that some of these geese came right through the Blackfoot on their way north:

Locations of Snow Geese in Montana this spring as they migrated north to Canada.

 

You can track these Snow Geese directly by going to https://www.movebank.org/node/36241 and searching for Wintering California Geese.  Or you may be able to see a big flock overhead if you are out and about in the Blackfoot today!

Swans in the Blackfoot: Trumpeters or Tundras?

Tundra Swans flying over Wigeon Marsh near Ovando on April 1.

This time of year, as well as in the fall, I have to take a close look at–or listen to–any swans I see, to know which species I’m observing. While we are now fortunate enough to have a fairly robust summer population of Trumpeter Swans in the middle and upper Blackfoot, we also have migrating Tundra Swans that pass through on their way to nesting grounds in the Alaskan and Canadian Arctic.  These “cousins” to our Trumpeter Swans can be difficult to tell from trumpeters, even by expert observers!

The Sibley Guide website has a lot of good information on distinguishing the two, as does the Trumpeter Swan Society . Trumpeters are larger than Tundra Swans, although it’s difficult to see that unless they are side by side.  Trumpeters have long, straight bills, usually with a strip of orange on the lower part.  Tundra Swans have rounder heads with shorter, more concave bills.  Tundras typically have yellow spots on the black “lores” near their eyes, but they can also have orange strips!  As you can see from the photo below, they can be difficult to identify unless you can clearly see them side by side.

Adult Trumpeter Swan (left) and adult Tundra Swan (right) showing larger size difference of Trumpeter and different bill shape. Toronto on 17 December 2017. Photo by Jean Iron, used with permission.

The sounds the two species make are very distinct, however, and this is the easiest way to tell them apart if you are lucky enough to hear them. Tundra Swans were formerly called Whistling Swans, and they definitely have a different call than the low tone of the trumpeters.  You can hear the sounds of Trumpeter Swans here and compare them to the higher pitched “whistle” of the Tundra Swans here.

Mute Swans, an exotic species from Europe, have become established in some parts of the eastern U.S. and Midwest, but fortunately have not made it to Montana, as they are aggressive competitors with our native swan species and can damage ecosystem functions.  I had a scare last week as we were driving home from Oregon and saw a golf course near Spokane with Mute Swans in several of the ponds!  On closer inspection they turned out to be decoys, probably placed there to scare off geese and ducks, but they also gave a fright to this swan observer.

With many bodies of water still frozen in western Montana, people are seeing lots of swans and Snow Geese filling up the few open ponds and fields.  It’s a wonderful time to be out and about, hearing the cries of the wild flocks as they wing their way north or settle down for some important rest and refueling on their long journeys.  The wetlands of our watershed provide vital habitat for so many species throughout the year.  And it’s just as exciting to know that some of the swans will stay right here in the Blackfoot to raise their young this coming summer!

Summer Swan Roundup

Where’s the best place to be in a hot, smoky summer of fires?  A wetland, of course! While the rest of us were sweating and fretting, our swans seem to have fared just fine in spite of some major fires that burned in the surrounding mountains. Nineteen of the twenty cygnets that hatched in May and June have survived and are now in the process of learning to fly.  

When the cygnets hatched in the spring, they weighed about 7 ounces. In an astonishing feat of growth, they gained up to 20% of their body weight every day for a few weeks, at some point increasing by a pound a week, until reaching about 20 pounds at this time of year. Their early diet was composed mostly of protein-rich insects and other aquatic invertebrates, which enabled this rapid growth.  Not only were they gaining weight and getting larger, they were also growing all the body and flight feathers they will need to carry them to their wintering grounds in a few short weeks.

Trumpeter Swan family loafing on the shore. If you look very carefully you may be able to see the black bill and white head of the other adult peering out of the grass toward the left side of the photo.

The cygnets will soon take to the air in short flights across the wetlands, and make longer flights in the area with their parents as their flight muscles grow stronger.  Sometime before freeze-up they will leave the watershed in family groups, heading for wintering areas to the south, where waterways remain open and aquatic vegetation is accessible. There they will mix with Tundra Swans from the north and other Trumpeter Swans from the Canadian and American Rocky Mountain region.  In the spring the family will migrate north again to the Blackfoot, and the adults will chase their offspring off their territory in anticipation of producing a new batch of young.  The yearlings will likely stay together and perhaps join other young swans for the summer.  At two years of age they will begin to seek their own mates and territories.

We had to cancel our fall Swan Release event due to wildfire proximity and smoke.  The captive cygnets we planned to release will be held in captivity over the winter and released in the Blackfoot next year under better conditions.

A New Generation of Swans

It seems that every year is a little different for Trumpeter Swans in the Blackfoot, and this year is no exception! At least 36 swans returned to the watershed this spring, including a record number of 13 pairs. There are also two groups of yearlings from last year’s nests around, and one yearling that was released last year.

It appears that a couple of our pairs lost one member from last year. One of these surviving swans returned with a new mate and another seems to have returned with its yearling cygnets but no mate. For this and perhaps other reasons as well, we only had five active nests this year, down from eight last year. However, those five nests were all successful and have produced 20 or more cygnets in all!

Additionally, one of those nests is new this year, and it is near Lincoln, so our population appears to be slowly spreading throughout the watershed. This is also closer to the site on the Bouma Post Yard where Trumpeter Swans attempted to nest in the Blackfoot in 2003, after being absent from the watershed for over a century. And we have swans on several lakes in the Clearwater branch of the watershed as well, all of which bode well for the continued success of Trumpeter Swans in the Blackfoot and beyond.