….and other migratory birds at Ennis Lake
If you see Tundra pickup cruise slowly along Ennis Lake, then pull to a stop before a long-lensed spotting scope emerges from the driver’s window, like a periscope, you may have encountered bird expert Gary Swant or his partner and grandson, Caleb Lashway, counting migrating birds as they take a break, or “stage,” on their journey south.
Just as it has been through the ages, many bird species fly north during the spring, then turn around and return south in the fall, clocking thousands of miles. Some birds summer as far north as the Canadian Arctic Circle, then migrate back to the Gulf of Mexico or the California coast for the winter. It’s the waterfowl and shorebirds that Swant follows, and those species like to make Ennis Lake a rest stop.
A retired biology teacher, Swant now surveys waterfowl and shorebirds through his consulting firm, GoBird Montana, and also offers guided bird tours. His interest in Ennis Lake’s visitors stems from a sad event that occurred in 2016, when a number of snow geese dropped into the Berkeley Pit in Butte and died from exposure to its toxic water. The pit was formed during the mining heyday in Butte. Its excavation released naturally occurring arsenic from the hard rock. Since then, former and current owners of the pit (Atlantic Richfield and Montana Resources) have stepped up efforts to deter birds from landing in the pit, and to learn more about migratory pathways and behaviors in order to be best prepared. The 2016 event was somewhat of an anomaly, as the snow geese were late in their southward migration, and many of the ponds along the way had already frozen.
For the second year in a row, Swant and others are monitoring the numbers of waterfowl and shorebirds at lakes in Ennis and Helena and comparing them to numbers of birds seen at the Berkeley Pit.
“The purpose of monitoring Ennis Lake and Lake Helena north of Helena is to determine if birds flying down the east side of Continental Divide can give us a prediction of what might happen in the pit,” Swant explained. “In the spring, if we have high numbers of birds at Ennis Lake and don’t have them at the pit, then we know birds are moving up the east side of the Continental Divide without coming to the pit. Now in the fall, if we have high numbers at Ennis Lake and low numbers on the western side of the divide it means birds are bypassing the pit.”
He explains that on August 16, 278 eared grebes were counted on the lake. But on August 20, more than 600 eared grebes were at Berkeley Pit, and were hazed off. “That says that right now more grebes are going down the west side than the east side of the Divide. We’re trying to decide whether we can use Ennis Lake as a predictor of what may happen in the pit. Then we can be prepared for what’s coming as the birds head south. Based on one survey, it looks like more birds are moving down the west side of the divide than the east. We would rather have them move down the east side, avoiding the pit. But with this information we’ll be prepared.”
Swant also surveys birds from Garrison to Butte, for the same predictive purposes.
The fall migration started officially on August 15. Between now and when the open waters ice over, Swant and his grandson, Caleb Lashway, will be watching birds, counting birds, and hoping to learn what the data mean. The plan is to conduct fall and spring surveys over a five-year period.
Swant and Lashway are interested in 54 species of waterfowl and shorebirds, including American Avocet, Snow Geese, Canadian Geese, Mallards, American Coots, Grebes and Gulls – species that have landed in the pit in the past.
“Migrating birds look for open waters, such as Freezeout Lake at Choteau, Warm Springs Ponds outside Anaconda, Clark Canyon south of Dillon and the lakes at Ennis and Helena, where they can rest and find food,” Swant said. “As long as these waters aren’t frozen, we don’t see a lot of them at the pit. From here, their next stop would be the Salt Lake flats, with ponds found all the way down.”
The data gained about migratory patterns, combined with deterrence technologies, should give waterfowl and shorebirds a little help on their long and arduous journey from the far north to the semi-tropics.
Between now and November when its water freezes, Ennis Lake is a great place to view a variety of birds.