Impressive carnivores like grizzly bears, wolves and cougars get a lot of attention, but the smaller critters of Banff National Park also have an important role to play in ecosystem health.
From songbirds and pikas to amphibians, Parks Canada is keeping close tabs on wildlife population trends in the national park using a broad network of remote cameras, recording devices and good old-fashioned fieldwork.
“Every year I roll up the data and estimate occupancy – presence and absence throughout a species’ range – and look at what our trends are to these species,” said Jesse Whittington, a wildlife ecologist for Banff National Park during a recent presentation to Bow Valley Naturalists.
A lot of attention is being paid to pikas, a sensitive species that can act as an early warning system for much more widespread impacts from a warming climate such as shrinking of high country habitat.
Living in colonies often connected by a maze of tunnels underneath rocky area, pikas spend their summers collecting grass and other vegetation to build into hay piles.
They don’t hibernate in winter, but instead use their hay piles to survive and eat during the snowy, winter months.
Whittington said researchers have been looking at population trends and growth rates across a range of elevations and snow conditions by keeping track of the number of hay piles since 2011.
While pikas are in trouble in the southern extent of their range, he said the population in Banff National Park seems to be stable to increasing.
“We were even curious how the heat dome in 2021 was going to affect this population; it was smoking hot, but they did just fine,” he said.
“Maybe they can hide in the rocks and come out at different times of day when it’s cooler, is my guess, and they were able to go deep in subterranean chambers during the hottest times of the day.”
While counting hay piles is a basic method to look at pika numbers, it has its limitations, and researchers wanted to see if they could narrow down population trends even further.
In 2022-23, Parks Canada piloted a novel approach based on visual surveys of pikas, hiking a transect and stopping frequently to see if they could spot or hear pikas.
Well camouflaged and living on rock slides and talus slopes in high alpine regions, pikas can often be located by their piercing call that sounds like a high-pitched “eep”.
When no pikas were detected, surveyors played a recorded pika call on an external speaker – a call back – every 50 metres to improve detection.
Whittington said some pikas investigated call backs by climbing on top of the talus.
“If you play this, the pikas will pop out and it actually increases our detection rates quite a lot,” he said.
Whittington said preliminary results indicate this method is likely a good alternative for long-term trend modelling of pika abundance.
“We’re doing some preliminary analysis and right now this technique looks promising,” he said.
“It will be important for us to understand things like how climate change affect pikas and affect the alpine ecosystem, but overall pikas seem to be doing pretty well for now.”
Songbirds
Parks Canada is also monitoring songbirds in Banff National Park, where there have been more than 260 species recorded – from the trumpeter swan, the largest bird spotted in Banff, to the smallest calliope hummingbird.
Researchers hike for hours to remote locations to capture recordings of their songs, which reveal patterns about which birds live in the park and where they are, providing clues about the health of the park’s forests and alpine.
Researchers say it’s important to get there early so they can hit the record button when birds are most actively singing, noting these recordings are reviewed by an acoustic specialist to identify birds by their songs.
Some species did decline, including gray jays, olive-sided flycatchers, hairy woodpeckers, pine siskins, and savannah sparrows, but Whittington said research over the past decade showed most bird species were stable to increasing.
“Songbird populations are declining throughout a lot of North America and the world, but they’re actually doing pretty well in the mountains,” said Whittington.
“Most of them – not all of them – do better in the hotter, drier summers here, just because they’re on the edge of their range, but we will continue to monitor over time and see how a changing climate affects these guys.”
In addition, researchers are looking at potential changes in songbird populations with the reintroduction of plains bison to remote areas on the eastern slopes of Banff National Park.
Birds line their nests with bison hair and create shallow depressions known as wallows as they roll in the dirt, which can fill with water and provide valuable habitat.
“One of the neat things about that is we’re finding several grassland species up in this bison range – Ya Ha Tinda, Panther Valley – that we don’t find in the main Bow Valley,” said Whittington.
“It will be interesting to see if – as the bison population increases, as they graze some of these meadows more intensively – it might change diversity or abundance of songbirds.”
Like grizzly bears, bison are considered umbrella species, which essentially safeguard the quality of life of other species in the food chain and maintain the natural balance of the environment for species like birds.
Colleen Campbell, a member of the board of directors of Bow Valley Naturalists, said the smaller critters play a vital role in ecological health.
“We give short shrift to describing how everything is connected. John Muir said it best, ‘when we try to pick at anything by itself, we find it hitched to everything in the universe,’” she said.
“The whole notion of umbrella species is discussed by hardly ever parsed.”
For example, Campbell said what happens when grizzly bears eat hedysarum, digging out the roots in fall and deftly clawing out the interior threads of the protein plant.
“The bears dig and loosen the soil over broad areas while digging the hedysarum, releasing nitrogen – an excellent natural fertilizer – into the soil,” she said.
“The nitrogen benefits all the plants that grow, bringing benefit to the birds and the pollinators and all the other species that find scour in the alpine meadow.”
