Birds flocking to national parks in the Canadian Rockies
'Our populations are stable to increasing,' Banff wildlife ecologist says
It turns out tourists aren't the only ones who love the national parks in the Canadian Rockies.
Despite recent studies showing bird populations are declining in many areas of North America, scientists with Parks Canada have found that most songbirds are doing well in Banff, Jasper, Waterton Lakes, Yoho and Kootenay national parks.
"Our populations are stable to increasing," Jesse Whittington, a wildlife ecologist with Banff National Park in Alberta, said in an interview.
Whittington was a lead author on a paper published in November in the journal Ecosphere that looked at broad trends in bird populations in the five mountain parks in Alberta and British Columbia.
"Our study had three main objectives: We wanted to know how our bird populations are changing over time and how has climate change affected our bird populations, then how can we make our bird monitoring more efficient."
Whittington said scientists have been monitoring bird populations in the five mountain parks since 2007. Equipped with audio recorders, they hike into specific sites every spring when birds are most vocal.
"We analyzed bird trends for 64 species from 544 sites," he said. "We detected over 34,000 bird songs.
"Over that time, we found that 91 per cent of the bird species increased their range over 10 years. That was really good to see."
'Climatic niche'
Two other recent studies have found numbers for most bird species are dramatically dropping. One report concluded overall numbers have declined by three billion since 1970 — about a 30 per cent drop.
Whittington said their study looked at whether specific birds — such as dark-eyed juncos, white-crowned sparrows and yellow-rumped warblers — were present or absent at each site.
"It's pretty hard to estimate the actual number of birds we have in Banff National Park, so we looked at whether their range was increasing or decreasing over time," he said. "Range contraction and expansion is correlated with increases and decreases in population size."
Whittington said the study also looked at what role climate plays in the trends.
"All birds have what's called a climatic niche, so they have this temperature range that they do best (in)."
The Parks Canada scientists discovered that most birds expanded their range during warmer and drier springs.
Whittington said some might think that means climate change is good for bird populations, but he suggested it's likely related to the location.
"Certainly in the mountain parks, it's a pretty rugged environment. It's cold and relatively inhospitable."
Whittington said it would be interesting to compare their results to other locations outside the protected areas. To that end, they are making their research available to other scientists.
Their study, he added, showed migrant birds also responded to changes in temperature and precipitation more than the winter residents.
On the technical side, Whittington said the study built upon work of other researchers, who monitor sites multiple times throughout the year.
"What we did was actually estimate the bird's singing rate," he said. "In using that, we could estimate probability of detection with just one site visit."
The study's findings support a growing body of research that suggests bird populations are more resilient in protected areas.