Home on Manitoba’s range, there are some discouraging words, especially when talk turns to bird habitat and populations. At a recent meeting in Winnipeg that flagged the importance of conservationists supporting the beef sector and their record of preserving habitat, it soon became clear that stemming the decline of forage-based beef production in the province may be the best hope for habitat-challenged species such as the burrowing owl.
For example, there haven’t been any sightings of the iconic burrowing owl on southwestern Manitoba pastures for the past several years.
Likewise the loggerhead shrike is now in steep decline after a couple of population increases in the mid-2000s. At present, there may be 20 to 30 known pairs left in one study area that’s been tracking the population.
Ken de Smet has the longest-range view of these trends in the province. He’s a provincial avian species-at-risk specialist, soon to retire from a career spanning 32 years that encompassed what is possibly the longest prairie grassland bird-monitoring study ever done in Canada.
Why it matters: There are steep and ongoing declines of grassland bird populations. Scientists say monitoring these bird populations over longer study periods is needed to give us the full picture of what’s happening to them.
It can be depressing to have witnessed these trends, said de Smet. There’s a multitude of factors bearing down on these bird populations, with habitat loss being one, as well as spells of wet weather, and changes to land use practices and prairie ecosystem.
Solutions are hard to identify and near impossible to fix, he said, and he likens work with endangered species to trying to fix a leaking pail.
“As you’re plugging one hole another one starts,” he said. “You never totally solve the problem, and it changes over time.”
But that’s not to say the situation is impossible. Take the case of the burrowing owl, for example.
Their numbers, and other threatened grassland birds, could possibly rebound one day — if we don’t pull the habitat rug entirely out from under them, de Smet said.
There’s a lot to be learned taking the bird’s-eye view from a study that goes on as long as de Smet’s has. Long-term studies yield more robust and accurate data. Short-term views can be misleading.
“The longer you look at things, the more you figure out, and the more you see the cycle of events,” he said.
An employee of the Wildlife and Fisheries Branch of Manitoba Sustainable Development, de Smet is well known among Manitoba farmers, especially those in the Melita region.
In a recent talk given at the Prairie Conservation and Endangered Species Conference in Winnipeg, de Smet spoke of various ‘trials and tribulations’ spent monitoring the status of the burrowing owl, as well as loggerhead shrike and ferruginous hawk, over all these years.
He has also done extensive work to track Sprague’s pipit, chestnut-collared longspur and Baird’s sparrow.
His watch for burrowing owl began in the late 1980s, when there was reasonable population in southwestern Manitoba, due to reintroductions that had begun in 1987. They were using borrowed birds from then more plentiful populations across the border in Saskatchewan. But few birds returned past a couple of seasons and reintroductions didn’t continue beyond 1996. There was very little sign of them after that.
Then, suddenly, there was burrowing owl again between 2006 and 2010, after which the wet spells drowned out nests, taking a toll on the population.
“We haven’t had a for-sure wild nesting pair now for I think three years,” said de Smet.
“That’s not to say there isn’t the odd one out there, but there aren’t many.”
Therein lies the value of doing long-term studies, he adds. Had their efforts wrapped up at a different juncture, they’d have drawn different conclusions.
“At one point, we’d have said, ‘we don’t have to worry about them,’” he said.
Ferruginous hawk and loggerhead shrike populations tell a similar tale. In the early 1990s there were over 50 pairs of the former, with a slight drop in numbers by the latter part of the decade, then a rebound in the mid-2000s. In recent years just 10 to 12 pairs of the large bird of prey have been found.
Likewise, the loggerhead shrike is now in steep decline after a couple of population increases in the mid-2000s. At present, there may be 20 to 30 known pairs left in the study area, although less monitoring of this species has been done recently.
Signs of hope
Time isn’t what at-risk grassland birds have, given their precarious hold on habitat. But de Smet isn’t giving up hope for them either.
Other bird species have proved tenacious, and he points to the astonishing recovery trumpeter swan is making in Manitoba, after once dwindling down to zero here, plus the return of bald eagle to southern agro-Manitoba where treed habitat is available to nest in. Likewise peregrine falcon is adapting to urban environment, and raptors such as hawks and some species of owls are also generally doing well, said de Smet.
Meanwhile, small populations of chestnut-collared longspur remain in areas like the recently designated Important Bird Area (IBA) of the Ellice-Archie Spy Hill community pasture.
That’s the direction that’s needed, said de Smet.
“That site is large enough that it supports a pretty substantial population,” he said.
“As long as we stay focused on preserving, and where possible, enhancing quality and quantity of habitat for species recovery, all hope is not lost.
“And that’s as encouraging as I can put it.”