Skip to content

Researchers use innovative techniques to study endangered black swifts

“These guys are in danger, but they are really, really cryptic and hard to study,” said Barb Johnston, the species at risk biologist overseeing the black swift project in Banff National Park.
The black swift is an endangered species in Canada.

BANFF – Desperate times call for desperate measures.

With little known about the rare black swift, Parks Canada researchers are testing innovative ways to help protect this endangered species, including scouring through poop to find out exactly what these birds are eating.

“These guys are in danger, but they are really, really cryptic and hard to study,” said Barb Johnston, the species at risk biologist overseeing the black swift project in Banff National Park.

“We’re kind of stepping outside the box and using some unusual techniques to try and shed light on the basic biology of the species because there’s not a whole lot known about them.”

A critical nesting area for the endangered black swift is found along the cliffs of Johnston Canyon, one of the most visited tourist hotspots in Banff National Park, drawing hundreds of thousands of visitors a year.

Researchers are using thermal imaging cameras to locate and monitor nests, time-lapse remote cameras to reveal bird activity patterns and temperature and humidity sensors to help understand this species’ micro-climate needs.

This summer, researchers will use DNA meta-barcoding of fecal remains of birds to learn about their diet.

“It’s a diet analysis. We’re trying to find out what these guys are eating,” said Johnston.

“It’s a really unique opportunity to do some of this research because most sites where they nest are so inaccessible, but Johnston Canyon is actually accessible.”

Five active black swift nests were confirmed in Johnston Canyon in 2021 – the highest number of active nests recorded in Johnston Canyon since 2004.

In 2020, three nesting pairs were spotted in the canyon, while only one or two active nests were recorded between 2005 and 2019.

While the increase in nesting pairs is a positive sign for the black swift population, it is still below historical numbers of up to 12 active nests in the 1970s and early 1980s.

The black swift nesting colony in Johnston Canyon was initially discovered in 1919 and was the first confirmed inland nesting site in North America.

The bird is recognized by its black plumage, long and pointed wings and unique notched tail.

“Although we know the population has declined really dramatically in the last few decades by half, there’s no consensus on what the cause of that decline is,” said Johnston.

While causes of the decline are not fully understood, scientists suspect it is in part related to changes in food supply that may be occurring at one or more points in the black swift’s life cycle.

Black swifts, like with many other birds, specialize on a diet of flying insects, and airborne pollutants have been killing off insects.

“Airborne pollutants are just generally reducing the amount of aerial insect food out there,” said Johnston, noting many other species that rely on insects are also not faring well.

“This is in general, across the board, creatures that are dependent on insects, and insect numbers are going down because of chemicals that we’re using,” she added.

“If they rely on this as food and the amount of it’s going down, then it’s probably affecting the population.”

Black swifts also may be sensitive to climate change, probably because waterfall nesting sites are likely to be impacted by decreased snowpack and glacial melt.

However, Johnston said climate change can also lead to what is called a temporal mismatch between the timing of things in a species’ life cycle.

“For these guys, it would be a mismatch in the timing when these bugs are available and when they most need them in their life cycle,” she said.

“That’s around when they’re laying an egg and they’re really energy needy, or when they’re provisioning the chicks,” she added.

“If there’s going to be a mismatch from when there’s a lot of food and when they need that food, again there’s going to be a population decline and we’ve seen that in other species.”

The Canadian Wildlife Service research scientists did a study on the diet of black swifts approximately 40 years ago.

Banff researchers thought they could follow up on that now by collecting bird poop, which is the only real way of finding out what black swifts here are eating specifically.

“If we can find out what they are eating now, it will be interesting to compare that to what they were eating before the decline in population and we can see if there is a difference,” said Johnston.

Researchers will look at the bird poop microscopically, and look for exoskeletons.

“We can look at those exoskeletons in their feces and see what type of bugs they’re eating,” said Johnston.

“Are they ants versus beetles? We can see what’s the size, how many and what general kind of bugs are they eating.”

New technology means researchers can also use DNA meta-barcoding, which basically means DNA is extracted from poop.

“In that soup of DNA, there’s little segments of different species…” said Johnston, noting it can be compared to hundreds of thousands of species in a DNA database.

“In one sweep we can see all the different species that they’re eating. It doesn’t tell us how much and it doesn’t tell us what size class, but it will tell us what species they’re eating.”

Parks Canada has experimented with other innovative techniques to monitor the black swifts of Johnston Canyon.

Researchers have already had success locating nesting birds with non-intrusive thermal imaging cameras – which are also used to detect wildfires or make sure prescribed burns are out.

Johnston said black swifts are hard to detect because they nest in cold, dark places.

“We thought if these guys are warmer than their ambient surroundings, it should pop out in these cameras and we discovered that is the case,” she said.

“When you look at a cold cliff wall, you can see the outline of a bird or a nestling sitting there, so that’s now the main way we are able to say if a nesting area is active.”

Time-lapse cameras, which are also considered non-intrusive, are also used to keep an eye on the birds.

Researchers have set the cameras to take pictures every hour.

“We can find out when the adults are coming and going, when do they arrive back in the spring, when do they lay an egg, when does the baby leave in the fall,” said Johnston.

“It also tells us how often the adults are coming and going to provision the young guys with food and how that may change over the season.”

The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) designated the black swift as endangered in 2015 and the species became federally protected under the Species At Risk Act in 2019 as populations plummeted by more than 50 per cent over the past 40 years.

Although little is known about the biology of the black swift, it’s believed the species mates for life and lives upwards of 16 years of age.

Black swifts also only lay one egg a season and have a lengthy seven-week rearing period, with chicks not fledging until near the end of September.

The nesting duties are shared by the parents, with both the male and female trading off shifts during the incubation period.

It wasn’t until 2012 that it was first discovered that black swifts fly to South America to winter.

Several birds from Colorado were tagged with tracking devices, which indicated their wintering grounds were in the Amazon rainforest of Brazil. There was also a reported sighting of a black swift in Tambopata, Peru, in 2012.

However, COSEWIC indicates there is no information on whether black swifts that breed in Canada winter in the same region. Canada is home to about 80 per cent of the North American population. “Indeed, the wintering area of birds from different breeding areas in North America remains to be determined,” according to the group’s status report on black swifts.

Johnston said the birds, which have fidelity to their nesting sites, are expected to return to Johnston Canyon in May.

“They are down in the Amazon, and they will fly back in spring, and that’s a really critical time for them,” said Johnston, noting the nesting period is one of the most sensitive times for birds.

“They are looking for suitable nest sites and they are looking for places where they’re not going to be disturbed and where it’s safe from predators.”

Johnston said Parks Canada is excited to see what happens this spring given last year was the highest number of active nests and successful fledglings since 2004.

“That’s a long time,” she said. “We’re hopeful that maybe that path that they’ve started on with this trend of an increase that that will continue and maybe we will see more individuals come back this spring.”

To make sure the endangered black swifts have space and security to nest and raise young, Parks Canada will implement the annual formal closure of off-trail use at Johnston Canyon from May 1-Nov. 15.

Officials say visitors can help with conservation efforts of the black swift by staying on the dedicated trail and obeying the closure.

“This is a rare bird and we have literally a handful of known nests in the province, in fact in the country,” said Johnston.

“Despite the fact it’s a place we all really like to go, it’s important to know this is a pretty unique place and if we disturb the nests, it’s not like we have somewhere else nearby they can go to.”

The recovery strategy for the black swift is still being finalized, with Environment and Climate Change Canada taking the lead.

The document will outline threats to the species as well as actions that need to be taken to save the black swift.

“It will also define the critical habitat for these guys and Johnston Canyon would be one of those critical habitats,” said Johnston.

The only other known black swift nesting site in Banff National Park was discovered in 2020 in the backcountry in the Egypt Lake region.

Confirming nest sites can be challenging, particularly as adult birds often visit nest sites only late in the evening. There are thought to be fewer nesting pairs last year in that location, with a maximum count of five in the 2020 year and two in 2021, though that is inconclusive.

“These guys are so secretive and so fascinating,” said Johnston.