In Bog We Rust: How to catch blackbirds on a birdathon

For this year’s Great Canadian Birdathon we were, somewhat by design, in the field. Much like last year around the same time Jay Wright and I were on Rusty duty. For a week and a half, we were out attempting to catch rusty blackbirds at the McClelland Lake Study Site.

Pink Lady’s Slipper (Cypripedium acaule)

Canadian Toad (Bufo hemiophrys) hiding in the moss

Background: As part of the Smithsonian’s Migratory Connectivity Project, members of the International Rusty Blackbird Working Group have been deploying archival GPS tags on Rusties since 2015 at sites in Alaska, Alberta, and New Hampshire.  These tags allow us to track migration routes and timing, and to locate wintering grounds for different breeding populations, but the birds must be recaptured the following year to retrieve the GPS data.  At the McClelland Lake breeding site in northern Alberta, we first deployed tags in 2015 and recovered two of these tags in 2016.  These tags showed similar flight paths and wintering ground sites, so we deployed another round of tags in 2017 to confirm the migratory connectivity of the Alberta population.  This year we returned to the site to attempt to find and recapture some of these tagged birds. This is where we were on June 3rd during the Great Canadian Birdathon!

Jeeves getting a PinPoint GPS tag in 2017

Cross-checking colour band combinations so we know who to catch again

Morning

We left our campsite early and headed off into the Treed Fen where the Rusty Blackbirds breed. On the way we passed through upland Jack Pine forest where we heard Western Tanager, Western Wood-Pewee and Olive-sided Flycatcher; Trembling Aspen copses, where we encountered Least flycatcher, Swainson’s Thrush and Red-eyed Vireos; and every type of burnt forest, where we saw Black-backed Woodpecker, Orange-crowned Warbler and Mountain Bluebird.  Once we reached the fen we suited up with waders and gear and headed to our nest searching locations. We already knew where two nest locations were. Jeeves and Arthur had both come back to nest within a square kilometer of their nests last year.  Wooster and Guinevere, however, had yet to be relocated.  

To catch the returning Rusty Blackbirds we first had to find their nests. At this time of year, they should mostly have been feeding chicks, so we thought that they’d be easier to both find and catch. We were right about at least the finding part. We found four nests that day, one of which was from a female who we had banded the year before. Unfortunately, she didn’t have a PinPoint GPS tag so we weren’t any closer to reaching our goal. While looking for nests we noticed some heavy swallow migration as large numbers of Bank, Tree, Cliff and Barns flew low over the black spruce. While they picked off uppity gnats the Cliffs sang their rattling and sputtery songs.

Jeeves’ nest with 5 chicks nearly ready to fledge

Wandering along a fresh seismic through our study site

Afternoon

As we weren’t finding any new colour banded birds we decided to head out to the edge of the fen where moss meets lake. Many of the Rusties come out to feed here on the large hatches of dragonflies that erupt in early June. Along the shore we saw a handful of ducks, shorebirds, gulls and terns. Exoskeletons from dragonflies first taking flight littered the reeds. In some patches you could easily count over a hundred skeletons in a single square meter of sedge. Blackbirds were coming out in small flocks to feed still, but we couldn’t spot any banded birds so we headed back to camp.

A small segment of the many dragonfly exoskeletons after an emergence along McClelland Lake

Burns featured prominently in our travel to and from the fen

Our new route back to the trailer was probably a mistake. From years of blowdown since the last fire, all of the trails that seemed open on satellite imagery were now covered in fallen pine. White-throated Sparrows seemed to be the only birds still singing in the hot afternoon sun, so our trip back was both slow and uneventful.

Back from the fen after a long day we sat down for a pasta dinner and rested up for another week of Rusty work. We didn’t know then, but over the next several days we would manage to capture both Jeeves and Arthur, who brought back two functional tags detailing their annual travels.

Jeeves returned in good health with a record of his year on the GPS tag

Arthur (center), Jay (left) and Jeremiah (right) were all excited after tag removal

Post and photos by: Jeremiah Kennedy and Jay Wright

The Great Boreal Owl Adventure

In February 2018, the Bayne lab had several crews scattered over northern Alberta deploying autonomous recording units (ARUs) to detect owls, specifically Boreal Owls, for Jeremiah Kennedy’s MSc project. ARUs were deployed in a grid of 16, over a 2.4km2 area in places with historical Boreal Owl detections. Due to winter accessibility and logging activity, an ARU grid needed to be moved. The field crew in northwest Alberta (Connor Charchuk, Lauren Law, Ben Paulsen, and myself) decided to do evening playbacks for Boreal Owls to best locate a new place to deploy a grid. Connor highlighted a couple areas he thought we should check out and around 8pm, we set out to start our search.

The playback protocol consisted of three parts: (1) Listen for 2min, (2) Play the song of the Boreal Owl for 2min, (3) Listen for 2min. We tried not to get our expectations up for finding a Boreal Owl, as most owl playback attempts are not successful. We turned off Highway 88 north of Red Earth Creek and headed west down a side road. A kilometer in, we started our search. The plan was to try a playback at each kilometer. The first playback was unsuccessful, but we expected most to be. The second stop was silent for the first two phases, and in the final seconds of the post-playback listening, Connor and I looked at each other with wonderment in our eyes. “Did you hear that?” he asked. “Yeah, what was that?” I replied. We both heard a soft, single call in the far distance, not the typical sound an owl makes. Optimistically, we thought it could be the contact call of a Boreal Owl responding to our playback. “Let’s go check this out” I suggested, and so we walked down the road to where we thought the call had come from. “Alright, play the song again” Connor prompted. Connor played the call from his phone and Ben remarked, “Oh look! A bat just flew overhead!” (I can’t make this stuff up). Ben. This is northern Alberta in February. There are no bats. WAIT! THERE ARE NO BATS! WHAT COULD THAT HAVE BEEN?! Ben shone his flashlight on a group of trees on the other side of the road to where he thought the creature flew to. “THERE IT IS! OVER THERE! SHINE YOUR LIGHT OVER THERE!” Connor exclaimed. There it was. A Boreal Owl perched in a tree no more than 20 feet away!

Figure 1. Boreal Owl in aspen tree, inspecting the singing owl coming from our playback. Photo: Natasha Annich.

We jumped and celebrated in excitement! High-fives, hugs, and shouts of joy were abound. The Boreal Owl is one of the boreal forest’s most elusive critters. The bird has a characteristic staccato song that is heard far more frequently than the owl is ever seen, but even then, it can be a challenge to find. Boreal Owls are poorly understood, and most banding records are sparse and incidental. They may follow migratory patterns of Northern Saw-whet Owls, but no one knows for sure. Anyway, back to the story. We watched this owl for several minutes, and it even swooped back across the road nearly taking out my eye on the way – yes, I literally had to duck out of the way! Then it perched in a patch of black spruce and with four flashlights and my iPhone, we managed to snap a somewhat identifiable photo of it:

Figure 2. Boreal Owl in black spruce, inspecting the singing owl coming from our playback. Photo: Natasha Annich.

We decided we had pestered the bird long enough, and got back in the truck. Connor then realized he had forgotten to take a GPS point, so got back out of the truck to go mark the waypoint. He then came running back, “she’s calling! Come have a listen!” So, we all got back out to listen to her contact calls – something none of us had ever heard before. Connor managed to record the call the owl was making and while we were all listening attentively, we heard another owl singing off in the distance in response! We concluded that the bird we were watching must have been the female, and the male was off in the distance. It was the perfect spot to build a grid for Jeremiah’s MSc project! Stay tuned to find out what he found.

 

Smart system for detecting owls: Automated technology identifies calls of Barred Owls, Boreal Owls, and Great Horned Owls

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An autonomous recording unit deployed in the field to record owl calls.

PhD student Julia Shonfield in Erin Bayne’s lab at the University of Alberta has developed an automated system for detecting owl calls, eliminating the need for researchers to spend nights in the field to survey owls. This new approach combines using audio recorders with a software program that can detect owl calls, called recognizers, and is similarly accurate and far more efficient than other, more traditional methods.

For more details of this work, see the university press release here:
https://www.ualberta.ca/science/science-news/2018/april/automated-system-detects-owl-calls

To hear Julia Shonfield talk about owls and her research, check out a clip of a radio interview on the local CBC Edmonton station: http://www.cbc.ca/listen/shows/radio-active/segment/15537010

“Utility of automated species recognition for acoustic monitoring of owls” by Julia Shonfield, Sarah Heemskerk, and Erin M. Bayne was published in the March 2018 issue of the Journal of Raptor Research, available at https://doi.org/10.3356/JRR-17-52.1.

Owl Calls 101

This is the time of year to get outdoors and listen for owls calling. From mid-March to early May is owl breeding season in northern Alberta, so they’re actively calling to defend their territories. In previous years, I would be out right now doing owl surveys for my PhD research, but this year I’m stuck in my office trying to finish writing my thesis. You may not have seen very many owls, but they are out there, and you’re far more likely to hear them than you are to see them. Owl species have easily recognized calls, and learning them is pretty easy because they are so distinctive. So for all of you that are interested in learning owl calls or heard one recently and want to find out what species it is, here is an easy guide to owl calls! Below are details for species found in northern Alberta with clips from recordings I’ve collected during my PhD research over the past few spring seasons.

For best listening of these clips use headphones and increase the volume if need be, some clips are more faint than others‎.

Great horned owl

You all know this one! This is probably the most typical sounding owl call. It consists of 4-5 hoots in a distinct pattern. Both the female and male will call in duets, and they’re relatively easy to tell apart, the female call is a bit higher in frequency (i.e. pitch) than the male. Great horned owls are very common, so you’ve got a good chance of hearing one. They are Alberta’s official bird, a great choice considering they are found everywhere in Alberta and in almost every kind of habitat. In the first clip you can here a female Great horned owl calling very close, and in the second clip you can hear a male and female duet:

Great horned owl female:

Great horned owl male and female calling in a duet:

Barred owl

Barred owls will also call in duets, though it’s harder to distinguish the male and female calls of this species. Their typical territorial call is the two-phrased hoot, commonly referred to by its mnemonic: “Who cooks for you, who cooks for you all?”

Have a listen to this clip and see if you recognize this call:

Barred owl two-phrased hoot:

Another call that can be often by heard is the ascending hoot, this call has a similar ending as the two-phrased hoot. Here is a clip of what that sounds like:

Barred owl ascending hoot:

 

Great gray owl

This species of owl has the lowest frequency call of all the owls found in northern Alberta. It consists of several low hoots in fairly rapid succession. Take a listen to this clip of a great gray owl male calling:

Great gray owl male calling (with a boreal owl calling in the background):

The female great gray owl will also give a ‘whoop’ call, this isn’t very commonly heard, but it sounds pretty neat. Here’s a clip of the ‘whoop’ call:

Great gray owl female ‘whoop’ call:

 

Boreal owl

This species tends to call quite consistently. They are generally found in coniferous forest and are relatively common in the boreal forest of northern Alberta. Its call sounds like a trill:

Boreal owl call:

 

Northern saw-whet owl

The sound of this species call sounds like the backup beep of a truck reversing:

Northern saw-whet owl call:

 

Northern pygmy owl

This species is more commonly found in the western part of the province in the foothills and mountains, however I have heard them in northeastern Alberta as well. This is Alberta’s smallest owl species. They are active and hunt during the day and can be heard calling during the day as well. This species call is quite similar to the Northern saw-whet owl but with greater spacing between the hoots:

Northern pygmy owl call:

 

Long-eared owl

This species’ call is probably the most boring owl call, but it’s exciting to hear them because they are not too common. It gives a series of simple hoots that are fairly widely spaced out:

Long-eared owl call:

 

Julia Shonfield is a PhD student in Erin Bayne’s lab researching the impacts of industrial disturbance on owl habitat use and distribution in relation to oil and gas infrastructure in northeastern Alberta. For her research she conducts owl acoustic surveys and has focused on three of the species mentioned above: great horned owls, barred owls, and boreal owls.

Field Fun Friday

What do -38°C, a spacesuit and a wooden post have to do with songbird research?
I could only hold the camera for a couple seconds before my fingers froze. My field partner, Logan, and I had just snowmobiled a half an hour from our truck parked on an ice road ~80 km south of the Nunavut border, in the tundra of the NWT. We were not actually wearing spacesuits, but our big onesies, snowmobile helmets and steel-toed winter boots made it look like we were. Our task was to collect acoustic recording units (ARUs) deployed by Environment & Climate Change Canada (ECCC). The ARUs were deployed last year when the ice road was open, but started recording in the spring, after birds had arrived. Winter is the only time this northern boreal/tundra transition area is accessible. 100 ARUs, mounted on trees and wooden posts (when there are no trees), span a 400 km south-north transect along the ice road. After retrieval, recordings will be analyzed to identify bird species. This marks the start of a long-term monitoring project to identify and track the northern limits of songbird ranges, a topic of great importance in the face of a changing climate. Students from Dr. Erin Bayne’s lab collaborate with ECCC on songbird research using ARUs.
Collaborators: Samuel Haché (Environment and Climate Change Canada)
Location: Tibbitt to Contwoyto winter road, Northwest Territories

-Post and Photo by Emily Upham-Mills

The role of urban scavengers in estimating the number of birds killed by window collisions

Most people can remember an instance where a bird collided with one of the windows of their home. Most people don’t know is that this has been identified as one of the largest human-related causes of bird deaths in Canada. Many studies have attempted to estimate the exact number of mortalities however, instead of coming up with an accurate number, multiple biases have been identified. The largest of which being the removal of a dead bird from below a window by a scavenger before it can be recorded.


-A house cat drags a bird carcass away from a window where it had collided

The number of birds being removed by scavengers has been accounted for in previous estimates, however these previous scavenger studies have all taken place at wind turbines. There have been few carcass removal studies done in an urban environment and none of these have been used to determine a correction factor that can be used in determining a more accurate window collision estimate.

To learn more about the role scavengers play in an urban environment we conducted a carcass removal study at houses within Edmonton throughout 2015. The premise was simple: a dead bird and a time-lapse camera were placed below a window in the front yard of each house. After 1 week we returned to see if the carcass had been removed.

In the end 67.5% of carcasses were removed within 1 week, with the average time to removal being 3.46 days. The most common scavengers were Black-billed Magpies (61.6% of removals) and domestic or feral cats (16.1% of removals). There were also removals by American Crows, Blue Jays and Red squirrels.


-Black-billed magpies and squirrels were some of the scavengers responsible for removing bird carcasses from collision sites

Carcasses were less likely to be removed in the winter and the relative probability of a carcass removal was 7.6 times higher during mid-summer compared to mid-winter. Newer houses experienced a lower probability of removal compared to houses built before 1970. As well, developed neighbourhoods saw a lower probability of removal than undeveloped ones. These factors are similar to those factors we had previously identified as having a large effect on the likelihood of a bird-window collision suggesting those homes experiencing a larger number of collisions are also experiencing a higher number of scavenging events.

From these results, we came up with a correction factor for carcass removal by scavengers. 31.8% of carcasses were removed in the first 24 hours, which results in a 1.47 carcass removal rate. This means the number of carcasses detected in the first 24 hours needs to be adjusted by 1.47 to account for removal by scavengers. This rate is lower than the one developed from wind turbine studies that was used in creating the current estimate of bird-window collision mortality in Canada.

Using this removal rate and the citizen science data previously collected by the Birds and Windows project we estimated 957,440 (± 59,280 SD) birds are killed from window collisions at houses in Alberta each year. This is the most detailed estimate of bird-window collision fatalities in Canada as it’s based on the most detailed window collision study at houses to date and a carcass removal study located in the same area. Unlike previous studies, we did not extrapolate our results across the country. Our estimate is for Alberta, the area from which the data was collected. If we are to improve the current bird-window collision mortality estimate for Canada, more localized studies like ours are needed. Completing studies in each of the provinces will help reduce several of the existing biases in the fatality estimate at houses.

-Post and photos by Justine Kummer

Link to full text: http://www.ace-eco.org/vol11/iss2/art12/

Kummer, J. A., C. J. Nordell, T. M. Berry, C. V. Collins, C. R. L. Tse, and E. M. Bayne. 2016. Use of bird carcass removals by urban scavengers to adjust bird-window collision estimates. Avian Conservation and Ecology 11(2):12.

Volunteering in the Owlery for the annual School of Witchcraft and Wizardry event

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Lively looking owl specimens demonstrate to kids a wide variety of species

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Special adaptations of their wings, skull, and talons, make owls formidable predators

Several grad students in our lab helped run the owlery again this year at School of Witchcraft and Wizardry, an annual science outreach event run by Let’s Talk Science at the University of Alberta. We taught kids a variety of facts about owls including how they are adapted to their environment, how they hunt, and how they communicate.

The students got to listen to several different species calls recorded from the wild. We had a variety of owl specimens and new this year we brought in mammal specimens (a hare, mouse, vole, and a squirrel), to show the kids what kinds of prey owls will eat. The kids really seemed to enjoy it and so did we! It was great seeing their eyes light up as they learned about owls and listened to different owl calls, there was even one kid that did a great impression of the calls of four different owl species!

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Participants listened to audio recordings of owl calls

Photos and text by Julia Shonfield