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

OLYMPUS DIGITAL CAMERA

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.

Field Fun Friday

With the spring breeding season right around the corner, here is a photo of three Ferruginous Hawk chicks during a routine nest check last summer. Nick Parayko is studying these amazing raptors, in southern Alberta, for his Master’s project under Dr. Erin Bayne. Looks like fun!

Photo by: Nick Parayko

 

 

 

Male red squirrels kill other squirrels’ offspring to increase their own chances of having kids

I was walking in the Yukon one evening when I heard a commotion in the forest. At the time, I was working on my PhD under the supervision of Stan Boutin at the University of Alberta as part of the Kluane Red Squirrel Project. This meant that I spent a lot of time hiking on my study area monitoring the red squirrels that I was working with. It is common to hear squirrels calling because they are pretty chatty, but this commotion was different: this squirrel was very upset.

I walked quickly towards the calls, arriving to find a female squirrel yelling at her male next-door neighbor, who had intruded onto her territory. This is unusual, as squirrels live solitary lives and are usually respectful of each other’s boundaries. However, as I watched the male’s intentions soon became clear because within seconds of my arrival the male killed one of the female’s pups. I realized that I had just witnessed infanticide.

SONY DSC

Infanticide is when an adult kills the young of their own species. I later found a second dead pup from the same litter, whose wounds were consistent with the infanticide that I had watched. The whole litter eventually died and their mother, the female I had seen yelling at the male, later had a second litter that summer. I was able to show using genetics that the male who killed the pup was not the father of any of the pups in the first litter, but that he was the father of all of the pups in her second litter.

This is an example of sexually-selected infanticide: this is when a male kills another male’s offspring in order to increase the chances that he’ll be able to father kids of his own when the female breeds again. I was fascinated by this behaviour, so I decided to explore it in more detail in our paper that was published today in the journal Ecology. I found evidence that this behaviour is linked to fluctuations in white spruce cones, the main food that red squirrels eat.

My colleagues previously showed that red squirrels can predict the future cone availability. The cones mature in autumn and at that time they can be harvested by the squirrels to be stored in a cache on their territory called a midden. Squirrel pups strike out on their own in the fall and during a bumper crop, called a mast year, they have a really good chance of surviving the winter because there are lots of cones for them to harvest and cache. Very few pups are able to store enough food in non-mast years so few of them will survive. Having access to cones is really key for pups to survive.

SONY DSC

Squirrels are strategic and they can predict the future cone availability. During a mast year, the females will have more than one litter because they know that their pups will have access to cones once the fall arrives, and thus the pups will have a good chance of surviving. The females respond to masts in this way even though they breed in the spring but the cones aren’t available until autumn. In contrast, during non-mast years they will typically have only one litter.

I showed that litters die more frequently during mast years, suggesting that infanticide is more common during mast years. When litters die, their mother is more likely to have a second litter and will breed again sooner than if her litter had survived. So male red squirrels commit infanticide in mast years because the females will have that second litter, giving the males a second chance at fatherhood.

SONY DSC

 

Post and photos by: Jess Haines

Effects of habitat quality and access management on the density of a recovering grizzly bear population

Clayton Lamb and colleagues from the Provincial Government of British Columbia and University of Alberta recently published an article in the Journal of Applied Ecology. This work investigates the factors driving the density of a threatened grizzly bear population in southern British Columbia.

Key results and conclusions:

  1. Heavily roaded areas had lower grizzly bear density.
  2. Closing roads to the public restored bear density in this area.
  3. Maintaining roadless areas in productive bear habitat is critical.
  4. Areas of low road density and high habitat quality occur as islands surrounded by either high road densities or poor habitat, limiting grizzly bear connectivity.

The Open Access article can be found here:

http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.13056/full

Infographic by Wild 49 Alumnus Kate Broadley, MSc.

An adventure in the far north – Deline, NWT

 Deline in the Sahtu region, NWT

One of the perks of graduate studies are opportunities to go to remote places that few other people get the chance to see. Earlier this summer I had the opportunity to travel to a remote fly-in only community in the Northwest Territory. The purpose of the trip was not directly related to my thesis, but to help start a local community bird monitoring program in two communities in the Sahtu region of the NWT, a project that the Bioacoustic Unit at the University of Alberta (http://bioacoustic.abmi.ca/) and my supervisor, Erin Bayne, is involved in. So in June, I travelled to Deline on the shores of the Great Bear Lake, and another graduate student, Michelle Knaggs travelled to Tulita on the MacKenzie River. Our roles were to bring autonomous recording units (ARUs) to the communities and start deploying them at various locations nearby with the help of locally hired guides.

The day I arrived in Deline was summer solstice and National Indigenous Day, and the following day was another holiday, Sahtu Day. The festivities involved a delicious BBQ cooked over a wood fire, a variety of games including egg tosses and obstacle courses, and a drum circle. These two days of local celebrations served as an excellent introduction to the community of Deline and gave me the opportunity to meet many of the locals.

In the week that I stayed there, I deployed the ARUs in several different locations around Deline. Though Deline is probably the furthest north I’ve ever been in Canada, the habitat was quite familiar. This area is still within the boreal forest, and the predominant habitat here is black spruce forest.

Black spruce forest in the area surrounding Deline

There were only a few roads and trails, so the access was relatively limited in the first couple of days because there was still so much ice on Great Bear Lake. Talking to people in the community, it was not that unusual to still have ice on the lake in mid-June, and it was largely dependent on the wind direction.

Ice on Great Bear Lake

Finally, the wind changed direction and pushed the ice out into the middle of the lake and away from the shores of Deline. In the last couple days I was there, I was able to get out by boat on Great Bear Lake and put some of the ARUs along the shore.

Boats along the shore of Great Bear Lake

The lake in the evenings was truly mesmerizing, flat as glass and incredibly clear, I could still see the rocky bottom several hundred meters out from shore. It was calm and peaceful being out in a boat on the lake in the evenings. The long days meant there was no rush to get things done before it got dark.

View of Deline from a very calm Great Bear Lake

There was a diversity of birds on the lake including Common Loons, and a variety of ducks such as Northern Pintails, Mergansers, and Scoters. In town, there were large numbers of Ravens and Herring Gulls.

A Raven and Herring Gull, abundant in town and especially at the town dump

It’ll be really interesting to see what birds we get on the recordings, the listening will be starting this fall. Since this area is so far north, it’s at the northern limit of the distribution of many birds. For me, it was a unique experience in the far north, one that I won’t soon forget.

  • Photos and blog post by Julia Shonfield