A small group of people turned out to hear an overview of FOCI’s Western Screech Owl Project at Mansons Hall on Friday September 27, 2024. Participants listened to different owl calls, examined owl feathers and learned why putting up nest boxes is important. The speakers were the two biologists from Madrone Environmental who wrote FOCI’s final report. Cortes Currents interviewed the lead author, Roxan Chicalo, afterward.  

“What gets me up in the morning, when I’m working at these species at risk, is thinking about balanced ecosystems. Everything is working together to create the ecosystem that supports our lifestyles as humans. In my mind, every animal and plant has a role that they play,” she began.

“Screech owls are a small avian predator. They eat  anything from amphibians to small mammals to fish, insects, slugs,  all sorts  of different small animals in the ecosystem. As a predator, they  keep a check on those prey species populations so that they don’t get out of control, and they also support biodiversity. If one of these prey species booms in their populations, they might start to compete against  other populations of other animals. We might see that we’re having more extinction events.  That’s why we should care to  promote a balanced ecosystem and support that.” 

Cortes Currents: How scarce are Western Screech Owls?  

Roxan Chicalo: “There’s not a whole lot of recent data regarding population estimates for Western screech owls. So first I would like to talk about the two subspecies that exist in British Columbia.  There’s the Megascops kennicottii kennicottii subspecies, the coastal subspecies.  They go  up to the south coast of Alaska, and  all the way down the coast to northern Oregon.  Then we have an interior subspecies,  the MacFarlane’s Western Screech Owl. Their range is just  a little bit into the Kelowna-Okanagan area.  Today I’m mostly talking about the coastal subspecies that we would have on Vancouver Island and the Discovery Islands.  The most recent population estimate from the COSEWIC report is about 2,000 individuals left in the wild and the range is between 1,500 to about 3,000.” 

“This data is heavily skewed from where these surveys have taken place.  There’s so many areas along the coast that are inaccessible or really expensive to access. A lot of the surveys were in Metro Vancouver, Vancouver Island around Victoria, a little bit on the Sunshine Coast, but not much further north than that.” 

“There have been some long term studies, specifically from the Christmas bird counts. Where they started documenting their owl counts in 1983, they detected an owl about one hour per hour survey time. I think the most recent estimate, a COSEWIC report from 2012, found about one owl for every 10 hours of survey effort.” 

“So there’s been about a 20% to 30% decline in the 15 years prior to 2012 and it’s suspected that that decline has continued, maybe have stabilized a little bit. Nobody really knows, but there are recent efforts by the government to conduct an inventory of what is happening now with those populations.” 

Cortes Currents: Has the Screech Owl been driven out of areas like southern Cortes Island by human development and predation from larger owls?

Roxan Chicalo: “Habitat loss is a big one, not just for Screech Owls, but for many animals. As far as Cortes Island is concerned, I imagine that there’s human development and forestry, which I think both lead to habitat loss in the way of cutting down wildlife trees or maybe not letting forests get to a state where they are naturally creating wildlife trees.”

“Maybe you have a snag or a rotten standing tree in your yard and you think, ‘wow, that thing’s very unsightly’ and ‘oh, it could be dangerous.’  So people cut them down. They don’t understand the role that those trees play for, not just Screech Owls, but other birds,  all sorts of animals, insects and fungus.”

“As far as forestry is concerned, if there’s still high demand for wood the forest companies might be compelled to cut  forests before they get to an age where these forests are going to start producing wildlife trees.”

“Once you get into the mature old growth: that’s when trees start to decay and then new ones start to grow. You have  a complex  understory with different layers and trees decaying at different rates.  If forests never get to that point where they’re starting to do that naturally,  there’s not going to be any homes for Screech Owls and other birds.” 

“There seems to be quite a focus on predation by Barred Owls. I think they’ve seen this specifically through the Christmas Bird Counts, where the number of Barred Owls detected in their surveys have increased concurrently with the decline of screech owls. Barred Owls are a known predator. They will eat Screech Owls and so perhaps Screech Owls are having to find little refugia habitats which Barred Owls don’t really occupy, except that Barred Owls are such great generalists. They can be successful in almost any type of habitat.”   

“There’s been talk about culls of Barred Owls to specifically help Spotted Owls, but maybe that’s going to help some of these small owls survive.” 

Cortes Currents: I read that Barred Owls are found in more human populated areas. 

Roxan Chicalo: “I don’t know if you’d be more likely to find them there. I think they are reported quite  frequently in those areas because they’re closer to people and so people report them, but I’ve seen them on the Brooks Peninsula in the middle of nowhere.”

“We do Screech Owl surveys using autonomous recording units. We stick these little microphones in the forest. They are on a preset schedule to record when owls are most vocal, so around sunset and throughout the night and into sunrise. We’ve been finding Barred Owls at almost all of our stations, no matter where we put them.

Cortes Currents: Tell us about your research in Campbell River

Roxan Chicalo: “We are still working on that project. It’s a collaboration between us biologists at Madrone and the We Wai Kai Guardians. We’re working in the Campbell River watershed, first of all, to survey for Screech Owls.”

“Surveys for Screech Owls started in the early 2000s and a number of territories were found.  This project has been picked up periodically and then most recently, we’ve conducted some area surveys along those historical transects that were surveyed in the early 2000s and we found no Screech Owls, not one.  That’s a little bit disconcerting. So we’re trying to understand that.”  

“We’re also serving new areas. We created a habitat model, to help guide  where our next surveys should be. We’ve done another four transects,  and we are analyzing those data right now.” 

“So far, we’ve  analyzed  25 stations and we’ve had about 5 stations with Screech Owl detection. That’s exciting, but we did have to conduct these surveys a little bit further afield. These previous surveys were done fairly close to Campbell River, near the Strathcona Dam and in the Quinsam forest area. Those ones are a little bit closer to human development and the ones that we’ve just done are way out there in the Sayward forest.”  

Cortes Currents: Was there a lot of old growth in all five of the areas where Screech Owls were found?

Roxan Chicalo: “It’s hard to say because the units are put about 50 to 100 metres off the road, and it’s next to an area where there’s an old growth management.  They’re called OGMAs (Old-growth Management Area), and OGMAs usually track along river valleys.  Sometimes there’s a thin strip of old growth remnants that have been left there. Sometimes our stations have ended up in these OGMAs, and sometimes they’ve ended up in 60 year old conifer dominated forests just adjacent to those OGMAs. So, those Screech Owls are probably living in those OGMAs. I think an old growth component is probably important for this species.” 

Cortes Currents: Are there any anecdotes that you want to talk about in terms of  methodology, results, or personal experiences?  

Roxan Chicalo: “Owls can be funny.  When you’re searching for them, you don’t always find them. Then when you’re not searching for them, there they are. I feel like that is maybe the case with most birds.”

“We were doing an environmental assessment on Valdes Island, in the Gulf Island area. I had made this terrible plan. I thought it was a great plan. We were going to do a late evening owl survey and then the next morning we’d wake up very early and do an early morning songbird survey.”  

“This was  early June, when it didn’t get dark until like 10pm.  So we had to stay up really late to do  this owl survey. We brought a speaker with us, and we would broadcast the male territorial call in hopes to get another male in the area, all fired up to respond.  So we stayed up late and didn’t get any responses.  We’re like,’ ‘Oh, darn, the habitat here is pretty good. There’s like a bunch of wetlands and a bunch of snags and I really suspected that they could be there. I guess they’re either not here or they’re not responding to us.’ So we went to sleep.” 

“In the middle of the night, I woke up and over my tent I could hear a family of Screech Owls. I could hear the babies begging and the parents hooting at them. They just passed over my tent and off they went.” 

“So I woke up at 4 AM to start the breeding bird survey. I was like, was that a dream?  What was that?  I swear that’s what I heard. So I questioned myself a little bit and then after I was like, ‘nope, I definitely woke up and that is what I heard.’ So  now we know that there’s a breeding territory there.”

Cortes Currents: Tell us about the work on Cortes.   

Roxan Chicalo: “I ran the analysis for the ARU data, and then I wrote the final report on behalf of the Friends of Cortes Island (FOCI).  The field work was done by Helen Hall, Sabina Leader Mense and Autumn Barret Morgan. They did a combination of call playback surveys, where they broadcasted the male territorial calls. In order for their data to be statistically significant, they had to redo these call playback surveys at least three times. So it was a significant amount of effort to go along to these different parts of Cortes and visit between six to ten stations in a night and broadcast these calls.” 

“They also deployed ARUs  and while they were up in the north end along an area called Bullock’s Bluff,  they detected Screech Owls at three different call playback stations. One of those stations was across the channel on Read Island.  So they did the call playback stations by boat at night. That also seems quite logistically difficult and adventurous, awesome to hear about.” 

“They also paired those efforts with ARU surveys higher up along Bullock’s Bluff.  The call playback surveys were right along the sea edge because they were by boat. The ARU surveys were by foot,  about between four to six hundred meters away from the coastline  and those ARU surveys didn’t detect a single Screech Owl.” 

“The habitat where these ARUs were was good. They had little old growth remnants, like some big Douglas fir trees among some hemlock and smaller Douglas fir trees.  There are cavities up there. Screech Owls are secondary cavity nesters. They rely on Pileated woodpeckers and Northern flickers to excavate holes in dead standing trees. Then the owls nest in these cavities.” 

“I would have expected that they would be up in these old growth vet areas. So  why did the ARUs not detect them? Are the screech owls not going up the slope where these old growth vets are?The area around there is fairly dry.  We don’t really expect to see Screech Owls in dry habitat since they’re  more of a riparian dependent species.”

“Maybe there’s cavity opportunities down closer to the shoreline. Maybe the owls are taking advantage of the intertidal zone for their prey. Maybe they’re eating fish and sea cucumbers.”

“Where are they spending their time? What does their home range look like? How are they making a living? It’s going to be very interesting to hopefully continue this work and dig into what is going on with those Screech Owl territories.”

Cortes Currents: What’s the next step?

Roxan Chicalo: “The next step is to work with Helen to  get some more grants to acquire funding to continue this work. There’s hope that the Kennicottii subspecies will be listed under the Forest Range and Practices Act (FREPA),  and  they will be able to have special protections for them. So on Crown land they’ll be able to create wildlife habitat areas and then no logging can happen there.” 

“We don’t know where many of these Screech Owl territories are, and we don’t know  what components within the habitat there that they’re relying on.”

“So any information that we can gather through work like what the Friends of Cortes Island have been working on is going to be really helpful to inform those initiatives.”  

“I do want to bring attention to the role of citizen scientists, the naturalists on the island, people that  like to go camping and people that are out hiking or observing animals.  I really want to draw attention to the importance of reporting your observations.” 

 “As a biologist, let’s say I’m doing an environmental assessment for a sandstone quarry.  I’m going to  the conservation data centre to see where there’s been observations. So I see there’s been a Screech Owl detected here by someone.  I will have to include that in my report. I will have to create mitigations and prescriptions for them to manage this potential habitat for Screech Owl that they may be impacting.”

“It’s really important to submit your observations because people actually use them and things happen from them.” 

Links of Interest:

• Western Screech-owl Inventory and Habitat Stewardship on the Discovery Islands, British Columbia – Madrone Environmental (2024)
• COSEWIC Assessment and Status Report on the Western Screech-Owl kennicottii subspecies Megascops kennicottii kennicottii and the Western Screech-Owl macfarlanei subspecies Megascops kennicottii macfarlanei in Canada (2012)
• Articles about, or mentioning, FOCI’s Werstern Screech Owl Project
• Western Screech Owl Project page on Friends of Cortes Island website
• Madrone Environmental website

Top image credit: A Western Screech Owl peers down the tree trunk – photo credit Blair Dudeck

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