Oct. 20: Owling Season Wrap up

With the threat of 10mm of rain and a minimal reduction in gusting wind speeds down from 70+ kilometres per hour to between 30-40 I had to make the disappointing call to shut down the station for the season on October 15th.

This year’s extension of our Northern Saw-whet Owl monitoring program which ran from October 1st through to the 15th was made possible by a generous grant from the Cariboo Regional District (CRD). The aim of the extension was to ascertain if the peak of the “migration”/movement of this species occurs after we leave in September (i.e. October) and if so to evaluate the merit and feasibility (weather being the primary variable) of possibly extending this program in the future.

Local and long time friend of the TLBO, Roma holding a Saw-whet

The Northern Saw-whet Owl monitoring program is very popular with locals and volunteers alike and provides an excellent opportunity for outreach, education and conservation awareness. We have yet to encounter a volunteer or visitor who has not fallen in love with these charismatic little creatures of the night! One of the TLBO’s goals is to inspire and nurture the public’s love of our feathered friends through education and hands-on experience. We place a special emphasis on the younger generations as they are key to the continuation of projects like the TLBO and other conservation and research initiatives across the globe. As I stated earlier, public interest in this program is high and we hosted a total of 50 visitors over 18 nights of owling which spanned from September 6th to October 12th. I should stress that all visitors were expected to adhere to current COVID-19 protocols whilst visiting the station so as to maintain a healthy and safe experience for all. October sessions, six in total, were very popular with 33 visitors overall with October 1st being the only night that was not attended by the public. September by contrast saw “only” 17 visitors who attended five of the 12 nights that we operated. Volunteer attendance was also high with at least one and up to two present on 17 of the 18 sessions. The volunteers for this program came from as far away as Williams Lake and Quesnel and as close as the valley proper as on two night’s during October I had help from locals Roma Shaughnessy and Jim Sims (of Eagle Lake).

Two of our Saw-whet volunteers, Courtney (left) and Mae (right).

In 2012 the TLBO began its Northern Saw-whet Owl monitoring program running an average of 10 nights each season through the month of September. Over the previous eight seasons the TLBO has banded a total of 238 owls with an average of roughly three owls banded per night. The range in owls banded per season runs from a low of 7 in 2013 to a high of 62 in 2019. Rodents are the predominant prey group for Saw-whets and as such their populations are intrinsically linked, numbers of both species peaking every four years. According to Rocky Point Bird Observatory who have a much more comprehensive Saw-whet Owl monitoring program than ours, 2017 was the last big year of the population cycle as they banded roughly 1800 Saw-whets between their two stations. That same year proved to be a big season for the TLBO program as we banded a record 59 owls over 12 nights. Strangely 2019 would break that record with 62 owls banded in just 11 nights. This year’s program produced our third highest September result with 54 owls banded during 12 nights.

I was optimistic that in October we would be able to owl most nights however the fabled Tatlayoko wind had other thoughts. Strong winds were our biggest obstacle along with two nights of rain as we would only be able to operate on six of the 15 nights. With that in mind we still caught a total of 79 owls during those six sessions! This works out to about 13 owls banded per night which is 10 more than our eight season average. Our lowest night came on October 1st where we banded a single owl which was likely due to the fact that there was persistent, moderately strong wind throughout the session. Otherwise, we broke the previous single night record of 15, which was first set back in 2017, on four separate occasions: October 3rd (16 banded), 6th (16 banded), 10th (22 banded) and 12th (18 banded). Throughout the entire 2021 program we banded a total of 133 owls over 18 nights with no recaptures. This brings our nine season total to 371 owls banded!

With respect to age ratios, 14% of our owls banded this year were adults with 11 second-years, 5 thirds-years and 3 after-second-years. Based on our rather limited data set, this percentage seems to be relatively high in a year where we would expect there to be more reproduction due to high rodent populations and thus an even higher percentage of hatch-year birds. To put this in context 2017 and 2019, both our biggest season’s with respect to capture numbers, saw our adult composition at only 8% and 5% respectively. There has been quite the range of adult/hatch-year ratios since we began with 2018 having the highest percentage of adults at 39%. Two thirds of these were second-years which validates the trend, coming on the back of a big reproduction year (2017). As we continue collecting data, each year we will be able to gain a stronger grasp on the trends of our Saw-whets Owls.

Volunteer Courtney (right) and yours truly (left) with a pair of Saw-whets.

Our Northern Saw-whet Owl program provides the most information with respect to connectivity, which increases our limited knowledge of the migratory strategies of this species. We have had 12 recoveries of owls that were first banded at the TLBO over the nine seasons that the program has been in operation the majority of which (8) have been at the Rocky Point Bird Observatory (RPBO). Otherwise we have had recoveries of our owls in Gibsons and Comox along with two in Washington State, USA. The first of these two international recoveries was in Colfax, near the Idaho border, 739km away whilst the second was on Bainsbridge Island (near Seattle) which is relatively nearer at 439 km away in a straight line and fits with the pattern of our other coastal recoveries. So far this season the RPBO Saw-whet program has recaptured four of our owls! The first of these was a female banded as a hatch-year on September 10th, 2020 and recaptured on October 4th 2021. The second was a hatch-year female that we banded on October 2nd, 2021 and was subsequently recaptured at RPBO nine days later on the 11th! The third recapture was a second-year female that we banded on October 10th, who was recaptured on October 19th. The fourth was banded September 15th, 2021 and recaptured October 20th! Needless to say, this connectivity between stations is very interesting as a pattern has begun to emerge which indicates that it takes roughly 9-12 days for a bird that we banded in the Tatlayoko Valley to then be recaptured at RPBO in Metchosin on Vancouver Island. In a straight line, this is about a 374 kilometre flight. We are very interested to know what route these owls take to get down to the island and suspect that they likely follow the Homathko out to Bute Inlet and subsequently island-hop over to Vancouver Island, around Campbell River, and then head southwards (this route would be around 450km to RPBO). 

A rare glimpse of the banding process.

To further investigate the movements of these intriguing owls on their migration the TLBO entered into a joint MOTUS tracking pilot project with the RPBO and Eric Demers at the Vancouver Island University (VIU) by affixing MOTUS tracking tags to owls. We affixed tags to nine owls in September as well as setting up a receiving tower on Skinner ridge, 5km north of the TLBO, in late August. Thus far we don’t have any data to share but stay tuned as with any luck one of our owls will pass by another researcher’s tower on their flight southwards!

Once again we would like to thank the CRD for the funding to go ahead with this pilot extension of our Northern Saw-whet Owl banding program, the Canadian Wildlife Service for providing us with all the necessary equipment to set up a MOTUS receiving tower, Michal Smialowski for all his expertise, energy and time in the set up of the receiving equipment, the Public Conservation Assistance Fund for the necessary grant that allowed us to purchase the MOTUS tags and finally, the Tatlayoko Field Station Society for taking on and administering the project and the TLBO in general.

Until Next season.

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Oct. 9: Owling Season Midpoint Update

Northern Saw-whet Owl Monitoring:

The Tatlayoko Valley which in the Tsilhqot’in language means, “Lake of the Big Winds” has been true to its name since my last post. Over the past four nights we have been hampered by wind along with one night of rain making for only a single night of owling. That said that night (October 6th) was near perfect with a light breeze and only a smattering of clouds in an otherwise crisp night sky. This was Courtney and Mae’s first and thus far only night of owling since they both arrived on the 5th and they would not be disappointed! Despite it being a school night we were also joined by Kelly and her four children who were immediately rewarded by good looks at an inquisitive Saw-whet as it perched above net 1. Bolstered by what only could be a good omen we arrived at the nets to find two lovely hatch-years. Delighted the Emke’s headed back home leaving the three of use to continue on to the next net check where we would get eight owls!

What do you call four handfuls of Owls? Perhaps 8? Needless to say the smiles speak volumes.

Subsequent rounds yielded a further six owls for a total of 16 which tied our previous single session record set by Jim and I on October 3rd. The plethora of owls provided lots of handling practice for both Mae and Courtney as they would have the pleasure of each banding two. Of the 16 birds banded 15 were hatch-years while a single second-year provided some much appreciated contrast. With this effort our season total now sits at 93 Saw-whets banded and an all time total of 332 banded since the program began in 2012. The extension to our owl banding program began October 1st and thus far we have banded 39 owls over the course four nights for an average of roughly 10 Saw-whets per night which is well above our 8 year average of three birds per night. Here’s to hoping that we get a stretch of suitable weather and lots more Saw-whets over this coming week!

To see the eBird checklist for October 6th’s owling session click on the link: https://ebird.org/checklist/S95714409

Opportunistic Songbird Banding and Migration Monitoring:

I have continued to do some opportunistic songbird banding whenever the weather cooperates. This has provided a nice counterpoint to the owl banding as despite there seeming to be a plethora of migrating sparrows (mainly members of the genus Zonotrichia which I will get into later) and an every diminishing number of Yellow-rumped Warblers (of both subspecies) the station has been mainly inhabited by residents. As the season has worn on I have noted a marked increase in the presence of both Golden-crowned Kinglets and Pacific Wrens in and around the station. This has been mirrored by the fact that in two short sessions of banding we caught 5 of the former and two of the latter.

As I eluded to earlier three members of the genus Zonotrichia namely, White-crowned, Golden-crowned and White-throated Sparrows have been present in the valley in relative abundance. Golden-crowned Sparrows which we generally only see in small flocks of 3-5 individuals in September are much more abundant this month with lots of flocks numbering in the double-digits at the field station, along the road and down at the banding station. White-crowned Sparrow numbers have seen some fluctuations but they largely seem to be the second most numerous whilst White-throated maintain their historical role of being the most sparse member of this genus in the valley. That said I did encounter a group of four foraging in a spruce stand on my way down to the banding station!

Mae with her first Pacific Wren

Sightings of note include my first Bufflehead and Gadwall in the valley this season as they were both out on the lagoon amidst a melange of the more commonly encountered duck species. On October 7th, whilst birding around the station I flushed my first Lapland Longspur of the season as it emitted first its “rattle” call followed by its “teew” call. This beautiful breeder of the arctic tundra often goes unnoticed in the valley on migration as we have only had 12 detection’s during 15 seasons of monitoring. As luck would have it I flushed a Lapland Longspur today as I was traversing the south field. Whether it was the same individual or another migrant will remain unknown but it is always a delight to encounter one. To encounter one virtually and get a sense of what I mean by the “rattle” and “teew” calls click HERE. The only other sighting of note was a Blue Jay that I heard before catching brief glimpses as it flew overhead on October 8th. Three days earlier our neighbours Don and Audra reported one at their feeder and later on the 8th Roma had one visit her feeder. Presumably this is the same individual that has been making the rounds in the valley. This often nomadic species is rather scarce in the valley proper as during our 15 seasons of migration monitoring we have only had 4 detection’s two of which were likely of the same bird in 2020. 

Finally I participated in the Cornell Lab of Ornithology’s “October Global Big Day” event logging 40 species consisting of 484 individual birds all in a rather deafening  30-40km/hr wind that reportedly reached gusts of 80km/hr.

My daytime sightings spanning October 5th-9th:

October 5th: Observations

October 6th: a) Census b)Banding

October 7th: a) Census b) Observations

October 8th: Banding

October 9th: a) Observations b) Census and Observations

 

 

 

 

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Oct. 5: Owling Season Update

Northern Saw-whet Owl Monitoring:

It has been a week since we wrapped up our 2021 fall migration monitoring program and now have fully moved our focus onto the Northern Saw-whet Owl program. The aim of this two week pilot extension of our normal owl monitoring is to ascertain if the peak of Saw-whet migration occurs in early October as we have long suspected.

Since the principle prey of Northern Saw-whet Owls are rodents it is thought that their numbers are tightly tied to the fluctuations in rodent populations which peak every four years.  The last big Saw-whet Owl year was 2017 so it is expected that 2021 will see large numbers of Saw-whets on the move again thus providing further rationale for the extension of our owl banding program.

Through the month of September we were able to get out and owl on 12 nights, banding a total of 54 birds which is our third highest behind 2017 (59 birds banded over 12 nights) and 2019 (62 birds banded over 11 nights). Thus far in October we have banded 23 owls over the course of three nights bringing our 2021 total to 77 banded. On September 30th we stayed open an extra hour banding a total of 15 individuals which tied our most owls banded in a single evening which was first set on September 13th, 2017. On October 3rd I was joined by local Eagle Lake birder Jim Sims for a night that fit all three of our criteria for perfect owl migration conditions, namely, cold, calm and clear. It was a fantastic night as we would go on to beat the single session record by one with 16 owls banded (two second-years and 14 hatch-years) over three hours with several more individuals calling as we closed our nets.

One of the 16 Northern Saw-whet Owls that we banded on Oct. 3rd

MOTUS Project Update:

On September 30th, Avery’s last night in the valley we deployed our four remaining tags so all of our MOTUS tags are on owls. Before I leave in mid October I will be doing a second data download at which point we will be able to see if any are still in the valley. By that point we may even have detection’s of our owls by other towers! Stay tuned.

Recapture UPDATE:

Last night (October 4th) at Rocky Point’s Pedder Bay station Jannaca Chick recaptured a second-year female Northern Saw-whet Owl that we banded on September 10th, 2020 as a hatch-year. This is pretty exciting as they are the only station to recapture our owls and I believe that this is the 6th one to date.

Recaptured TLBO Northern Saw-whet Owl at Rocky Point Bird Observatory. Photo credit: Jannaca Chick

Opportunistic Songbird Monitoring:

With my days mostly free I have been opportunistically banding songbirds when conditions are suitable. Thus far on two short days we have banded 28 passerines as well as three recaptures. Ruby-crowned Kinglets have made up the bulk with 10 banded whilst Savannah Sparrow, Song Sparrow and Yellow-rumped Warblers (two “Audubon’s” and one “Myrtle” subspecies) are the second most common with three banded respectively. Unsurprisingly the recaptures have all been Black-capped Chickadees which are a resident species and all of which were first banded earlier this season.

I have also endeavoured to continue birding our census route on a daily basis (weather permitting of course). Numbers and species have fluctuated by the day with continued dominance by Yellow-rumped Warblers (of both subspecies)- which are the most numerous species of the warbler clan – as they continue their movement southwards. The highlight thus far was yesterday when I observed a big movement of geese, mainly Snow Geese as I would log 357 individuals over the course of the morning along with roughly 100 Greater White-fronted Geese all moving south, the former in V’s of various sizes. This was quite the spectacle as we have only detected Snow Goose twice over the 15 season’s of monitoring (2013 and earlier in 2021) which is likely due to the fact that we leave before their migration truly begins. Near the end of the day an immature Golden Eagle would make a brief yet memorable appearance as it went after an immature Snow Goose that was foraging alone out in the north field. Mountain Bluebird flocks continue to frequent the valley as they begin to get ready for their migration southwards whilst mixed flocks of sparrows predominantly Songs have been seen all around the station.

One of the multiple V’s of Snow Geese that were observed on Oct. 4th

My daytime October sightings are listed below:

October 1st: a) Census b) Observations

October 2nd: Census and Observations

October 3rd: a) Census b) Observations

October 4th: a) Census b) Observations

As I write the rain is coming down and the snow line has descended halfway down Skinner Ridge whilst the Niuts are similarly clad. Who knows maybe we will have a blanket of snow in the valley bottom before too long.

Until the next update.

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Oct. 3: A Brief History of the TLBO

~Post by Andrew Harcombe (Founder and Volunteer)

This fall, my wife and I again visited the TLBO as volunteers for a week. Many years ago, myself and some biologists from the BC Conservation Data Centre were invited by Nature Conservancy of Canada (NCC) to visit the Tatlayoko Lake Ranch, a proposed acquisition by this national land trust. We were asked to provide some biological input for the project, with the purpose of providing assessed biodiversity values for such an investment. We concluded that values here would include breeding birds, grizzly bear habitat, support for adjacent ungulate winter range, and possible a migration corridor for fall passerines.

 A few years later, I joined regional NCC staff as a conservation biologist. One of my projects was to set up biodiversity monitoring of this ranch, the adjacent Lincoln Creek Ranch and nearby Skinner Meadows (also NCC properties). I had the great pleasure of contracting Cedar Mueller to do grizzly bear inventory in the valley, along with fall monitoring on the Chilko River to the east. She was assisted by her dad, Fritz (now the President of Tatlayoko Field Station Society TFSS).  I also set up a project to do some preliminary hydrological work on the area’s rivers and streams; this work was done by Sandy Hart (now a Director in the TFSS). Breeding bird work was done by Rick Howie (also author of the Tatlayoko Lake bird checklist), building on long-time work by Ruth and Charlie Travers. Finally, I investigated and set up TLBO as a fall bird migration monitoring project and as an operating member of the Canadian Migration Monitoring Network. The TLBO was in operation for 10 years as a NCC project and then continued to the present with support from BC Spaces for Nature and now the TFSS. All through these times, Peter and Roma Shaughnessy have provided project support, property maintenance, building design as well as building and now, Peter is the Project manager for TFSS.

Steve Ogle and I in the banding building (2014)

 

Since Day 1 of the TLBO, Gail and I have been volunteering for at least a week for every year except the past two. Gail and I were trained by the banders to be extractors (removers of birds from the mist nets that were subsequently banded). Gail especially has honed these skills, and we are now both active members of the Rocky Point Bird Observatory outside of Victoria. In Tatlayoko, we stayed first in the NCC yurt on the ranch and then in our trailer at Lincoln Creek Ranch.

Gail with her extracted Sharp-shinned Hawk (2021)

It is a small, interconnected world that has existed there well before that first visit to the valley. Supportive local people have further enhanced our whole experience. I am proud of the part we have played here and am happy to see the future of the TLBO now strongly supported by TFSS. From our first banders, Steve Ogle and Chris Chutter to the present Avery and Sachi, the birds have been in good hands. The daily blog has exposed the good work to anyone who wants to read it. Now the TLBO data is also being shared with eBird, a global database of bird observations.

Myself and one of TLBO’s first-caught Northern Saw-whet Owl (2013)

From humble beginnings under an open tent canopy to the present specially designed banding building with solar power, and now with a MOTUS installation, the TLBO has blossomed into a showpiece bird monitoring operation. Who could have predicted that all those years ago when I first saw the valley?

Andrew Harcombe

Retired Biologist

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