| a member of the Canadian Migration Monitoring Network

2020 Season during COVID-19

July 30, 2020

Hi everyone,

Our fall migration season will be starting on August 1st and continuing until October 15th as usual. However, our operations will work a bit differently this year due to COVID-19. We still need the help of our regular volunteers to keep things running smoothly, but the number of volunteers will be limited and our interactions will be modified.

Unfortunately we are also unable to accept visitors to the station at this time. With the recent increase in cases in various part of BC and other parts of Canada, having visitors presents a risk to station staff and volunteers. We don’t have the capacity to manage crowd control measures in addition to our regular banding operations. The situation will be monitored and updated as appropriate and information regarding visitor access will be posted on VLBO’s social media.

Being affiliated with the Canadian Wildlife Service requires us to follow relatively stringent protocols to ensure the safety of our staff, volunteers and birds. Due to the persistence of virus in the population, and particularly with recent local flare ups in the Okanagan, VLBO has developed a COVID-19 Exposure Control Plan for 2020 Operations with guidelines and modified protocols to guide staff, volunteers, and any organized groups that may arrive for work or activities at the Observatory. Unfortunately we will be unable to train any new volunteers to band or extract this season due to the need for close interactions with this process. This means we’ll have to rely even more heavily on our regular volunteers who are already experienced at extracting. Furthermore, having enough census volunteers will be critical as this will free up the banders to focus on banding operations. So if you have a few spare mornings in the next few months and are looking for a good birding opportunity, please take a census shift or two! In past season’s we’ve had a few volunteers commit to a weekly census shift which is extremely helpful for us banding staff.

vlbo-covid-19-exposure-control-plan-final Download

Anyone who wishes to volunteer must review the Exposure Control Plan and abide by its contents. Check out the volunteer page for more details. We’ll also be without the help of our banding lab this season; instead we will band at tables under a mesh tent. So plan accordingly for that – bring extra water, keep your food appropriately contained, and pack out any garbage. We’ll have a bear proof container to store food on site.

I’ve set up our volunteers SignUp for the 2020 season so please click here or go to the Volunteer page to sign up for shifts.

2020 Season Summary

November 11, 2020

by Matthias Bieber

Our 20^th season of fall migration monitoring was unpredictable and atypical in many ways but it finished with numbers in line with most recent seasons. August started with a bang with our busiest opening day ever – 150 birds in total! The first half of August was similarly busy to our record-breaking season last year with 776 birds banded by August 14^th, and we weren’t even able to open all of our nets due to high water levels until the third week. The second half of August was a different story, however. Slow days punctuated the rest of August and continued well into early September, which is usually a quiet period, but this year even more so than average. September was an unusual month as we didn’t see a typical peak around the middle of the month and then a drop off near the end. While the middle two weeks of September were slightly more productive than the rest, overall, daily numbers of birds banded were pretty evenly distributed with the second, third and fourth week totals being 190, 154, and 181, respectively. Figure 1 shows multiple peaks during the latter half of September compared to the overall station average value which declines after mid-September. October was highly variable this year with some very productive days and other slow days. Due to poor weather we were unable to open the nets on three days in October.

Figure 1. Number of birds banded and recaptured each day of the season compared to the daily station average.

While not comparable to last year’s record season, as a whole the 2020 season finished with 2121 birds banded of 63 species. This total makes it the 4^th most productive season ever after 2019, 2006, and 2018. This respectable total is largely thanks to our busy opening two weeks where we averaged 55 birds per day and 0.92 birds per net hour which is incredible! To put that into perspective, during the entirety of September we banded 754 birds, equal to 25 per day, and 0.34 per net hour. We finished the season with an average of 27.9 birds per day and 0.39 new birds per net hour (does not include recaptures). We finished the season with 494 recaptures which is a relatively lower total and the 7^th highest finish.

Figure 2. Cumulative total of birds banded through the season from 2006-2020 compared to the average.

This season was a mixed bag in terms of species totals. Some of our stalwart breeders continued on recent upward trends with productive seasons, like Cedar Waxwing, Yellow Warbler, American Goldfinch, and Marsh Wren, as did common migrants Lincoln’s Sparrow, Audubon’s Warbler, and Spotted Towhee. Some had relatively poor showings however, in particular Orange-crowned Warbler, Wilson’s Warbler, and many others had very average seasons. Yellow-breasted Chat, Cedar Waxwing, Lark Sparrow, Cooper’s Hawk set new season records, and Bewick’s Wren tied the record from 2016. American Tree Sparrow was the only new species for the station this year, and coincidentally also the last bird of the season. Additional rare captures included VLBO’s 2^nd Rose-breasted Grosbeak, 3^rd and 4^th Lark Sparrow, 9^th Mountain Chickadee, Gray Flycatcher, Golden-crowned Kinglet, two Fox Sparrow, and a Steller’s Jay recapture that was banded in 2014.

The Top 10 species this season, in order, were Lincoln’s Sparrow, Yellow Warbler, Cedar Waxwing, Common Yellowthroat, Gray Catbird, Song Sparrow, Audubon’s Warbler, Orange-crowned Warbler, Willow Flycatcher, and American Goldfinch.

Thanks to all the volunteers who helped out this year in spite of challenging times with the pandemic. You all helped to make it another successful season of fall migration monitoring!

The final species totals are as follows:

Species	Banded	Recaptures
Lincoln’s Sparrow	230	16
Yellow Warbler	189	19
Cedar Waxwing	188	7
Common Yellowthroat	188	80
Gray Catbird	183	54
Song Sparrow	179	122
Audubon’s Warbler	161	3
Orange-crowned Warbler	146	18
Willow Flycatcher	105	29
American Goldfinch	93	10
Ruby-crowned Kinglet	68	11
Marsh Wren	57	13
Spotted Towhee	26	3
Black-capped Chickadee	24	50
White-crowned Sparrow	20	4
Western Wood-pewee	20	2
Pine Siskin	19	2
Nashville Warbler	18	4
Wilson’s Warbler	13	1
Northern Waterthrush	12	1
Unidentified Yellow-rumped Warbler	12	2
Yellow-breasted Chat	12	6
Oregon Junco	11	2
MacGillivray’s Warbler	10	1
Myrtle Warbler	10	0
Bewick’s Wren	8	19
Dusky Flycatcher	8	0
Veery	8	3
Warbling Vireo	8	0
Lazuli Bunting	7	0
Eastern Kingbird	6	1
Savannah Sparrow	6	0
Swainson’s Thrush	6	0
Black-headed Grosbeak	5	0
Virginia Rail	5	2
Western Tanager	5	0
Black-chinned Hummingbird	4	0
Red-shafted Flicker	4	1
Belted Kingfisher	3	2
Chipping Sparrow	3	0
Downy Woodpecker	3	0
House Finch	3	1
House Wren	3	0
American Robin	2	0
Brown-headed Cowbird	2	1
Bullock’s Oriole	2	0
Cooper’s Hawk	2	0
Fox Sparrow	2	3
Lark Sparrow	2	0
Least Flycatcher	2	0
Pacific Wren	2	0
Pacific-slope Flycatcher	2	0
Red-breasted Nuthatch	2	0
American Tree Sparrow	1	0
Calliope Hummingbird	1	0
Cassin’s Vireo	1	0
Golden-crowned Kinglet	1	0
Gray Flycatcher	1	0
Hammond’s Flycatcher	1	0
Mountain Chickadee	1	0
Northern Saw-whet Owl	1	0
Rose-breasted Grosbeak	1	0
Red-eyed Vireo	1	0
Sharp-shinned Hawk	1	0
Swamp Sparrow	1	0
Steller’s Jay	0	1
Total	2121	494
Species	63	33

2020, Week 11: A Climactic End!

October 18, 2020

by Matthias Bieber

Our final week (Oct 10-15th) was an eventful one because of both weather and interesting birds! We banded only 57 birds of 10 species which is below average for Week 11 which is only 6 days, and we missed two days to poor weather which made the week even shorter. Considering we could only band on 4 days this week, the daily average of 14.3 birds is actually well above the Week 11 average of 10 birds/day. In fact, our Wednesday total of 29 birds, thanks to good mid-morning activity of mixed flocks, is the highest single day total ever recorded during the final week at VLBO. High winds kept us from opening on Saturday and a combination of wind and rain again kept us closed on Tuesday. Fall truly set in this week with cold nights and much cooler daytime temperatures.

Wet weather prevented us from opening on Saturday

Fittingly, the most exciting birds of the week came on the last day of the season. The morning started with our 2^nd Pacific Wren of the year which are always a treat to band. Soon after we noticed a Steller’s Jay fly across the marsh to the willows around net 19 and sure enough, not long after, it hit our nets and we were lucky enough to get our hands on it before it escaped. Steller’s Jays are hard to catch in our songbird mist nets due to their size and intelligence; only 4 have been banded at VLBO in the past. We were thus very surprised to see this bird was actually a recap – we assumed it would be the individual banded here last year but turns out it was actually banded in 2014! That more than likely makes this bird our oldest recap of the season.

After our captures started to peter out for the day, we found an American Tree Sparrow in our nets during closing. A relatively uncommon winter migrant that normally arrives just as we are finishing up our season means we’ve never banded this species before. That makes the final bird of the season a new species for the station! A final highlight came as we were taking down the nets and Anna spotted a bobcat on the net trail just a few metres from her! Luckily I also caught a glimpse as it scurried off through the roses. This is the first bobcat we’ve ever encountered at the station – what a nice surprise to finish off with!

Audubon’s Warbler once again headed the list of most banded species this week with 16, followed by Ruby-crowned Kinglet (9), Song Sparrow (8) and Oregon Junco (7). Yellow-rumped Warblers average only 2 for Week 11 and we banded 20 in total, showing that their migration is extended quite late this year. Ruby-crowned Kinglets were slightly above average while the other species in the top 4 were below average. Marsh Wren continued their strong year with 6 more this week, twice the average, while Lincoln’s Sparrow dropped off with only 2 banded this week which is well below average. Species diversity was low as we missed a few of the more likely late season species this week, including Common Yellowthroat, White-crowned Sparrow, Sharp-shinned Hawk and Swamp Sparrow.

Stay tuned for a season summary coming soon!

Week 11 Totals
Species	Banded
‘Audubon’s’ Warbler	16
Ruby-crowned Kinglet	9
Song Sparrow	8
‘Oregon’ Junco	7
Marsh Wren	6
Unidentified Yellow-rumped Warbler	3
Black-capped Chickadee	2
Lincoln’s Sparrow	2
American Tree Sparrow	1
Downy Woodpecker	1
‘Myrtle’ Warbler	1
Pacific Wren	1
Grand Total	57

2020, Week 10: Late season action

October 10, 2020

by Matthias Bieber

In an atypical Week 11 (Oct 3 to 9) with surprising highs and lows, we banded 127 birds of 17 species. This total is well above the average of 97 and makes it the fourth most productive Week 11 we’ve had at VLBO. Recaptures were low this week with only 21 birds recaptured of 11 species but a highlight was the return of two Belted Kingfishers that we banded a few weeks ago. The week started with banding totals consistently in the teens, but dropped down to 7 on Thursday, our slowest day of the season, with primarily sparrows hitting the nets. Friday started in similar fashion with only 9 birds banded by 11 am on a consistently gloomy morning. Then, out of the blue on the penultimate net run, a mixed flock of warblers, kinglets and chickadees hit net 5, followed by more in net 7 on the final run. We finished the day with 30 birds, the busiest day of the week. Fall weather arrived this week but not before several more beautiful, warm, and unseasonably summer-like days for October, before cooling on Thursday.

The most exciting bird of the week was a Golden-crowned Kinglet, our 1^st of the season and a species not commonly banded at VLBO. Though often mixing with Ruby-crowned Kinglets in higher elevations, they rarely venture into riparian habitat in the bottom of the valley. In fact it’s only the 15^th ever banded at VLBO. We also banded a 2^nd Fox Sparrow of the season and recaptured it two days later, another Virginia Rail (our 5^th) and our 3rd of both Downy Woodpecker and House Finch.

Song Sparrow had all but locked down the top spot with a solid showing this week, until the last hour on Friday when flocks of Yellow-rumped Warblers (mostly Audubon’s but also some Myrtles and Intergrades) hit our nets. Audubon’s Warbler ended up snapping up the top spot with 29 banded, just one ahead of Song Sparrow with 28. Lincoln’s Sparrow numbers started to drop this week with only 18 banded in third place, followed by Ruby-crowned Kinglet with 17. The top three species were all at least twice the average for Week 10 and most other species were also around average or well above, with the exception of Oregon Junco.

With only 6 days left we’re currently sitting at 2064 banded of 62 species and 471 recaptures of 31 species.

Clear blue skies graced us for most of the week.

Week 10 Totals
Species	Banded
‘Audubon’s’ Warbler	29
Song Sparrow	28
Lincoln’s Sparrow	18
Ruby-crowned Kinglet	17
American Goldfinch	5
Marsh Wren	5
‘Myrtle’ Warbler	5
Unidentified Yellow-rumped Warbler	4
Orange-crowned Warbler	3
Oregon Junco	3
Common Yellowthroat	2
Black-capped Chickadee	1
Downy Warbler	1
Fox Sparrow	1
Golden-crowned Kinglet	1
White-crowned Sparrow	1
House Finch	1
Spotted Towhee	1
Virginia Rail	1
Grand Total	127

2020, Week 9: A saw-whet surprise!

October 3, 2020

by Matthias Bieber

During Week 9 (Sept. 26 to Oct. 2) of our fall migration monitoring program, we banded 181 birds of 20 species. This total is above the long-term average of 146 for the week, which shows that bird activity is not winding down quite yet and suggests that migration is drawn out over a longer period this year, rather than the usual peak we see during weeks 7 and 8. We also recaptured 42 birds of 10 species. The week started well with 30 to 40 new birds during the first three days before numbers dropped into to the 20s. The low came on Thursday with only 10 birds, one of the slowest days of the season. Average daily banding totals typically drop into the teens for most days in October so we will see if this late stream of migrants continues or finally dries up. After smoke and wind made for two challenging weeks of weather, Week 9 was very agreeable with mild, sunny fall days for most of it. Albeit, most mornings were cold with temps below 5°C finally causing the water birch and alder leaves to drop.

The big surprise of the week was an exceedingly cute one which awaited us in net 20 on our first net run on Sunday – a saw-whet! Northern Saw-whet owls move through the area in low numbers during the fall and in past seasons we would band owls at night. Unfortunately we are not able to run our owl banding program this year so it is fitting that one paid us a visit during the early morning hours! This is the first saw-whet we’ve caught during our regular morning banding. The other main highlight of the week was our first Hammond’s Flycatcher of the season. We typically catch one or two each year. We finally added Dark-eyed Junco to our species banded list this week with one ‘Oregon’ banded, a relatively late first record. A late House Wren was another nice surprise this week, while our 8^th Bewick’s Wren represents a new station record for that elusive species!

Lincoln’s Sparrow remained the most banded species for the fourth of the past five weeks and this week they passed Yellow Warbler as the top species of the season, ending the week with 210 banded. Song Sparrows were notably abundant this week as they moved into second place with 30 banded. Orange-crowned Warbler maintained a decent showing with 28 banded, followed by Ruby-crowned Kinglet with 24, their biggest week so far. The top four species were all well above average for a change. Wilson’s Warbler continued their poor showing with only 3 banded, though now an average number, while Yellow-rumped Warbler and Dark-eyed Junco were below average for Week 9.

September concluded with very mediocre numbers – 754 banded, just below the long-term average of 771, and the lowest number since 2014. The 41 species banded this month was slightly above average however. The busiest day of September was the 8^th with 58 birds banded, the only day over 50 for the entire month; a far cry from the hundred bird days we had during peak migration last year.

We’ve had warm, sunny days all week in the South Okanagan.

Week 9 Totals
Species	Banded
Lincoln’s Sparrow	43
Song Sparrow	30
Orange-crowned Warbler	28
Ruby-crowned Kinglet	24
‘Audubon’s’ Warbler	16
Common Yellowthroat	10
Marsh Wren	6
White-crowned Sparrow	5
Spotted Towhee	3
Wilson’s Warbler	3
Cedar Waxwing	2
‘Myrtle’ Warbler	2
American Goldfinch	1
Black-capped Chickadee	1
Bewick’s Wren	1
Hammond’s Flycatcher	1
House Wren	1
Northern Saw-whet Owl	1
‘Oregon’ Junco	1
‘Red-shafted’ Flicker	1
Savannah Sparrow	1
Total	181

2020, Week 8: Autumn brings wind

September 26, 2020

by Matthias Bieber

We eagerly hoped for a flux of migrants this week in the wake of the passing smoke on Saturday. This was not really the case with 154 birds banded of 19 species banded during Week 8 (Sept 19-15), which is less than last week and below the long-term average of 200 for this week. We also recaptured 36 birds of 10 species. After the weekend we did see signs of increased migrant activity but our banding operations were interrupted by strong early morning southerly winds on Wednesday and again Friday. We could only open the nets briefly both days and only caught a few birds. Sustained winds over Wednesday night caused the demise of our banding tent and knocked down a few small trees. Thursday was the busiest day of the week with 45 birds banded. Accounting for the mist net hours lost to wind produces a capture rate 0.35 birds per net hour this week, which is actually just above the station average capture rate of 0.34 for Week 8, assuming full net hours are normally attained.

In the short time we opened on those days we did manage to catch some good birds however! Wednesday morning produced our third Belted Kingfisher of the season – another juvenile – and the first of only 3 birds on Thursday turned out to be our first Pacific Wren of the year! We don’t typically catch many of this species so they are always a treat to encounter. Our other new species of the season this week was a Swamp Sparrow, another uncommon late migrant that is becoming more regular this time of year. We also banded our second Red-breasted Nuthatch of the season.

Lincoln’s Sparrow reclaimed the top spot this week and stayed their above average course with 38 banded. Orange-crowned Warbler moved up to second with 32 which is still quite below the average of 52 for Week 8. Common Yellowthroat and Song Sparrow were 3^rd and 4^th this week with 18 and 17 banded, respectively. These were both close to average for the week. Audubon’s Warbler were fewer than last week with only 11 banded, and we finally got another Myrtle Warbler which have been few and far between. Ruby-crowned Kinglets are slowly increasing in number but they remained below average this week, as did White-crowned Sparrow, and Wilson’s Warbler with only 1 banded. Marsh Wren and Spotted Towhee were above average. Gray Catbirds held on with 2 more banded this week and the familiar but somewhat forgotten faces of two Cedar Waxwings were a nice surprise one morning. Waxwings closed in slightly on Yellow Warbler for the top spot of the season, now at 186, while Gray Catbird is a close third with 183. Still some ways behind but quickly leaping up the ranks are Lincoln’s Sparrow, now with 167.

One of several Common Garter Snakes around the station

Census produced some other nice highlights this week, including a White-throated Sparrow and 4 American White Pelicans.

Thanks to our volunteer Lakesha Smith for helping us out these past two weeks! Lakehsa is an aspiring young biologist who has banded at Long Point Bird Observatory and the Boreal MAPS program in northern Alberta. Her enthusiasm and optimism lit up our days even during the gloomier weather this week.

Species	Banded
Lincoln’s Sparrow	38
Orange-crowned Warbler	32
Common Yellowthroat	18
Song Sparrow	17
‘Audubon’s’ Warbler	11
Ruby-crowned Kinglet	9
Marsh Wren	6
Spotted Towhee	6
Cedar Waxwing	2
Gray Catbird	2
White-crowned Sparrow	2
Savannah Sparrow	2
American Robin	1
Black-capped Chickadee	1
Belted Kingfisher	1
‘Myrtle’ Warbler	1
Pacific Wren	1
Red-breasted Nuthatch	1
Swamp Sparrow	1
Unidentified Yellow-rumped Warbler	1
Wilson’s Warbler	1
Total	154

2020, Week 7: Up in Smoke

September 20, 2020

by Matthias Bieber

This year, migration did not peak during Week 7 (September 12-18^th) as is typical of our fall migration monitoring program. In fact, it was actually less productive than last week with 190 birds banded of 23 species, which is below the station average of 217 for this week. Daily numbers were pretty consistent overall; the slowest day came on Tuesday with 11 birds banded and the busiest on Thursday with 47, thanks to an influx of Audubon’s Warblers, while the rest of the days ranged between 22 and 36 birds. Recapture rates were relatively low with only 34 birds recaptured of 13 species, an average of 4.9 per day. Thick smoke from the fires south of the border rolled in Saturday afternoon and persisted through the rest of the week, blocking out the sun and muting the weather in general. The smoke was so dense on Monday and Tuesday that we could barely see the bluffs opposite the marsh and consequently we curtailed our mist netting effort somewhat.

Banders Matthias and Anna with two Belted Kingfishers

The most exciting moment of the week came with the capture of one of our most anticipated species – not one but TWO Belted Kingfishers! We record kingfishers almost daily but none had found their way into our nets until now, when these two juvenile females, likely distracted by their squabbling, hit net 9. This was also the only new species for the season this week. Another interesting bird was a very late Northern Waterthrush which also happened to be the largest waterthrush we’ve caught this season at a whopping 19.9 grams. We also banded our 4^th Virginia Rail of the season as well as our 11^th and 12^th Yellow-breasted Chat – 12 is a new season record for the species, beating the previous record set last year! We also passed the milestone of 1500 birds banded this week.

The top 4 species were shuffled a bit this week with ‘Audubon’s’ Warbler taking the top spot with 43 banded and Lincoln’s Sparrow dropping to second with 40. Orange-crowned Warbler (30) and Common Yellowthroat (23) were 3^rd and 4^th respectively. In stark contrast to the top two species which were well above average in number, Orange-crowned Warbler numbers were 50% of the average for Week 7 and a far cry from their seemingly endless stream this time during the last two years. Wilson’s Warblers also continued to be far below average as did Song Sparrows. Common Yellowthroat, Ruby-crowned Kinglet, and Marsh Wren were about average for the week. Gray Catbird are quickly winding down and Yellow Warblers were completely absent this week, signifying they likely end of their departure from our area.

The smoke may be a factor in the low numbers of migrants passing through this week. However, interestingly, numbers of some species (as mentioned above) were actually typical or above average, and there was a noticeable increase in waterfowl and swallow activity in the area. Large flocks of Barn and Violet-screen Swallows (several hundred all told) foraged over the Okanagan River throughout the morning every day during the second half of the week.

Many of you are probably wondering about the effects of this smoke on bird physiology. You may have seen the news articles about the mass die offs of migrating songbirds, particularly insectivores, in New Mexico which may have something to do with the fires but the causes are yet unclear. Air pollution in general has been shown to be detrimental to birds in many ways including causing respiratory stress, immunosuppression, increased stress levels and detoxification effort, behavioural changes and reproductive impairment. (Sanderfoot and Holloway, 2017). A range of pollutants including carbon monoxide, ozone, sulphur dioxide, smoke, heavy metals and urban and industrial emissions were found to be attributed to these adverse impacts. But the effects of smoke on individual species is mostly still unknown, and the composition of smoke changes as it travels long distances. We don’t really know exactly how the smoke in our area is impacting these migrants. Monitoring bird health and watching for signs of stress is one of the most important duties for banders and we have been extra vigilant during this week. So far we have not observed signs of abnormal stress in the birds we handled this week.

Last year and other recent years, migration peaked during Week 8 so things could still pick up. Let’s hope Orange-crowneds and Wilson’s rebound next week!

Species	Banded
‘Audubon’s’ Warbler	43
Lincoln’s Sparrow	40
Orange-crowned Warbler	30
Common Yellowthroat	23
Song Sparrow	14
Ruby-crowned Kinglet	7
White-crowned Sparrow	5
Wilson’s Warbler	4
Marsh Wren	3
Belted Kingfisher	2
Dusky Flycatcher	2
Gray Catbird	2
Pine Siskin	2
Red-shafted Flicker	2
Spotted Towhee	2
Yellow-breasted Chat	2
House Finch	1
Nashville Warbler	1
Northern Waterthrush	1
Savannah Sparrow	1
Virginia Rail	1
Warbling Vireo	1
Willow Flycatcher	1
Total	190

References:

Olivia V. Sanderfoot and Tracey Holloway. 2017. Environmental Research Letters. 12, 083002

2020, Week 6: Lincoln’s Sparrows, Yellowthroats, and Yellow-rumps

September 13, 2020

by Matthias Bieber

Migration picked up this week with a significant increase in the number of birds banded – 207 of 25 species. This is well above the Week 6 average of 168 birds. The week started out relatively slow but a windy Monday, which prevented us from opening, and a cold subsequent night brought new waves of migrants to the station. We banded 58 birds on Tuesday which is the busiest day we’ve had in some time, and 49 on Wednesday. Banding totals were in the 20s for the rest of the week. We also recaptured 48 birds of 11 species including a Veery and Audubon’s Warbler that were banded in 2019.

The result of a busy late net run Tuesday!

The biggest highlight of the week was probably a Mountain Chickadee that found its way into net 7. This is only the 9^th banding record for VLBO since the species is rarely found in riparian valley bottom habitat. We finally banded our first Ruby-crowned Kinglets of the season this week as well as our first Savannah Sparrows and ‘Myrtle’ Yellow-rumped Warbler. Two more Virginia Rails, two Yellow-breasted Chats, our 2^nd House Wren and a Western Tanager (only our 6^th) were also highlights. Another very cool bird encountered this week was a leucistic Lincoln’s Sparrow with a mostly white head and several white wing feathers! Leucism refers to various conditions in animals that result in a partial lack of pigmentation, particularly in the feathers of birds. It most often manifests as a few individual white feathers and we don’t often see it as extensive as in this bird!

We had several non-avian wildlife highlights this week! Beavers felled a small tree and have been busy clearing understory in a small area near net 4 and a bear was observed briefly on morning. We’ve continued to count many snakes in our net lanes, including a gopher snake that crawled right into our banding tent! As well, white-tailed deer have been spending time at the station and unfortunately ripped a few of our nets. Since it has been relatively slow we’ve been working on repairing these holes in between net runs.

Lincoln’s Sparrow was once again the most banded species with 44, followed closely by Common Yellowthroat (38) and Audubon’s Warbler (37), and Orange-crowned Warbler (17) rounded out the top four. The top three species were all well above average for Week 6, especially Audubon’s Warbler, whereas Orange-crowned Warbler was again far below the average of 41. Wilson’s Warblers still haven’t shown up in good numbers with only 1 banded this week and Song Sparrows were also below average. Yellow Warbler and Willow Flycatcher hung on for another week; in fact we had 6 Willows which is far above average for this late in the season. Gray Catbird, Marsh Wren, and Spotted were other common species banded in above average numbers this week. Migration should really kick up to another gear next week as we enter the peak migration period for our station!

Species	Banded
Lincoln’s Sparrow	44
Common Yellowthroat	38
‘Audubon’s’ Warbler	37
Orange-crowned Warbler	17
Gray Catbird	12
Song Sparrow	8
Marsh Wren	6
Willow Flycatcher	6
White-crowned Sparrow	5
Spotted Towhee	5
Black-capped Chickadee	3
‘Unidentified’ Yellow-rumped Warbler	3
Yellow Warbler	3
Pine Siskin	2
Ruby-crowned Kinglet	2
Savannah Sparrow	2
Virginia Rail	2
Warbling Vireo	2
Yellow-breasted Chat	2
Cedar Waxwing	1
Dusky Flycatcher	1
House Wren	1
MacGillivray’s Warbler	1
Mountain Chickadee	1
‘Myrtle’ Warbler	1
Western Tanager	1
Wilson’s Warbler	1
Total	207

2020, Week 5: The lull continues and August in summary

September 6, 2020

by Matthias Bieber

Another week has come and gone and the lull we experienced last week continued all through Week 5 with no real signs of subsiding. During Week 5 (August 29 – Sept 4) we banded only 110 birds of 23 species and recaptured 33 birds of 10 species. That total makes this the slowest week of the season so far and is below the station average of 130 birds for Week 5. The quietest day of the season came on Saturday with only 6 birds banded and 2 recaps. Things picked up a bit on Sunday with 34 banded, which had us feeling optimistic, but numbers dropped well below that for the rest of the week. The clear skies and hot weather we’ve experienced through most of August is continuing well into September. Temperatures at the station after net closing averaged 24.1°C during August and skies were without cloud over half of the days this month. This week, early mornings have been mild with temperatures rising into the mid-20s by the time we close our nets just before noon. Uncharacteristically gusty conditions during several late mornings plagued our nets this week.

Despite the lull in activity we had several exciting highlights this week: our 2^nd Cooper’s Hawk – this one a juvenile male, a Virginia Rail (also a juvenile), Cassin’s Vireo, and Red-breasted Nuthatch (our first since 2015!), all three new species for the season! Other new species for the season included White-crowned Sparrow – another sure sign that fall is on its way, and House Finch. Quiet nets allowed us to appreciate these birds all the more.

Even though the last two weeks have been unusually slow, August 2020 was actually still the second most productive August in VLBO’s 20 year history! We banded 1156 of 51 species during the month which is only beaten by last year’s record breaking season, and considering that 4 of our nets couldn’t be opened during the first 2 weeks, this total could have been higher still. The species total is the 3^rd highest ever for August. These numbers really show what a busy start we had this year, and the dichotomy in productivity from the first half of the month to the second demonstrates how unpredictable migration can be!

Number of birds banded per day in August

Lincoln’s Sparrow shot up to first place in the top species list, comprising almost a third of all birds this week with 34 banded. This is the only species considerably above the average (15.5) for Week 5. Gray Catbird (16), Orange-crowned Warbler (14), and Common Yellowthroat (11) round out the top 4; these three were all slightly below average in number. Marsh Wren is the only other common species with above average numbers this week, and Yellow Warbler and Willow Flycatcher were below average. The latter two were well above average during the first two weeks and it will be interesting to see whether they have departed early this year or if there is another later wave on the way. We should have our answer after next week as Yellow Warblers and especially Willow Flycatchers are usually gone after Week 6. The low numbers of Orange-crowned Warblers and complete absence of Wilson’s Warblers this week suggests that warbler migration may be later than usual this year.

Anna working on identifying a flycatcher by measuring wing morphology

Species	Banded
Lincoln’s Sparrow	34
Gray Catbird	16
Orange-crowned Warbler	14
Common Yellowthroat	11
Song Sparrow	5
Audubon’s Warbler	4
Marsh Wren	4
Swainson’s Thrush	3
Spotted Towhee	2
Willow Flycatcher	2
Yellow Warbler	2
White-crowned Sparrow	2
Cedar Waxwing	1
Least Flycatcher	1
Pine Siskin	1
Western Tanager	1
Western Wood-Pewee	1
Dusky Flycatcher	1
Cooper’s Hawk	1
Virginia Rail	1
Cassin’s Vireo	1
House Finch	1
Red-breasted Nuthatch	1
Total	110

2020, Week 4: Migration stall and hints of fall

August 29, 2020

by Matthias Bieber

Bird activity ground to a halt this week with only 115 birds banded and 45 recaptured, which makes this one of the slowest August weeks in recent memory. Late August is typically a slow time but not quite like this; the weekly average is 132.2 birds (or 18.8 birds per day), but in the last 5 years the average is higher, at 154 (22 per day). This period signifies a break between some of the earlier migrants and mid to late season migrants which have been slow to arrive this year. By now the vast majority of local residents have also finished breeding whereas many young birds are still actively fledging in the first half of August. Indeed, a Willow Flycatcher nest at the station just fledged this week and we are still catching some very young catbirds. The stagnant hot weather and warm nights may have something to do with this year’s amplified lull in activity. Week 4 in 2017 was even slower but dense smoke from an intense fire season may have been a factor that year. Banded birds were comprised of 25 species and recaptures of 11 species.

Diversity was low this week and we only added 4 new species to our season total which now stands at 47. Two of these were quite exciting however – Gray Flycatcher – only the 14th record for VLBO (but we seem to be getting at least 1 or 2 annually), and our earliest ever Fox Sparrow! Though not unusual for us, we typically only catch this species in small numbers the latter half of the season. Another highlight was our first Downy Woodpecker, a feisty juvenile female. Perhaps the biggest highlight of the week came in mammalian form. On Sunday we were startled by a cow moose in the oxbow right behind net 4! We spotted fresh moose tracks along the net trail earlier in the morning so it wasn’t a complete surprise. Moose have been observed at VLBO in recent years as well. We also banded our 7^th Bewick’s Wren and 7^th and 8^th Yellow-breasted Chats of the season, putting us in range of the season records for those species.

Though numbers were down for most species, Gray Catbirds continued to move through in good numbers as they significantly outpaced all other species with 40 banded. This is actually well above average for week 4. Second and third this week were Yellow Warbler and Lincoln’s Sparrow, both with 11 banded. The latter is one of our abundant mid to late season migrants that was first banded on Wednesday, which is a relatively late as they usually show up in Week 3. Interestingly, Lincoln’s Sparrow immediately became one of our most common species with 4 banded on their first day and 5 the next, and actually finished the week above average. Other common fall migrants like Orange-crowned, Wilson’s, and Yellow-rumped Warblers have all been trickling by very slowly so far. We are still awaiting one of the more rare warbler migrants to show up in our nets, although a bright adult male American Redstart was spotted on census which was a nice treat! Song Sparrow, Willow Flycatcher, and Common Yellowthroat, our other station regulars, were all below average.

Hot summer weather with clear skies continued this week.

Species	Banded
Gray Catbird	40
Yellow Warbler	11
Lincoln’s Sparrow	11
Common Yellowthroat	9
Song Sparrow	7
Orange-crowned Warbler	4
Spotted Towhee	3
Warbling Vireo	3
Wilson’s Warbler	3
American Goldfinch	2
Cedar Waxwing	2
Lazuli Bunting	2
Marsh Wren	2
Nashville Warbler	2
Willow Flycatcher	2
Yellow-breasted Chat	2
Swainson’s Thrush	2
‘Audubon’s’ Warbler	1
Pine Siskin	1
Veery	1
Western Wood-Pewee	1
Bewick’s Wren	1
Gray Flycatcher	1
Fox Sparrow	1
Downy Woodpecker	1
Grand Total	115

2020, Week 3: A Summer Daze

August 22, 2020

tags: birdbanding, migration

by Matthias Bieber

This past week was hot, hot, hot (!) in the Okanagan with temperatures soaring up to 39 °C in the area! The third week of August (August 15-21) is usually pretty slow for our fall migration monitoring program and the extreme heat may have been a compounding factor. We only banded 203 birds of 24 species this week, which is still slightly above the station average of 170.8, but much less so than the previous two weeks. That’s an average of 29 birds per day with the busiest day being Tuesday with 60, and the slowest day being on Friday with only 7 new birds. That morning, intense gusts of winds picked up very suddenly and forced us to close our nets 1.5 hours early. To add to the challenging weather this week, the Mount Christie fire, which started Tuesday afternoon and blanketed the valley with smoke for the rest of the week, may also have been a factor in the decline of activity; the three subsequent days each saw under 20 birds banded. We also recaptured 57 birds of 12 species.

The top highlights this week were the season’s 1^st Sharp-shinned Hawk, 2^nd Lark Sparrow (3^rd record overall for VLBO), 1^st Calliope Hummingbird, 3 Yellow-breasted Chat and 3 Bewick’s Wren.

Cedar Waxwings continued to be very prevalent with 41 banded, Gray Catbirds are creeping up the ladder to 2^nd place with 39 this week, followed by Yellow Warbler (27), Willow Flycatcher (22), and Common Yellowthroat (19). The number of Cedar Waxwings is well above average for week 3; in previous years, numbers quickly dropped after the first two weeks. We finished the week with 180 which is actually a new season record, surpassing last year’s 156! The number of Yellow Warblers and Common Yellowthroats banded are still a bit above average and the other top species are very close to average for week 3.

Generally speaking, warbler migration was quite slow this week. Orange-crowned Warbler, Northern Waterthrush, and Wilson’s Warbler (we finally banded our first this week) were below average and we missed Nashville and MacGillivray’s Warblers altogether. Of our other regular species, Marsh Wren were above average, American Goldfinch right on average and Song Sparrow below average. We’re also still waiting for the first Lincoln’s Sparrow to show up in our nets as well as both species of rail – Virginia and Sora.

This week we were able to open two more nets as water levels continue to drop, which means we are almost operating at full capacity with 13 of our usual 14 nets open. We finished the week just shy of 1000 banded for the season, with 979 birds of 44 species and 219 recaptures of 20 species.

Species	Banded
Cedar Waxwing	41
Gray Catbird	39
Yellow Warbler	27
Willow Flycatcher	22
Common Yellowthroat	19
Song Sparrow	9
American Goldfinch	8
Marsh Wren	5
Pine Siskin	4
Orange-crowned Warbler	3
Western Wood-Pewee	3
Yellow-breasted Chat	3
Bewick’s Wren	3
Audubon’s Warbler	2
Black-headed Grosbeak	2
Eastern Kingbird	2
Northern Waterthrush	2
Veery	2
Chipping Sparrow	2
Western Tanager	1
Lark Sparrow	1
Sharp-shinned Hawk	1
Wilson’s Warbler	1
Calliope Hummingbird	1
Grand Total	203