Rocky Point Bird Observatory: Week 3: We Owl Screeched For Joy

Week three of migration has come to a close with 184 new birds banded at Rocky Point and 122 at Pedder Bay. The gloomy weather this week kept the birds at bay, putting us about 25% behind the week three average for Pedder Bay and about 20% behind for Rocky Point. But fear not, we're all looking forward to the big pushes of migration in the weeks to come. One of our earlier migrants, Western Flycatchers, stole the show at Rocky Point with 38 individuals banded. White-crowned Sparrows and American Goldfinches followed closely behind with 28 and 23 individuals banded, respectively. Pedder Bay didn't see quite the same push of migrants this week, with 10 Wilson's Warblers taking the top spot, followed by 9 Purple Finches while Bushtits, Western Flycatchers, Swainson's Thrushes and Spotted Towhees ended the week with 8 individuals each.

We banded the 500th bird of the season for both stations this week, ending the week with 599 birds for the season at Rocky Point and 517 at Pedder Bay. This year, the 500th bird was a Western Flycatcher for both stations! Any guesses for #1000?

Observations around the stations have been interesting as always, with Roosevelt Elk greeting us in the front field of Rocky a few times this week, and Black Bears seen at both stations. The Big Backyard Bioblitz was this weekend and the banders spend much of their downtime observing the biodiversity around the stations. One of which was the Locust Sawfly, a first observation for western Canada!

A Locust Sawfly photographed by David Bell.

A Roosevelt Elk at Rocky Point photographed by James Kennerley.

One of our earliest migrants, the Rufous Hummingbird, has mostly passed through at this point in the season, but we're still catching the occasional Anna's Hummingbird. This young male is just starting to grow in its brilliant gorget feathers. Next year, this individual will have a full throat and head covered in bright pinks and purples.

A young male Anna's Hummingbird photographed by James Kennerley.

We had no season's first for banding this week, but both Purple Finches and Western Tanagers are having a good season so far, and this week was no exception. We banded our second Cassin's Vireo of the season, this time an after hatch year individual. Note the more defined "spectacles" than the hatch year bird banded last week that you can see in the previous blog post.

An after hatch year Cassin's Vireo photographed by Emma Radziul.

However, the star of the show this week was far and away a bird banded by Emma on August 7th. A first record for the migration program at Rocky Point Bird Observatory, and the inspiration for this week's blog title... A Western Screech-Owl! This individual is very young, still mostly in its very fluffy juvenile plumage. This elusive species is hard to come by on Vancouver Island, and even Rocky Point's owl banding program has only one banding record of the species, so you can imagine the surprise when we found this one in the net just after sunrise!

A Juvenile Western Screech Owl photographed by Emma Radziul.

We had a couple of older recaps this week, including this pair of Spotted Towhees caught at Pedder Bay on August 10th. Recapturing birds year after year provides us with valuable data on the survivor rate and life-span of these species. These two were banded in 2019 and 2020, both as hatch year birds. Can you tell which is which?

Two adult Spotted Towhees photographed by David Bell

Trick question! We can't tell which is which just from these photos either. However, these photos show a great example of what moult looks like in the flight feathers of birds. In the first image, the Spotted Towhee is just starting to grow in some new feathers in the centre of the wing. In the second image, we can see this bird has replaced a couple of feathers in the centre of the wing (the darker feathers) that contrast heavily with the worn, browner feathers. This is called a moult limit. Birds generally replace their flight feathers once a year, so since we can see two generations of feathers in the wing we know these birds are at least 2 years old. In a lot of cases, thats the best we can do, which is why you often see us refer to birds as "after hatch year". Without banding, we would never be able to know exactly how old these birds are!

It's always nice to get multiple ages of a species on the same net round, as it makes it much easier to see the differences! Here we have a hatch year (left) and after hatch year (right) bushtit!