ML619445862

Age

Not specified

Sex

Not specified

Observation details

Stocky, front-heavy, compact tern with relatively short neck, short bill, and long tail. Part of a larger flock of ~25 terns (also see photos under “tern sp.”). They could have all been arctic terns, with some others appearing to have similar body shape/proportions. The flock was first seen flying west way out on the lake, bobbing a bit in flight. They took a big u-turn and flew back east over land. The entire observation lasted about 2 to 3 minutes. The photo of the solo bird and the photo showing six terns were both taken at 2:53. The photo with ~25 terns was taken at 2:55, probably just a few seconds before the flock disappeared out of view. Arctic terns were also seen today in Etobicoke, near Col. Sam Smith Park, around the same time. Common terns are the expected smaller/medium tern species here, but not the right shape. One comparison that comes to mind is that COTEs seem to be more Luigi shaped (longer, lankier) and ARTEs more Mario (e.g., bigger in the chest). If this were soft clay, you’d have to keep rolling an ARTE to get a COTE. To my eye, the terns in the photo with six terns all show “Mario” terns, while the tails, wings, bills also look better overall for ARTE than for COTE, though some birds (especially those on the left) are impossible to assess on some of these features. The third (from right) bird appears to show a bit of translucence in its primaries as well. Unfortunately, the only other photos I have are too blurry to be useful. It would have been nice to see the color of the bills or to hear their calls. Oh well! I can see a case for reporting 1, 3, 6, or 25 ARTEs, with any others left as tern sp. I’ll note that I only have one photo of a solo tern and one photo with six terns besides the photo with all 25. So if this was a mostly COTE mixed flock but with all ARTEs in the solo and/or six-tern photo, then I got very lucky when I semi-randomly zoomed in on these particular birds. So my best guess is this was a pure, or close to pure flock. While I am only reporting one ARTE (for now), I would be receptive to any suggestion that I should report a higher number. Thanks to others (especially Garth Riley) for help with this ID! -------------------------- Update (May 23, 2024). I am revising my count from 1 ARTE to 25 ARTE. Thanks to Glenn Coady for reaching out and urging me to make this change. I agree that I was being too conservative! Some extra points in favor of a pure ARTE flock over a mixed ARTE/COTE flock: - birds all appeared to be same size, with no noticeable differences in flying style - a tight flock, flying together "with a purpose" - mixed flock would be weird given the circumstances, e.g. COTE could have a hard time keeping up with ARTE! - what are the odds that every bird I zoom in on is ARTE in a mixed flock? - would be awfully late for migrating COTEs to be passing through this area... while not yet in COTE safe dates (OBBA), GC says these dates (which he helped set) are very conservative to avoid issues with COTE feeding in different squares from where they breed - timing lines up, with large flocks (~35) observed on Ottawa River just one day earlier Apparently the first county record for ARTE, but something like the 17th GTA record. Pretty cool!

Technical information

Model

COOLPIX P1000

ISO

100

Focal length

216 mm

Flash

Flash did not fire

f-stop

f/5.6

Shutter speed

1/640 sec

Dimensions

4048 pixels x 632 pixels

Original file size

359.28 KB