Vireos And Warblers Of Late November

On Thursday, November 20 fellow birder Blake Mann discovered a Warbling Vireo while he was birding along the Marsh Trail at Rondeau Provincial Park. If he had found this bird a few months earlier then it would not have caused a stir, but November 20th is a very late date for a Warbling Vireo to be present in the Great Lakes region. I believe that there are only a couple of later records for Ontario. Unfortunately, the vireo vanished before Blake could study it in detail and his photos were not in focus due to the brevity of the encounter.  

However, this Warbling Vireo caught the attention of some members of the birding community for another reason. Earlier this year, the Clement's Bird Checklist (which curates the taxonomy for eBird) accepted the split of Warbling Vireo into two species - Western and Eastern. While Ontario has no official record of Western Warbling Vireo it is a species that should be looked for, as there are several valid records from the east coast of the United States, usually late in the fall or early in the winter. Given the time of year, a Western Warbling Vireo would be a distinct possibility for the Rondeau bird. 

Jude Szabo, a friend of mine who is a fellow resident of Hamilton, was curious if I was interested in looking for the vireo the next day. Jude is in the midst of an Ontario big year and so this was an opportunity he didn't want to pass up in case the vireo was proven to be a Western Warbling Vireo. I had spent the week stuck inside working on my computer and was looking forward to a day of birding so I quickly confirmed my availability. And so before dawn the next morning, we were speeding west down the 401. 

In reality, I did not expect to re-find the vireo given how big Rondeau Provincial Park is, and indeed, after a two hour search along the beginning stretch of the Marsh Trail, we had seen no vireo. The birding was good though, with many ducks and Tundra Swans on the open bay, a flyover Purple Finch, and a nice collection of passerines and other smaller birds including a late Yellow-bellied Sapsucker and Ruby-crowned Kinglet. We decided to stretch our legs and continue walking down the Marsh Trail to see what else we could turn up. A dark morph Rough-legged Hawk hovered and hunted over the marsh. This is one of my favourite raptor species and I enjoyed watching it, even though it was rather distant. 

Rough-legged Hawk - Rondeau Provincial Park, Chatham-Kent

Though there was a brisk west wind, the sun came out and the temperatures were reasonable for late in November. And there were a lot of birds to keep us occupied. Flocks of American Tree Sparrows filled the shrubbery while Swamp Sparrows chipped from within the dense stands of cattails. At one point, a Nelson's Sparrow perched up right beside the path, providing excellent (though brief) views. Nelson's Sparrows pass through in small numbers each autumn but they have usually vacated the province by late October. Unfortunately it flushed before Jude was able to see it, but on our return walk a few hours later Jude was able to observe it at the same location.  It will be worth seeing if this bird sticks it out until December as there are only a couple of prior December records in Ontario. 

We reached the very southern part of the Marsh Trail and hoped that we could check the beach for shorebirds, but a muddy channel thwarted our plans. However, we spotted a couple of sandpipers in the pond just east of here - a Greater Yellowlegs and Long-billed Dowitcher. 

Greater Yellowlegs - Rondeau Provincial Park, Chatham-Kent

Considering the mild weather of the last few weeks, these birds were not a total surprise as Greater Yellowlegs in particular can hang around until freeze-up and sometimes one will stay into December. The Long-billed Dowitcher was quite late though. A check of eBird shows just one December record for the province, so I would imagine birders will be out here on December 1 to see if the Long-billed Dowitcher is still hanging around. 

Long-billed Dowitcher - Rondeau Provincial Park, Chatham-Kent

Jude and I made the long walk back up the Marsh Trail, retracing our steps and re-counting the American Tree Sparrows and Swamp Sparrows. We reached a point 800 m south of the location where Blake had found the Warbling Vireo when we discovered a small flock of songbirds. We used a scolding call to attract the birds - Black-capped Chickadees, Golden-crowned Kinglets, Downy and Red-bellied Woodpeckers, Carolina Wrens, even a Winter Wren. Suddenly Jude announced "I have the vireo!". I looked just in time to see a small songbird drop deeper into the foliage and disappear. It was a tense few minutes as we waited to see it again. Suddenly a flash of white and yellow caught my eye. Expecting it to be the Warbling Vireo, I was shocked to see it was a White-eyed Vireo!

White-eyed Vireo - Rondeau Provincial Park, Chatham-Kent

Though White-eyed Vireos arrive in southwestern Ontario each spring, they are a rare fall bird (indeed, this was my very first fall White-eyed Vireo for the province). However, Ontario has seen a spate of White-eyed Vireo records over the past month, so it wasn't completely surprising. The White-eyed Vireo hung around for a few minutes, allowing Jude and I to take some nice photos of it. 

White-eyed Vireo - Rondeau Provincial Park, Chatham-Kent

Jude was second-guessing his quick identification of the Warbling Vireo from a few minutes earlier, now that this White-eyed Vireo had entered the fray. He was questioning how he could have mistaken these two very different species. Luckily, those fears were put to rest as I noticed the Warbling Vireo flitting over the path just a couple of minutes later. He had made the right call initially - the "two bird theory" was accurate. 

Eastern Warbling Vireo - Rondeau Provincial Park, Chatham-Kent

We made sure to document the Warbling Vireo with good photos since it can be very difficult to differentiate Eastern vs Western Warbling Vireo (even with good photos). Luckily, this was a relatively straightforward ID. I sent the photo off to some friends, and we also posted the photos to the Ontario Birds Discord server later that day. The consensus was that it is an Eastern Warbling Vireo. 

Eastern Warbling Vireo - Rondeau Provincial Park, Chatham-Kent

One key field mark is bill size, and this one has a relatively large bill that is typical for Eastern Warbling Vireo. This bird is also relatively drab with a plain crown, while Western Warbling Vireo often has a darker crown which, when combined with a smaller bill, gives an appearance somewhat like a Philadelphia Vireo. Some details of the wing moult also point to this being an Eastern Warbling Vireo. 

Eastern Warbling Vireo - Rondeau Provincial Park, Chatham-Kent

We were still pretty pleased that we had re-found the bird and helped put the question of its identification to rest. I'm sure it would have bugged Blake for a long time if the bird was never found again, given the potential of it being a first provincial record.

Eastern Warbling Vireo - Rondeau Provincial Park, Chatham-Kent

With still a few hours of daylight remaining, Jude and I dropped in at Keith McLean Conservation Area followed by a visit to the Blenheim lagoons. 

White-crowned Sparrow - Keith McLean CA, Chatham-Kent

A Western Cattle-Egret had been spending a few days at Keith McLean, picking grasshoppers off one of the dykes, and it was still working away when we arrived. This is a scarce spring and fall migrant in Ontario, but southwestern Ontario is good for a record or two each November. This one was originally found by Jacquie Montgomery on November 16. 

Western Cattle-Egret - Keith McLean CA, Chatham-Kent

Western Cattle-Egret - Keith McLean CA, Chatham-Kent

Our visit to Blenheim was relatively uneventful. Most interesting to me was a Snapping Turtle periscoping from one of the ponds. I can't recall ever seeing one active this late in the year before. 

Snapping Turtle (Chelydra serpentina) - Blenheim Lagoons, Chatham-Kent

Before finishing this blog post, I wanted to highlight one other rare bird that has appeared in the province. Yesterday morning (November 24), birders David Reid and Taya Kehler discovered a Townsend's Warbler at Lakeside Park in Mississauga and quickly got the word out to the birding community. This is a western species that is somewhat related to the Black-throated Green Warbler, which is a common migrant and breeding species in Ontario. The Townsend's, however, is quite rare. It has been documented fewer than 20 times previously in the province. Along with many others, I drove down to the Lakeside Park and after a quick 15 minute search found the Townsend's flitting around with some Black-capped Chickadees. It was difficult to see well as it was constantly moving and actively searching for insects to eat.

Townsend's Warbler - Lakeside Park, Mississauga, Peel Region

There are only two accepted records of Townsend's Warbler from the Greater Toronto area: one found at Thickson's Woods in Whitby, Durham Region in April 2000, and one banded at Tommy Thompson Park, Toronto in September 2022. There may be a couple of other records that haven't been reviewed by the Ontario Bird Records Committee. Since Lakeside Park is also located within the Hamilton Study Area (a circle with a 25 mile radius centred on Dundurn Castle, Hamilton), all of us Hamilton listers were out to see it as well. This is only the second record of Townsend's Warbler within the HSA. The only previous record was seen by just one observer in a backyard in Grismby in October 2022. 

Townsend's Warbler - Lakeside Park, Mississauga, Peel Region

I timed my visit well since the Townsend's Warbler was last seen about an hour after I observed it and many later-arriving birders missed it. It hasn't been re-found yet today, either.

It was nice to see so many fellow birders at Lakeside Park, many whom I had not seen in months. My good friend Dave Szmyr had also driven down from Barrie since he had never seen a Townsend's Warbler before. It was nice to do some birding with him and then catch up over a beer afterwards.