Great Egret

Great Egret

Saturday, 3 January 2015

New Year's Day CBC at SCNWA

What better way to start off the new year than with a Christmas Bird Count? Which is why for the last number of years, the decision was made to hold the St. Clair NWA CBC on Jan 1. Also because at one point, waterfowl hunting ended on Dec 31, and so by holding the count in January, we would have a better chance of accessing some of the private marshes that are critical for the kind of greater numbers of birds we hoped to find.

However in the last few years, with the large population of Canada Geese persisting in the southwest, the goose hunting season has been extended into January. As a result, now we are finding some of those large private marshes not available to us as paying hunters get priority. But we persist and cover what we can.

The day began in impressive fashion, with spectacular skies to the south. I took this from the bridge at the entrance of the SCNWA.

The weather wasn't great however. We didn't have the snow and cold that we had to contend with a year ago, just a more serious cold and wind combination. With sustained wind between 30-40 km/hr and occasionally gusting to 60 km/hr in addition to the temperatures ranging from -7C to -3C, the wind chill factor was at times down to -18C. It certainly didn't encourage the smaller birds to show themselves! Seeing and hearing birds was greatly diminished under these conditions.

The abundance of waterfowl is a key component to tallying high numbers for this count. The recent cold weather actually may have helped in a way, since the very recently open marshes were now largely frozen with only a few sizable open areas available. It got the ducks more concentrated, so if one could find an open spot, the birds were all there.

Overall we got more than 15100 individuals of 22 species of waterfowl. This is far below one of the most memorable counts, when we had over 95,000 individuals of 27 waterfowl species in 2007.

As is often the case, Mallard (6476), Canada Geese (5368) and Tundra Swan (2454) led the way in terms of numbers.  Many other species of waterfowl were represented by fewer than 5 individuals, including Green-winged Teal (3), Hooded Merganser (2), Bufflehead (1), Northern Pintail (2), etc. We missed out entirely on species we usually get, such as Wood Duck and Canvasback. I'm sure they were out there, but just not in a place to be seen. We did, however, get a new high number for Northern Shoveler (61).

One waterfowl species which is not always recorded, but two groups of us saw this day, was Snow Goose. Given the large numbers of geese generally in the area, a small number are periodically observed in the autumn, but not always seen on the day of the count.

Here, a mixed flock of Snow Geese (6 snows and 9 blues) are flying with a few Canada Geese.

Canada Geese were in the air throughout the day, especially later. This was likely in response to their feeding schedule, as well as being shot at by hunters within the count circle or near by.

Other waterfowl included Common Merganser, mostly seen along the Thames River.

Although the majority of the Mallards were concentrated in the extensive wetlands, a few were elsewhere, including these three along a small creek system that was kept open by a municipal drain. Since they were in an area that isn't hunted, they were more tolerant of my presence.

Land birds were reduced in number, but there were some highlights. I found a group of 7 (with apologies to the original Group of Seven) American Robins feeding in a cluster of hawthorn trees along the river at the southern end of Bear Line. They were the only ones recorded for the count.

While I was pishing for other birds to see what would respond, this White-breasted Nuthatch appeared, one of only five of the species that was recorded on the day.

There were many other land bird species seen including Brown Creeper, Marsh Wren, Hairy Woodpecker, Northern Flicker, Red-breasted Nuthatch, Field Sparrow, Fox Sparrow, Hermit Thrush, White-throated Sparrow, and others but I didn't see them so I don't have any photos to show.

Our total for the day was a respectable 80 species, which matches the average of the previous decade, but well below our record high of 92. A little less wind, a bit more access to some of the best locations would, I'm sure, have made a difference.

We had record high totals of Northern Shoveler, as mentioned previously, as well as Wild Turkey (19) and Snowy Owl. Snowies have been present in impressive numbers again this year, all across southern Ontario. We tallied 15 birds, well above our previous high of 9. And I'm sure there were others. However the windy conditions resulted in them sitting on the ground rather than up on poles or buildings, and when hunkered down in the corn stubble they are much more difficult to see. The photo below was taken several days ago.

We sometimes get an impressive number and diversity of blackbird types. Not so this year, with only small numbers of Common Grackle and Red-winged Blackbird being observed. We missed out on both Rusty and Brewer's Blackbirds, both of which we get at least half the time. There were a couple of good sized flocks of Brown-headed Cowbirds, including the one in the next photo which shows a small part of the ~1900 birds in the group.

A much larger black bird species in both size and number was American Crow.

Yes we had crows, and lots of them as usual.

Although the count is officially called the St. Clair National Wildlife Area CBC, and was established by staff of the Canadian Wildlife Service who managed this NWA, it was centred on the NWA headquarters. As a result the Chatham crow roost was not originally included, but a large part of Lake St. Clair was, most of which was beyond the view from land. We shifted it a bit several years ago....we weren't giving up much value of the lake, since we couldn't see that much of it......and this crow roost phenomenon is too close by and intriguing to ignore. I discussed some of the reasons for this huge concentration of crows in Chatham-Kent in a blog post a few weeks ago. I also wrote an article for OFO News a few issues ago.

It really is challenging to get an accurate number of crows. Estimates by some experts a bit earlier in the season have been 250,000 or higher. Our highest official number for this CBC is 159,860, certainly an estimate but the best one we could get under the circumstances.

The crows come in from all directions towards the end of the day, in stages, alighting on buildings, in trees, on machinery, on gravel piles and on the ground. And then they start to head into the actual roost.

The above image shows 'a few' of them departing from one of their staging points to head towards the roost. At times, they were streaming by at a rate of up to 5000 per minute, and this would go on for some time and not include the birds already present in the roost. From the time the first birds arrive at the roost until the last birds arrive usually takes at least an hour. These next two images were taken a few years ago, well after dark, showing some of the birds in their roost along the river. On this occasion the birds were even roosting on the snow covered river!

If left undisturbed, this roost will extend for at least a kilometre along the river, with the birds occupying trees on both sides of the river.

It is an experience to see them depart from the roost just before daybreak. One can count thousands of birds leaving part of the roost, but the trees don't look any less congested with the remaining crows.

Our total number of crows for this year's count will go in at 134,000 birds. It is an estimate, to be sure. But in my opinion it is a conservative estimate.

Happy New Year everyone!

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