Tim Poole describes an incredible spectacle in the stubble fields west of Oak Lake last Friday.
Last Friday (October 27 2017), Christian Artuso and I were driving from Canupawakpa Dakota Nation on the long drive back to Winnipeg when to our collective astonishment, we came across a field full of cranes. Yes, quite literally a field!
Seeing large numbers of Sandhill Cranes is not a complete surprise – after all, the previous Saturday, Glennis Lewis and Linda Boys had encountered 1200 Sandhill Cranes on the west side of Oak Lake. I had also counted 800 on the roads north and west of Canupawakpa an hour earlier.
Initially the numbers of cranes did not appear to be anything special. As we crossed the Bellview Road on 42N our eyes were drawn to a flock of Canada and Cackling Geese with some cranes standing around in the foreground. Christian, offered me the choice of geese or cranes to count. I opted for the geese – the best decision I made all day! As Christian lifted his binoculars to begin counting what he suspected would be a few hundred birds, it suddenly dawned on him that this would not be so simple. For in the background stood a multitude of cranes.
It was the densities of cranes which took us aback. Even an experienced bird surveyor as Christian was completely gobsmacked by the scene infront. Just row upon row upon row of cranes.
Christian began counting, initially he ticked off groups where he could – 21 groups of 20, followed by 11 groups of 20, then followed by 31.5 groups of 100. At this point things got tricky as the lay of the land impeded our view. Driving to the east end of the section, we turned south and were greeted by the entire flock. Having counted up to a certain point before, Christian was able to continue. Next up 26.5 groups of 100 cranes, another 250 and then 320 mooching around in the foreground. While this was going on, I counted the flocks of birds flying in – 2, 18, 12, 66, 37, 3, 13 and more. Later that day I tallied everything and came to a figure of 7,363 Sandhill Cranes (and not a single Whooping being the sole disappointment).
My previous highest total of cranes was around 1000 spotted south of here in the Maple Lake area in late September 2016. There were also large concentrations of cranes in the Big Grass Marsh area in the 1960’s. Christian suspected that these might be Lesser Sandhill Cranes. If they were, then these cranes would breed in the Arctic tundra rather than the boreal – those birds presumably pass through earlier in the fall. Lesser Sandhill Cranes are smaller than the boreal breeding intermediate birds (the Greater Sandhill Crane, the larger variant breeds in the northern US). In any case, it was not possible to distinguish the difference given it is solely a question of size.
We tried to drive forwards at this point but the first few birds began to flush and we were not keen for these birds to waste energy in sub-zero conditions mid migration. Flushing any bird, even by accident, costs energy which is better conserved for migration. We drove back around and found our way to the south side of the mile section. Christian tried another count which only went to confirm his first total give or take a few! Interestingly, some younger birds were dancing in the foreground – these birds do after all mate for life.
Cranes do not forage in water, although they roost in shallow water and certainly breed in open wetlands surrounded by trees and shrubs. In migration these flocks will feed in grasslands and stubble fields, looking for spilt grains, invertebrates and small vertebrates.
Here is a video trying to show the extent of the flock (with sounds effects in the background from Christian).
Departing south and then cutting west, we could still hear the magnificent rattle call from at least 2 miles away. Something had at this point disturbed the cranes and they were now flying off in all directions like a huge swarm of mosquitos or even locusts on the prairie.
Now we switched our attention to our second big species of the day, the Tundra Swan. Along the southside of Plum Lakes up as far as the Grande Clariere Road we managed to count 863, another brilliant total (we had over 1000 north of here the previous day, but that’s for another blog). There were also other neat birds including 1202 Snow Goose, a single Ross’s Goose, 40 Rusty Blackbirds (globally Vulnerable) and several hundred ducks – but it was the swans which again were the highlight.
It is clear that Oak Lake remains one of Manitoba’s foremost staging areas for migrating waterfowl and other birds. The total for Sandhill Cranes easily triggers the 1% threshold for a globally significant concentration of this species and although our totals fell short in 2017, it is obvious that Tundra Swan concentrations do likewise. Targeting large seasonal concentrations of birds will be a project priority in 2018.
The cranes remained in the area on Saturday. Ken Stewart, a member of the Manitoba Birds Yahoo Group took a trip down and found them once again – see video below. We can make a couple of observations here. First, the temperature is clearly warmer. Second, there appear to be even more cranes! Christian will try to count from the video – we will try to update the blog if he manages to. We are not sure why the birds suddenly flush – possibly a raptor or a large carnivore showed some interest but this is incredible to watch!
Ken has kindly agreed to let us use his video which is copyright Ken Stewart.
You can also see more of Ken’s excellent photos on his Flikr page – https://www.flickr.com/photos/kritterspotter/with/37330706744/
Finally, it would be remiss not to mention that what we saw on Friday was just a small, but significant part of the overall Sandhill Crane population. To see something utterly astounding then you really should head to Nebraska, where over 500,000 Sandhill Cranes stage during spring migration.
Erratum – Thanks to Donna Danyluk for pointing out that Sandhill Cranes in the Platte River Valley stage en masse during spring migration – not overwinter as originally printed. See also the Rowe Sanctuary website.