With the help of our volunteers and citizen scientists another year of the International Shorebird Survey (ISS) in Manitoba is in the books!

If you recall from our spring ISS round-up, this year the Manitoba IBA program officially added ISS routes in two new locations this year, the North, East and West Shoal Lakes IBA and Oak Hammock Marsh. These locations join our original two locations, Whitewater Lake IBA and Oak Lake/ Plum Lakes IBA. The program is run by Manomet and the goal of the ISS is to track long-term trends in shorebird numbers globally. The Manitoba IBA program coordinates the ISS locally in the province. With the ISS we have pre-set routes that volunteers try to visit at least 3 times in the spring and 3 times in the fall to count shorebirds on migration. You can find the results of our spring 2021 ISS surveys here.
Much like in the spring, the big story of the ISS this year was the lack of water. By the fall, my shorebird search technique was “if you are looking for shorebirds, look in areas that used to be duck habitat (i.e. deeper water)”. Any areas that were shorebird habitat in the past years was dried up by early summer!
You might ask, if we know the route will be dry, and there will be no shorebirds then why run the route at all? As the ISS is a long-term dataset it is extremely important to record shorebird numbers consistently each year, and along the same routes. This can allow us to track how changes in habitat can impact habitat use, population numbers, etc. While it may not always seem like it at the time, “zero” data are very important data to have! With that in mind let’s dive into location-specific results.
Oak Lake/ Plum Lakes IBA
Both the Oak Lake/Plum Lakes ISS routes and the Whitewater Lakes ISS routes were created back in 2018 – which was near the end of a string of high-water years. So, if the area designated for shorebird habitat was shallow water in a high-water year – you can bet that it was dry in a drought year, like this year!
Unsurprisingly, the routes at Oak Lake/ Plum Lakes IBA were largely dry, and/or the water was seen way off in the distance, outside the range of a spotting scope and the range of the ISS. Each of the 5 routes at Oak Lake/Plum Lakes was visited twice this fall, except for Route 1, which was visited 3 times.

A total of 16 species (plus undetermined Short-billed/Long-billed Dowitchers) were seen during the fall season. This included at total of 260 individuals. The proportion of each species was fairly even. The highest proportion were Long-billed Dowitchers at 15%, followed by Lesser Yellowlegs (12%), Killdeer (11%) and Wilson’s Phalarope (11%). The least common species was a single Baird’s Sandpiper.

2021 Fall Season Oak/Plum Lakes Shorebird Counts | ||
Species | Total # of Individuals | Proportion of Individuals (%) |
American Avocet | 17 | 7 |
Baird’s Sandpiper | 1 | 0 |
Greater Yellowlegs | 21 | 8 |
Killdeer | 28 | 11 |
Least Sandpiper | 16 | 6 |
Lesser Yellowlegs | 32 | 12 |
Long-billed Dowitcher | 40 | 15 |
Marbled Godwit | 9 | 3 |
Pectoral Sandpiper | 24 | 9 |
Semipalmated Plover | 2 | 1 |
Short-billed/Long-billed Dowitcher | 24 | 9 |
Spotted Sandpiper | 4 | 2 |
Stilt Sandpiper | 4 | 2 |
Upland Sandpiper | 5 | 2 |
Willet | 3 | 1 |
Wilson’s Phalarope | 28 | 11 |
Wilson’s Snipe | 2 | 1 |
Total | 260 | 100 |
A big thank you to everyone who helped out for ISS surveys at Oak Lake/ Plum Lakes including our two IBA summer students, Vicky Tang and Ariel Desrochers, our Oak Lake/ Plum Lakes IBA caretakers, Glennis Lewis and Gillian Richards, and Matt Gasner from Nature Conservancy Canada.
Whitewater Lake IBA
Like I mentioned above, Whitewater Lake ISS routes were also created during the wet spell back in 2018. However, the routes faired a bit better in terms of water levels this year than the routes along Oak Lake. This area really dried out mid-summer, the same as Oak Lake, but got several days of good showers in mid-August that revitalized water levels for a period of time (before they dried out again). We know this as the Manitoba IBA program was luckly enough to hold our bird blitz at Whitewater Lake just after those rains, and multiple local birders described to us what a difference it made, even though it was still quite dry.

The number of visits to the different routes at Whitewater Lake varied by site with the east side routes visited less often (once or twice) with the western routes visited 3-4 times each, and Sexton’s Point visited 5 times. Anecdotally, the east side seemed to dry out faster than the west side.
A total of 17 species (plus some unknown shorebirds) were seen at Whitewater Lake on fall migration counts, with a total of 1745 individuals. The distribution of species was quite a bit different than at Oak Lake. At Oak Lake the proportion of individuals was quite even, but Whitewater Lake had high counts of some species and low counts of many others. The most common species were Long-billed Dowitchers (34%), American Avocets (24%) and Sanderlings (13%). The least common species were the White-rumped Sandpiper (1 individual) and Wilson’s Snipe (1 individual). The fact that White-rumped Sandpipers were uncommon is not unexpected – they are not a common shorebird in Manitoba in general.

2021 Fall Season Whitewater Lake Shorebird Counts | ||
Species | Total # of Individuals | Proportion of Individuals (%) |
American Avocet | 413 | 24 |
American Golden-Plover | 34 | 2 |
Baird’s Sandpiper | 13 | 1 |
Greater Yellowlegs | 16 | 1 |
Killdeer | 16 | 1 |
Least Sandpiper | 89 | 5 |
Lesser Yellowlegs | 99 | 6 |
Long-billed Dowitcher | 600 | 34 |
Pectoral Sandpiper | 12 | 1 |
Red-necked Phalarope | 7 | 0 |
Sanderling | 235 | 13 |
Semipalmated Plover | 5 | 0 |
Semipalmated Sandpiper | 55 | 3 |
Short-billed/Long-billed Dowitcher | 53 | 3 |
Stilt Sandpiper | 11 | 1 |
White-rumped Sandpiper | 1 | 0 |
Wilson’s Phalarope | 10 | 1 |
Wilson’s Snipe | 1 | 0 |
large shorebird sp. | 5 | 0 |
peep sp. | 70 | 4 |
Total | 1745 | 100 |
Thank you to everyone who conducted ISS counts at Whitewater Lake including Colin Blyth and Gillian Richards (Whitewater Lake IBA Caretakers), Carla Keast, Kathryn Hyndman, Doug Ford, Carson Rogers, and our summer students Vicky and Ariel!

North, East, West Shoal Lakes IBA
The first of our new IBA blitz sites for fall 2021! The Shoal Lakes IBA and Oak Hammock Marsh ISS sites were created and scoped out last year when the water was not so high, but definitely not as low as it was this year. As a result some areas of Shoal Lake still had water a bit later in the summer/ early “fall” (as determined by ISS timing), however, most sites still eventually dried right out.
Each site at the Shoal Lakes IBA in the fall was visited 2-3 times. The total number of shorebird species seen was 9 (with some unknown peeps) and 133 individuals seen. The two most common species by far were the Greater Yellowlegs (58%) and Lesser Yellowlegs (22%). The least common birds were the Short-billed Dowitcher and White-rumped Sandpiper at one individual each.

2021 Fall Season North, East and West Shoal Lakes Shorebird Counts | ||
Species | Total # of Individuals | Proportion of Individuals (%) |
American Woodcock | 1 | 1 |
Greater Yellowlegs | 77 | 58 |
Killdeer | 2 | 2 |
Least Sandpiper | 6 | 5 |
Lesser Yellowlegs | 29 | 22 |
peep sp. | 9 | 7 |
Short-billed Dowitcher | 1 | 1 |
Spotted Sandpiper | 3 | 2 |
White-rumped Sandpiper | 1 | 1 |
Wilson’s Snipe | 4 | 3 |
Total | 133 | 100 |
A big thank you to Bonnie Chartier, Mike Karakas and Tami Reynolds who have been great about joining in our ISS monitoring at the Shoal Lakes in its first full year!
Oak Hammock Marsh
And last but not least we have the Oak Hammock Marsh ISS site to report on. This site is unique for a couple of reasons. First of all Oak Hammock Marsh is a human-restored wetland, built to bring this habitat back from largely agricultural land to its original wetland state started in 1967. The second unique thing about Oak Hammock Marsh is that the water level is actually semi-controlled though a system of dikes and culverts. It used to be entirely controlled, but the infrastructure is used less often now. However, if you have ever gone looking for shorebirds at the “front pond” (the pond just to the west of the interpretive centre front doors) just know that you have centre staff to thank for keeping it at just the right height for shorebirds! And the third unique thing about Oak Hammock Marsh is the Shorebird Scrape – additional human-made shorebird habitat created last fall adjacent to a small lake – the first of its kind in Manitoba!
Oak Hammock Marsh probably was the site that was best retaining water this year as it has areas of varying water depths all close together. So although areas that were normally shallow dried out, there were areas that normally have higher water that turned shallow this year, but still stayed wet.
Two routes at Oak Hammock Marsh were visited twice in the fall, and one route was visited once. There were 9 species of shorebird seen during ISS visits, and a total of 228 individual shorebirds counted. The most common species were Greater Yellowlegs (64%), Lesser Yellowlegs (12%) and Killdeer (11%). There were several species that were only counted twice on ISS surveys including the Least Sandpiper, Spotted Sandpiper, Upland Sandpiper and Willet.

2021 Fall Season Oak Hammock Marsh Shorebird Counts | ||
Species | Total # of Individuals | Proportion of Individuals (%) |
Greater Yellowlegs | 147 | 64 |
Killdeer | 24 | 11 |
Least Sandpiper | 1 | 0 |
Lesser Yellowlegs | 28 | 12 |
Semipalmated Plover | 9 | 4 |
Spotted Sandpiper | 1 | 0 |
Upland Sandpiper | 1 | 0 |
Willet | 1 | 0 |
Wilson’s Snipe | 16 | 7 |
Total | 228 | 100 |
Bonnie, Mike and Tami were instrumental in collecting our ISS monitoring data at Oak Hammock Marsh as well as at the Shoal Lakes IBA and were joined at Oak Hammock by Tim Poole. Thanks all!
ISS Round-Up
While this may have not been the most exciting year for shorebirds on migration due to the difficulty in finding them with the low water levels, it is an incredibly important year in recording the numbers (or lack of numbers). There is a lot of winter and chance for precipitation between us and the Spring 2022 ISS season, so we will keep our fingers crossed that it will be a bit wetter next year!
As you can see from the numbers of times we were able to run ISS routes, we’d love to have a few more volunteers to consistently reach our targets of visiting each site 3 times in the spring and 3 times in the fall. You do not have to run all the ISS routes in a location in a day – pick one or two that fit with where you normally bird! While you do have to record all shorebirds, you are also free to record the other birds you see as well, just like normal birding. If you visit any of the ISS site during the spring or fall, just send me an email at iba@naturemanitoba.ca and we can see if running an ISS route might be of interest to you!
-Amanda