Thursday, June 10

Working with Hudwits

Stilt Sandpiper

In the past few days, before our boss Nathan Senner's arrival on Tuesday, Shawn Billerman, Brad Walker and I spent most of our time searching for Hudsonain Godwit nests and finishing setting up insect transects. We focused most of our efforts on the Fen, where most of the local Godwits nest. The Fen is a massive and disorientingly open bog with a few scattered tamaracks and island of dry lichens. A north-south dirt road (if it can be called that- it is more pothole than road), called Twin Lakes, divides it into two portions, and as you look in any direction from the car, the expanse of sedges interspersed with pools and soggy areas stretches as far as the eye, until those bare tamaracks, few and far between, accumulate on the horizon as a dark tree line, constantly crawling from the heat.
As we set up transects, I kneel in the soggy peat and slice a circular plug out of the ground with a serrated kitchen knife. As I slide my fingers down the edge to pull it out, my fingers immediately throb in the freezing water- just centimeters above the permafrost- even on a 65 degree day like this. I slide a plastic cup into the hole, pour in about an inch of isopropyl, and head off to the next point, 100 meters away. Between two such points, on one fateful day, Shawn happened to look up from the transfixing sight of boots sinking into the wet spongy peat to see a jeager flying over. When I glanced up, the first thing I noticed was a surprisingly long stream of feathers trailing behind the graceful bird- it was, finally, a Long-tailed Jaeger! These are regular but quite uncommon migrants through the Churchill area as they head to their breeding grounds to the north. Later that same day, the first Smith's Longspurs arrived, and Brad and I found several males singing at the south edge of the Fen as we were finishing an insect transect.

The last two days with Nathan have been immensely tiring. On Wednesday, we woke around 6:00 in order to finish checking our daily insect traps before breakfast, and then we split into two groups and covered as much ground as we could in the Fen looking for nests. As soon as we heard a male godwit calling, we would scan the sky for the alarmed bird and follow him until he landed in the sedges or alighted atop a spruce. From there, we would determine whether he was tied very closely to a territory, and whether or not he had a nest with a full clutch yet (they are usually agitated by our approach but tend to leave the area more readily if they do not yet have four eggs). If there was certainly a nest in the area (hopefully with an incubating female), we would meticulously scan the area, walking back and forth as if mowing a lawn and looking down onto sedge mounds with dwarf birches, where they tend to build their nests. We ended up finding several territories and "scrapings (the beginnings of potential nests by males, to be chosen from by females) and two nests with eggs.

Photo by Shawn Billerman

Today, we spent another 9 hours of hard walking in the Fen, going visiting the 8 active nest sites that we have GPS coordinates for so far, and capturing and banding those birds. To do so, we would approach to about 60m of a nest, and set up the banding kit and mist net, which is a very thin, 12-meter net spread between two aluminum poles, each one held parallel to the ground by me and Nathan. We would approach the nest in this manner, and hopefully lay down the net over the incubating bird before it flushed-- this worked on 7 of the 8 nest we visited. Once a bird was caught, we would take the standard measurements and a blood sample, and then, to it's left leg, attach a flag with a two-letter combination and a "data logger" glued to it. These data loggers are light sensors that, once calibrated, record the times of sunsets and sunrises until the bird is recaptured. In this way, the bird's migration route and other movements can be accurately tracked because such timing data can give you the latitude and longitude on any given date.

Photo by Geoff Legault

The photography will certainly be taking a rest for a while now, as we are covering much more ground, carrying much more gear, and spending many more hours in the field at work. Hopefully on the off days, I will be able to catch up on some of the new arrivals, such as the Smith's Longspurs.

Red-necked Phalarope

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