#3: Expedition in Russia: Chasing goose chicks

It is only late August, but the short Arctic summer is over and autumn is upon us: Vegetation growth is slowing down, mushrooms and berries are appearing, and at night it is actually starting to become dark! It is time to get back to the Netherlands after a successful field season!

With the arrival of the second team in early July, came also the period of hatching: after a month of incubating the eggs. small goose chicks broke out of the eggs! We visited all nests to record the hatch date, and to mark the chicks with webtags. Using these tags, we can identify them when we catch them during a moult-catch, and give them metal and colourbands. The chicks sit in the nest only for a day or two, after which they follow their parents to forage on the fresh grass at the salt marshes. In a period of just 10 days, most nests hatched and the colony suddenly became a very empty and silent place.

Barnacle Goose chicks on the nest

 
“Umka”, a GPSlogger bird, remained on the nest while we webtagged her chicks

Meanwhile, Kees picked up the fieldwork on the Red-necked Phalaropes and Arctic Skuas. It didn’t take long to catch the remaining 4 Skuas, after which all 3 pairs are now equipped with geolocators. Catching the Phalaropes proved more tricky, but especially on warm days they were often present next to their nests and eventually Kees managed to catch 10 birds to equip with geolocators on their backs, using legloops. It seems the Phalaropes have an interesting incubation pattern, with long periods during which they don’t incubate the eggs, sometimes even days. We investigated this further with Ibuttons, small temperature loggers which we put in the nest to measure the length of incubation bouts. Because of the cold weather, the birds might have trouble finding food and spend long periods of the nest, but the exact reasons behind this behavior are still unknown for us. Something to look into next year!

Kees with a Red-necked Phalarope who just received a geolocator
The chick of one of the Skua pairs

Accompanying their flightless chicks, the Barnacle geese moult all their primary feathers at once, and during this period they can’t fly. Because this makes them rather vulnerable, they gather in larger groups and stay close to the water, so they can make their escape fast as soon as predators (or humans) come closer. We use this opportunity to catch the geese, driving groups on the water using kayaks, and eventually driving them in a funnel-shaped net. In this way we aimed to catch small family groups of several families, of which we equiped the females with the remaining geolocators and the males and chicks with colourbands. By doing catches of larger groups, we aimed to catch juveniles which we marked with a webtag on the nest, which we then colourbanded. Eventually we caught around 2500 geese, of which we colourbanded 352 individuals. Of all chicks which we webtagged on the nest (600), we recaptured 150, quite a good number!

Kees and Femke banding goose chicks
One of the larger group catches

In the first blogpost I wrote about the open-top chambers which we placed on Schiermonnikoog (NL) and Gotland (SE) in order to study the effects of climate change on the growing peak of grass, the main food of Barnacle Geese. Also in Tobseda we installed a setup of open-top chambers, in which we counted grass in order to calculate the change in biomass 5 times during the season. This was often a cold activity, which we sometimes had to abort because we could no longer keep hold of our pincers. With all the measurements now finished, Femke will be busy processing all the gathered samples and interpreting the results. She will present her conclusions on the NWO polar symposium on the 5th of November in the Hague.

The effects of warming are clearly visible
Counting grass in the rain

3 months of living in the Arctic, and what are the highlights besides our scientific results? It was 3 months without being disturbed by e-mails, mobile phones and the scheduling of social events, just life concentrated on the bare essentials: getting and preparing food, keeping the stove lit, and conducting the fieldwork. An easy, calm and very rewarding way of life. Also, we were enjoying nature’s gifts: fresh fish from the sea, fresh herbs from the tundra.. we can’t complain about the food!

Fish!
This Northern Hawk Owl visited Tobseda end August

But after these 3 months it is time to return to civilisation, and to get on to processing the results of the field season. We’ll keep you posted!

See you next year, Tobseda!

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