University of Iceland Researcher Studies Chick Development, Food Resources

plover chick in iceland

Postdoctoral researcher, Camilo Carneiro, at University of Iceland has spent this summer on a research project studying the development of several Icelandic bird species with regard to food resources.

The project has monitored some 110 nests, including whimbrel and plover. Laying dates and hatching success were recorded as part of University of Iceland’s ongoing monitoring of these species.

Because eggs change in density during the embryonic development, researchers are able to estimate the day of hatching with a high degree of accuracy. Once the chicks hatched, the parents were marked and measured with coloured rings.

Chicks were monitored and measured every 3 days. However, researchers have to wait until the chicks develop before also tagging them with rings, as their legs must be long enough to not interfere with their mobility.

Stool samples were also collected from the hatchlings to monitor their diet to better understand the relationship between food resources and chick development.

A particular interest in the study was the role of crowberries in hatchling diets. The berries were measured every 3 days, and estimates for the total fruit biomass available to the developing chicks were calculated.

In addition to traditional monitoring techniques, the study also employed GPS tagging to monitor their migrations patterns.

As can be seen in the above Twitter thread, once the hatchlings become independent (which generally takes around 4 weeks), they migrate non-stop to North Africa. Notably, the juveniles tend to stick together during migration.

Camilo’s research is supported by Rannís, the Icelandic Centre for Research.

Feeding Habits of Westman Islands’ Mysterious Nocturnal Birds Tracked

Leach's petrel

GPS trackers weighing just 0.95 grammes will help scientists track the movements of three species of elusive nocturnal birds that stay in the Westman Islands, South Iceland, for a part of each year, RÚV reports. The three species are the manx shearwater (Puffinus puffinus), Leach’s petrel (Oceanodroma leucorrhoa), and the storm petrel (Hydrobates pelagicus), all of which winter in the southern hemisphere – on both sides of the Atlantic.

“This has never been done in Iceland before, and we are in fact mapping the feeding areas of these species,” explained Erpur Snær Hansen, director of the South Iceland Nature Research Centre. Results from the miniscule trackers placed on Leach’s petrels and manx shearwaters have already begun to arrive, while data from the storm petrels are expected to arrive later this summer.

Travelled 600 kilometres to feed

The three species are related and are all nocturnal. “They only come ashore to the outlying Westman Islands at night, so they are rarely seen anywhere else,” Erpur stated. He compared the petrels’ flight to that of bats, saying they were “mysterious in many ways.”

The GPS trackers have revealed that the Leach’s petrels in the Westman Islands feed to the west of the archipelago, at the edge of the continental shelf. However, data shows that individuals sometimes travel much farther. “One of them decided to go all the way to Rockall, which is 600 kilometres [373 miles] to the south, and they go quite far,” Erpur remarked. “They go to the Mid-Atlantic Ridge where the big whales are, so they go south and across a very large area.”

Rockall Liam Mason
Liam Mason via Wikimedia Commons Images. Rockall, some 600 kilometres south of Iceland.

 

Numbers have decreased in the Atlantic

Placing the minuscule trackers on the birds is not easy. “It’s a bit of a hassle because they live underground, and we need to find them and get them out,” Erpur explained. “We play their call and they answer us and then we know where they live, but it’s another challenge altogether to get in there, grab them, and put the equipment on.” The GPS devices do not include transmitters, so the birds must be retrieved in order to read the data.

The Leach’s petrels that summer in Iceland winter in both Namibia and Brazil. Manx shearwaters winter in Argentina. Erpur says the species are not numerous and the number of Leach’s petrels in the Atlantic has decreased. The data is expected to help evaluate how the birds are doing, as well as compare the two petrel species.

Arctic Tern Returns to Iceland

arctic tern kría Iceland

The Arctic tern has returned to Iceland, RÚV reports. The bird is one of a number migratory birds that are making their annual return to the country this spring.

According to the records kept by the Southeast Iceland Bird Observatory, which monitors the annual arrival of migratory birds in the country, about 1,000 terns were observed in the Ósland conservation area in Höfn í Hornafjörður earlier this week.

Per their records, the first Arctic tern arrived in Iceland on April 19. This is around the same time that the first terns arrived in recent years.

The arctic tern makes the longest known migration of any animal, travelling between Arctic and sub-Arctic regions, where it breeds, to the Antarctic, where it winters, each year. Birds that nest in Iceland make a round trip that averages 70,900km (44,055mi) every year between their nesting and wintering grounds. The average arctic tern will travel some 2.4 million kilometres (1.5 million miles) during its lifetime, the equivalent of over three roundtrips from Earth to the Moon.