Habitat use of barnacle geese at a subarctic salt marsh in the Kolokolkova Bay, Russia

Along the east Atlantic migratory flyway, goose and swan species rely on the availability of suitable coastal habitats as staging sites during migration and for breeding. Especially for the Russian part of the flyway, detailed descriptions of these habitats in relation to use by herbivores are lacking. We report on salt-marsh characteristics and habitat use by barnacle geese in a recently established breeding site, near the village Tobseda at Kolokolkova Bay in the Pechora Delta, Russia. A classification of plant communities was made and both vegetation and soil properties were measured. Goose visitation was assessed by counting droppings. From the bay towards the dunes there was a gradient of decreasing salinity, along with a gradual shift in plant communities from salt marshes to freshwater bogs, tundra and dunes. Barnacle geese visited salt-marsh communities of the low and middle marsh more than the high marsh and non-saline communities. Two low marsh communities were preferred. Both had high tiller densities and low canopy heights and were dominated by Carex subspathacea, a species with high forage quality. Those characteristics are selected by geese, but might be maintained through grazing. The salt marsh at our site bears similarities to other marshes at similar latitudes along the Russian coast and in Canada. We discuss whether processes like grazing facilitation and habitat degeneration through overgrazing occur on our site

Winter air temperature during the Holocene optimum in the north-eastern part of the east European plain based on ice wedge stable isotope records

Early Holocene winter air temperatures have been reconstructed for the northeastern part of the East European Plain using stable isotope (δ18O and δ2H) records of syngenetic ice wedges. We show that ice wedges here actively grew synchronously with accumulation of peatlands in bogged and forested depressions between 10 and 8 cal ka BP, corresponding to the early Holocene Thermal Maximum. The slope of the δ2H-δ18O regression line is close to the global meteoric water line. This suggests the preservation of winter precipitation signal in the ice wedge with minor isotope transformation. The low range of stable isotope values in the ice wedge indicates quite stable winter climate conditions, favorable to ice wedge growth. Reconstructed mean winter air temperature was close to modern, but it is assumed that air temperature of the coldest winter month was lower and more stable than at present