A Waterbird Inventory of the Darkhad Depression, Kbovsgol, Mongolia

• Main Author: Call, Mikayla
• Format: Text
• Language: unknown
• Published: Digital Commons @ ESF 2018
• Subjects: birds; waterbirds; waterfowl; Mongolia; Ornithology; Eurasian Curlew; Mergellus albellus; Numenius arquata; smew
• Online Access: https://digitalcommons.esf.edu/honors/138; https://digitalcommons.esf.edu/cgi/viewcontent.cgi?article=1141&context=honors

The Darkhad Depression, Khövsgöl aimag, Mongolia has an abundance of rivers, lakes, and pothole wetlands, providing one of the most extensive concentrations of waterbird habitat in Mongolia. Waterbirds use the wetlands of the Darkhad Depression for breeding, molting, and as stopover sites during migration. As far as we are aware, our survey of waterbirds in this region is the first to provide broad wetland coverage of the Darkhad Depression. We conducted a survey of waterbirds in the Darkhad Depression in Tsagaannuur and Renchinlhumbe soums and compared densities of waterbirds between two lakes with subsistence fishing and those without. We surveyed 60 lakes (5867.26 ha) and a 5.4 ha portion of a river for waterbirds. We observed 39 species and calculated their frequency of occurrence among lakes and densities among occupied lakes (birds/ha). Common goldeneyes (Bucephala clangula) and tufted ducks (Aythya fuligula) had the greatest estimated densities for the Darkhad Depression (0.3 birds/ha), whereas common greenshank (Tringa nebularia), Eurasian curlew (Numenius arquata), smew (Mergellus albellus), and black stork (Ciconia nigra) had the least (< 0.0001 birds/ha). Tufted ducks had the highest mean density on used lakes (6.66 ± 5.69 birds/ha), and common goldeneye used the highest percentage of wetlands (57.38% of surveyed wetlands). We detected that piscivorous waterbird densities on two lakes that were historically overfished were 79% less than those on lakes of similar size, suggesting that overfishing could be a threat to these birds in the Darkhad Depression. We recommend that future studies conduct more extensive surveys of waterbirds over a longer surveying period and earlier in the breeding season, so that more species can be counted with their young and a more complete inventory of waterbirds can be created.