Joonam Reservoirs & Western Nakdong Estuary, November 30

Bird News from Nial Moores with Jason Loghry

Bird News from Nial Moores with Jason Loghry

In heavy, dull and dark overcast with occasional spells of rain and misty drizzle – a prelude to the end of autumn and the start of real winter weather – a total of 93 species logged. Selected highlights included single adult Lesser White-fronted Goose, Eastern Marsh Harrier (at the Nakdong), male Red-flanked Bluetail and Lapland Longspur (latter heard only: this species appears usually to be genuinely scarce in the southeast of the country); a dozen Baikal Teal, seven White-naped Crane and three Eurasian Hoopoe; a single loose flock of 4,700 Mallard out of c. 6,000 seen during the day; in total perhaps 500+ Oriental Turtle Dove, 150+ Far Eastern and 10+ Eurasian Skylarks, 350+ White-cheeked Starling and c. 20 Common Starling (more evidence of this latter species’ recent increase); and hybrid combinations of two Red-billed x White-Cheeked Starlings (but no pure Red-billeds) and single hybrid Mallard x Eastern Spot-billed Duck and presumed Eurasian Wigeon x American Wigeon.

Lesser White-fronted Goose Anser erythropus, © Nial Moores

Common Starling Sturnus vulgaris, © Nial Moores

Red-flanked Bluetail Tarsiger cyanurus, © Nial Moores

Hybrid Red billed and White cheeked Starling (right) and Common Starling Sturnus vulgaris (left), © Nial Moores

Hybrid Red billed and White cheeked Starling, © Nial Moores

We also enjoyed excellent views of “big-billed” middendorffii Taiga Bean Geese at Joonam. These included one (out of 300+ close birds) with an almost completely dark bill (shown in the image), and another seen more distantly, also with very limited paler orange on the bill sides, unfortunately not digiscoped. Although several online and published sources state that juvenile bean geese can show duller bare part coloration than adults, both of these dark-billed birds help illustrate yet another facet of what appears to be great variation in bill patterning and especially structure shown by middendorffii that overwinter in the ROK. As noted over the years, in addition to presumed male / female differences and individual variation within populations, Taiga Bean Geese appear (to me at least) generally biggest-bodied, biggest-headed and longest-billed in the southeast of the country (often with little bill “grin”), e.g. at Upo, Joonam and in the Nakdong Estuary; apparently thinner-billed and thinner-necked looking at some other sites (e.g. sometimes in the southwest); and often rather closer in appearance to Tundra Bean Goose in the west and northwest (with less slope to the forehead and more of a “grin”), at Saemangeum, the Geum Estuary, Seosan and Baekryeong, where groups of Taiga and Tundra can often be seen side-by-side. Many of these differences in perception might well be down to differences in viewing conditions and distance (best at the Nakdong, worst at Saemangeum). However, might they also be the result of differences in origin of breeding populations and winter feeding ecology, with subtly different feeding opportunities available in different parts of the country in winter, e.g. between the often frozen northwest and the much milder, usually unfrozen southeast? Fellow Birds Koreans: more images of bean geese please!

Taiga Bean Goose Anser fabalis middendorffii with dark bill, © Nial Moores

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