Stejneger's Scoter Melanitta stejnegeri Scientific name definitions

51–58 cm; male 1020–1437 g, female 957 g (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ); wingspan 86–99 cm (2 Brazil, M. (2009). Field Guide to the Birds of East Asia: Eastern China, Taiwan, Korea, Japan and Eastern Russia. Christopher Helm, London, UK. Close ). Large Melanitta. Recognizable in flight  by conspicuous white secondaries and greater coverts that form square wingbar (usually just visible on closed wing). Male  glossy blackish (duller in non-breeding season, with pale-mottled flanks) (3 Proctor, B. and Pullan, D. (1997). Identification of Velvet and White-winged Scoters. Birding World. 10(2): 56–61. Close ); pale grey-white eye with white mark below it; legs and feet red-pink with blackish webs (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). Female medium to dark brown with paler greyish-brown patches between eyes and bill and adjacent to ear-coverts; bill dull olive-black, dark grey or black, feet dull reddish, and irides brown (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). Juvenile as female, paler on breast with whiter and larger pale head markings; bill may become coloured during early spring, but lacks basal swelling of adult; only assumes adult plumage in second autumn; juvenile male is generally dull brown to black, variably mottled with black on upperparts (especially from Dec onwards) (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). Compared to M. fusca, with which this species and deglandi were both previously considered as conspecific (see Taxonomy comments), stejnegeri is separated mainly by shape and colour of bill (3 Proctor, B. and Pullan, D. (1997). Identification of Velvet and White-winged Scoters. Birding World. 10(2): 56–61. Close ): male stejnegeri  differs from nominate race in larger bill knob, darker, more orange on upper part and red or reddish purple on lower edge, with amount of black on cutting edges variable (sometimes appears absent) and that at base generally more extensive than nominate fusca (3 Proctor, B. and Pullan, D. (1997). Identification of Velvet and White-winged Scoters. Birding World. 10(2): 56–61. Close ); male deglandi has olive-brown flanks (feathers with paler fringes and can appear very mottled when faded) (3 Proctor, B. and Pullan, D. (1997). Identification of Velvet and White-winged Scoters. Birding World. 10(2): 56–61. Close ), while bill characters differ subtly from stejnegeri, with less prominent knob (3 Proctor, B. and Pullan, D. (1997). Identification of Velvet and White-winged Scoters. Birding World. 10(2): 56–61. Close ): black basal knob bleeds further forward onto distal half of culmen on stejnegeri (this area is whitish in deglandi), rim of distal half of bill has narrow yellow or reddish-orange band on stejnegeri (black on deglandi) and where reddish-coloured area on bill sides meets black in basal half, the border is more often concave or straight in stejnegeri (but usually convex in deglandi) (4 Garner, M. (1999). Identification of White-winged and Velvet Scoters – males, females and immatures. Birding World. 12(8): 319-324. Close ). Female/first-year stejnegeri has a slightly taller, more swollen culmen base than deglandi, and the forehead feathering does not extend prominently onto the culmen (unlike deglandi) (4 Garner, M. (1999). Identification of White-winged and Velvet Scoters – males, females and immatures. Birding World. 12(8): 319-324. Close ).

Breeds in eastern Asia, from Altai, Russia, to the Kamchatka Peninsula (6 Collinson, M., D. T. Parkin, A. G. Knox, G. Sangster and A. J. Helbig. (2006a). Species limits within the genus Melanitta, the scoters. British Birds 99 (4):183-201. Close ), south to Mongolia; locally in northeastern Kazakhstan. Occasional occurrences are reported on the lower Yenisey River to Dudinka, but the limits of the breeding range are likely farther east (7 Dement'ev, G. P., N. A. Gladkov, Y. A. Isakov, N. N. Kartashev, and S. V. Kirikov (1952). Birds of the Soviet Union. Volume 4. Israel Program for Scientific Translations, Jerusalem, Israel. Close , 8 Rogacheva, H. (1992). The Birds of Central Siberia. Husum Druck-und Verlagsgesellschaft, Husum, Germany. Close ). There is a possible discontinuity in range in the southern part of the Angara area (8 Rogacheva, H. (1992). The Birds of Central Siberia. Husum Druck-und Verlagsgesellschaft, Husum, Germany. Close ). Winters along coasts of Kamchatka, Sea of Okhotsk, and Commander Islands south to Japan, Korea, and eastern China.

Breeds around small freshwater bodies of boreal forest and Arctic tundra, sometimes well inland, but in Kazakhstan breeds at 1,760–2,300 m (9 Wassink, A., and G. J. Oreel (2007). The Birds of Kazakhstan. Published privately, De Cocksdorp, Texel, The Netherlands. Close ). Winters mostly at sea (and juveniles also spend whole of first year at sea) (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ), usually in shallower waters of littoral zone, and species is periodically recorded inland elsewhere virtually throughout its range in small numbers at this season.

Migratory; winters on coasts of NE Asia S to Japan and E China; also inland. Prior to leaving vicinity of breeding grounds, those in E Asia mass off Okhotsk coast with smaller numbers on lakes in Kamchatka and on Sakhalin (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). Migration routes poorly known, but an estimated 140,000 pass Kamchatka in spring, with totals of up to 40,000 per hour (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). In Kazakhstan, where both M. fusca and the present species breed, former occurs on spring passage between mid Apr and late May, and in autumn mid Sept to late Nov, whereas stejnegeri arrives on breeding grounds late May/early Jun and departs late Jul–Oct (9 Wassink, A., and G. J. Oreel (2007). The Birds of Kazakhstan. Published privately, De Cocksdorp, Texel, The Netherlands. Close ). Records of vagrants in Afghanistan (Jan) and Pakistan (Feb 1988) might pertain to fusca but perhaps to stejnegeri (10 Rasmussen, P. C., and J. C. Anderton (2005). Birds of South Asia: the Ripley Guide. Lynx Edicions, Barcelona, Spain. Close ). Elsewhere, stejnegeri has been reported as a vagrant in Denmark (Oct 2009, Mar 2010 and Feb–Mar 2011, all presumed the same returning individual) (11 Farrar, D. and Jones, J. (2011). The Stejneger’s Scoter in County Kerry. Birding World. 24(3): 105–112. Close ), SW Finland (May–Jun 1996, May–Jun 2012) (12 Lindroos, T. (1997). Rariteettikomitean hyvaksymat havainnot vuodelta 1996. Linnut. 32(6): 18–30. Close , 13 Gibbins, C., Baxter, P. and Maggs, H. (2015). White-winged Scoter in North-east Scotland: new to Britain. British Birds. 108(3): 168–175. Close ), N France (Dec 1886) (14 Jiguet, F. and the CAF (2007). Première mention pour la France de la Macreuse à ailes blanches sibérienne. Ornithos. 14(1): 38-42. Close ), Iceland (Apr–May 2003) (15 Kolbeinsson Y., Thràinsson G. and Pétursson G. (2006). Sjaldgæfir fuglar á Íslandi 233333. Bliki. 27: 27-50. Close ), Ireland (Nov 2009, Jan 2010 and Dec 2010–Mar 2011, all same bird) (11 Farrar, D. and Jones, J. (2011). The Stejneger’s Scoter in County Kerry. Birding World. 24(3): 105–112. Close ), Norway (Jun 2011, Jul–Aug 2015, several in 2016) (13 Gibbins, C., Baxter, P. and Maggs, H. (2015). White-winged Scoter in North-east Scotland: new to Britain. British Birds. 108(3): 168–175. Close , 16 Ławicki, Ł., and A. B. van den Berg (2015). WP reports. Dutch Birding 37(5):340–353. Close , 17 Ławicki, Ł., and A. B. van den Berg (2016) WP reports. Dutch Birding 38: 322–336. Close ), N Poland (Mar 2007) (11 Farrar, D. and Jones, J. (2011). The Stejneger’s Scoter in County Kerry. Birding World. 24(3): 105–112. Close ) NW Spain (Dec 2011–Jan 2012) (18 van den Berg, A.B. and Haas, M. (2012). WP reports. Dutch Birding. 34(1): 49–62. Close ) and Sweden (May 2012, May 2014) (19 van den Berg, A. B., and M. Haas, (2014). WP reports. Dutch Birding 36(3):195–208. Close , 13 Gibbins, C., Baxter, P. and Maggs, H. (2015). White-winged Scoter in North-east Scotland: new to Britain. British Birds. 108(3): 168–175. Close ); it has also occurred at least twice in W Alaska (May 2001, Jun 2002) and might even prove to be reasonably regular there (20 Garner, M., Lewington, I. and Rosenberg, G. (2004). Stejneger’s Scoter in the Western Palearctic and North America. Birding World. 17(8): 337-347. Close ).

Mainly molluscs; also crustaceans, worms, echinoderms, annelids (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ), small fish and, in fresh water, insects and their larvae. Little plant material consumed, principally on breeding grounds, where diet of M. fusca and M. deglandi is dominated by amphipods, caddis fly larvae and crustaceans (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). Winter diet mainly saltwater molluscs, but in Japan feeds mainly on crabs (Pinnixa ratubuni) at depths of 30–40 m. Feeds almost exclusively by diving, propelling themselves using both wings and feet (21 Richman, S.E. and Lovvorn, J.R. (2009). Predator size, prey size and threshold food densities of diving ducks: does a common prey base support fewer large animals? Journal of Animal Ecology. 78(5): 1033-1042. Close ), though occasionally also dabbles on surface.

Usually silent, like M. fusca and M. deglandi, but mentioned are a whistled “fee-er” by displaying male and a low nasal “aah-er”, while female gives a gruff croaking “kraa-ah kraa-ah kraa” (2 Brazil, M. (2009). Field Guide to the Birds of East Asia: Eastern China, Taiwan, Korea, Japan and Eastern Russia. Christopher Helm, London, UK. Close ).

Poorly known compared to M. fusca and M. deglandi. Generally starts May/Jun.  Seasonally monogamous; pairs may defend small territory around nest-site (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). In single pairs or loose groups (e.g. on islands), sometimes in association with gull and tern colonies, in wooded boreal or taiga country (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). Nest is shallow depression poorly lined with surrounding plant matter, and also with down, on ground among vegetation. Single-brooded (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ). Usually 6–9 eggs (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ), laid at rate of one every 1·5 days (22 Traylor, J.J., Alisauskas, R.T. and Kehoe, F.P. (2004). Nesting ecology of White-winged Scoters (Melanitta fusca deglandi) at Redberry Lake, Saskatchewan. Auk. 121(3): 950-962. Close ); creamy buff (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ) or yellowish white (23 Adamian, M. S., and D. Klem (1999). Handbook of the Birds of Armenia. American University of Armenia, Yerevan, Armenia. Close ) in colour, size 55·4–72·5 mm × 35·7–49 mm (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ); incubation period unknown, by female alone; chicks have dark brown down above, white below up to cheeks, neck-sides and lower throat (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ); fledging c. 50–55 days. One instance of apparent parasitism by this species on Aythya fuligula (24 Liu, Y. and Pyzhjanov, S. (2012). Apparent inter- and intraspecific brood-parasitism in a nest of Tufted Duck Aythya fuligula. Forktail. 28: 147–148. Close ).

Not globally threatened (Least Concern). Population probably declining and has been estimated 400,000–700,000 individuals, of which potentially c. 1% winter off NE North Korea (25 Moores, N. (2018). Birds and their conservation in Rason Special Economic Zone, Democratic People’s Republic of Korea. Forktail 33:124–133. Close ). In breeding range, decline registered in Kazakhstan, while anecdotal evidence alone also indicates losses, e.g. along Lena R in Yakutia numbers said to have declined by up to ten-fold during 1970s (1 Kear, J., Editor (2005). Ducks, Geese and Swans. Volume 1: General chapters, and Species accounts (Anhima to Salvadorina). Oxford University Press, Oxford, UK. Close ), but robust data are especially sparse for this member of the M. fusca complex. Apart from risk of large congregations of birds being affected by oil spills (for example, Melanitta species showed evidence of long-term and increasing negative effects as a result of Alaskan Exxon Valdez disaster) (26 Lance, B.K., Irons, D.B., Kendall, S.J. and McDonald, L.L. (2001). An evaluation of marine bird populations trends following the Exxon Valdez oil spill, Prince William Sound, Alaska. Marine Pollution Bulletin 42(4): 298–309. Close ), the species is threatened because it feeds at depths of 30–40 m and thus is very prone to being trapped in fishing nets (even discarded fishing gear (27 Good, T.P., June, J.A., Etnier, M.A. and Broadhurst, G. (2009). Ghosts of the Salish Sea: threats to marine birds in Puget Sound and the Northwest Straits from derelict fishing gear. Marine Orn.. 37(1): 67–76. Close ) and lead sinkers (28 Scheuhammer, A. M., S. L. Money, D. A. Kirk, and G. Donaldson (2003). Lead Fishing Sinkers and Jigs in Canada: Review of Their Use Patterns and Toxic Impacts on Wildlife. Occasional Papers 108. Canadian Wildlife Service, Ottawa, Canada. Close ) can represent lethal hazards). N Pacific populations of this species (and other seaducks) have been shown to be highly susceptible, for short periods, to broad-scale oceanic regime changes, which affect both biological and climatic variables; however, it is presently unknown how these changes negatively impact bird populations, either through reduced survival chances or reproductive failure (29 Flint, P.L. (2013). Changes in size and trends of North American sea duck populations associated with North Pacific oceanic regime shifts. Marine Biology. 160(1): 59–65. Close ).