Birds News by Leslie Hurteau, with additional commentary by Nial Moores
On Sunday November 4th and Monday November 5th, some time was spent in the field birdwatching with Dr. Nial Moores, who was visiting Jeju Island for work related reasons. We started Sunday morning off on the east coast, where we looked for a female Canvasback that was spotted earlier in November, presumably the same individual that was in the same area the past two years. After a false start at the wrong spot (oops) we located the Canvasback at a quiet spot in Seongsan wetland where she had been spotted last year. We enjoyed the views until the Canvasback retired on a rock for rest, giving us our cue to move on to Hado wetland, one of the best spots for birdwatching on Jeju.
Link for eBird checklist is here: Seongsan Wetland.
At Hado wetland, we found a wide range of wintering waterfowl including species such as the expected Eastern Spot-billed Ducks, Gadwalls, Common Shelducks, Northern Lapwings, and Black-faced Spoonbills (Jeju is still a good spot for them in winter), and songbirds, such as Pallas’s Reed Buntings, Light-vented Bulbuls, and a couple of Eastern Yellow Wagtails flying over. Black-faced and Masked Bunting calls caught our attention, and we waited patiently for them to show so we could have the chance for a visual comparison. The buntings didn’t cooperate, unfortunately, but while waiting an Eurasian Bittern flew over the reeds giving brief views, and an Eastern Buzzard captured a Green Sandpiper. From the car, Dr. Moores spotted a gull-like bird with a black cap, which may have been the local Caspian Tern (a species in recent winters known to overwinter on the east of Jeju). We couldn’t relocate it, so we decided to move on.
Link for eBird checklist here: Hado Wetland.
From here we moved down along the coast, stopping occasionally to check flocks of gulls and see what shorebirds are on the coast and for any possible seabirds. Mainly Vega Gulls were found, as well as some Taimyr, Slaty-backed, Mongolian, two Saunders’s, and one surprise Common Gull (not so common on Jeju). We made it to Seopjikoji to scan the sea for any interesting seabirds. Unfortunately, aside from two Black-legged Kittiwakes (seen by NM only), and a Pelagic Cormorant or two, there was not much to write home about. So, on we went a bit further to some city parks in downtown Seogwipo, the biggest city on the south coast of Jeju.
A Scaly-sided Merganser that was in Seogwipo a couple weeks ago (seen by LH) had unfortunately moved on, which left us searching for any interesting buntings along steep slopes heavily shaded by vegetation. A few possible Grey or Tristam’s Buntings were heard, but we decided to move to the last spot, Hanon Crater, which is one of the only places on Jeju where rice is grown. A brief search at dusk came up with another possible Grey Bunting calling, a possible Woodcock seen by NM, and a Tundra Bean Goose heard flying over. It was a quiet ending to a pleasant trip along the east and south coasts of Jeju.
The next morning was spent on the opposite side of the island, at the Halla Arboretum in Jeju City. We were in search of a Ryukyu Minivet I had spotted there on November 18th. Luck was on our side as within moments of arriving we heard Ryukyu Minivet calls, and soon spotted not one but two individuals (one male and one female) perched high up in a deciduous tree. The views were brief so we continued the search to relocate them. We heard the calls a few more times in different locations, and even had a quick flyover, before the minivets became quiet leaving us with the resident Warbling White-eyes, Brown-eared Bulbuls, Eastern Tits, Pale Thrushes, and two Yellow-browed Warblers.
Further exploring through the forested areas led us to discover three or four Grey Buntings, two of which were seen somewhat well. I had to move on at this point, but Dr. Moores stuck around for a chance to relocate the minivets. He relocated them later in the afternoon, and not just two but a group of seven where the earlier two were spotted, feeding on insects in trees, initially low-down with Eastern Great Tits, and then in the canopy with Warbling White-eyes and Brown-eared Bulbuls. This incredible finding was a perfect ending to a couple days of birdwatching on Jeju Island.
Link for eBird checklist is here: Halla Arboretum.
The sighting of Ryukyu Minivets in Halla Arboretum coincided with 3-4 Ryukyu Minivets seen and photographed in Jeonju on the mainland on the same day, as well as another individual spotted on the south coast of Jeju on November 27th.
Additional status note by NM (revised on December 14th 2022): Following the first national record found and photographed in May 2013 by Matt Poll, the seven or eight subsequent adequately-documented records in the ROK of Ryukyu Minivet now come from between November and May with the majority on Jeju or islands in the southwest of the Peninsula, with the exception of 3-4 inland in Jeonju in November 2022 and now two records in the southeast: one sound-recorded in Namhae County on February 7th 2021 (Kim Gayoung et al. in Korean Journal of Ornithology 2021), and one seen and photographed in a coastal park in Busan on December 13th 2022. Up to December 14th, there have been at least 14 individuals observed in the ROK this autumn / early winter. There are also several undocumented claims of “possibles” (including birds I heard calling on Geoje Island in June 2002) and one historical specimen from late September 1915 from Pyonganbukdo, in present-day DPRK, considered without explanation to be “questionable” by Austin (1948), which was subsequently incorrectly said to be in the ROK by Brazil (1991). Based on the pattern of records in Japan in recent decades (see below) and a series of records along the Chinese coast (south to Hong Kong in 2021) it seems likely that these recent records of Ryukyu Minivet in the ROK are more the result of rapid range expansion, related in one way or another due to the warming climate and the exploitation perhaps of a new ecological niche, than due e.g., to increased awareness of the species alone – though this of course will also have played a major role (i.e., more skilled birders looking in more places with better cameras, allowing the IDs to be confirmed independently).
The Ryukyu Minivet remains a rather enigmatic species, which was only split fairly recently from the much more widespread and rather similar-looking Ashy Minivet. In the field, Ryukyu looks a little shorter-tailed and obviously darker above and below than Ashy (slaty-grey rather than ashy-grey), with greatly reduced white on the wing and forehead. The underparts are also washed more thoroughly with dark grey than in Ashy too. The calls are flatter, less melodic, to my ears sounding more like a muffled Bohemian Waxwing trill, with the trill very often – but not always – repeated twice in rapid succession.
Brazil’s monograph on the Birds of Japan (published in 1991) describes Ryukyu Minivet as a resident endemic to the Nansei Shoto (the islands south of Kyushu), with a few mid-winter “vagrant” records from Kyushu. By the 1990s, the species was increasingly recorded to the north of its rather narrow breeding range, with flocks wintering in forest in e.g., Miyazaki Prefecture in SE Kyushu, and individuals and small groups sometimes reaching as far north as Fukuoka Prefecture. Brazil (1991) also notes that Ashy Minivet sometimes wintered in Kyushu, but in retrospect it seems more likely that most (all?) of these records more likely would have been Ryukyu Minivet (especially as the 1974 Checklist of Birds of Japan apparently suggested that Ryukyu was resident in Miyazki Preferecture: see Brazil 1991). Either way, during the past twenty years, the Ryukyu Minivet appears to have been confirmed as a breeding species in parts of Kyushu, and according to the online Birds of the World, also in western Honshu and Shikoku. Ryukyu Minivet is now also recorded with some frequency in winter as far north/east as Tokyo, with all records on eBird from the Tokyo region coming from September to late March – as opposed to Ashy Minivet which on eBird has only been recorded in the Tokyo region from April to late October.
The seasonal pattern of records of both of these minivet species in Japan seems rather similar to the emerging pattern in the ROK. Ashy Minivet is a locally common seasonal migrant (April-May and early June?; and August to early November) and local summer visitor, found in both cold temperate and warm temperate deciduous and mixed forest, with scattered breeding pairs nationwide throughout the summer (including in recent years e.g., a juvenile photographed in early July in Goheung in 2015; an adult in Yeoncheon in early June 2020; and a pair in Busan throughout June into July 2021). Ryukyu Minivet appears largely to be a winter visitor to warm temperate mixed forest and parkland – with records in spring perhaps of displaced birds trying to return south to the breeding range (?). Future colonisation of parts of the ROK as a breeding species now seems highly probable (especially in warm temperate forest on Jeju). Based on the proximity to Japanese breeding grounds, it seems likely that in the future Ryukyu Minivet will also be found more often in coastal forest and parks in the mild southeast too, either as a winter visitor or perhaps even as a resident.