Bird News from Nial Moores and Jason Loghry
In largely mild (5C- 10C) and overcast conditions with light to moderate southwesterly winds, clearing to sunny and almost calm conditions in the later afternoon, another fascinating day was spent at Guryongpo trying to learn more about seabird movements along the east coast.
Most of the day was spent with NM counting from nine different points along the headland followed by two timed counts of birds moving south during a period of massive movement (two spells of twenty minutes between 14:05 and 15:15), all through a truly superb Swarovski scope; and JL checking through the mass of birds which were closer to shore and trying to capture a few images. This was followed by the last hour or so of the day looking through gulls, during which time the highlight was an apparent First Cycle American Herring Gull.
Highlights on and over the sea included:
- Brant Goose 흑기러기. One.
- “Asiatic” White-winged Scoter 검둥오리사촌. A total of 63.
- Harlequin Duck 흰줄박이오리. Only 18 seen, though these included a gang of three males actively courting a female, with head-throws, running across the water and diving towards her. The female seemed to prefer the advances of one of the males rather more than of the others, actively driving off the other two and eventually swimming off with her choice of the day.
- Long-tailed Duck 바다꿩. One still.
- Red-throated Loon 아비. This was the commonest loon identified to species, with at least 257 counted (compared to only 12 Arctics and five Pacifics). In addition, several large groups of loons were seen trying to depart to the southwest shortly after dawn (with one such flock containing 140 birds circling high, some departing overland and others heading back north). There were an additional 110 or so seen too far off on the water from the other count points to ID to species and an estimated 150 loons per hour moving south around the headland in the late afternoon. Most of these looked likely also to be Red-throateds.
- Yellow-billed Loon 흰부리아비. One or perhaps two (?) were seen in flight off the headland in the late afternoon.
- Great Crested Grebe 뿔논병아리. A total of 331 were counted in the bay and probably 10-20 an hour were also seen moving south round the headland in the late afternoon.
- Horned Grebe 귀뿔논병아리. This year’s research suggests that this is perhaps the latest of the grebes to arrive in Korean waters, with none in Goseong a couple of weeks ago and the eleven counted the first this season that we have seen here.
- Black-necked Grebe 검은목논병아리. A total of 258 were counted. This species was Red-Listed by Birds Korea in 2014; and this area is among the most important wintering sites for the species nationally.
- Brunnich’s Murre 흰줄부리바다오리. A large murre with largely dark and heavy-looking head seen flying south by NM was presumably this species.
- Long-billed Murrelet 알락쇠오리. A total of seven were seen (two in flight and five feeding).
- Ancient Murrelet 바다쇠오리. This was easily the most numerous bird during the day, with many birds necessarily left uncounted as we moved between sites and I tried to count only up to and not beyond certain landmarks at each count point. A total of 13,400 were counted within the bay itself, with probably a third of these sitting and the remainder flying into and then back out round the headland in a movement that might well have been going on all day and had certainly started in earnest at 11:15 (when about 3,000 were seen fairly deep within the bay still heading south in only thirty minutes). During the two timed counts at the headland, 3,780 went south in the first 20 minutes (when still largely overcast), with less than half of these coming out from the bay and the remainder taking a line that apparently originated from further north up the east coast. “Only” 1,530 were seen going south in the second timed 20 minutes (when the sun had finally broken through and the cloud cleared), with the majority of these apparently taking an increasingly distant line off from shore.
Although c. 20,000 Ancient Murrlet were counted during the day the number of birds seen and the movement itself was likely to have been much larger (30,000-40,000?). It is likely that there was substantial movement from at least dawn until dusk as we saw lines of flying murrelets throughout the day. Based on the counts that were made, there were hundreds or perhaps low thousands an hour on the move before 11AM; perhaps 6,000 an hour moving south between 11AM and 2PM (with this number in reality likely to have been much higher, as it was based on counts of birds within the bay, excluding birds moving over the sea outside of it); 10,000 an hour moving south between 2PM and 3PM; and low thousands or perhaps only hundreds an hour between 3PM and 5PM. Allowing for likely large-scale double-counting as well as birds likely missed gives a reasonable but still conservative estimate of 28,000 for the day.
In addition to some shorebirds (Dunlin and baueri Bar-tailed Godwit) and Aleutian Terns, we now know that some (many?) of the Ancient Murrelet that breed in parts of North America winter in East Asia; and that many of the Red-throated and Yellow-billed Loons that breed on the North Slope of Alaska also migrate to this region, where they pick up higher levels of PCBs and Mercury than others of the same species that winter within the Americas. There has been much international collaboration within the Americas for bird conservation but very little between the Americas and East Asia. Research into the abundance, distribution and conservation status of North American breeding birds and their habitats within East Asia really should be very much higher on the radar of North American conservation organisations than they have been to date.
- Least Auklet 작은바다오리. One or perhaps two (NM only) were seen, presumably caught up in the movement of Ancients.
- Rhinoceros Auklet 흰수염바다오리. A total of 51 were counted on the water and 466 were counted going south, suggesting about 700 an hour were moving south off the headland in the mid-late afternoon.
There were fewer gulls than usual, with only four Glaucous and several hundred Slaty-backed and Vega Gull seen. However, at each good gull spot, we saw birds flushed by people (with at one spot a few middle-aged gentlemen displaying their masculinity to their loving female companions by throwing stones at the gulls in order to make them fly – a courtship display incidentally which seemed far less impressive than that of the Harlequin Ducks; and others just wading through the gull roosts right in front of us to start fishing).
A few interesting looking birds (several of which were not seen well enough to consider all ageing and ID options because of the disturbance) are shown below.
First-winter Slaty-backed Gull © Nial Moores. This is most likely a pale-end individual or perhaps one with some hybrid influence (suggested to me at least by the extent of white along the primary edges; the extent of white in the tail; and the hint of greyish wash on the breast sides, apparently unusual in such a pale-looking individual).
Slaty-backed Gull © Nial Moores. The age is suggested as a “retarded Second-Cycle” by what seems to be a highly unusual combination for this species of solidly dark wing coverts and heavily mottled underparts; blackish primaries and scattered dark grey “adult-type” feathers on the scapulars and mantle; and obviously pale eye.
Presumed First-winter American Herring Gull Larus smithsonianus © Nial Moores. Although not seen in flight, ID was suggested by very extensively dark-looking tail; contrast between the white head and the (warm) brown upperparts; and the bill pattern.