Bird News by Leslie Hurteau (Birds Korea member and eBird Reviewer for Jeju)
On March 5th, 2023, Thilinda Shiraj and I were birdwatching in Seogwipo Harbour area, on the south side of Jeju Island. While scanning through a group of Black-tailed Gulls Larus crassirostris, one gull stood out: a smaller species with a red bill and legs, and faint black spotting on the head. Assuming this was simply a Black-headed Gull Chroicocephalus ridibundus, an uncommon visitor to Jeju but quite common on the mainland, we snapped a few photos and moved on. Later on in the evening, when reviewing the photos, I noticed that this gull had clear-looking eyes, and the wingtips were all black. I didn’t think too much of it at first, but realised that they were strange features.
Later the same evening, I also looked through bird news from Japan (on the Kantori Facebook group), and read that a Brown-headed Gull Chroicocephalus brunnicephalus, a vagrant to Japan with only two published records up to 2020, had been seen in a harbour near Tokyo just the day before (March 4th). The images made me realize I should check my photos more closely – so I promptly took out my copy of Gulls of the World (by Klaus Malling Olsen, an excellent photo ID book of gulls) to compare his images with those of “the gull”. The pale irides began to make sense as I looked at the section on Brown-headed Gull. Looking closer still at my photos, I started to notice different proportions from those expected in Black-headed Gull, such as the bill looking larger than normal. Given that Brown-headed Gull was not on any Korean national checklist, I decided it was best to get some second opinions before I started making what could easily be seen as wild claims by the birding community.
I messaged Dr. Nial Moores (eBird reviewer and Birds Korea director), sending some of the photos and asking for his opinion. His responses supported my suspicions that this indeed looked like (was…) a Brown-headed Gull. Unfortunately, Mr. Shiraj and I didn’t get any flight photos, and due to the tricky nature of gull identification I decided it was worthwhile to take an early morning trip the next day before work (March 6th), to see if “the gull” was still around. To confirm identification, especially to rule out a hybrid, I knew I needed to get photos of the pattern on the spread wing. Luck was on my side as I found the gull straight away, this time just metres away, feeding on fish scraps by the Seogwipo Fish Distribution Centre, even allowing for video to be taken with my phone. In flight, the gull showed two “mirrors” on each wing tip: a diagnostic feature of Brown-headed Gull! I took more images, and my excitement continued to grow as I realised that we really had found a National First for Korea.
Once the identification was confirmed, I notified the Jeju Wildlife Research Center (제주야생동물연구센터), an island-based group of Jeju wildlife experts, researchers, and enthusiasts, to whom I regularly report sightings. They confirmed the fact that no-one else had reported the bird, and that they were also unaware of any previous records on Jeju or elsewhere in the ROK. Due to the high-profile nature of a National First, they advised and requested me to keep the sighting confidential while the gull remained in the harbour area. This was to prevent a commotion in an area which was already busy with both the fishing and tourism industries, as well as to allow for proper documentation of the gull and to prepare official press releases.
While I didn’t think the safety of this bird was a concern, I did agree that a crowd of birders turning up might have caused some potential issues with the local fisheries workers. In addition, suppressing information of rare birds is a somewhat regular practice in many birding communities, with information of rarities and sensitive species not widely shared until the bird has left. While I don’t necessarily agree with this approach, I do recognise that each birding community has its own culture, and I like to think this is usually done with the best interest of the birds. So, (unfortunately) news about this gull was kept quiet until after its final sighting on March 12th. Potential Korean names were discussed, and as of now the species has been tentatively named 갈색머리갈매기. This is a direct translation of Brown-headed Gull, “갈색” being brown colour, “머리” being head, and “갈매기” being the general word for gull in Korean. Several news reports were released on March 16th and 17th, some of which can be seen here:
https://n.news.naver.com/article/003/0011745600?sid=102
This sighting is important in several ways. This being the first record for the ROK is important to the national birding and scientific communities, and any adequately-documented record of a species in a new area is important to researchers and birders both nationally and regionally. The finding can contribute to current scientific knowledge of species distribution, and help connect to broader subjects such as climate change and range expansion.
Bottom: A distribution map showing sightings from January-April 2023. During this period, individual Brown-headed Gulls were recorded in Japan, Korea, and Eastern China (in the Shanghai region). The dates of the records fall within a broadly similar time frame (Tokyo: Mar 4 – 11, Jeju: Mar 5 – 6, and China: Feb 28 (Jiangsu), Mar 23 – 25 (Zhejiang). Is the timing of these findings a coincidence, or was there a weather event that brought Brown-headed Gulls further east of their normal range?
Second, a record of Brown-headed Gull in Korea helps to fill in a gap in the mapped distribution range. In the context of records as far east as Tokyo, Japan, as well as along the Chinese Yellow Sea coast, it’s not unexpected that a Brown-headed Gull would be found in Korea. In fact, some people were waiting for the day! And Jeju does seem like a good place to find such species, given their predominantly tropical / subtropical wintering range. It also seems quite likely that this species will have shown up in Korea before, unnoticed. How many birdwatchers (not just in Korea, but worldwide) are willing to put in the time to sort through piles of gulls littered across cold windy coastlines in winter? I hope that this discovery encourages other birders to look through groups of gulls and become more familiar with the expected and regularly occurring species. With more eyes on the look out, it’s possible more new species for Korea will be found, particularly species from Western North America and Central Asia.
