Abstract
The Brown-headed Gull (BHGU) Chroicocephalus brunnicephalus is a common non-breeding migrant to Sri Lanka's coasts. However, its migration across the Central Asian Flyway—traversing numerous geographic barriers such as the Himalayas and the Tibetan Plateau to reach the southern Indian peninsula and Sri Lanka—has not been studied. We GPS-tracked two BHGUs between Sri Lanka and their breeding grounds on the Tibetan Plateau from 2021 to 2023, documenting four migrations in total—three northward and one southward. During northward migration (25 April-20 May), the gulls covered 2,786.7 ± 168.0 km in 6.8 ± 1.05 d without any stopovers, although they made several rest stops (< 48 h each), including along the Ganges River in northern India. BHGU1 remained on the Tibetan Plateau for 157 d; BHGU2's duration of stay is unknown due to a temporary device failure. Southward migration occurred between 06 October and 19 December, with BHGU2's migration taking > 31 d, including two stopovers totaling 13 d along India's west coast. Notably, both gulls followed India's east coast during northward migration, whereas BHGU2 followed the west coast southward, indicating a loop migration pattern. The gulls crossed the Himalayas at ground elevations of 3,568-6,003 m above sea level, navigating three main regions: Annapurna, Khumbu/Everest, and Kanchenjunga. They often used valleys and gorges such as the Marsyangdi Valley, Kali Gandaki Gorge, and Dudh Koshi River, although they also occasionally flew over or near the main Himalayan peaks. Our findings reveal new insights into the extreme altitudes reached by migrating BHGUs, both while crossing the Himalayas and flying over inland India, even in the absence of topographic constraints. Further tagging of this non-breeding population is needed to explore potential age- or sex-related variation in migratory strategies, and to understand how this relatively small species (372.5 ± 53.0 g) manages high-altitude migration—a trait previously studied primarily in larger birds.
DOI
http://doi.org/10.5038/2074-1235.53.2.1660
Creative Commons License
Recommended Citation
Panagoda, Gayomini; Wijethunge, Iromi K.; Zhang, Beixi; Meng, Fanjuan; Chen, Yiwen; Kotagama, Sarath; Mundkur, Taej; Balachandran, Sivananinthaperumal; Cao, Lei; and Seneviratne, Sampath S.
(2025)
"From Tropical Shores to High-Altitude Lakes: Preliminary Assessment of Trans-Himalayan Migration of Brown-Headed Gulls Chroicocephalus brunnicephalus between Sri Lanka and the Tibetan Plateau,"
Marine Ornithology: Vol. 53
:
Iss.
2
, Article 20.
http://doi.org/10.5038/2074-1235.53.2.1660
Available at:
https://digitalcommons.usf.edu/marine_ornithology/vol53/iss2/20