Charadriiformes / Laridae / Saundersilarus
Saunders's Gull
Saundersilarus saundersi · 黑嘴鸥
Introduction
A species of gull in the family Laridae, currently placed in the monotypic genus Saundersilarus. It inhabits estuarine waters and intertidal marshes across East Asia. The species is threatened by habitat loss and is assessed as Vulnerable.
Description
A very small gull with a body length of 33 cm (13 in). Adults display a black hood and nape during the breeding season, with a white body and tail, and pale grey wings. Non-breeding birds have a mottled grey hood and nape, with white-tipped wings showing black markings on the primaries. Immatures are distinguished by a narrow black tail band and dark mottling on the upperwing. The legs are dark red-brown, the short bill is black, and the body shape is squat.
Identification
Among gulls, only the little gull is smaller. Key identification features include the black hood in breeding plumage, mottled grey hood in non-breeding plumage, and the narrow black tail band in immatures. The species has partially webbed feet and a distinctive squat posture.
Distribution & Habitat
Breeds in eastern China and the west coast of Korea in saltmarshes dominated by Suaeda glauca. Overwinters in southern China, Hong Kong, Macau, Taiwan, South Korea, southwestern Japan, and Vietnam. Winter habitats include estuaries, aquaculture ponds, lakes, and marshes.
Behavior & Ecology
Forages by flying approximately 10 meters above the ground and dropping swiftly to catch mudskippers, crabs, fish, and worms. It also acts as a kleptoparasite, stealing food from other birds. A poor swimmer due to partially webbed feet, it typically stays on land, moving up the beach ahead of rising tides. Breeding occurs in saltmarshes with simple ground scrape nests. The species is monogamous, territorial, and lays two or three eggs in May. Incubation lasts about 22 days. Adults and young migrate to winter quarters in October.
Conservation
Assessed as Vulnerable by the IUCN. The total population is estimated at 14,400 individuals, though some estimates range from 7,100 to 9,600, with a declining trend. Major threats include habitat loss from the conversion of saltmarshes to agricultural land, fish farms, and industrial development such as oil extraction. The introduction of Spartina alterniflora (smooth cord-grass) negatively impacts habitat quality. Disturbance of adults leads to increased predation on eggs and chicks. The Yancheng Coastal Wetlands host about 20% of the global population.
Source: Wikipedia · CC BY-SA 3.0
Taxonomy
- Order
- Charadriiformes
- Family
- Laridae
- Genus
- Saundersilarus
Taxonomy Changes
Chroicocephalus saundersi → Saundersilarus saundersi
Genus transfer — GBIF Backbone Taxonomy uses the former name; AviList 2025 uses the current name.
Distribution
breeds Yellow Sea coasts from Liaoning to Jiangsu (eastern China) and Songdo (northwestern South Korea); winters coasts of East China Sea from Japan and Korean Peninsula to northern Vietnam
Data Sources
CBR Notes: 由Chroicocephalus属移入Saundersilarus属（Pons et al. 2005; Černý and Natale 2022）
Species description from Wikipedia, licensed under CC BY-SA 3.0.
Bird images and sounds sourced from GBIF, contributed by citizen scientists worldwide under Creative Commons licenses.
Taxonomy data from AviList 2025.
