|Red List Category & Criteria:
||Butchart, S. & Symes, A.
||Butchart, S., Calvert, R., Ekstrom, J. & Newton, P.
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
|Previously published Red List assessments:|
- 2016 – Least Concern (LC)
- 2012 – Least Concern (LC)
- 2009 – Least Concern (LC)
- 2008 – Least Concern (LC)
- 2004 – Least Concern (LC)
- 2000 – Lower Risk/least concern (LR/lc)
- 1994 – Lower Risk/least concern (LR/lc)
- 1988 – Lower Risk/least concern (LR/lc)
|Range Description:||This species breeds on Tasmania and off the coast of south Australia, with the bulk of the population in the south-east. It undergoes transequatorial migration, wintering north of Japan near the Aleutian Islands (USA), with some moving north of the Bering Strait. The return migration route incorporates the central Pacific, with some moving down the western coast of North America. |
Antarctica; Australia; Canada; Costa Rica; Fiji; Guam; India; Japan; Korea, Republic of; Marshall Islands; Mexico; Micronesia, Federated States of ; New Zealand; Northern Mariana Islands; Russian Federation (Eastern Asian Russia); Solomon Islands; Sri Lanka; United States
Present - origin uncertain:
American Samoa; Cook Islands; French Polynesia; Kiribati; Nauru; New Caledonia; Niue; Norfolk Island; Papua New Guinea; Pitcairn; Samoa; Tokelau; Tonga; Tuvalu; United States Minor Outlying Islands; Vanuatu; Wallis and Futuna
|♦ Continuing decline in area of occupancy (AOO):||Unknown|
|♦ Extreme fluctuations in area of occupancy (AOO):||No||♦ Estimated extent of occurrence (EOO) - km2:||155000000|
|♦ Continuing decline in extent of occurrence (EOO):||Unknown||♦ Extreme fluctuations in extent of occurrence (EOO):||No|
|♦ Continuing decline in number of locations:||Unknown|
|♦ Extreme fluctuations in the number of locations:||No|
|Range Map:||Click here to open the map viewer and explore range.|