Crested murrelet  (Synthliboramphus wumizusume)

The crested murrelet is classified as Vulnerable (VU) on the IUCN Red List 2007 (1) and is listed on Appendix I of the Convention on Migratory Species (CMS or Bonn Convention) (3).

A small, plump bird, the crested murrelet has black and bluish-grey upperparts, fading to greyish flanks and a white throat and underparts. During the summer, the feathers of the head and the crest darken to black, and white stripes run from the top of the eyes to the nape of the neck. This species has yellow-grey feet and legs. Juveniles are browner than adults (2).

Breeding on uninhabited islands off the southern coasts of Japan and South Korea, the crested murrelet enjoys the warm climate of this area, which is created by the Kuroshio Current. In the non-breeding season, the crested murrelet migrates to the northernmost islands of Japan (2).

This species breeds on rocky islets and headlands, foraging in offshore waters. In winter, it is more pelagic, spending much of the time far from land (2).

Built for swimming and diving, the crested murrelet has short wings that it must flap rapidly in order to stay airborne (4). It feeds on small fish and zooplankton just beneath the water surface (5).

This auk species nests in pairs, small groups and even large colonies (2) scratching a shallow depression in the ground for egg-laying (5). The breeding season varies with location, but is usually between mid February and early May. The female lays two eggs, the second a week after the first, and these hatch after 34 days of incubation (5).

The crested murrelet faces a large number of threats from many sources. It is preyed upon by the introduced black rat (Rattus rattus), and by gulls and crows that are attracted to the islands by waste from fishing operations. Drift nets are known to cause high adult mortality, and sport fishing contributes to disturbance and habitat degradation, reducing breeding success. It is also possible that fish stocks in the area are declining due to changes in water temperature (2).

Protected in Japan, several of the breeding sites of the crested murrelet are also designated as National Wildlife Protection Areas. Gugul Islet, South Korea, which is home to this species, has been designated as a Natural Monument. In Japan a leaflet has been produced to inform fishermen of the plight of the crested murrelet, but ideally, sport fishing needs to be prevented at crested murrelet breeding sites and drift nets should be re-designed to reduce by-catch (2).

View information on this species at the UNEP World Conservation Monitoring Centre.

For further information on the crested murrelet see:

• BirdLife International. (2001) Threatened Birds of Asia: the BirdLife International Red Data Book. BirdLife International, Cambridge, UK.