56Wildlife Conservation Plan for Seabirds

56 Wildlife Conservation Plan for Seabirds

Matsudaira’s Storm-petrel (Hydrobates matsudairae)

TABLE Species information for Matsudaira's Storm-petrel

The Matsudaira’s Storm-petrel (Hyrobates matsudairae) is a dark-brown storm-petrel with long angular wings. Tail is long and forked. The species occupies a small

breeding range in southern Japan, probably only two islands. It is known to breed on Minami-Iwo-Jima, and perhaps on Kita-Iwo-Jima. It has also been recorded around Ogasawara Islands and it is assumed to breed there but required confirmation. The species is a colonial breeder, nesting in burrows on high ground. Breeding is thought to begin in January, with most young fledging by June. After the breeding season, birds move south to the Timor Sea, north-west Australia and into the northern Indian Ocean. During the non-breeding season Matsudaira’s Storm-petrel remains in oceanic waters far from the coast.

No quantitative data are available on the species population, although it is reported to be locally common in its breeding range and its abundance in the Indian Ocean has led to the suggestion that the global population is at least 20,000 individuals. The population trend is difficult to determine because of uncertainty over the main threats to the species. The species has been assessed as globally vulnerable under IUCN criteria on the basis that it occupies a small range when breeding and is susceptible to stochastic events and human impacts.

Black Rats (Rattus rattus) became established on Kita-Iwo-Jima apparently following the Second World War and are considered to have caused local extirpations. There does not appear to be any recent breeding records from the island. Rats pose a threat to birds attempting to recolonise the island. A greater threat would be the introduction of rats to the only known breeding island, Minami-Iwo-Jima. Storm-petrels are known to be vulnerable to oil pollution at sea and marine debris.

 Gain an improved understanding of at sea distribution in north west Australia

 Exchange information on successful Rattus spp. eradiation techniques with Japanese authorities

 Facilitate the collaboration between Australian and Japanese researchers to survey and monitor known colonies, study ecological requirements, search for undocumented breeding colonies in suitable habitat

Wildlife Conservation Plan for Seabirds 57

Swinhoe’s Storm-petrel (Hydrobates monorhis)

TABLE Species information for the Swinhoe's Storm-petrel (Hydrobates monorhis)

Swinhoe’s Storm-petrel (Hydrobates monorhis) is a small dark brown seabird that has a fluttering flight. The species can be found over oceanic and inshore waters. The species breeds on islands in the north-west Pacific Ocean off Russia, Japan, the Republic of Korea and China. Breeding starts in April forming loose colonies close to the sea in rock crevices and lays a single egg. The species is strictly nocturnal at the breeding sites to avoid predation by gulls and skuas. Outside the breeding season the species migrates into the Indian Ocean and Arabian Sea.