Data Zone
Justification of Red List category
Although the species has a restricted breeding range, it is not believed to 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). The population trend is stable, and hence does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is considered to be 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.
Population justification
More than 99% of the global population now breeds on Lord Howe Island, where approximately 32,000 pairs nest on Mt Gower and Mt Lidgbird with some additional birds nesting on the lower slopes and Northern Hills (Bester 2003). A small but increasing (c.250 pairs in 2016) population now breeds on Phillip Island after their discovery in the 1980s (Hermes et al. 1986, Carlile et al. 2021). Overall, the contemporary population is estimated to number 66,500-100,000 mature individuals, with a best estimate, from Carlile et al. (2021), of 83,000. Historically, a population on Norfolk Island was thought to have numbered about a million pairs in the late 18th century (Medway 2002) and was probably even larger 600 years earlier, before the arrival of Polynesian settlers (Lombal et al. 2017).
Trend justification
The population trend of this species is inferred to be stable (Carlile et al. 2021) in the absence of plausible threats causing declines. Surveys have determined that the species's distribution is likely to have increased since the eradication of pigs on Lord Howe Island and it appears to be establishing itself in the lower elevations south of Mt Lidgbird (Bester 2003). The population on Phillip Island has increased from about 20 pairs in 1985 when discovered (Priddel et al. 2010), to 250 pairs in 2016. Overall therefore the population appears to be stable (Carlile et al. 2021).
More than 99% of the global population of Providence Petrels breed on Lord Howe Island in the Tasman Sea, Australia, having been extirpated from the Norfolk Island group in the early 1800s (Medway 2002). A small but increasing population (~250 pairs in 2016) now breeds on Phillip Island in the Norfolk Island group after their discovery in the 1980s (Hermes et al. 1986). Birds are present at both breeding islands from March to November annually and often forage off eastern Australia (Bester et al. 2002, N. Carlile and T. O'Dwyer unpublished, in Carlile et al. 2021). Its non-breeding distribution is across the western Tasman Sea with some dispersing to the north and northwest Pacific Ocean, perhaps as far north as the Bering Sea (Marchant and Higgins 1990, Carlile et al. 2021).
It nests in burrows or under rock cavities and occasionally between tree buttresses from sea level to 900 m, but mostly between 500 and 800 m (Bester et al. 2002, Bester 2003). On Lord Howe, it breeds in forest, as once did the population of Norfolk Island, so the Phillip Island population is atypical, with burrows being in eroded cliffs of soft volcanic tuff (Priddel et al. 2010). It is a winter breeder, with birds from Phillip Island breeding at the same time as Lord Howe Island (Priddel et al. 2010). Adults arrive at Phillip from mid-April, a single egg is laid mid- to late May, hatching starts mid-July, and chicks are near-fledged by early November (Bester et al. 2007, Priddel et al. 2010). Adults land during daylight, often about 15.30 h (Priddel et al. 2010). A study on Lord Howe Island in 2000-2001 determined 54% breeding success in burrows visited twice and contents not handled, with 34-36% success in burrows repeatedly visited (Bester et al. 2007). Nests closest to burrow entrances had lowest breeding success, with the main causes of failure being flooding and predation of eggs and chicks by the endemic, threatened Lord Howe Woodhen Hypotaenidia sylvestris (Bester et al. 2007). A study in 2008 on Lord Howe Island found the breeding success in a small lowlands population to be three times higher (58%; n = 104) than in populations on Mount Gower (15%; n = 33) (D. Binder unpublished data). Additionally, adult provisioning trips were between 2–12 days (mean 4.8), with no evidence of a bimodal distribution of long and short trips (Binder et al. 2013). The adults feed predominantly on squid and fish with crustaceans less important. The most important prey item is bioluminescent fish from the genus Electrona; maximum diving depths have been recorded at 5 m (Bester 2003). It also scavenges for food taking fish offal and has been recorded scavenging on a Shining Bronze-cuckoo Chalcites lucidus (Bester 2003). It only occasionally follows fishing boats (Kuroda 1955, Bester 2003), but some fishing material has been reported in their diet (Bester 2003).
There are currently no plausible threats to the population on Lord Howe Island. On Phillip Island, Wedge-tailed Shearwater Ardenna pacifica sometimes evict young Providence Petrels from burrows (Priddel et al. 2010), and Purple Swamphens Porphyio porphyrio probably take some individuals (Priddel et al. 2010). The petrels were extirpated from Norfolk Island in the early 1800s as a result of feral pig Sus scrofa predation and hunting (Medway 2002), with pigs probably preventing the species from successfully nesting below the mountain summits on Lord Howe Island (Hull 1909). Wild pigs, cats and goats have been successfully eradicated from Lord Howe Island. Providence Petrels appear to have been unaffected by Black rats Rattus rattus which proliferated on Lord Howe Island after introduction in 1918 (McCulloch 1921). If rat eradication does occur, introduced masked owls Tyto novaehollandiae may switch to preying on petrels, potentially causing problematic declines (Bester et al. 2007); for this reason it has been proposed to subsequently eradicate the species (Walsh et al. 2019). Currently, the main causes of nest failure in the southern mountains are inundation of burrows and predation of eggs and chicks by Lord Howe Woodhens Hypotaenidia sylvestris, but neither of these threats is significant (Bester et al. 2002). Eradication of pigs and cats Felis catus on Lord Howe in the 1980s (McAllan et al. 2004) enabled spread of the species, with birds breeding beyond the southern mountains (Lombal et al. 2017). The species is considered to be of medium risk from longline fishing in the western and central Pacific (Waugh et al. 2012), but there is no direct evidence of capture or empirical evidence of population decline. Hunting is known to have severely affected the Norfolk Island population in the past, possibly causing its extirpation (Medway 2002), but is thought to be unlikely to return. Plastic ingestion may also represent a threat, with plastic found in the stomachs of over 10% of the birds sampled (Bester et al. 2010), however, this is not known to have any adverse consequences. Climate change may pose a future threat to the species (Rodríguez et al. 2019).
Conservation Actions Underway
The Lord Howe Island group was designated a World Heritage Site in 1982. Control of rats has been an ongoing process on Lord Howe. An initial eradication was locally successful (see Bester et al. 2007) and a widespread $16 m eradication programme began in winter 2019. Although initially thought to be successful, two rats were detected and killed in 2021, although these were suspected to be incursions from the mainland rather than survivors of the eradication (Lord How Island Board in litt. 2021). In 2006, a proposal was submitted to eradicate all mammalian predators from all, or at least a significant part, of Norfolk Island (Holdaway 1999). Such measures might involve the establishment of an exclosure in the National Park in which all mammals are eliminated, and where chicks are translocated (Holdaway 1999, S. Garnett in litt. 2006). The small colony on Phillip Island is surveyed irregularly and monitoring of the main Lord Howe island population has occurred as part of research projects (Carlile et al. 2021).Conservation Actions Proposed
Census the Lord Howe Island population at least once every five years, and the Phillip Island population every three years. Monitor breeding success on a 1-3 year basis. Eradicate cats and rat species from Norfolk Island (Holdaway 1999), or at least establish an exclusion area (Holdaway 1999, S. Garnett in litt. 2006). Consider translocation of chicks (Holdaway 1999, S. Garnett in litt. 2006). Implement bird-safe fishing practices in the Pacific Ocean fleet. Impose strict quarantine procedures on any vessels visiting Phillip Island and Lord Howe Island.
40 cm. Medium-sized, all-dark gadfly petrel. Uniform, fairly dark grey-brown with extensive whitish scaling around face and on chin, and white skua-like base to primaries on underwing. Sexually dimorphic. Males larger with significantly longer culmen (Bester et al. in press). Similar spp. Relatively long, wedge-shaped tail useful character when visible. Murphy's Petrel P. ultima has more slender bill, whiter throat, and stronger traces of "M" pattern on upperwing. Even darkest Kermadec Petrel P. neglecta has white primary shafts on upperwing. Grey-faced Petrel P. macroptera gouldi has similar face pattern, but is darker.
Text account compilers
Garnett, S., Fjagesund, T., Hermes, C., Martin, R., Anderson, O., Taylor, J., Vine, J., Stuart, A., Moreno, R., McClellan, R., Stattersfield, A.
Contributors
Binder, D., Carlile, N., Garnett, S. & Hobbs, J.
Recommended citation
BirdLife International (2024) Species factsheet: Providence Petrel Pterodroma solandri. Downloaded from
https://datazone.birdlife.org/species/factsheet/providence-petrel-pterodroma-solandri on 22/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 22/11/2024.