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Bounty Islands Shag Phalacrocorax ranfurlyi

Justification
This species is classified as Vulnerable because it has a very small population and breeding range, rendering it susceptible to stochastic events and human impacts. If population fluctuations are shown to be extreme, or if there is any population decline, it may warrant uplisting to Critically Endangered.

Taxonomic source(s)
Sibley, C. G.; Monroe, B. L. 1990. Distribution and taxonomy of birds of the world. Yale University Press, New Haven, USA.
Turbott, E. G. 1990. Checklist of the birds of New Zealand. Ornithological Society of New Zealand, Wellington.

Synonym(s)
Leucocarbo ranfurlyi Turbott (1990), Leucocarbo ranfurlyi ranfurlyi Turbott (1990)

Identification
71 cm. Large, black-and-white cormorant. Black head, hind neck, lower back, rump, uppertail-coverts, all with metallic blue sheen. White underparts. Pink feet. White patches on wings appear as bar when folded. Caruncles absent. Voice Male makes call during displays only.

Distribution and population
Phalacrocorax ranfurlyi is restricted to the Bounty Islands, New Zealand. In 1978, 569 pairs were observed on 11 islands (Robertson and van Tets 1982). In 1997, a repeat census was attempted, but proved very difficult because it was not possible to land on the islands. However, colonies were noted on 13 islands, and 120 nests and 368 birds were counted (A. M. Booth in litt 1998). The islands were surveyed again from land in 2005, when 618 individuals were counted (R. Hitchmough in litt. 2005). Although it is not known whether differences in the estimates are due to differing survey methods, differences in peak breeding times between years or a true change in numbers, a comparison with other species surveyed at the same time suggests that they show genuine trends (Taylor 2000, R. Hitchmough in litt. 2005). Surveys in 2011 suggest that the overall population has remained stable since 2005 (J. Hiscock in litt. 2012). The population is likely to fluctuate markedly as a result of the effects of weather conditions on feeding (A. J. D. Tennyson in litt. 1994). The species's foraging range is assumed to be up to 24 km offshore (cf. New Zealand King Shag P. carunculatus).

Population justification
The population is estimated to number at least 620 individuals, roughly equating to 410 mature individuals (R. Hitchmough in litt. 2005).

Trend justification
Boat-based surveys conducted in 2011 suggest that numbers were similar to those counted in 2005 (J. Hiscock in litt. 2012), probably indicating that the population is stable overall.


Ecology
It breeds mostly on narrow cliff-side ledges, with nests often as little as 1 m apart (Robertson and van Tets 1982, Heather and Robertson 1997). It feeds on fish, snails, squid, isopods and crabs (Robertson and van Tets 1982).

Threats
Extreme weather conditions may be a threat (A. J. D. Tennyson in litt. 1994). Nesting sites may be restricted by the presence of large numbers of fur seal Arctocephalus forsteri, Salvin's Albatross Thalassarche salvini and Erect-crested Penguin Eudyptes sclateri (Marchant and Higgins 1990). The introduction of mammalian predators is very unlikely, but remains a possibility. The most likely long-term threat to the species is posed by changes to the marine environment around the islands, possibly driven by climate change.

Conservation Actions Underway
The Bounty Islands are nature reserves and are free of introduced predators. In 1998, they were declared part of a World Heritage Site. Conservation Actions Proposed
Complete a full census of all colonies every 10 years, including a census of nest-sites and breeding pairs (A. D. Roberts in litt. 1999, Taylor 2000). Turn the World Heritage Site territorial sea (out to 12 nautical miles) into a marine reserve and restrict all fishing (B. Weeber in litt. 2000).

References
Heather, B. D.; Robertson, H. A. 1997. The field guide to the birds of New Zealand. Oxford University Press, Oxford, UK.

Marchant, S.; Higgins, P. J. 1990. Handbook of Australian, New Zealand and Antarctic birds, 1: ratites to ducks. Oxford University Press, Melbourne.

Robertson, C. J. R.; van Tets, G. F. 1982. The status of birds at the Bounty Islands. Notornis 29: 311-336.

Taylor, G. A. 2000. Action plan for seabird conservation in New Zealand. Department of Conservation, Wellington.

Text account compilers
Benstead, P., Mahood, S., McClellan, R., Pilgrim, J., Taylor, J.

Contributors
Booth, A., Hiscock, J., Moore, P., Roberts, A., Taylor, G., Tennyson, A., Weeber, B.

IUCN Red List evaluators
Butchart, S., Symes, A.

Recommended citation
BirdLife International (2014) Species factsheet: Phalacrocorax ranfurlyi. Downloaded from http://www.birdlife.org on 16/04/2014. Recommended citation for factsheets for more than one species: BirdLife International (2014) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 16/04/2014.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.

Additional resources for this species

ARKive species - Bounty Islands Shag (Phalacrocorax ranfurlyi) 0

Key facts
Current IUCN Red List category Vulnerable
Family Phalacrocoracidae (Cormorants)
Species name author Ogilvie-Grant, 1901
Population size 410 mature individuals
Population trend Stable
Distribution size (breeding/resident) 1 km2
Country endemic? Yes
Links to further information
- Additional Information on this species