Phalacrocorax featherstoni
| Kingdom |
Phylum |
Class |
Order |
Family |
| ANIMALIA |
CHORDATA |
AVES |
PELECANIFORMES |
PHALACROCORACIDAE |
| Scientific Name: |
Phalacrocorax featherstoni |
| Species Authority: |
Buller, 1873 |
Common Name/s:
| English |
– |
Pitt Island Shag |
|
Assessment Information
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| Red List Category & Criteria: |
Endangered
C1
ver 3.1
|
| Year Published: |
2010 |
| Assessor/s: |
BirdLife International |
| Reviewer/s: |
Calvert, R., Butchart, S., Bird, J. |
| Contributor/s: |
Weeber, B., Bester, A., Hitchmough, R., Bell, B. |
Justification:
This species is listed as Endangered because it has a very small population which has declined moderately rapidly over the last two generations (18 years), a decline which is predicted to continue given current threats.
|
| History: |
| 2008 |
– |
Endangered
|
| 2006 |
– |
Endangered
|
| 2005 |
– |
Endangered
|
| 2004 |
– |
Vulnerable
|
| 2000 |
– |
Vulnerable
|
| 1996 |
– |
Vulnerable
|
| 1994 |
– |
Vulnerable
|
|
Geographic Range
[top]
| Range Description: |
Phalacrocorax featherstoni is found in the Chatham Islands, New Zealand, on Chatham, Pitt, Mangere, Little Mangere, South East (= Rangatira), Star Keys, the Pyramid, Big and Middle Sister, Murumurus, the Castle and Rabbit Islands3,4,5. The population has been variously estimated at c.500 pairs, less than 1,000 pairs2 and, in 1997-98, at 729 pairs following a complete census over the entire breeding range7. However, new information suggests that the population has declined by 25% over six years from 1997 to 2003, with 547 pairs counted in the second complete census over the 2003-2004 breeding season9. Feeding range is assumed to be 24 km (cf. New Zealand King Shag P. carunculatus).
|
| Countries: |
Native:
New Zealand; United States
|
| Range Map: |
Click here to open the map viewer and explore range.
|
Population
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| Population: |
A total of 547 pairs (=1,094 mature individuals; 1,400 estimated total individuals) were counted in the second complete census over the 2003-2004 breeding season (Bester and Charteris 2005).
|
| Population Trend: |
Decreasing
|
Habitat and Ecology
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| Habitat and Ecology: |
It nests in small colonies of between five and 20 pairs, on rocky shores and islets, headlands and cliffs. Breeding distribution is limited by suitable nesting sites4. It feeds primarily on small fish, supplemented by marine invertebrates2.
|
| Systems: |
Terrestrial; Marine |
| Major Threat(s): |
The effects of introduced species on Chatham and Pitt Islands are not known, with birds tending to nest in inaccessible sites. Some nests, however, could be affected by stock, feral cats, pigs, dogs, black rat Rattus rattus, brown rat R. norvegicus and Weka Gallirallus australis5. Birds are sometimes illegally shot by fishermen2,5. A total of 40-80 birds may be caught in crayfish pots annually7. Recent declines may be a response to changes in the marine environment that are affecting food supplies9. The species is potentially threatened by climate change because it has a geographically bounded distribution: it is restricted to an island or islands with a maximum altitude of 283 m10.
|
Conservation Actions
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| Conservation Actions: |
Conservation Actions Underway
In 1961, sheep and cattle were removed from South East Island and, in 1968, sheep were taken off Mangere Island5.
Conservation Actions Proposed
Census entire adult population once a suitable methodology has been developed, and at 10-year intervals thereafter. Monitor two accessible colonies annually to determine trends5. Assess impact of rock lobster fishing practices6. Remove feral cats and G. australis from Pitt Island if agreement is reached with residents. Remove sheep, cattle and pigs from parts of Pitt and Chatham Islands that are suitable for colonies. Fence colonies (with owners' permission) if stock are found to be impacting on colonies5.
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