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Christmas Island Frigatebird Fregata andrewsi
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This species has a small population which breeds within a tiny Area of Occupancy on just one island, and which is continuing to decline. For these reasons it is listed as Critically Endangered.

Taxonomic source(s)
Christidis, L.; Boles, W. E. 1994. The taxonomy and species of birds of Australia and its territories. Royal Australasian Ornithologists' Union, Melbourne.
Christidis, L.; Boles, W. E. 2008. Systematics and taxonomy of Australian birds. CSIRO Publishing, Collingwood, Australia.
Dowsett, R. J.; Forbes-Watson, A. D. 1993. Checklist of birds of the Afrotropical and Malagasy regions. Tauraco Press, Li
Sibley, C. G.; Monroe, B. L. 1990. Distribution and taxonomy of birds of the world. Yale University Press, New Haven, USA.

90-100 cm. Huge, mostly black, fork-tailed seabird with white belly and pale bar on upperwings. Adult male has red gular pouch and small white belly patch; long, dark grey, hooked bill. Adult female has black head, throat and spur on sides of upper breast and white collar, breast, belly and spur onto axillaries. Pink bill and red orbital ring. Similar spp. Adult Great Frigatebird F. minor male has all black underparts. Female has dusky throat, black axillaries and lower belly. Adult Lesser Frigatebird F. ariel is smaller with black belly. Immature F. minor has shorter bill and tawny-white head (tawny-yellow in F. andrewsi). Immature F. ariel is smaller and tends to have dark belly. Juvenile F. andrewsi tends to have white lower belly and white spur on axillaries. See James (2004) for detailed notes on identifying frigatebirds.

Distribution and population
This species is endemic as a breeding species to Christmas Island (to Australia). In 2003 it was estimated that there were 1,171 (± 58) breeding pairs. The number of nests was probably between 3% and 16% lower in 2003 than 1985 (one generation; 1985 estimates ranging from 1,320-1,620 pairs [Stokes 1988]), but this may not be an accurate indication of population trends. Due to biennial breeding, the total breeding population is between one and two times the number of pairs nesting per annum (i.e. 1,200-2,400 pairs). An historical review of the extent and decline of the four sub-colonies suggests that the pre-settlement population was about 6,300 breeding pairs per annum, but declined to 4,500 by 1910, 3,500 by 1945, 2,500 by 1967, and 1,500 by 1978. If this reconstruction is correct, then the population declined by about 66% over three generations between 1945 and 2003 (James 2003). In 2003 there were four sub-colonies (since reduced to three) covering an area of c.49 ha (Stokes 1988, James 2003). The Flying Fish Cove sub-colony probably contained c.50 ha of habitat in 1887; it underwent an almost complete decline in the early 1900s, and in 2003 it contained only c.10 ha of habitat and two nests. The Dryers sub-colony underwent an almost complete decline by the 1970s, and in 2003 contained c.62 ha of habitat and 20 nests. The Golf Course sub-colony lost c.13 ha (25%) in the 1940s, and in 2003 it contained c.25 ha of habitat and an estimated 828 (± 42) nests. The Cemetery sub-colony contained 46 ha of habitat and an estimated 321 (± 15) nests in 2003 (James 2003). Surveys in 2004 showed a significant increase in number of nests, with 767 nests in 244 nest trees at the largest colony (James 2004b) but surveys in 2005 showed a return to 2003 levels, suggesting that inter-annual variation rather than population growth explains the increase in numbers in 2004. Breeding and non-breeding birds have been recorded foraging at low densities in the Indo-Malay Archipelago (James 2004) over the Sunda Shelf to the South China Sea, the Andaman Sea, the Sulu Sea, off south-west Sulawesi, and in the Gulf of Thailand (Catterral 1997, Vromant and Chau 2007, D. James in litt. 2007, Tebb et al. 2008), commuting directly over Java in the process (James 2006). When not breeding the species ranges widely across the seas of South-East Asia to Indochina and south to northern Australia (Stokes 1988), but its status in the Indian Ocean to the west is less well known.

Population justification
The most recent population census indicates a population of 2,400-4,800 mature individuals (D. James in litt. 2003), roughly equivalent to 3,600-7,200 individuals in total.

Trend justification
A historical review suggests that the population declined by around 66% over the last three generations (James 2003), apparently owing to habitat clearance and dust fallout from phosphate mining, marine pollution, over-fishing and bycatch in fishing gear. These declines are projected to continue, and while the introduced yellow crazy ant has not yet been shown to adversely affect frigatebird colonies it undoubtedly represents a serious future threat.

It nests in tall forest trees. Terminalia catappa and Celtis timorensis trees hold 65.5% of all nests (Hill and Dunn 2005).It is only capable of raising a maximum of one fledgling every two years. It forages for flying fish, squid and other marine creatures, and is largely dependent on subsurface predators to drive prey to the surface. Most food is captured by plucking it from the sea surface while on the wing, but it is also an accomplished aerial kleptoparasite. Evidence suggests that breeding birds frequently forage hundreds or even thousands of kilometres from the colony. Satellite tracking showed that one female with a large chick undertook a non-stop 26-day 4,000 km return flight from Christmas Island via Sumatra and Borneo (James 2006). Replacement rate of pairs is thought to be extremely slow (15-25 years) rendering the population slow to recover following declines (Hill and Dunn 2005).

About a quarter of the breeding area was cleared before 1946 for phosphate mining, and the Flying Fish Cove colony was largely deserted because of continuing dust fallout from phosphate dryers. Future habitat loss is possible through clearance for mining. A new application to mine a 250 ha area of rainforest (P. Green in litt. 2007) is currently under review. About two thirds of the nests are now located in a single colony, making the species vulnerable to cyclones. Poaching ceased in the 1980s. A possible threat is the introduced yellow crazy ant Anoplolepis gracilipes which formed super-colonies during the 1990s and spread rapidly to cover about 25% of the island or about 3,400 ha. Control measures have so far been unable to eradicate this non-native species, but to date frigatebirds have not apparently been adversely affected by them. However, ant super-colonies alter island ecology by killing the dominant life-form, the red crab Gecaroidea natalis, and by farming scale insects which damage the trees. This may alter the breeding habitat of the species in the medium- to long-term (Hennicke in litt. 2010). Less specific threats include over-fishing and marine pollution, plus clearance of vegetation and hunting on non-breeding roost islands (P. Green and D. O'Dowd in litt. 2003, S. Garnett in litt. 2003, James 2003, Jensen and Tan 2010). Approximately 10% of the population nests outside the national park and does not have any formal protection (Hill and Dunn 2005). Clearance of vegetation within 300 m of nesting colonies should be avoided (Hill and Dunn 2005). Frigatebirds are highly susceptible to entanglement in fishing gear, so intense fishing pressure in the South-East Asian waters and severe marine pollution there represent significant threats to the species (James 2006). Research is underway to establish whether a potentially new blood parasite poses a threat to the species (Hennicke in litt. 2010).

Conservation Actions Underway
CITES Appendix I. Listed as vulnerable under the Environment Protection and Biodiversity Conservation Act 1999 (Hill and Dunn 2005). The Christmas Island National Park was established in 1980, and has since been extended to include two of the three current breeding colonies (90% of the population) (P. Green and D. O'Dowd in litt. 2003). A recovery plan has been completed (Hill and Dunn 2005) and a study using satellite telemetry to study movements has been underway since 2005 (J. Hennicke in litt. 2008, 2010). A control programme for A. gracilipes was initiated after 2000, including aerial baiting in 2002, and effectively eliminated the ant from 2,800 ha of forest (95% of its former extent) (P. Green and D. O'Dowd in litt. 2003, Olsen 2005). However, the ant population continued to increase, covering upwards of 500 ha by 2006. Despite continued control efforts, ants remained persistent in 2009, and perpetual baiting may be the only means of controlling them (Olsen 2005). Efforts are underway to find alternative bait that is not toxic to invertebrates on the island (Olsen 2005). Plans have been established to control the scale bugs that the ants tend for their sugar secretions in order to reduce this food supply, but there remains no evidence that they are adversely affecting frigatebird colonies (Hennicke in litt. 2010). A census of Christmas Island was planned for April 2010 (Hennicke in litt. 2010). Conservation Actions Proposed
Implement the species recovery plan. Continue to control the abundance and spread of A. gracilipes. Develop and implement appropriate techniques to monitor the total/breeding population size and population structure (Hill and Dunn 2005). Analyse existing data on breeding biology and success. Lobby to prevent mining close to colonies. Negotiate protection of all known and potential nesting habitat and appropriate buffers. If necessary, implement appropriate management in feeding habitat in South-East Asia to avoid bycatch etc. Maintain a quarantine barrier between Christmas Island and other lands to minimise the risks of new avian diseases establishing (Hill and Dunn 2005).

Related state of the world's birds case studies

Catterrall, M. 1997. Bird survey report of Buton Island 1996-1997. Available at: #

Garnett, S. T.; Crowley, G. M. 2000. The action plan for Australian birds 2000. Environment Australia, Canberra.

Hill, R.; Dunn, A. 2004. National recovery plan for the Christmas Island Frigatebird Fregata andrewsi. Commonwealth of Australia, Canberra.

James, D. 2006. Secrets of Christmas seabird revealed. World Birdwatch 28(1).

James, D. J. 2003. A survey of Christmas Island Frigatebird nests in 2003.

James, D. J. 2004. Christmas Island biodiversity monitoring programme. Third Quarterly Report April-June 2004.

James, D.J. 2004. Identification of Christmas Island, Great and Lesser Frigatebirds. BirdingASIA: 22-38.

Stokes, T. 1988. A review of the birds of Christmas Island, Indian Ocean.

Tebb, G.; Morris, P.; Los, P. 2008. New and interesting bird records from Sulawesi and Halmahera, Indonesia. BirdingASIA: 67-76.

Vromant, N.; Nguyen Thi Hoai Chau. 2007. Christmas Island Frigatebird Fregata andrewsi: first confirmed observation for Vietnam. BirdingASIA 7: 88-89.

Further web sources of information
Alliance for Zero Extinction (AZE) species/site profile. This species has been identified as an AZE trigger due to its IUCN Red List status and limited range.

Australian Govt - Action Plan for Australian Birds 2000 - Recovery Outline

Detailed species accounts from the Threatened birds of Asia: the BirdLife International Red Data Book (BirdLife International 2001).

Text account compilers
Benstead, P., Bird, J., Calvert, R., Crosby, M., Lascelles, B., McClellan, R., Symes, A., Taylor, J., Martin, R

Garnett, S., Green, P., Hennicke, J., James, D., Low, T., O'Dowd, D.

Recommended citation
BirdLife International (2014) Species factsheet: Fregata andrewsi. Downloaded from on 24/04/2014. Recommended citation for factsheets for more than one species: BirdLife International (2014) IUCN Red List for birds. Downloaded from on 24/04/2014.

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 - Christmas frigatebird (Fregata andrewsi) 0

Key facts
Current IUCN Red List category Critically Endangered
Family Fregatidae (Frigatebirds)
Species name author Mathews, 1914
Population size 2400-4800 mature individuals
Population trend Decreasing
Distribution size (breeding/resident) -
Country endemic? No
Links to further information
- Additional Information on this species