In addition, proponents and land managers should refer to the Recovery Plan (where available) or the Conservation Advice (where available) for recovery, mitigation and conservation information.
|EPBC Act Listing Status||
Listed migratory - JAMBA, ROKAMBA
|Adopted/Made Recovery Plans|
|Policy Statements and Guidelines||
Marine bioregional plan for the Temperate East Marine Region (Department of Sustainability, Environment, Water, Population and Communities (DSEWPaC), 2012aa) [Admin Guideline].
Offshore and foraging pelagic seabirds - A Vulnerability Assessment for the Great Barrier Reef (Great Barrier Reef Marine Park Authority (GBRMPA), 2011h) [Admin Guideline].
Federal Register of
List of Migratory Species (13/07/2000) (Commonwealth of Australia, 2000b) [Legislative Instrument].
Declaration under section 248 of the Environment Protection and Biodiversity Conservation Act 1999 - List of Marine Species (Commonwealth of Australia, 2000c) [Legislative Instrument].
Environment Protection and Biodiversity Conservation Act 1999 - Listed Migratory Species - Approval of an International Agreement (Commonwealth of Australia, 2007h) [Legislative Instrument].
Documents and Websites
|State Listing Status||
|Scientific name||Sula dactylatra |
This is an indicative distribution map of the present distribution of the species based on best available knowledge. See map caveat for more information.
Scientific name: Sula dactylatra
Common name: Masked Booby
Other names: Blue-faced Booby, White or Whistling Booby, Masked Gannet, Lark
Conventionally accepted as Sula dactylatra (Christidis & Boles 2008). Six subspecies are recognised (Christidis & Boles 2008; Marchant & Higgins 1990):
- Sula dactylatra dactylatra of the Atlantic Ocean and Carribean Sea
- S. d. melanops of the western Indian Ocean
- S. d. personata of central and western Paciifc Ocean, including Queensland
- S. d. granti of the Pacific Ocean
- S. d. bedouti of the eastern Indian Ocean, including islands off Western Australia, Cocos-Keeling Islands and Ashmore Reefs
- S. d. tasmani (which includes those previously identified as S. d. fullagari) of the Tasman Sea, including Norfolk, Lord Howe and Kermadec Islands.
The largest and heaviest of the booby (Sulidae) family, the Masked Booby has a streamlined white body with a narrow (from base of bill to just behind the eyes) black mask on the face, and long narrow wings of mainly white with black tips to the flight feathers. The pointed bill on most individuals is yellow with a black base, however can vary from yellow-green, olive, rosy pink to orange (NSW NPWS 1999cq). The tail is also pointed. The Lord Howe Island population, which belongs to the S. d. tasmani subspecies, has brownish eyes, compared to birds at most other locations which have yellow eyes (NSW DECCW 2005op).
The Masked Booby is 75–85 cm long, with a 160–170 cm wingspan and weighs 1200-2200 g (Marchant & Higgins 1990; NSW NPWS 1999cq). Sexes are alike, but the male has a brighter yellow bill, and there is no seasonal variation in plumage (Lindsay 1986; Marchant & Higgins 1990). Juvenile Masked Boobys are mostly grey-brown above and white below, with a diagnostic white collar and dark hooded appearance (Marchant & Higgins 1990; NSW NPWS 1999cq). The Masked Booby is a more solitary bird when flying or feeding than other species of booby or gannet, but will form loose congregations most notably on return to breeding islands, and breeds colonially and roosts in groups (Marchant & Higgins 1990).
In Australia, the Masked Booby ranges from the Dampier Archipelago in Western Australia (WA), along the entire north coast and east coast to Brisbane. Individuals have also been recorded in Newcastle (NSW), the NSW north coast and Barrow Island (WA) (Marchant & Higgins 1990; NSW NPWS 1999cq). Few records have been made in the Northern Territory (Marchant & Higgins 1990). Individuals regularly occur on islands off Australia, including Lord Howe, Norfolk, Kermadec and the Cocos-Keeling Islands (Marchant & Higgins 1990). The breeding population on Lord Howe Island (Mutton Bird Point, King Point, Roach Island, South Island, Sugarloaf Island, Mutton Bird Island, Gower Island, Sail Rocks and Ball's Pyramid) is the most southerly breeding colony in the world (NSW DECCW 2005op; Priddel et al. 2005).
The Masked Booby is widespread in tropical waters between 30° N and 30° S in the Pacific, Indian and Atlantic Oceans and usually found near deep waters (Marchant & Higgins 1990). Masked Boobys are not migratory; however, individuals may range widely from their breeding islands in search of food (Hutton 1991).
In the Atlantic the Masked Booby is known from the Caribbean to Ascension Islands. The species is recorded in the Indian Ocean, in waters off east Africa and also the Arabian Peninsula but not in waters between: then widely from Indonesia (Sumatra) through northern Australian waters across the Pacific to western, central and southern America. In New Zealand, there are few recorded sightings of the Masked Booby, but include Gannet Island (west of North Cape), the Firth of Thames and Miranda (Marchant & Higgins 1990).
Worldwide, the Masked Booby is estimated to occupy an area of approximately 102 000 km2 (Birdlife International 2010e). The global population is difficult to estimate but possibly several hundred thousand birds (del Hoyo et al. 1992). Sula dactylatra melanops is stated to be declining rapidly but other populations are not threatened (del Hoyo et al. 1992). Globally, the Masked Booby is classified as of Least Concern by the IUCN (2011).
The total Australian Masked Booby population is estimated to be between 3750–4270 breeding pairs (Ross et al. 1996b). The subspecies Sula dactylatra bedouti and S. d. tasmani each breed at fewer than five locations within Australia and have been classified as Vulnerable by Garnett and Crowley (2000). Within Australia and surrounding islands breeding locations and maximum numbers of pairs, (unless stated as nests or birds) where known, include those listed below (Burbidge & Fuller 1996; Marchant & Higgins 1990; QPWS 2002a).
|State/offshore area||Location||Sub-location||Maximum pairs|
|Western Australia||Bedout Island||400|
|Ashmore Reef group||1–2|
|Herald Group||South-west Cay||122|
|Magdelaine Cay||22 nests|
|Coringa Group - Chilcott Island||48 nests|
|Brodie Island||36 nests|
|Great Barrier Reef||Moulter Cay||100|
|Sand Bank No 8||1|
|Sand Bank No 1||1|
|Swain Reefs||Riptide Cay||43|
|Lord Howe Island||100s|
|Norfolk Island||Nepean Island||200|
|Kermadec Island||< 100|
|Keeling Island||about 30|
The Masked Booby is a pelagic marine bird using tropical and subtropical waters, although off Peru where warm water extends into the temperate zone, the species is found further south than usual. Distribution of the species may be determined by the distribution of flying fish (Exocoetidae family), the main food resource. In tropical zones, the species possibly forages at up-wellings of cool nutrient-rich waters, especially when breeding (Marchant & Higgins 1990).
The Masked Booby breeds on tropical oceanic islands, atolls and cays, usually far from mainland areas. Proximity to clear, deep water is important in choice of nesting grounds. Areas of level open ground are preferred for nest sites and colonies extend from central areas to water's edge, just above high-water marks, on bare surfaces of sand, guano, coral fragments or lava, or among low cover of grasses, herbs or shrubs. Where vegetation encroaches, colonies may become restricted to smaller and smaller areas of bare ground (Marchant & Higgins 1990). On Lord Howe Island, the Masked Booby is said to breed on high open areas where they can take off directly into the wind (NSW DECCW 2005op).
The Masked Booby roosts on the ground beside their nests when breeding, although sometimes breeding birds roost on beaches near colonies. Non-breeding adults and juveniles roost on the ground near colonies in small groups. Outside of the breeding season, birds roost on other islands or on the sea surface. After foraging, birds may rest on beaches or sand banks, often in mixed species flocks (Marchant & Higgins 1990).
The Masked Booby breed from around three years of age (O'Neill et al. 1996), and birds are likely to live for over 20 years (USFWS 2010). The annual mortality rate of adults has been recorded as approximately 6% (del Hoyo et al. 1992).
The Masked Booby is monogamous, nesting annually, usually in the same area, and often associated with nests of the Brown Booby (Sula leucogaster). The density of nests varies at sites and the species defends the area surrounding the immediate nest. The nest is usually a cleared, circular area (Marchant & Higgins 1990). Both parents incubate one or two large eggs for a period of 40 to 49 days.
Siblicide (in which one chick kills the other either directly, by competition for food, or by forcibly ejecting from the nest) normally ensures only one chick per clutch survives (Hutton 1991; Marchant & Higgins 1990). Both adults feed the remaining chick for approximately 17 weeks till fledging, and then 4–8 weeks post fledging (Marchant & Higgins 1990). Breeding success is variable depending on conditions mainly for food resources, for example at Kure during a study of six breeding seasons, total success varied from 51.1 to 90.3% (Marchant & Higgins 1990).
Throughout the range of the species, breeding is recorded in every month. In Australia, the Masked Booby has a laying period of January to July on Cocos-Keeling Islands, with young present from April-December (Marchant & Higgins 1990). At Pandora Cay in the Coral Sea, laying occurs through the whole of the year with a peak in September to early November, and young are present all year, though the majority in summer (King cited in Marchant & Higgins 1990). On Raine Island, laying starts during or after August, with young present November to May, and at Swain Reefs the Masked Booby breeds throughout the year but peak laying occurs in winter months (Heatwole et al. 1996). On Lord Howe Island, peak laying is in December (Marchant & Higgins 1990).
The diet of the Masked Booby is primarily comprised of fish with some cephalopods (squids, Teuthida order). Food is obtained by deep plunging in the ocean from a height of 12–100 m, mostly 15–35 m to depths probably exceeding 3 m, although sometimes in water as shallow as 1.5 m (Marchant & Higgins 1990). Most prey is swallowed head first, under water after being speared with the bird's sharp beak (Hutton 1991). The species rarely takes flying fish by flight-feeding and have been observed using aerial piracy, but most food is taken under water. The Masked Booby usually fish in pairs or small groups, and sometimes in association with other species. The extent of feeding home-ranges is unknown. On return to breeding colonies after foraging, Masked Boobys are often harassed by frigatebirds (fregatidae family) to regurgitate food, so birds will often form groups before entering the colony (Marchant & Higgins 1990). During the breeding season the Masked Booby is recorded foraging far offshore. Off Hawaii, birds have been seen more than 80 km from shore and in the Indian Ocean most adults are recorded foraging 160 to 320 km from breeding islands (Marchant & Higgins 1990).
The Masked Booby is dispersive, moving either long or short distances from breeding islands in search of food. Most immatures appear to return to their natal island to breed and, once a breeding site has been established, individuals are usually faithful to this locality. Immatures and non-breeders disperse widely mostly to the north with little overlap between populations on different islands: most birds from Kermadec Island are recovered in Vanuatu and New Caledonia, and those from Lord Howe Island on east coast Australia. Those from Raine Island are recorded in south-east Papua New Guinea and surrounding areas (Marchant & Higgins 1990)
The Masked Booby is said to superficially resemble the Australasian Gannet (Morus serrator), but the former has a whiter head and the tail is black (Lindsay 1986). Sula dactylatra tasmani is separated from S. d. personata by a darker coloured iris (Marchant & Higgins 1990).
Guano digging at Raine Island in the 1800s negatively affected the breeding colony, but that population is now recovering. Mining may have improved breeding habitat for the long-term by providing flat bare exposed ground (Marchant & Higgins 1990).
Human predation still impacts the Masked Booby. Eggs and chicks are taken and general disturbance of nesting colonies increases breeding failures. Other predators include rats (Rattus spp.), the Silver Gull (Larus novaehollandiae) and the Buff-banded Rail (Gallirallus philippensis) which take eggs and small chicks. At Raine Island and Pandora Cay, the Green Turtle (Chelonia mydas) destroy some nests (Marchant & Higgins 1990; Garnett & Crowley 2000).
Human visitation or disturbance of breeding sites may also impact on the species via an increase in the numbers of gulls (Laridae family), usually due to foodscraps, and hence increased predation pressure (Walker 1988). Increases in numbers of tourists visiting the Great Barrier Reef and advances in vessel technology are also likely to lead to an increasing demand for visitation to seabird islands in this region (Stokes et al. 1996; WBM Oceanics & Claridge 1997).
Climate change and associated changes in weather, ocean currents and sea levels may have a dramatic impact on this species, since it nests on low islands and nests can be inundated by high tides or flooded (Coate 1997; Marchant & Higgins 1990). The El Niño Southern Oscillation has been suggested as the reason for previous breeding failures on Christmas Island, where increased sea surface-temperature, deepened thermocline and high sea-level preceded a failure of food supplies and heavy rainfall may have flooded nests and inhibited breeding activity (Marchant & Higgins 1990).
Management efforts such as the eradication of rats (Rattus spp.) may help breeding populations recover. At Bedout Island rats were eradicated in 1981 and the breeding population subsequently increased from 120 pairs to more than 170 pairs (Burbidge & Fuller 1996; Fuller & Burbidge 1998), however, they still breed on Norfolk and Lord Howe Islands, despite the presence of rats and the Cat (Felis catus) (Garnett & Crowley 2000). An apparently successful rat eradication program from 1985–91 on South-west Coringa Islet, Coral Sea, may also have benefited the species (Environment Australia 2001g).
Regulation of human activities at breeding colonies to ensure birds are not disturbed and breeding success is not affected would be beneficial (WBM Oceanics & Claridge 1997).
For Sula dactylatra tasmani, Garnett and Crowley (2000) suggest the creation and implementation of protocols to reduce the impact of tourism on Phillip Island. Garnett and Crowley (2000) suggest, as well as ongoing monitoring, the following management for S. d. bedouti:
- manage feeding habitat if necessary
- use education and other means to ensure strict quarantine on North Keeling Island
- limit human access to other breeding islands.
Marine bioregional plans have been developed for four of Australia's marine regions - South-west, North-west, North and Temperate East. Marine Bioregional Plans will help improve the way decisions are made under the EPBC Act, particularly in relation to the protection of marine biodiversity and the sustainable use of our oceans and their resources by our marine-based industries. Marine Bioregional Plans improve our understanding of Australia's oceans by presenting a consolidated picture of the biophysical characteristics and diversity of marine life. They describe the marine environment and conservation values of each marine region, set out broad biodiversity objectives, identify regional priorities and outline strategies and actions to address these priorities. Click here for more information about marine bioregional plans.
The Masked Booby has been identified as a conservation value in the Temperate East (DSEWPaC 2012aa) Marine Region. See Schedule 2 of the Temperate East Marine Bioregional Plan (DSEWPaC 2012aa) for regional advice. Maps of Biologically Important Areas have been developed for Masked Booby in the Temperate East (DSEWPaC 2012aa) Marine Region and may provide additional relevant information. Go to the conservation values atlas to view the locations of these Biologically Important Areas. The "species group report card - seabirds" for the Temperate East (DSEWPaC 2012aa) Marine Region provides additional information.
Management documents relevant to the Masked Booby are at the start of the profile. The Action Plan for Australian Birds (Garnett & Crowley 2000) also contain actions aimed at the conservation of migratory birds within Australia.
The following table lists known and perceived threats to this species. Threats are based on the International Union for Conservation of Nature and Natural Resources (IUCN) threat classification version 1.1.
|Threat Class||Threatening Species||References|
|Biological Resource Use:Biological Resource Use:Unspecified use||Sula dactylatra in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage, 2006yh) [Internet].|
|Biological Resource Use:Fishing and Harvesting Aquatic Resources:Mortality due to capture, entanglement/drowning in nets and fishing lines||
Sula dactylatra in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage, 2006yh) [Internet].
Lord Howe Island Biodiversity Management Plan (NSW Department of Environment and Climate Change (NSW DECC), 2007b) [Recovery Plan].
|Biological Resource Use:Hunting and Collecting Terrestrial Animals:Direct exploitation by humans including hunting||Sula dactylatra in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage, 2006yh) [Internet].|
|Climate Change and Severe Weather:Habitat Shifting and Alteration:Global warming and associated sea level changes||Sula dactylatra in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage, 2006yh) [Internet].|
|Climate Change and Severe Weather:Habitat Shifting and Alteration:Habitat modification, destruction and alteration due to changes in land use patterns||Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks (DNP), 2010a) [State Recovery Plan].|
|Climate Change and Severe Weather:Temperature Extremes:climate change|
|Human Intrusions and Disturbance:Human Intrusions and Disturbance:Human induced disturbance due to unspecified activities||
Sula dactylatra in Species Profile and Threats (SPRAT) database (Department of the Environment and Heritage, 2006yh) [Internet].
Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks (DNP), 2010a) [State Recovery Plan].
|Human Intrusions and Disturbance:Recreational Activities:Environemental pressures due to ecotourism|
|Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or predation||Felis catus (Cat, House Cat, Domestic Cat)||Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks (DNP), 2010a) [State Recovery Plan].|
|Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or predation||Rattus rattus (Black Rat, Ship Rat)||Norfolk Island Region Threatened Species Recovery Plan (Director of National Parks (DNP), 2010a) [State Recovery Plan].|
|Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or predation||Canis lupus familiaris (Domestic Dog)|
|Invasive and Other Problematic Species and Genes:Invasive Non-Native/Alien Species:Competition and/or predation by rats|
|Invasive and Other Problematic Species and Genes:Invasive and Other Problematic Species and Genes:Predation, competition, habitat degradation and/or spread of pathogens by introduced species|
|Invasive and Other Problematic Species and Genes:Problematic Native Species:Competition and/or predation by birds|
|Invasive and Other Problematic Species and Genes:Problematic Native Species:Predation by reptiles|
BirdLife International (2010e). Species factsheet: Sula dactylatra. [Online]. Available from: http://www.birdlife.org.
Burbidge, A.A. & P.J. Fuller (1996). The Western Australian Department of Conservation and Land Management seabird breeding islands database. In: Ross, G.J.B., K. Weaver & J.C. Greig, eds. The status of Australia's seabirds Proceedings of the National Seabird Workshop, Canberra, 1-2 November 1993. Page(s) 73-137. Canberra: Biodiversity Group, Env. Aust.
Christidis, L. & W.E. Boles (2008). Systematics and Taxonomy of Australian Birds. Collingwood, Victoria: CSIRO Publishing.
Coate, K. (1997). Seabird islands No. 236: Adele Island, Western Australia. Corella. 21:124-128.
del Hoyo, J., A. Elliot & J. Sargatal (1992). Ostrich to Ducks. In: Handbook of the Birds of the World. 1. Spain: Lynx Edicions.
Environment Australia (2001g). Coringa-Herald National Nature Reserve & Lihou Reef National Nature Reserve Management Plan. Environment Australia, Canberra.
Fuller, P.J. & A.A. Burbidge (1998). Seabird islands No. 239: Bedout Island, Pilbara Region, Western Australia. Corella. 22:113-115.
Garnett, S., J. Szabo & G. Dutson (2011). The Action Plan for Australian Birds 2010. CSIRO Publishing.
Garnett, S.T. & G.M. Crowley (2000). The Action Plan for Australian Birds 2000. [Online]. Canberra, ACT: Environment Australia and Birds Australia. Available from: http://www.environment.gov.au/biodiversity/threatened/publications/action/birds2000/index.html.
Heatwole, H., J.P. O'Neill, M. Jones & M. Preker (1996). Long-term population trends for seabirds in the Swain Reefs, Queensland. In: CRC Reef Research Technical Report. 12. [Online]. Available from: http://www.reef.crc.org.au/publications/techreport/TechRep12.shtml.
Hutton, I. (1991). Birds of Lord Howe Island: Past and Present. Coffs Harbour, NSW: author published.
IUCN (2011). IUCN Red List of Threatened Species. Version 2011.2. [Online]. Available from: http://www.iucnredlist.org/.
Lindsay, T. (1986). The Seabirds of Australia. Angus and Robertson, Sydney.
Marchant, S. & P.J. Higgins (1990). Handbook of Australian, New Zealand and Antarctic Birds. Volume One - Ratites to Ducks. Melbourne, Victoria: Oxford University Press.
NSW Department of Environment, Climate Change and Water (NSW DECCW) (2005op). Masked Booby - profile. [Online]. Available from: http://www.threatenedspecies.environment.nsw.gov.au/tsprofile/profile.aspx?id=10898.
NSW National Parks and Wildlife Service (NSW NPWS) (1999cq). Masked Booby Threatened Species Information. [Online]. Available from: http://www.environment.nsw.gov.au/resources/nature/tsprofileMaskedBooby.pdf.
O'Neill, P., H. Heatwole, M. Preker & M. Jones (1996). Populations, movements and site fidelity of Masked and Brown Boobies on the Swain Reefs, Great Barrier Reef, as shown by banding recoveries. CRC Reef Research Technical Report. 11.
Priddel, D., I. Hutton, S. Olson & R. Wheeler (2005). Breeding biology of Masked Boobies (Sula dactylatra tasmani) on Lord Howe Island, Australia. Emu. 105(2):105-113.
Queensland Parks and Wildlife Service (QPWS) (2002a). Coastal Bird Atlas, Queensland Parks and Wildlife Service, Rockhampton, Qld (curators: P. O'Neill and R. White). Queried 16 April 2002.
Ross, G.J.B., K. Weaver & J.C. Grieg (1996b). The Status of Australia's Seabirds: Proceedings of the National Seabird Workshop, Canberra, 1-2 November 1993. Canberra: Biodiversity Group, Environment Australia.
Stokes, T., K. Hulsman, P. Ogilvie & P. O'Neill (1996). Management of human visitation to seabird islands of the Great Barrier Reef Marine Park region. Corella. 20:1-13.
United States Fish & Wildlife Service (USFWS) (2010). Midway Atoll National Wildlife Refuge, Birds of Midway Atoll- Masked Booby. [Online]. Available from: http://www.fws.gov/midway/mabo.html.
Walker, T.A. (1988). Population of the Silver Gull Larus novaehollandiae on the Capricorn and Bunker Islands, Great Barrier Reef. Corella. 12:113-118. [Online]. Available from: http://www.gbrmpa.gov.au/corp_site/info_services/publications/seabirds/index.html.
WBM Oceanics & G. Claridge (1997). Guidelines for managing visitation to seabird breeding islands. [Online]. Townsville, Queensland: Great Barrier Reef Marine Park Authority. Available from: http://www.gbrmpa.gov.au/corp_site/info_services/publications/seabirds/index.html.
This database is designed to provide statutory, biological and ecological information on species and ecological communities, migratory species, marine species, and species and species products subject to international trade and commercial use protected under the Environment Protection and Biodiversity Conservation Act 1999 (the EPBC Act). It has been compiled from a range of sources including listing advice, recovery plans, published literature and individual experts. While reasonable efforts have been made to ensure the accuracy of the information, no guarantee is given, nor responsibility taken, by the Commonwealth for its accuracy, currency or completeness. The Commonwealth does not accept any responsibility for any loss or damage that may be occasioned directly or indirectly through the use of, or reliance on, the information contained in this database. The information contained in this database does not necessarily represent the views of the Commonwealth. This database is not intended to be a complete source of information on the matters it deals with. Individuals and organisations should consider all the available information, including that available from other sources, in deciding whether there is a need to make a referral or apply for a permit or exemption under the EPBC Act.
Citation: Department of the Environment (2014). Sula dactylatra in Species Profile and Threats Database, Department of the Environment, Canberra. Available from: http://www.environment.gov.au/sprat. Accessed Sat, 8 Mar 2014 22:32:52 +1100.