|Location||Bonaire, Sint Eustatius and Saba (to Netherlands), Saba|
|Central coordinates||63o 14.17' West 17o 37.86' North|
|IBA criteria||A2, A4ii, B4ii|
|Altitude||0 - 887m|
|Year of IBA assessment||2007|
Ornithological information The Saban population of Red-billed Tropicbirds has been estimated at 750-1,000 breeding pairs, meeting the requirement for more than 1% of the global estimated population (20,000). They can be found nesting around the entire perimeter of the island in coastal cliffs and xeric, rocky hills. Despite being the national bird of Saba and familiar to residents, the Audubon’s Shearwater population is much more difficult to estimate accurately due to inconspicuous nesting habits and inadequate data. Because all coastal areas are cliffs, there is a tremendous amount of potential habitat. Indeed Lee (2000) has placed the population at 1,000 individuals based on available habitat. One shearwater was found on an egg near Sulpher Mine in February 2002. No calls were heard during 10 hours of nocturnal observations in February (Collier et al. 2002). In April 2004, two hours of nocturnal call-playback resulted in one response by a shearwater near The Bottom. In May 2004, four hours of nocturnal call-playback resulted in three responses near The Bottom and 15-20 responses at Sulpher Mine. It is possible there is no peak in breeding activity, resulting in a protracted nesting period, which would further hinder population estimates. The steep topography limits accurate nest counts as well, although numbers of flying or calling adults may be used. Although these are the only known estimates, there is sufficient evidence to conclude that Saba meets the globally important criteria for Audubon’s Shearwater. Some regionally limited species can be found in pockets of habitat along the coastal zone, these include: Green-throated Carib Eulampis holosericeus, Antillean Crested Hummingbird Orthorhyncus cristatus, Pearly-eyed Thrasher Margarops fuscatus, and Lesser Antillean Bullfinch Loxigilla noctis.
Site description Saba Coastline includes all areas from the waterline to 400 meters inland around the perimeter of this small island. Because Saba’s coast is composed solely of cliffs, Red-billed Tropicbirds can be found all around the island. This habitat also is appropriate for Audubon’s Shearwater, a species which is much more difficult to detect but breeds on the island. The IBA should include Rainforest Ravine, part of the proposed Saba National Land Park, the only site where nesting of Audubon’s Shearwater has been confirmed in recent decades. The only human settlements along the coast are at Fort Bay, where a dock, several buildings, a rock quarry, and landfill exist. It is also a Tropicbird research site.
|Species||Season||Period||Population estimate||Quality of estimate||IBA Criteria||IUCN Category|
|Audubon's Shearwater Puffinus lherminieri||breeding||2000||1,000 individuals||medium||B4ii||Least Concern|
|Red-billed Tropicbird Phaethon aethereus||breeding||2000||750-1,000 breeding pairs||medium||A4ii||Least Concern|
|Bridled Quail-dove Geotrygon mystacea||resident||2006||-||-||A2||Least Concern|
|Purple-throated Carib Eulampis jugularis||resident||2006||present [units unknown]||-||A2||Least Concern|
|Green-throated Carib Eulampis holosericeus||resident||2006||present [units unknown]||-||A2||Least Concern|
|Antillean Crested Hummingbird Orthorhyncus cristatus||resident||2006||present [units unknown]||-||A2||Least Concern|
|Caribbean Elaenia Elaenia martinica||resident||2006||-||-||A2||Least Concern|
|Pearly-eyed Thrasher Margarops fuscatus||resident||2006||present [units unknown]||-||A2||Least Concern|
|Lesser Antillean Bullfinch Loxigilla noctis||resident||2006||present [units unknown]||-||A2||Least Concern|
|IUCN habitat||Habitat detail||Extent (% of site)|
|Forest||Elfin; Second-growth & disturbed||-|
|Land-use||Extent (% of site)|
|Notes: Land use is limited to grazing by free roaming goats and quarry work around Well's Bay.|
Other biodiversity The single endemic vertebrate is Anolis sabanus. The gecko Sphaerodactylus sabanus has a restricted range. Hunting has caused The Mountain Crab Gecarcinus ruricola to now be considered endangered on the island. The bat sub-species Natalus stramineus stramineus is endemic to Saba.
Management considerations Free roaming goats cause erosion and trample nesting burrows. Introduced predators, such as rats and feral cats and dogs, consume nest contents and attack fledged birds.
Protection status The proposed Saba National Protected Area encompasses the coastal area around Sulpher Mine, a key Red-billed Tropicbird nesting site. It also includes the adjacent ghauts, or canyons, which are nesting areas for Audubon’s Shearwater. The Protected Area extends up the north slope of the island to the elffin forest near the peak of Mount Scenery.
Conservation response The non-profit Island Conservation Effort, headed by Martha Walsh Mc-Gehee, has recently concluded a multi-year Red-billed Tropicbird nest productivity and site/mate fidelity study at a colony near the Fort Bay landfill. The non-profit Environmental Protection In the Caribbean has continued checks of the study area when possible and has also conducted searches for Audubon’s Shearwater.
References Augustinus, P.G.E.F., R.P.R. Mees and M. Prins. 1985. Biotic and Abiotic Components Of the Landscapes of Saba (Netherlands Antilles). Uitgave Natuurwetenschappelijke Studiekring voor Suriname en de Nederlandse Antillen 115.Collier, N.C., A.C. Brown, and M. Hester. 2002. Searches for Seabird Breeding Colonies in the Lesser Antilles. El Pitirre 15(3).Hoogerwerf, A. 1977. Notes on the birds of St. Martin, Saba, and St. Eustatius. Studies on the Fauna of Curacao and other caribbean islands 54(176):60-123.Lee, D.S. 2000. Status and Conservation Priorities for Audubon's Shearwaters in the West Indies. Pp 25-30 in Status and Conservation of West Indian Seabirds (E.A. Schreiber and D.S. Lee, eds.).Society of Caribbean Ornithology, Special Publication No. 1, Ruston, LA.Rojer, A. 1997a. Biological Inventory of Saba. Unpublished Report. Carmabi Foundation. Curaçao, Netherlands Antilles.Stuffers, A.L. 1956. The vegetation of the Netherlands Antilles. Studies of the Flora of Curaçao and Other Caribbean Islands 1(15). Van Halewyn, R. and R.L. Norton. 1984. The status and conservation of seabirds in the Caribbean. Pp 169-222 in Status and conservation of the world's seabirds (J.P. Croxall, P.G.H. Evans, and R. Schreiber, Eds.). ICBP Technical Publication No. 2 Cambridge, United Kingdom.Voous, K. H. 1955.The birds of the Netherlands Antilles. Curaçao: Uitg. Natuurwet. Werkgroep Ned. Ant.Voous, K. H.1983. Birds of the Netherlands Antilles. 2nd ed. De Walburg Pers, Zutphen, Netherlands.Walsh-McGehee, M. 2000. Status and Conservation Priorities for White-tailed and Red-billed Tropicbirds in the West Indies. Pp 31-38 in Status and Conservation of West Indian Seabirds (E.A. Schreiber and D.S. Lee, eds.). Society of Caribbean Ornithology, Special Publication No. 1, Ruston, LA.Westermann, J. H., H. Kiel. 1961. The Geology of Saba and St. Eustatius, with Notes on the Geology of St. Kitts, Nevis and Montserrat (Lesser Antilles). Uitgaven Natuur Wetenschappelijke Studiekring Voor Suriname en de Nederlandse Antillen 24, Utrecht, The Netherlands.
Contribute Please click here to help BirdLife conserve the world's birds - your data for this IBA and others are vital for helping protect the environment.
Recommended citation BirdLife International (2013) Important Bird Areas factsheet: Saba. Downloaded from http://www.birdlife.org on 20/06/2013
To provide new information to update this factsheet or to correct any errors, please email BirdLife