|Central coordinates||145o 58.76' East 16o 36.31' South|
|Altitude||0 - 4m|
|Year of IBA assessment||2009|
Summary Michaelmas Cay is a well-studied island off Cairns which has supported more than 1% of the world population of Crested Tern and Lesser Crested Tern.
Site description Michaelmas Cay is about 40 km east of Cairns in the northern Great Barrier Reef. It is a vegetated sand cay, and covered about 360 m x 50 m in 1984, but is subject to erosion and accretion. The cay is comprised of coral sand with low mats of grasses and herbs, which vary in extent between seasons. It is zoned as a Marine National Park, allowing boat limited visits and diving.
Key Biodiversity Small numbers of breeding Roseate Tern, Black-naped Tern, Sooty Tern (regular counts of 5,000-10,000 pairs), Crested Tern, Common Noddy (max 6000+ pairs in 1982).
|Species||Season||Period||Population estimate||Quality of estimate||IBA Criteria||IUCN Category|
|Lesser Crested Tern Thalasseus bengalensis||resident||1982-1992||1,000-1,623 nests||-||A4i||Least Concern|
|Greater Crested Tern Thalasseus bergii||resident||1982-1992||2,000-6,080 nests||-||A4i||Least Concern|
|2008||high||not assessed||not assessed|
|Medium - based upon reliable but incomplete / partially representative data|
|Climate change and severe weather||storms and floods||likely in long term (beyond 4 years)||whole area/population (>90%)||moderate to rapid deterioration||high|
|Human intrusions and disturbance||recreational activities||happening now||whole area/population (>90%)||no or imperceptible deterioration||low|
|Protected area||Designation||Area (ha)||Relationship with IBA||Overlap with IBA (ha)|
|Great Barrier Reef||World Heritage Site||34,870,000||protected area contains site||2|
|Michaelmas and Upolu Cays||National Park||3||protected area overlaps with site||2|
|IUCN habitat||Habitat detail||Extent (% of site)|
|Coastline||Sand cays, islets & bars||100%|
Land ownership Australian Federal Government with management the responsibility of GBRMPA.
|Land-use||Extent (% of site)|
|nature conservation and research||100%|
Protection status The IBA overlaps with Michaelmas and Upolu Cays National Park.
Acknowledgements Paul O'Neill provided advice and access to the GBR seabird database and the nomination was prepared in consultation with Mike Short.
References GBRMPA. (1997) Guidelines for Managing Visitation to Seabird Breeding Islands. Great Barrier Reef Marine Park Authority unpublished report.
King, B.R. (1985) Michaelmas Cay, Great Barrier Reef, Queensland. Corella 9: 94-96. Queensland Parks & Wildlife Service (2007) GBR seabird database (accessed May 2007).
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Recommended citation BirdLife International (2016) Important Bird and Biodiversity Area factsheet: Michaelmas Cay. Downloaded from http://www.birdlife.org on 31/05/2016
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