Manowar and Rocky Islands

Site description (2008 baseline):

Site location and context
Rocky and Manowar Islands are both small islands in the southern Gulf of Carpentaria about 40 km distant from the nearest substantial land on Mornington Island. The two slightly raised islands support large numbers of breeding seabirds, particularly Brown Booby on both islands and Lesser Frigatebird on Manowar Island. The climate is monsoonal with an extended dry season from May to November and a hot wet season from December to April.

Key biodiversity
Large numbers of Australian Pelican and small numbers of Eastern Reef Egret, Osprey and White-bellied Sea-Eagle breed on the islands.

Non-bird biodiversity: The islands are notable for basking by Green Turtle between breeding attempts in the winter (Garnett et al. 1985). An undescribed legless lizard, Lerista aff. orientalis, has been recorded from Rocky Island (Garnett and Crowley 1987a), and must be a relic from the Pleistocene when lower sea level meant the islands were connected to the mainland.

Pressure/threats to key biodiversity
Eradicate Black Rat from Rocky Island. Monitor for other introduced/invasive species and excessive disturbance by fishing tourism, particularly on Manowar Island.

Conservation responses/actions for key biodiversity
Included within the Wellesley Islands Protected Wildlife Area designated under the Gulf of Carpentaria Inshore Fin Fish Management Plan. The islands were surveyed for birds in 1982 and 1992.

Land ownership
Traditional owners are Lardil people: Rocky Island known as Kalamburriya, Manowar Island known as Delmerriya or Wudma. Native title exists over the islands.

Site access / Land-owner requests
Permission to visit islands should be sought from Mornington Island Shire Council.

THe nomination was prepared by Stephen Garnett.

Recommended citation
BirdLife International (2023) Important Bird Area factsheet: Manowar and Rocky Islands. Downloaded from on 23/09/2023.