Current view: Text account
Site description (2012 baseline):
Site location and context
A rocky island of c500m in length and about 60m wide.
Listed because of its large colony of Lesser Frigatebird (>5,000 individuals present in 2010). There were c50 pairs of Brown Booby in 2010 - a previous report in 1924 had estimated c500 pairs. By contrast 25 pairs of Red-footed Booby were present in 2010, less than 100 pairs were counted in 1924. A dozen pairs of Brown Noddy were also present in 2010.
A sparsely vegetated rocky island. Site of a seabird colony.
Pressure/threats to key biodiversity
Climate change is listed as the third greatest threat to seabirds globally (Croxall et al. 2012). It is predicted to decrease the land area of low-lying Pacific islands and cause complete inundation of some islands (IPCC 1997) leading to substantial population declines (Hatfield et al. 2012). Although no current data or predictions are available specific to this IBA climate change represents a potential threat to this site owing to the risk of future sea level rise leading to inundation, and increased frequency of storms.
Human disturbance and direct harvesting of seabirds are listed as threats to 26 and 23 of the 97 globally threatened seabirds respectively (Croxall et al. 2012). For Near Threatened and Least Concern species it is likely that human disturbance and consumption affect an even greater proportion, particularly of tropical species, for which major reductions in populations and/or breeding sites are increasingly indicated but seldom quantified, especially across the whole range of the many wide-ranging tropical seabird species (Croxall et al. 2012). Human disturbance and direct harvesting may occur at this site. The sustainability of such harvests is unknown but it may represent a threat to this population.
Invasive Alien Species represent the greatest threat to seabirds globally (Croxall et al. 2012), causing adult mortality and reduced productivity owing to egg and chick predation. No data exists on the presence of invasive alien species at Vanua Masi Islet. Polynesian Rat is ubiquitous throughout the Pacific (IUCN SSC Invasive Species Specialist Group 2012) and is assumed to be present. Polynesian Rat has been recorded predating adult seabirds as well as eggs and chicks (Kepler 1967). They have precipitated island extinctions in small-bodied, ground-nesting seabirds, but their impacts on larger or arboreal nesting seabirds appear to be lower (Atkinson 1985, Jones et al. 2008). Black Rat, Brown Rat, Feral Cat, Feral Pig and Small Indian Mongoose are all plausible but unconfirmed residents. Each can potentially cause declines in seabird colonies, and ungulates can exacerbate the threat from other invasive mammals through habitat modification (Atkinson 1985, Rodríguez et al. 2006, Jones et al. 2008, Duffy 2010). Overall, invasive mammals are suspected to be present and are likely to be having a limiting effect on seabirds, or causing population declines.
Conservation responses/actions for key biodiversity
None known
No. The site is listed as a 'Site of National Significance' in Fijis NBSAP.
Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Vanua Masi Islet (Fiji). Downloaded from
https://datazone.birdlife.org/site/factsheet/vanua-masi-islet-iba-fiji on 19/12/2024.
