Data Zone
Justification of Red List category
This species has a very small range, in which there is a slow continuing decline in habitat quality due to logging and forest clearance. Its population size is thought to be small and there is only one subpopulation, but the current population trend is uncertain, as forest loss has been very slow within its range over the past decade. There is a plan for a major logging operation across a large part of the species's range, but the likely impact on the species's population size is uncertain. For these reasons, the species is listed as Near Threatened.
Population justification
The species is seldom seen and is apparently uncommon (Pratt and Beehler 2015, Beehler and Pratt 2016). Six to ten individuals were seen in a 6.13 km walk through forest at 120-300 m (W. Goulding in litt. 2016). Assuming that this species could be detected up to about 20-25 m either side, this might equate to very approximately 20-46 individuals per km2 (W. Goulding in litt. 2020). The area of the the island is approximately 813 km2, but although there have been records from sea level (Mitchell 2017), the species has been mostly recorded in forest above an elevation of 120 m (W. Goulding in litt. 2020), which may give an area of habitat of 279 km2 (W. Goulding in litt. 2016). Based on an area of 279 - 813 km2 and the population densities above, the population size is estimated to be between 5,580 - 37,398 individuals, which roughly equates to 3,720 - 24,932 mature individuals, here rounded to 3,700 - 25,000. Since there have been few records below 120 m and the area of habitat is estimated to cover only around a third of the area of the island (W. Goulding in litt. 2016), the true value is likely to fall towards the lower end of this range, and is suspected to be around 5,000 (W. Goulding in litt. 2020).
The species has a small range on a single island and there is no indication that there is more than one subpopulation.
Trend justification
There is no population data from which to directly estimate trends. From 2009-2019, approximately 2% of forest with at least 50% canopy cover was lost across Tagula, but the rate of forest loss was lower at higher elevations (Global Forest Watch 2020), so the impact of forest loss on the species's population is expected to have been lower than this. The population size is tentatively suspected to be declining slowly. Over the past ten years, the population size is suspected to have undergone a small reduction of 1-5%.
In 2019, there were plans for commercial logging between Reuwo on the south coast and Rambuso Creek on the north coast (W. Goulding in litt. 2020). Should it go ahead, this could impact up to approximately a third of the species's habitat, but it is unlikely that the species would be completely eliminated from the area of logging. The impacts would be likely to begin within several years, with the full impact occurring ten or more years later (G. Dutson in litt. 2020). Over the next ten years, the population is suspected to undergo a reduction of 1-29%.
Zosterops meeki is confined to Tagula (= Sudest) Island (c.800 km2) in the Louisiade Archipelago of Papua New Guinea. It is a single-island endemic not found on adjoining islands and appears largely restricted to undisturbed forest above 120 m in the centre of the island. The area of habitat within the species's range is approximately 279 km2 (W. Goulding in litt. 2020).
The species has been recorded from sea level (Mitchell 2017) to Mt Riu, the highest point of Tagula, at 801 m, but it has been mostly recorded at middle elevations over 120 m (W. Goulding in litt. 2016). Primarily recorded in the forested interior, but has been seen in mangrove and in secondary regrowth behind the littoral zone (Mitchell 2017). It is not readily observed in disturbed habitats (W. Goulding in litt. 2020). A canopy-dwelling species, reluctant to descend to lower forest strata, observed to glean insects off leaves and expected to eat fruits. Individuals were observed traversing ~ 25 m canopy gaps in heavily cyclone impacted forest above 120 m and flying over ~ 100 m of grassland near forest edge. It has been observed in small groups of 2-5 individuals (Mitchell 2017, W. Goulding in litt. 2020).
Logging has degraded some of the lowland forest on Tagula (Beehler 1993). In 2019, there were plans to commercially log forest between Reuwo on the south coast and Rambuso Creek on the north coast. This includes primary habitat for this species, in which it has been observed. Associated roads have also been discussed, that would dissect the island between these two points (W. Goulding in litt. 2020). Shifting agriculture causes small areas of forest loss at lower altitudes, although these areas are then left to regrow. Local human population growth may lead to future impacts through more forest clearance for agriculture (Goulding et al. 2019). Gold prospecting is occurring and mining is a potential threat. Cyclones can cause landslides and damage the forests (Mitchell 2017), and are expected to increase in intensity owing to climate change.
Conservation Actions Underway
A project is underway since 2016 to survey habitat-use and conduct population estimates.
Text account compilers
Wheatley, H.
Contributors
Burrows, I., Derhé, M., Dutson, G., Goulding, W., Mitchell, D. & Symes, A.
Recommended citation
BirdLife International (2024) Species factsheet: Tagula White-eye Zosterops meeki. Downloaded from
https://datazone.birdlife.org/species/factsheet/tagula-white-eye-zosterops-meeki on 24/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 24/12/2024.