Data Zone
Justification of Red List category
This species has a small range and perhaps a relatively small population, and its habitat is being slowly lost and degraded. It is therefore listed as Near Threatened.
Population justification
The population size of this species is unknown. It was formerly estimated to number 2,500-10,000 mature individuals, however this was largely speculation and not born from species-specific data. The island is 144 km2 in size with approximately 123 km2 of forest left in 2020 (Global Forest Watch [2021], using data from Hansen et al. [2013] and methods disclosed therein). Although densities of this species are lacking, it has been described as abundant and among the commonest nine bird species on the island (Diamond et al. 2009). Symposiachrus loricatus occurs at densities of 127-213 birds/km2 (Marsden et al. 1997, Poulsen 1998) on Buru while other small-island monarchs (not Symposiarchus) occur at densities of 16-540 birds/km2 (Engbring et al. 1986, Poulsen 1998). Given these tremendous uncertainties (which at 100% occupancy of Kofiau would be equivalent to 2,000-66,000 birds ([or 1,320-43,500 mature individuals]) the population is best treated as unknown until additional data become available. However, the qualitative descriptions of its abundance suggest that the population probably exceeds 10,000 mature individuals.
Trend justification
Beehler and Pratt (2016) considered the population trend of this species as unknown. Although the species persists in traditional gardens, it is apparently most common in closed-canopy primary and secondary forest. Tree cover loss in the species' range has been minimal (equivalent to c.2% over the past three generations [Global Forest Watch 2021, using Hansen et al. [2013] data and methods disclosed therein]); however, there are additional reports of selective logging (see Diamond et al. 2009, Beehler and Pratt 2016) indicating degradation that is precautionarily thought to be causing a slow decline in mature individuals. The rate of this decline however remains unquantified.
This species is endemic to the 144-km2 island of Kofiau in the West Papuan islands off north-west Papua (formerly Irian Jaya), Indonesia, where it is common and widespread in lowland forest, including secondary forest (Beehler et al. 1986, Diamond et al. 2009).
This species is most common in primary and closed-canopy secondary forest, where is has been described as abundant. Adults also persist in traditional shaded subsistence gardens, although the ability of these gardens to support the species is unknown. It can generally be found at heights of 1-30 m, foraging within trees, rather than at the tips of branches, by hover-gleaning, making quick short hops along a branch, and working vertically up a tree or vine (Diamond et al. 2009).
Much of Kofiau has been selectively logged, and currently the island has no protected area (K. D. Bishop in litt. 1994, 2000). The remaining forest is in slow decline owing to slash-and-burn agriculture, both for subsistence gardens and coconut groves, and small-scale timber extraction (Diamond et al. 2009). Having a distribution on relatively low-lying islands, this species is potentially susceptible to climate change through sea-level rise and shifts in suitable climatic conditions, although the extent to which this would affect S. julianae is wholly unknown.
Conservation Actions Underway
No targeted conservation actions are known for this species and it does not occur in a protected area.
Text account compilers
Berryman, A.
Contributors
Beehler, B.M., Bishop, K.D., Calvert, R. & Taylor, J.
Recommended citation
BirdLife International (2024) Species factsheet: Kofiau Monarch Symposiachrus julianae. Downloaded from
https://datazone.birdlife.org/species/factsheet/kofiau-monarch-symposiachrus-julianae on 18/12/2024.
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 18/12/2024.