Solomon Islands Frogmouth Rigidipenna inexpectata was formally recognised by BirdLife International in 2010, following Cleere et al. (2007), and immediately listed as Least Concern on the basis that it was not considered to approach the thresholds for Vulnerable under any of the criteria.
The population is suspected to be decreasing due to ongoing habitat destruction; however, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (at least a 30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (fewer than 10,000 mature individuals with a continuing decline estimated to be at least 10% over ten years or three generations, or with a specified population structure).
Mapping of the species’s range, however, to follow Cleere et al. (2007) has confirmed that the Extent of Occurrence (EOO) is less than 20,000 km2, currently estimated at 16,700 km2. This meets the EOO threshold for Vulnerable under the B1 criterion on the basis that there is also a continuing decline observed, inferred or projected in any of the following: the EOO, Area of Occupancy, area, extent and/or quality of habitat, number of locations or sub-populations, and number of mature individuals.
Further information is needed before a decision can be made on whether to list the species as Vulnerable or Near Threatened. The species will only qualify as Vulnerable if it is shown that its population is also severely fragmented, or occurs at 10 locations or less, or that there are extreme fluctuations in its range or population size. The species habitat will be regarded as severely fragmented if over 50% is in patches that are too small to support viable populations. If the species does not meet all of the B1 criterion for Vulnerable, it will likely be listed as Near Threatened.
To help in its assessment, further information is requested, particularly on the level of fragmentation in this species’s habitat and hence its population. Information is also invited on the likely population size and rate of decline over 23 years (estimate of three generations), as well as the severity of threats faced by the species.
Cleere, N., Kratter, A. W., Steadman, D. W., Braun, M. J., Huddleston, C. J., Filardi, C. E. and Dutson, G. (2007) A new genus of frogmouth (Podargidae) from the Solomon Islands – results from a taxonomic review of Podargus ocellatus inexpectatus Hartert 1901. Ibis 149: 271-286.
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