Data Zone
Justification of Red List category
D. menagei qualifies as Endangered due to its small geographic range (AOO/EOO), number of locations, and a continuing decline in the area, extent, and quality of habitat caused by deforestation and habitat degradation in its its very range.
Population justification
The population is estimated at 600-1,100 individuals, and 400-1,000 mature individuals (breeding adults). This estimate is calculated from surveys for D. menagei targeting five sites on the edges of the Calatrava, San Andres, San Agustin Watersheds Forest Reserve (CSASAWFR) in May 2017 (Sarenas and Meren 2017). This survey found a density of D. menagei of 8 birds/km2 (Sarenas and Meren 2017). The density was extrapolated to a minimum area of suitable habitat of 75 km2 and a maximum of 140 km2 (sRedList [2023] using data from ESA [2022]). This method gave (rounded) population estimates of 600-1,100, most of which (400-1,000) were assumed to be breeding adults given the species' short generation length).
Trend justification
Currently, there has only been a single survey for the species which provides sufficient data to estimate a population size (Sarenas and Meren 2017). Therefore, it is not possible to obtain a reliable quantitative trend for the population over time. However, the species is precautionarily suspected to be declining due to localised deforestation, illegal logging, and expanding agricultural activity (Rocamora and Yeatman-Berthelot 2020). Large areas of suitable habitat have already been converted to pasture and coconut plantations (Allen 2006) and, given the species' likely intolerance to open habitats (Sarenas and Meren 2017), it is likely even moderate continuations of loss and degradation are still causing a decline in mature individuals. Although there has been only a modest 2.4% recent decline in overall forest cover between 2012 and 2022 (Global Forest Watch 2024, based on data from Hansen et al. [2013] and methods disclosed therein), the continued degradation of forest on Tablas is likely to result in a decline of suitable habitat for the species even if overall forest loss is minimal.
Dicrurus menagei is endemic to the island of Tablas in the Philippines (Rocamora and Yeatman-Berthelot 2020). By 1997 it was considered probably extinct (Collar 1997); however, observations since 1998 have confirmed that the species is extant, albeit rare (Allen 2006, Sarenas and Meren 2017, eBird 2024). On Tablas, the species is known from the north, having been observed most frequently within the Calatrava, San Andres, San Agustin Watershed Forest Reserve (CSASAWFR) (Allen 2006). Generally, the species is likely to be found in the Balogo, Dobdoban, Calatrava, and San Agustin regions, occurring in native mature forest close to streams (Allen 2006, Sarenas and Meren 2017, eBird 2024).
The species is possibly extant further south in suitable habitat on the remainder of Tablas, but there have been no surveys to confirm presence/absence.
D. menagei occurs in the mid-canopy of relatively mature, closed-canopy forest (Rocamora and Yeatman-Berthelot 2020). Although the species is occasionally seen in edge habitats, it never occupies open areas and appears to have a strong preference for undisturbed remnant forest, close to streams (Allen 2006, Sarenas and Meren 2017).
The species is insectivorous, and hawks prey in the air as well as foraging among leaves, trunks, and vines (Rocamora and Yeatman-Berthelot 2020).
The species is primarily threatened by the loss and degradation of its habitat across its range. Any degradation of habitat is likely to be detrimental to the species, as it preferentially occupies mature forest, and avoids open areas (Sarenas and Meren 2017).
Since the 19th century, most low-lying areas on Tablas have been converted to pasture and coconut plantations (Allen 2006). Additionally, degradation of the species habitat is widespread from ongoing impacts including illegal logging, illegal occupancy, slash-and-burn activities, and unsustainable harvesting of non-timber products (Hernandez 2020, Sarenas and Meren 2017).
The exact magnitude and impact of these activities on the D. menagei is poorly understood, and further research is required on the population response to these threats. However, there are reportedly few forest patches that exceed 100ha, and a complete lack of mature forest south of the current known range (Allen 2006) where the species is considered potentially extant. Given the small geographic range of the species, even a low rate of habitat degradation is likely to be detrimental to the overall population.
Conservation Actions Underway
A substantial portion of the species range is protected in the Calatrava, San Andres, San Agustin Watersheds Forest Reserve (Protected Planet 2024). The Philippines' Department of Environment and Natural Resources had initiated reforestation activities at one site on on the eastern edge of the reserve (Sarenas and Meren 2017). Additionally, a study based in the reserve has established a baseline of the floral composition and diversity of the island to inform further vegetation monitoring and conservation action (Hernandez 2020).
35·5 cm. Distinctive drongo with very long (164–192 mm) and very deeply forked (70 mm) tail, elongated outer rectrices curving rather widely outwards and slightly upwards; when perched on branch, may remain in horizontal position, with tail hanging vertically down. General colour of plumage is dull black with purple tinge, velvety (rather than glossy); has small neck hackles, short scanty breast spangles; iris dark brown; bill and legs black. Differs from D. hottentottus mainly in tail shape and length. Sexes similar, female a little smaller than male. Juvenile has brownish-black head and underparts, iridescent blue-black back and wings, tail splayed at end. Voice: Poorly known; seems not to be very vocal (unlike both D. hottentottus and D. balicassius), and vocalizations appear to be distinct from those of nearby race palawanensis of D. hottentottus. A typical call, lasting c. 1 second, a rasping sound like that of a cicada (Cicadidae), uttered irregularly at intervals of 2–10 seconds; another typical rasping, "dzak-tsee-ik", in duet occasionally answered with short "jieeh" call. Also "tsee-ik" call, sometimes accompanied by opening and closing of tail in scissor fashion. Appears not to act as flock sentinel.
Text account compilers
Richardson, L.
Contributors
Allen, D., Hutchinson, R., Taylor, J. & Westrip, J.R.S.
Recommended citation
BirdLife International (2024) Species factsheet: Tablas Drongo Dicrurus menagei. Downloaded from
https://datazone.birdlife.org/species/factsheet/tablas-drongo-dicrurus-menagei on 27/11/2024.
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 27/11/2024.