Family Frogmouths (Podargidae)

Least Concern

Horsfield's Frogmouth (Batrachostomus javensis)


Taxonomy

French: Podarge de Java German: Javafroschmaul Spanish: Podargo de Java
Taxonomy:

Podargus Javensis

Horsfield

, 1821,

Java

.

Much confusion over species limits with regard to this and its close allies. Formerly considered conspecific with B. cornutus by some, but combined study of vocalizations and museum specimens#R supported earlier suggestions that it should be regarded as a distinct species. Sometimes treated as conspecific with B. hodgsoni, but differences in bill size and structure, development of facial bristles, relative tail length and vocalizations, and perhaps also bare-part colours (bill said to be often more straw-coloured), too great. Race affinis sometimes considered a distinct species, and recently treated as such on account of its supposedly distinctive voice#R, but analysis and publication of fuller evidence needed. Race continentalis is apparently connected to affinis by an intermediate population around Khao I Phrom, in C peninsular Thailand; this also recently treated as a full species#R, but again analysis and fuller evidence needed. Likewise, race chaseni, previously considered inseparable from affinis, now thought by some to represent a separate species on basis of some morphological and vocal characters#R. Recent claim of a new species (B. pygmaeus) from Calamian Group (Busuanga I), N of Palawan, in W Philippine Is, seems unconvincing, single specimen on which description based being little different from local chaseni. Since 2005, several observations (and photographs) of a frogmouth on island of Siberut, off W Sumatra, perhaps involve this species or B. cornutus, or alternatively an undescribed taxon#R#R; further study required. Four subspecies currently recognized.

Subspecies and Distribution
  • B. j. continentalis Stresemann, 1937 – Indochinese Frogmouth – SE Myanmar (S Tenasserim) and N, W & S Thailand (S to Nakhon Si Thammarat); also S Laos and C Vietnam (Annam).
  • B. j. affinis Blyth, 1847 – Blyth's Frogmouth – SE peninsular Thailand S to Sumatra and Riau Archipelago, and Borneo.
  • B. j. chaseni Stresemann, 1937 – W Philippines (Culion I, in Calamian Group; Palawan) and Banggi I (off N Borneo).
  • B. j. javensis (Horsfield, 1821) – Javan Frogmouth – Java.
  • Possibly present also on Siberut, off W Sumatra#R#R.

    Descriptive notes

    19–25 cm; mean 46–47 g. Difficult to separate from other small frogmouths except on voice, although in parts of Thailand and on Java and Palawan (Philippines)... read more

    Voice

    Vocalizations stated to differ geographically with, for instance, territorial call of “... read more

    Habitat

    Mainly lowland evergreen forest, preferring dense rainforest, in which it lives mostly in the... read more

    Food and feeding

    Diet consists mainly of insects, particularly beetles and grasshoppers; other records from gut contents include moths, butterflies,... read more

    Breeding

    Few data, even on season: three nests with eggs in Malaysia in Feb, Mar and May, nest also in Malaysia with nestlings in late Jul, and... read more

    Movements

    Apparently sedentary.

    Status and conservation

    Not globally threatened. Previously considered Near Threatened; this assessment probably resulted from taxonomic confusion, since only the Javan nominate subspecies is scarce... read more

    Recommended citation

    Holyoak, D.T. & Kirwan, G.M. (2018). Horsfield's Frogmouth (Batrachostomus javensis). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/55151 on 23 July 2018).