Species

Justification
This species qualifies as Vulnerable because it is estimated to have a small population which is suspected to be declining as a result of forest loss.

Taxonomic source(s)
Sibley, C. G.; Monroe, B. L. 1990. Distribution and taxonomy of birds of the world. Yale University Press, New Haven, USA.

Identification
30 cm. Medium-sized forest-dwelling hawk. Adult males have pale grey upperparts; dark primaries; dark sub-terminal band to the tail and pale underparts with rusty breast and flank barring. Females and immatures are rich rufous brown with 3-5 dark bands on the uppertail.

Distribution and population
Accipiter butleri is endemic to the Nicobar Islands in the Bay of Bengal, India, where it is only known with certainty from Great Nicobar, Little Nicobar, Pilo Milo, Kamorta, Teressa, Bompoka, Tillanchong, Katchall and Nancowry islands (Sankaran 1995, BirdLife International 2001, A. P. Zaibin in litt. 2012). As many islands in the archipelago are poorly studied, it is possible that it is more widely distributed. It is evidently very scarce: during three years of surveys, R. Sankaran sighted 20-25 individuals of this species in its entire known range, and no sightings of this species were obtained in the coastal habitats of the Nicobar Islands during fieldwork in 2006 (K. Sivakumar in litt. 2012), whilst fieldwork from March 2009 to August 2011 produced only two sightings of single birds on Nancowry Island (A. P. Zaibin in litt. 2012). The impact of the 2004 tsunami on this species has not been studied (K. Sivakumar in litt. 2012).

Population justification
Its status and population size are very poorly known, owing to its apparent scarcity, the species's restricted range and identification difficulties. Its total population may include c.2,500-5,000 mature individuals (K. Sivakumar in litt. 2012). This equates to c.3,700-7,500 individuals, assuming that mature individuals account for around 2/3 of the total population.

Trend justification
A moderate and on-going population decline is suspected on the basis of rates of habitat loss, but this requires further documentation.

Ecology
This species is apparently restricted to forested habitats. There is very little information available about its breeding and feeding ecology. Lizards and insects have been recorded as food items.

Threats
The primary threat to this species appears to be habitat loss and degradation, and this has accelerated since the arrival of migrants from mainland India in the late 1960s. Clearance for agriculture and development have increased and have exacerbated soil erosion problems. The impacts of the tsunami in 2004, which destroyed significant areas of habitat across the islands, have not been investigated for this species, and it may have had secondary consequences such as increased agricultural encroachment (K. Sivakumar in litt. 2012).

Conservation actions underway
The species is protected under Indian Wildlife legislation. No targeted conservation measures are known to have been implemented.

Conservation actions proposed
Investigate its ecological requirements. Conduct detailed surveys of the archipelago to determine the true status of this species. Develop a community-governed protected area on Katchall (K. Sivakumar in litt. 2012).

References
Sankaran, R. 1995. Avifauna of the Andaman and Nicobar Islands. In: Vijayan, L. (ed.), Avian conservation in India, pp. 56-57. SACON, Coimbatore.

BirdLife International. 2001. Threatened birds of Asia: the BirdLife International Red Data Book. BirdLife International, Cambridge, U.K.

Further web sources of information
Detailed species accounts from the Threatened birds of Asia: the BirdLife International Red Data Book (BirdLife International 2001).

View photos and videos, and hear sounds of this species from the Internet Bird Collection

Text account compilers
Benstead, P., Bird, J., Crosby, M., Taylor, J.

Contributors
Sivakumar, K., Zaibin, A.

IUCN Red List evaluators
Butchart, S., Symes, A.

Recommended citation
BirdLife International (2013) Species factsheet: Accipiter butleri. Downloaded from http://www.birdlife.org on 21/05/2013. Recommended citation for factsheets for more than one species: BirdLife International (2013) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 21/05/2013.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

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