|Scientific Name:||Houbaropsis bengalensis|
|Species Authority:||(Gmelin, 1789)|
Eupodotis bengalensis ssp. bengalensis (Gmelin, 1789) — Sibley and Monroe (1990, 1993)
Otis bengalensis Gmelin, 1789
|Taxonomic Source(s):||del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.|
|Identification information:||66-68 cm. Mostly black bustard with largely white wings. In flight, wings entirely white except for black tips. Female and immature are buff-brown to sandy-rufous, and have buffish-white wing-coverts with fine, dark barring. Similar spp. Lesser Florican Sypheotides indica is smaller and longer-necked. Male has spatulate-tipped head plumes, white collar across upper mantle and white wing-coverts. Female has more prominent pale wing-coverts. Voice Croaks and strange, deep humming during display. Sometimes shrill metallic chik-chik-chik when disturbed. Hints Search grasslands during March-May when displaying males are most conspicuous.|
|Red List Category & Criteria:||Critically Endangered A3bcd+4abcd ver 3.1|
|Reviewer(s):||Butchart, S. & Symes, A.|
|Contributor(s):||Chamnan, H., Evans, T., Gray, T., Hogberg, S., Tordoff, A.W., Packman, L., Mahood, S. & vanZalinge, R.|
|Facilitator/Compiler(s):||Benstead, P., Bird, J., Butchart, S., Calvert, R., Crosby, M., Davidson, P., Peet, N., Symes, A., Taylor, J., Tobias, J., Allinson, T, Martin, R & Ashpole, J|
This bustard has a very small, declining population; a trend that has recently become extremely rapid and is predicted to continue in the near future, largely as a result of the widespread and on-going conversion of its grassland habitat for agriculture. It therefore qualifies as Critically Endangered.
|Previously published Red List assessments:|
|Range Description:||The species has two disjunct populations, one in the Indian Subcontinent, the other in South-East Asia (BirdLife International 2001). The former occurs from Uttar Pradesh, India, through the terai of Nepal, to Assam and Arunachal Pradesh, India, and historically to Bangladesh. It has declined dramatically and only survives in small, highly fragmented populations. Declines have apparently continued in Nepal, even inside the protected Royal Chitwan National Park (Baral et al. 2003), but they may have stabilised in India (Rahmani 2001). Surveys and interviews with staff at four protected areas in the North Bank area of Assam suggest that the species has been largely absent from three of them since 2000 (Brahma and Lahkar 2009). Manas National Park in Assam currently holds the largest number of individuals in India, in the 1990s the population was thought to be 80-100 birds but is now likely to be lower owing to habitat loss (Choudhury 2011). An estimate from 2007 put the Nepalese population at just 28-36 mature individuals (restricted to a few widespread sites) (Poudyal 2007), down from 32-60 individuals in 2001. Recent intensive survey effort in Nepal has recorded 47 individuals in and around Koshi Tappu Wildlife Reserve, including 14 birds outside any protected area and an estimate of 60 individuals in total (Baral et al. 2013). This is almost double the numbers from a survey of the area in 2012 when around 12 pairs were estimated (Baral et al. 2012), but this is due to a more rigorous survey methodology (Baral et al. 2013). Previously this site was thought to only support a few individuals (Baral et al. 2003). This is the largest population in Nepal (Baral et al. 2013) and if numbers from the 2007 survey are still accurate this would put the total number of mature individuals in Nepal at 75-96. |
The South-East Asian population occurs in Cambodia and may be extant in southern Vietnam. The population in the Tonle Sap region, which supports the vast majority of the population of Cambodia, was estimated at between 312 and 550 (95% CI) based on surveys in 2012, with only 216 displaying males recorded (C. Packman in litt. 2013, Packman et al. 2014). This represents a 44% decrease from the previous survey in 2005, and a minimum of 294 displaying males had been recorded in 2007 (Gray et al. 2009). If the population continues to decline at the current rate, it may become extinct in Cambodia within 10 years (Packman et al. 2014). More than 50% of the Cambodian population occurs on seasonally inundated grasslands within Kompong Thom province (Gray et al. 2009). This estimate, based on extent of available habitat in 2005 and known habitat loss between 2005 and 2007, represents a rapid decline owing to habitat loss, from a projected 3,000 individuals in 1997 (T. Gray, T. Evans and Hong Chamnan in litt. 2006). Given accelerating post-2005 grassland loss of 28% within 10 grassland blocks holding 75% of the estimated population (Gray et al. 2009), and a further 11% of habitat lost in four protected areas in 2008 (Evans et al. 2009), projected rates of decline will equate to over 80% during a three generation period (T. Gray, T. Evans and Hong Chamnan in litt. 2006). Recent assessment of habitat loss indicates that it has indeed been widespread and extensive between 2005 and 2012, and a number of sites identified as having blocks of grassland in excess of 10 square kilometers now contain little or no grassland (C. Packman in litt. 2013). Kouk Preah Beung Trea, San Kor and Stoung-Chikraeng, all largely in Kompong Thom province, support the largest number of birds within Cambodia (54, 53 and 43 displaying males respectively) (Packman et al. 2014). Annual monitoring of Bengal Florican populations in Bengal Florican Conservation Areas (BFCAs) and adjacent areas in Cambodia during March-April 2008-11 indicates that whilst populations in some protected areas are stable, in other locations population declines are ongoing. Outside of protected areas there is likely to be very little suitable grassland habitat remaining (Mahood et al. 2012).
Native:Cambodia; India; Nepal; Viet Nam
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||The population in Cambodia was estimated at 294 displaying males or c. 600 individuals in 2009 (Gray et al. 2009a), but recently an extensive survey has reported a total of only 432 individuals (95% CI 312-550) (C. Packman in litt. 2013, Packman et al. 2014). 75-96 individuals remain in Nepal (Baral et al. 2013). No recent estimates are known from India but the total global population for this species is likely to fall in the range 250-999 mature individuals. This equates to 375-1,499 individuals in total, rounded here to 350-1,500 individuals.|
Trend Justification: A very rapid decline in the global population is estimated to have occurred over the last three generations, based on figures from Cambodia. Current and projected rates of decline in the Cambodian population alone equate to a decline in the global population exceeding 80% in three generations (T. Gray in litt. 2006).
|Current Population Trend:||Decreasing|
|Habitat and Ecology:||It inhabits lowland dry, or seasonally inundated, natural and semi-natural grasslands, often interspersed with scattered scrub or patchy open forest. Most Indian populations appear to be resident. In Cambodia, it is known to make relatively local seasonal movements in response to the flooding regime of the Tonle Sap lake: in the dry season, the species breeds in grasslands in the inundation zone of the lake; it then moves to nearby open forest areas during the wet season. During the breeding season males preferentially select habitats related to low-intensity human activity, chiefly burned grassland, whereas females primarily select unburned grassland but also use unburned, uncultivated grassland in dry-season rice head-ponds (Gray et al. 2009), although anecdotal evidence suggests that eggs are laid in small pockets of medium to tall grass in recently burnt areas (R. van Zalinge, pers. obs.).|
|Continuing decline in area, extent and/or quality of habitat:||Yes|
|Generation Length (years):||10.3|
|Movement patterns:||Full Migrant|
The key threats are the extensive loss and modification of grasslands through drainage, conversion to agriculture and plantations, overgrazing, inappropriate cutting, burning and ploughing regimes, heavy flooding, invasion of alien species, scrub expansion, dam construction and inappropriate and illegal development (Brahma and Lahkar 2009, Evans et al. 2009, van Zalinge et al. 2009). In particular, the spread of dry season rice cultivation in Cambodia is rapidly converting existing grassland habitat (Packman et al. 2014). An increase in the area of scrub vegetation between 1995/1996 and 2005 was responsible for 65% of grassland loss in Cambodia (Packman et al. 2013). Land sales and concessions are often pushed through despite resistance from local villagers (Evans et al. 2009). Excessive hunting for sport and food may have triggered its decline, but owing to advocacy and law enforcement is no longer a serious threat, at least in Cambodia. In South Asia, most populations are small, isolated and vulnerable to local extirpation. Other threats may include human disturbance and trampling of nests by livestock. Detailed research into the species's ecology in Cambodia demonstrated that the effects of human disturbance are weak and annual burning is important for maintaining suitable habitat, supporting the idea that community-based grassland management that maintains traditional agricultural practices will benefit the species. This has implications for management in South Asia, where remaining (and declining) populations are largely confined to strict protected areas in which such practices may not be occurring (Gray et al. 2007). Further study has revealed that, whilst burned grassland is selected by males during the breeding season, unburned grassland and other habitats providing cover are selected by females, demonstrating the need for management that provides a variety of habitats (Gray et al. 2009).
Conservation Actions Underway
CITES Appendix I. Several populations occur within protected areas, the most important being the Bengal Florican Conservation Area (BFCA) network in Cambodia (see Mahood et al. 2012), Chitwan National Park, Royal Bardia National Park and Sukla Phanta Wildlife Reserve, Nepal, Kaziranga, Dibru-Saikhowa and Dudwa National Parks, India. Tiny, perhaps unsustainable populations may still remain at Ang Trapeang Thmor Sarus Crane Reserve, Cambodia and within the Mekong Delta at Boeung Prek Lapouv Sarus Crane Reserve, Cambodia and Tram Chim National Park, Vietnam. A PhD research project investigating movements and habitat requirements in the non-breeding season began in 2007 and at least 19 birds were fitted with satellite or radio transmitters (Packman 2008, 2009), the data from which have revealed previously unknown non-breeding sites (Packman 2009). The Wildlife Conservation Society, BirdLife International and their government partners are engaged in a programme of conservation activities in the Tonle Sap floodplain of Cambodia, aimed at reducing habitat loss and hunting pressure on the species (A. W. Tordoff in litt. 2007). Achievements so far include the designation of 173 km2 of breeding and 138 km2 of non-breeding habitat as Bengal Florican Conservation Areas (BFCAs). Populations in the BFCAs and in adjacent areas have been monitored annually since 2008 using a survey which employs a randomised sampling design to measure occupancy of 1 km2 squares by displaying males which allows results to be extrapolated within and across sites to obtain accurate population and trend data. These data indicate that the population is probably stable at some BFCAs and possibly declining in others and in adjacent areas (van Zalinge et al. 2009, 2010, Mahood et al. 2012). Suitable habitat in BFCAs continues to be lost to various threats, including the expansion of dry season rice cultivation and dam construction (van Zalinge et al. 2010), although overall habitat loss outside BFCAs has been much greater.
Work is on-going to maintain effective management structures for these areas and build constituencies of support for their conservation among local stakeholders. Official patrol teams are now operating in Kampong Thom and Siem Reap, and in both provinces the Forestry Administration, working through provincial commissions, has already halted several proposed developments which would otherwise have destroyed vital breeding habitat (Eames 2007, van Zalinge et al. 2009, 2010, Mahood et al. 2012). Changes in land use in the Tonle Sap floodplain and in the BFCAs in particular are also monitored with the aid of aerial and/or satellite images (Gray et al. 2009, van Zalinge et al. 2009). When land encroachment in the BFCAs is detected through patrols or satellite-monitoring, WCS facilitates meetings between the parties concerned to resolve disputes and reverse encroachment. An in-depth socio-economic study has been conducted by the Centre d'Etude et de Développement Agricole Cambodgien. The report highlights the economic benefits local communities derive through the traditional use of grasslands and is used to build support among key decision makers and local communities. An awareness programme covering 71 villages and over 3,200 people was conducted in 2008/9 and outreach activities in schools and villages are ongoing. Training in selected villages was conducted to improve agricultural systems and reduce the immediate pressure on grasslands from people wanting to convert grasslands into agriculture (BirdLife International 2009). Villagers receive financial rewards for reporting nests which they incidentally find as a deterrent against collecting and eating the eggs; finders receive an additional financial reward if the nest fledges successfully, although nest-finders are discouraged from protecting the nests directly to reduce accidental disturbance to birds (van Zalinge et al. 2009, van Zalinge et al. 2010, Mahood et al. 2012).
At the four breeding season BFCAs, community management committees have been established to act as intermediaries between WCS, government partners and the communities, they assist in awareness raising, patrolling and reporting illegal activities in the BFCAs. At one of the BFCAs rice is purchased at a premium from local farmers abiding by conservation agreements under a wildlife-friendly rice initiative and community members gain an additional income from acting as guides to birdwatchers visiting the site through the Sam Veasna Centre. These activities appear to be having some early success in arresting the rapid decline of the species in Cambodia, but their long-term outcome remains to be seen.
In 2012 a Darwin Initiative project was initiated to look at the species's distribution and habitat requirements in India and Nepal (Barber 2013). In Nepal, two male birds were satellite tagged in April 2013 (Barber 2013), followed by two females and a male in 2014 and three males in India in 2014 (Barber 2014). As a result of the tagging work, conservationists will be able to identify important areas for the species and propose suitable management regimes. Trial habitat plots have also been established to understand habitat preferences.
Conservation Actions Proposed
Continue annual monitoring of the population in the BFCAs, Cambodia, and replicate the monitoring protocol in key sites in India and Nepal. Conduct research on Bengal Florican breeding productivity, and habitat utilisation in breeding and non-breeding BFCAs. Introduce a protected area management regime, including appropriate rotational burning, grazing and cutting based on research findings. Promote grassland conservation awareness initiatives in all range countries. Strengthen the legal protection for existing BFCAs and expand the network (van Zalinge et al. 2009, 2010, Packman et al. 2014). Continue surveys for populations, particularly in Koshi Tappu Wildlife Reserve and Koshi Barrage, Nepal (Poudyal 2007). Identify additional important sites for birds in the non-breeding season in Cambodia. Land acquisition outside the BFCA network and/or conservation concessions may be required to protect important areas for the species (Handschuh 2013, Packman et al. 2014). Extend, upgrade and link protected areas in India and Nepal, and establish new ones. Devise and promote a conservation strategy for all Asian bustards. Share best practice guidelines for management of small bustards in grassland habitats across Europe and Asia.
|Citation:||BirdLife International. 2016. Houbaropsis bengalensis. The IUCN Red List of Threatened Species 2016: e.T22692015A93333629.Downloaded on 22 June 2017.|