Data Zone
Justification of Red List category
As a consequence of intense hunting pressure and large-scale habitat destruction, this species has undergone severe declines so that it is now restricted to small and disconnected forest remnants. A successful reintroduction programme has helped to partially offset the decline in this species; the population however remains very small. It is therefore listed as Endangered.
Population justification
A systematic survey using line transects and camera-trapping in Vale Nature Reserve in 2013 found a population of 325 individuals (Alves et al. 2017a). This roughly equates to 215 mature individuals. The authors extrapolate that the adjacent Sooretama Biological Reserve could hold a population of roughly equal size; however they assume that there is no connectivity between both populations as the highway separating the reserves is likely acting as a barrier to dispersal (Alves et al. 2017a). Further population estimates include 33 individuals (equivalent to 22 mature individuals) in Descobrimento National Park and at least 15 individuals (equivalent to 10 mature individuals) in Una Biological Reserve (Phalan et al. 2020), with an unknown, though likely small, number of individuals at other occupied sites. An extrapolation of the global population based on the findings from Vale Nature Reserve was deemed impossible due to local differences in occupancy rates, carrying capacity and hunting pressure (Alves et al. 2017a). It is however assumed that the forests of Vale and Sooretama combined hold c.90% of the global population (ICMBio 2018). Based on this assumption, the global population is here estimated to number 480 mature individuals.
Trend justification
Formerly widespread, the species has undergone drastic declines in the past and is now restricted to remaining fragments of Atlantic Rainforest in east Brazil. The main drivers of the decline appear to be hunting pressure and habitat destruction. Between 2000 and 2021, c.20% of tree cover has been lost within the species' original range (Global Forest Watch 2022, using Hansen et al. [2013] data and methods disclosed therein). This equates to a rate of tree cover loss of 25% over the past three generations (27.6 years). Even though the exact impact of hunting has not been quantified, it is likely that population declines exceeded 30% over the past three generations, with local extinctions in large parts of the range.
Although the population is now largely restricted to protected areas and locally stable or even increasing as a consequence of intense conservation actions and reintroductions, illegal hunting is still ongoing and assumed to be the most severe threat now (ICMBio 2018, Bernardo 2020, Phalan et al. 2020). Even though exact data on the population trend are lacking it is therefore assumed that the population declines are ongoing, albeit at a slower rate.
Crax blumenbachii was formerly widespread in east Brazil, from Bahia south through Espírito Santo and east Minas Gerais to Rio de Janeiro. Intense hunting pressure and large-scale habitat loss have led to its being restricted to a small number of disjunct sites: The species' stronghold is in the Sooretama Biological Reserve and the adjacent Vale Natural Reserve in Linhares, Espírito Santo (ICMBio 2018). Small populations are further observed in Descubrimento National Park, Una Biological Reserve and Serra do Conduru State Park, Bahia (ICMBio 2018).
There have been no confirmed records of wild birds from Rio de Janeiro since 1963 and none from Minas Gerais since the 1970s; however, captive-bred individuals were reintroduced to Guapiaçu Ecological Reserve in Rio de Janeiro and to Fazenda Macedônia, Peti Reserve and Fechos Ecological Station in Minas Gerais (Silveira et al. 2005, Bernardo 2007, Bernardo and Locke 2014, ICMBio 2018).
The species occupies tall lowland patches of Atlantic Rainforest, where it prefers undisturbed sites in close proximity to streams and water (Bernardo 2020). It may also tolerate disturbed habitats including old secondary and regenerating forest (K. M. Flesher in litt. 2012, Alves et al. 2017b). The diet consists of fruit, buds, seeds and arthropods. It may be polygamous, but this observation may result from differential hunting pressure between the sexes. Males boom mainly in September-October with young hatching in the next couple of months. Typically two (range 1-4) eggs are laid.
Major threats to the species are widespread habitat loss and intense hunting pressure. Virtually all lowland forest north of Rio de Janeiro has been converted to plantations and pastureland, with few fragmented patches remaining which are now largely within protected areas. Currently, it is assumed that hunting is the most severe threat to the species, as it persists even in reserves and is likely to have a detrimental impact on the small, disconnected populations (Silveira et al. 2005, Bernardo 2020, Phalan et al. 2020).
Conservation Actions Underway
CITES Appendix I and protected under Brazilian law. Populations are largely restricted to protected areas now. Over 600 individuals were held in zoos and breeding centres in 2010 (Silveira et al. 2005, Phalan et al. 2020). Since the first releases in 1991, four reintroduction projects have taken place in Minas Gerais (at Fazenda Macedônia, Peti Reserve and Fechos Ecological Station) (Scheres 1993, Simpson et al. 1997, Silveira et al. 2005), where introduced birds are periodically monitored, have a high survival rate and are breeding successfully (Simpson et al. 1997, Brooks and Strahl 2000). In Rio de Janeiro state reintroductions began in 2006 at Guapiaçu Ecological Reserve in the Guapi Assu basin (Bernardo 2007). Birds here are radio-tagged and their survival and movements are monitored (Bernardo et al. 2011). Post-release survival probability is high (75%), though lower (60%) when taking into account deaths before release (Bernardo et al. 2011). An action plan for ex situ conservation of the species has identified the need to expand the captive population and increase collaboration between breeding centres to establish a structured breeding programme (Phalan et al. 2020).
84 cm. Large, mostly black cracid. Male glossy black with white vent and undertail-coverts. Long, curly feathers in crown. Knob and wattle reddish-orange. Black legs. Female black with deep cinnamon-rufous vent and undertail-coverts. Flight feathers finely vermiculated with rufous. Shorter, white-barred crest feathers. No wattles. Pinkish legs. Voice Low woop when foraging, eeee-oooo when disturbed. Hints Usually seen in pairs, but groups of four (presumably family units) have been recorded.
Text account compilers
Hermes, C.
Contributors
Benstead, P., Bianchi, C., Capper, D., Derhé, M., Develey, P., Flesher, K., Sharpe, C.J. & Symes, A.
Recommended citation
BirdLife International (2024) Species factsheet: Red-billed Curassow Crax blumenbachii. Downloaded from
https://datazone.birdlife.org/species/factsheet/red-billed-curassow-crax-blumenbachii on 23/12/2024.
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 23/12/2024.