VU
Great Curassow Crax rubra



Justification

Justification of Red List Category
A rapid population decline is ongoing owing to hunting pressure and habitat loss and fragmentation. If these declines are found to be even greater than is currently suspected it may require further uplisting to Endangered.

Population justification
The population size is estimated at 50,000-499,999 by Partners in Flight (2019), however previous estimates placed the number of mature individuals between 6,700-40,000 (O. Jahn in litt. 2009). It is here therefore tentatively assumed that the population size is ~50,000 mature individuals; however further confirmation of this estimate is required.

Trend justification
This species is suspected have undergone rapid declines during the past three generations (25 years) owing to hunting pressure and habitat loss and fragmentation, and these declines are predicted to continue. Forest decline throughout its range has been extensive during the past 25 years with over 12% of forest areas lost throughout the period (Tracewski et al. 2016). Subspecies griscomi is similarly declining throughout its range on Cozumel Island under continued increasing pressure (Caballero and Martínez-Morales 2006).

Distribution and population

Crax rubra has a wide but now highly fragmented distribution from San Luis Potosí, Tamaulipas, Querétaro, Hidalgo, Puebla, Veracruz, Oaxaca, Tabasco, Chiapas and the Yucatán peninsula, Mexico (Howell and Webb 1995, F. González-García in litt. 1998, M. Martínez-Morales in litt. 1998), south through Belize, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica and Panama to west Colombia (Pacific lowlands east to the Gulf of Urabá and the upper Sinú valley) and, very rarely, west Ecuador (Sibley and Monroe 1990, R. S. Ridgely in litt. 1998). The distinctive race griscomi is restricted to Cozumel Island off Mexico, where an estimated 300 individuals remain (Martínez-Morales 1996) and it is thought to have declined (Caballero and Martínez-Morales 2006). It has undergone a considerable (and continuing) decline, becoming uncommon to rare or locally extinct throughout much of its range. In Ecuador there are perhaps fewer than 100 individuals occurring in three protected areas (J. Freile in litt. 2009), with very few recent reports of the species (J. Freile in litt. 2012). Healthy populations occurred in the Chimalapas region of Oaxaca, but the effects of extensive fires in 1998 on the species are largely unknown (A. G. Navarro in litt. 1998). Recent assessments have however identified chicks and juveniles in the region, suggesting a reproductive population in the region (Pérez-Irineo and Santos-Moreno 2017). However, it has recovered or remains relatively common in areas with legal protection or where it is not hunted, and populations are still stable in isolated and well protected parts of Guatemala and Nicaragua (del Hoyo 1994).

Ecology

It is restricted to undisturbed humid evergreen forest (also seasonally dry forest in some areas) and mangroves although there are reports that it tolerates limited disturbance (Radachowsky et al. 2004). The species has been seen to utilise secondary forest in areas absent of hunting (Whitworth et al. 2018). Subspecies griscomi displays a particular preference for the tropical semi-deciduous forest of Cozumel Island however (Martínez-Morales 1999). It is primarily a lowland species but has been recorded at altitudes of up to 1,900 m in Panama and on the northern slope of Sierra de las Minas, Guatemala (E. H. Baur in litt. 2012). The species has been observed singly, in pairs and in small groups and is typically frugivorous, although it has been noted to infrequently glean foliage and litter for invertebrates and small vertebrates (Vannini and Rockstroh 1997).  Nests are typically small and within 5 m of the ground; clutches normally comprise two eggs (Vannini and Rockstroh 1997).

Threats

It is widely hunted for food, sport and illegal pet traffic which whilst strongly prohibited in Ecuador, Nicaragua and El Salvador, is permitted for subsistence in Costa Rica, Colombia, Guatemala, Honduras, Panama and Mexico, and for all purposes in Belize (Miller and Miller 1997, Brooks and Strahl 2000, Brooks 2006). It is further threatened by severe habitat loss and fragmentation (del Hoyo 1994, Arguedas et al. 1997, Radachowsky and Ramos 2004, Radachowsky et al. 2004). It rapidly disappears when logging roads are built into previously inaccessible forests (del Hoyo 1994). Extensive fires, such as those in Oaxaca, Mexico in 1998, may be a threat to habitat quality, and some birds are captured as pets. Additional potential threats to race griscomi include hurricanes and the introduction of invasive species (Caballero and Martínez-Morales 2006).

Conservation actions

Conservation Actions Underway
CITES III in Guatemala, Costa Rica, Honduras and Colombia (del Hoyo 1994). It occurs in a number of protected areas including Santa Rosa, Rincón de la Vieja and Corcovado National Parks in Costa Rica (del Hoyo 1994). A captive breeding and reintroduction project is taking place in secondary forest on the Nicoya Peninsula, Costa Rica with 94 birds released between 2000-2004 (Zepeda 2006).

Conservation Actions Proposed
Survey populations and ascertain trends at known sites. Research land-use effects on the species and its habitat. Effectively protect national parks where the species occurs. Enforce hunting restrictions (and ban hunting in countries where it is currently permitted), and introduce educational campaigns to reduce hunting pressure.

Identification

This species is the largest of the Curassows; Male: 87-92 cm, 3600-4800 g; Female: 78-84 cm, 3100-4270 g (del Hoyo and Kirwan 2020). The male has a black body with a blue-green reflection to its feathers, snowy white abdomen, black legs and a very well developed crest, strongly curled forward. The tail is black whilst outer feathers are often tipped with white, its eyes are brown whilst the bill is black with a yellow base. A conspicuous yellow knob on the upper mandible grows particularly intense during breeding season (Throp 1964). Females differ entirely to the males and adopt one of three morphs; barred, dark or red. Dark and barred morphs are unknown in the South American part of the range whilst the red morph does not occur in Mexico (del Hoyo and Kirwan 2020). The crest, more spectacular than the males', and head are barred with black and white, the lower back is chestnut brown, under parts cinnamon (Throp 1964). Race griscomi smaller, with slight colour differences in females (del Hoyo and Kirwan 2020).

Acknowledgements

Text account compilers
Everest, J.

Contributors
Baur, E.H., Benstead, P., Brooks, D., Derhé, M., Freile, J., González-García, F., Isherwood, I., Jahn, O., Martínez-Morales, M., Navarro, A.G., Ridgely, R.S., Rios, M., Sandoval, L., Sharpe, C.J. & Symes, A.


Recommended citation
BirdLife International (2022) Species factsheet: Crax rubra. Downloaded from http://www.birdlife.org on 22/05/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 22/05/2022.