The main goal of this project is to better understand the ecology, distribution, and population trend of the Black-headed Bushmaster (Lachesis melanocephala) and to secure its preservation through ex situ conservation.

In order to achieve our main goal we will study basic aspects of the natural history of the Black-headed Bushmaster, but also its habitat requirements, especially through telemetry studies and a detailed description of the vegetation where it is found.

The setup of a conservation breeding program, this to ensure the survival of the species.

Natural History

The name of the Black-headed Bushmaster (Lachesis melanocephala) or Plato Negro, it’s local Spanish name, are derived from the Greek Lachesis which means ‘the personification of fate’, melanos meaning ‘black’ and cephalo meaning ‘head’. It is one of Costa Rica’s largest pitvipers, and one of the world’s largest venomous snakes, they can reach a total length of 240 cm, with males growing larger than females. What makes snakes in the genus ‘Lachesis’ special is that they are oviparous, they lay eggs which are incubated in the environment, this is a feature that is uncommon in pitvipers from the Americas. The eggs are laid in abandoned mammal burrows and are guarded by the female.

Still little is known about the natural habits of this species in the wild, but it has been recorded to be terrestrial, crepuscular and nocturnal.

The Black-headed Bushmaster is the rarest of all bushmasters, this due to its limited distribution range. The range is from the central Pacific region, with an old record from Puriscal, all the way south to the Osa Peninsula and adjacent areas, from sealevel up to 1600 m elevation. The species has been reported in Panama, but like everywhere throughout its distribution, reports are scarce.


The team of Plato Negro Ecology and Conservation has been working with Black-headed Bushmasters since 2012 and since 2015 has conducted telemetry studies on the species. A better understanding of the natural history of the species benefits a good conservation strategy for the Black-headed Bushmaster.

Black-headed bushmasters are infamous for being large, venomous and aggressive snakes. By our experience in the field, having worked with several individuals, we conclude that latter statement is more than incorrect. Dispelling myths by involving and educating local communities and landowners, is the key for protecting this species against extinction.

Preservation and restoration of habitat is essential to the conservation of the species and all other organisms in it’s environment.

A captive breeding program is being setup to ensure the species’ survival in the future and to ensure genetic diversity for wild populations.



In this section we share with you all the papers concerning Black-headed Bushmasters, published in the past by various authors:

  • Campbell, J.A., & Lamar, W.W. (1989). The Venomous Reptiles of Latin America. Ithaca, USA: Cornell University Press.
  • Campbell, J. A., and W. W. Lamar. 2004. The Venomous Reptiles of the Western Hemisphere. 2 vols. Cornell University Press, Ithaca, New York. 870 pp
  • De Plecker, R., & Dwyer, Q. (2020). First Breeding of the Black-headed Bushmaster (Lachesis melanocephala) in Costa Rica. Herpetological Review, 51(1), 57-64.
  • Dwyer, Q., and M. Perez. 2009. Lachesis melanocephala. Herpetol. Rev. 40:114.
  • Eatherly, D. 2015. Bushmaster: Raymond Ditmars and the Hunt for the World’s Largest Viper. Arcade Publishing. New York. 320 pp.
  • González-Maya, J.F., Castañeda, F., González, R., Pacheco, J., & Ceballos, R. (2014). Distribution, range extension and conservation of the endemic Black-headed Bushmaster (Lachesis melanocepahala) in Costa Rica and Panama. Herpetological Conservation and Biology, 9(2), 369-3
  • Jaramillo, C., L. D. Wilson, R. Ibáñez, and F. Jaramillo. 2010. The herpetofauna of Panama: distribution and conservation status. In J. H. Townsend (ed.), Conservation of Mesoamerican Amphibians and Reptiles, pp. 604–671. Eagle Mountain Publishing, Eagle Mountain, Utah.
  • Madrigal, M., Sanz, L., Flores-Díaz, M., Sasa, M., Núñez, V., Alape-Girón, A., & Calvete, J.J. (2012). Snake venomics across genus Lachesis. Ontogenetic changes in the venom composition of Lachesis stenophrys and comparative proteomics of the venoms of adult Lachesis melanocephala and Lachesis acrochorda. Journal of Proteomics, 77, 280-297.
  • Ripa, D. (1994). The reproduction of the Central American bushmaster (Lachesis muta stenophrys) and the blackheaded bushmaster (Lachesis muta melanocephala) for the first time in captivity. Bulletin of the Chicago Herpetological Society, 29, 165-183.
  • Ripa, D. (2004). The Bushmasters (Genus Lachelis Daudin, 1803): Morphology in Evolution and Behaviour. Wilmington, USA: Ripa Ecologica.
  • Savage, J.M. (2002). Amphibians and Reptiles of Costa Rica: A Herpetofauna between Two Continents between Two Seas. Chicago, USA: The University of Chicago Press.
  • Solórzano, A. (2004). Serpientes de Costa Rica: Distribución, taxonomía e historia natural. Heredia, Costa Rica: Instituto Nacional de Biodiversidad (INBio).
  • Solórzano, A., and M., Sasa (2020). Redescription of the snake Lachesis melanocephala (Squamata: Viperidae): Designation of a neotype, natural history, and conservation status. Rev. Biol. Trop. (Int. J. Trop. Biol.). Vol. 68(4): 1384-1400, December 2020.
  • Zamudio, K. R., and H. W. Greene. 1997. Phylogeography of the bushmaster (Lachesis muta: Viperidae): Implications for neotropical biogeography, systematics, and conservation. Biol. J. Linn. Soc. 62:421–442.