Growth rates of black caiman (Melanosuchus niger) in the Rupununi region of Guyana

in Amphibia-Reptilia
Restricted Access
Get Access to Full Text
Rent on DeepDyve

Have an Access Token?

Enter your access token to activate and access content online.

Please login and go to your personal user account to enter your access token.


Have Institutional Access?

Access content through your institution. Any other coaching guidance?


We conducted a study of black caiman (Melanosuchus niger) growth rates using data from a long-term mark-recapture study carried out in the Rupununi region of Guyana between 2005 and 2015. In contrast to previous studies, growth rates of black caiman declined with increasing size and this decline occurred more rapidly for females. Size-at-age models predicted that males and females reach asymptotic sizes of 178.2-189.0 cm SVL and 140.1-143.4 cm SVL, respectively. Our results suggest that growth rates of black caiman in the Rupununi region follow the same general patterns as for other crocodilians, and that disparities with previous black caiman studies may be largely related to density-dependent factors, among other possibilities. However, future studies that include large black caiman of known ages are needed to validate our findings.


Publication of the Societas Europaea Herpetologica



CamposZ.MagnussonW.E.MarquesV. (2013): Growth rates of Paleosuchus palpebrosus at the southern limit of its range. Herpetologica 69: 405-410.

CamposZ.MouraoG.CoutinhoM.MagnussonW.E. (2014): Growth of Caiman crocodilus yacare in the Brazilian Pantanal. PLoS ONE 9: e89363.

ChabreckR. (1963): Methods of capturing, marking and sexing alligators. Proc. Annu. Conf. Southeast. Assoc. Game Fish Comm. 17: 7-50.

ChabreckR.JoanenT. (1979): Growth rates of American alligators in Louisiana. Herpetologica 35: 51-57.

Da SilveiraR.MagnussonW.E.ThorbjarnarsonJ.B. (2008): Factors affecting the number of caimans seen during spotlight surveys in the Mamirauá Reserve, Brazilian Amazonia. Copeia 2008: 425-430.

Da SilveiraR.CamposZ.ThorbjarnarsonJ.MagnussonW.E. (2013): Growth rates of black caiman (Melanosuchus niger) and spectacled caiman (Caiman crocodilus) from two different Amazonian flooded habitats. Amphibia-Reptilia 34: 437-449.

DelanyM.WoodwardA.R.KiltieR.A.MooreC.T. (2011): Mortality of American alligators attributed to cannibalism. Herpetologica 67: 174-185.

FernandezM. (1999): Cannibalism in Dungeness crab Cancer magister: effects of predator-prey size ratio, density, and habitat type. Mar. Ecol. Prog. Ser. 182: 221-230.

HerronJ. (1991): Growth rates of black caiman Melanosuchus niger and spectacled caiman Caiman crocodilus, and the recruitment of breeders in hunted caiman populations. Biol. Conserv. 55: 103-113.

HopperK.CrowleyP.H.KielmanD. (1996): Density dependence, hatching synchrony, and within-cohort cannibalism in young dragonfly larvae. Ecology 77: 191-200.

HuttonJ. (1987): Growth and feeding ecology of the Nile crocodile Crocodylus niloticus at Ngezi, Zimbabwe. J. Anim. Ecol. 56: 25-38.

JacobsenT.KushlanJ.A. (1989): Growth dynamics in the American alligator (Alligator mississippiensis). J. Zool., Lond. 219: 309-328.

MagnussonW. (2012): Estimating age from recapture data: the importance of data exploration. Croc. Spec. Group Newsl. 31: 13-16.

PetraitisP.BeaupreS.J.DunhamA.E. (2001): ANCOVA: nonparametric and randomization approaches. In: Design and Analysis of Ecological Experiments, p.  116-133. ScheinerS.GurevitchJ., Eds, Oxford University Press, New York.

RichardsF. (1959): A flexible growth function for empirical use. J. Exp. Bot. 10: 290-300.

RootesW.ChabreckR.H.WrightV.I.BrownB.W.HessT.J. (1991): Growth rates of American alligators in estuarine and palustrine wetlands in Louisiana. Estuaries 14: 489-494.

RootesW.ChabreckR.H. (1993): Cannibalism in the American alligator. Herpetologica 49: 99-107.

SaalfeldD.WebbK.K.ConwayW.C.CalkinsG.E.DuguayJ.P. (2008): Growth and condition of American alligators (Alligator mississippiensis) in an inland wetland of east Texas. Southeast. Nat. 7: 541-550.

ThorbjarnarsonJ. (2010): Black caiman Melanosuchus niger. In: Crocodiles: Status Survey and Conservation Action Plan, p.  29-39. ManolisS.StevensonC., Eds, IUCN Crocodile Specialist Group, Darwin, Australia.

ThorbjarnarsonJ.McIntoshP.E. (1987): Notes on a large Melanosuchus niger skull from Bolivia. Herpetol. Rev. 18: 49-50.

TuckerA.LimpusC.J.McDonaldK.R.McCallumH.I. (2006): Growth dynamics of freshwater crocodiles (Crocodylus johnstoni) in the Lynd River, Queensland. Aust. J. Zool. 54: 409-415.

VallejoA.RonS.AsanzaE. (1996): Growth in Melanosuchus niger and Caiman crocodilus at Zancudococha and Cuyabeno, Ecuadorian Amazon. In: Proceedings of the 13th Working Meeting of the IUCN/SSC Crocodile Specialist Group, p. 91-93. IUCN Crocodile Specialist Group, Gland, Switzerland.

WatkinsG. (2002): Black caiman surveys in the Rupununi. Croc. Spec. Group Newsl. 21: 15-16.

WebbG.BuckworthR.ManolisS.C. (1983): Crocodylus johnstoni in the McKinlay River area, N.T. III. Growth, movement and the population age structure. Aust. Wildlife Res. 10: 383-401.

WebbG.MesselH.CrawfordJ.YerburyM.J. (1978): Growth rates of Crocodylus porosus (Reptilia: Crocodilia) from Arnhem Land, northern Australia. Aust. Wildlife Res. 5: 385-399.

WilkinsonP.RhodesW.E. (1997): Growth rates of American alligators in coastal South Carolina. J. Wildlife Manage. 61: 307-402.


  • Relationship between growth rate and geometric mean snout-vent length for 74 male (top) and 17 female (bottom) black caiman captured and recaptured in the Rupununi region of Guyana between 2005 and 2015. Straight lines represent linear regression best-fit equations and lines connecting dots represent individual caiman that were recaptured more than once.

    View in gallery
  • Relationship between snout-vent length and age for male (solid line) and female (dashed line) black caiman across three different models.

    View in gallery


Content Metrics

Content Metrics

All Time Past Year Past 30 Days
Abstract Views 20 20 12
Full Text Views 14 14 14
PDF Downloads 3 3 3
EPUB Downloads 0 0 0