Evaluation of alternative conservation strategies for the blue-billed curassow Crax alberti in the Middle Magdalena Valley, Colombia


IGOR F. VAL EN CIA,GUSTA V O H. KAT T A N,LEONO R VALENZUELA,LIN A CAR O FERNAND O ARB EL AE Z and GERMAN FORERO-MED IN A


Abstract The blue-billed curassow Crax alberti is an en- demic Colombian species categorized as Critically En- dangered on the IUCN Red List because of the effects of hunting and habitat loss. Conservation and management actions are required to ensure its persistence in the forest remnants across its range. We conducted a population via- bility analysis for a population in the municipality of Yondó, Antioquia, based on data collected in the field and avail- able information on the reproductive ecology of the species. We evaluate seven realistic conservation scenarios by com- paring the effects that changes in mortality from hunting, carrying capacity and initial population size have on the survival probability of the population. Our results indicate that: (1) the studied population is not viable over a 100- year period under current conditions; (2) mortality as a re- sult of hunting and the size of the initial population have the greatest impacts on the mean time to extinction; (3) a strat- egy based on eliminating hunting in the two sites with the largest forest remnants in the landscape could ensure the viability of the population over a 100-year period; and (4) other strategies (i.e. population supplementation with cap- tive-bred individuals, reduction of deforestation in the land- scape) do not guarantee the viability of the population if mortality from hunting remains constant, even at lowlevels. These results confirm the susceptibility of the blue-billed curassowto the threats it faces in this landscape, particularly hunting, and provide information on the conservation ac- tions that could allow this remaining population to prevail in the long term.


Keywords Blue-billed curassow, camera-trap sampling, Colombia, conservation strategies, Crax alberti, occupancy, population viability analysis


Introduction M


ost populations of threatened species require man- agement and conservation actions to ensure their


IGOR F. VALENCIA (Corresponding author, ivalencia@wcs.org), LEONOR VALENZUELA ( LINA CARO and GERMAN FORERO-MEDINA (


orcid.org/0000-0002-4442-4222, orcid.org/0000-0003-0814-3690), orcid.org/0000-0001-9952-7221)


Wildlife Conservation Society, Avenida 5N # 22N-11, Cali, Colombia GUSTAVO H. KATTAN (


orcid.org/0000-0003-4198-773X) Departamento de


Ciencias Naturales y Matemáticas, Pontificia Universidad Javeriana Seccional Cali, Cali, Colombia


FERNANDO ARBELAEZ Fundación Biodiversa Colombia, Bogotá, Colombia


Received 27 April 2021. Revision requested 29 July 2021. Accepted 25 January 2022. First published online 6 February 2023.


recovery and persistence. This is particularly true for vertebrates affected by hunting and habitat loss, two of the major causes of biodiversity loss (Péres, 2001; Urquiza-Haas et al., 2011). However, in many cases conser- vation actions are implemented without previous assess- ments of their potential impacts on a population or an evaluation of their relative effectiveness in comparison to al- ternative strategies. Although for many species or popula- tions such assessments could require data that have not been collected, in some cases it is possible to complement field data with secondary information to evaluate the rela- tive potential impacts of conservation actions. One common approach to assessing such strategies is population viability analysis (Urquiza-Haas et al., 2011), which estimates the probability of a population persisting over time (Morris & Doak, 2003). Such an analysis allows us to obtain the survival probability (P[Survive]) for a given period of time and to determine the viability of the population under alternative conservation scenarios. It thus supports decision-making regarding the most effective actions based on demographic information of the popula- tion, ecological parameters of the species and stochastic variables that affect the population. This type of analysis has been widely used to address conservation problems in- volving several species, including cracids (Martínez-Morales et al., 2009; São Bernardo et al., 2014). Nonetheless, popula- tion viability analyses, as well as sensitivity analyses that as- sess the impacts of variable vital rates on population growth, have limitations and should be implemented and inter- preted with care (Manlik et al., 2018). The perturbations evaluated should be realistic and feasible to implement, the parameters used should be presented clearly, with levels of confidence to ensure robustness and reliability for decision-making, and population viability analysis models should be repeatable and reproducible (Morrison et al., 2016; Manlik et al., 2018). The cracids are one of the most threatened bird families


in the Neotropics (Silva & Strahl, 1997). The blue-billed curassow Crax alberti is endemic to Colombia. Historically it occurred in the northern dry forests of Colombia and to the south in humid forests of the Middle Magdalena


This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited. Oryx, 2023, 57(2), 239–247 © The Author(s), 2023. Published by Cambridge University Press on behalf of Fauna & Flora International doi:10.1017/S0030605322000060


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