Cooperative Fish and Wildlife Research Units Program: Mississippi
Education, Research and Technical Assistance for Managing Our Natural Resources

Gallardo, J.C., F.J. Vilella, and M.E. Colvin. 2019. A seasonal population matrix model of the Caribbean Red-tailed Hawk Buteo jamaicensis jamaicensis in eastern Puerto Rico. Ibis 161:459-466.


A critical, and often missing, component in conservation and management are estimates of life history parameters and their role in animal population trajectories. We developed a periodic population matrix model of the Red-tailed Hawk in eastern Puerto Rico to describe the influence of early life-stages on population growth in the lower and upper forests of the Luquillo Mountains. Model results indicated the Red-tailed Hawk populations exhibited a positive discrete rate of growth in the study region (upper forest: λ = 1.05; lower forest: λ = 1.27). Further, adult survival was the most important parameter influencing population growth (elasticity upper forest = 0.86, elasticity lower forest = 0.53). Besides adult survival, nestling survival had a greater influence in λ than for other life-stages (sensitivity lowlands = 0.46, sensitivity highlands = 0.48), highlighting the importance of this life stage to the growth rate of Red-tailed Hawks in our study area. Our approach may serve as a conceptual and analytical modeling framework to quantify the influence of early life-stages on population growth in other avian species.