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Published: 2003

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Despite 34 years of recovery efforts, the Puerto Rican Parrot continues to face a high risk of extinction. In 2002 the population count was estimated at 20-24 individuals, similar to post-hurricane Hugo counts (23) and close to the all time low count of 17-19 individuals in 1973. In light of this situation, coupled with discussions about establishing a second population in the karst region in north-central Puerto Rico, I reviewed cumulative demographic data collected over the past 13 years and conducted a population viability analysis to update the status and recovery outlook of the species. I used program Vortex to assess the status of the species and conducted a sensitivity analysis to assess the relative importance of selected parameters in the demography of the species. Basic Scenario model projections over 100 years were of a declining population (stoc. r = -0.066). Within 10 years the mean population (across extant populations) dropped from 40 to 24 individuals, and within 20 years, to 15 individuals. The persistence of the population was 0 and the mean time to extinction was 37.4 years. Sensitivity analyses indicated that almost none of the parameter values used in the model scenarios yielded a positive, mean stochastic growth. Low juvenile mortality (32% for age 0-1) produced the only positive average stochastic growth rate (r>0.02). Relative to the Basic Scenario model, the population grew only when productivity levels exceeded 2.5. Productivity levels recorded from 1990-95 (1.88 young fledged/active nest) and 1996-2002 (1.23young fledged/active nest) resulted in a steady population decline with very low persistence (0-3%). At the average productivity since 1990 (1.56 young fledged /active nest), supplementation temporarily boosted the mean population size. Once supplementations stopped, mean population size declined. The population continued to grow only when supplementation was coupled with sustained high productivity (e.g., 2.75 young fledged /active nes.