Estimates of abundance and longevity of Bridled Quail-Doves (Geotrygon mystacea) on Guana Island, British Virgin Islands

Clint W. Boal

doi:10.1676/1559-4491.130.4.981

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Estimates of abundance and longevity of Bridled Quail-Doves (Geotrygon mystacea) on Guana Island, British Virgin Islands

Clint W. Boal

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Abstract

The Bridled Quail-Dove (Geotrygon mystacea) is a columbiform resident of the eastern Caribbean. It is a poorly studied species with a lack of quantitative data to assess population status, but perceived population declines have led to it being considered a species of conservation concern on many islands. I attempted to assess population size and survival of Bridled Quail-Doves on Guana Island, British Virgin Islands. Based on detection probability, density estimates for Guana Island ranged from 1.38 to 1.57 individuals/ha in 2014 and 2015, respectively. Densities varied among cover type, with an estimated 1.13 individuals/ha in dry forest (90% of the island) and 4.63 individuals/ha in ghaut forest (5% of the island). These values would translate to a pooled estimate of ∼429 individuals during the survey period. Of 36 Bridled Quail-Doves captured and marked, the naïve estimate of annual survival was 0.813, with 0.36 captured individuals surviving at least 1 year, and the average minimum age at last recapture was 4.9 years old. This report is the first quantitative based estimates of population size and longevity for the species and may serve as a starting point for longer-term studies on Guana Island, but also for comparison to populations on other islands.

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Source-reported bounding extent: 18.461617616110175° to 18.49222636014645° latitude; -64.59094047546385° to -64.55437660217285° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Clint W. Boal. 2018. Estimates of abundance and longevity of Bridled Quail-Doves (Geotrygon mystacea) on Guana Island, British Virgin Islands. https://doi.org/10.1676/1559-4491.130.4.981

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