Determinación del éxito reproductivo del alcatraz enmascarado (Sula dactylatra dactylatra, Pelecaniformes:Sulidae) en Cayo Middle, Banco de Pedro Jamaica

Pete Ainsworth,Dale F St G Webber

doi:10.15517/rbt.v62i0.15911

Abstract

Received 17-X-2013 Corrected 13-III-2014 Accepted 24-III-2014 Abstract: The masked booby (Sula dactylatra dactylatra) colony at Middle Cay, Pedro Bank, 60 miles south of Jamaica, has been affected by challenges resulting from anthropogenic disturbances. Despite habitat degrada- tion, the colony displays resilience by remaining extant on the cay. Between June 2008 and June 2009 we inves- tigated the colony's health (mainly breeding success). Data were collected once per month for twelve months and included one day, seven day and 24 hour (day and night continuous observational) sojourns. Forty-four nests were marked and monitored using a novel method for marking seabird nests based on painted seashells. Data collected from the colony included: the presence/absence/number of egg(s)/chick(s) in nests, offspring maturity, adult attendance at nests and the time of data collection. An average of 227 adult birds constituted the colony. Using the Mayfield Method and the Naive Estimator for comparison, the colony's breeding success was determined to be 37.20% despite a hatching success of 40% and a fledgling success of 93%. This is less than the estimated 45.77% success typical of healthy colonies of sulids such as the masked booby elsewhere. Based on the breeding success calculations the long term survival of this colony is at risk and needs active conservation. Rev. Biol. Trop. 62 (Suppl. 3): 159-167. Epub 2014 September 01.

Highlights

The Caribbean with its tropical environment provides a variety of unique habitats for avian species which survive with other organisms within undisturbed ecosystems
One such avian species within Jamaica for which limited information is available is the seabird Sula dactylatra dactylatra (Lesson, 1931); the masked booby (Atlantic). This seabird species is extant in separate colonies on two of three inhabitable cays located at Pedro Bank Jamaica
By serving as a habitat for more than five seabird species, Pedro Bank’s Cays (Pedro Cays) are of importance to Jamaica’s seabird diversity and to Neotropical migrants that stopover to rest during their yearly southward journey

Summary

Introduction

The Caribbean with its tropical environment provides a variety of unique habitats for avian species which survive with other organisms within undisturbed ecosystems. This may be so since Caribbean ornithology is often focused on birds with direct economic importance, eye-catching appearances or those that exist within habitats which are conveniently accessible One such avian species within Jamaica for which limited information is available is the seabird Sula dactylatra dactylatra (Lesson, 1931); the masked booby (Atlantic). The Bank’s submerged environment provides good habitat for a variety of organisms and represents one of Jamaica’s last remaining healthy marine ecosystems, supporting coral reefs, sea grass beds and coral cays (Levy & Koenig, 2009). This healthy marine ecosystem makes Pedro Bank an ideal. This study was designed to provide information on the Middle Cay masked booby colony’s health or resilience within its disturbed habitat through the determination of its breeding success and comparisons between the colony’s observed success and that of healthy colonies in relatively undisturbed habitats

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Conclusion