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dc.contributor.advisorBird-Picó, Fernando J.
dc.contributor.authorRoss, Gail S.
dc.date.accessioned2018-05-16T16:12:08Z
dc.date.available2018-05-16T16:12:08Z
dc.date.issued2007
dc.identifier.urihttps://hdl.handle.net/20.500.11801/573
dc.description.abstractThe apparent decline in amphibian populations worldwide has driven the need to establish more effective monitoring strategies. Puerto Rico has experienced the loss of three species of amphibians, and a decline in six others including the island’s only endemic toad, the Puerto Rican crested toad (Bufo lemur). Puerto Rican crested toads were once distributed along the northern and southern karst belt of the island but the last known northern individuals were observed in 1992. In this study a survey was carried out in the north of Puerto Rico over the course of a year with an aim to survey amphibians at four documented Puerto Rican crested toad breeding ponds and at a potential captive bred toad release site, compare habitat characteristics, land-use changes, the presence of other pond-dwelling organisms, and develop recommendations on future search protocols and captive bred toad reintroductions. Six species of amphibians, including two exotics (Bufo marinus and Osteopilus septentrionalis) were detected over the 2006 survey period. Puerto Rican crested toads were not detected. Land use change analysis indicated a 21% increase in urban development contiguous to the ponds between 1963 and 2001, but no development between the ponds and Bellaca creek. Additional land use change leading to habitat fragmentation and the presence of invasive amphibians could have played a role in stressing extant Puerto Rican crested toad populations. Without the availability of suitable habitat and protection it would seem impractical to recommend the release of captive bred individuals to the area. Continued and expanded searches may still yield extant individuals.en_US
dc.description.abstractLa disminución aparente de poblaciones de anfibios a nivel mundial motiva el establecimiento de estrategias de monitoreo más eficientes. Tres especies de anfibios han desaparecido de Puerto Rico, y se han documentado declives en otras seis especies, incluyendo al único sapo endémico de la isla, el sapo concho puertorriqueño (Bufo lemur). El sapo concho puertorriqueño se distribuyó históricamente en la zona cársica del norte y sur de la isla, aunque los últimos individuos del norte se observaron en 1992. Durante este estudio se llevó a cabo un monitoreo durante un año en cuatro charcas de reproducción y una zona de potencial de liberación al norte de Puerto Rico. Se compararon características de hábitat, cambios de uso de terreno, presencia de otros organismos acuáticos, y se desarrollaron recomendaciones para protocolos de búsqueda y liberación de renacuajos producto de reproducción en cautiverio. Seis especies de anfibios, incluyendo a dos especies exóticas (Bufo marinus y Osteopilus septentrionalis) se detectaron durante el monitoreo de 2006. No se detectó al sapo concho puertorriqueño. Análisis de cambio en uso de terreno indicaron que el desarrollo urbano aumento un 21% cerca de las charcas entre 1963 y 2001, aunque no hubo desarrollo de terreno entre las charcas y la quebrada Bellaca. El cambio en uso de terreno que fragmentó el hábitat y la presencia de especies invasoras pudieron añadir estrés a las poblaciones restantes de Bufo lemur. Sin hábitat adecuado o protección parece poco práctico recomendar la liberación de individuos de propagación en cautiverio en el área. Se podrían aún encontrar individuos por medio de búsquedas continuas y de mayor cobertura.en_US
dc.description.sponsorshipThe WALSAIP project (Department of Electrical and Computer Engineering). Juan G. González Lagoa and the Resource Center for Science and Engineering funding his travel to the SCGIS conference in California, where SCGIS and ESRI provided GIS training and ArcGIS programs. Funding was provided by cooperative agreement # 1448-40181-04J012 between US Fish and Wildlife Service and Iniciativa Herpetológica, Inc.en_US
dc.language.isoenen_US
dc.subjectAmphibian populationsen_US
dc.subjectPuerto Rican crested toad (Bufo lemur)en_US
dc.subjectPuerto Rican crested toad breeding pondsen_US
dc.subjectPotential captive bred toaden_US
dc.subjectBufo marinus and Osteopilus septentrionalisen_US
dc.subject.lcshBufo--Habitat--Puerto Rico--Quebradillasen_US
dc.subject.lcshToads--Habitat--Puerto Rico--Quebradillasen_US
dc.titleBiotic and abiotic factors affecting calling activity at traditional breeding ponds of Puerto Rican crested toads (Bufo [Peltophryne] lemur) in Quebradillas, Puerto Ricoen_US
dc.rights.licenseAll rights reserveden_US
dc.rights.holder(c) 2007 Gail S. Rossen_US
dc.contributor.committeeLewis, Allen R.
dc.contributor.committeeSantos, Carlos J.
dc.contributor.committeePuente Rolón, Alberto R.
dc.contributor.representativeCruz-Burgos, José A.
thesis.degree.levelM.S.en_US
thesis.degree.disciplineBiologyen_US
dc.type.thesisThesisen_US
dc.contributor.collegeCollege of Arts and Sciences - Sciencesen_US
dc.contributor.departmentDepartment of Biologyen_US
dc.description.graduationYear2007en_US


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