Jorge Andrés Noel Cranwell (1916-2002)

El 26 de febrero de 2002 falleció en Buenos Aires, en su casa, Jorge A. N. Cranwell. Herpetólogo, autodidacto. El "Doctor" Cranwell, como era conocido por todos, se incorpora al Museo Argentino de Ciencias Naturales "Bernardino Rivadavia" (MACN) en 1937, de la mano del mastozoólogo José Chepes, ingresando definitivamente en febrero de 1938 como personal de planta. Inicialmente, su interés se centró en los mamíferos fósiles, pero éste fue cambiando rápidamente hacia la herpetología. En su legajo, la primera referencia a funciones referidas a esta disciplina data de diciembre de 1940, aunque en la colección existe material colectado por él ya desde años anteriores. Durante años costeó gastos de la división herpetología, financió campañas, y contribuyó con los inicios de la AHA. Demostró gran interés por la conservación de la naturaleza, apoyando instituciones y atendiendo conferencias, pero en su conversación dejaba translucir un resignado escepticismo.Asociación Herpetológica Argentina (AHA

Conservation Status of the Argentine Boa Constrictor (Boa constrictor occidentalis) 20 Years After Being Listed in CITES Appendix I

Twenty years after the species was listed in CITES Appendix I, we carried out a comprehensive review of the conservation status of the Argentine Boa Constrictor (Boa constrictor occidentalis) in Argentina. We compiled background information on trade, biology, and distribution. We evaluated the historical range on the basis of museum and literature records, and later adjusted it to  incorporate environmental variables. We carried out 573 interviews with local residents regarding the historical presence of the species and the ways in which it was used. Using a rapid assessment of woody vegetation cover, we estimated the degree of habitat loss in Argentina. We conclude that CITES has been very effective in stopping the international trade and almost completely eliminating hunting pressure on this snake throughout Argentina. However, suitable boa habitat has been reduced by one third to approximately 30 million ha from a historical extent of occurrence of about 42 million ha in the Dry Chaco ecoregion. Loss of suitable habitat is mainly  due to recent expansion in agricultural and livestock production. This subspecies is still common  throughout its range; however, recent trends in habitat loss led us to conclude that the Argentine Boa Constrictor meets at least one of the CITES criteria for retention in Appendix I, at least until the recently enacted forest protection law proves its effectiveness in protecting the remaining Chaco forests of Argentina

Categorización del estado de conservación de los caimanes (yacarés) de la República Argentina

Después de transcurridos más de 10 años desde la primera Lista Roja de la herpetofauna de la República Argentina realizada por la Asociación Herpetológica Argentina en el año 2000, se re-categorizaron las dos especies de caimanes presentes en el país (Caiman latirostris y C. yacare) incorporando nueva información biológica, biogeográfica y ecológica y, correcciones metodológicas. Como resultado, ambas especies fueron categorizadas como No Amenazadas, en base a información actualizada sobre sus áreas de distribución y su abundancia. Los criterios aplicados para el desarrollo de los programas de manejo de ambas especies en Argentina han permitido ampliar el conocimiento de las mismas en una gran diversidad de aspectos. El aprovechamiento sostenible de los yacarés mediante la metodología de cría en granjas o “rancheo” ha demostrado ser de bajo impacto para las poblaciones silvestres y ha revalorizado los humedales que estos reptiles habitan.After more than a decade from the first Red List of the Herpetofauna of Argentina assessed in 2000, we reclassified the two species of argentine caimans, starting from actual information about their biology, biogeography and ecology and including methodological adjustments. As a result, both species Caiman latirostris and C. yacare were included in the Not Endangered category, based on new records about their geographic distribution and populations densities. The criteria applied to the development of management programs of crocodilians in Argentina has improved the knowledge of both species and made a great and wide contribution to several aspects of their biology. The sustainable use of both species of crocodilians has proved to have a minimum impact on wild populations and has put a new value on the wetlands inhabited by this reptiles.Asociación Herpetológica Argentin

Categorización del estado de conservación de las tortugas de la República Argentina

Con la participación de nueve especialistas de diferentes instituciones de Argentina y transcurridos más de 10 años desde la primera Lista Roja de la herpetofauna de la República Argentina realizada por la Asociación Herpetológica Argentina en el año 2000, se re-categorizaron los taxones de Testudines presentes en el país incorporando nueva información taxonómica, biológica y ecológica y, aplicando correcciones metodológicas. Como resultado, de los 14 taxones de tortugas continentales y marinas, nueve quedaron incluidas en la presente Lista Roja bajo algún grado de amenaza, tres En Peligro, tres Amenazadas y tres Vulnerables, mientras que dos fueron categorizadas como No Amenazadas y tres son Insuficientemente Conocidas. En la evaluación de las tres especies de tortugas marinas, que frecuentan las costas del Mar Argentino, se homologaron las categorías con las de IUCN (2011). Respecto de la categorización anterior, se agregó la especie Phrynops geoffranus (Insuficientemente Conocida), se sinonimizaron dos especies, disminuyó el número de especies En Peligro de tres a dos y se incrementó el de Vulnerables de una a tres. Los pocos cambios resultantes de la presente categorización de las tortugas de Argentina respecto de la anterior podría reflejar la escasez de estudios realizados sobre este grupo en la última década y la necesidad de promoverlos.Through the participation of nine specialists from different institutions from all over Argentina and after more than a decade from the first Red List of threatened herpetofauna proposed by Asociación Herpetológica Argentina in 2000, we assessed the conservation status of the argentine Testudines taxa, adding the new taxonomic, biological and ecological knowledge progresses made since then as well as applying methodological changes in the former assessment. As a result from the 14 turtles taxa recognized as present in Argentina, nine were included in the actual Red List under some degree of risk (three Critically Endangered, three Endangered, three Vulnerable). From the remaining ones, three were classified as Insufficiently Known and two as Not Threatened. In the classification of the three marine turtles that are frequently found in argentine coasts we adopted the IUCN (2011) Red List criteria. In relation with the former categorization, we included a new species registered in Argentina (Phrynops geoffranus, Insufficiently Known), added two synonymies, increased from one to three the species within the Vulnerable Category and decreased from three to two the Critically Endangered species number. The few changes between the two assessments of the argentine turtle´s conservation status are due to the scarcity of new scientific contributions made to the knowledge of this group in the last decade.Asociación Herpetológica Argentina (AHA

Population Structure and Gene Flow of the Yellow Anaconda (Eunectes notaeus) in Northern Argentina

Yellow anacondas (Eunectes notaeus) are large, semiaquatic boid snakes found in wetland systems in South America. These snakes are commercially harvested under a sustainable management plan in Argentina, so information regarding population structuring can be helpful for determination of management units. We evaluated genetic structure and migration using partial sequences from the mitochondrial control region and mitochondrial genes cyt-b and ND4 for 183 samples collected within northern Argentina. A group of landscape features and environmental variables including several treatments of temperature and precipitation were explored as potential drivers of observed genetic patterns. We found significant population structure between most putative population comparisons and bidirectional but asymmetric migration in several cases. The configuration of rivers and wetlands was found to be significantly associated with yellow anaconda population structure (IBD), and important for gene flow, although genetic distances were not significantly correlated with the environmental variables used here. More in-depth analyses of environmental data may be needed to fully understand the importance of environmental conditions on population structure and migration. These analyses indicate that our putative populations are demographically distinct and should be treated as such in Argentina's management plan for the harvesting of yellow anacondas