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Cerca de la extinción de un pez grande y ampliamente distribuido
1J. M. Casey, Department of Biology, Memorial University of Newfoundland, St. John's, Newfoundland, Canada A1C 5S7. R. A. Myers, Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada B3H 4J1.
Science (New York, N.Y.)
|July 31, 1998
Resumen
Las extinciones de vertebrados marinos pueden estar subestimadas. Las encuestas a largo plazo muestran que el patín barndoor (Raja laevis) está a punto de extinguirse en el noroeste del Atlántico, con cero capturas en las últimas décadas.
Área de la Ciencia:
- Biología Marina Biología Marina.
- Pesca Ciencia Pesca Ciencia
- Biología de la Conservación Biología de la Conservación.
Sus antecedentes:
- Las extinciones de vertebrados marinos a menudo se consideran raras.
- Los datos sobre las tendencias poblacionales a largo plazo para muchas especies son limitados.
- Los patines son peces cartilaginosos que se enfrentan a varias presiones antropogénicas.
Objetivo del estudio:
- Evaluar el riesgo de extinción del patín barndoor (Raja laevis) en el Atlántico noroeste.
- Evaluar la exactitud de los datos actuales de la tasa de extinción de los vertebrados marinos.
- Para documentar los cambios de población a largo plazo de una especie clave de patinaje.
Principales métodos:
- Análisis de los datos de las encuestas de investigación a largo plazo independientes de la pesca.
- Comparación de las tasas de captura durante varias décadas (45 años).
- Evaluación de la distribución y abundancia de las especies en toda su área de distribución.
Principales resultados:
- El patín barndoor (Raja laevis) ha experimentado una drástica disminución de su población.
- Una vez comunes (el 10% de los remolques hace 45 años), los patines barndoor no han sido capturados en encuestas recientes (los últimos 20 años).
- Se observan disminuciones similares en todo el rango de la especie.
Conclusiones:
- El patín barndoor (Raja laevis) está en peligro crítico y cerca de la extinción.
- Los datos actuales pueden subestimar significativamente las tasas de extinción de los vertebrados marinos.
- Se necesitan medidas urgentes de conservación para esta especie y potencialmente para otras.
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