Peces endémicos de sistemas fluviales de la Selva Atlántica en la Argentina : áreas prioritarias para su conservación

Abstract

Los ecosistemas de agua dulce están entre los más amenazados por las actividades humanas y el cambio climático, por lo cual es prioritario conservarlos. La provincia de Misiones, Argentina, tiene la tasa de endemismo más alta de todas las regiones ícticas de la Argentina. El objetivo de este trabajo fue establecer el estado y la prioridades de conservación de los cursos fluviales interiores de la Selva Atlántica en la Argentina en función de la presencia de peces de distribución endémica en Misiones, evaluando su representatividad en el sistema de áreas protegidas y determinando vacíos de conservación. Se analizó la integridad ecológica de los sistemas fluviales según el grado de modificaciones, calculado mediante el índice rápido para la evaluación de calidad de ecosistemas de ribera (QBR). Se estableció su grado de protección mediante el porcentaje del curso fluvial fuera, marginal o dentro de las áreas protegidas. Se priorizaron los arroyos que eficientemente incluyeron a todas las especies endémicas. Treinta y seis cursos de agua albergan 79 especies de peces endémicos, de los cuales 22 arroyos resultan prioritarios para su conservación porque podrían proteger a todos los peces endémicos. Sin embargo, más de la mitad de estos arroyos no poseen protección y sufren alteraciones como destrucción de la vegetación marginal, represamientos, polución e introducción de especies exóticas. La mayor prioridad de conservación la tienen los cursos de agua Iguazú, Yabotí y Urugua-í, con sus afluentes.

Freshwater ecosystems are among the most threatened by human activities and climate change; so, their conservation is a priority. The province of Misiones has the highest rate of fish endemisms of all the ictic areas of Argentina. Our objective was to establish the status and conservation priorities of the interior river courses of the Atlantic Forest in Argentina in relation to the presence of endemic and distribution-restricted fish in Misiones, evaluating their representativeness in the system of protected areas and determining gaps in conservation. The ecological integrity of the river systems was analyzed according to the degree of modifications calculated by means of the rapid index for the evaluation of the quality of riverside ecosystems (QBR). Their degree of protection was estimated by the percentage of the river course outside, inside or marginal to protected areas. Streams that efficiently include all endemic species were prioritized. Thirty-six watercourses are home to 79 endemic fish species; 22 streams appear a priority for conservation because they would protect all endemic species. However, more than half of these streams are not currently protected and suffer alterations such as destruction of marginal vegetation, dams, pollution and introduction of exotic species. The highest priority for conservation was assigned to the Iguazú, Yabotí and Urugua-í watercourses with their tributaries.

Freshwater ecosystems are among the most threatened by human activities and climate change; so, their conservation is a priority. The province of Misiones has the highest rate of fish endemisms of all the ictic areas of Argentina. Our objective was to establish the status and conservation priorities of the interior river courses of the Atlantic Forest in Argentina in relation to the presence of endemic and distribution-restricted fish in Misiones, evaluating their representativeness in the system of protected areas and determining gaps in conservation. The ecological integrity of the river systems was analyzed according to the degree of modifications calculated by means of the rapid index for the evaluation of the quality of riverside ecosystems (QBR). Their degree of protection was estimated by the percentage of the river course outside, inside or marginal to protected areas. Streams that efficiently include all endemic species were prioritized. Thirty-six watercourses are home to 79 endemic fish species; 22 streams appear a priority for conservation because they would protect all endemic species. However, more than half of these streams are not currently protected and suffer alterations such as destruction of marginal vegetation, dams, pollution and introduction of exotic species. The highest priority for conservation was assigned to the Iguazú, Yabotí and Urugua-í watercourses with their tributaries.