Abundancia poblacional y manejo del jabalí (Sus scrofa): una revisión global para abordar su gestión en Argentina

,

El jabalí (Sus scrofa) es una de las especies invasoras más dañinas y cuyo manejo es prioritario a nivel mundial. Sin embargo, en la Argentina la información demográfica y las experiencias de manejo son casi nulas. En este trabajo se realiza una revisión sobre las densidades y resultados de manejo del jabalí en distintos biomas y ambientes del mundo con el objeto de alertar sobre el potencial demográfico que podría alcanzar el jabalí en cada ecorregión de Argentina y plantear las opciones de manejo más adecuadas y pertinentes en cada caso. Se revisaron 162 publicaciones sobre demografía del jabalí y 30 sobre manejo, tanto en condición nativa como exótica, dentro o fuera de áreas protegidas y en islas o en continente. El valor promedio de densidad del jabalí obtenido de la revisión bibliográfica fue de 7 (rango 0.01–115; N = 273 registros) ind/km². La mayoría (55%) de los registros se encuentran en el rango 0–3 ind/km² mientras que el 33 y 12% restantes están en los rangos 4–13 ind/km² y más de 13 ind/km², respectivamente. La especie pareciera ser más abundante en biomas tropicales y subtropicales (selvas, bosques y sabanas), en su condición exótica más que como nativa, y en islas más que en continente y dentro de áreas protegidas. La erradicación es factible únicamente en poblaciones aisladas (islas) o en aquellas recientemente instaladas, pero requiere de esquemas de control que remuevan anualmente más del 90% de los individuos. Esquemas de control basados en la combinación de métodos que remuevan anualmente el 60–70% de los individuos, resultaron eficaces. Basándose en el análisis de las densidades y de los factores de regulación del jabalí, se discute el escenario demográfico que podría alcanzarse en cada ecorregión de la Argentina y sus posibilidades de manejo para minimizar los graves impactos ambientales y socioeconómicos potenciales.


Population density and management of wild boar (Sus scrofa): a global review to address its management in Argentina. Wild boar (Sus scrofa) is one of the most harmful non-native species whose management is a worlwide priority. However, in Argentina demographic and management experience is practically absent. In this work we reviewed population densities and management results for wild boar in different biomes and habitats at world scale in order to alert about the demographic potential of this species in the Argentine eco-regions and to propose effective management options in each case. We reviewed 162 publications about wild boar populations and 30 about management where the species was native or exotic, inside or outside protected areas, or at islands or in mainland. The mean value of wild boar density obtained from our review was 7 (range 0.01–115; N = 273 records) ind/km². Most density records (55%) were within 0–3 ind/km² range, while 33 and 12% fell within 4–13  ind/km² and more than 13 ind/km² ranges, respectively. Wild boar is apparently more abundant in tropical and subtropical (rainforest, forest and savannas) biomes, more as an exotic species than as native, more on islands than in mainland, and more within protected areas. The eradication is possible if effective control methods are applied at isolated populations (within islands) or at those recently established, and removes annually 90% or more of the total individuals. Population control is possible if a combination of effective methods removes annually 60–70% of the individuals. Based on the analysis of published densities records and population regulation factors for wild boar, we discuss the potential demographic scenarios for each of the eco-regions in Argentina and the management options to minimize the expected environmental and socioeconomic impacts for the future.

Expansión poblacional de una especie introducida en la Argentina: la ardilla de vientre rojo Callosciurus erythraeus

, ,

Population expansion of an exotic mammal in Argentina: the Red-Bellied Squirrel Callosciurus erythraeus. Biological invasions are one of the major threats to biodiversity and ecosystem functioning, and they provoke economic losses to productive systems. A wild population of the Red-Bellied Squirrel Callosciurus erythraeus, native to South-east Asia, has established in the Province of Buenos Aires (Argentina) since 1973. The objective of this study is to assess the spatial distribution of the Red-Bellied Squirrel and describe the opinion of local inhabitants regarding the presence of this exotic species. We conducted 312 interviews in the district of Luján (original release site of this species) and other neighbouring districts, between August 2003 and March 2004. The area of the range distribution of squirrels was calculated using the minimum convex polygon method in a geographical information system. The present distribution of the Red-Bellied Squirrels (the only squirrel species present in this region) covers an area of approximately 680 km2. The increment of the radial distribution of squirrels was larger during the last five years (1999–2004: 1.6 km/year) than in a previous period (1973–1999: 0.3 km/year). While some inhabitants and local producers reported that the squirrels caused economic damages (e.g. in fruit plantations, afforestations, electric and irrigation systems), other inhabitants enjoy the presence of this species given its ornamental value, as a pet and even as a tourist attraction. The latter may encourage the transport of squirrels creating new invasive points, as has already occurred in the province of Córdoba (Argentina), and generating one of the major difficulties to prevent further expansion of this species.