RESUMO
Lama guanicoe se distribuyó en los Andes de Chile desde Arica y Parinacota hasta Magallanes. Actualmente su distribución está fragmentada con poblaciones en las regiones de Tarapacá, Coquimbo, Aysén y Magallanes. En el Parque Nacional Bosque Fray Jorge (Coquimbo), las últimas poblaciones de guanacos silvestres se observaron el año 1920. En 1994 se liberaron ocho individuos en el Parque de los cuales cinco sobrevivieron. Desde entonces se realizaron conteos ocasionales de la población reintroducida. En noviembre de 2013 se elaboró una metodología de monitoreo con base en transectos de conteo. Los objetivos fueron analizar los cambios históricos de la abundancia poblacional de guanacos en el Parque y determinar el uso y selección de hábitat. Se emplearon modelos lineales para analizar las tendencias poblacionales y el Cociente de Selección de Manly para la selección de hábitat. Se evidenció incremento de la población hasta 33 individuos. El principal uso que dieron a los tipos de cobertura fue la alimentación y seleccionaron el Matorral Desértico Mediterráneo Interior de Heliotropium stenophyllum y Fluorensia thurifera. Se recomienda marcar los guanacos con collares satelitales para hacer un seguimiento de los movimientos de las tropas, establecer territorios y medir el tamaño poblacional.
Lama guanicoe was distributed in the Andes of Chile from Arica and Parinacota to Magallanes. Currently its distribution is fragmented with populations in Tarapaca, Coquimbo, Aysen and Magallanes Regions. In the Bosque Fray Jorge National Park (Coquimbo), the last populations of wild guanacos were observed in the year 1920. In 1994, eight individuals were released in the Park, of which five survived. Since then, occasional counts of the reintroduced population were made. In November 2013, a monitoring methodology was developed based on count transects. The objectives were to analyze the historical changes in the population of guanacos in the Park and determine the use and selection of habitats. Linear models were used to analyze population trends and the Manly Selection Ratio for habitat selection. There was an increase in the population to 33 individuals. The main use that they gave to the types of cover was the feeding and they selected the Mediterranean Mediterranean Desert Scrub of Heliotropium stenophyllum and Fluorensia thurifera. It is recommended to mark the guanacos with satellite collars to monitor the movements of the troops, establish territories and measure the population size.
RESUMO
Large animals are important seed dispersers; however, they tend to be under a high extinction risk worldwide. There is compelling evidence that the global biodiversity crisis is leading to the deterioration of several ecosystem functions, but there is virtually no information on how large-scale refaunation efforts can reinstate seed dispersal. We evaluated the effectiveness of a 62-km2 wildlife sanctuary, which was established to recover populations of large mammals in Gorongosa National Park (Mozambique), in restoring seed dispersal. We collected animal scats during the dry season of 2014 (June-August) along 5 transects inside and 5 transects outside the sanctuary fence (50 km total) with the same type of plant community, identified animal and plant species in the transects, and quantified the number of seeds in each scat. Based on these data, we built bipartite networks and calculated network and species-level descriptor values, and we compared data collected inside and outside the sanctuary. There were more scats (268 vs. 207) and more scats containing seeds (132 vs. 94) inside than outside the sanctuary. The number of mammal dispersers was also higher inside (17) than outside the sanctuary (11). Similarly, more seeds (2413 vs. 2124) and plant species (33 vs. 26) were dispersed inside than outside the sanctuary. Overall, the seed-dispersal network was less specialized (0.38 vs. 0.44) and there was a greater overlap (0.16 vs. 0.07) inside than outside the sanctuary. Both networks were significantly modular and antinested. The high number and richness of seeds dispersed inside the sanctuary was explained mostly by a higher abundance of dispersers rather than by disperser identity. Our results suggest conservation efforts aimed at recovering populations of large mammals are helping to reestablish not only target mammal species but also their functional roles as seed dispersers in the ecosystem.
