INVESTIGADORES
FASOLA Laura
artículos
Título:
Linking invasive exotic vertebrates and their ecosystem impacts in Tierra del Fuego to test theory and determine action
Autor/es:
VALENZUELA AEJ; ANDERSON CB; FASOLA L; CABELLO J
Revista:
ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY
Editorial:
GAUTHIER-VILLARS/EDITIONS ELSEVIER
Referencias:
Lugar: Paris; Año: 2013
ISSN:
1146-609X
Resumen:
Understanding processes and impacts of biological invasions is fundamental for ecology and management.
Recent reviews summarized the mechanisms by which invasive species alter entire ecosystems,
but quantitative assessments of these mechanisms are lacking for actual assemblages to determine their
relative importance, frequency and patterns. We updated information on introduced vertebrates in the
Tierra del Fuego Archipelago (TDF) via an exhaustive literature review and new data to evaluate ecosystem
impact mechanisms and provide management recommendations. To date, 24 exotic vertebrates
have naturalized in TDF, outnumbering natives nearly 2:1, with the North American beaver (Castor
canadensis) and muskrat (Ondatra zibethica) being the most widely distributed species and also
impacting the ecosystem through the greatest number of mechanisms. Introduced vertebrates occupied
most parts of the archipelago with human-inhabited islands having greater taxa richness. All exotics
potentially altered ecosystems by one or more mechanisms: 100% food webs, 92% invasional meltdown,
42% habitat modification, 38% disease or parasite transmission, 21% soil property and disturbance regime
changes. Impact to habitat structure was the main clustering criterion for this assemblage. Within the
species that physically alter habitats, we found two sub-groups: 1) large herbivores and 2) others
including beavers and muskrats. Species that did not alter habitat were divided further into those with
predatory trophic effects (carnivorous mammals and trout, sub-group 4) and the rest with assorted
impacts (sub-group 3). By establishing high quality information on archipelago-wide assemblage, distribution,
impacts and mechanisms for exotic vertebrates, we recommend, based on ecological criteria,
prioritizing the management of sub-group 2. A secondary priority might be given to the carnivores in
sub-group 4, while species in sub-groups 1 and 3 are less urgent. As the first systematic survey of
introduced fauna on an archipelago-scale, we identified knowledge gaps, such as population abundance
and dynamics for specific species, which are needed to orient future work, but the notable progress made
to date is highlighted.