INVESTIGADORES
BORTOLUS alejandro
congresos y reuniones científicas
Título:
Recent invaders in the South Western Atlantic: what causes underlie their invasive success?
Autor/es:
BATTINI, NICOLÁS; GIACHETTI, CLARA BELEN; KAREN CASTRO; BORTOLUS ALEJANDRO; EVANGELINA SCHWINDT
Reunión:
Congreso; International Conference on Marine Bioinvasions X; 2018
Resumen:
Alien species are among the most important threats to biodiversity, regional economies and public health worldwide. However, only a few produce conspicuous impacts and not all succeed in the same way. For long, invasion biology has inquired on the species traits and ecological processes that lead to invasion success and several hypothesis have been derived. The Enemy Release Hypothesis (ERH) argues that a species succeeds when is freed of predators and parasites in the novel environment, while the Novel Weapons Hypothesis (NWH) states that some invaders may pose novel biochemical ?weapons?, for which native predators have no adaptive defense. This work aims to unravel the reasons behind the invasion success of a recently introduced species in the SWA, and to test ERH and NWH as possible mechanisms to explain it. The opisthobranch Pleurobranchaea maculata has undoubtedly succeeded in the SWA: it has spread at a rate of 330 km per year since its first detection in 2009. This species is capable of accumulating tetrodotoxin, a potent neurotoxin previously undetected in the SWA. We focused on the predator-prey interactions to 1) identify the potential predators and their effects on P. maculata in the Nuevo Gulf and 2) examine the possible mechanisms underlying these interactions. Based on field observations and aquarium experiments, we found that none of the crabs and fishes that we identified a priori as potential predators preyed upon P. maculata, suggesting ERH, but not NWH, as a possible explanation for its success. We experimentally tested if the cryptic appearance of P. maculata or an active predator avoidance could explain the lack of predation, but we did not find evidences supporting either mechanism. We discuss alternative hypothesis that might explain the invasive success in the SWA