|Author(s):||R. Tiberti, T. Buchaca, D. Boiano, R. A. Knapp, G. Tavecchia, M. Ventura, S. Tenan|
|Title:||Alien fish eradication from high mountain lakes by multiple removal methods: estimating residual abundance and eradication probability in open populations|
|Journal:||JOURNAL OF APPLIED ECOLOGY|
- Invasive alien species are among the most important threats to
biodiversity. Plans for their eradication have been implemented
worldwide but estimating residual population size and eradication
probability to assess removal success is complicated by the imperfect
detection of residual individuals.
- Most methods to assess residual abundance and
eradication probability rely on the often unrealistic assumption that a
population is closed to mortality and recruitment processes during the
implementation of removal actions. We extended existing removal models
and developed a novel analytical approach to estimate residual
population size and derive eradication probability in open populations
while accounting for multiple removal methods.
- We apply this approach to 20 eradication projects in
Europe and the United States that used mechanical methods to return high
mountain lakes to their original fishless condition.
- The new removal model incorporates (a) a mechanistic
description of the ecological process underlying survival and
recruitment probabilities during the eradication period and (b) the use
of multiple, concomitant removal methods (i.e. electrofishing,
gillnetting, fyke‐netting) at multiple sites simultaneously.
- We used a subset of ‘control’ lakes where eradication
success was confirmed by more than 5 years of post‐removal surveys to
validate the model. For these lakes, eradication success, evaluated by
whether the 95% Bayesian credible interval for estimated residual
population size encompassed values of <2 individuals, was confirmed
in 13 out of 15 lake‐by‐species case studies. In addition, the model
correctly assigned an eradication probabilities equal to 0 for the
eradications that are still in progress.
- Synthesis and applications. Our study provides
insights into the dynamics of fish populations subject to eradication in
high mountain lakes of different countries. In addition, the analytical
approach proposed accounts for demographic processes and multiple
removal methods in multiple sites and seasons. It can represent an
informative tool to estimate residual population size and eradication
probability of alien species to optimize eradication efforts and
efficacy of conservation actions. The extension to open populations
makes the approach useful to evaluate long‐term eradication plans.
Related staffGiacomo Tavecchia
Related departmentsAnimal and Microbial Biodiversity
Related projectsPERSIL (CTA 162)
Related research groupsEcology and Evolution