Evaluating efficacy of a ballast water chlorination treatment on zooplankton community to prevent transport of non-indigenous species

BRISKI E.,; MACISAAC H,; PAOLUCCI, ESTEBAN; HERNANDEZ M. C..; ZHAN A,; LIN, Y.

Hangzhou

Conferencia; International Conference on Biological Invasions; 2017

International Conference on Biological Invasions

Human-mediated invasions by non-indigenous species (NIS) have become a global ecologicaland conservation problem. Recognizing possible relationship between population size, geneticvariation and fitness are of fundamental importance in understanding the invasion success. Strongpropagule vector, such as ships? ballast water, is an ideal system to characterize this relationship asit typically contains abundant and diverse aquatic taxa that often suffer from population attenuationduring transport due to harsh conditions. Reduced population size tends to lead to loss of geneticdiversity that is generally perceived as a significant barrier to successful establishment. Still, inmany cases, small founding populations of introduced species exhibit relatively high invasionpotential. The simplest explanation for a high invasion success of the low-diversity introductionsmay be that the loss of genetic diversity of introduced populations is non-stochastic, but it preservesadaptive genetic variation to avoid negative impact of low population size. This prediction is largelyhypothetica l, but nevertheless ecologically important if it can be demonstrated that remained genetic variation may structure better fit populations for invasions due to selection; even though those populations may be rare. Thus, the main objective of this study is to determine if neutral alleles and/or dominant alleles decline more rapidly than pre-adapted ones. Here, I will analyze dynamics of population size and pattern of population genetic diversity of zooplankton in ship ballast tanks during transoceanic voyages, as well as environmental characteristic of ballast water (e.g. temperature, salinity, pH, dissolved oxygen). Further, I will study one representative species withnon-stochastic loss of genetic diversity following the reduction of its population size, and conduct restriction-site-associated DNA sequencing (RAD-seq) analysis to confirm reduced diversity at different types of genetic loci, including neutral and non-neutral loci. Finally, by analysing theobtained results, I will determine if population attenuation during the transport stage of the invasion process may produce populations with high invasion success.