Insights on the origin of invasive copepods colonizing Basque estuaries; a DNA barcoding approach

A Albaina,A Iriarte,I Uriarte,D Abad,A Estonba,M Aguirre,F Villate

doi:10.1186/s41200-016-0045-2

Abstract

The introduction of NIS to estuaries and coastal embayment is of great concern. Commercial ships’ ballast water discharge and the northwards progression of species due to the ongoing climate change arise as the main factors explaining the rising occurrence of NIS species in Northern Atlantic waters. In this regard, regular monitoring of the plankton communities is paramount as to be able to respond properly to this potential issue. While monitoring the invasive copepod Acartia tonsa populations in the estuaries of Bilbao and Urdaibai (Basque country, Spain), we report here the Asian copepod Pseudodiaptomus marinus for the first time in the Iberian Peninsula waters. Individuals from both species were collected from July to October, 2013 for DNA sequencing of mitochondrial cytochrome c oxidase subunit I gene (MT-CO1). Phylogenetic analysis of MT-CO1 confirmed P. marinus identity. Phylogeographic distribution of A. tonsa haplotypes in Europe along with the Bilbao port traffic patterns suggested a secondary invasion from an European source to Basque estuaries. The successful establishment of the A. tonsa population and the appearance of Pseudodiaptomus marinus confirm the need for regular plankton monitoring of estuarine and port waters. This applies also to nearby systems as these populations could represent a source of future dispersal.

Highlights

The introduction of Non Indigenous Species (NIS) to estuaries and coastal embayment is of great concern
The introduction of NIS to estuaries and coastal embayment is of great concern and regular monitoring of these sensitive ecosystems for NIS and its ecological impact is paramount for a timely answer and any further mitigation/adaptation policy design
While up to four Acartia species were recorded in the estuary of Urdaibai in summer 2013, A. tonsa was the sole representative in the estuary of Bilbao

Summary

Introduction

Commercial ships’ ballast water discharge and the northwards progression of species due to the ongoing climate change arise as the main factors explaining the rising occurrence of NIS species in Northern Atlantic waters. In this regard, regular monitoring of the plankton communities is paramount as to be able to respond properly to this potential issue. The introduction of NIS to estuaries and coastal embayment is of great concern and regular monitoring of these sensitive ecosystems for NIS and its ecological impact is paramount for a timely answer and any further mitigation/adaptation policy design. Our objectives were to 1) examine the genetic information of the known NIS A. tonsa in both estuaries and gain insights into the invasion source by comparing mitochondrial DNA (mtDNA) sequences obtained from the native and introduced ranges (e.g. Downie 2002; Cristescu 2015 for a review) and 2) discover any novel invasive species to these Basque estuaries

Objectives

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Results

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Conclusion