Anthropogenic Modifications to Estuaries Facilitate the Invasion of Non-Native Species

Enrique González-Ortegón,Javier Moreno-Andrés

doi:10.3390/pr9050740

Enrique González-Ortegón, Javier Moreno-Andrés

Open Access

https://doi.org/10.3390/pr9050740

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Abstract

New observations of non-indigenous species (NIS) in coastal waters, such as the Gulf of Cadiz (Spain) have increased since 1980 and more or less exponentially in the last five years. Ballast water has become the most significant pathway for unintentional introductions of NIS into marine ecosystems. For example, the marine larvae of crustacean decapods that inhabit the water column could be transported in ballast water. Although elevated concentrations of metals are toxic to many marine organisms, some of them have evolved effective detoxification, or avoidance mechanisms making it possible to consider they have a superior ability to withstand exposures to these toxicants. In this text, we try to reinforce the hypothesis that anthropogenic modifications (such as chemical alterations and modified environments) benefit NIS with broad environmental tolerances. Taking these risks into account, a reinforcement of efficient Ballast Water Management Systems to respond to today’s challenging environmental conditions is discussed.

Highlights

An Increase in the Arrival of SpeciesNew worldwide observations of non-native invasive species (NIS) have increased over time, for instance in the Gulf of Cadiz (Spain), GoC, since 1980 and even more in the last five years [1]
The continued transport of planktonic species such as decapod crustacean larvae in ballast water would ensure the arrival of this group of species in plankton, which might explain the success of this group of species in coastal waters
Ballast water is an important vector for the dispersal of pre-adult stages and other microorganisms from different geographical areas that are not naturally connected

Summary

Introduction

New worldwide observations of non-native invasive species (NIS) have increased over time, for instance in the Gulf of Cadiz (Spain), GoC, since 1980 and even more in the last five years [1]. Darling et al 2020 found considerably higher ratios of arthropods (mainly copepods) or mollusks in ballast tanks [15] In this way, the transport of larvae over long distances via ballast water could assure the transport of planktonic species or those species with a planktonic phase, the success of their future establishment depends on biotic and abiotic factors upon arrival in the ecosystem. The transport of larvae over long distances via ballast water could assure the transport of planktonic species or those species with a planktonic phase, the success of their future establishment depends on biotic and abiotic factors upon arrival in the ecosystem This text focuses on how anthropogenic modifications influence the establishment of plankton (zooplankton (≥50 μm) or phytoplankton species (10–50 μm)) and microorganisms at a location outside their native range The Port of Algeciras, one of the biggest ports in Europe, is present in this area

The Suitability of an Estuarine Environment to Host Non-Native Species

Pollution-Tolerant Species

Modifications to the Coastal Habitat

Climate-Related Invasion of Non-Native Species

Conclusions