Aliens in the Aegean – a sea under siege (ALAS)

Stelios Katsanevakis,Nikoletta Koukourouvli,Vasilis Gerovasileiou,Maria Sini,Konstantinos Tsirintanis

doi:10.3897/rio.6.e53057

Abstract

ALAS aims to fill knowledge gaps on the impacts of marine alien species in the Aegean Sea, and support marine managers and policy makers in prioritizing mitigation actions. The project will focus on under-studied alien-native interactions, priority and vulnerable habitats (such as shallow forests of canopy algae and underwater caves), and apply a multitude of approaches. It will apply a standardized, quantitative method for mapping Cumulative IMpacts of invasive Alien species on marine ecosystems (CIMPAL), according to which cumulative impact scores are estimated on the basis of the distributions of invasive species and ecosystems, and both the reported magnitude of ecological impacts and the strength of such evidence. Towards that direction, ALAS will improve our knowledge base and compile the needed information to estimate CIMPAL by (1) conducting a series of field experiments and surveys to investigate the impacts of selected invasive alien species on marine habitats, (2) producing high-resolution habitat maps in the coastal zone, refining the results of previous research efforts through fieldwork, remote sensing and satellite imaging, (3) producing species distribution models for all invasive species, based on extensive underwater surveys for the collection of new data and integrating all existing information. ALAS will incorporate skills and analyses in novel ways and provide high-resolution results at a large scale; couple classic and novel tools and follow a trans-disciplinary approach, combining knowledge from the fields of invasion biology, conservation biology, biogeography, fisheries science, marine ecology, remote sensing, statistical modelling; conduct for the first time in the Aegean Sea a comprehensive, high-resolution analysis of cumulative impacts of invasive alien species; and report results in formats appropriate for decision-makers and society, thus transferring research-based knowledge to inform and influence policy decisions.

Highlights

Scientific methodologyTo apply the CIMPAL approach, the study area (Aegean Sea) will be divided into equalarea cells
A recent global systematic review (Tsirintanis et al, unp. data) on the experimental methods applied in the terrestrial and aquatic realms for the assessment of impacts of alien species revealed that 20% of the 450 reviewed articles were conducted in the marine environment, among which 13% in the Mediterranean Sea
To estimate Ai, species distribution models will be developed for all invasive alien species

Summary

Scientific methodology

To apply the CIMPAL approach, the study area (Aegean Sea) will be divided into equalarea cells. ALAS will fill many knowledge gaps on the impacts of MIAS and the spatial extent and variation of such impacts and will contribute in improving our understanding of the mechanisms of impacts of MIAS on marine ecosystems It will provide data and results at a large-scale and high resolution, substantially enhancing our perspective of the impacts of alien species in the Aegean Sea. The cost of marine biological invasions to the economy and human health is huge through a variety of impacts, e.g. causing the decline of commercial fish stocks, the degradation of water quality through harmful algal blooms and the release of toxins, the increase of coastal erosion through the degradation of important habitats for coastal protection, the decline of the recreational value of beaches and coastal areas due to jellyfish blooms, injuries, and degradation of habitats (Katsanevakis et al 2014b).

Objectives

Findings

Funding program