The occurrence, distribution and biology of invasive fish species in fresh and brackish water bodies of NE Morocco

A F Taybi,I Doadrio,Y Mabrouki

doi:10.32800/amz.2020.18.0059

Abstract

Monitoring the presence and expansion of alien species and upgrading their biological and ecological knowledge seems crucial to mitigate their possible impact on native communities. Within inland superficial waters, alien fish represent an important threat to the biodiversity and studies on their impact on native communities have increased around the world in the last years. However, little is known about their occurrence, biology and influences in North Africa in general, and more specifically in Morocco. In the present work we aimed to: 1) investigate the presence of any native Aphanius species, especially the Mediterranean killifish Aphanius fasciatus recorded from the lower basin of the Moulouya River (NE Morocco); 2) monitor the presence and expansion of two invasive species, the eastern mosquitofish Gambusia holbrooki and the mummichog Fundulus heteroclitus; and 3) contribute to the understanding of the ecological and abiotic affinities that govern the distribution of these alien fishes in North Africa. To achieve these goals, several field sampling campaigns were carried out between 2014 and 2018 across eastern Morocco, comprising the administrative Oriental Region and the Moulouya River Basin and covering an area of 119,268 km2. No native Aphanius species were found. The eastern mosquitofish has invaded the freshwater hydrosystems of the northern part of Morocco, including the study area, while the mummichog is currently limited to the brackish and salty wetlands of Lower Moulouya. Our results show that the known ranges of these two alien species have expanded. Data published through GBIF (Doi:10.15470/2qed9o)

Highlights

Biological invasions are one of the most important human impacts on a wide range of ecosystems and a major cause of global change (Ricciardi, 2006)
This study aimed to evaluate the presence of A. fasciatus or any native Aphanius species in NE Morocco, in parallel with the two invasive species G. holbrooki and F. heteroclitus
Its probable range was totally occupied by two exotic fish species F. heteroclitus and G. holbrooki

Summary

Introduction

Biological invasions are one of the most important human impacts on a wide range of ecosystems and a major cause of global change (Ricciardi, 2006). Many members of the genus Aphanius are “victims” of biological invasion, such as the Mediterranean killifish, A. fasciatus (Valenciennes, 1821), a cyprinodotid fish whose native range includes coastal brackish–waters mainly in the coastal zone of the central and eastern Mediterranean (Bianco, 1995). It can be found in various inland water bodies, such as lakes, inland streams and even in some North African oases (Hrbek and Meyer, 2003; Güçlü et al, 2013). The Mediterranean killifish was reported in Morocco for the first time at the wetland of the Moulouya River mouth by Melhaoui (1994), but the species has not been reported since this record

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