Comparative study of the avifauna of three Mediterranean wetlands: Two urban wetlands (Oued Martil and Oued El Maleh, Tangier-Tetouan, northern Morocco) and Merja Zerga (ramsar site) and the impact of urbanization on these ecological niches

Abstract

The Mediterranean basin is a global hotspot for biodiversity, and wetlands are particularly recognized for their role in this hotspot. Moroccan wetlands, which are part of the broader Mediterranean system, provide habitats for endemic, threatened, and migratory species. Despite their recognized importance and the protection of several Moroccan wetlands, natural wetlands continue to be converted into agricultural lands and urban areas.They are facing anthropogenic pressures and losses in area and quality. Although these transformations have occurred, wetlands located in or near urban areas still harbor remarkable avian biodiversity. In this study, we compared the ornithological composition of urban Mediterranean wetlands, Oued Martil and Oued El Maleh (Tetouan, Northern Morocco), with the Ramsar site Merja Zerga, a classified and a protected wetland. The results show that the urban wetlands and the Ramsar site have in common 66% of families and 43% of species, including several species with significant conservation statuses. In the same way, waterbird species richness was comparable across unprotected and protected coastal wetlands. Likewise, urban wetlands of Oued Martil and Oued El Maleh, as well as the Ramsar site, support the same remarkable, heritage and IUCN- listed species. On the other hand, avian species richness was lower in urban wetlands of the Oued Martil and Oued El Maleh compared to the Ramsar site. In particular, fewer passerine were recorded, and the number of wader species was approximately two times lower in urban wetlands. These results suggest that urban wetlands can support rich and diverse bird populations and need to be protected and integrated into conservation efforts. However, they may also reflect signs of habitat degradation or reduced availability of key resources for bird species. More studies on phenology and long-term monitoring are essential to better understand the ecological significance of urban wetlands in Morocco and across the Mediterranean region.