Quantifying Transboundary Plastic Pollution in Marine Protected Areas Across the Mediterranean Sea

Abstract

Micro- and macro-plastics pollution is a growing threat for marine biodiversity, ecosystem functioning, and consequently human wellbeing. Numerical models that consider main sources of plastics and simulate their dispersal characteristics are unique tools for exploring plastic pollution in marine protected areas (MPAs). Here, we used a Lagrangian plastic drift model, taking into account various sizes/types of plastic litter, originating from major land-based sources (coastal cities and rivers), to predict plastic accumulation zones in protected areas of the Mediterranean Sea (i.e., nationally designated MPAs, Natura 2000 sites, and Cetacean Critical Habitats). The model predicted that the size of plastic litters plays a key role in their dispersion and ultimate destination (i.e., larger litter travel longer distances). Most of the studied Mediterranean countries (13 out of 15) had at least one national MPA with over 55% of macroplastics originating from sources beyond their borders. Consequently, in many cases, local efforts to reduce plastic pollution in protected areas would be insufficient, especially for macroplastics management. Transboundary collaboration among Mediterranean countries is critical for implementing successful management plans against plastic pollution in their territorial waters and specifically in MPAs.

Sea surface surveys for microplastic and floating marine macro litter items in coastal waters of Cabrera Archipelago Maritime Terrestrial National Park

“…In the Canary Islands located in the Atlantic Ocean, microplastic items were observed on all of the 125 beaches surveyed, and in some beaches, these abundances were extremely high (Baztan et al 2014 ), while in a MPA in India, although abundances were lower than in non-MPA areas, plastic was continuously the most common observed item (Baroth et al 2022 ). Additionally, a more recent model highlights the connectivity between MPAs with larger plastic items travelling longer distances than smaller microplastics (Hatzonikolakis et al 2022 ). Overall, the results of this study and previous studies highlight that plastic debris is pervasive and accumulating in marine protected areas around the world.…”

Towards a strategy for the recovering of the Mediterranean monk seal in the Adriatic-Ionian Basin

“…seems to be less affected by pollutants as oil spills, heavy metals and plastics/microplastics (Vlachogianni et al, 2017;Carpenter and Kostianoy, 2018;Molina Jack et al, 2020;Hatzonikolakis et al, 2022).…”

Monitoring microplastics in coastal waters of a biosphere reserve: a case study in Menorca (Spain)

“…In this sense, there is scientific evidence that microplastic abundances deposited in sediments are higher in MPAs than in areas exposed to human pressures (Alomar et al 2016 ; Cohen-Sánchez et al 2022 ), and its distribution can also be affected by the characteristics of the seafloor (Rios-Fuster et al 2023 ). Due to currents and hydrodynamics, plastics can be transported across seas and oceans and transboundary pollution in MPAs is a reality (Compa et al 2020 ; Hatzonikolakis et al 2022 ). In this sense, there is scientific evidence that in the Mediterranean basin, all countries have at least one national MPA with over 55% of macroplastics originating from sources beyond their borders and predicted concentrations of microplastics and macroplastics are high in national MPAs and Natura 2000 sites (Hatzonikolakis et al 2022 ).…”

“…Due to currents and hydrodynamics, plastics can be transported across seas and oceans and transboundary pollution in MPAs is a reality (Compa et al 2020 ; Hatzonikolakis et al 2022 ). In this sense, there is scientific evidence that in the Mediterranean basin, all countries have at least one national MPA with over 55% of macroplastics originating from sources beyond their borders and predicted concentrations of microplastics and macroplastics are high in national MPAs and Natura 2000 sites (Hatzonikolakis et al 2022 ).…”