Climate change is causing an increase in the frequency and intensity of marine heatwaves (MHWs) and mass mortality events (MMEs) of marine organisms are one of their main ecological impacts. Here, we show that during the 2015–2019 period, the Mediterranean Sea has experienced exceptional thermal conditions resulting in the onset of five consecutive years of widespread MMEs across the basin. These MMEs affected thousands of kilometers of coastline from the surface to 45 m, across a range of marine habitats and taxa (50 taxa across 8 phyla). Significant relationships were found between the incidence of MMEs and the heat exposure associated with MHWs observed both at the surface and across depths. Our findings reveal that the Mediterranean Sea is experiencing an acceleration of the ecological impacts of MHWs which poses an unprecedented threat to its ecosystems' health and functioning. Overall, we show that increasing the resolution of empirical observation is critical to enhancing our ability to more effectively understand and manage the consequences of climate change.

The European Regulation (EU) 1143/2014 on Invasive Alien Species entered into force in 2015, with the aim to fulfill regional and international biodiversity goals in a concerted manner. To date, the Regulation listed 66 Invasive Alien Species (IAS) that are subject to legal controls. Only one of these is marine. A recent lionfish (Pterois miles) invasion has been closely monitored in the Mediterranean and a detailed risk assessment was made about the profound impacts that this invasive fish is likely to have on the fisheries and biodiversity of the region. In 2016–21, lionfish rapidly became dominant predators along Eastern Mediterranean coasts, yet the process for their inclusion on the EU IAS list has been lengthy and is ongoing. There is an urgent need to learn from this experience. Here, we recommend improvements to the Regulation 1143/2014 and the risk assessment process to protect marine ecosystems and secure the jobs of people that rely on coastal resources.

Fisheries are among the sectors hardest-hit by the coronavirus pandemic (COVID-19) crisis due to the sudden decrease in the demand for seafood. This study employs demand-driven and supply-driven input-output models to conduct an economy-wide assessment of the contraction of the fisheries activities in Cyprus, as well as a questionnaire survey to reveal fishermen’s perceptions of COVID-19 crisis impacts. The results at the macroeconomic level reveal that the contraction in the economic output of the fisheries sector does not have any significant impact on the wider economy due to the small size of the sector. However, the COVID-19 crisis has major negative effects on fishermen’s income and the livelihoods of fishers’ households. The average gross margin of the interviewed fishermen for March 2020, i.e., the month where a national quarantine and lockdown was imposed, was four times less the average monthly gross margin for the winter period (December 2019–February 2020) and 2.5 times less compared to the average monthly gross margin of 2019. The recessionary impacts of the COVID-19 crisis in conjunction with the chronic challenges that fisheries are currently facing in Cyprus, negatively affect the viability of the sector.

The Mediterranean bryozoan fauna is considered to be well studied compared to other marine areas of the world. However, in the Levantine Basin, bryozoan diversity has not yet been adequately documented. This report presents the first systematic and most comprehensive study of bryozoans sampled in Cyprus during census surveys from 2011 to 2018. The specimens were collected between 9 and ~620 m depth from several habitat types (mainly soft-bottom environments but also hard natural/artificial substrata, ancient shipwrecks, a marine cave, and deep-water coral habitats) around the island by means of bottom trawls, remotely operated vehicles, and scuba diving. The surveys produced a total of 91 species, 26 of which (=28%) are new records for the Levantine Basin, and 10 (=11%) are probably new to science. Our results thus show that the diversity of bryozoans in the eastern Mediterranean Sea is still significantly underestimated.