Climate change and pollution are just two of the many impacts on marine life which, in turn, affect the marine ecosystem services and functions sustaining life on this planet.

So World Oceans Day, celebrated on June 8, is important to remind society that this blue planet needs us to take care of all the blue parts of our world, even those far away from sight, apart from the green we easily see vanishing every day.

The experience of the Conservation Bio­logy Research Group, led by Adriana Vella, has seen many discoveries, such as the first scientific report of fin whales in Maltese coastal waters in 2007, as part of long-term research on dolphins and whales, turtles and many other marine species around our islands. This experience and expertise has been applied to scientific research beyond Maltese waters in other regions in the Mediterranean to aid required knowledge on these vulnerable species spread to areas in Italian and Greek waters where dedicated field research was limited or missing.

The Italia-Malta Interreg project Sea Marvel is the result of regional research collaboration involving the CBRG-UM and a research team from the University of Catania, led by Iuri Peri, expanding the field research effort in the central Mediterranean. This is necessary considering the increasing pressures in this region from vessel traffic, noise and other forms of pollution, including plastics and waste, overfishing by various countries and alien species increasing and affecting local species.

Many marine species are clearly risking becoming extinct

Sea Marvel researchers at the University of Malta, led by Vella, have been and continue to conduct extensive marine and aerial surveys to study the status of Maltese marine life and environment, while also involving stakeholders to contribute their experiences and sightings out at sea.

As part of ongoing research by the CBRG-UM, mariners were directed through Notice to Mariners no. 017 of 2022 to forward any sightings to complement long-term monitoring of various marine species, including dolphins, whales and turtles. Anyone wishing to contribute details may fill in the Google sighting form which is specifically for bottlenose dolphins and loggerhead turtles found in Maltese waters.

Sea-users are reminded that these species are legally protected and vessel distance needs to be kept from dolphins and turtles to avoid any harm to them. Ongoing research has recorded increasing disturbance and changes in coastal waters with limited integrated coastal zone management which, therefore, may affect their natural behaviours nega­tively. The lack of implementation of plans and enforcement to safeguard the many marine species that are clearly risking becoming extinct or have been listed as legally protected in local waters is another weakness that needs resolving.

Rich marine biodiversity means resilience and survival of species contributing to the mechanisms that not only maintain the sea alive but mitigate planet-wide problems, such as climate change. A world of knowledge is, therefore, required to understand and contribute to the best decisions and measures for conservation from local to global, with detailed studies that consider species, habitats and ecosystems.

Overfishing of the dusky grouper has led to a dangerous stock reduction.

The dusky grouper, Epinephelus marginatus, is an example that may highlight the contrast between lack of public awareness and urgent conservation needs. While this species is of economic importance locally in the fishing industry and is considered a culinary delicacy, the public is often not aware of its overexploitation that has caused dangerous stock reduction.

This is compounded by the fact that these groupers are top predators with a territorial behaviour so they easily fall victim to spearfishermen and other coastal fishing activities. Apart from direct removal of individuals from the shrinking population, harvesting groupers before sexual maturity severely impacts future population growth. As a result, the dusky grouper is listed as ‘endangered’ in the Mediterranean by the International Union for Conservation of Nature (IUCN).

Conservation of the slow growing dusky groupers requires detailed and long-term population research data, together with unbiased, accurate fish landings data and improved policies to enforce effective protection. This effort has been earmarked for many years by the CBRG-UM, which has also used genetics to study this species further.

Through numerous scuba-diving surveys, the presence, abundance and distribution of this fish in Maltese coastal waters was studied. Shockingly, although this species can grow up to 1.5m, the body size distribution peaked at 20-25cm, with only a few groupers larger than 55cm being recorded. Therefore, until this species remains on the list of fisheries’ target species, there is an urgent need to increase the minimum catch size limit for this species to over 49cm, which is reported as the average length at which females reach maturity, side by side with ‘no take zones’ in local marine protected areas to ensure possibilities for larger specimen to produce offspring. Both these strategies are essential to dusky grouper abundance and conservation in Maltese coastal waters. The species is already protected in many other Mediterranean waters.

While dusky groupers decline, alien fish are invading our seas, such as the pufferfish and lionfish, which seem to have very few potential predators except groupers. In fact, such issues were discussed at the Second International Symposium on Pufferfish and Lionfish in the Mediterranean, held in Turkey, where Vella was invited to give a keynote presentation, apart from contributing to the recommendations that came out from this effort.

The Sea Marvel project is also contributing to research on aliens and their efficient detection and mitigation to safeguard local marine biodiversity. Innovative techniques developed to efficiently inform and react to new challenges are supporting the future of conservation and the CBRG continues to contribute to this transformation.

World Oceans Day allows us to encourage everyone to consider ways of taking part in collective action for the conservation of our seas/oceans: from avoiding the disposal of waste on shores or overboard, to informing dedi­cated long-term researchers of their sightings in timely manner.

Adriana Vella is a professor and Martina Busuttil is a Sea Marvel scientific educator from the Conservation Biology Research Group, Biology Department, University of Malta. For more information, contact Vella at adriana.vella@um.edu.mt.