Rising sea temperatures are placing increasing pressure on Mediterranean gorgonians, important marine organisms that create complex underwater habitats and provide shelter for numerous species. The issue was among the central topics at HIC Summit Ibiza 2026, where scientists and conservation specialists discussed the future of marine ecosystems and the role of coastal tourism destinations in protecting them.

The event, held from 28 to 30 October, brought together international experts to examine sustainability, biodiversity, the blue economy and regenerative tourism. During the marine conservation programme on 29 October at TheHUB Ibiza in Santa Eulària, Marc Rigau, chief executive of the Blue Life Foundation, highlighted the vulnerability of gorgonians and the need to give greater attention to these relatively little-known organisms.

Scientific research increasingly demonstrates the effects of marine heatwaves on gorgonian populations across the Mediterranean. Studies have documented substantial biomass losses following prolonged exposure to unusually high sea temperatures, while more recent research has identified additional risks to their reproduction and physiological health.

What Are Mediterranean Gorgonians?

Gorgonians are colonial marine animals belonging to the octocorals, a group of organisms related to corals. Their branching structures can resemble underwater trees, forming complex habitats on rocky seabeds.

These structures provide shelter and living space for fish, invertebrates and other marine organisms. Their presence therefore contributes to the biodiversity and ecological functioning of the seabed.

The red gorgonian, scientifically known as Paramuricea clavata, is one of the Mediterranean's most important habitat-forming species. Its slow growth and long life cycle make populations particularly vulnerable when repeated environmental disturbances prevent them from recovering.

Despite their ecological importance, gorgonians remain less familiar to many people than Posidonia oceanica, the seagrass that forms extensive underwater meadows around Ibiza and Formentera.

During the HIC Summit discussion, Rigau highlighted the need to increase public awareness of these organisms and their contribution to Mediterranean marine biodiversity.

Research Documents Significant Biomass Losses

The scientific evidence behind concerns about gorgonian populations includes long-term research conducted by the Institute of Marine Sciences (ICM-CSIC) and the University of Barcelona.

A study published in 2021 examined populations of red gorgonians in the Scandola Marine Protected Area in Corsica, following a major marine heatwave in 2003.

Researchers monitored the populations over the following 15 years. By 2017, the average biomass of the studied red gorgonian populations had declined by approximately 80% compared with the levels recorded in 2003.

The research showed that the populations had failed to recover their initial biomass, despite the passage of more than a decade.

This figure relates specifically to the populations examined in Corsica. It should not be interpreted as an estimate of losses in Ibiza or across the entire Mediterranean.

A further study published in August 2026 provides a broader picture of the problem. Researchers analysed more than two decades of monitoring data from 49 shallow-water red gorgonian populations across the north-western Mediterranean.

The study estimated a median regional biomass decline of 45% over approximately two decades. It also found that increasingly frequent marine heatwaves were associated with widespread mortality and limited evidence of recovery.

The researchers concluded that marine protected areas can help maintain higher overall biomass, but local protection alone cannot offset the effects of climate-driven mortality.

Warmer Water Is Also Disrupting Reproduction

The effects of rising temperatures extend beyond the immediate damage caused by marine heatwaves.

Research published in February 2026 by scientists from the University of Barcelona and ICM-CSIC found that a temperature increase of 2°C advanced the reproductive cycle of red gorgonians by approximately two weeks under the conditions studied.

The timing of reproduction is important because gorgonian colonies release eggs and sperm into the water, leading to fertilisation and the development of larvae that eventually settle on the seabed and form new colonies.

The researchers found that the earlier reproductive timing reduced larval biomass, leaving larvae with less energy. It also increased larval mortality and reduced their success in attaching to the seabed.

These effects could make it more difficult for populations to recover after major mortality events.

The research combined observations in the Montgrí Natural Park, the Medes Islands and Baix Ter with laboratory experiments. It did not directly measure reproductive changes in Ibiza's gorgonian populations.

Microplastic Pollution Adds Another Environmental Pressure

Temperature increases are not the only concern for Mediterranean gorgonians.

A study published in March 2026 by the University of Barcelona examined the effects of prolonged microplastic exposure on two species: the white gorgonian (Eunicella singularis) and the red gorgonian (Paramuricea clavata).

During a three-month experiment, researchers exposed colonies to mixtures of common plastic particles, including polyethylene terephthalate, polystyrene and polypropylene.

The results showed significantly reduced respiration rates in both species, suggesting a reduction in metabolic activity.

However, the researchers did not observe visible tissue damage or structural changes in the colonies examined. Feeding behaviour and organic matter content also remained stable during the experiment.

The findings indicate that microplastic exposure can affect the physiology of gorgonians even when visible damage is absent. The researchers emphasised that further work is needed to understand the longer-term ecological consequences, particularly when plastic pollution occurs alongside other environmental pressures such as warming seas.

Blue Life Foundation Highlights Conservation Work in Ibiza

During the HIC Summit, Marc Rigau outlined the work being carried out by the Blue Life Foundation in Ibiza to conserve and restore gorgonian populations and Posidonia oceanica meadows.

The initiatives were presented as part of a wider effort to protect the island's marine environment, with support from the Abel Matutes Foundation.

The discussion also highlighted the importance of prioritising conservation before ecosystems become severely degraded.

This is particularly relevant for gorgonians because their slow growth and limited recovery capacity mean that restoring damaged populations can take many years. Preventing damage in the first place is therefore an important part of protecting these habitats.

For Ibiza, the issue is relevant not only to marine biodiversity but also to the health of the underwater landscapes that contribute to the island's natural environment.

Marine Conservation Takes Centre Stage at HIC Summit Ibiza

The marine conservation programme formed part of the eighth HIC Summit, held across three locations in Ibiza between 28 and 30 October 2026.

The 29 October session at TheHUB Ibiza brought together specialists from research institutions, conservation organisations, tourism businesses and public bodies to discuss the relationship between healthy marine ecosystems and sustainable coastal destinations.

Contributors included representatives of the Blue Life Foundation, the Port Authority of Vigo, the Polytechnic University of Cartagena and the Jumeirah Group.

The programme also explored examples of conservation initiatives from other destinations, including the Dubai Turtle Rehabilitation Project and the environmental approach adopted by Seychelles.

The event sought to encourage cooperation between scientific institutions, public authorities and the tourism sector, recognising that protecting marine environments requires action beyond individual conservation projects.

Protecting Marine Ecosystems Before Damage Becomes Irreversible

The research presented and discussed around HIC Summit highlights the growing pressure on Mediterranean gorgonians from marine heatwaves, changing reproductive cycles and pollution.

Although the scientific studies cover different locations and experimental conditions, they point towards a common challenge: these habitat-forming organisms have limited capacity to recover when environmental pressures occur repeatedly.

For Ibiza, improving awareness of gorgonians and supporting marine conservation initiatives can help bring greater attention to an important part of the island's underwater biodiversity.

As sea temperatures continue to rise, protecting existing marine habitats and reducing additional pressures will be increasingly important for the long-term health of the Mediterranean.