Climate Crisis: Ocean’s Fragile Fortresses Are Crumbling

Welcome, Net Zero News readers,

In an era where the impacts of climate change are becoming increasingly evident, a recent study sheds light on the intricate and often overlooked world of bryozoans—colonial invertebrates that play a crucial role in forming marine habitats. Conducted by a dedicated research team from the Institut de Ciències del Mar (ICM-CSIC), this groundbreaking study published in Communications Biology explores how ocean acidification and warming, two significant consequences of climate change, affect these vital organisms.

The “False Coral”: A Key Player in Marine Ecosystems

One of the primary subjects of this study is Myriapora truncata, commonly known as “false coral.” This species is widely distributed throughout the Mediterranean and is known for its ability to create three-dimensional structures that provide essential shelter for various marine species. While corals often receive the spotlight as the primary architects of marine habitats, bryozoans like false corals are equally important, yet they frequently remain underrepresented in ecological studies focused on environmental change.

The lead author of the study, Blanca Figuerola, an ICM-CSIC researcher, highlights the significance of this research. “Despite being part of a different phylum, bryozoans are incredibly diverse and abundant globally,” she explains. “These small architects of the sea are often overlooked, and our study opens a new window to better understand how they may respond to the rapid changes occurring in our oceans.”

Exploring the Unexplored: The Microbiome of Bryozoans

One of the most notable aspects of this research is its focus on the microbiome of Myriapora truncata. Until now, the microbiomes of bryozoans had remained virtually unexplored, leaving a significant gap in our understanding of these organisms’ responses to environmental stressors. Figuerola emphasises that bryozoans hold substantial ecological importance, yet little was known about how they react to the combined effects of ocean acidification and warming.

A Natural Laboratory: Ischia, Italy

To investigate these effects, the research team utilised a unique “natural laboratory” on the island of Ischia, Italy. Here, volcanic CO2 bubbles from the seabed simulate the ocean acidification conditions projected for the end of the century. “This area provides a remarkable opportunity to study how marine species respond to acidification under natural conditions,” explains Núria Teixidó, a researcher at the Stazione Zoologica Anton Dohrn and the study’s last author.

By comparing the morphology, skeletal mineralogy, and microbiome of bryozoan colonies exposed to these acidifying conditions with those that were not, the researchers observed significant differences. The results indicated that while these species exhibit some capacity for acclimation—modifying their skeletal mineralogy to enhance resistance—their microbiomes suffered a loss in functional diversity. “We noted a decline in genera that are potentially involved in key processes such as nutrition, defence, or environmental stress resistance,” Figuerola states.

Warming’s Amplifying Effects

The study also monitored the effects of rising temperatures over a five-year period, a critical factor in the ongoing climate crisis. “Our models indicate that the combination of ocean acidification and warming intensifies the effects observed, resulting in a significant reduction in the coverage of encrusting bryozoans and an increase in mortality rates,” says Pol Capdevila, a researcher at the University of Barcelona. Although the bryozoans displayed some morphological plasticity, it proved insufficient to counteract the combined impacts of these environmental stressors.

Advanced Techniques for Groundbreaking Results

To reach these conclusions, the research team employed advanced techniques, including modelling and computed microtomography, to create three-dimensional images of the internal skeletal structures of the bryozoan species. These images not only serve as valuable resources for ongoing research but also play a pivotal role in science communication and environmental education. The team is currently collaborating with Cooked Illustrations, a visual storytelling studio, to develop an engaging science animation aimed at both the general public and educational audiences.

Implications for Marine Conservation

The findings of this research hold significant implications for the management and conservation of Mediterranean marine ecosystems, particularly in the context of climate change. Habitat-forming species like bryozoans are not only vulnerable to environmental changes; their potential disappearance could trigger cascading effects throughout the marine food web, impacting numerous species that rely on these organisms for shelter and sustenance.

Furthermore, the study’s characterisation of the bryozoan microbiome and the preliminary identification of beneficial microorganisms open new research avenues aimed at enhancing the resilience of holobionts—combinations of hosts and their associated microbiomes—through nature-based solutions.

A Call for Interdisciplinary Approaches

This vital research is part of a broader initiative under the MedCalRes National Plan project, which is now being carried forward through the HOLOCHANGE consolidation project and the National Plan MedAcidWarm. These initiatives aim to deepen our understanding of bryozoan-microbiome interactions to better anticipate and mitigate the impacts of climate change.

As Figuerola concludes, “The complexity of the issue demands integrated analyses. This study exemplifies how interdisciplinary approaches can assist us in anticipating future scenarios and in more effectively protecting our marine ecosystems.”

As we continue to grapple with the challenges posed by climate change, this research highlights the importance of exploring every facet of marine life, especially those that play crucial roles in sustaining marine environments. The resilience of our oceans may well depend on the unseen connections within these ecosystems, making studies like this not only relevant but essential for future conservation efforts.

Stay tuned for more insights and updates on marine conservation and climate change, as we continue to explore the pathways toward a sustainable future. Together, we can champion the cause of net zero and protect the vibrant ecosystems that thrive beneath the waves.