Sponge Response Mechanisms to Climate Change

Sponges occupy key positions in benthic ecosystems, performing critical roles in nutrient cycling, habitat formation and water filtration. Under climate change stressors such as ocean warming, acidification and more frequent heatwaves, sponges exhibit a suite of interlinked response mechanisms spanning morphology, physiology, molecular regulation and symbiotic interactions. Physiologically, sponges may adjust respiration and feeding rates to cope with altered temperature and pH regimes, though elevated temperatures often induce tissue necrosis and reduced clearance efficiency. Morphological plasticity, including changes to skeletal elements (spicules) and tissue density, can confer resilience to acidified waters. At the cellular level, heat‐shock proteins, antioxidant pathways and apoptosis regulators are mobilised to maintain homeostasis under thermal stress. Molecular studies reveal shifts in transcriptomes linked to signal transduction, immune response and protein repair, indicating a capacity for acclimation or preconditioning. Crucially, most sponges function as holobionts—complex assemblages of host and microbial symbionts—and dysbiosis of these communities under warming and acidification can compromise nutrient exchange and nitrogen cycling, magnifying host vulnerability. Understanding these multifaceted responses is essential for predicting sponge persistence, informing reef restoration efforts and refining models of carbon flux under future ocean scenarios.

Research from Nature Portfolio

Investigations into calcareous sponges demonstrate that primmorph aggregates of Paraleucilla magna retain the ability to synthesise spicules under acidified conditions (pH 7.6), with only minor reductions in skeletal thickness. This suggests a degree of skeletal resilience in near-future ocean acidification scenarios. Studies on the glass sponge Aphrocallistes vastus reveal that combined warming and acidification markedly impair pumping capacity and induce irreversible tissue withdrawal, while weakening skeletal stiffness, threatening reef formation in the Northeast Pacific. Foundational work on the boreal deep-sea sponge Geodia barretti shows that acute temperature increases double respiration and nitrogen efflux and elevate cellular stress indicators, yet the microbiome remains stable; these physiological shifts underline potential thresholds beyond which metabolic imbalance and mortality may occur.

Sponge Response Mechanisms to Climate Change publication trend

The graph below shows the total number of articles in sponge response mechanisms to climate change across all publications each year (not limited to Nature Index journals).

Technical terms

Holobiont: The host organism together with its associated microbial community, functioning as a single ecological unit.

Dysbiosis: A disturbed or imbalanced microbial assemblage that can impair host health and nutrient exchange.

Spicule: A microscopic skeletal element composed of silica or calcium carbonate that provides structural support within a sponge.

Ocean acidification (OA): The decrease in seawater pH due to increased absorption of atmospheric CO₂, affecting calcification and metabolic processes.

Heat‐shock proteins (HSPs): Molecular chaperones induced by thermal stress that assist in protein folding and prevent aggregation.

Clearance rate: The volume of water filtered by a sponge per unit time, reflecting feeding efficiency and ecological function.

Nitrogen cycling: The transformation of nitrogen compounds (e.g., ammonia to nitrate) mediated by host and microbial metabolism, essential for nutrient balance.

References

1. Calcareous sponges can synthesize their skeleton under short-term ocean acidification. Scientific Reports (2023).
2. Warming and acidification threaten glass sponge Aphrocallistes vastus pumping and reef formation. Scientific Reports (2020).
3. The response of a boreal deep-sea sponge holobiont to acute thermal stress. Scientific Reports (2017).
4. Future ocean conditions induce necrosis, microbial dysbiosis and nutrient cycling imbalance in the reef sponge Stylissa flabelliformis. ISME Communications (2023).
5. Marine heatwave conditions drive carryover effects in a temperate sponge microbiome and developmental performance. Proceedings of the Royal Society B (2023).
6. Effect of Acute Thermal Stress Exposure on Ecophysiological Traits of the Mediterranean Sponge Chondrilla nucula: Implications for Climate Change. Biology (2023).