Marine pufferfishes are globally distributed and ecologically important organism notable for accumulating tetrodotoxin [TTX], a potent neurotoxin with wide ecological ramifica-tions. Unlike many endogenous defences, TTX in pufferfishes is acquired indirectly via microbial and trophic pathways, linking pufferfish toxicity to the dynamics of marine mi-crobial assemblages and food webs. Anthropogenic climate change principally ocean warming, deoxygenation, and acidification is rapidly reshaping marine environments in ways that are likely to intensify and redistribute TTX exposure. Observational and experimental studies indicate that elevated seawater temperatures favour the proliferation of thermophilic, toxin-producing bacteria [e.g., Vibrio spp.], increase the abundance of toxic prey, and raise TTX burdens in pufferfish tissues seasonally and spatially. Concurrently, warming-driven range shifts have promoted poleward expansions of several tropical and subtropical puffer species, producing novel sympatric assemblages, hybridization events, and “cryptic” toxic phenotypes that complicate species identification and risk assess-ment. These biogeographic rearrangements, together with altered prey communities and microbial composition, reconfigure the trophic pathways by which TTX is transferred and concentrated in higher trophic levels. Early evidence also links multistressor conditions elevated temperature combined with hypoxia or acidification to altered developmental success and changes in toxin allocation during reproduction, suggesting potential popu-lation-level consequences. This review synthesizes current global evidence on cli-mate-linked changes in pufferfish TTX dynamics, integrating microbial ecology, trophic transfer, life-history shifts, and biogeography. We highlight [i] mechanistic pathways by which warming and associated ocean changes increase environmental TTX availability, [ii] how shifting species ranges and hybridization alter toxicity patterns across regions, and [iii] key methodological advances [e.g., high-resolution LC-MS/MS, metagenomics] needed to resolve open questions. We identify critical research gaps long-term field moni-toring, integrated microbial–trophic mapping, and multistressor population studies and recommend synthesis strategies that link environmental monitoring to toxin surveillance. Understanding pufferfish toxification as a climate-sensitive ecological process [not a static species trait] is essential to anticipate how marine toxin landscapes will change in the Anthropocene and to develop timely, science-based monitoring frameworks.
Choudhary G., Hamdani A., Unno H., Kimura M. & Venmathi Maran B. A., 2026. Climate change is redefining tetrodotoxin accumulation and ecological dynamics in pufferfishes. Preprints. Article.
0 Responses to “Climate change is redefining tetrodotoxin accumulation and ecological dynamics in pufferfishes”