Potential Effects of Harmful Algal Blooms on Bivalve Reproductive Output

Harmful algal blooms (HABs) pose significant threats to marine ecosystems, human health, and coastal economies worldwide. These blooms often coincide with the breeding periods of bivalves, adversely affecting their reproductive output. Bivalve aquaculture, which is crucial for food security and coastal economies, is particularly vulnerable to these effects, threatening the sustainable production of cultivated bivalve species. Despite extensive research on HAB-related toxins and their implications for food safety, the broader physiological effects on bivalve reproductive health remain poorly understood. With HABs increasing in frequency due to global changes, investigating their impacts on bivalve reproduction is essential for addressing the resulting ecological and socioeconomic challenges. The PERIL project aims to assess the impact of regularly blooming and emerging HAB species in European waters on the reproduction and early developmental stages of commercially and ecologically important bivalves. Specifically, the project will elucidate the toxicity of HABs on bivalve gametes through both direct and parental exposure. The mechanisms affected by HAB exposure during bivalve gametogenesis, embryo-larval development, and the parental transmission of traits to offspring will be thoroughly investigated. To achieve these objectives, a novel integrative approach will be employed, encompassing physiological, cellular, molecular, and epigenetic analyses. Overall, PERIL represents a pivotal step toward a comprehensive understanding of HAB phenomena on bivalve population renewal. It will generate data to support the development of a standardized bioassay, which will serve as an innovative tool for assessing the reproductive toxicity of HABs. This approach has the potential to revolutionize strategies for bivalve conservation, restoration, and aquaculture.