The 2025 Starfish Barometer

<strong class="journal-contentHeaderColor">Abstract.</strong> The Ocean is essential to life on Earth, regulates the climate, supports rich biodiversity, sustains livelihoods, and inspires cultures and societies. However, unregulated human impacts are putting the Ocean and its ability to contribute to humanity at risk. The Starfish Barometer is a new initiative launched on World Ocean Day (8 June 2025) to provide a concise, science-based annual overview of the multiple dimensions of the Ocean through the lens of its interdependence with humanity. Each year, the Starfish Barometer will present a carefully curated selection of Ocean-related developments, chosen for their global significance and grounded in the most up-to-date scientific evidence, intended for a broad non-specialist audience. Rather than offering an exhaustive review, it will spotlight key aspects, robust, evidence-based, and reflective of major developments of the year. The Starfish Barometer emphasizes the two-way relationship between humanity and the Ocean: we impact its future, and it shapes ours. Its distinctive format, a five-armed starfish with the current state of the Ocean on the top arm, visually represents the balance conveyed by the four remaining arms: human-induced pressures that are undermining Ocean health, the resulting harms to society, the Ocean protection efforts underway, and the opportunities that the Ocean continues to offer to humanity. Key figures from the 2025 edition illustrate the alarming state of the Ocean. Sea level has risen by 23 cm since 1901; in 2023 alone, the losses from tropical storms and flooding totalled USD 102 billion. The 2024 Ocean temperatures broke the 64-year record, with sea-surface temperature and marine heatwaves showing a marked increase globally. Marine animal food production reached a record <span class="inline-formula">115×10⁶</span> t in 2022, yet 37.7 % of fish stocks remain overexploited, highlighting the urgent need for sustainable practices. Declared protection policies currently cover 8.34 % of the Ocean's surface, while marine biodiversity is under threat, with now 1677 marine species recorded as being at risk of extinction.