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The condition of fish relates to their energy reserves, and a suite of proxies exist to approximate condition, including biochemical and morphometric indices. Biochemical indices directly measure energy stores but are expensive and sometimes lethal. Morphometrics offer several advantages, but their utility as condition proxies is debated and largely untested experimentally. Here, we manipulated the condition of yellowfin bream (Acanthopagrus australis, Günther, 1859) via food reduction to simulate the effect of poor habitat quality and calculated a variety of condition indices through time. We measured four non‐lethal morphometrics (Fulton's K, Le Cren's relative condition, width‐to‐length ratio and girth), the hepatosomatic index and a biochemical benchmark (liver lipid content). Girth and width‐to‐length ratio were reasonably well correlated with lipid content (R2 = 0.74 and 0.56, respectively). The hepatosomatic index was only weakly or uncorrelated to other indices, including lipid content (R2 = 0.35). Where precise estimates of body condition are not needed or repeat measures on the same individual are useful, non‐lethal morphometrics provide a fast, cheap and non‐lethal alternative to biochemical and lethal morphometric methods for this species. We finish by outlining how artificial intelligence‐based automation can be combined with morphometrics to further enhance ethical monitoring by eliminating the need to capture and handle fish entirely. [ABSTRACT FROM AUTHOR]

Seagrass meadows are threatened by multiple pressures, jeopardizing the many benefits they provide to humanity and biodiversity, including climate regulation and food provision through fisheries production. Conservation of seagrass requires identification of the main pressures contributing to loss and the regions most at risk of ongoing loss. Here, we model trajectories of seagrass change at the global scale and show they are related to multiple anthropogenic pressures but that trajectories vary widely with seagrass life-history strategies. Rapidly declining trajectories of seagrass meadow extent (>25% loss from 2000 to 2010) were most strongly associated with high pressures from destructive demersal fishing and poor water quality. Conversely, seagrass meadow extent was more likely to be increasing when these two pressures were low. Meadows dominated by seagrasses with persistent life-history strategies tended to have slowly changing or stable trajectories, while those with opportunistic species were more variable, with a higher probability of either rapidly declining or rapidly increasing. Global predictions of regions most at risk for decline show high-risk areas in Europe, North America, Japan, and southeast Asia, including places where comprehensive long-term monitoring data are lacking. Our results highlight where seagrass loss may be occurring unnoticed and where urgent conservation interventions are required to reverse loss and sustain their essential services. [ABSTRACT FROM AUTHOR]