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• We apply the Red List of Ecosystems framework to connected coastal wetlands. • Moreton Bay mangroves and seagrass were Least Concern; saltmarsh was Endangered. • Assessments of individual ecosystems can misrepresent risk of collapse. • Collapse in any one ecosystem can have seascape-wide consequences. • Integrating outcomes for connected ecosystems is thus important. Human-induced habitat clearing and pollution are leading drivers of biodiversity loss. Ecosystem assessments are required to identify ecosystems at risk of collapse, but they should account for cross-system linkages and dynamics where necessary. This is particularly true for coastal wetlands (e.g. seagrass, mangroves and saltmarsh), which exhibit high ecological connectivity and have individually suffered global declines over the last century. We use the coastal wetlands of Moreton Bay, Queensland, Australia, as a model system to examine how integrating outcomes of multiple, simultaneously conducted, ecosystem assessments can assist in identifying appropriate management and conservation strategies. We simultaneously conducted separate assessments of seagrass, mangrove and saltmarsh ecosystems against the IUCN Red List of Ecosystems criteria. Despite substantial human population growth in the region, seagrass and mangroves were assessed as Least Concern. Mangroves were found to be rapidly encroaching on saltmarsh. This process, together with past clearing, were the major drivers behind saltmarsh being assessed as Endangered. Given the importance of connectivity among these connected ecosystems, collapse in any one ecosystem can have seascape-wide consequences, highlighting the benefit of conducting multi-ecosystem assessments. Consequently, a fully integrated assessment of the coastal wetlands as a single entity would miss key processes, such as mangrove encroachment, potentially underestimating overall risks. Our study highlights the plight of saltmarsh and the value of conducting simultaneous RLE assessments for multiple ecosystems comprising seascapes. We recommend that connectivity be accounted for explicitly in assessments of other connected, high-risk ecosystems. [ABSTRACT FROM AUTHOR]

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]