Biomass dynamics of primary producers provide a basis for assessing their capacity to capture carbon and mitigate excess greenhouse gases. Here, we estimate inter-annual and seasonal biomass cycles in canopy-forming Sargassaceae at 19 sites spanning ~ 200 km of the Ningaloo World Heritage Area over 11 consecutive years. Our global average summer estimate of 1.53 kg wet wt m −2 equates to 4.1–9.4 Gg of standing macroalgal carbo...

Plants occupying coastal ecosystems draw in carbon dioxide (CO 2 ) from the air and water around them during photosynthesis. A fraction of this CO 2 becomes fixed into plant biomass and can eventually contribute to the blue carbon pool—organic carbon (C org ) sequestered in slow‐turnover sinks. An important step in protecting and enhancing this natural carbon sequestration pathway is determining the relative contributions of d...

Scientists and managers rely on indicator taxa such as coral and macroalgal cover to evaluate the effects of human disturbance on coral reefs, often assuming a universally positive relationship between local human disturbance and macroalgae. Despite evidence that macroalgae respond to local stressors in diverse ways, there have been few efforts to evaluate relationships between specific macroalgae taxa and local human‐driven d...

Macroalgae‐dominated reefs are a prominent habitat in tropical seascapes that support a diversity of fishes, including fishery target species. To what extent, then, do macroalgal habitats contribute to small‐scale tropical reef fisheries? To address this question we: (1) Quantified the macroalgae‐associated fish component in catches from 133 small‐scale fisheries, (2) Compared life‐history traits relevant to fishing (e.g. grow...

Secondary production connects primary producers with higher‐order consumers. The response of secondary production to seasonal variation in primary producers can influence trophic flows that underpin key ecosystem functions and services. Within the canopy‐forming macroalgal meadows of Ningaloo Reef, Western Australia, we quantified the secondary production generated by Sargassum‐ associated epifauna across seasons and seascapes...

Dam construction is a major driver of ecological change in freshwater ecosystems. Fish populations have been shown to diverge in response to different flow velocity habitats, yet adaptations of fish populations to river and reservoir habitats created by dams remains poorly understood. We aimed to evaluate divergence of morphological traits and prolonged swimming speed performance between lotic and lentic populations of Austral...

Canopy‐forming macroalgae can construct extensive meadow habitats in tropical seascapes occupied by fishes that span a diversity of taxa, life‐history stages and ecological roles. Our synthesis assessed whether these tropical macroalgal habitats have unique fish assemblages, provide fish nurseries and support local fisheries. We also applied a meta‐analysis of independent surveys across 23 tropical reef locations in 11 countri...

Identifying and protecting nursery habitats for species is a key conservation strategy for the long‐term sustainability of populations. In tropical ecosystems, macroalgal habitats have recently been identified as nurseries for fish of commercial and conservation significance. Here, we explore how local‐scale variations in seaweed habitat quality interact with large‐scale climatic conditions (Southern Oscillation Index, SOI) to...

Aim The dispersal and distribution patterns of many marine organisms are driven by oceanographic conditions, which are influenced by global climate. Climate‐driven oceanographic changes are thus likely to result in biogeographical changes. We assess how recent and predicted oceanographic changes affect the dispersal capacities and distributions of ecologically important (especially habitat‐forming) marine organisms. Location W...