Marine heatwaves are extreme events that can have profound and lasting impacts on marine species. Field observations have shown seaweeds to be highly susceptible to marine heatwaves, but the physiological drivers of this susceptibility are poorly understood. Furthermore, the effects of marine heatwaves in conjunction with ocean warming and acidification are yet to be investigated. To address this knowledge gap, we conducted a laboratory culture experiment in which we tested the growth and physiological responses of Phyllospora comosa juveniles from the southern extent of its range (43 - 31° S) to marine heatwaves, ocean warming and acidification. We used a "collapsed factorial design" in which marine heatwaves were superimposed on current (today's pH and temperature) and future (pH and temperature projected by 2100) ocean conditions. Responses were tested both during the heatwaves, and after a seven-day recovery period. Heatwaves reduced net photosynthetic rates in both current and future conditions, while respiration rates were elevated under heatwaves in the current conditions only. Following the recovery period, there was little evidence of heatwaves having lasting negative effects on growth, photosynthesis or respiration. Exposure to heatwaves, future ocean conditions or both caused an increase in the degree of saturation of fatty acids. This adjustment may have counteracted negative effects of elevated temperatures by decreasing membrane fluidity, which increases at higher temperatures. Furthermore, P. comosa appeared to down-regulate the energetically expensive carbon-concentrating mechanism (CCM) in the future conditions with a reduction in δ13 C values detected in these treatments. Any saved energy arising from this down-regulation was not invested in growth and was likely invested in the adjustment of fatty acid composition. This adjustment is a mechanism by which P. comosa and other seaweeds may tolerate the negative effects of ocean warming and marine heatwaves through benefits arising from ocean acidification.

The Marine Futures Project was designed to benchmark the current status of key Western Australian marine ecosystems, based on an improved understanding of the relationship between marine habitats, biodiversity and our use of these values. Approximately 1,500 km2 of seafloor were mapped using hydroacoustics (Reson 8101 Multibeam), and expected benthic habitats "ground-truthed" using towed video transects and baited remote underwater video systems. Both sources of information were then combined in a spatial predictive modelling framework to produce fine-scale habitat maps showing the extent of substrate types, biotic formations, etc. Surveys took place across 9 study areas, including Broke Inlet, a relatively remote area 400km south of Perth, between the towns of Augusta and Albany. The nearest major town, Manjimup, is situated 100km north and the small coastal settlement Windy Harbour approximately 30km west of Broke Inlet. The Inlet is entirely surrounded by the D’Entrecasteaux National Park, which is accessible via a sealed road and attracts limited ‘through-traffic’ to the area. The marine environment off Broke is one fairly untouched by major tourism pressures and thus this location was selected due to its relative inaccessibility.

The spatial extent of C. rodgersii "barrens" was estimated by surveying rocky reef habitat with a towed underwater video system. Sampling took place at 13 regions along the east coast of Tasmania, each comprising 3 subsites, this dataset refers to the Eddystone Point region, and its 3 subsites: Georges Bay, Lighthouse Point and Purdon.

NESP Marine Biodiversity Hub Project E7. Results from the outplanting of lab-selected and cultivated warm-adapted genotypes of giant kelp (Macrocystis pyrifera), at two trial restoration sites. A third restoration trial site had no surviving kelp, so those data were not included here. Data and details from lab-selection experiments can be found in the associated dataset - "NESP Marine Hub Project E7 - Macrocystis pyrifera thermal tolerance testing" https://metadata.imas.utas.edu.au/geonetwork/srv/eng/catalog.search#/metadata/0b91d7fd-7d29-452f-954a-78cf75151035

1. Seabird species worldwide are integral to both marine and terrestrial environments, connecting the two systems by transporting vast quantities of marine-derived nutrients and pollutants to terrestrial breeding, roosting, and nesting grounds via the deposition of guano and other allochthonous inputs (e.g., eggs, feathers). 2. We conducted a systematic review and meta-analysis and provide insight into what types of nutrients and pollutants seabirds are transporting, the influence these subsidies are having on recipient environments, with a particular focus on soil, and what may happen if seabird populations decline. 3. The addition of guano to colony soils substantially increased nutrient levels compared to control soils for all seabirds studied, with cascading positive effects observed across a range of habitats. Deposited guano sometimes led to negative impacts, such a guanotrophication, or guano-induced eutrophication, which was often observed where there was an excess of guano or in areas with high seabird densities. 4. While the literature describing nutrients transported by seabirds is extensive, literature regarding pollutant transfer is comparatively limited, with a focus on toxic and bioaccumulative metals. Research on persistent organic pollutants and plastics transported by seabirds is likely to increase in coming years. 5. Studies were limited geographically, with hotspots of research activity in a few locations, but data were lacking from large regions around the world. Studies were also limited to seabird species generally listed as Least Concern on the IUCN Red List. As seabird populations are impacted by multiple threats and steep declines have been observed for many species worldwide, gaps in the literature are particularly concerning. The loss of seabirds will impact nutrient cycling at localised levels and potentially on a global scale as well, yet it is unknown what may truly happen to areas that rely on seabirds if these populations disappear. The information in this record includes three spreadsheets and R code. Descriptions are included below: - The spreadsheets contain all information extracted from the publications that were critically reviewed (n = 181). The first spreadsheet contains information regarding each publication (1 publication per row), such as study location, sampling methods. The second spreadsheet contains information about the seabird species studied in each publication (1 row per seabird species per publication). The third spreadsheet contains data for the meta-analysis (1 row per publication, except if the publication studied multiple species, then it would be 1 row per species per publication). - The R code is for the meta-analyses that were undertaken. Comments are included within the code plus detailed information can be found in the Methods section of the paper.