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Marine kelp forests cover 1/3 of our world's coastlines, are heralded as a nature-based solution to address socio-environmental issues, connect hundreds of millions of people with the ocean, and support a rich web of biodiversity throughout our oceans. But they are increasingly threatened with some areas reporting over 90% declines in kelp forest cover in living memory. Despite their importance and the threats they face, kelp forests are entirely absent from the international conservation dialogue. No international laws, policies, or targets focus on kelp forests and very few countries consider them in their national policy. The Kelp Forest Challenge addresses that gap. Together with 252 kelp experts, professionals, and citizens from 25 countries, the Kelp Forest Challenge was developed as a grassroots vision of what the world can achieve for kelp forest conservation. It is a global call to restore 1 million and protect 3 million hectares of kelp forests by 2040. This is a monumental challenge, that will require coordination across multiple levels of society and the mobilization of immense resources. Pledges may therefore include area for protection or restoration, enabling pledges which assist in conservation (funding, equipment, professional expertise, capacity building), or awareness-based pledges which increase awareness or education about kelp forests. Correspondingly, participants may be from government, scientific institutions, private sector, NGOs, community groups, or individuals. This challenge is the beginning of a 17-year mission to save our kelp forests and anyone and any organisation is invited to participate. [ABSTRACT FROM AUTHOR]

Seaweeds are rich in essential dietary minerals, often lacking in terrestrial plant foods, with interest in Australian seaweeds rapidly increasing. We screened six Australian brown seaweeds with commercial potential for dietary mineral composition: Cystophora torulosa, Caulocystis uvifera, Durvillaea potatorum, Ecklonia radiata, Hormosira banksii and Phyllospora comosa. Spatial replicates of each species were collected from three non-urbanised sites remote from pollution sources and processed for human consumption. Dried samples were analysed by inductively coupled plasma mass spectrometry (ICP-MS) for 12 essential dietary minerals. Overall dietary mineral composition differed significantly amongst all species, except between sargassaceous species C. torulosa and C. uvifera; but concentrations of individual elements varied in complex ways. All species investigated had high concentrations of dietary minerals essential for optimal human health if consumed in realistic quantities (e.g. 10 g day−1 DW) as part of balanced diets, including the most common dietary minerals deficient in humans (iodine, iron, zinc, magnesium, calcium and selenium): iodine (888 ± 100 mg kg−1 DW) and zinc were highest in P. comosa; iron and calcium were highest in C. torulosa, but calcium was also high in E. radiata, H. banksii and D. potatorum; magnesium was highest in H. banksii, D. potatorum and P. comosa; selenium concentrations exceeded those previously reported for seaweeds for all species, except D. potatorum. The best nutritional outcomes may be achieved by regularly consumption of a diversity of seaweed species. However, further investigation into ways to reduce iodine content in some species may be required to maximise health benefits from regular consumption of these Australian seaweeds. [ABSTRACT FROM AUTHOR]

We found that an innovative nursery approach, where Lessonia corrugata seeded spools were cultivated by spinning to increase the water motion relative to non-spinning spools, had higher growth in both the nursery and at-sea stages. Using this method, we compared the at-sea growth of sporophytes cultivated on spinning spools at different depths (1 m, 3 m, 5 m) and seasons (timing of out-planting). Finally, we compared the at-sea growth of sporophytes cultivated on spinning spools vs. non-spinning sporophytes at 3-m depth. In the nursery, sporophytes on spinning spools developed significantly faster than those on non-spinning spools: blade length was 4.6 and 2.5 cm, and holdfast area was 0.10 and 0.03 cm2 for spinning and non-spinning spools, respectively. At-sea L. corrugata in spring had significantly greater biomass production at 3 m and 5 m (3.0 kg m−1 and 2.4 kg m−1, respectively) and up to 96% survival. In summer, 100% of deployed kelps died at all depths. Growth was faster at 5 m (0.3 ± 0.06 kg m−1) in autumn and at 3 and 5 m (1.1 ± 0.1 kg m−1 and 0.8 ± 0.1 kg m−1, respectively) in winter. At sea, sporophytes from the spinning spools grew significantly 60% larger, and survival was ~ 3 times greater over 3 months than sporophytes from non-spinning. Overall, this study shows that spinning seeded spools in the nursery improves the growth at sea, spring is the best season for out-planting L. corrugata, and 3 or 5 m depth is best for production. [ABSTRACT FROM AUTHOR]

A STEM-based faculty in an Australian university leveraged online educational technology to help address student and academic concerns associated with team-based assessment. When engagement and contribution of all team members cannot be assured, team-based assessment can become an unfair and inaccurate measure of student competency. This case study explores the design and capacity of an online self and intra-team peer-assessment of teamwork strategy to measure student engagement and enable peers to hold each other accountable during team-based assessments. Analysis of student interactions across 39 subjects that implemented the strategy in 2020, revealed that an average of 94.4% of students completed the self and intra-team peer-assessment task when designed as part of a summative team-based assessment. The analysis also revealed that an average of 10.3% of students were held accountable by their peers, receiving feedback indicating their teamwork skills and behaviours were below the required minimum standard. Furthermore, the strategy was successfully implemented in cohorts ranging from seven to over 700 students, demonstrating scalability. Thus, this online self and intra-team peer-assessment strategy provided teaching teams with evidence of student engagement in a team-based assessment while also enabling students to hold each other accountable for contributing to the team task. Lastly, as the online strategy pairs with any discipline-specific team-based assessment, it provided the faculty with a method that could be used consistently across its schools to support management and engagement in team-based assessments. [ABSTRACT FROM AUTHOR]

The fucoid Phyllospora comosa has sparked interest from the industry as a potential commercial aquaculture species. However, information on the feasibility of culturing this species, including maximising spawning and fertilisation, remains limited. This study aimed to identify optimal conditions for spawning and early development of P. comosa under laboratory conditions. We tested spawning and germination success across lunar phase (new moon vs full moon), temperature (15 °C, 18 °C, 21 °C), light (35 μmol photons m−2 s−1 vs 0 μmol photons m−2 s−1) and exposure (desiccated vs submerged). Lunar cycles were compared over three consecutive months. Fifty fertile P. comosa male and female thalli were collected from Port Fairy, Victoria, Australia, every 2 weeks to coincide with full and new moon phases from February to April 2017. Spawning of eggs and sperm was achieved in all treatment combinations. However, there was no consistent effect of lunar phase, light, temperature or exposure, with high temporal variability amongst treatment groups. Percentage germination after 24 h in static culture varied between 35 and 90%, and overall embryo mortality was high (> 65%) after 7 days, but did not differ amongst spawning cue treatments. The high mortality observed at day 7 did not appear to be linked to insufficient egg or sperm densities nor excess sperm (polyspermy). Overall results indicate flexibility in spawning conditions which is advantageous for integration into aquaculture. [ABSTRACT FROM AUTHOR]

This study aimed to determine the nutritional composition, perceived quality and palatability of nine Australian seaweeds (wild-harvested species not yet exploited for human consumption; Laurencia filiformis, Codium galeatum, Cystophora polycystidea, Cystophora torulosa, Phyllotricha decipiens, Durvillaea potatorum, Hormosira banksii, Phyllospora comosa, Ecklonia radiata), and compare them to four of the commonest commercially available species (Pyropia tenera, Sargassum fusiforme, Saccharina angustata, Undaria pinnatifida). Nutritional value varied amongst species and inconsistently with time. Four Australian species had higher total lipids than all commercial products in this study and amongst the highest values reported in the literature for seaweeds. Moreover, nine out of 13 species had an omega-6 and omega-3 fatty acid ratio favourable for human health (≤ ~ 1). Eicosapentaenoic acid (EPA) was present in higher concentrations than docosahexaenoic acid (DHA) in all species. Highest DHA concentrations were found in Australian species, whilst EPA was very much higher in Pyropia tenera (nori) than all other species. Crude-fibre and protein contents were high for most Australian and commercially available species on a dry weight basis. A subset of Australian and commercially available seaweeds was prepared and cooked as soup or salad for sensorial (organoleptic) evaluation. There were no significant differences in consumer acceptance of any seaweeds when prepared in the soup, but acceptance of the salad dishes differed significantly, influenced primarily by a preferred texture of commercial hijiki (S. fusiforme) over the Australian species. This study identifies specific Australian seaweeds that may be viable as commercial foods. Regular consumption of 10 g (dwt) of a mixture of the seaweeds tested in this study may improve human health by contributing health-promoting fatty acids, fibre and protein to an omnivorous diet, with higher levels of consumption required for vegetarians and vegans to meet daily requirements of favourable fatty acids and protein from non-animal sources. However, further research must also examine potentially toxic effects of regularly consuming seaweeds in these quantities. [ABSTRACT FROM AUTHOR]

Stable isotope analysis (SIA) can be a useful tool for tracking the long-distance movements of migratory taxa. However, local-scale sources of isotopic variation, such as differences in habitat use or foraging patterns, may complicate these efforts. Few studies have evaluated the implications of local-scale foraging specializations for broad-scale isotope-based tracking. Here, we use > 300 h of animal-borne video footage from green turtles (Chelonia mydas) paired with SIA of multiple tissues, as well as fine-scale Fastloc-GPS satellite tracking, to show that dietary specialization at a single foraging location (Shark Bay, Western Australia) drives a high level of among-individual δ13C variability (δ13C range = 13.2‰). Green turtles in Shark Bay were highly omnivorous and fed selectively, with individuals specializing on different mixtures of seagrasses, macroalgae and invertebrates. Furthermore, green turtle skin δ13C and δ15N dispersion within this feeding area (total isotopic niche area = 41.6) was comparable to that from a well-studied rookery at Tortuguero, Costa Rica, where isotopic dispersion (total isotopic niche area = 44.9) is known to result from large-scale (> 1500 km) differences in foraging site selection. Thus, we provide an important reminder that two different behavioral dynamics, operating at very different spatial scales, can produce similar levels of isotopic variability. We urge an added degree of caution when interpreting isotope data for migratory species with complex foraging strategies. For green turtles specifically, a greater appreciation of trophic complexity is needed to better understand functional roles, resilience to natural and anthropogenic disturbances, and to improve management strategies. [ABSTRACT FROM AUTHOR]

Global demand for seaweed has increased dramatically over recent decades and the potential for seaweed aquaculture to address issues around food security and climate-change mitigation are being recognised. Australia is a global hotspot for seaweed biodiversity with a rich, diverse Indigenous history dating back 65,000 years, including an extensive traditional knowledge of Australian natural resources. In our present review of archival literature, we explored the contemporary and historical uses and cultural significance of seaweeds to Indigenous Australians. We found records of seaweed use by Indigenous Saltwater Australians (Australian Aboriginal peoples from coastal areas across the nation who are the Traditional Owners/Guardians and custodians of the lands and waters characterised by saltwater environment) for a variety of purposes including cultural activities, ceremonial activities, medicinal uses, clothing, cultural history, food, fishing, shelter and domestic uses. Species-specific records were rarely recorded (and/or accurately translated) in the archival literature, with the exception of the use of the fucoid bull kelp, Durvillaea potatorum, which was prevalent. Our research is a step forward in the important task of recovering and conserving Indigenous Australian knowledge and customary traditions surrounding coastal resource use. Unlocking this knowledge creates opportunities for the continuance and revitalization of traditional customary practises that may enable innovative Indigenous business activities and product creation, based around food, sustainable natural-fibre technologies and health. Such research also has the potential to enhance a developing Australian seaweed industry by guiding species selection, preparation, use and sustainable resource management. We recommend our findings are used to inform the direction and locations of further research conducted in conjunction with Indigenous coastal communities in Australia’s temperate regions, to explore in more detail the Indigenous Australian’s historical heritage associated with coastal seaweed resources and their uses. [ABSTRACT FROM AUTHOR]

Seaweed aquaculture beds (SABs) that support the production of seaweed and their diverse products, cover extensive coastal areas, especially in the Asian-Pacific region, and provide many ecosystem services such as nutrient removal and CO assimilation. The use of SABs in potential carbon dioxide (CO) mitigation efforts has been proposed with commercial seaweed production in China, India, Indonesia, Japan, Malaysia, Philippines, Republic of Korea, Thailand, and Vietnam, and is at a nascent stage in Australia and New Zealand. We attempted to consider the total annual potential of SABs to drawdown and fix anthropogenic CO. In the last decade, seaweed production has increased tremendously in the Asian-Pacific region. In 2014, the total annual production of Asian-Pacific SABs surpassed 2.61 × 10 t dw. Total carbon accumulated annually was more than 0.78 × 10 t y, equivalent to over 2.87 × 10 t CO y. By increasing the area available for SABs, biomass production, carbon accumulation, and CO drawdown can be enhanced. The conversion of biomass to biofuel can reduce the use of fossil fuels and provide additional mitigation of CO emissions. Contributions of seaweeds as carbon donors to other ecosystems could be significant in global carbon sequestration. The ongoing development of SABs would not only ensure that Asian-Pacific countries will remain leaders in the global seaweed industry but may also provide an added dimension of helping to mitigate the problem of excessive CO emissions. [ABSTRACT FROM AUTHOR]

The Australasian fucoid, Hormosira banksii, commonly known as 'Neptune's necklace' or 'bubbleweed' is regarded as an autogenic ecosystem engineer with no functional equivalents. Population declines resulting from climate change and other anthropogenic disturbances pose significant threats to intertidal biodiversity. For effective conservation strategies, patterns of gene flow and population genetic structure across the species distribution need to be clearly understood. We developed a suite of 15 polymorphic microsatellite markers using next generation sequencing of 53-55 individuals from two sites (south-western Victoria and central New South Wales, Australia) and a replicated spatially hierarchical sampling design. We observed low to moderate genetic variation across most loci (mean number of alleles per locus =3.26; mean expected heterozygosity =0.38) with no evidence of individual loci deviating significantly from Hardy-Weinberg equilibrium. Marker independence was confirmed with tests for linkage disequilibrium, and analyses indicated no evidence of null alleles across loci. Independent spatial autocorrelation analyses were performed for each site using multilocus genotypes and different relatedness measures. Both analyses indicated no significant patterns between relatedness and geographic distance, complemented by non-significant Hardy-Weinberg estimates ( P < 0.05), suggesting that individuals from each site represent a randomly mating, outcrossing population. A preliminary investigation of population structure indicates that gene flow among sites is limited ( F = 0.49), however more comprehensive sampling is needed to determine the extent of population structure across the species range (>10,000 km). The genetic markers described provide a valuable resource for future population genetic assessments that will help guide conservation planning for H. banksii and the associated intertidal communities. [ABSTRACT FROM AUTHOR]

This study examined the effects of a guild of micrograzing harpacticoid copepods (dominated by two species of Paradactylopodia sp. nov. and one species of Scutellidium sp. nov.) and a mesograzing periwinkle, Afrolittorina praetermissa, on the early recruitment of intertidal macroalgae on a wave-exposed, rocky shore. This is the first study, to our knowledge, to examine the effects of micrograzers (<500 μm) on intertidal macroalgal recruitment. Data showed that microscopic harpacticoid copepods altered the assemblages and reduced the densities of several macroalgal taxa, while A. praetermissa changed the assemblages and reduced both the density and number of macroalgal taxa. Recruitment of encrusting coralline algae was actually higher in copepod inclusions than exclusions, suggesting that copepods may be beneficial to the recruitment of this algal group. These results contribute to the understanding of grazing as a factor causing high mortality of algal recruits, but also highlight the need for more studies that examine the effects of micro- and mesograzers on the distribution and abundance of macroalgae. [ABSTRACT FROM AUTHOR]

Children’s literature about the ocean is a valuable learning tool for increasing ocean literacy in formal education. This instruction is, nonetheless, reliant on teachers’ capacity to explore, appreciate and understand the different ways in which elements of picture books convey ocean concepts. As researchers who work collaboratively in marine science education and children’s literature, we analysed a targeted sample of picture books about a largely unknown temperate reef system on the southern coastline of Australia, the Great Southern Reef. Our exploration of these picture books' verbal and visual strategies showed how they can be used as model examples of scientifically accurate educational resources to deliver ocean concepts, increase awareness of a local marine environment, and promote positive attitudes towards science. The portrayal of scientists, particularly female scientists in these texts can also expand children’s perceptions and beliefs about who scientists are and how they work, and ultimately impact young people’s career choices. We argue that the analysis modelled in this article can be adapted to different selections of ocean-themed picture books. Therefore, we provide recommendations for educators in other regions of the world choosing picture books to improve ocean education in the context of other local marine environments. [ABSTRACT FROM AUTHOR]