No abstract

Marine debris is distributed worldwide and constitutes an increasing threat to our environment. The exponential increase of plastic debris raises numerous concerns and has led to an intensification in plastic monitoring and research. However, global spatial and temporal patterns and knowledge gaps in debris distribution, both on land and at sea, are relatively poorly understood, mainly due to a lack of comprehensive datasets. Here we critically review the quality of the available information on beach plastic debris worldwide to highlight where the most urgent actions are required, and to promote the standardization of reporting metrics and sampling methods among researchers. From a total of 174 studies evaluated, 27.0% reported marine debris densities in metrics that were not comparable. Some studies failed to report basic parameters, such as the date of the sampling (9.8%) or the size of the collected debris (19.5%). Our findings show that current research regarding beach debris requires significant improvement and standardization and would benefit from the adoption of a common reporting framework to promote consensus within the scientific community.

The lunar cycle is believed to strongly influence the vertical distribution of many oceanic taxa, with implications for the foraging behaviour of nocturnal marine predators. Most studies to date testing lunar effects on foraging have focused on predator activity at-sea, with some birds and marine mammals demonstrating contrasting behavioural patterns, depending on the lunar-phase. However, to date no study has focused on how the lunar cycle might actually affect predator-prey interactions in the upper layers of the ocean. Here, we tested whether the diet of the predominantly nocturnal pelagic predator, the Bulwer’s petrel (Bulweria bulwerii) would change throughout the lunar cycle, using molecular analysis to augment detection and taxonomic resolution of prey collected from stomach-contents. We found no evidence of dietary shifts in species composition or diversity, with Bulwer’s petrel always consuming a wide range of mesopelagic species. Other co-variables potentially affecting light availability at-sea, such as percentage of cloud cover, did not confound our results. Moreover, many of the species found are thought not to reach the sea-surface. Our findings reveal that nocturnal predators are probably more specialized than previously assumed, irrespective of ambient-light, but also reveal deficiencies in our current understanding of species vertical distribution and predation-dynamics at-sea.

Engagement in marine science has historically been the privilege of a small number of people with access to higher education, specialised equipment and research funding. Such constraints have often limited public engagement and may have slowed the uptake of ocean science into environmental policy. Recognition of this disconnect has spurred a growing movement to promote ocean literacy, defined as one’s individual understanding of how the ocean affects people and how people affect the ocean. Over the last 2 decades, this concept has gained significant traction in marine biology and environmental education circles and now plays a prominent role in the UN’s Decade of Ocean Science for Sustainable Development (2021-2030). Here, we argue that the ocean literacy agenda has largely been shaped and discussed by marine scientists and educators but needs to be expanded to a much larger constituency to be more effective, accessible and inclusive. We discuss diverse cultural settings from around the world and provide examples of indigenous, spiritual, art, ocean user and other groups that are already deeply engaged with the ocean and could provide a variety of perspectives to enrich the ocean literacy concept beyond an understanding of marine science. We suggest that such inclusiveness could remove the historic barriers that have surrounded the field, transform our collective awareness of and relationship with the ocean and help support ongoing efforts to restore marine biodiversity.