Description: Small herbivores are abundant on large marine macrophytes, but their impact on their hosts is poorly understood relativeuto large grazers such as urchins and fish. To limit the risks of predation, many marine mesograzers live within nests or burrows,upotentially causing more damage to plants than predicted from consumption alone. To test whether the growth ofularge primary producers can be affected by modification of plant structures by small herbivores, we quantified the effect ofuthe nest-building amphipod Pseudopleonexes lessoniae on blades of the giant kelp, Macrocystis pyrifera in New Zealand.uAmphipods create their nests by rolling the blade margin in close proximity to the meristem. Blades with nests were 40%ushorter than blades lacking nests and reduced in area by 55%. We examined the composition of amphipods inhabiting eachunest to assess the temporal persistence of grazer aggregations. Nests were occupied by a single female or male–female pairs, and their newly hatched offspring. Analysis of offspring size distributions suggested that offspring dispersed from the maternal nest and did not remain to breed themselves. By concentrating physical damage and feeding on valuable tissues, these results indicate that even low numbers of small herbivores can cause localized impacts on the morphology and size of fast-growing algal blades. Predicting the consequences of this damage on larger scales will require understanding the spatial and temporal distribution of amphipod nests on giant kelp.

Description: Vast quantities of plastics are accumulating in the oceans. At sea, plastics interact with marine biota often with deleterious consequences for organisms and habitats. As users of marine food resources and ecosystem services humans are also affected by marine plastic litter. Economic, social and health implications necessitate decisive action to manage this growing environmental problem at a global scale. Accordingly, legislative and technological instruments have been implemented to reduce the amounts of marine plastic debris. Promising strategies to reduce the human plastic footprint in the oceans must involve the minimization of plastic discharges into the marine environment.

Description: For many years, the pollution of the oceans with marine litter received only little attention from the public although the global plastic production has grown steadily. However, since the “discovery” of the oceanic garbage patches and microplastics the littering of the oceans has become a hot topic, which is reflected in strong recent increases in the number of publications. Despite growing research efforts many questions remain unanswered and the new wealth of information does not readily transpire to the general public, which is left unsettled. For example, it is still unclear what the overall extent of ocean pollution is, or how the enormous amounts of oceanic plastics affect marine life and ecosystems. To overcome this uncertainty and make best use of the existing knowledge, we currently develop an online portal for marine litter and microplastic pollution named LITTERBASE. As of early 2017, LITTERBASE will provide access to the current state of understanding of marine litter and microplastics to the general public and stakeholders. Published records of marine litter and microplastics and their impact on marine life will be compiled in a database. The regularly updated information will be displayed in distribution maps and other graphs in an interactive online portal. In the long run, data from citizen scientists may also be integrated into these infographs.