Seagrass wasting disease is a very devastating infection that darkens the blades and threatens several marine ecosystems that rely on seagrass meadows. We investigated the dynamics of leaf-associated bacteria in healthy and diseased individuals of the seagrass species Zostera muelleri and found that pronounced changes take place within these communities, even in the absence of the proposed aetiological agent Labyrinthula zosterae.

Climate change is warming the world’s oceans, and will disrupt marine populations. We have shown that in Alaska and Washington nearshore waters, the recruitment and abundance of giant Pacific octopuses fell sharply following years of higher average ocean temperatures. Visual surveys and ocean temperature data together may allow better management of octopus harvests.

Prochilodus lineatus is a migratory Neotropical fish that constitutes the principal targeted species in the fishery of the Lower Rio de la Plata Basin. P. lineatus larvae drift downstream from spawning to nursery areas, where first feeding takes place. This study experimentally investigated the morphological, physiological and behavioural changes in P. lineatus larvae under food-deprivation v. feeding conditions. The results are discussed in the context of the distribution and survival of wild larvae.

Algal diversity and their conservation value remain largely understudied, despite that environmental pressures in the rivers of arid and semiarid regions of Patagonia are a major concern. This study shows that diatoms are more diverse than was previously recognised in the Chubut River, where a high proportion of endemic elements could occur. Ecological preferences of some diatom species also suggest an enrichment of nutrients towards the lower basin and show the maximum intrusion of seawater into the estuary.

We investigated spring diatom blooms in a temperate freshwater river that is thought to predominantly include the diatom Stephanodiscus hantzschii. The results suggested the coexistence of many diatoms during spring blooms. However, Cyclotella sp. was responsible for the spring bloom attributed to S. hantzschii. The co-occurrence of similar species should be considered when implementing efforts to control spring blooms.

A novel approach, the CDOM_LH algorithm, was developed to retrieve the absorption coefficient of chromophoric dissolved organic matter (a_CDOM) in non-turbid waters, and was calibrated and validated. One implication for the MERIS satellite data, which exhibit reasonable seasonal variability over the East China Sea, is that it can be used to explore biogeochemical effects on aquatic environments.

A model to refine release densities for crustaceans targeted for stocking into estuaries or freshwaters is presented. The approach uses bioenergetic information, which can be measured readily in the laboratory, alongside estimates of primary productivity, growth and mortality, to optimise stocking density for species and ecosystems on the basis of expected trophic impact of the stocked cohorts. The model is generalised so that simulations can be made for any species or system for which parameters can be estimated or measured.

Owing to species diversity, uncertainties regarding the relationships among the different groups of Percomorpha have always been a challenge in conducting phylogenetic studies on teleosts. In this study, the genomes of 34 representative species of the 7 major taxa of Percomorpha were evaluated to solve this problem. The present study provides a new perspective and possibilities for further studies on the Percomorpha branch and other higher-order meta-taxonomic relationships of fish.