The cryptic species complex, Eurytemora affinis is an important component of the mesozooplankton of estuarine transition zones (ETZs). In the St Lawrence ETZ, two clades, the Atlantic and the North-Atlantic clades co-occur. However, their distribution along environmental gradients is spatially segregated, potentially because of differential habitat exploitation. In this study, we tested two hy…

Knowledge of copepod in situ diet is critical for accurate assessment of trophic linkages and transfer efficiencies of the marine food web but is limited due to technical challenges. Here we report, using a recently developed eukaryote-universal copepod-excluding ectobiotic ciliate-blocking protocol, to investigate the natural diets of the copepods Temora turbinata, Subeucalanus subcrassus and …

Large planktivores require high-density prey patches to make feeding energetically viable. This is a major challenge for species living in tropical and subtropical seas, such as whale sharks Rhincodon typus. Here, we characterize zooplankton biomass, size structure and taxonomic composition from whale shark feeding events and background samples at Mafia Island, Tanzania. The majority of whale s…

The 2003 Bam, Iran, earthquake (Mw = 6.6) was recorded by the BAM accelerometer station. Since the causative fault was located just below the city, the accelerometer recorded the main shock, a foreshock and several local aftershocks. To study the scenario of rupturing, we simulated all components of the observed main shock waveform via the empirical Green’s function method. 28 selected afters…

In presence of large wavelength-scale shear-velocity variations in the Earth, acoustic waveform inversion may not be sufficient even when inverting long-offset data to retrieve the long-to-intermediate wavelengths of the compressional velocity. An acoustic modelling does not always correctly represent the compressional/primary waves when tuning effects and energy conversion between compression…

Protistan grazers and viruses are major agents of mortality in marine microbial communities with substantially different implications for food-web dynamics, carbon cycling and diversity maintenance.While grazers and viruses are typically studied independently, their impacts on microbial communities may be complicated by direct and indirect interactions of their mortality effects. Using a modif…

Nitrogen and iron largely determine phytoplankton production in the ocean, yet there are few direct incubation studies on nutrient limitation of phytoplankton in the western tropical North Pacific Ocean. Here, we assessed the effects of N and Fe amendments on both photosynthesis and biomass of phytoplankton (including final chlorophyll a biomass and taxonomic composition) in that region. Overal…

Aquatic ecosystems experience large natural variation in elemental composition of carbon (C), nitrogen (N) and phosphorus (P), which is further enhanced by human activities. Primary producers typically reflect the nutrient ratios of their resource, whose stoichiometric composition can vary widely in conformity to environmental conditions. In contrast, C to nutrient ratios in consumers are large…

Local earthquake tomography is a non-linear and non-unique inverse problem that uses event arrival times to solve for the spatial distribution of elastic properties. The typical approach is to apply iterative linearization and derive a preferred solution, but such solutions are biased by a number of subjective choices: the starting model that is iteratively adjusted, the degree of regularizatio…

Cyanobacteria are the primary taxa responsible for freshwater harmful algal blooms (HABs), with several genera capable of producing potent intracellular toxins and off-flavor compounds. There is considerable growing interest in methods to rapidly quantify cyanobacteria in water samples. Past studies have demonstrated poor correlations between phycocyanin in vivo fluorescence and cyanobacterial …