Plastics shed thousands of chemicals into the sea, including oleamide – an industrial lubricant that also occurs naturally. In lab aquariums, researchers tracked 31,500 hunting interactions between the common octopus (Octopus vulgaris) and crabs, snails, and clams. Oleamide shifted octopus prey preference, dulled crustaceans’ predator avoidance, and increased encounters – without boosting successful kills. The subtle disruption lasted days, hinting that plastic chemicals could reshape coastal food webs by altering how species sense, feed, and interact. By mimicking biological signals, plastic-derived oleamide may quietly rewire marine behavior.

Night lights affect two marine crustaceans differently, helping explain which species will be found in which portion of Tokyo Bay, Japan, according to a study. Artificial light at night can affect the behavior, physiology, and ecological distribution of marine species. Daiki Sato sought to explore the effects of city lights on the ecosystem of Tokyo Bay, one of the world’s most intensely illuminated coastal regions. Sato specifically focused on two closely related nocturnal isopods, Ligia furcata and Ligia laticarpa. Sato used genetic analysis, remote sensing, and Bayesian modeling, as well as behavioral experiments on the isopods in the lab. L. laticarpa occurrence in the bay was correlated with higher nighttime light intensity, and L. furcata showed reduced activity when reared under artificial lights at night, while L. laticarpa was largely unaffected by night lights. 

Fish-eating killer whales in southern Alaska have a diverse, seasonally changing diet featuring salmon and groundfish, according to a recently published study. The types of fish consumed also differ greatly across foraging hotspots in the region.

Scientists have been observing killer whales in Prince William Sound and Kenai Fjords as part of a long-term monitoring program launched in 1984 by the North Gulf Oceanic Society. Working from May to September, researchers have gathered a total of roughly 400 remnants of prey fish and scat to develop a picture of the whales’ diets.

Historically, killer whale diet research relied on surface sampling of prey fragments, usually scales, which allowed researchers to primarily detect salmon species. Recent techniques that analyze DNA in scat have revealed the full breadth of the whales’ diets.

The summer monsoon season runs from June through September and delivers roughly 80% of the rain India receives in a year. Over the last few decades, the amount of rain has increased while the concentration of rainfall has shifted west over the continent. Now, researchers at the Indian Institute of Tropical Meteorology have found that the intensity and location of the late-season rainfall is significantly influenced by Arctic sea ice melt that occurs earlier in the summer.

Fossils that lay almost forgotten in museum collections for over 40 years have now shed light on the earliest global radiations of land-living animals adapting to life in the sea. Around 250 million years ago, what is today scorching desert in remote northwestern Australia was the shore of a shallow bay bordering a vast prehistoric ocean. A new study has uncovered evidence of a surprisingly diverse ancient marine amphibian community with unexpectedly worldwide trans-oceanic links.

Growing up, you probably changed your style based on your social influences. It turns out, such pressures affect the appearance of young clownfish (anemonefish) too. A new study from the Okinawa Institute of Science and Technology (OIST) has revealed the social influences and biological mechanisms controlling bar loss in tomato anemonefish, showing how the presence of older fish changes the speed at which young fish lose their additional white vertical stripe.

Species numbers alone do not fully capture how ecosystems are changing. In a global study led by researchers from the German Centre for Integrative Biodiversity Research (iDiv), the Martin Luther University Halle-Wittenberg (MLU), and the Friedrich Schiller University Jena, scientists analysed long-term data from nearly 15,000 marine and freshwater fish communities. They found that fish food webs have changed substantially over recent decades, even in places where the number of species (species richness) has remained stable. Published in Science Advances, the study shows consistent shifts in species composition, body size, and feeding relationships, highlighting that changes in species traits such as body size and interactions can alter ecosystem structure without obvious changes in species richness.

Pygmy sperm whales are elusive deep divers rarely seen alive. Scientists rely on stranded individuals, especially along the southeastern U.S., to study them. Researchers analyzed more than 20 years of stranding data and identified three previously unknown Helicobacter genotypes in whale stomach tissue. Detected through histopathology, molecular diagnostics and DNA sequencing, the bacteria were linked to ulcers and inflammation, expanding knowledge of this little-known species and ocean microbes.

The widespread presence of microplastics (MPs) in aquatic ecosystems has negative impacts on human and marine life. However, the traditional MP detection methods are time-consuming and limited by detection thresholds. Now, researchers have revealed that electrochemical sensors based on metal oxide electrodes are a suitable alternative for MP detection. They highlight that metal oxides offer superior properties such as high surface area, tunable conductivity, and chemical stability, making them highly sensitive, affordable, and applicable in real-time.