Therapeutic potential of seaweeds

Seaweeds in general are known to contribute to the maintenance of health through their nutritional and medicinal properties and are served in soups and salads, cooked with grains, legumes or miso-soup broth, vegetable pies, stews and even consumed dried. The medicinal properties of seaweeds or vegetables have long been known in many cultures of people particularly those living in the coastal regions who are consuming these from centuries. Traditional Chinese dietotherapy (TCD) makes good use of natural marine nutrients and food to preserve health. Koreans wrap their bodies in seaweeds to get rid of deadly body toxins and Japanese who eat large quantities of seaweeds have very low incidence of cancers. The compounds with diverse biological activities such as antioxidant, antiviral, antifungal, antineoplastic, antimicrobial etc. have been isolated from the flora in the sea. A score of these bio-medicinal compounds are in different stages of clinical trials & analysis and are the focus of this article.

Big runs of little fish: First estimates of run size and exploitation in an amphidromous postlarvae fishery

Amphidromous Postlarvae Fisheries (APFs) constitute a globally-widespread and distinctive class of fishery that is largely unknown to fisheries science. APFs harvest ocean-to-river migrating fishes at smaller sizes and younger ages than any other class of fishery. No quantitative estimates of run size and exploitation exist, which are needed to evaluate APF sustainability. Migrating amphidromous fishes are vectors of marine nutrients to estuaries and rivers, and run size quantification is needed to reveal the magnitude of this ecosystem function. We present a novel adaptation of trapezoidal area under the curve (TAUC) methods, which we apply in a Caribbean case study to yield the first simultaneous estimates of an APF run size and harvest. Run size estimates ranged 7.3–9.4 million postlarvae (926–1,184 kg), and exploitation estimates (5.8–7.0%) indicated low harvest in the Río Grande de Arecibo, Puerto Rico. Our representative run size estimates reveal that amphidromous postlarvae transport hundreds of kilograms of biomass per month to an estuary and river, the first empirical evidence that amphidromous migrations are large-magnitude material subsidies of lotic ecosystems.

Salish Sea a Key Source of Regional Marine Nutrients

A new examination of nitrogen in the coastal waters off the Pacific Northwest shows that the Salish Sea delivers a large fraction of nutrients to shelf waters.

Marine nutrient transport: anadromous fish migration linked to the freshwater amphipod Gammarus fasciatus

Migrating anadromous fish may transfer marine-derived nutrients to oligotrophic tidal fresh water. River herrings (genus Alosa Linck, 1790) are the dominant anadromous genus in Virginia, USA. This study investigates whether marine nutrients derived from spawning Alosa spp. were incorporated into benthic invertebrates by using the stable isotopes of carbon and nitrogen. Spawning Alosa spp. had higher δ13C and δ15N values (–18.5‰ and 13.9‰, respectively) than resident freshwater omnivorous fishes (–25.7‰ and 11.8‰, respectively). In a tidal stream supporting abundant spawning Alosa spp., 13C and 15N enrichment was observed in stream amphipods (Gammarus fasciatus Say, 1818) coincident with the spawning migration of Alosa spp. The δ13C value for G. fasciatus increased from –28.5‰ to –26.0‰ from early to late April then fell to –28.1‰ in early June. A similar trend was observed in mayflies (Heptageniidae). Particulate organic matter and sediments from both streams remained depleted in 13C (between –29‰ and –28‰) and 15N (between 0.5‰ and 3.0‰) during the spawning run of Alosa spp. It is estimated that between 5% and 35% of amphipod biomass may be derived from marine carbon brought to tidal fresh water by spawning Alosa spp.