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The global marine fish catch is approaching its upper limit. The number of overfished populations, as well as the indirect effects of fisheries on marine ecosystems, indicate that management has failed to achieve a principal goal, sustainability. This failure is primarily due to continually increasing harvest rates in response to incessant sociopolitical pressure for greater harvests and the intrinsic uncertainty in predicting the harvest that will cause population collapse. A more holistic approach incorporating interspecific interactions and physical environmental influences would contribute to greater sustainability by reducing the uncertainty in predictions. However, transforming the management process to reduce the influence of pressure for greater harvest holds more immediate promise

Changes in the invertebrate fauna of a California rocky intertidal community between the period 1931 to 1933 and the period 1993 to 1994 indicate that species' ranges shifted northward, consistent with predictions of change associated with climate warming. Of 45 invertebrate species, the abundances of eight of nine southern species increased and the abundances of five of eight northern species decreased. No trend was evident for cosmopolitan species. Annual mean shoreline ocean temperatures at the site increased by 0.75 degrees C during the past 60 years, and mean summer maximum temperatures from 1983 to 1993 were 2.2 degrees C warmer than for the period 1921 to 1931

In oceanic, coastal, and estuarine environments, an average of 25 to 41 percent of the dissolved inorganic nitrogen (NH4+ and NO3-) taken up by phytoplankton is released as dissolved organic nitrogen (DON). Release rates for DON in oceanic systems range from 4 to 26 nanogram-atoms of nitrogen per liter per hour. Failure to account for the production of DON during nitrogen-15 uptake experiments results in an underestimate of gross nitrogen uptake rates and thus an underestimate of new and regenerated production. In these studies, traditional nitrogen-15 techniques were found to underestimate new and regenerated production by up to 74 and 50 percent, respectively. Total DON turnover times, estimated from DON release resulting from both NH4+ and NO3(-) uptake, were 10 +/- 1, 18 +/- 14, and 4 days for oceanic, coastal, and estuarine sites, respectively

Cooperation and Engagement in the Asia-Pacific Region provides valuable insight into a region that encompasses many important maritime regions, and harbors promising opportunities for maritime cooperation and engagement.

Otolith microchemical analyses of the strontium (Sr) and calcium (Ca) concentrations in the eels Anguilla japonica and A. anguilla caught in Tokyo Bay were undertaken to reconstruct the eels' migratory histories. A. japonica in the yellow stage (immature stage) were caught in a bay without any adjacent rivers or streams. A. anguilla was in the silver stage (early maturing stage), and the eel was confirmed to have just begun spawning migration to the open ocean from Tokyo Bay based on the otolith Sr:Ca ratios, which showed a typical catadromous life history with low Sr:Ca ratio values throughout the eel's life after recruitment. The mean Sr:Ca ratios in A. japonica from the elver mark to the otolith edge indicated the eels belonged to several general categories of migratory histories, including sea eels (average Sr:Ca ratio =6.0 x 10E-3) and estuarine eels (average Sr:Ca ratio 2.5 to 6.0 x 10E-3) based on the criteria reported previously in A. japonica. All eels had a certain freshwater life period, although the period was highly variable among fish. These results indicate that A. japonica has a flexible pattern of migration, with the ability to adapt to various habitats and salinities.

Los plásticos están presentes en todos los aspectos de la vida cotidiana y su producción masiva alrededor del mundo ha traído consigo un área emergente de investigación: los microplásticos, estas partículas de tamaño diminuto están causando graves efectos en el ambiente marino, a tal punto que hay una creciente preocupación por los posibles efectos sobre la biota, el equilibrio de los ecosistemas marinos y la salud humana. La presente revisión tiene por objetivo brindar una visión más integrada de la contaminación por microplásticos y sus posibles problemáticas asociadas en los ecosistemas marinos y costeros de Colombia. Teniendo en cuenta la información disponible hasta la fecha, se evidencia un aumento progresivo en el estudio de estos contaminantes principalmente en cuanto a su distribución. Sin embargo, existe escaza información del efecto que puede tener sobre la biodiversidad de los ecosistemas marinos de Colombia, por ello se hizo necesario recurrir a bibliografía internacional, en la cual se atribuyen tres problemáticas a los microplásticos: la ingestión por parte de la biota marina, proliferación de microorganismos no deseados y la biomagnificación de sustancias tóxicas, lo cual respalda que estas partículas son una amenaza evidente para los ecosistemas marinos de Colombia. Finalmente, se proponen siete áreas de actuación para el estudio de estas partículas, y algunas estrategias que permitan minimizar su efecto, haciendo énfasis en que la educación pública es una parte crítica para crear cambios a nivel social.

DDT is reductively dechlorinated to DDD and dehydrochlorinated to DDE; it has been thought that DDE is not degraded further in the environment. Laboratory experiments with DDE-containing marine sediments showed that DDE is dechlorinated to DDMU in both methanogenic and sulfidogenic microcosms and that DDD is dehydrochlorinated to DDMU three orders of magnitude more slowly. Thus, DDD does not appear to be an important precursor of the DDMU found in these sediments. These results imply that remediation decisions and risk assessments based on the recalcitrance of DDE in marine and estuarine sediments should be reevaluated

A gram-negative, motile, coccoid- and amorphous-shaped, non-pigmented chemoheterotrophic bacterium, designated strain PZ-5∨T, was isolated from sea water of Sagami Bay in Japan and subjected to a polyphasic taxonomic study. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the novel isolate could be affiliated with the class Gammaproteobacteria. Strain PZ-5∨T showed below 93.9% similarity with validly published bacteria and demonstrated the highest sequence similarity to Dasania marina KOPRI 20902∨T (93.9%). Strain PZ-5∨T formed a monophyletic group with D. marina KOPRI 20902∨T. The DNA G+C content of strain PZ-5∨T was 49.8 mol%. The major isoprenoid quinone was Q-8 and predominant cellular fatty acids were C∧15:0 ISO 2OH (19%), C∧16:1 ω7c (17.4%), C∧17:1 ω8c (16.2%), C∧11:0 3OH (7.5%), and C∧15:1 ω8c (6.5%). Based on evidence from a polyphasic taxonomical study, it was concluded that the strain should be classified as representing a new genus and species of the class Gammaproteobacteria, for which the name Oceanicoccus sagamiensis gen. nov., sp. nov., (type strain PZ-5∨T =NBRC 107125∨T =KCTC 23278∨T) is proposed.

We investigated the environmental factors providing signals for gamete release in fucoid algae, with a particular focus on the inhibitory effect of water motion. The release of gametes by Fucus distichus occurred in still water under high light and was associated with the depletion of dissolved inorganic carbon (DIC) in tide pools isolated from the ocean during daytime low tides. Diurnal patterns of gamete release that lasted for 2-3 d, as in natural populations, were found in receptacles cultured in a 12 h light: 12 h dark photoperiod under calm conditions or in a simulated tidal regime. Constant light disrupted the diurnal component of release, however, suggesting that an endogenous circadian periodicity was absent. The effects of increased [DIC] on cultured receptacles under calm conditions were similar to the inhibitory effects of high water motion; both conditions reduced release in several species from both tide pool and intertidal habitats. Bicarbonate concentration, rather than carbon dioxide, or carbonate, was shown to be the component of the DIC system most closely correlated (inversely) with gamete release in the intertidal fucoid Pelvetia compressa. The hypothesis that gamete release is triggered by DIC depletion in the unstirred boundary layer during periods of low water motion in the light was further supported by experiments with P. compressa. These showed that gamete release was not inhibited by high water motion when DIC was absent. In the same experiments, high water motion inhibited release at 2 and 20 mmol/L DIC, confirming that the sensitivity of gamete release to water motion is DIC dependent. The ability of fucoid algae to couple physiological processes (e.g., photosynthesis) with life history events (gamete release) allows external fertilization to occur under favorable hydrodynamic conditions, and may contribute greatly to reproductive success in organisms inhabiting periodically turbulent environments.