National Marine Fisheries Service

About: National Marine Fisheries Service is a government organization based out in Silver Spring, Maryland, United States. It is known for research contribution in the topics: Population & Fisheries management. The organization has 3949 authors who have published 7053 publications receiving 305073 citations. The organization is also known as: NOAA Fisheries & NOAA National Marine Fisheries Service.

Turtles on the edge: movement of loggerhead turtles (Caretta caretta) along oceanic fronts, spanning longline fishing grounds in the central North Pacific, 1997–1998

Abstract: Nine juvenile loggerhead sea turtles tracked during 1997 and 1998 in the central North Pacific by satellite telemetry all travelled westward, against prevailing currents, along two convergent fronts identified by satellite remotely sensed data on sea surface temperature (SST), chlorophyll and geostrophic currents. These fronts are characterized by gradients in sea surface height that produce an eastward geostrophic current, with gradients in surface chlorophyll and SST. Six of the turtles were associated with a front characterized by 17∞C SST, surface chlorophyll of about 0.2 mg m ‐3 , and eastward geostrophic current of about 4 cm s ‐1 , while the other three turtles were associated with a front with 20∞C SST, surface chlorophyll of about 0.1 mg m ‐3 , and eastward geostrophic flow of about 7 cm s ‐1 . These results appear to explain why incidental catch rates of loggerheads in the Hawaii longline fishery are highest when gear is set at 17∞C and 20∞C, SST. Further, from the seasonal distribution of longline effort relative to these fronts, it appears that the surface longline fishing ground lies largely between these two fronts during the first quarter and well to the south of the 17∞C front, but including the 20∞C front, in the second quarter. These findings suggest seasonal or area closures of the longline fishery that could be tested to reduce incidental catches of loggerheads. Finally, these results illustrate

Dispelling Some Myths about Hatcheries

Abstract: Contributing to the controversies that have surrounded fish hatcheries in recent years are a number of misconceptions or myths about hatcheries and their effects on natural populations. These myths impede productive dialogue among those with differing views about hatcheries. Most of the myths include a measure of truth, which makes it difficult to recognize the elements that are not true. Consideration of these myths leads to the following conclusions: (1) Hatcheries are intrinsically neither good nor bad—their value can be determined only in the context of clearly defined goals; (2) genetic changes in cultured populations can be reduced but not eliminated entirely; (3) empirical evidence exists of many adverse effects of hatcheries, but some risks have been overstated; and (4) monitoring and evaluation programs are important but should not be used as a substitute for developing risk-averse hatchery programs in the first place. A key step in resolving some of the controversies will be moving towa...

Copepod hatching success in marine ecosystems with high diatom concentrations

Abstract: Diatoms dominate spring bloom phytoplankton assemblages in temperate waters and coastal upwelling regions of the global ocean. Copepods usually dominate the zooplankton in these regions and are the prey of many larval fish species. Recent laboratory studies suggest that diatoms may have a deleterious effect on the success of copepod egg hatching. These findings challenge the classical view of marine food-web energy flow from diatoms to fish by means of copepods. Egg mortality is an important factor in copepod population dynamics, thus, if diatoms have a deleterious in situ effect, paradoxically, high diatom abundance could limit secondary production. Therefore, the current understanding of energy transfer from primary production to fisheries in some of the most productive and economically important marine ecosystems may be seriously flawed. Here we present in situ estimates of copepod egg hatching success from twelve globally distributed areas, where diatoms dominate the phytoplankton assemblage. We did not observe a negative relationship between copepod egg hatching success and either diatom biomass or dominance in the microplankton in any of these regions. The classical model for diatom-dominated system remains valid.

Climate Change and Marine Fish Distributions: Forecasting from Historical Analogy

Abstract: Analyses of 36 fish and squid species sampled in standardized bottom-trawl surveys of the northwest Atlantic Ocean (1967–present) revealed a continuum of distributional responses associated with seasonal and annual variations in water temperature. Mean and maximum latitude of occurrence of the species were regressed against average surface- and bottom-water temperatures and indices of relative abundance from spring and autumn trawl surveys. Significant (P ≤ 0.05) regression models were fitted for 17 of 36 species from spring and fall survey data. Variations in water temperature were significant in explaining changes in mean latitude of occurrence for 12 of 36 species in both seasons. Maximum latitude distribution responses to interannual differences in water temperatures occurred for pelagic species, including Atlantic mackerel Scomber scombrus and Atlantic herring Clupea harengus. Weighted mean catches of these species shifted poleward by 0.5–0.8 degree of latitude for each 1°C increase in avera...