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.

Linking oceanic food webs to coastal production and growth rates of Pacific salmon (Oncorhynchus spp.), using models on three scales

Abstract: Three independent modeling methods—a nutrient-phytoplankton–zooplankton (NPZ) model (NEMURO), a food web model (Ecopath/Ecosim), and a bioenergetics model for pink salmon (Oncorhynchus gorbuscha)—were linked to examine the relationship between seasonal zooplankton dynamics and annual food web productive potential for Pacific salmon feeding and growing in the Alaskan subarctic gyre ecosystem. The linked approach shows the importance of seasonal and ontogenetic prey switching for zooplanktivorous pink salmon, and illustrates the critical role played by lipid-rich forage species, especially the gonatid squid Berryteuthis anonychus, in connecting zooplankton to upper trophic level production in the subarctic North Pacific. The results highlight the need to uncover natural mechanisms responsible for accelerated late winter and early spring growth of salmon, especially with respect to climate change and zooplankton bloom timing. Our results indicate that the best match between modeled and observed high-seas pink salmon growth requires the inclusion of two factors into bioenergetics models: (1) decreasing energetic foraging costs for salmon as zooplankton are concentrated by the spring shallowing of pelagic mixed-layer depth and (2) the ontogenetic switch of salmon diets from zooplankton to squid. Finally, we varied the timing and input levels of coastal salmon production to examine effects of density-dependent coastal processes on ocean feeding; coastal processes that place relatively minor limitations on salmon growth may delay the seasonal timing of ontogenetic diet shifts and thus have a magnified effect on overall salmon growth rates.

Quantifying effects of abiotic and biotic drivers on community dynamics with multivariate autoregressive (MAR) models

Abstract: Long-term ecological data sets present opportunities for identifying drivers of community dynamics and quantifying their effects through time series analysis. Multivariate autoregressive (MAR) models are well known in many other disciplines, such as econometrics, but widespread adoption of MAR methods in ecology and natural resource management has been much slower despite some widely cited ecological examples. Here we review previous ecological applications of MAR models and highlight their ability to identify abiotic and biotic drivers of population dynamics, as well as community-level stability metrics, from long-term empirical observations. Thus far, MAR models have been used mainly with data from freshwater plankton communities; we examine the obstacles that may be hindering adoption in other systems and suggest practical modifications that will improve MAR models for broader application. Many of these modifications are already well known in other fields in which MAR models are common, although they are frequently described under different names. In an effort to make MAR models more accessible to ecologists, we include a worked example using recently developed R packages (MAR1 and MARSS), freely available and open-access software.

Disentangling the effects of climate, abundance, and size on the distribution of marine fish: an example based on four stocks from the Northeast US shelf

Abstract: Richard J. Bell1*, David E. Richardson1, Jonathan A. Hare1, Patrick D. Lynch2, and Paula S. Fratantoni3 Northeast Fisheries Science Center, National Marine Fisheries Service, Narragansett, RI 02882, USA Office of Science and Technology, National Marine Fisheries Service, Silver Spring, MD 20910, USA Northeast Fisheries Science Center, National Marine Fisheries Service, Woods Hole, MA 02543, USA *Corresponding author: tel: +001 401 782 3368; fax: +001 401 782 3201; e-mail: rich.bell@noaa.gov

The Cost of Sea Turtle Preservation: The Case of Hawaii's Pelagic Longliners

Abstract: The Cost of Sea Turtle Preservation: The Case of Hawaii's Pelagic Longliners Author(s): Rita Curtis and Robert L. Hicks Reviewed work(s): Source: American Journal of Agricultural Economics, Vol. 82, No. 5, Proceedings Issue (Dec., 2000), pp. 1191-1197 Published by: Oxford University Press on behalf of the Agricultural & Applied Economics Association Stable URL: http://www.jstor.org/stable/1244249 . Accessed: 23/01/2012 17:27

Transport through Unimak Pass, Alaska

Abstract: We examined inflow through Unimak Pass (<200 m deep), which is the only major connection between the shelves of the North Pacific Ocean and the eastern Bering Sea. Geostrophic transport was generally northward from the Gulf of Alaska into the Bering Sea. The flow through the pass appeared to be modulated by the seasonal cycle of freshwater discharge. On shorter time scales, transport also was affected by semi-daily variations in tidal mixing. This effect was significant and not anticipated. Near-bottom currents, measured from moorings, were maximum during winter, and significantly correlated (r=0.7) with the alongshore winds. Although the flow through Unimak Pass transported some nutrients from the North Pacific Ocean, the Gulf of Alaska shelf is not the major source of nutrients to the Bering Sea shelf.