scholarly journals Time-series metabarcoding analysis of zooplankton diversity of the NW Atlantic continental shelf

2019 ◽  
Vol 76 (4) ◽  
pp. 1162-1176 ◽  
Author(s):  
Ann Bucklin ◽  
Heidi D Yeh ◽  
Jennifer M Questel ◽  
David E Richardson ◽  
Bo Reese ◽  
...  
Keyword(s):  
Time Series ◽  
Gulf Of Maine ◽  
Diversity Index ◽  
Hypervariable Region ◽  
Detailed Examination ◽  
Science Center ◽  
Ecosystem Monitoring ◽  
Fisheries Science ◽  
Ocean Ecosystem ◽  
Taxonomic Groups

Abstract Biodiversity of zooplankton is central to the functioning of ocean ecosystems, yet morphological taxonomic analysis requires teams of experts and detailed examination of many samples. Metabarcoding (DNA sequencing of short amplified regions of one or a few genes from environmental samples) is a powerful tool for analysis of the composition and diversity of natural communities. The 18S rRNA V9 hypervariable region was sequenced for 26 zooplankton samples collected from the Gulf of Maine, Georges Bank, and Mid-Atlantic Bight during ecosystem monitoring surveys by the U.S. Northeast Fisheries Science Center during 2002–2012. A total of 7 648 033 sequences and 22 072 operational taxonomic units (OTUs) were identified and classified into 28 taxonomic groups of plankton. Comparative analysis of molecular (V9 sequence numbers) and morphological (abundance counts) focused on seven taxonomic groups and revealed similar patterns of variation among years and regions. Sequence numbers and abundance counts showed positive correlation for all groups, with significant correlations (p < 0.05) for Calanoida, Gastropoda, and Chaetognatha. Shannon diversity index values calculated using sequence numbers and abundance counts showed highly significant correlation (r = 0.625; p < 0.001) across all regions during 2002–2012. This study demonstrates the potential of metabarcoding for time-series analysis of zooplankton biodiversity, ocean ecosystem assessment, and fisheries management.

scholarly journals Age-specific differences in the seasonal spatial distribution of butterfish (Peprilus triacanthus)

2016 ◽  
Vol 74 (1) ◽  
pp. 170-179 ◽  
Author(s):  
Charles F. Adams
Keyword(s):  
Time Series ◽  
Spatial Distribution ◽  
Reference Points ◽  
Trawl Survey ◽  
Spatial Equilibrium ◽  
Science Center ◽  
Fisheries Science ◽  
Specific Analysis ◽  
Stock Assessments ◽  
Seasonal Analysis

The spatial distribution of butterfish (Peprilus triacanthus) in the Northwest Atlantic Ocean was investigated using a suite of spatial indicators based on Northeast Fisheries Science Center spring and fall bottom trawl survey data, 1982–2013. In the spring, ages 2 and 3 were found farther northeast and deeper than age 1 butterfish, while in the fall, age 3 butterfish were found farther northeast and deeper than ages 0 and 1. There was no significant northward movement of butterfish in spring or fall over the course of either time-series. However, there was a significant increase in the area occupied by ages 1–3 in the spring that was correlated with surface temperature. This illustrates that responses to climate change may be manifested as range expansions, rather than poleward movement of the centre of gravity (i.e. bivariate weighted mean location of the population). Two changes were observed over the course of the fall time series, both for ages 1 and 2: increased spatial dispersion; and a decrease in depth. The former result would have been masked, while the latter would have been erroneously generalized to all age classes, if an age-specific analysis had not been done. This study demonstrates the importance of an age-based and seasonal analysis. It is also shown how a spatial distribution analyses can inform stock assessments by providing insights into diverging survey indices and availability to surveys in general. Similarly, spatial distribution analyses can be used to verify the spatial equilibrium assumption for the calculation of biological reference points.

Possible climate-induced environmental impacts on parasite-infection rates of northern shrimp Pandalus borealis eggs in the Gulf of Maine

2020 ◽  
Vol 140 ◽  
pp. 109-118
Author(s):  
HY Chang ◽  
R Klose ◽  
Y Chen
Keyword(s):  
New England ◽  
Environmental Changes ◽  
Gulf Of Maine ◽  
Infection Rates ◽  
Science Center ◽  
Infected Female ◽  
Pandalus Borealis ◽  
Fisheries Science ◽  
Female Body Size ◽  
Northern Shrimp

The Gulf of Maine northern shrimp Pandalus borealis population once supported a significant commercial winter fishery for the New England states. However, the fishery has been on moratorium since 2014 due to consecutive recruitment failures. The issue of parasite-infected eggs, so-called ‘white eggs,’ has long been identified for the Gulf of Maine northern shrimp, which makes shrimp eggs nonviable and subsequently hampers the recruitment potential. Furthermore, the proportion of infected females was observed to increase with water temperature. As Gulf of Maine temperatures have been increasing for decades, it is important to re-visit issues related to white eggs to evaluate possible impacts of climate-induced environmental changes on the white egg infection rates. We used biological samples collected by the Northeast Fisheries Science Center in 2012-2016 to evaluate the probability that a female shrimp was infected (Pinf) and the proportion of white eggs in an infected female shrimp (pwe). Although Pinf was high, with an average of 73.81% over the Gulf of Maine, pwe was mostly <5%. The variation in both Pinf and pwe examined in this study was not well explained by environmental factors or female body size. However, the average rates of both Pinf and pwe observed in this study were higher than those observed in the 1960s when the bottom temperatures were cooler. The results can be used to account for egg mortality and provide information on potential impacts of possible climate-induced variability on shrimp population dynamics.

Satellite Detection of Ghost Nets and Plastic Debris in Pacific Atolls

2021 ◽  
Author(s):  
Yangrong Ling ◽  
Lauren Biermann ◽  
Mark Manuel ◽  
Ellen Ramirez ◽  
Austin Coates ◽  
...  
Keyword(s):  
Satellite Imagery ◽  
Pacific Islands ◽  
Science Center ◽  
Spectral Angle Mapper ◽  
Plastic Debris ◽  
Fisheries Science ◽  
The Pacific ◽  
The Pacific Ocean ◽  
Derelict Fishing Gear ◽  
Satellite Analysis

&lt;p&gt;&lt;span&gt;Since 2014, the NOAA Satellite Analysis Branch has used high resolution optical satellite imagery in an effort to detect ghost nets (derelict fishing gear) and other large plastic debris in the Pacific Ocean and its atolls in support of clean-up efforts (by the NOAA Pacific Islands Fisheries Science Center, Ocean Voyages Institute, etc.). Until recently, reliable detection has proven challenging. With the application of Worldview imagery matched to &lt;em&gt;in situ&lt;/em&gt; information on known net locations, we have been able to extract spectral signatures of floating plastics and use these to detect and identify other instances of plastic debris. Using ENVI&amp;#8217;s Spectral Angle Mapper (SAM) target detection method, a number of likely locations of nets/plastics in the Pearl and Hermes atoll in the Northwestern Hawaiian Islands (NWHI) were highlighted. The resulting locations of the 41 debris detections were strikingly similar to the distributions along the coast reported in surveys, and are consistent with those that would be expected due to the seasonal ocean currents. This satellite imagery analysis procedure will be repeated shortly before the next NWHI clean-up effort, which will better enable us to support the removal of ghost nets and other marine plastics, and also assess the accuracy and rapid reproducibility of the technique.&lt;/span&gt;&lt;/p&gt;

scholarly journals Multi-Decadal Trends and Variability in Temperature and Salinity in the Mid-Atlantic Bight, Georges Bank, and Gulf of Maine

2018 ◽  
Vol 76 (5) ◽  
pp. 163-215 ◽  
Author(s):  
Elizabeth J. Wallace ◽  
Lev B. Looney ◽  
Donglai Gong
Keyword(s):  
River Discharge ◽  
Gulf Of Maine ◽  
Winter Season ◽  
Hudson River ◽  
The Other ◽  
Georges Bank ◽  
Spring Season ◽  
Science Center ◽  
Other Hand ◽  
Decadal Scale

Increasing attention is being placed on the regional impact of climate change. This study focuses on the decadal scale variabilities of temperature and salinity in the Mid-Atlantic Bight (MAB), Georges Bank (GB), and Gulf of Maine (GOM) from 1977 to 2016 using hydrographic survey data from the National Oceanic and Atmospheric Administration (NOAA) Northeast Fisheries Science Center. The MAB (as defined by the shelf regions from Cape Hatteras to Cape Cod) experienced warming rates of 0.57 °C per decade during the Winter/Spring season (Jan–Apr) and 0.47 °C per decade during the Fall/Winter season (Sep–Dec). The GOM and GB, on the other hand, warmed at approximately half the rate of the MAB over the same time span (1977–2016). We found that rates of warming vary on decadal time scales. From 1977 to 1999, significant temperature increases (> 0.6 °C/decade) were found in the southern regions of the MAB during the Winter/Spring season. During the same period, significant freshening (stronger than– 0.2/decade) was found in GB and the northern regions of the MAB during the Winter/Spring and Summer seasons. From 1999 to 2016, on the other hand, we found no significant trends in temperature and few significant trends in salinity with the exceptions of some northern MAB regions showing significant salting. Interannual variability in shelf salinity can in part be attributed to river discharge variability in the Hudson River and Chesapeake Bay. However, decadal scale change in shelf salinity cannot be attributed to changes in river discharge as there were no significant decadal scale changes in river outflow. Variability in along-shelf freshwater transport and saline intrusions from offshore were the likely drivers of long-term changes in MAB shelf-salinity.

Catch and Release in Marine Recreational Fisheries

2002 ◽  
Keyword(s):  
Commercial Fishing ◽  
Migratory Species ◽  
Science Center ◽  
Fisheries Science ◽  
Atlantic Bluefin Tuna ◽  
Tag Retention ◽  
Catch And Release ◽  
Istiophorus Platypterus ◽  
Makaira Nigricans ◽  
Fishing Vessels

<em>Abstract.</em>—The Cooperative Tagging Center (CTC) of the National Marine Fisheries Service’s Southeast Fisheries Science Center operates one of the largest and oldest fish tagging programs of its type in the world. Since 1954, more than 35,000 recreational and commercial fishing constituents have voluntarily participated in the CTC, and this has resulted in tagging more than 245,000 fish of 123 species. Although some tagging activities have been conducted by scientists, most of the tag release and recovery activities were achieved by recreational and commercial fishery constituents. Five large highly migratory species have historically represented the Program’s primary target species, including Atlantic bluefin tuna <em> Thunnus thynnus</em>, blue marlin <em> Makaira nigricans</em>, white marlin <em> Tetrapturus albidus</em>, sailfish <em> Istiophorus platypterus</em>, and broadbill swordfish <em> Xiphias gladius</em>. Tagging equipment and procedures for catching, tagging, and resuscitation of species too large to be brought aboard fishing vessels have evolved and improved considerably over the years. This paper presents a review of the development of the most efficient tagging, handling, and dehooking techniques used on a variety of large, highly migratory species in the CTC. In addition, the results of a comparative tag retention study on billfish are presented, comparing stainless steel dart tags used for nearly 30 years with a hydroscopic nylon double-barb dart tag, recently developed in conjunction with The Billfish Foundation. Recommendations are made on the best techniques, procedures, and equipment for in-water tagging of large, highly migratory species.

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