Seasonal transport variations in the straits connecting Prince William Sound to the Gulf of Alaska

2013 ◽  
Vol 63 ◽  
pp. S63-S78 ◽  
Author(s):  
Mark J. Halverson ◽  
Claude Bélanger ◽  
Shelton M. Gay
Keyword(s):  
Gulf Of Alaska ◽  
Prince William Sound

scholarly journals An empirical Bayesian approach to incorporate directional movement information from a forage fish into the Arnason-Schwarz mark-recapture model

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Mary A. Bishop ◽  
Jordan W. Bernard
Keyword(s):  
Bayesian Approach ◽  
Gulf Of Alaska ◽  
Forage Fish ◽  
Pacific Herring ◽  
Prince William Sound ◽  
Modeling Framework ◽  
Empirical Bayesian ◽  
Directional Information ◽  
Directional Movement ◽  
Empirical Bayesian Approach

Abstract Background Over the past two decades, various species of forage fish have been successfully implanted with miniaturized acoustic transmitters and subsequently monitored using stationary acoustic receivers. When acoustic receivers are configured in an array, information related to fish direction can potentially be determined, depending upon the number and relative orientation of the acoustic receivers. However, it can be difficult to incorporate directional information into frequentist mark-recapture methods. Here we show how an empirical Bayesian approach can be used to develop a model that incorporates directional movement information into the Arnason-Schwarz modeling framework to describe survival and migration patterns of a Pacific herring (Clupea pallasii) population in coastal Alaska, USA. Methods We acoustic-tagged 326 adult Pacific herring during April 2017 and 2018 while on their spawning grounds in Prince William Sound Alaska, USA. To monitor their movements, stationary acoustic receivers were deployed at strategic locations throughout the Sound. Receivers located at the major entrances to the Gulf of Alaska were arranged in parallel arrays to determine the directional movements of the fish. Informative priors were used to incorporate the directional information recorded at the entrance arrays into the model. Results A seasonal migratory pattern was found at one of Prince William Sound’s major entrances to the Gulf of Alaska. At this entrance, fish tended to enter the Gulf of Alaska during spring and summer after spawning and return to Prince William Sound during the fall and winter. Fish mortality was higher during spring and summer than fall and winter in both Prince William Sound and the Gulf of Alaska. Conclusions An empirical Bayesian modeling approach can be used to extend the Arnason-Schwarz modeling framework to incorporate directional information from acoustic arrays to estimate survival and characterize the timing and direction of migratory movements of forage fish.

Relationship of water column stability to the growth, condition, and survival of pink salmon (Oncorhynchus gorbuscha) in the northern coastal Gulf of Alaska and Prince William Sound

2012 ◽  
Vol 69 (5) ◽  
pp. 955-969 ◽  
Author(s):  
Sara E. Miller ◽  
Milo Adkison ◽  
Lewis Haldorson
Keyword(s):  
Water Column ◽  
Growth Condition ◽  
Pink Salmon ◽  
Gulf Of Alaska ◽  
Oncorhynchus Gorbuscha ◽  
Biological Parameters ◽  
Prince William Sound ◽  
Pink Salmon Oncorhynchus Gorbuscha ◽  
Fish Condition ◽  
Water Column Stability

Water column stability has been hypothesized to affect growth and ultimately survival of juvenile fish. We estimated the relationships between stability and the growth, condition, and marine survival of several stocks of pink salmon ( Oncorhynchus gorbuscha ) within Prince William Sound (PWS), Alaska, USA, and the northern coastal Gulf of Alaska (GOA) shelf. There was a stronger correlation among the biological parameters of the fish than between the biological parameters and physical conditions. While stability and fish condition during early marine residence in PWS were important to year-class survival, stability of the water column that juveniles experienced as they migrated to the open waters of the GOA did not play a key role in determining survival to adulthood. Below-average stability just prior to capture within PWS combined with positive fish condition was related to increased year-class survival. Our results are similar to previous studies that concluded that slower and weaker development of stratification with a deeper mixed layer depth may be important for juvenile pink salmon survival in PWS.

Temporal and spatial variability of 13C/12C and 15N/14N in pelagic biota of Prince William Sound, Alaska

1999 ◽  
Vol 56 (S1) ◽  
pp. 94-117 ◽  
Author(s):  
Thomas C Kline, Jr.
Keyword(s):  
Stable Isotope ◽  
Phytoplankton Bloom ◽  
Gulf Of Alaska ◽  
Prince William Sound ◽  
Large Herbivore ◽  
Clupea Pallasi ◽  
Carbon Cycles ◽  
Isotopic Signatures ◽  
Carbon And Nitrogen ◽  
Isotope Tracer

Stable isotope ratios of carbon and nitrogen were used to identify seasonal and spatial patterns in carbon and nitrogen and to determine source of energy (Prince William Sound (PWS) versus the Gulf of Alaska (GOA)) for juvenile fishes in PWS. PWS-wide samples of bulk net zooplankton (all noncalcareous zooplankton collected in 335-µm-mesh nets), individual late copepodid stage of the large herbivore Neocalanus cristatus, juvenile Pacific herring (Clupea pallasi), and juvenile walleye pollock (Theragra chalcogramma) were collected in spring, summer, and fall in 1994 and 1995. For bulk zooplankton and N. cristatus, there was a strong 13C/12C gradient but weak 15N/14N gradient within PWS and GOA. Zooplankton 15N/14N was positively correlated with 13C/12C during the phytoplankton bloom but was not correlated during the zooplankton bloom, suggesting a decoupling of nitrogen and carbon cycles. Plankton isotopic signatures suggested a diagnostic 13C/12C for GOA carbon. For juvenile fishes and diapausing copepods in PWS, 13C/12C varied between years, suggesting that the origin of carbon differed between years (GOA more so in 1995 than in 1994). Use of a natural stable isotope tracer provided evidence for biophysical coupling via inferred fluctuations in oceanographic processes.

BIOLOGICAL CONDITIONS OF SHORELINES FOLLOWING THE EXXON VALDEZ SPILL1

1993 ◽  
Vol 1993 (1) ◽  
pp. 287-292
Author(s):  
Sam W. Stoker ◽  
Jerry M. Neff ◽  
Thomas R. Schroeder ◽  
Deborah M. McCormick
Keyword(s):  
Marine Mammals ◽  
Gulf Of Alaska ◽  
Prince William Sound ◽  
Residual Oil ◽  
Exxon Valdez ◽  
Biological Communities ◽  
Upper Intertidal ◽  
Abundance And Diversity ◽  
Environmentally Sound ◽  
Almost All

ABSTRACT Following the Exxon Valdez oil spill of March 24, 1989, in Prince William Sound, Alaska, Exxon conducted a comprehensive shoreline survey program in cooperation with federal and state authorities. Objectives of surveys during the spring and summer of 1989 were to assess the distribution and magnitude of oiling, to evaluate impacts of the oil on key shoreline biological communities, and to identify ecological and archaeological resources requiring special care during the massive cleanup effort that followed. Similar shoreline surveys were performed during the springs of 1990, 1991, and 1992 on all shorelines in Prince William Sound and the Gulf of Alaska suspected of having residual oil. These subsequent surveys were conducted to provide information on the distribution and amounts of residual shoreline oil and to assess the condition of intertidal biological communities in order to make environmentally sound decisions regarding the need for additional cleanup. The following report is based primarily on survey results from Prince William Sound, where most of the heavy shoreline oiling occurred. Although not strictly quantitative, the shoreline surveys provide an unprecedented, broad base of professional observations covering the entire spill-affected area from 1989 through 1992 by which to evaluate spill impacts and recovery. Shoreline surveys documented that the extent of shoreline oiling declined substantially from 1989 to 1992. In 1989, oil was found on about 16 percent of the 3,000 miles of shoreline in Prince William Sound; by the spring of 1991, oil was found on only about 2 percent of the shoreline; and by May of 1992, on only 0.2 percent. In all years, most of this oil was located in the biologically least productive upper intertidal and supratidal zones. In both 1991 and 1992, small, isolated pockets of subsurface oil were found on some boulder/cobble beaches. Most of these deposits were also located in the upper intertidal and were usually buried beneath clean sediments. In almost all cases, the condition of intertidal biological communities improved correspondingly from 1989 to 1992. By the spring of 1991, recovery appeared to be well under way on virtually all previously oiled shores, with species composition, abundance, and diversity levels usually comparable to those of nearby shores that were not oiled in 1989. Recruitment of intertidal plants and animals was observed as early as the summer of 1989, and increasingly through 1991 and 1992. Recruitment was evident even in areas with remnant deposits of surface and subsurface oil, indicating that toxicity levels of the oil had declined substantially and that, in most cases, the residual oil no longer interfered with biological recovery. Observations of birds and marine mammals on or near shorelines surveyed during 1991 and 1992 confirmed that species present before the spill were still present and were feeding and reproducing in areas affected by oil in 1989. In most cases, observed densities were comparable to those recorded prior to the spill, and to those found in similar unaffected areas.

EVOLUTION OF A WORLD-CLASS TANKER ESCORT SYSTEM

2001 ◽  
Vol 2001 (2) ◽  
pp. 1167-1172
Author(s):  
Vincent B. Mitchell
Keyword(s):  
Oil Spill ◽  
Gulf Of Alaska ◽  
Prince William Sound ◽  
The Disabled ◽  
Oil Spill Response ◽  
Subarctic Climate ◽  
World Class ◽  
Best Available Technology ◽  
Pass Through ◽  
Available Technology

ABSTRACT The Ship Escort Response Vessel System (SERVS) of Alyeska Pipeline Service Company (Alyeska) in Valdez Alaska is responsible for overseeing the prevention, preparedness, and response activities for the safe transportation of oil through Prince William Sound. Since the inception of SERVS in 1989, escort vessels have accompanied laden tankers through Prince William Sound from the Valdez Marine Terminal to the Gulf of Alaska, a distance of approximately 70 miles. The tankers pass through the pristine Prince William Sound, which encompasses over 2,500 square miles, with fjord-like topography and a subarctic climate. The evolution of the tanker escort system began with the emergency order issued by the state of Alaska in 1989 immediately after the grounding of the Exxon Valdez. A fleet of 12 vessels, each singular in purpose, was quickly developed: three dedicated pairs of escorts (comprised of an escort response vessel and tug), response barge standby vessels, and four dedicated docking tugs. The emphasis was more on oil spill response than prevention, and there was little interchangeability between vessels and their missions. In subsequent years, a variety of factors has caused changes to the escort system and vessel mix. These included the Disabled Tanker Towing Study, Prince William Sound Risk Assessment Promulgation of Federal Escort Requirements, oil spill response responsibility in the Gulf of Alaska, tanker vapor recovery, reduction in pipeline throughput, and weather restrictions. Additionally, industry instituted voluntary measures such as ice scouts and sentinel standby escorts for inbound tankers in ballast have affected the escort system, in addition to the experience gained in the operation the system. As the escort system matured, there was a marked emphasis and focus on oil spill prevention, fleet modernization, and multipurpose vessels to increase capabilities while maximizing efficiencies. Alyeska/SERVS embarked on a dedicated strategy to upgrade the specialized vessel fleet of 12 vessels to a fleet composed of fewer multipurpose vessels. This strategy encompassed a technological and operational enhancement of the fleet, significantly improving the prevention posture while maintaining the necessary response capabilities. Today, the Alyeska/SERVS escort fleet consists of nine multipurpose vessels. The cornerstones of the escort fleet are the two 10,192 horsepower Voith Schneider enhanced tractor tugs and the three 10,192 horsepower ? drive Prevention and Response Tugs, all specifically designed, constructed, and outfitted for tanker escorting. The combination of these vessels for tanker escorting utilizes complimentary best available technology to ensure the safe transit of tankers through Prince William Sound.

Consumption demand of juvenile pink salmon in Prince William Sound and the coastal Gulf of Alaska in relation to prey biomass

2005 ◽  
Vol 52 (1-2) ◽  
pp. 347-370 ◽  
Author(s):  
Alison D. Cross ◽  
David A. Beauchamp ◽  
Janet L. Armstrong ◽  
Mikhail Blikshteyn ◽  
Jennifer L. Boldt ◽  
...  
Keyword(s):  
Pink Salmon ◽  
Gulf Of Alaska ◽  
Prince William Sound ◽  
Prey Biomass ◽  
Consumption Demand

Pacific salmon (Oncorhynchus spp.) early marine feeding patterns based on 15N/14N and 13C/12C in Prince William Sound, Alaska

2002 ◽  
Vol 59 (10) ◽  
pp. 1626-1638 ◽  
Author(s):  
Thomas C Kline, Jr. ◽  
T Mark Willette
Keyword(s):  
Stable Isotope ◽  
Pacific Salmon ◽  
Isotope Composition ◽  
Gulf Of Alaska ◽  
Whole Body ◽  
Prince William Sound ◽  
Stable Isotope Composition ◽  
Release Date ◽  
Feeding Patterns ◽  
Protein Pool

Nitrogen and carbon mass and stable isotope composition among cohorts of Pacific salmon (Oncorhynchus spp.) released from Prince William Sound, Alaska, hatcheries in 1994 varied widely, suggesting a range in early marine feeding patterns. Analyses consisted of whole-body stable carbon and nitrogen mass and stable isotope composition of selected release-date cohorts that had been identified by implanted coded wire tags (CWT). Nitrogen isotopic and mass shifts suggested that the initial protein pool within individual fish was replaced at different rates among cohorts. There was a notable difference in carbon source dependency among hatcheries. Salmon from the hatchery closest to the Gulf of Alaska had a 13C-depleted carbon signature consistent with Gulf carbon, whereas salmon from the other hatcheries had Sound signatures. Differences in early marine feeding histories among 1994 hatchery-release-date cohorts reconstructed from the stable isotope composition of fry bore no relationship to marine survival pattern. Varied survival rates of 1994 Prince William Sound hatchery salmon were more likely related to the fry size at time of release, the observed differences in growth rate among release cohorts, and predation refuge effects of pen-rearing.

Early Marine Growth of Pink Salmon in Prince William Sound and the Coastal Gulf of Alaska During Years of Low and High Survival

2008 ◽  
Vol 137 (3) ◽  
pp. 927-939 ◽  
Author(s):  
Alison D. Cross ◽  
David A. Beauchamp ◽  
Katherine W. Myers ◽  
Jamal H. Moss
Keyword(s):  
Pink Salmon ◽  
Gulf Of Alaska ◽  
High Survival ◽  
Prince William Sound

scholarly journals EVOS and the Prince William Sound Long Term Environmental Monitoring Program

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
James R. Payne ◽  
William B. Driskell ◽  
David Janka ◽  
Lisa Ka'aihue ◽  
Joe Banta ◽  
...  
Keyword(s):  
Environmental Monitoring ◽  
Ballast Water ◽  
Monitoring Program ◽  
Gulf Of Alaska ◽  
Advisory Council ◽  
Prince William Sound ◽  
Mussel Tissue ◽  
Weathered Oil ◽  
Diesel Spill

ABSTRACT Following the 1989 Exxon Valdez oil spill (EVOS), the Prince William Sound Regional Citizens' Advisory Council began the Long-Term Environmental Monitoring Program (LTEMP) in 1993 to track oil hydrocarbon chemistry of recovering sediments and mussel tissues along the path of the spill in Prince William Sound (PWS) and across the Northern Gulf of Alaska (NGOA) region. The program also samples sites near the Alyeska Marine Terminal (AMT) within Port Valdez, primarily to monitor tanker operations and the resulting treatment and discharge of oil-contaminated tanker ballast water. Over the last 28 years, the program has documented EVOS oil's disappearance at the spill-impacted sites (albeit buried oil still exists at a few unique sheltered locations in PWS). Within the Port, a few tanker- and diesel-spill incidents have been documented over the years, but all were minor and with recovery times of < 1 yr. Of highest concern has been the permitted chronic release of weathered oil from tankers' ballast-water that is treated and discharged at the Alyeska Marine Terminal (AMT). In earlier years (1980s–90s), with discharge volumes reaching 17–18 MGD, up to a barrel of finely dispersed weathered oil would be released into the fjord daily. Over the last two decades, total petrogenic inputs (TPAH43) into the Port have declined as measured in the monitored mussels and sediments. This trend reflects a combination of decreased Alaska North Slope (ANS) oil production and thus, less tanker traffic, plus less ballast from the transition to double-hulled tankers with segregated ballast tanks, and improved treatment-facility efficiency in removing PAH. From the 2018 collections, mussel-tissue hydrocarbon concentrations from all eleven LTEMP stations (within Port Valdez as well as PWS and NGOA regions) were below method detection limits and similar to laboratory blanks (TPAH43 < 44 ng/g dry wt.). At these low background levels, elevated TPAH values from a minor 2020 spill incident at the Terminal were easily detected at all three Port Valdez stations.

Sign in / Sign up

Export Citation Format

Share Document