Ocean 460 - Spring 2000

Welcome to the web site for the year 2000 version of Oceanography 460, Interpretation of Oceanic Data. This 5-credit course is unique in providing our undergraduate oceanography majors with the opportunity (requirement, actually) to conduct original independent research at sea. Although the course emphasizes research and writing, considerable time is given to the development of operational skills such as proposal writing and budgeting, cruise planning and management, and 'scientific seamanship' - the use of oceanographic instruments at sea and in the laboratory.

With the passage of time, some of the links to student papers may have become inoperative. If you would like copies of any of the papers, please contact Prof. Mark Holmes at the address below. And please visit our 2003 web site for Oceanography 443, the successor to Ocean 460.

Course Background | Students and Instructors | Abstracts of Papers

Research Vessels | Cruise Pictures

COURSE BACKGROUND

Oceanography majors at the University of Washington are required to take a two-quarter-long 'capstone' course sequence, usually at the end of their senior year, that provides them with a total immersion experience in proposal writing, cruise planning, and independent oceanographic research. The first (winter) quarter is spent doing background research and then writing a research proposal on a topic of the students' own choosing. The first week of spring quarter is usually marked by frantic cruise preparations, and in early April the class puts to sea to carry out their independent studies. The School of Oceanography makes available to the students a fleet of research vessels ranging from 274 feet to 16 feet in length. Ours is the only program in the U.S. that schedules up to two weeks per year on a major oceanographic research vessel dedicated specically to undergraduate research at sea. Following the cruise(s), the students have 7-8 short weeks in which to analyze their data and prepare both a manuscript and an oral presentation describing the results of their research. The last week of the quarter (late May or early June) is given over to a two-day-long public Symposium where the students present their findings to other faculty, students, state and federal agencies, etc.

This year the students conducted independent research in Hood Canal and northern Puget Sound (including Saratoga Passage, Possession Sound, Padilla Bay, and the eastern Strait of Juan de Fuca. Characteristically, the students took full advantage of the assets available to them; two research vessels and at least three smaller boats were used by various groups to collect data and specimens. Most of the class went to sea for an entire week on R/V Thomas G. Thompson, one of the largest vessels in the U.S. academic fleet. The students were responsible for operation of most of the scientific instrumentation, including the bottom mapping sonar, the ADCP (acoustic Doppler current profiler), the CTD (conductivity, temperature, depth) system, the integrated navigation system, and a variety of bottom samplers (cores and grabs) and plankton nets.

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STUDENTS AND INSTRUCTORS

This year's class included 13 biological oceanographers, 6 chemical oceanographers, and 3 physical oceanographers.

The teaching faculty consisted of:

Mark Holmes - Geological Oceanography and Course Coordinator

Roy Carpenter - Chemical Oceanography

Yves-Alain Vetter - Biological Oceanography

Christopher Krembs - Biological Oceanography

Dan Hayes - Physical Oceanography

Glenn Cannon - Physical Oceanography

We greatly appreciate the efforts and contributions of our external advisers:

Jan Newton, Washington State Department of Ecology

Randy Shuman, King County Department of Natural Resources

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ABSTRACTS OF PAPERS - Alphabetical Listing

Caldwell, Jennifer - DETERMINATION OF THE QUALITY AND MOVEMENT OF PROTEINS AND AMINO ACIDS IN EELGRASS BEDS
Little is known about eelgrass beds and the role they play in coastal carbon and nitrogen fluxes. By studying the amino acid concentrations in the sediment (inside and outside the bed), eelgrass, epiphytes and particulate matter in the water column, I determined that eelgrass beds are acting as a net sink for carbon and nitrogen. Water samples were taken from a boat using a Niskin bottle; samples of eelgrass, epiphytes, and sediment were collected from Padilla Bay by walking from shore at low tide. Samples were analyzed by high-pressure liquid chromatography and an amino acid degradation index. Understanding how eelgrass beds utilize labile organic carbon is essential to understanding their ecology and their role in the coastal ecosystem, and is fundamental to properly protect and maintain eelgrass beds in the future.

Crowley, Jennifer - THE FLUX OF PARTICULATE ORGANIC MATTER ACROSS AN EELGRASS SYSTEM LOCATED IN PADILLA BAY
The carbon to nitrogen ratio of organic matter was determined for all major components of an eelgrass system in Padilla Bay, Washington, during spring 2000. The particles suspended directly in the eelgrass had a higher average C:N ratio than the POM surrounding the bed, 8.95 and 8.26 respectively. Likewise, the sediments in the bed had higher average C:N ratios than the sediments outside the bed (9.73 and 8.889). Due to the high level of eelgrass production during this time it was assumed that the particulate organic matter in the eelgrass bed was comprised of new production (phytoplankton) and resuspended sediment. From this assumption a mixing model was constructed to determine the origin of the water taken from within the bed. From the model results, suspended particles from within the bed were determined to be composed of 11% phytoplankton and 89% sediment-derived particulate organic matter. Using the mixing model results and a comparison of all C:N ratios, the path of organic carbon and nitrogen through an eelgrass system were determined.

Frechette, David - DEVELOPMENT OF A MOLECULAR TECHNIQUE TO ASSESS PARTICLE-ATTACHED AND FREE-LIVING BACTERIAL COMMUNITIES IN MARINE ENVIRONMENTS
A qualitative molecular technique was developed for rapid analysis of microbial diversity in marine environments. A protocol for terminal restriction fragment length polymorphism (T-RFLP) was developed to detect the minimum number of bacterial species present in samples obtained from Puget Sound, WA. The technique used a polymerase chain reaction (PCR) in which one of the two primers was fluorescently labeled at the 5' end and was used to amplify bacterial 16S rDNA from total community DNA. The PCR product was digested with restriction enzymes, and the fluorescently-labeled terminal restriction fragment was detected by laser-scanning with a fluorimager. The T-RFLP technique was tested on samples from two sites in Puget Sound. For both sites, particle-attached and free-living bacterial communities were compared at the surface and the chlorophyll maximum. Different bacterial communities were found at the different sampling sites. Additionally, there were differences in species richness between the particle-attached and free-living communities.

Galindo, Heather - DEVELOPMENT OF A METHOD TO STUDY THE SPECIFICITY OF ASSOCIATIONS BETWEEN A PELAGIC DIATOM, DITYLUM BRIGHTWELLI, AND ITS EPIBIOTIC BACTERIAL ASSEMBLAGES IN HOOD CANAL
Sampling and molecular techniques were developed to characterize the epibiotic bacterial assemblages attached to single cell isolates of the centric diatom Ditylum brightwelli. The first part of the study involves culture maintenance, filtration, and DNA extraction in a 96-well format for the rapid processing of large numbers of samples. The second part develops molecular techniques involving the use of Terminal Restriction Fragment Length Polymorphisms to determine the minimum level of genotypic diversity of the epibiotic assemblages using the 16s ribosomal gene. Preliminary results indicate that individual diatoms isolated from a single water sample exhibit both genetically similar and distinct bacteria in their epibiotic assemblages.

Heller, Marlene - DISTRIBUTION AND SOURCES OF VIBRIO PARAHAEMOLYTICUS IN THE WATER COLUMN OF HOOD CANAL, WASHINGTON IN MARCH AND APRIL 2000
This paper presents new data on abundances of Vibrio parahaemolyticus in the water column of Hood Canal, Washington during March and April 2000. V. parahaemolyticus is a pathogenic bacterium found in estuaries that causes the disease gastroenteritis, and in some cases primary septicimia, as a result of the consumption of contaminated seafood. Salinity, temperature, chlorophyll, oxygen and V. parahaemolyticus abundances were determined for both free-living and particle-attached bacteria at the surface, the chlorophyll max and 1-5 m from the bottom at sites in the main channel, the Skokomish river outflow, and along the shoreline and in the mid-channel around the Great Bend. V. parahaemolyticus abundances were usually greatest in particle-attached size fractions as compared to free-living. A geographic trend was also seen where V. parahaemolyticus was more likely to grow within the canal. V. parahaemolyticus abundances were also seen to be greatest at intermediate levels within the water column and where concentrations of chlorphyll and temperatures were highest. These observations suggest that V. parahaemolyticus is introduced into Hood Canal primarily from bottom currents where they are transported in a cyst phase and that V. parahaemolyticus may proliferate in association with zooplankton and other chitinous material. From a public health and fisheries management perspective, these results suggest that V. parahaemolyticus abundances may increase with increasing eutrophication; an effect that is compounded by the addition of nutrients that pollution adds to the water column of Hood Canal.

Kollasch, Lisa - THE TRANSFER OF AG FROM SEWAGE EFFLUENT TO COPEPODS, AMPHIPODS, ARROW WORMS, AND EUPHAUSIIDS IN HOOD CANAL AND AT WEST POINT, PUGET SOUND
Silver (Ag) concentrations were determined in samples of West Point sewage effluent as well as Puget Sound zooplankton species including amphipods, arrow worms, euphausiids and copepods. The zooplankton collection sites included Hood Canal and just off West Point. Higher Ag concentrations were found in the zooplankton from the West Point station, presumably due to the closer proximity to the wastewater treatment plant effluent. Ag concentrations were lower in copepods compared to the other species sampled (which prey on copepods). This suggests bioaccumulation.

Larson, Noel - SPECTRAL ABSORPTION OF COLORED DISSOLVED ORGANIC MATTER (CDOM) IN THE WATERS OF PUGET SOUND, WASHINGTON
Spectral values of light absorption by colored dissolved organic matter (CDOM) in seawater (CDOM; also known as gelbstoff, gilvin, or yellow substance) play an important part in understanding radiation absorption in surface waters. Seawater samples containing CDOM were collected along a transect in Puget Sound which followed a salinity gradient beginning near the mouth of the Skagit River through the Whidbey Basin, Admiralty Inlet, and into the Strait of Juan de Fuca. Samples were gathered from three depths (0 m, 10 m, near bottom) at twelve stations. Light absorption by each sample was measured throughout the UV- visible range (350 nm- 750 nm) using a spectrophotometer. The range of absorption at 400 nm was 0.702 m^-1 to 0.231 m^-1. The highest absorption by CDOM was found in surface waters near the Snohomish River. The lowest value was in surface waters in the Strait of Juan de Fuca. Absorption coefficients at 400 nm were compared to salinity and DOC. A positive relationship between CDOM absorption coefficients at 400 nm and salinity was observed in samples at all depths. There was a good relationship between CDOM absorption coefficients at 400 nm and DOC in surface samples. These findings may have important applications in the field of optical oceanography to correct for biases in radiation measurements in surface waters and chl a estimates based on remote sensing methods. There may prove to be an alternative method for measuring DOC concentrations in surface waters.

Louis, Cindy - PARTICULATE ARSENIC CONCENTRATIONS IN PUGET SOUND AND LAKE WASHINGTON
Boxcore sampling occurred during spring 2000 to determine particulate arsenic, iron, and antimony concentrations from two stations in Puget Sound (Quartermaster Harbor and Fox Island) and one station in Lake Washington (Madison Park). Samples were partially digested and then analyzed using ICP-AES. The highest particulate arsenic concentrations occurred at the Lake Washington station, followed by Quartermaster Harbor and then Fox Island. The Lake Washington station was the station most enriched in arsenic from the smelter, has the slowest sedimentation rate of the three stations and no visible signs of bioturbation. Both Puget Sound cores had signs of bioturbation, which may have led to some of the inconsistency in the profiles there. The faster sedimentation rates and dilution effect due to bioturbation make it not surprising for the Puget Sound cores to have lower particulate arsenic concentrations.

Macdonald, Eric - FLOW PROPERTIES OF THE WATER COLUMN OVER THE HOOD CANAL SILL, PUGET SOUND, WASHINGTON
The physical properties of the Hood Canal sill were examined in an attempt to further our understanding of water properties over a sill, and extend these results to the physical properties of the entire estuary. A high salinity, low temperature water mass was observed at depth during the flood tide and a fresher, warmer water mass was observed at the surface during an ebb tide. A mean flux of dense water was also seen over the entire study period. And, although they are arguably suspect, Richardson numbers indicated immense mixing over the sill. The movement of distinct density water masses suggested a dense water intrusion over the sill, while also indicating the occurrence of a two-layer exchange flow. The mean landward flux of dense water was also an indication of two-layer exchange flow. Water velocity profiles were obtained by RD Instruments ADCP along a single track above the sill. A Seabird CTD was used concurrently in tow-yo mode to examine the density, temperature, and salinity structure from the higher high water to the lower high water of a spring, semi-diurnal tide.

McHugh, Kevin - CIRCULATION IN POSSESSION SOUND DURING AN EBB TIDAL CYCLE
Low salinity water (<27.5 psu) covers the surface layer of Possession Sound. Vertical stratification throughout Possession Sound appears to limit vertical mixing. At the junction between Possession Sound and Puget Sound Main Basin, vertical mixing does occur, mainly from the local bathymetry. These findings occurred during 6 April 6 2000 aboard the R/V Thomas G. Thompson during an ebb tidal cycle. Three cross-channel transects were undertaken to collect salinity, temperature and current velocity data.

Nichols, Crystal - COMPARISON OF IMPORTANCE OF DIFFERENT SIZE CLASSES OF PHYTOPLANKTON IN PUGET SOUND, WASHINGTON
Size fractionated ¹⁴C primary productivity and biomass of picoplankton (0.2 to 2 mm), nanoplankton (2 to 20 mm), and microplankton (>20 mm) were measured in Hood Canal, Admiralty Inlet, and Main Basin, Puget Sound, Washington State in April 2000. Highest integrated productivity occurred at the transition between Hood Canal and the Main Basin with 12292.32 mg·C·m^-2·d^-1. Microplankton dominated the size-specific primary productivity and biomass at four of the six stations whereas nanoplankton dominated at the remaining two stations from Hood Canal. Nutrient concentrations were found to be fairly high at all stations except the two stations in southern Hood Canal where nanoplankton dominated.

Norbeck, Angela - SEDIMENT FLUXES AS THE MAIN SOURCE OF HIGH AMMONIUM CONCENTRATIONS IN NORTHERN HOOD CANAL AND THE MAIN BASIN OF PUGET SOUND, WASHINGTON
Two seasonal ammonium plumes have been detected in the Puget Sound water column, one over the northern Hood Canal sill, and the other in the Main Basin, near Alki Point. Causes of these occurrences were previously unknown. To test the hypothesis that diffusive ammonium sediment fluxes are high enough to provide the necessary amount of ammonium in the water column, flux rates and nitrogen isotopes were measured. Benthic ammonium fluxes were determined using concentration gradients in the sediments and overlying water. A diffusive flux of ammonium, measuring 0.756 pmol·cm^-2·s^-1, leaving the sediment/water interface in April 2000 appears adequate to supply 23% to 92% of the necessary quantity of ammonium over the Hood Canal sill, the exact value depending on the rate of irrigation. The sediment ammonium flux in the Main Basin, 0.580 pmol·cm^-2·s^-1, is only sufficient to supply 9.5% of the observed ammonium concentration in the overlying water at that location, with a maximum of 38% when irrigation is included. Nitrogen isotopes, determined by mass spectrometry, in the pore water of the sediments at Hood Canal average 13.70 â, while the water column above has an average isotope value of 12.07 â, suggesting a benthic origin of the nitrogen in the ammonium in the water column at the Hood Canal station.

Prentice, Ken - SOLID PHASE BARIUM LEVELS AS AN INDICATOR OF HUMAN IMPACT ON NET PRIMARY PRODUCTIVITY IN PUGET SOUND
Solid phase Ba, Al, and U were measured at four sites in the Puget Sound, WA area. Ba was normalized to Al and used as a proxy for past net primary productivity, while U was normalized to Al in order to determine when benthic reworking effected the Ba record. Two of the sites were selected in order to calibrate the Ba/Al record, while the other two were selected in order to determine past NPP as a function of human impact. Sediments were collected with a piston core, and digested using a total acid digestion technique. Although absolute Ba, Al, and U values deviated from standard reference values it is believed that the trends seen at the sites are representative of the actual geochemical record. The Ba/Al record was found to agree well with both calibration sites, and was subsequently used to determine human impact on the other two sites. In both study sites it was not found that there was no appreciable change in the Ba/Al ratios, and thus net primary productivity, with depth.

Ruef, Wendi - TRACING SEASONAL CHANGES IN CIRCULATION OF HOOD CANAL, PUGET SOUND, WASHINGTON STATE, USING CHLOROFLUOROCARBONS AS CONSERVATIVE TRACERS
Changes in seasonal circulation may be a contributing factor to the intensification of naturally low dissolved oxygen concentrations observed at the southern end of Hood Canal, Puget Sound. Chlorofluorocarbon concentrations measured in water samples taken in December 1999 and April 2000 were used as conservative tracers to observe general circulation patterns and calculate seasonal flow rates and residence times in a 3-box model of the Hood Canal. Flow rate through the deep water at the southern end increased between December and April, from 6.04 x 102 to 1.14 x 103 m³·s^-1, with a consequent decrease in residence time from 153 to 81 d. An increase in flow rate would generally not contribute to low dissolved oxygen concentrations, since more water would flow through at depth and up to the surface, where it could be re-saturated with atmospheric oxygen. Because of annual and seasonal variability, these data are only applicable for the time period between December 1999 and April 2000, but can be added to a larger data set of more seasons and years, which can then be used to make conclusions about the effect of seasonal circulation changes on dissolved oxygen concentrations.

Sackmann, Brandon - VARIABILITY IN EGG PRODUCTION OF NATURAL POPULATIONS OF CALANUS PACIFICUS FROM PUGET SOUND, WASHINGTON
Mesozooplankton secondary production in aquatic food webs is critical in the energy transfer of primary producers to higher trophic levels. Detailed knowledge of copepod reproductive behavior, especially egg production, is required to understand marine heterotrophic food webs. The specific goal of this study was to determine the degree to which egg production of Calanus pacificus correlates with egg size, female prosome length, egg hatching success, and available food concentrations. Samples were collected by vertical net tow from the R/V Thomas G. Thompson on 3-7 April 2000, at six stations along a transect extending from the Main Basin of Puget Sound into lower Hood Canal, Washington. Calanus pacificus females (10-40 individuals per station) were sorted under a dissecting microscope to conduct short-term incubation experiments. After 24-28 hrs the incubations were terminated and released eggs were counted and a random subsample of eggs was sized using an inverted microscope at 250X. The remaining eggs were allowed to hatch for an additional 48 hrs in order to estimate hatching success. Female prosome length was measured using a dissecting microscope and available food concentrations were estimated from fluorescence profiles developed at each station. Egg production was correlated with egg size and female size, but not with hatching success or available food concentrations. This study may elucidate ways in which these parameters can be used to predict and quantify secondary production in many marine systems.

Salnick, Erica - AN INVESTIGATION INTO THE POSSIBLE USE OF CAFFEINE AS A TRACER FOR SEWAGE EFFLUENT IN PUGET SOUND, WASHINGTON, USA
The presence of caffeine in Puget Sound, Washington, USA, in association with sewage effluent discharge could be used as a tracer for the discharge plume. Water samples of 4 L were collected in a transect across a pipe used for the dispersion of sewage effluent by the West Point, Seattle, sewage facility. Duplicate 1 L water samples were filtered through solid phase extraction cartridges and eluted with methanol and an 80%/20% methylene chloride/methanol solution. The resulting 7 mL were evaporated under a gentle stream of nitrogen and re-suspended in 0.5 mL of methylene chloride. Caffeine standards tended to have retention times between 13.9 min to 14.1 min when analyzed by gas chromatography flame ionization detection and sample from the sampling stations near West Point contained chromatographic peaks of differing heights at similar retention times. Upon investigation of these samples by gas chromatography mass spectrometry the peaks were determined to be caused by the presence of phthalates. The results of this study did not provide any indication that caffeine could be used as a tracer for the discharge plume caused by the release of sewage effluent into Puget Sound.

Sauers, Kari - TIDAL CURRENT STRUCTURE AROUND POINT EDWARDS IN PUGET SOUND, WASHINGTON
Field measurements of tidal flow in the triple junction of Puget Sound, Washington, were taken during a 6.5-hour-long maximum ebb tide on 7 April 2000 aboard the R/V Thomas G. Thompson using an RD Instruments ADCP. The objective of this research was to determine if a flow separation occurred north of Point Wells, and then to identify any evidence of eddy formation in this region during an ebb tide. Vertical velocity profiles suggested the possibility of eddy formation just north of Point Edwards; however, the measurement array did not provide enough spatial and temporal coverage to be conclusive. The flow patterns observed in this study demonstrated that the currents in the Main Basin are primarily controlled by local bathymetry.

Sawyer, Richard - NUTRITIONAL QUALITY OF PHYTOPLANKTON AS A FOOD SOURCE FOR ZOOPLANKTON IN PUGET SOUND, WA, DETERMINED BY CHEMICAL COMPOSITION
Various properties of phytoplankton that determine their quality as a food source for zooplankton have been determined through years of research. This study focused on one set of phytoplankton properties (chemical composition) and several food quality indicators (prosome length, egg diameter, and egg production rates) in Hood Canal and the Main Basin. Phytoplankton samples and zooplankton (Calanus pacificus) were collected along a six station transect of these two basins in Puget Sound, WA aboard the R/V Thomas G. Thompson during 3-7 April 2000. Phytoplankton food quality was analyzed for total protein content, carbon/nitrogen ratios, chlorophyll a concentrations, and phaeopigment concentrations using conventional methods. The first goal of this study was to quantify potential spatial variability in chemical composition between the two basins. Second, a correlation between chemical composition and food quality indicators was determined. Variability was evident in all chemical analyses conducted, particularly Hood Canal, which contained steady gradients with most parameters. Chemical composition also correlated well with Calanus pacificus prosome length and egg diameter, and to a lesser extent with egg production suggesting that these parameters were accurate measurements for determining zooplankton size and fecundity.

Scansen, Brian - DISCRIMINATING THE RELATIVE IMPACT OF POINT VS NON-POINT SOURCES OF FECAL COLIFORM CONTAMINATION IN HOOD CANAL, WASHINGTON
Fecal coliform abundance was measured in the main channel of Hood Canal, along the shore, and at the mouth of the Skokomish River, to characterize the extent of fecal contamination in the Hood Canal system. Samples were collected from R/V Thomas G. Thompson and R/V Wee Lander and analyzed via membrane filtration and culture techniques to discriminate the relative impact of a point source of fecal contamination - the Skokomish River - versus a non-point source - land runoff, agriculture, etc. - in the Hood Canal estuary. High coliform abundances were found at the mouth of the Skokomish; the abundances decreased with distance from the river. These high abundances, coupled with a correlation between coliform abundance and salinity, implicate the Skokomish River as a point source of coliform bacteria into the system. Higher and more variable coliform abundances along the shore of Hood Canal as compared to the mid-canal imply non-point sources of fecal coliform entry into the system as well.

Sutton, Lesa - RELATIONSHIP OF OXYGEN CONCENTRATION TO EUPHAUSIID ABUNDANCE, SPECIES COMPOSITION, AND VERTICAL DISTRIBUTION IN HOOD CANAL, WASHINGTON
Dissolved oxygen (DO) concentrations below the biological stress level of 5.0 mg/L persist at depths greater than 15 m in southern Hood Canal. Because this low DO appears to be increasing spatially and temporally, it is important to determine if the low DO has a significant effect on the biological community of Hood Canal. DO concentrations were measured and euphausiids collected throughout the water column at two stations, one in northern and one in southern Hood Canal. Two species of euphausiids, Euphausia pacifica and Thyanoessa raschii were collected. There were significantly more euphausiids collected at the southern than northern station. Euphausia pacifica was the dominant species at the southern station and nearly absent from the northern station. Thyanoessa raschii was found in low, but similar abundance at the northern and southern stations. However, evidence is weak for a relationship between euphausiid abundance, species composition, and distribution and DO concentrations in Hood Canal. Possible alternate explanations for the observed euphausiid community structure include an unexplained NH₄ plume, temperatures below Euphausia pacifica spawning range, and vertical mixing at the northern station.

Welch, Matt - SPRING ABUNDANCE OF ZOOPLANKTON RELATED TO PARTICULATE ORGANIC MATERIAL ACROSS THE HOOD CANAL SILL, PUGET SOUND, WASHINGTON
The density of four classes of zooplankton was calculated from vertical net tows done at three stations around the Hood Canal sill, Puget Sound, Washington. Suspended particulate matter, particulate organic matter, chlorophyll a, and CTD data were taken and used to determine the most important factor in zooplankton distribution. Comparisons were made between stations and day vs. night at each station. A significant link between zooplankton abundance and the availability of food could not be determined, and advection is thought to be the primary factor governing the distribution of zooplankton at this location.

Wood, Neil - A COMPARISON OF PHYTOPLANKTON COMMUNITY COMPOSITIONS AND SPECIES DIVERSITY IN PUGET SOUND, WASHINGTON: MAIN BASIN VS HOOD CANAL
Phytoplankton species diversity and dominant phytoplankton species were determined in two different regions (Hood Canal and Main Basin) of Puget Sound, Washington. Samples from three stations in each region were collected from two depths (surface and chlorophyll maximum) to determine local differences in the phytoplankton community in Puget Sound. Main Basin stations were dominated by the diatoms Skeletonema costatum, Thalassiosira nordenskioeldii, and Ditylum brightwellii. In general, Hood Canal stations were dominated by the dinoflagellate Scrippsiella trochoidea and the diatoms Pseudo-nitzschia spp and Chaetoceros spp. With two minor exceptions, no substantial differences in dominant phytoplankton were observed between the two sampled depths. Mixing of water bodies at the transition of the two regions appears to have created a composite of predominant Main Basin and Hood Canal species at the closest adjacent regional stations. The strong presence of S. trochoidea in the southern Hood Canal stations, in conjunction with lower chlorophyll-a to phaeopigment ratios, point to the end of a recent phytoplankton bloom in this area. Phytoplankton species diversity was higher in Hood Canal than in the Main Basin; this difference may be attributed to the presence of a greater number of microhabitats in Hood Canal (greater shore to volume ratio). While neither hydrographic conditions (temperature, salinity, dissolved oxygen) or nutrient concentrations appeared to be associated with species diversity, the presence of available nutrients may have been related to levels of species diversity at the Hood Canal stations.

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RESEARCH VESSELS (click to expand images)

R/V Thomas G. Thompson

R/V Thomas G. Thompson was the lead ship of the modern AGOR-23 class of oceanographic research vessels; these 274-foot-long ships have a greater endurance, higher speeds, and greater sea-keeping ability than the previous class of vessels that were designed and built in the mid-1960's. Owned by the U.S. Navy and operated by the University of Washington, Thompson carries a crew of 22 and up to 37 scientists and technicians. With over 4,000 square feet of laboratory space, modern deep-sea winches, bow and stern cranes, A-frame, spacious deck working areas, bottom-mapping sonars, and seismic air compressors, Thompson can efficiently accommodate large multidisciplinary scientific missions. An integrated navigation system permits pin-point positioning and station-keeping. The unique Z-drive main propulsion system (the ship has no rudders) and jet-type bow thruster provides the vessel with superb maneuverability, even in high seas. She carries the name of Dr. Thomas G. Thompson, who founded and developed the oceanography department at the University of Washington in 1930.

R/V Clifford A. Barnes

R/V Clifford A. Barnes is a 65-foot-long vessel owned by the National Science Foundation and operated by the University of Washington's School of Oceanography. Her research missions are primarily conducted in the coastal waters off the West Coasts of the U.S. and Canada. Barnes began life as the USCGC Bitt (WYTL 65613). As a Coast Guard vessel, her major missions wer ice operations, search and rescue, and pollution response. She was acquired by NSF in 1982 to begin service as a member of the U.S academic research fleet. Equipped with state-of-the-art navigation equipment, scientific echo-sounders and bottom mapping sonars, and capable of supporting a wide variety of science instrumentation, Barnes provides a flexible platform for lottoral and estuarine studies in Pacific Northwest waters. She carries a crew of two, with accommodations for five scientists. The vessel was named after Dr. Clifford A Barnes, a distinguished professor in the School of Oceanography from 1947 to 1973.

R/V WeeLander

R/V WeeLander is a 23-foot-long Beach Master work boat. She was acquired by the School of Oceanography in 1991 to provide support of shallow water research in the bays and estuaries of the Puget Lowland. Her bow door is ideal for diving operations, and the spacious well deck forward of the two-person pilot house can accommodate a wide variety of oceanographic equipment. WeeLander is trailerable, and has been used in a variety of limnological and geological studies in Washington's lakes. This versatile boat, with it's 'landing craft' bow door, has been informally named in honor of Professor Pierre Welander, a member of the School of Oceanography faculty from 1973 to 1995.

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CRUISE PICTURES (click to enlarge)

Glenn and Kari at the integrated navigation console Thompson's computer lab

Roy demonstrating the Van Veen grab

Lila encountering the "Gumby Suit' during fire and boat drill

Brandon and Brian preparing the plankton net for deployment

Deploying the net from Thompson

Kevin and Kari with the tow-yo CTD package

Preparing the main CTD package for deployment

Richard, Rob, Kevin, Yves, Angela, and Marlene watching the CTD display

Captain Morgan patiently awaits the new plan from Glenn and Kari

Abandon Ship: Jennifer, Lila, Julia, Neil, and Wendi head for the beach

The PO students (Eric, Kari, Kevin) and Dan monitor the CTD cast

Neil hand-lining for plankton

Time for a break: Erica, Ken, David, Heather

Noel and Yves use Thompson's Zodiac for river work

Chris: the biologists are under control

Angela vs the Soutar box core

Heather and Angela: results of a successful Soutar deployment

Ken and Erica preparing to 'weld' sections of piston core liner

Piston core going down

Captain Morgan (3rd from left) teaching Pictionary in the conference room

The final sunrise

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