1998 Funded Projects

Peer-reviewed Projects

BROWN & GIESKES (SCRIPPS INSTITUTION OF OCEANOGRAPHY) - Flux measurements and hydrogeologic studies at cold seepsoff Alaska and S. California

CAVANAUGH (HARVARD UNIVERSITY) - Environmental, physiological, and molecular factors influencing stable carbon isotope ratios of deep-sea chemoautotrophic symbioses

DAVIS (TEXAS A&M UNIVERSITY AT GALVESTON) - A video/data recorder for monitoring behavior and multi-dimensional movements of marine mammals at sea

EMBLEY & CHADWICK (NOAA/PMEL) - Axial volcano: High resolution mapping and monitoring to establish links between hydrothermal vents and perturbations to volcanic systems

HANLON & RUMMEL (MARINE BIOLOGICAL LABORATORY) - Quantifying the reproductive behavior of the commercially important squid Loligo opalescens on spawning grounds in Monterey Bay, California

JAGIELO & ZIMMERMAN (WA DEPT OF FISH & WILDLIFE, NMFS) - In situ studies of rockfish and lingcod: Evaluation of sampling requirements for trawl survey calibration

KLIMLEY (BODEGA MARINE LAB) - Development and implementation of transponding system to track the annual migration of fishes

LEVIN & GIESKES (UCSD, SCRIPPS INSTITUTION OF OCEANOGRAPHY) - Controls on infaunal community structure a Pacific methane seeps

JON MARTIN (UNIVERSITY OF FLORIDA) - Modern fluid venting and its history: Monterey Bay, California

SCHEEL & VINCENT (PRINCE WILLIAM SOUND SCIENCE CENTER) - What is the significance of depth in the ecology of the Giant Octopus?

SHIRLEY (UNIVERSITY OF ALASKA) - Bathymetric distribution of dungeness crabs in bays with and without sea otters

SMITH & VRIJENHOEK(UNIVERSITY OF HAWAII & RUTGERS UNIVERSITY) Yr 2 of 2 - Early Succession, Persistence and Seep Affinities of Whale-fall Communities on the Northeast Pacific Slope

STARR, CAILLIET, & HEINE (MOSS LANDING MARINE LAB) - Movements of fishes associated with natural refugia in Monterey Bay: Implications DWROV(2) for marine reserves in fishery management

TORRES, McMANUS & GOLDFINGER (OREGON STATE UNIVERSITY) - Sources and consequences of fluid discharge along the San Clemente Fault Zone

TORRES & McMANUS (OREGON STATE UNIVERSITY) - Geochemical consequences of gas hydrate formation in sediments of the Cascadia accretionary prism

Developmental Projects

HIGHT & OTA (SANTA CLARA UNIVERSITY) - Marine Map: Mars Pathfinder 3d Visualization, Control and Analysis Tools for Marine Research

RITTSCHOF (DUKE UNIVERSITY) - Sulfide Settlement Cues in Hydrothermal Vent Environments

VOIGHT (THE FIELD MUSEUM OF NATURAL HISTORY) - Development Support for Seamount Study

William Ambrose - Bates College
Benthic response to early-season deposition of algae in the Chukchi Sea

Project Summary: The Arctic Ocean is remote, hard to access, yet critically important to an understanding of the global carbon cycle and global climate change. Recent late-season studies have shifted our perspective from the Arctic Ocean as a biological desert to a site of active carbon cycling. Because of logistic constraints limiting sampling to the late season, the focus of benthic research has been on the relationships between phytoplankton abundance and the structure and function of the underlying benthic community. While such research has demonstrated a tight coupling between pelagic and benthic processes, attempts to construct carbon budgets have shown that high rates of bacterial production and high grazing rates by zooplankton can exceed rates of primary production. The presence of an abundant benthos below net heterotrophic waters presents a paradox. Possible explanations for a concurrent heterotrophic water column and a heterotrophic benthos include spatial and/or temporal discontinuities in the input of biogenic carbon to the benthos. For example, significant amounts of carbon may reach the bottom early in the season before the water column is net heterotrophic. One potential early-season source of carbon to the benthos is ice algae, which dominate primary production in ice-covered water before the phytoplankton bloom.

The object of the proposed research is to investigate benthic dynamics early in the season (May-June) on the shelf and slope of the northern Chukchi Sea, before ice break-up. Ice algae are expected to be the dominant source of carbon to the benthos at this time. The distribution of ice algae, both under the ice and on the seafloor, will be examined using a combination of ROV transects to determine spatial coverage and core collection (ice cores and sediment cores) to quantify algal concentrations. In addition to visual and fluorometric analyses, the composition of the ice algae, the phytoplankton and surficial sediments will be determined by: 1) microscopic examination of algal species, 2)measurement of naturally occurring carbon and nitrogen radioisotopes, 3) HPLC pigment analysis, and 4) lipid analysis. Preliminary data collected in June 1996 indicate that the proposed cruise track will cover areas with a large range in the amount of ice algae still attached to the ice and in fresh chlorophyll on the seafloor.

The second major focus of the proposed research will be to determine the effects of early-season deposition of pigments on benthic respiration and activity. Rates of benthic oxygen consumption and specific estimates of sedimentary microbial activity will be compared between areas which have high concentrations of pigments on the seafloor and areas where pigments have not yet sedimented. Community respiration rates will be determined with on-board incubations at in situ temperatures. In addition, ice algae will be added to incubation cores as a direct test of the importance of this food source to infaunal biota. Data from 1996 indicate that total sediment oxygen demand and bacterial activity both respond rapidly to an input of photosynthetic material. Finally, the rate of oxygen consumption for the dominant epifauna found in the Chukchi Sea will be determined using incubation experiments and density estimates. Recent data from the Barents Sea, the Laptev Sea, and the Greenland Shelf indicate that the epifaunal component can play an important role in remineralizing carbon, yet are seldom included in studies of benthic carbon cycling. ROV images will be essential in determining the densities of epifauna because collections made with an otter trawl in ice-covered waters are not quantitative.

In order to understand the annual cycling of carbon in the Arctic, studies must take place in the early season as well as in the late season. The proposed work will contribute to our understanding of carbon cycling on Arctic shelves to an understanding of the role of oceans in the global carbon cycle. The work will be the first to examine the early-season response of arctic benthic communities to deposition of labile organic mater, and the first study in the Chukchi Sea (and only the fourth in the Arctic) to determine the role of mobile epibenthic organisms in carbon remineralization. Without this information, models of carbon flow and ecosystem dynamics in the Arctic Ocean will remain incomplete.

Kevin M. Brown - Scripps Institution of Oceanography
Flux measurements and hydrogeologic studies at cold seeps off Alaska and S. California

Project Summary: It is increasingly becoming recognized that hydrogeologic processes are very active along continental margins and that they exert a significant control on the dynamics of active tectonic systems, as well as impact thermal, biological, and geochemical processes.

Indeed, groundwater seepage may be volumetrically significant enough to affect the chemistry of the coastal ocean and bottom waters in some regions. Requested are 2-3 additional days of Sea Cliff/ATV time on cruises in the Gulf of Alaska and on the Rose Canyon fault zone offshore of N. San Diego to allow a program of flux measurements to be made on and around cold seeps. The objective of the flux meter deployments are as follows: (1) To determine the magnitudes and scale of heterogeneity in aqueous and geochemical fluxes across regions of focused and diffuse flow. (2) Ground truth the relationships between the gradients in shallow pore water chemistry and our surface flux rate determinations. (3) Conduct collaborative interdisciplinary research into the interrelationships between flux rates, seep fluid chemistry, and vent biology. Lisa Levin, Anthony Rathburn, Joris Gieskes, and Bob Hessler at SIO propose to examine the community structure of methane seep sediment infauna in the northeastern Pacific Ocean in relation to geochemical properties of the sediments and to the larger oceanographic setting (current systems and biogeographical regimes). They will be testing hypotheses concerning the influence of the fluxes and epibiota (microbial mats, symbiont-bearing clams and tube worms) on infauna. It seems logical that the flux measurements and biological studies should be conducted at the same locations to obtain proper quantitative interrelationships.

Known regions of significant seepage in active tectonic regions off Alaska and San Diego will be targeted using a newly developed water and geochemical flux meter that is capable of measuring diffuse linear fluid velocities through the sediment surface on the order of 0.05 mm y--1 We will be able to deploy 8 flux meters by submersible. A further 8 independent meters with acoustic releases can be dropped from the ship in the surrounding regions to ascertain background flux patterns. The 16 meters will allow us to make direct measurements of both the diffuse and focused components of the hydrogeologic system on a scale that has never been approached before. A new version of the meter is also currently being developed for studies at seeps where dissolved gas concentrations and fluid advection rates are high. The high rate flux meter will be capable of collecting pressurized water samples that can be analyzed later to give a quasi-time record of both the ionic and dissolved gas concentrations in seep fluids migration through the meter. This work will be undertaken in collaboration with Dave Hilton (at SIO) who is interested in the interrelationships between hydrocarbon and the rare gases and the utilization of such seeps to estimate volatile fluxes associated with plate convergence.

Colleen M. Cavanaugh - Harvard University
Environmental, physiological, and molecular factors influencing stable carbon isotope ratios of deep-sea chemoautotrophic symbioses

Project Summary: Stable carbon isotopes as molecular tracers have been fundamental to the elucidation of carbon sources utilized at the hydrothermal vent ecosystems. Invertebrate-chemoautotrophic bacteria symbioses at hydrothermal vents fall into two groups whose tissue stable carbon isotope values are isotopically-depleted ( 13 C = -27% to -35%) or isotopically enriched ( 13 C= -9% to -15%). Recently, we hypothesized that these differences were due to symbiont fixation of carbon dioxide by different forms of the enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). There are two structurally and kinetically distinct forms of Rubisco present in autotrophic organisms, called Form I and Form II Rubisco, which differ in their kinetic isotope effect with respect to CO2, resulting in different degrees of fractionation during carbon fixation. Indeed, evidence has been presented that in the majority of species examined, the symbionts encode and express a Form I Rubisco in the isotopically-depleted group and a Form II Rubisco in the isotopically - enriched group. In enzyme purified from free-living bacteria studied to date, Form II Rubisco results in less fractionation than Form I and therefore could result in isotopically heavier values in invertebrate-bacteria symbioses.

In contrast, vesicomyid clam symbioses, which are in the isotopically-depleted group, express a Form II Rubisco. The objective of this proposal is to determine the environmental, physiological, and molecular factors which result in the apparent anomalous 13 C values. Four hypotheses, which could result in the depleted values observed in these symbioses, will be evaluated: (1). The dissolved inorganic carbon used by the clams is depleted in 13C. (2). The internal pool of inorganic carbon in vesicomyids is depleted in 13C. (3). Initial carbon fixation in vesicomyids, is catalyzed by other carboxylating enzymes which discriminate against 13C to a greater extent than vesicomyid symbiont Form II Rubisco. (4). Vesicomyid Form II Rubisco discriminates against 13C to a greater extent than previously described Form II Rubiscos. Vesicomyids adapted to survive high (Calyptogena magnifica) and low (Calyptogena pacifica) CO2 environments, as well as diffuse hydrothermal vent fluid samples, will be collected using DSV ALVIN from the East Pacific Rise and Juan de Fuca Ridge, respectively.

To assess whether physiological or environmental factors are responsible for depletion of 13 C in the CO2 fixed by Rubisco, stable carbon isotope ratios of the CO2 from hydrothermal fluids potentially available to the symbioses, and from internal pools of the hosts will be analyzed. In order to determine the importance of the Form II Rubisco for dictating the 13 C in the symbioses in which it occurs, the enzyme from the vesicomyids C. magnifica and C. pacifica will be characterized in detail. The enzyme will be sequenced for comparison with previously examined Form I and Form II Rubiscos. Following the purification of the enzyme, detailed biochemical analysis will be conducted and the kinetic isotope effect of this Rubisco determined by high precision methods.

The recognition of different Rubisco forms being utilized for carbon fixation may have far reaching implications, beyond interpretations of a carbon cycling at hydrothermal vent ecosystems. The recent discovery of a Form II Rubisco in dinoflagellates indicates that this enzyme is not confined to the bacterial autotrophs, and may well explain the isotopically heavy 13 C values of organic matter recovered from the open ocean. Accurately resolving the effects of various forms of Rubisco, as well as the effects of environmental and physiological factors, may have a tremendous impact on interpretation of 13 C data in ecological and paleontological studies.

Randall Davis - Texas A&M University at Galveston
A video/data recorder for monitoring behavior and multi-dimensional movements of marine mammals at sea

Project Summary: We propose to design and fabricate a small video/data recorder that can be attached to free-ranging marine mammals in order to observe their underwater behavior, track their three-dimensional movements, and simultaneously record data on their environment. We will also create software for the post-deployment analysis of the video recordings and data that includes time-synchronized video and data windows and a fully interactive virtual environment with an animated, three-dimensional dive path and oceanographic variables. Finally, we will test the new video/data recorder and analytical software during Years 2 and 3 (1998 and 1999) of a three year, NSF-funded study of the foraging behavior of deep diving Weddell seals (Leptonychotes weddellii) in Antarctica.

We have developed specifications for an advanced video/data recorder and operating software. The system is broadly composed of three components. One is an onboard micro-controller with software that will control the video/audio tape recorder and data acquisition from the pressure, speed, bearing, temperature, sonar and other transducers. Data will be stored on removable 4 megabyte PCMCIA cards. The second is a high performance night vision camera that is 1000-times more sensitive than a conventional, low light sensitive CCD camera. The third component is a hydrodynamically shaped housing that is pressure resistant to a depth of 2,000 m. We have successfully developed and tested three prototypes of the proposed video/data recorder: one on an ocean-trained bottlenose dolphin (Tursiops truncatus) and the second on a free-ranging elephant seal (Mirounga angustironstris). The third generation instrument will be used during the first year (October to December, 1997) of our NSF-funded study of Weddell seals in Antarctica. Fabricating and testing these prototypes has been crucial in our plan for the advanced video/data recorder described in this proposal. Processing the large amounts of video, audio and other data that will be collected with this system will be challenging. To analyze these multimedia data sets, we will develop software that integrates video recordings, audio, graphical data displays and fully interactive virtual environment with an animated, three-dimensional dive path. This software will be designed for a Pentium-class personal computer to facilitate the analysis and interpretation of multimedia data in the field.

Robert W. Embley - NOAA/PMEL/OERD
Axial volcano: High resolution mapping and monitoring to establish links between hydrothermal vents and perturbations to volcanic systems

Project Summary: The primary objectives of this proposal are to: 1) develop detailed base maps of the venting systems near the summit of Axial Volcano on the Juan de Fuca Ridge (JdFR) against which future changes induced by volcanic events can be measured and quantified, and 2) establish initial year- long time series of horizontal strain measurements on the shallow portions of both rift zones where diking events are likely to occur in order to quantify the extent of crustal deformation. Data from these efforts will test two hypotheses: (1) two classes of geologic structures at Axial Volcano host hydrothermal systems, fault-controlled and dike-controlled, and these two environments are distinct in their chemistry and biology and respond differently to volcanic events, and (2) that volcanic intrusions represent inputs of heat and chemicals into the shallow crust and cause sudden permeability increases that measurably perturb hydrothermal systems and their biota. This effort is complementary to a Sea Grant proposal (submitted) that seeks to establish relationships between variations in vent fluid chemistry and the community structure of the subsurface biosphere.

Specific goals of the project include 1) investigating the influence of seafloor geology on vent distribution and character, 2) recovering and redeploying long-term monitoring instruments to detect and understand volcanic perturbations, so that they can be related to changes in the hydrothermal and biological systems, and 3) further developing deep-sea technology and the scientific capabilities of remotely operated vehicles (ROVs). These baseline surveys will be, in part, preparation for future scientific responses to volcanic events at Axial Volcano; to fully document the changes such events produce, it is necessary to know the current state of the system in detail.

One of the most significant results in mid-ocean ridge science is the recent evidence that seafloor venting systems are not static and unchanging. We now know that they are dynamic and subject to dramatic perturbations from the seafloor volcanoes that host them. We hypothesize that the hydrothermal systems of Axial Volcano undergo frequent perturbations because of recent evidence from monitoring data, sampling results, and the long-term record of robust magmatism focused there. The injection of dikes and the eruption of lavas on the seafloor are clearly critical to the creation of shallow hydrothermal systems, and probably play a key role in the formation of event plumes. Therefore, the environment at Axial Volcano is ideal for studying the dynamic character of hydrothermal systems and their relation to the subsurface biosphere, because magmatic events cause the subsurface bacterial communities to frequently "outcrop" at the surface in the vent systems of Axial. A goal of the NOAA/PMEL VENTS Program is to study the geology and hydrothermal systems of Axial Volcano over the next several years in order to understand the interplay between volcanism and hydrothermalism and to be able to document changes associated with volcanic events. We propose to use the new ROPOS ROV on the newly commissioned NOAA Ship Ron Brown in the summer of 1998 to accomplish these goals.

Roger T. Hanlon - Marine Resources Center
Quantifying the reproductive behavior of the commercially important squid Loligo opalescens on spawning grounds in Monterey Bay, California

Project Summary: California's most valuable fishery is now Loligo opalescens, but this is a very recent development. In 1996, the fishery was worth about $33 million, and the squid fishery continues to be targeted by more fishermen each year since other marine resources of the West Coast are fluctuating. These squids have a brief 1-year life cycle and congregate near shore to spawn. They are fished directly on the spawning grounds. Fisheries managers at the state and federal levels are concerned that the population may be near maximum exploitation, yet they have practically no data on the mating system or the reproductive potential of individual squids. Are the behavioral mechanisms of Loligo opalescens flexible enough to withstand this high level of fishing pressure? To address this fundamental question, first it is necessary to obtain in situ observations of the full range of reproductive behaviors. This proposal outlines quantitative methods of behavioral observations that will lay the groundwork for future studies on the reproductive biology of L. opalescens. A NASA-supplied ROV will be used to acquire extensive ad libitum and scan samples of squid behavior on communal egg masses in the field, both during the day and at night. SCUBA divers, using NITROX and handheld video cameras, will augment the ROV data by conducting extensive focal animal samples of mating pairs during the day. A major objective is to determine whether it leads to multiple paternity of individual egg capsules. If so, this sort of robust mating system can withstand targeted fishing pressure, provided that the fishing method does not selectively remove, for example, the fittest males. A second objective addresses whether mating and egg laying occur predominantly during the day, or during the night when fishing pressure is greatest. Thirdly, with these methods it will be possible to begin to assess how many times an individual female mates and lays eggs in one day, and whether females are terminal spawners. When this field work is later integrated with laboratory experiments, then specific aspects of sexual selection theory can be tested experimentally by manipulating the size and combination of squids in a school, and assessing paternity success with molecular methods. This is an opportunity to acquire baseline information on reproduction in L. opalescens before this heavily exploited resource suffers the same fate as other valuable, yet depleted, West Coast fishery species

Thomas Jagielo - Washington Department of Fish & Wildlife
In situ studies of rockfish and lingcod: Evaluation of sampling requirements for trawl survey calibration

Project Summary: Trawl surveys conducted by the National Marine Fisheries Service (NMFS) provide the major source of fishery independent information used in west coast groundfish stock assessments. These assessments are conducted to set levels of Allowable Biological Catch (ABC) needed for harvest management of stocks in the Pacific Fisheries Management Council (PFMC) management zone off the Washington/Oregon/California coast. However, the trawl surveys have been criticized for their unknown catchability and their ability to representatively sample all habitats.

Calibration of the catchability and the representativeness of the trawl surveys is needed to improve the precision of groundfish stock assessments. A study to calibrate the trawl survey estimates must be able to (1) compare trawl survey catchability against a known reference (i.e. in situ observations from a submersible) and (2) discriminate real differences in abundance among habitat types.

This pilot study was designed to determine if the submersible survey method can be used to assess trawl survey catchability and provide a meaningful comparison of fish densities between trawlable and untrawlable habitats. The specific objectives of this pilot study are to (1)qualitatively assess the catchability characteristics of the submersible and (2) determine the size of an experiment (e.g. number of submersible dives) needed to obtain sufficient statistical power to reliably compare fish densities in trawlable and untrawlable habitats.

If the pilot study demonstrates that the submersible method can be used to assess trawl survey catchability and that reliable measurement of density differences is feasible, a trawl survey calibration study will be designed to complement selected tows during a future NMFS trawl survey in the US-Vancouver area. The US-Vancouver area is of particular interest because a relatively large portion of it appears to be untrawlable.

Sidescan sonar will be used to thoroughly map the study area, which includes both trawlable and untrawlable grounds. Submersible dive sites will be randomly selected in both habitat types. The submersible vessel, Delta, will be used to estimate fish densities at these dive sites. The data will be used to estimate quantities needed to determine the sample size requirements for the future trawl survey calibration study.

The primary target species for this project are lingcod (Ophiodon elongatus) and canary rockfish (Sebastes pinniger). Other species from the Sebastes complex may also be included, depending on their abundance in the study area and our ability to identify and count them. This group would most likely include bocaccio (S. paucispinis), silvergray rockfish (S. brevispinis), greenstriped rockfish (S. elongatus), yelloweye rockfish (S. ruberrimus), Pacific ocean perch (S. alutus), redstripe rockfish (S. proriger), rougheye rockfish (S. aleutianus), and yellowtail rockfish (S. flavidus).

A. Peter Klimley - Bodega Marine Lab
Development and implementation of transponding system to track the annual migration of fishes

Project Summary: There will be three main objectives to this one-year study. Firstly, we will improve the accuracy of geolocation estimates by current archival tags. Secondly, we will work with the engineers of VEMCO Limited to develop an archival tag and listening station system capable of acquiring positional fixes stored in the tag's memory without recovering the tag. Thirdly, we will deploy five prototype tags on white sharks at a site with an advanced listening station that will retrieve records of their long-distance migratory movements while away from the site.

We have chosen to develop a prototype transponding geolocation tag for the white shark in preference to a wide variety of potential species for the following three reasons. Firstly, the initial prototype transmitter will have to be large in order to accommodate components of a geolocation archival tag and transponder. A unit of this size will have a reduced effect on the behavior of a large species. Secondly, the positional error to geolocations will be small relative to the distances moved because individuals of this species make long-distance migrations (Klimley, 1985; Bruce, 1992). Thirdly, the probability is high that we will retrieve a record of geolocations from a white shark tagged at a seal colony with a listening station situated there. White sharks return repeatedly to the same seal colonies (Ferreira & Ferreira, 1996; Klimley & Anderson, 1996; Strong et al., 1996).

Specifically, we will improve the accuracy of the astronomical algorithms based upon recordings of the light changes occurring during dawn and dusk measured with a multi-spectral radiometer recently built with NURP funds. CHAT acoustic transmitters will be outfitted with light and depth sensors and improved geopositional algorithms. These tags will be able to download a record consisting of daily/weekly longitudes and latitudes stored in memory to electronic listening stations deployed at sites at which the tagged fish aggregate. We will attach large prototype tags to five white sharks either at Año Nuevo, South Farallon Island, or Point Reyes Headlands and modify an acoustic listening device currently situated at one of these sites so that it communicates with CHAT tags.

Finally, Rick Starr of UC Davis and I will submit a proposal during the following year to NURP to tag five rockfish or lingcod in Monterey Bay with smaller versions of the prototype. We will upgrade a listening device, currently used in a NURP-sponsored study of rockfish movements, to acquire records of daily or weekly position fixes stored in the memory of the tags. Our two-year objective is to develop a network of advanced listening stations capable of acquiring records of the long distance migratory movements of the many medium-sized, commercially important fishes.

Lisa A. Levin - Scripps Institution of Oceanography
Controls on infaunal community structure a Pacific methane seeps

Project Summary: Seep environments, where reduced compounds are vented from the seabed through dewatering or tectonic processes, are now known to be common features of the Pacific margin. To date most biological research on seep biota has focused on the distributions, taxonomy and nutrition of large, epibenthic taxa. Very little information exists about the organisms dwelling in seep sediments. We propose to examine the community structure of methane seep sediment fauna in the northeastern Pacific Ocean in relation to geochemical properties of the sediments and to the larger oceanographic setting (current systems and biogeographic regimes). We propose to sample four bathyal seep sites and adjacent non-seep sites by submersible and ROV to characterize sediment geochemistry, macrofauna, metazoan meiofauna, and foraminiferal community structure and bioturbation regimes. The influence of epibiota (microbial mats, symbiont-bearing clams and tube worms) on infauna will be examined. Dive series are scheduled off Oregon and northern CA in Oct. 1997. This renewal proposal requests two additional dive series, one in the Gulf of Alaska and off southern California, for 1998. Comparisons will be made among infauna from methane seeps, nearby non-seep bathyal environments, and various low-oxygen, organic rich settings or hydrothermal settings (using existing data) in an effort to understand factors controlling the composition, diversity, lifestyles, nutritional properties and bioturbation regimes of seep communities. The eventual goal is to place seep communities in a more general deep-sea context, effectively integrating understanding of seep environments with that of other bathyal settings. We emphasize that examination of multiple Pacific methane seep sites (and nearby non-seep sediments) will maximize our ability to generalize about the influence of seeps on infaunal community structure.

An additional objective is to assess the nutritional sources of seep infauna, using stable isotopic analyses and enzyme assays. With this information we hope to assess the dependence of macrofaunal and foraminiferal communities on reduced compounds associated with seeps. Knowledge of nutritional sources also will have implications for use of foraminifera as indicators of paleoenvironments. Macrofaunal investigations have contributed much to conceptual understanding of deep-sea benthic processes, but have largely bypassed seep environments. In contrast, the foraminifera, though widely studied in a paleoceanographic context, have been largely neglected as a component of the modern fauna. Where modern foraminiferal assemblages have been examined, metazoan faunas have typically been ignored, thus substantial benefit should result from simultaneous emphasis on both groups.

A substantial matching contribution is being provided by the State of California and the SIO Directors Office for faculty, post-doc and technician salaries.

Jon Martin - University of Florida
Modern fluid venting and its history: Monterey Bay, California

Project Summary: The primary objectives of this proposed work are: (1) to identify origins and quantify fluxes of fluids venting from cold seeps in Monterey Bay, CA, and (2) to use chemical and isotopic alteration of sediment in the vent conduits to identify timing of transient flow. Fluid seeps have been extensively studied at convergent margins because they are important for a variety of biological, chemical, and geological processes. Seeps are also common at transform margins, such as Monterey Bay, yet little work has been done on the hydrogeology of this tectonic environment. In both environments, fluid fluxes are poorly known. Flux calculations based on direct measurements of flow rates from conduits typically are orders of magnitude greater than the volumes of fluid contained within the pore spaces. This discrepancy stems from lack of information on the origins of the fluids and the mechanisms driving flow. Explanations for the discrepancy include: infiltration of meteoric water, small scale convection of seawater into the vent conduits, and transient flow, which typically is not accounted for in flux calculations because little is known about the duration of flow.

The proposed objectives will be met through chemical and isotopic measurements of fluid and sediment collected from five sites in Monterey Bay, four at active cold seeps and one at a putative fossil cold seep. The cores will be collected using the MBARI-operated ROV Ventana and Navy-operated ATV. These vehicles can collect 1 m long cores in precisely navigated, short transects (10 to 100 m long) across vent conduits, which is impossible using conventional coring from surface ships. Variations in compositions of pore fluids from within to outside the conduits will identify the location of the conduits' boundaries. Fluids derived from deep sources will have chemical and isotopic compositions (including SO4, sulfide, methane, and Ba concentrations, 87Sr/86Sr ratios, 13CDIC and 13CCH4 values) that are highly altered from seawater. Alternatively, fluids derived from small-scale convection will have compositions that are only slightly altered from seawater values. These pore fluid compositions should enrich vent conduits in metal sulfides and barite, and depending on the extent of convection, metal oxides should be enriched outside of the conduits. The distinct carbon and strontium isotopic composition of the venting fluid should also be recorded by benthic foraminifera. In contrast, foraminifera living at times of no venting should have normal isotopic compositions. Thus, dating boundaries between normal and altered foraminifera should reflect the duration of venting. Dating will be done using the 14C composition of planktonic foraminifera and wood fragments, which are abundant in these sediments.

Results from this work will be important for benthic biologists and ecologist who work on cold seep communities because it will constrain the fluxes and availability of nutrients to the communities, as well as the life span of the communities. It also represents the first detailed and comprehensive study of hydrogeology of a transform margin, thereby providing an important comparison with recent work on convergent margins. The results will be directly applicable to NURP's Monterey Bay Initiative, which includes questions about the sources and consequences of subsurface fluid transport. The proposed work will provide thesis topics for one graduate student and one undergraduate student, thereby enhancing their education.

David Scheel - Prince William Sound Science Center
What is the significance of depth in the ecology of the Giant Octopus?

Project Summary: The Giant Octopus (Octopus dofleini) is an important component of coastal ecosystems from the Pacific Northwest to Japan, both as predator and prey of economically important species (e.g. prey: crabs, clams, shrimp; predators: dogshark, halibut, cod, and pollack). The ecology of O. dofleini remains an enigma throughout many parts of its life-history. In several shallow-water studies (to 30 m depth), important components of the habitat of juvenile Giant Octopuses have been described. However, these and other studies suggest that large, reproductively mature O. dofleini may be restricted to deeper water. Because access to water below 30 m is difficult, little is known of the habits and recruitment of deep-water octopuses. This study will be the first to provide detailed knowledge on habitats selected by deep-water O. dofleini and will provide a test of the hypothesis that shallow water provides unique habitat for juvenile octopuses in Prince William Sound, AK.

Juvenile O. dofleini occur in shallow water near the bases of rock ridges. Typically, boulders resting on sand or gravel near ridges provide dens. In Prince William Sound, a series of descending submarine ridges (adjacent to an existing octopus study site) provides a natural experiment to test the hypothesis that habitats selected by O. dofleini in shallow water have unique characteristics important to juveniles. Two predictions will test this hypothesis: (1) the presence of significant numbers of juvenile-sized octopuses at deeper depths (compared to shallow-water) would indicate that large deep-water octopuses do not necessarily recruit from shallow habitats, (2) no significant changes in habitat associations across depth would indicate that major predator, foraging, and denning constraints do not change with depth for O. dofleini.

Using a submersible capable of surveying rock ridges, three 1000 m transects will be run along ridges at each of four different depths: 10-40 m, 50-80 m, 90-120 m, 150-200 m. In cooperation with a pot fisherman, up to 8 octopuses will be captured and released with implanted sonic transponders, 2 at each depth, just prior to the submersible expedition, allowing us to track octopuses to preferred habitat. Transects of 1000 m will be run by the submersible near the relocations of these octopuses. Along each transect, locations of octopuses and octopus dens and associated habitat characteristics will be recorded. Feeding litter will be recorded on video and collected from octopus dens to identify prey species and sizes. Octopuses within dens will be extracted and subsequently measured using a twin-laser scale mounted on a video camera.

Because shallow-water octopus habitats have been studied in Prince William Sound, additional data from deeper surveys will make this the most comprehensive study of Octopus dofleini ecology in one area; and the only one to examine the habitats of deep-water individuals. An understanding of the habitats and needs of reproductive-sized O. dofleini is increasingly important. Demand from overseas may provide a market incentive to develop the Alaska fishery on this species. Meanwhile, indications of decline across its range leave the status of this octopus in question. Studies of the ecology of octopuses in deeper water are needed to resolve questions about the fishery potential of O. dofleini. Determining whether these deep-water octopuses are recruited from intertidal rearing grounds will also aid subsistence users in making decisions about their harvest rates. This study addresses NURC programmatic goals of fisheries research and shelf ecology. Clarifying the relationships between depth distribution and life history and habitat use may have more general relevance to understanding patterns of coastal ecosystem biodiversity and the Giant Octopus's changing role as predator and as prey across various depths.

Thomas C. Shirley - University of Alaska
Bathymetric distribution of dungeness crabs in bays with and without sea otters

Project Summary: The objective of the proposed research is to determine the bathymetric distribution of the Dungeness crab, Cancer magister, at six sites in the Glacier Bay area. Three of the six sites have established populations of sea otters. An ROV or submersible would be used to directly observe bathymetric range, abundance and behavior of Dungeness crabs in waters from 10 to 210 meters in depth. These parameters would be correlated with several other documented factors (the presence of sea otters; seabed topography and gradient; sediment type; flora and fauna). This study would expand our knowledge of an important commercial species that is at present harvested only in shallow waters. If it is found that a significant population of Dungeness crabs exists at depths deeper than normally harvested the information could be valuable for management of crab stocks. The impact of sea otter predation on the crab population in shallow waters may prove to be less serious if it is found that the crabs move to deeper depths in response to predation or if an abundant population of crabs exists at depth to replenish shallow water stocks.

Craig Smith - University of Hawaii
Early Succession, Persistence and Seep Affinities of Whale-fall Communities on the Northeast Pacific Slope

Project Summary: Deep-sea chemoautotrophic communities on whale carcasses are now documented from at least 6 sites in the North Pacific and 8 sites in the fossil record. Our studies indicated that taxonomically similar communities develop on lipid-rich whale bones throughout southern California, and that these communities share at least 7 species with the fauna from distant hydrothermal vents, and at least 4 species with northern California seeps. Nonetheless, little is known concerning (1) early faunal succession on freshly sunken whale carcasses, (2) the persistence times of whale-bone chemoautotrophic assemblages, and (3) faunal relationships between whale falls and nearby southern California seeps. Such information is essential to evaluating the dynamics of whale-fall habitat islands and their importance as dispersal stepping stones for sulfophilic species at the seafloor.

We thus propose to use an ROV to study three whale carcasses (two implanted and one natural) and one seep on the seafloor off southern California. The carcasses are of varying ages, allowing data collection at t=0.33 y, 1 y, 2 y, 3.4 y, 7 y and >14 y since carcass arrival at the seafloor. The seep (that in San Clemente Basin) is 50-120 km up-current from our whale falls, and thus a likely source of seep-fauna propagules. We will collect sediment cores, faunal and bone samples, and photographic data at various times from these sites to address the following hypotheses:(1) Fresh whale falls cause intense local organic enrichment that fosters a highly specialized (initially heterotrophic) resident faunal assemblage. (2) Components of this heterotrophic assemblage remain for years after disappearance of the whale soft tissue. (3) The persistence times of whale-bone chemoautotrophic assemblages are skeleton-size dependent, attaining > 14 y on the remains of large baleanopterids and < 7 y on small gray-whale carcasses. (4) The faunal assemblages at the San Clemente seep and the southern California whale skeletons share a number of species, but there is not complete community overlap. (5) For those species occurring I n both San-Clemente-seep and whale-skeleton habitats, significant gene flow can occur between seep and whale-skeleton populations. To test these hypotheses, 6 d of ROV (or submersible) time will be required in 1997, and 9 d in 1998.

This project will substantially improve understanding of the dynamics of whale-fall communities, and their potential influence on the dispersal and evolution of chemoautotrophic assemblages in the northeast Pacific. It will also provide the first data concerning deep-sea faunal response to intense local organic loading, yielding insights into community response to natural and anthropogenic enrichment events (e.g., deep-sea relocation of sewage sludge). Finally, through collaboration with a biotechnology firm, this project may provide cold-adapted, lipolytic enzymes with broad industrial applications in cold-water detergents.

Starr, Cailliet, & Heine - Moss Landing Marine Lab
Movements of fishes associated with natural refugia in Monterey Bay: Implications DWROV(2) for marine reserves in fishery management

Project Summary: Recent stock assessments conducted by the Pacific Fishery Management Council (PFMC) have indicated large population declines for commercially harvested species. These declines have led to discussions about the need for alternative fisheries management strategies, such as the use of marine fishery reserves. Although fishery reserves are rapidly being established, their effectiveness in fisheries management is poorly understood and refugium concepts largely are untested.

The existence of natural harvest refugia in Monterey Bay provides a unique opportunity to quantitatively test some of the proposed benefits of marine reserves. This proposal is the second year of a NURP funded project to study the range and frequency of fish movements inhabiting sonic-tagged rockfishes and describe species-specific home ranges and movements using hydrophones, submersibles and ROV. Objective 2 is to test the hypothesis that large predatory rockfishes on the flanks of submarine canyons remain in a small home range and ambush prey as they are advected upslope or move up into the water column or onto the shelf to feed. Both objectives have implications for marine reserves as management tools and models of energy flow pathways relative to the Monterey Submarine Canyon.

Prior to submersible operations, at least ten rockfish will be captured from rocky habitats on the flank of Soquel Canyon. Acoustic transmitters will be surgically implanted in the large rockfishes using techniques that have been refined in laboratory and field sites. Vemco V16 series transmitters will be used in tagging operations. The transmitters will be 16 mm wide and 65-90 mm long, with a weight in water of 10-16 g. Bocaccio, the targeted species of rockfish, are greater than 400 mm total length and weigh more than 3 kg. Fish will be tagged with pressure sensors to enable monitoring of vertical, as well as horizontal, movements. Transmitter power will be 153-159 dB re 1 uP @ 1m; allowing signal detection at a range of 1000 m under expected sea conditions. These techniques have been successfully tested in both laboratory and field conditions.

Fish will be returned to dGPS locations from which they were captured, and tracked at first by surface vessels. Two weeks after tagging, a directional hydrophone mounted in a manned submersible will be used to locate and visually evaluate tagged fishes. The submersible will then be used to place an array of hydrophones and receivers around the shelf habitats frequented by tagged fish. The array of receivers will enable the continuous tracking of horizontal and vertical fish movements for a ten week period.

An understanding of fish movements is especially critical information needed to properly design reserve sizes, shapes and locations. The results of this work should provide important information related to home range and frequency of emigrations from harvest refugia. This project will also provide information about the transfer of energy and materials between benthic and pelagic habitats.

Marta Torres - Oregon State University
Sources and consequences of fluid discharge along the San Clemente Fault Zone
Project Summary: Submarine fluid venting at convergent plate boundaries has been recognized over the past ten years as an important, yet understudied, process in marine sciences (COSOD-2, 1987; Moore and Vrolijk, 1992, FUMAGES, 1997). The eastern Pacific margin is characterized by a variety of tectonic settings where active venting of fluids and gases have been documented (e.g. Kulm et al., 1986; Carson et al., 1991; Torres et al., 1994; Bourgois et al., 1993; Suess et al., 1992; Kastner et al., 1991; 1995). Along the Oregon, Peru, and Aleutian margins, fluid venting is driven by tectonic compression and compaction of accretionary-prism sediments. Fluid seepage in Monterey Bay, California, may be driven, at least in part, by tectonic compression along transform faults (e.g. Greene et al., 1993, 1994; Orange et al., 1993, 1994; Barry et al., 1996). There is also evidence of active fluid-discharge along faults in the California Borderlands (Lonsdale, 1979; Webb, 1969). With respect to the proposed work, Lonsdale (1979) reported extensive barite deposition and dense colonies of tube worms along a young scarp on the San Clemente Fault Zone (SClFZ)-indicative of active fluid seepage.

Because of its semi-enclosed nature, fluid discharge in the San Clemente basin provides an excellent opportunity to evaluate the impact of cold seeps on geochemical budgets-an opportunity not afforded by other geographically unconstrained systems. Such information is important for extrapolating the relative contribution of cold-seep systems to global geochemical budgets. We propose to test the hypothesis that elemental fluxes associated with fluid seepage at the San Clemente fracture zone influence the geochemical budgets for these elements throughout this basin. Thus to evaluate the impact of cold seeps on geochemical budgets we propose to:

Map the localities and aerial distribution of venting in a geotectonic/structural framework.

Evaluate the rates and composition of fluid discharge.

Quantify cold-seep elemental fluxes and compare them with benthic fluxes on the San Clemente basin floor.

Characterize the mineral deposits associated with the seeps.

The objectives of this proposal fit within the NWNURC programmatic Theme 4: Subduction zone processes and Theme 2: Shelf and slope ecology. Furthermore, the proposed program will complement a NURP program initiative that is addressing issues related to subsurface fluid transport in Monterey Bay, California. Results from the proposed research would constitute a parallel data set to that in Monterey Bay.

Marta Torres - Oregon State University
Geochemical consequences of gas hydrate formation in sediments of the Cascadia accretionary prism

Project Summary: Gas hydrates are solid substances composed of rigid cages of water that enclose molecules of a low molecular-weight gas, mainly methane. Natural gas hydrates occur within seafloor sediments almost everywhere in the world's oceans where water depths exceed 300 m. During gas hydrate formation, methane and water become immobilized as a solid, reducing effective pore space and retarding the migration of fluids. Hydrate-cemented sediments act as a barrier for fluid and gas exchange. Thus, hydrate composition and distribution in the sediments influence hydrologic process within accretionary margins and affect the exchange between sediments and overlying water. Although understanding the biogeochemical processes associated with fluid seepage in continental margins has been identified as an area of scientific priority for undersea research, there is very little information on how geochemical processes in continental boundary sediments may be influenced by hydrate formation and decomposition. The direction of the proposed research is guided by recent discoveries along the Cascadia margin of massive hydrate deposits in near surface sediments; and sites where fresh water and methane gas from hydrate decomposition are discharged at seafloor vents.

Our program is designed to examine: 1) processes that occur above the gas-hydrate sealed strata away from actively venting sites; 2) the mechanisms and consequences of hydrate decomposition at actively venting sites; and 3) the spatial and temporal variability of hydrate decomposition. Specific study sites targeted for this work include locations of known bubble ebullition at the seafloor, locations having massive hydrate blocks located within centimeters of the sediment-water interface, and locations where the hydrate lies under a few meters of sediment cover at non-venting sites our main objective is to assess how near-surface formation and decomposition of a mixed CH4-H2S hydrate in continental margin sediments influences benthic fluxes and early diagenetic reactions at venting sites our main objective is to evaluate the magnitude, and the temporal and spatial variability, of elemental fluxes to the bottom water via hydrate decomposition.

To quantify the exchange of fluids and dissolved constituents from the hydrate field to the overlying water column we propose a multi-investigator program designed to measure this exchange under a variety of conditions within the Cascadia region. We have designed a 2-year field program to deploy benthic devices that can sample fluids and gases at stations ranging from areas characterized by diffusion-controlled transport to sites of advective fluid discharge. We also plan to collect a number of gravity, push and multicores to assess how near-surface formation and decomposition of a mixed CH4-H2S hydrate in continental margin sediments influences benthic fluxes and early diagenetic reactions. The data collected during the first year will be used to assess the spatial variations of constituent release from the hydrate field, variations that are likely to be most significant at active venting sites. These results will allow us to 1) identify ideal sites for temporal variability studies to be conducted during two subsequent visits to the area, and 2) define the length and number of deployments in the following field programs.

The different environments present in the Cascadia margin, along with the spatial-temporal experimental design we propose, will allow us to evaluate the effect of widespread hydrate formation in the Cascadia margin on element mobilization, transport, and release at the seafloor. This knowledge has applications on broader issues in a global scale, as hydrate geochemistry is of significant relevance in global carbon budgets, climate change models, sediment slope stability, and energy resource issues.

Marine Map: Mars Pathfinder 3D Visualization, Control and Analysis Tools for Marine Research

Project Summary: In cooperation with the NASA Ames Research Center, the United States Coast Guard, and Deep Ocean Engineering, the Santa Clara Remote Extreme Environment Mechanisms (SCREEM) lab at Santa Clara University seeks to develop an underwater 3D mapping system for marine research. The proposed research includes using two high-resolution black-and-white cameras mounted for stereo vision on a Deep Ocean Engineering ROV to capture a pair of images that will be "pushed" through the Mars Pathfinder stereo pipeline to create a virtual environment 3D mesh/terrain. Once the terrain is built, MarineMap, a derivative of the highly successful MarsMap program used for the Mars Pathfinder mission, will be used to analyze the 3D models and perform size and volume measurements from within the virtual environment.

As a result of the Arctic and Antarctic Workshop, the US Coast Guard and San ta Clara University developed a marine archaeology mission to the Arctic in search of the sunken 1871 New Bedford Whaling Fleet; Deep Ocean Engineering offered the use of a Phantom XTL vehicle for test use by the Coast Guard; and NASA joined in to both test the 3D image capture technology and ROV operations for future missions. The final product became know as the "Jeremy Project" where Santa Clara University student, Jeremy Bates, would use the Phantom XTL with the stereo vision enhancements and NASA's Mars Pathfinder technology to capture the first vision-based 3D underwater images of one of the sunken ships. This mission hopes to not only further the development of the NASA technology but also help the state of Alaska research the history of the whaling industry in the 1800s.

Sulfide settlement cues in hydrothermal vent environments

Project Summary: One of the most compell ing questions regarding development and maintenance of invertebrate populations in insular environments such as hydrothermal vents, is how dispersal stages locate and recognize suitable habitats. Many organisms recognize specific and highly conservative indicators of these habitats (Rittschof, 1985: 1993). Lutz et al. 1980 and Lutz 1988 suggest that sulfide is an important settlement and colonization cue for vent invertebrates, but to date there has been no systematic test of this hypothesis. A preliminary experiment using diffusional release gels impregnated with sulfide and appropriate controls was undertaken as an ancillary project to a field program funded by NURP in 1995 (C.L. Van Dover, PI). Conducted at Juan de Fuca vents, the experiment demonstrated an active response to sulfide treatments by dispersive juvenile stages of polychaete species (Paralvinella sp.) thought to undergo direct development. These juveniles burrowed into the gels impregnated with sulfide but did not burrow into non-sulfide control gels. In these preliminary experiments, multiple replicate control and experimental treatments were co-deployed for short durations (24-48 h); 20 worms burrowed into the sulfide treatments, non in any of the controls (Rittschof et al, 1997).

We propose to repeat these experiments using modified gel arrays that signif icantly increases the exposure of gel surfaces and simplifies deployment logistics. Van Dover and Chave, co-PIs of an Alvin dive series on Juan de Fuca vents funded by NSF, have sulfide arrays on each of their 6 dives. Additional leverage is a volunteer UK undergraduate who would join the cruise at no cost to the project and would assist with preparation of arrays and post-dive analysis. Results from this work should yield sufficient statistically rigorous data to allow publication in a peer-reviewed journal. More importantly, it will establish the protocol and allow us to return to NURP with a full proposal to study the influence of other chemical cues (e.g. bacterial products, conspecific odors, etc) on settlement processes for the field program in 1999.

Lutz, R.A., D. Jablonski, D.C. Rhoads and R.D. Turner. 1980. larval disp\ rsal of a deep-sea hydrothermal vent bivalve from the Galapagos Rift. Mar. Biol. 57:127-133.

Lutz, R.A. 1988. Dispersal of organisms at deep-sea hydrothermal vents: A review. Oceanol. Acta spec. 23-29.

Rittschof, D. 1995. Oyster drills and the frontiers of chemical ecology: Unsettling ideas. Am. Malacol. Bull. Spec. Ed. No. 1:111-116.

Rittschof, D. 1993. Body odors and neutral-basic peptide mimics: A review of responses by marine organisms. Am. Zool. 33:487-493.

Rittschof, D., R.B. Forward, Jr., G. Cannon, J.M. Welch, M.M. McClary, Jr., E.R. Holm, A.S. Clare, S. Conova, L.M. McKelvey, P. Bryan, and C.L. Van Dover. 1998. Cues and context: larval responses to ph ysical an chemical cues. Biofouling 12(1-3):31-44.

Project Summary: Participation in the 8-26 July ALVIN cruise thanks to Chief Scientists Jim Cowen and H. Paul Johnson may allow me opportunities to make important observations and collections that will further our knowledge of the bioata associated with the dive targets of Baby Bare Seamount and Axial Volcano. Research goals that can be achieved through my participation in this cruise include studies of general fauna of the sea mounts, possible only through collection of specimens and their deposition in collections that allow them to be examined by appropriate taxonomic experts. Specific goals are listed below.

1)Make collections and videotaped observations that will increase our knowledge of the fauna of Baby Bare Seamount, especially octopuses of the genus Granelodone which are very common at the seamount.

2)To examine collected shells of potential octopus prey, including clams and gastropds, for the presence of boreholes. Octopuses are suggested to brood eggs on the seamount because of the high density of avai lable prey (Mottl et al. 1998 Geology 26:51-56). If octopuses, among the few deep-sea predators that are likely to bore the shells of prey, prey heavily on these animals, boreholes in the shells will be few. The alternate hypothesis suggests that octopuses congregate at Baby Bare Seamount because the rock exposures on the seamount offer appropriate egg deposition sites which are rare elsewhere in the North Pacific. Comparing the frequency of exposures with and without brooding octopuses would help test this hypothesis.

3)To establish the developmental stage of the 25 mm long eggs of octopuses of Graneledone compared to their very early developmental stages seen last Oct., roughly 300 days prior. Octopus eggs have a transparent cover which allows embryos to be observed and videotaped. The duration of egg development among deep-sea octopuses in situ remains unknown for all species, although members of the octopus, Bathypolypus, brood their 11 mm long eggs for more than one year at laboratory temperatures near 7.5\260C (Wood et al. 1998 Malacologia 39: 11-19).

4)As possible, preserve any biological collections made at Axial seamount, t he site of a series of January 1998 seismic events. Axial was the collection site for an estimated 46,000 specimens added to Field Museum collections in 1997, material has already been thoroughly examined by graduate students working at FMNH from Dr. Verena Tunnicliffe's laboratory at the University of Victoria. Any additional material collected during this cruise will be made available to these and other workers as soon as possible to ensure maximum information gain from this unique opportunity to study recolonization at North Pacific hydrothermal vents.