GeoHab 2002 Agenda and Abstracts

Agenda

Abstracts

Multibeam Backscatter Comparisons: A Comprehensive Analysis of Comparative Systems and Manufacturers for Water Depths between

6.0 – 6000 meters.

Lockhart, D., Saade, E., and Gilmour, W.

 Thales Geosolutions (Pacific) Inc., San Diego, CA

High-resolution multibeam bathymetric data are now routinely combined with multibeam generated “backscatter” data to support fisheries habitat and related studies worldwide. During the past several years, and in particular during the past 18 months, a variety of multibeam systems have been utilized to conduct these studies. Thales Geosolutions (Pacific), Inc. has conducted surveys using multibeam systems manufactured by both RESON and SIMRAD, operating at frequencies ranging from 12 – 200 kHz, in water depths ranging from 6.0 – 6,000 meters. The purpose of this discussion is to present examples of data products from these applications to better inform the Fisheries Habitat community on the capabilities and limitations of the various sensors at a variety of water depths and discrete frequencies. Data from a variety of worldwide locations are presented. An analysis of actual resolution will be provided as a function of frequency, water depth and vessel speed. In addition, the analysis of a controlled high-resolution side scan sonar vs multibeam backscatter comparison of a 10 sq km section of the seabed will be presented. It is hoped that the information provided herein will allow Fisheries Habitat scientists to better plan and predict the outcome of their studies, and to allow them to attain both the scientific and financial goals.

Laser Line Scan Technology to Characterize Deepwater Habitats and Associated Organisms

Yoklavich, M.¹, Grimes, C.¹, Wakefield, W.W.², and Greene, H.G.³

1) NOAA National Marine Fisheries Service, Southwest Fisheries Science Center, Santa Cruz Laboratory, CA

2) NOAA National Marine Fisheries Service, Northwest Fisheries Science Center, Newport, OR

3) Moss Landing Marine Laboratories, Moss Landing, CA

We conducted a 9-day field test of laser line scan imaging technology (LLS) to characterize and explore benthic habitats in and around the Big Creek Ecological Reserve (BCER) off the central California coast. We are determining the utility of LLS to assess the distribution and abundance of fish, megafaunal invertebrates, and habitats, and comparing LLS images with those acquired from side scan sonar and a remotely operated vehicle. We also are evaluating LLS ability to detect sea floor disturbance caused by fishing trawl gear. We surveyed an area about 2.6 km long and 0.4 km wide inside and directly outside BCER. With the laser we imaged isolated rock outcrops with patches of large Metridium sp. and dense groups of fishes, drift kelp, sea pens, salp chains, and sedentary benthic fishes (possibly California halibut, Pacific electric ray, ratfish, juvenile lingcod, etc.). The LLS system offers the advantage of imaging some of the biogenic components of habitat and describing their spatial relationships with detail that currently is not possible using acoustic techniques such as side scan and multibeam sonar. The LLS system also seemed to do an excellent job at imaging details of the low relief shelf sediments such as sand waves and ripples; evaluating these features in a broader context from a post-processed mosaic of the sea floor could help us understand coastal physical processes that influence dynamic benthic habitats. The development of LLS could improve our understanding of deep-water fish habitats.

Quantitative Sea floor Habitat Classification Using GIS Terrain Analysis: Effects of Data Density, Resolution and Scale

Iampietro, P., and Kvitek, R.

Sea floor Mapping Lab., California State University Monterey Bay, Seaside, CA

There is a great need for accurate, comprehensive maps of sea floor habitat for use in fish stock assessment, marine protected area design, and other resource management pursuits. Recent advances in acoustic remote sensing technology have made it possible to obtain high-resolution (meter to sub-meter) digital elevation models (DEMs) of sea floor bathymetry that can rival or surpass those available for the terrestrial environment. This study attempts to use an algorithmic terrain analysis approach to efficiently, non-subjectively classify sea floor habitats according to quantifiable parameters such as slope, rugosity, and topographic position index (TPI). In addition, we explore the effects of original x,y,z and gridded data density on the results of these analyses, in order to provide insight into how inherent depth-dependent decreases in data density may affect this approach, and to assess the appropriateness of using historical, lower density bathymetric data. Finally, issues of scale with regard to rugosity and TPI are explored and their potential biological relevance discussed.

Subfossil Assemblages in Sediments: a Possible Tool for Mapping Living Biota

Passlow, V.¹, O’Hara, T.², Daniell, J.J.¹

and Beaman, R.J.³

1) Geoscience Australia, GPO Box 378, Canberra ACT 2601, Australia

2) Museum Victoria, GPO Box 66E, Melbourne Vic. 30001 Australia

3) University of Tasmania, GPO Box 252-76, Hobart Tas 7001, Australia

While the study of modern faunas has been used extensively as tool for the interpretation of fossil communities, there has been little investigation of the potential for subfossil data to be used as a tool for the prediction either of modern faunas or their links to geological parameters.

The material used in this work comes from a study of Bass Strait, carried out as a series of surveys in the period 1979-1983 (Wilson & Poore, 1987). Bass Strait forms a narrow seaway between mainland Australia and the island of Tasmania. The Bass Strait Study was aimed at the description of biological species in the area and remains the most comprehensive collection of marine invertebrates from the region. Sediment samples were also obtained as part of the original study, providing an opportunity to examine links between sediments and biota in the region.

On a general level, there are issues with the interpretation of subfossil data. Not all biota leave hard parts. Not all hard parts are readily preserved. In addition, post-mortem processes can affect the record of biota. Some of these limitations are evident in this study. Because of the nature of Bass Strait and its geology, many of the sediments are composed of a mix of recent and older, palimpsest material. While a high level of diversity is evident in the subfossil material, the biological data indicates that the greatest abundance occurs in groups which leave little or no fossil record.

Statistical analysis of the biota (O’Hara, 2002) showed little evidence of distribution patterns related to sediment at the scale of the study. At a more detailed level, the most abundant and potentially most useful of the subfossil groups appears to be bryozoans (lace corals). Bryozoans are one of the main sediment-producing organisms in the cool-water carbonate sediments of southern Australia. In the Bass Strait material distinct morphological types show distribution patterns which appear to be linked to sediment characteristics. The Bass Strait material suggests that the ability of the subfossil component to predict living fauna is a question both of scale and of the make-up of communities. On a more detailed level, bryozoa potentially provide data linking fauna and sediments. Sites to the east of Bass Strait, which have been studied more recently using a variety of techniques, including video and swath mapping, are providing an additional test of this approach.

References:

O’Hara, T., 2002. Benthic Assemblages of Bass Strait. Museum Victoria Report to Geoscience Australia. 39pp.

Wilson, R.S. & Poore, G.C.B. (1987). The Bass Strait Survey: biological sampling stations, 1979-1984. Occasional Papers from the Museum of Victoria 3: 1-14.

SUSHIMAP – Survey Strategy and Methodology

for Marine Habitat Mapping

Fossaa, J.H.¹, Alvsvaag, J.¹, Thorsnes, T.², and Christensen, O.³

1) Institute of Marine Research, Bergen, Norway

2) Norwegian Geological Survey, Trondheim, Norway

3) Norwegian University of Science and Technology

The project aims to develop a rapid, reliable and cost-efficient procedure for the mapping and monitoring of seabed habitats. The procedure integrates medium- and fine-scale data from visual and sediment-grab methods with large-scale bathymetric and backscatter data obtained by multibeam echo sounding. With the help of this procedure, SUSHIMAP will define a long-term plan for monitoring of marine habitats. Preliminary results from the sampling of fauna and seabed properties, as well as examples of integration and visualization of data and information from the multiple sources, are reported.

Seabed Biotope Surveys in Deep Water using Remote Sensing – Needs and Realities

Kloser, R., Williams, A., and Butler, A.

CSIRO Marine Research, Castray Esplanade, Hobart,

Tasmania 7000 Australia

This paper outlines a strategy for optimised deep seabed mapping using a combination of tools (multibeam and single beam acoustics, video, various direct samplers, and data from other sources). We focus on the management needs for seabed biotope mapping in the Australian context and its multi-disciplinary nature. We stress the habitat attributes relevant to the scale of impact of human activities and to the scale of management (not necessarily the same things), and we consider issues for monitoring using modern technology. The paper outlines the strengths and weaknesses of the equipment and methodologies employed so far. In particular, we give examples to highlight the realities of sampling and the need for caution with automated methods given current classification techniques for video and acoustics.

Mapping the Geology of the Monterey Bay Area Sea floor at High Resolution and what it reveals of Shelf Benthic Habitats

Eittreim, S.L., Anima, R.J., and Edwards, B.D.

U.S. Geological Survey, Menlo Park, CA 94025

Recently completed sonar mapping of the greater Monterey Bay offshore area by U.S. Geological Survey (USGS) scientists provides 100% sonar coverage for more than 100-km of the Continental Shelf from Año Nuevo to Pt Sur. Sonographs with one meter pixel resolution north of Monterey Canyon, and 2.5-m pixel resolution south of the Canyon, combined with seismic-reflection profiles and hundreds of sea floor samples, provide unprecedented detail for understanding sea floor characteristics that produce the physical traits of benthic habitats over this large area. Additional cooperative work between geologists and benthic biologists is needed to fully exploit this database.

North of Monterey Canyon, bedrock outcrops occur on parts of the inner and outer shelf, with a mid-shelf Holocene mud belt in between. This outcrop pattern is a product of the uplifting highlands of the Santa Cruz mountains, the 100-m sea level rise over the past 15,000 years, and the supply of sediment to the shelf from the three rivers entering Monterey Bay (San Lorenzo, Pajaro, and Salinas Rivers). The outcrops are generally elongated NW-SE, are produced by the outcrop of dipping beds that are resistant to erosion, and range from layered and blocky to rounded rubble piles. The sonographs, combined with high-resolution seismic-reflection profiles, reveal both the vertical and horizontal scales of outcrop as well as document the patchiness (or connectivity) of outcrop. Each of these three characteristics of sea floor geology can be crucial to the health of various benthic and demersal species.

These data sets include six areas of the continental shelf proposed by the State of California as Marine Protected Areas (MPAs) within the Monterey Bay National Marine Sanctuary. Three of the six proposed MPAs encompass outer-shelf substrate composed of varying amounts of modern fine-grained sediment, of low relief, layered-rock outcrops, of higher relief, and coarse rippled-sand deposits. Do geologic considerations support the selection of these locales as MPAs based on biologic data? The variation of bottom types observed throughout these inner-and outer-shelf environments, suggests a comparable diversity of biota over these regions.

Acoustic Mapping of Sponge Reefs in the Pacific Northwest

Conway, K.W. ¹, Barrie, J.V.¹, Krautter, M.², and Neuweiler, M.²

1) Pacific Division, Geological Survey of Canada

2) University of Stuttgart, Germany, Institute of Geology and Paleontology

Recent mapping of siliceous sponge reefs on the continental shelf of western Canada has been accomplished by a variety of acoustic methods. The hexactinellid sponge reefs were first discovered during surveys employing sidescan sonar and sub-bottom profiling systems in the mid 1980s. High resolution, deep towed, single channel seismic (Huntec Deep-Tow), conventional hull mounted profilers (3.5 and 12 kHz) various sidescan sonar instruments (Klein, EGG and Simrad) and a multibeam swath bathymetry system (Simrad EM 1002) have all now been used to map sponge reef distribution. Four extensive sponge reef complexes, covering 700 km², have been identified in Queen Charlotte Basin (QCB) and one smaller reef complex has recently been discovered in the Georgia Basin (GB). The acoustic signature of these features, which can attain heights of 19 m in the QCB, is distinctive and readily identified. The reefs develop from the coalescence of small mud mounds that grow to form steep-sided bioherms and aerially extensive biostromes, over millennia. The non-reflective acoustic properties of the reefs are mainly due to the massive clay matrix sediments, the framework of buried siliceous sponge skeletons, and the surface covering of living sponges. These characteristics provide a sharp acoustic contrast with the normally reflective and dense underlying relict glacial sediments, which are characterized by gravel to boulder size and glacial marine clays that have been iceberg scoured. At some sites sponge reefs with higher relative surface reflectivity are thought to be “dead” while in other areas sponge bioherms that have been subject to trawling by fishing vessels are readily mapped with sidescan sonar. Given that the frame building and reef forming Hexactinosan sponge species that create the reefs are found throughout the north Pacific it is possible that undiscovered sponge reefs exist on the deep continental shelves of Alaska and Russia.

The use of Geological Data in Developing a Framework for the Mapping of Marine Habitats on a National Scale in English waters

James, J.W.C.¹, Poulton, C.¹, Philpott, S.¹, Graham, C.²,

Bee, E.¹, and Jones, L.³

1) British Geological Survey, Keyworth, Nottingham, U.K.

2) British Geological Survey, West Mains Road, Edinburgh, U.K.

3) English Nature, Peterborough, U.K.

European legislation with regard to both marine and terrestrial habitats is producing a demand for facts and data so that national governments and conservation agencies can respond, in a constructive and informed manner, to their obligations under the legislation. Included within these are the designation of conservation areas and the mapping of specific marine habitats. These are for national coverage.

To meet the criteria for national coverage with English waters the only dataset available, apart from bathymetric charts, are 1:250,000 geological maps and survey data published and acquired by the British Geological Survey. The themes of these maps are seabed sediments, Quaternary Geology and Solid Geology. The seabed sediments map has been used as the main geological dataset in developing a framework for the mapping of marine habitats, with the Quaternary and Solid geology feeding complimentary data. A seabed features dataset has been created using ArcView as the GIS with attributed polygons linked to an Access database.

The sea bed features GIS is the primary dataset but this is complimented by a bio-feature dataset and bedform feature dataset based on criteria within the European Union Habitats Directive for mapping features such as sand banks, reefs, caves and gas escape features.

The project is a first step in meeting the demands of European legislation. It will require review when completed, in considering how far currently available data can be used to adequately map marine habitats in response to environmental and legislative pressure.

MAREANO – a Proposed Integrated Study of the Mid-Norwegian Shelf and Slope – Focusing on Multibeam Technology,

Geology, Habitat Mapping and Pollution

Thorsnes, T.¹, Fossaa, J.H.², and Olsen, K.³

1) Geological Survey of Norway

2) Institute of Marine Research, Norway

3) Norwegian Hydrographic Service

An initiative is currently being taken by several Norwegian organizations to obtain funds to intensify ongoing investigations on marine sea-floor mapping off Norway. Led by the Geological Survey of Norway, the Institute of Marine Research and the Norwegian Hydrographic Service, planning during the last years has led to the inception of a large-scale mapping project entitled “MAREANO - Marine Areal Database for the Norwegian Sea”. The proposed investigation area covers 270 000 km² of the shelf and deep sea off the central part of western Norway. If funded, the project period is planned to 2003-2007. It is a commercially important region for fisheries and the petroleum industry and includes the world’s largest system of cold-water coral reefs. The aim of MAREANO is to collect new as well as historical data elucidating the physical, chemical and biological characteristics of the seabed along the mid-Norwegian shelf and parts of the deeper Norwegian Sea. The project shall produce a comprehensive database on seabed bathymetry, marine habitats, biological diversity and resources, mineralogical resources and geological features as well as habitat contamination. Stored in a GIS database, this information shall be available to environmental managers and interest groups as well as the fisheries, aquaculture and petroleum industries via a dedicated system on the Internet.

Mapping Marine Benthic Habitat in the Gulf of Alaska: Biological Communities, Geological Habitat and Fishing Intensity

Heifetz, Jonathan¹, Courtney, Dean L.¹, Fujioka, Jeffrey T.¹, Greene, H. Gary ², Malecha, Patrick¹, and Stone, Robert P.¹

1) National Marine Fisheries Service, Auke Bay Lab, 11305 Glacier Highway, Juneau, AK 99801

2) Moss Landing Marine Lab, 8272 Moss Landing Road, Moss Landing, CA 95039

During summer 2001 multibeam, backscatter, and video data were collected on the Portlock Bank area of the central Gulf of Alaska in the vicinity of extensive bottom trawl and longline fisheries for groundfish. The objective of the study was to characterize bottom habitat in or near heavily fished grounds to understand whether habitats in current fishing grounds are vulnerable to ongoing fishing activities. The area mapped was about 1000 km² of the outer continental shelf and upper continental slope. Preliminary interpretations of multibeam and backscatter data indicate the presence of at least a dozen different benthic macro- or meso-habitats. The megahabitats of this area are distinctly the result of past glaciation with the glacial deposits presently being reworked and shaped into moderate (cm-m) relief features. Many submarine canyons notch the upper slope and provide steep relief with alternating mud-covered and consolidated sediment exposures. From the video data collected from the research submersible Delta, there was little evidence of trawling on the flatter grounds of the continental shelf where perhaps the relatively level bottom did not induce door gouging and there is a lack of boulders to be turned over or dragged. The most common sessile epifauna were crinoids, small non-burrowing sea anemones, glass sponges, stylasterid corals and two species of brittlestars. Occasional large boulders were located in depressions were the only anomaly in the otherwise flat sea floor. These depressions may have afforded some protection to fishing gear, as the glass sponges and stylasterid corals attached to these boulders were larger than were typically observed. In the fished areas of the upper slope, there was evidence of boulders turned over or dragged by trawling. The uneven bottom perhaps induced gouging by the trawl doors. The substrate was mostly small boulders, cobble, and gravel. Presently there does not appear to be much habitat in this habitat that can be damaged by trawl impacts. No large corals and very few large sponges were seen. Whether this is the result of past trawl activity is unclear.

Mapping Seabed Habitat & Biodiversity for Ecological Risk Assessment and Conservation Planning

Pitcher C.R., Venables, W., Pantus, F., Ellis, N., McLeod, I., Austin, M.,

Wassenberg, T.,Skewes, T., Gordon, S., and Smith, G.

CSIRO Marine Research, PO Box 120, Cleveland, Qld. 4163, Australia

The current lack of knowledge of biodiversity living on the open continental shelf seabeds makes conservation planning and management for sustainability in these areas a difficult and largely subjective task. Without this knowledge, it can also be difficult to justify management actions to stakeholders. It is therefore imperative that rigorous inventories of seabed biodiversity distribution & abundance are conducted to develop a reliable and effective baseline for conservation and management, including systems of highly protected areas (HPAs) justifiable on sound biological data. Selection of truly comprehensive, adequate and representative (CAR) candidate areas (CAs) is ultimately dependent on achieving such inventories, as is quantitative ecological risk assessment of human activities in the marine environment.

We report on progress with projects conducting habitat and biodiversity surveys on tropical shelf seabeds. Multiple survey devices are used, including: eg. acoustics, towed video, epibenthic sled, trawl. Biological sampling is necessary to deliver a sound scientific baseline and establish reference inventories of the constituent biota, using appropriate collections of voucher samples to authenticate species-level biodiversity. Having this baseline biodiversity reference enables rigorous testing of the performance of "rapid assessment" techniques (e.g., acoustics, video) – how well do they discriminate patterns in species biodiversity? Survey cost and amount of direct sampling is minimized by using environmental covariates and biophysical relationships to develop informed stratifications and predict biota in unsampled areas within strata. These approaches lead to the most efficient design for sampling a diversity of biotopes on the seabed, and combine state-of-the-art modelling to interpolate these data to habitats with the same biophysical characteristics.

Applications of this information include: identification of representative areas from which HPAs can be selected; assessment and performance review of marine reserve systems; identification of gaps in the coverage of biodiversity; development of indicators of the status of biodiversity in relation to sustainable/risk management of multiple-uses; and evaluation of alternative strategies for managing human use to deliver environmental goals.

Grasping the Thorny Issues of Marine Habitat Classification for Marine Habitat Mapping

Cogan, Christopher B.¹, and Wright, Nancy ²

1) Alfred Wegener Institute for Polar and Marine Research, Bremerhaven Germany

2) California Department of Fish and Game, Marine Region, Monterey California USA

There are many issues of marine ecology that should be based upon a unified concept of habitat types and communities, and therefore, ecological classification. Whereas previous research relied on point data sources and available themes (e.g. fisheries catch data), we will increasingly require quantitative interdisciplinary descriptors of broad-based biodiversity. The classification of ecological habitat types is of fundamental importance to a suite of marine issues including the assessments of coastal zone management areas, marine protected areas (MPA’s), environmental quality reports, environmental degradation analysis, toxic spill response planning, fisheries management, ocean aquaculture, and long-term ecosystem health issues such as El Niño and global warming. Each of these research topics considers marine habitat types and communities as fundamental elements of the ecosystem. If our conceptual model of these ecological units is in error, or if it varies implicitly within elements of multidisciplinary research, the products of our research are likely to be flawed, or at best inadequate.

In this paper we identify several existing habitat classification schemes, and discuss how each is specialized for particular goals. For each system the implicit and explicit classification system is explored to better understand how model bias can influence our perception of marine systems. We suggest methods to more closely integrate existing models, which will be needed if we are to provide researchers and applied management with a framework for habitat-type mapping and improved marine management.

Keywords: MPA, marine reserves, marine habitat classification, management areas, biodiversity, geographic information systems (GIS).

A GIS Attribute Code for Deep-Water Marine Habitat Characterization: Work in Progress

Greene¹, H. Gary, Yoklavich², M.M., O’Connell³, V.E.,

and Bizzarro¹, Joseph J.

1) Moss Landing Marine Laboratories, Center for Habitat Studies, Moss Landing, CA USA

2) National Marine Fisheries Service, NOAA, Santa Cruz, CA USA

3) Alaska Department of Fish and Game, Sitka, AK USA

Deep-water benthic habitat mapping is accelerating in scope and importance as remote sensing technologies, access to the sea floor, and concern for human impacts on fisheries and sea floor biota increase. With this increase in mapping effort and the use of GIS techniques, many different types of maps and various methods of habitat classification are being developed. To easily distinguish marine benthic habitats and to facilitate ease of use and queries with GIS and database programs, a habitat attribute code, based on the deep-water habitat characterization scheme developed by Greene et al. (1999), is presented. This scheme is hierarchical, can be used to compare and contrast marine benthic habitat types in a standard manner, and is divided into the following categories: System (marine benthic), Subsystem (based on physiography and depth), Class (based on sea floor morphology), Subclass (based on substratum texture and slope), and Modifiers (for bottom morphology, bottom deposition, bottom texture, physical processes, chemical processes, and biology). To reflect this classification in GIS and database programs, we have developed a two-part code. The following categories apply directly to habitat interpretations determined from remote sensing imagery (for mapping of study areas at the scale of 10s of km to 1 m): Megahabitat (based on physiography and size related, features larger than 10 km), Bottom Induration (based on substrate hardness), Meso/Macrohabitat (size-related, from 1 km to 1 m), Modifier (textural and lithologic relationship), Slope, and Sea floor complexity. Additional categories apply to smaller scale areas (10 m to cm) and are either determined from video, still photos, or direct observations: Macro/Microhabitat (size-related, from 10 m to cm), Modifiers (geologic and biologic), Slope, and Sea floor complexity. These categories can be used in conjunction to define a habitat across spatial scales or separately for comparisons between large and small-scale habitat types. Although the code appears complex, it is not necessary that all components be used and the code can be simplified and tailored for individual preferences. This scheme is a work in progress and we welcome input on how it can be improved and made more useful to a larger community of scientists, managers, and policy makers. A draft copy of the scheme and code with explanation is included as an appendix to this abstract volume for your use and comments.

Greene, H.G., Yoklavich, M.M., Starr, R.M., O'Connell, V.M., Wakefield, W.W., Sullivan, D.E., McRea, J.E., and Cailliet, G.M. 1999. A classification scheme for deep sea floor habitats. Oceanologica Acta. Vol. 22 (6): 663-678.

Automated Seabed Classification for Habitat Assessment –

Preliminary Results from Studies of Submerged Aquatic Vegetation in Puget Sound, WA

McGee, Richard¹, Tear, Lucinda M.¹, and Bergersen, Douglas²

1) Parametrix Inc., Kirkland, WA.

2) Triton Elics Int., Watsonville, CA

This presentation examines the preliminary results from an automated approach to seabed classification conducted for the purpose of habitat assessment. The area of study is a portion of Puget Sound, WA. Automated seabed classification was conducted on a mosaic of the sidescan sonar imagery acquired across the seabed. The classification scheme is based around a statistical analysis of a gray-level co-occurrence matrix. Boundaries of seabed types produced from the classification algorithms were analyzed in relation to the mosaicked imagery from which they were produced and in relation to other information describing the habitats of the survey area. Based on the results from this survey area we believe this sort of approach for analyzing seabed data can play an important role in habitat assessment but perhaps more importantly habitat monitoring.

A Regional Approach to Marine Sublittoral Habitat Classification: An Example for Northeastern North America

Valentine, Page C.¹, Todd, Brian J.², and Kostylev, Vladimir E.²

1) U.S. Geological Survey, 384 Woods Hole Road, Woods Hole,

MA 02543

2) Geological Survey of Canada (Atlantic), 1 Challenger Drive, PO Box 1006, Dartmouth, NS B2Y 4A2

Habitats can be defined as spatially recognizable areas where the physical, chemical, and biological environment is distinctly different from surrounding environments. Implicit in this definition is the question of scale. Conceivably, a habitat can be defined as narrowly or as broadly as the data and the purpose permit, and this flexibility of scale necessarily influences the development of habitat classification schemes.

Several recent habitat classification proposals have focused on a wide range of habitats that occur in European land and water environments;¹ United States marine and estuarine environments;² and worldwide deep (subtidal) sea floor environments.³ These classifications define the marine sublittoral zone as lying below the intertidal zone and extending to the continental shelf edge at a water depth of approximately 200 m. The classification scheme proposed here is based on recent observations in the Gulf of Maine using multibeam and sidescan sonar surveys, video and photo transects, and sediment and biological sampling. The marine sublittoral in this region includes continental shelf basins that reach depths of approximately 400 m and submarine canyon heads that incise the continental shelf and reach depths of up to 800 m.

The goal of the proposed classification is to develop a practical method to characterize the marine sublittoral habitats of the northeastern North America region not just in terms of (1) their geological, biological, and oceanographic attributes, but also in terms of (2) the natural and anthropogenic processes that affect the habitats. The classification scheme is a four level hierarchy in which the three higher levels, classes (see table) and subclasses and categories (not shown), are applicable worldwide, while the lowest level (attributes, not shown), describes regional habitat characteristics. Classes 7 and 8 are included to address the growing importance of habitat information to the management of fisheries and environments. This approach to habitat classification is applicable also to regions outside of the Gulf of Maine.

Class 1 addresses the water depth and topographic setting of habitats in terms of photic/aphotic zones, depth intervals and physiographic features.

Class 2 addresses the movement and stability of seabed materials in terms of current type, strength, and frequency of movement.

Class 3 describes the texture and relative hardness of the seabed by using texture analysis and visual observations of seabed character.

Class 4 describes the physical and biological roughness of the seabed in terms of bedforms, shell deposits, burrows, epifauna, and gravel piles and other features smaller than those treated in Category 1.

Class 5 describes seabed chemistry in terms of carbon content and depth of oxidation, among others.

Class 6 addresses properties of water masses that affect habitats such as temperature, salinity, upwelling, and productivity, among others.

Class 7 describes the habitat in terms of faunal usage such as spawning, juvenile survival, and essential fish habitat, and in terms of human activities that affect the seabed.

Class 8 describes the recovery time of physical and biological characteristics of habitats from fishing and natural disturbances.

Class 9 enumerates the dominant and typical biological elements that characterize habitats.

The classification is expandable at all levels and into all regions and habitats. It serves as a template for a database, thus providing a convenient method for organizing and comparing habitat information. As new observations are made, new attributes can be added to the classification scheme. As regional classifications increase in complexity, it will be possible to compare habitats of different regions and to merge them if that proves useful.

1. EUNIS (European Nature Information System) Habitat Classification, Version 2.2, May, 2001: European Environment Agency (EEA), http://mrw.wallonie.be/dgrne/sibw/EUNIS/.

2. Allee, R.J., and others, 2000, Marine and estuarine ecosystem and habitat classification: National Oceanic and Atmospheric Administration, NOAA Technical Memorandum NMFS-F/SPO-43, 43 p.

3. Greene, H.G., and others, 1999, A classification scheme for deep sea floor habitats: Oceanologica Acta, v. 22, no. 6, p. 663-678.

Habitat Mapping of Sites of Conservation Importance (SCIs) around the Azores Islands for Management Purposes

Santos, Ricardo Serrao, Tempera, Fernando, Cardigos, Frederico

and Salgado, Madalena

IMAR, Dept. of Oceanography & Fisheries, University of the Azores, PT-9901-862, Horta, Portugal

The description of hydrothermal vents ecosystems is of interest both to ecological studies and nature conservation management of these unusual environments. In D. João de Castro offshore bank (Azores, Portugal), one of the sites designated as a Special Area for Conservation (Natura 2000 network), hydrothermal activity is a frequent feature between -13 and 45m deep. Under EU-MAST III project ASIMOV, several methods and technologies have been brought together to study the habitats and biological communities in the area. Side-scan, Doppler and echo-sounder units were used to draw geo-referenced 3-D maps that include the positioning, intensity and density of venting activity. The maps produced show that the venting activity concentrates in the northeastern part of the volcanic cone.

Imaging (photo and video) tools operated by UW-scooter-powered scuba divers have been employed to survey the bottom topography and identify conspicuous epibenthic species. The communities are mainly divided in three groups: sandy, rocky and rocky with venting activity. Sandy communities below –40 metres are species-poor. The rocky habitats between –20 to –45 metres are dominated by an algal mosaic of Sargassum sp., Coralina sp. and Halopteris sp. in the shallower area, and Zonaria tournefortii in the deeper zones. The communities on rocky substrata near vents are dominated by filamentous thermophyle bacteria and a dense mosaic of different algae (e.g., Cladostephus spongiosus, Codium elisabethae and Padina pavonica).

Water sampling along the water column allowed large-scale surveys of methane plumes (indicator of hydrothermal activity). The data collected with the later technique suggest the occurrence of hydrothermal activity at depths ranging between -150 and -250m. Hydrothermal fields at such depths are poorly known and D. João de Castro should be a suitable site for the development of future studies that make use of Remotely Operated Vehicles (ROVs) and Autonomous Underwater Vehicles (AUVs).

Small-Scale Analysis of Subtidal Fish Guilds and Associated Habitat Characteristics along Central California

Field, Jeffrey M.¹, Yoklavich, Mary M.², Cailliet, Gregor M.¹, Bros, Shannon³, de Marignac, Jean¹, and Lea, Robert N.⁴

1) Moss Landing Marine Laboratories, 8272 Moss Landing Rd.,

Moss Landing, CA 95039

2) NOAA National Marine Fisheries Service Southwest Fisheries Science Center Santa Cruz Laboratory, CA

3) San Jose State University, San Jose, CA

4) California Dept. of Fish and Game, Monterey, CA

Recent declines in fish populations are prompting revisions and alterations to current fishery management policies. One alternative is the establishment of Marine Protected Areas (MPAs) to promote the recovery of fish stocks. However, before MPAs can be created, habitat associations of the fishes designated for protection need to be characterized to ensure that the ideal habitat can be included when MPAs are designated. Once the habitat associations of each species are known, remote sensing technology, such as side scan sonar, can be used to survey large-scale areas to identify potential habitat for MPAs.

In the Eastern Temperate Pacific, rockfishes (Sebastes spp.) are slow growing, have a late age-at-maturity and specific habitat affinities. These life history characteristics make them especially susceptible to fishing pressure and ideal candidates for protection through MPAs. To assess habitat associations of fishes within the Big Creek Ecological Reserve, Central California, we conducted submersible dives to identify habitat at the meter scale and to quantify fish populations. Multivariate statistical analysis revealed distinct habitat associations for several rockfish species. In addition, distinct sea floor features were identified as unique habitats at the meter scale.

The role of Geoscience in the Development of Australia’s

Southeast Regional Marine Plan

Harris, P.T.¹, Heap, A.D.², Passlow, V.³, Porter-Smith, R.¹,

Fellows, M.³, and Daniell, J.³

1) Geoscience Australia and Antarctic CRC, GPO Box 252-80, Hobart TAS 7001, Australia

2) Geoscience Australia, School of Geography and Environmental Studies, University of Tasmania, GPO Box 252-78, Hobart TAS 7001, Australia

3) Geoscience Australia, GPO Box 378, Canberra ACT 2601, Australia

Ecosystem-based management via regional marine planning is a central policy principle of Australia’s Oceans Policy, and the National Oceans Office is charged with putting regional marine planning into effect. An assessment of the geology and geomorphology of Australia's southeast region was carried out by Geoscience Australia in order to contribute to the derivation of a bioregionalisation that will provide a framework for ecosystem-based management of the region.

The bioregionalisation is a hierarchically structured system containing higher level 1 Provinces (>1,000 km in extent) and level 2 Biomes (several 100s km in extent), distinguished primarily based on the distribution of demersal fish species, but corroborated with data on tectonic elements, fault-lines and plate age. At the third level of this hierarchy are major meso-scale geomorphological units (~100 km in extent) characterised by similar geomorphology. A key point is that information at a lower level in the hierarchy was needed in order to locate higher level boundaries in each case (i.e. data mapped at the scale of level 3 was used to locate level 2 boundaries, etc.). Geological and modeled oceanographic data proved to be the only systematically collected (and therefore mappable) information available at levels 3 and 4 within the hierarchically structured system that we used.

The geomorphological units that we mapped on the slope and at abyssal depths were submarine canyons, saddles, plateau, continental blocks, seamounts, abyssal plains, oceanic ridges and troughs. Such units are typically about 100 km in extent. Geomorphological units are inferred to be associated with distinct biotic assemblages, which justifies their utilisation in the derivation of a bioregionalisation, although it is recognised that our reliance on purely physical data to map essentially biological units is a weakness in our analysis. A bathymetric data set grided at 250m was used with reference to previously published work to derive a map of the distribution of geomorphic units in the southeast region deeper than the continental shelf. The identification of individual submarine canyons was aided by using the results of a drainage analysis of the bathymetric model (including the 250m grid AUSLIG topographic map for Australia) carried out using ARCINFO. Patterns identified from the geological structure were corroborated by examining maps of crustal age, seabed sediment type, sedimentary basins, acoustic facies and modeled ocean current speed and direction (both mean and maximum). In some cases, the geomorphic units were further subdivided on the basis of patterns suggested by these corroborative data sets, particularly the acoustic facies maps.

Moving toward Ecosystem-based Management - an Interim Bioregionalisation for the Southeast Marine Region of Australia

Hall, M., Davies, C., Deese, H., and Musso, B.

National Oceans Office, GPO Box 2139, Hobart, Tasmania 7001, Australia

Under the United Nations Convention on the Law of the Sea, Australia has sovereign rights to explore, exploit, conserve and manage the natural resources within one of the largest Exclusive Economic Zones in the world. Australia’s Oceans Policy provides a framework to fulfill our responsibilities of protection and ecologically sustainable management of our ocean jurisdictions. The National Oceans Office is responsible for leading the implementation of the policy through the development of Regional Marine Plans and coordination of other initiatives under the Policy. The first regional marine plan is being developed for the South-east Marine Region (SEMR), which includes three Large Marine Domains (Southeast, South Tasman Rise, Macquarie) and covers over 2 million square kilometres of Australia’s Marine Jurisdiction. Policy principles that guide the development of regional marine plans include ecosystem-based management and outcome-based planning. This paper describes how these policy principles have guided the development of the Interim Bioregionalisation for the South-east Marine Region and a process for using the Bioregionalisation in development of ecologically based planning units for regional marine planning.

Habitat Associations of Upper Slope Rockfishes (Sebastes spp.)

and Co-occurring Demersal Fishes in the Headward part

of Ascension Canyon California

Bizzarro, Joseph J.¹, Field, Jeffrey M. ¹, Greene, H. Gary¹,

and Lea, Robert N.²

1) Center For Habitat Studies, Moss Landing Marine Laboratories, 7544 Sandholt Road, Moss Landing, CA 950939

2) California Dept. of Fish and Game, 20 Lower Ragsdale Road, Monterey, CA 93940

Due to their typical life history patterns (slow growth, late age at maturity, extreme longevity) deep-water rockfishes (Sebastes spp.) are especially susceptible to overfishing, as evidenced by recent declines in most commercially targeted stocks. To establish effective Marine Protected Areas (MPAs), the interaction between fishes and their available habitats must be determined. Our objectives were to describe habitat associations for upper slope rockfishes and co-occurring fish species within the headward part of Ascension Canyon at both large (1 to 10s of kilometers) and small (10s to 100s of meters) scales. Geologic structure and lithology were investigated using high-resolution multibeam bathymetric and backscatter data. These data were interpreted to produce habitat maps of the study areas. Sea floor features and fish assemblages were then surveyed using the Delta submersible 50 meter intervals between 200 and 350 meters. Thirty-two ten minute transects were completed between two distinct, large-scale habitat types. At 200 and 250 meters, stripetail (Sebastes saxicola) and greenstriped (S. elongatus) rockfishes were the dominant fish species. At 300 and 350 meters, splitnose (S. diploproa) and shortspine thornyhead (Sebastolobus alascanus) were the most abundant rockfishes. Large and small-scale habitat associations of these and several other commercially important demersal fishes were also determined.

Habitat Mapping with a Direct Application to

Commercial Fisheries Management

 O’Connell, V.M.¹, Greene, H.G.², Brylinsky, C.¹, Bizzarro, Joseph J.², Wakefield, W.W.³, and Carlile, D.⁴

1) Alaska Department of Fish and Game, Commercial Fisheries Division, Sitka, Alaska

2) Moss Landing Marine Laboratory, Center for Habitat Studies, Moss Landing, California

3) National Marine Fisheries Service, Northwest Fisheries Science Center, Newport, Oregon

4) Alaska Department of Fish and Game, Commercial Fisheries Division, Douglas, Alaska

The Alaska Department of Fish and Game (ADF&G) is using geophysical techniques to classify marine fish habitats for use in stock assessment of Demersal Shelf Rockfishes or DSR (Scorpaenidae: Sebastes). DSR are the target of an important shore-based fishery in the eastern Gulf of Alaska (330 mt allowable catch). These fishes are difficult to assess using traditional techniques as they are closely associated with complex rocky habitats. We have been using an occupied submersible to conduct line transects for estimating density of DSR since 1990. Biomass is derived as the product of estimated density (for all rocky habitats), the estimate of area of suitable habitat within the 200 m contour, and average weight of fish from port samples by management area. The greatest uncertainty in this approach is the estimate of rock habitat. Previously the estimate of area of suitable habitat was based solely on the habitat description from U.S. NOAA National Ocean Service navigation/bathymetric charts -- sea floor classification in these charts is very limited.

 To improve our delineation of available habitat, we conducted a series of sidescan sonar surveys to identify areas of key habitat types in several important fishing grounds in Southeast Alaska. The first survey resulted in a large mosaic encompassing 563 km² of the sea floor off Kruzof Island, approximately one fourth of the estimated DSR habitat in the CSEO management area. The area is diverse in habitat, including areas of plutonic rock outcrop, boulders, gravel or pebble, and sand, plus an extended area of lava flows. These habitat characterizations have been groundtruthed with direct observations from a submersible. 304 km² of this area is classified as rocky.

We conducted a sidescan sonar survey on the Fairweather Ground in August of 1998. The area surveyed was 780 km² of sea floor, primarily on the western bank of Fairweather. In the area sidescanned, 452 km² was rocky. Although the area surveyed did not cover the entire Fairweather Ground, it is possible to compare techniques by evaluating the difference between the west bank polygon we thought was rock in 1998 (279 km² in this polygon) to the sidescan data that documents 218 km² of rock habitat within that polygon. The sidescan data in conjunction with NOS data, submersible dives, and logbook data were used to re-estimate rock habitat for the EYKT area, now estimated at 617 km².

 Multibeam bathymetric and backscatter data were collected for a portion of the CSEO and SSEO sections in the summer of 2001. These data have not yet been fully analyzed but preliminary review yields an estimate of 223 km² of rock habitat. To date we have mapped over 2000 square kilometers of sea floor. This represents 7% of the total habitat inside the 100 fm contour along the outer coast of Southeast. More importantly, we have mapped 980km² of rocky habitat, approximately 32% of what is estimated to occur. Ultimately, our ocean mapping efforts will provide a permanent record of the sea floor for use in the management of living resources within the region.

Mapping the Gulf of Maine: Building the Link between Marine Geology and Benthic Habitats to Improve Ocean Management

Todd, Brian J.¹, Pickrill, Richard A.¹, Valentine, Page C. ²,

Snow-Cotter, Susan³, and Noji, Thomas⁴

1) Geological Survey of Canada (Atlantic), P.O. Box 1006, Dartmouth, Nova Scotia, B2Y 4A2, Canada

2) US Geological Survey, 384 Woods Hole Road, Woods Hole,

MA 02543

3) Massachusetts Office of Coastal Zone Management, 251 Causeway Street, Suite 900, Boston

4) National Marine Fisheries Service, James J. Howard Marine Sciences Lab, 74 Magruder Road, Highlands, New Jersey 07732

Multibeam sea floor mapping technologies have provided the capability to accurately, and cost effectively, image large areas of the seabed. This imagery provides base maps of sea floor topography and seabed reflectivity from which targeted surveys can be planned to characterize sea floor sediments and associated benthic communities. Integrated mapping programs have been developed to minimize ship survey time and to generate accurate maps.

Over the last decade extensive multidisciplinary surveys have been carried out in the Gulf of Maine on Stellwagen, Browns, German and Georges banks. Maps produced show bathymetry, surficial sediments and benthic communities. Scientific results have been published through normal peer review channels, but probably of far greater immediate impact has been the use of this knowledge by the commercial fishing industry and by fisheries managers. For example, associations between substrate type and benthic community composition have been used to generate precise maps of scallop habitat and to establish links between scallop abundance and substrate. For Browns Bank, four maps - shaded relief, backscatter intensity, surficial sediments and benthic habitat - have been exported to electronic charts and are now used in real time to guide offshore fishing effort. The environmental and economic benefits have been immediate, with reduced effort to achieve quotas, less bottom disturbance, and containment of fishing activity to known scallop grounds. Stock assessments and management practices have also been improved.

Other pilot projects in Atlantic Canada and the northeastern USA have demonstrated the value of integrated sea floor mapping in designating and managing marine protected areas (The Gully, Stellwagen Bank), in identifying offshore hazards such as landslides, in siting offshore structures, cables and pipelines, and in addressing environmental issues such as the routing of outfalls and disposal of dredge materials and mine tail