Assessment of the U.S. Outer Continental Shelf Environmental Studies Program II. Ecology (1992) / Chapter Skim
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3. Analysis of the Program
3. Analysis of the Program
Pages 41-98
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From page 41... ...
Integrative models of the consequences of oil spills, including estunates of contact with bird populations and consequent mortality, physiological, and population changes.
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From page 42... ...
A large amount of effort was expended in the Beaufort Sea region, which has a small number of pelagic birds breeding there, but in fact the effort was spent mainly on investigation of shoreline and lagoon habitats, where migratory birds and waterfowl are concentrated and are potentially vulnerable to OCS activities. The avocation in California of 29% of ad the program funds allocated to birds appears out of proportion to the small numbers of marine birds that breed In California, but it is not; much of the work was conducted on the numerous migratory and wintering species and on erects studies that could be generalized to other regions.
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From page 43... ...
In the broad overview, the program supported a wide variety of research endeavors that added greatly to our knowledge of marine birds In a very short period. Most of the knowledge is available In the Gray literature, and a fairly large amount is becoming available in the refereed literature.
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From page 44... ...
The sites for pelagic inventories of marine birds and pelagic process studies were decided more by the dictates of other programs in charge of ship use than by needs for adequate coverage to discern where and why marine birds might congregate at sea. Relatively little work was devoted to studying the distribution of vulnerable species (e.g., alcids)
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From page 45... ...
To the extent that such areas are near colonies or are along Denigration routes, it can be expected that large numbers of birds win be concentrated in small areas. MMS should focus on process studies within foraging range of colonies and in known major migration routes to determine where predictably large concentrations of birds wiD occur.
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From page 46... ...
No MMS studies of pelagic distributions of birds of E the Oregon and Washington coasts have been published, although a stucly of this region is to be completed In 1991. In the Gulf of Me~nco, surveys of the distribution of marine birds have provided poor coverage of the area and only fair coverage of seasonal patterns of abundance.
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From page 47... ...
Process studies are therefore essential, if effects of local or short-term environmental changes are to be detected. Colony process studies can provide information on the natural range of variation in system characteristics, an early warning of potential problems, and a means of detecting and predicting changes caused by environmental factors other than OCS activities.
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From page 48... ...
Properly planned and executed, colony process studies could have been invaluable in identif~r~ng short-tenn changes and In correlating them with environmental changes. Without continuing studies, it wiD be difficult or unpossible to identif y natural causes of observed changes and hence to rule out OCS activities as causes of these changes.
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From page 49... ...
The process studies in the intertidal zone have yielded data essential for assessing the vulnerability of areas used as staging areas by important populations of shorebirds and waterfowl. 49 Effects Studies, Modeling, and Estimation of Risk The MMS program has put only a small percentage of its seabird program effort into investigations of the potential effects of OCS activities on birds.
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From page 50... ...
Shoreline Habitat Inventories The inventories of the shoreline habitat and nearshore waters throughout most OCS regions are generally insufficient to let MMS assess the potential risk of impact or the actual loss of birds if an oil spill occurs; data gaps appear particularly severe for the coasts of the Gulf of Mexico, the midge and south Atlantic seaboard, Cape Cod, and the Gulf of Maine. Data are also apparently unavailable for the northern California, Oregon, and Washington coasts.
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From page 51... ...
Shoreline and Nearshore Process Studies For many, if not most, of the known major staging areas, the energetic consequences and the resulting impact on bird populations of the partial or complete loss of what are thought to be critical habitats for both waterfowl and shorebirds are unknown. Effects There are insufficient data on the behavior of birds at oil slicks.
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From page 52... ...
Surveys of areas of such potential impact need to include not only avian use of salt marsh, lagoon, and Intertidal flats and beach, but also nearshore waters to 5 km offshore. Colony Process Studies The panel recognizes that data on age-specific fecundity, recruitment, and mortality are unporcan~, cut ~ Is nor practical to begin a project intended to measure them at this late stage In the ASP program.
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From page 53... ...
The pane} sees the resulting data as more important for monitoring the status of populations than mere counting of birds at colonies. 53 At-Sea Process Studies MMS should conduct studies of the processes that affect the at-sea distribution of foraging birds near major colonies that are potentially exposed to oft spins from OCS activities.
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From page 54... ...
On the basis of data acquired An process studies, life tables should be developed to relate adverse changes In survival or productivity to long-term population size and recovery rates; at the least, this wiD require extension and generation of the mode]
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From page 55... ...
waters as 55 i, ., endangered and their apparent vulnerability to OCS activities, although it has recently supported a study of the associations of turtles with oil platforms (Lohoefener et al., 1990~. As pointed out In a recent NRC report (NRC, 199Ob)
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From page 56... ...
Environmental Studies Program and Results Inventory Inventories of the species of marine mammals present and the seasonal patterns of their distribution and abundance are of fundamental importance In evaluating potential impacts. Because many marine mammals are migratory and inhabit remote locations, MMS has funded major aerial survey programs over the last decade.
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From page 57... ...
Studies in the Alaska region have been conducted in the Gulf of Alaska, the Aleutian Islands, and the Benng, Chukchi' and Beaufort seas. The MMS-funded surveys have been complemented by a report on the status of 10 marine mammals in Alaskan waters (Lentfer, 1988)
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From page 58... ...
concentrated primarily on pinnipeds and sea otters along the central and northern California coast. Their transects were perpendicular to the coast to a distance of about 250 km.
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From page 59... ...
Surveys of the distribution and abundance of seals and sea otters in lease-sale areas have been funded by MMS in most regions of the Pacific coast, including Alaska, although some of these surveys are over 10 years old. Combined with data gathered by other agencies, and within reasonable limits, these surveys provide adequate stock assessments for some species (harbor seals, sea lions, fur seals, and sea otters)
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From page 60... ...
Even though the oil that Is transported through Prince William Sound does not come Tom an OCS source, and MMS was not the primary agency responding to the E=07' Va~z spilt MMS responded quickly to provide some funding for studies that could take advantage of the opportunity it presented. Research efforts on sea otters were, however, managed by FWS, the agency responsible for sea otter management.
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From page 61... ...
MMS has sponsored research on the effects of of} on sea otters. It Included behavior of captive animals exposed to slicks (Siniff et al., 1982)
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From page 62... ...
Because offshore petroleum operations involve activities that produce underwater sound, there is a potential for them to interfere with sound produced by cetaceans as wed as to cause disturbance and stress. Even as recently as 1980, there was very little information about the frequency composition and intensity of underwater sound produced by such petroleum-related activities as drilling, dredging, and vessel traffic or the intense sound produced during seismic exploration.
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From page 63... ...
Bowhead whales were the primary species of concern in the Alaskan Beaufort Sea, an area that was considered particularly likely to yield oil and gas, owing to its proximity to the supergiant Prudhoe Bay oilfield. As an early step to understanding the problem that might be presented by underwater sound, the U.S.
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From page 64... ...
Modeling of Interactions Between Oil Spills ant! Marine Mammals The environmental studies program has recently funded modeling efforts that have attempted to explore the effects of oil spills and other petroleum-related activities on various mar~ne-mammal populations.
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From page 65... ...
Trophic S - ies Trophic studies have been done in both the Alaskan and Canadian Beaufort seas to detenrune if changes in abundance of bowhead whales are correlated with changes In oceanographic conditions, and productivity. Griff~ths and Buchanan (1982)
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From page 66... ...
However, data on cetaceans and pinnipeds of the Pnnce William Sound region are sparse, although some seasonal surveys have been made. Because this area seems to be at high risk, basic Inventory and process studies on all marine mammals would also be appropriate.
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From page 67... ...
contamination on the two most sensitive species: sea otters and fur seals. These studies have generally shown that rehabilitation of the two species after oiling is possible, but have pointed to the need for extensive facilities where rehabilitation programs can be executed.
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From page 68... ...
waters by marine mammals has provided an understanding that is generally adequate for assessment of the potential for damage from OCS activities, but not as the basis for assessing change (including the measurement of impacts of actual events)
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From page 69... ...
That effort is extremely expensive. In the case of sea otters In Prince William Sound, probably only a small fraction of the animals contaminated with oil were captured and treated (Trustee Council for the In V~z Natural Resource Damage Assessment, 1991)
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From page 70... ...
For example, long-term data on harbor seals and northern sea lions in the Prince William Sound area before the E=on Chavez spin are minimal. Some survey data are available from MMS contracts with the Alaska Department of Fish and Game and other sources, but they are sparse.
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From page 71... ...
assessed the benthic programs supported by the ESP and evaluated their contributions to advances in marine benthic ecology and predictions of the impacts of OC:S operational activities. The effects of some OCS activities, such as the discharge of driDing fluids and accidental oil spins, and the long-term effects of offshore oil and gas development have been reviewed extensively by previous groups (NRC, 1983, 1985; Boesch and Rabalais, 1987~.
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From page 72... ...
bordered by deeper channels; Gulf of Maine ninth irregular bedrock and basins; large sand shoals and waves of Nantuclcet Shoal$ shelf edge incised by submarine canyons Au loch th on ous Middle Atlantic Bitt Broad, gently sloping platform Autochthonous with complex Mondale topography of ridges and smaller sand waves, sedimentf~ed channels South Atlantic Bight West Florida Shelf Broad, gently sloping platform with cross shelf shoab, sand waves, rocky outcrops; calcareous reefs at shelf break; no submarine canyons Broad, gently sloping platform Autochthonous of carbonate sand sheet with subsurface or loser relief exposed hard strata at mid and outer shelf and algal nodule areas at shelf break North Central Gulf of Broad, gentry eloping shelf Autochthonous/ Mexico except at Mississippi River Allochthonous prodelta and De Soto Canyon; edges and pinnacles on outer shelf and at shelf break Autochthonous Northwestern Gulf of Mexico South Texas Low depositional, dominantly sands with Major area SW of Georges Bank, Mud gravels in areas, sand shoals Patch,. heads of and waves in shallower areas, grade to medium to fine sands mid shelf Low depositional, dominantly sends >75%, mostly >9Wo, fine-grained sediments generally absent except for some accumulation in depressions Low depc~sitional, coarse to medium sands with finer sands at depth, little fine fraction except in capeassociated ~shadows.
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From page 73... ...
nondepositional; thick, southeastern shelf NE, prograding Yukon delta in muddy deposits in Norton Norton Sound Sound Alaskan Arctic Broad, gentry eloping marginal Climax Grading Majontyof Chukchi Shelf Low sediment transport shelf in Chukchi Sea to very with 54 sediments; Beaufort nearshore and narrow shelf in Beaufort Sea; shelf with primarily sandy predominantly little bathymetric relief except muds and silt and clay at westward, possible for Barrow Sea Valley and shelf edge, gravels at shelf depositional site in SW Hanna Shoal in Chukchi Sea break, some input from Harrison Bay for river run-off, tundra Cohrille River delta slumping, and river ice muds Gulf of Alaska Broad, gentry eloping marginal Autochthonous/ Mostly reworked glacial off Troughs off Kodiak shelf, dynamic bedforms of Cldmax Grading Kodiak, shelly sands (except Stevenson) , sand waves (8 to 15 m high; nearshore, coarse sediments volcanic ash as indicator major submarine valleys and on banks, fine in troughs; of present day dispersal basins in NE, series of flat silts/clays and 0th pattems; removed from banks (50 to 100m)
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From page 74... ...
Generally low wave regime, most 0~1.0 m (summer-winter3 Low wave regime 05 m in summer to 1.0 m in winter, historical maximum of 73 m In summer Seasonal wind-generated currents and waves, hurricanes, winter frontal passages Seasonal wind-generated currents and waves, particularly in winter, high frequency of hurricanes, winter frontal purges River discharge, inshore effects as far west as Galveston, wind-generated currents and waves, high frequency of hurricanes, winter frontal passages, widespread seasonal hypoxia Mixed diurnal and semidiurnal, Low wave regime, Persistent SE winds low magnitude 0.4 05 m; tidal most 0.9-1.8 m; predominate, along with current velocity <14 cm/s summer, most ~ winter northerly winds cause 0.6 m; winter, wind-generated currents and most 1.2-1.8 m; waves, high frequency of waves up to ~3 m hurricanes, winter frontal in hurricanes Southern Mixed semidiurnal, of moderate Average California magnitude, 0~25 m significant wave heights 1-2 m, tsunamis with waves of 63 m I Realized turbidity fronts, seasonal sand ripples, nearbottom nepheloid layers influenced by storms, frontal Wages, bottom currents; strong nepheloid layer at mid shelf Spring turbid bottom waters (surface also) near Mississippi River, water column turbid whole depth in winter Nepheloid layers and turbidity currents, nearbottom nepheloid layer present an seasons except winter, in <20 m associated with wind-generated currents Near-bottom turbidity all seasons, variable in thickness and distribution, related to thermal mixing, internal waves, Seashore suspension by waves and tidal Wang passages Wind-generated nearshore Sediment erosion from water movements, prevailing exposed shallow shelf with winds from NW (1~32 deposition in basins of km/hr3, more onshore in southern California summer, swing, and summer borderland upwelling, occasional small tsunamis, periodic El Ni n 0 events, seismicity
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From page 75... ...
which flows into Shelil~of Strait Bering Sea Mixed semidiurnal tides with Larger waves in Severe storms may double In NE, major storm marked diurnal inequalities; in SE up to 10-20 m, strength of wind-generated surges every several years southern area near peninsula lower in NE up to currents and waves, NO resuspend and transport and land restrictions up to 5 m, 7 m, maximum differences in storms; ice sediments; dynamic in NE tides <05 m wave heights 32 movements, dense coverage, sediment transport by ice m, waves most ice presence, N-S differences; gouging, storm waves, influential in tsunamis in North Aleutian and ice loading shallow Norton shelf; potential seismicity and Sound and Bristol volcanism Bay Alaskan Arctic Mixed semidiurnal tides with mean range of 10 to 30 cm, small tidal currents of 03 05 cm/s Extreme storm Severe storms with 0th Storm-affected sediments waves not as winds but waves tempered by in Chakchi Sea, ice likely as in Bering sea ice, gouging by offshore gouging on seabed out to Sea or Gulf of pack ice, offshore subsea 60 m in whole area; low Alaska because permafrost, active ice flow coastal sediment generation lead along Chukchi Sea hampered by pack coast, coastal erosion on ice, 25 m waves Beaufort Sea coast during storms, only 22% >05 m transport inshore on Beaufort Shelf, some reworking of coarse sediments by hydrodynamic forces on inner and central shelf Source: Adapted from Rabalais and Boesch, 1987.
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From page 76... ...
Syst. Flor., 1977; Dames Warm, temperate Carolinian Central 21-25 ° 22° & Moore, 1979; Lyons & Collard, affinities, separated by some Gulf of 1974 from northern Gulf Wof Mexico Mississippi River, outer shelf tropical affinities North- 1516° to 27-28 ° 18-19° to 19-20° to Ward et al., 1979; Bedinger, 1981; Warm, temperate Carolinian western 21-25° 22° Middleditch, 1981; Jackson, 1977; affinities, separated by some Gulf of Hann & Randall, 1980; DeRouen et from northern Gulf E of Mexico al., 1982 Mississippi River, outer shelf tropical affinities South Texas 1~15° to W17° to 19-22° with Holland 19T7, 1979; Flint, 1981; Mostly warm, temperate 28° with 25° with latitudinal Flint ~ Holland, 1980; Flint & Carolinian affinities with more latitudinal latitudinal differences Rabalais, 1980a,b, 1981 subtropical influence, considered differences differences by some as Texas transitional between temperate and tropical outer shelf tropical affinities Southern 1~14° to 17- 1~13° to 1~13° to Jones, 1969; BaInard & Hartman, Transitional between southern California 195° with 15-17° 15 17° 1959; Barnard, 1963; Fauchald & subtropical Panamanian penance latitudinal @ 200m Jones, 1977,1978; Balcom, 1981 and northern temperate differences ~9° Oregonian province throughout year
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From page 77... ...
continental shelf habitats, the ESP has contributed to our understanding of marine biogeography, an~malsed~ment relationships, and the unportance of shelf ecosystems In food~hain dynamics. In recent programs, the fate of chemicals in continental shelf habitats (Bothner et al., 1983; Boehm and Farrington, 1984; Boehm, 1987; Boehm et al., 1987; Boehm et al., 1990)
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From page 78... ...
Northwestern Gulf of L~nbrineris, Paraprionospio, Cossura, Ninoe, Nephtys, No shelf break stations Me~aco Magelona, Sigambra,Diopatra Notomastus, Lumbrineris, O,Golfingia(s) ,Ampel~sca (a)
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From page 79... ...
Although the relative sensitivities of coastal habitats to oil spiDs have been evaluated (Gun~ach and Hayes, 1978; Owens and Robilliard, 1981) , little effort has been spent on comparing the sensitivities of shelf habitats or assessing OCS impacts other than oil spills.
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From page 80... ...
Penaeid and sicyonid shrimp, portunid crabs, sciaenid fishes, Seasonal changes in abundance and dominance, variability in community structure related to sediment differences both with depth and physiography and to seasonal hypoxia on inner shelf Some seasonal differences but not consistent over depth or latitude gradients, large-scale community differences related more to sediment distributions and hydrographic variability Seasonal recruitment shown by aggregations of Amphiodia in summer on mainland shelf, no apparent seasonality in basins; large-scale differences related to complex topography Numerous hard substrates with epibenthic fauna and hermatypic corals, algal nodule substrates, nearshore seamless beds, Florida Middle Grounds Exposed hard substrate areas on outer shelf and at shelf break Penaeid shrimp, portunid crabs, Ted salt dome banks of saaenid fishes, flatfishes carbonate sediments on outer shelf and shelf break, many with hermatypic corals, most with top environmental priority ranking, East and West Flower Gardens Penaeid shrimp, portunid crabs, Eyed salt dome banks of sciaenid fishes, flatfishes carbonate sediments on outer shelf, most with low diversity epibenthic communities, most with low environmental priority ranking Sea basses, sciaenid fishes, sea urchins and starfish, cancroid crabs, pandalid shrimp Scattered submerged ridges and topographic highs in complex borderland, rocky banks at shelf edges, some in shallower water with purple coral (Allopora) , others with rich epibiota; kelp forests, Tanner and Cortez Banks
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From page 81... ...
concluded that four features of continental shelf habitats could be used for a comparative evaluation of habitat sensitivities: . Sedunenta~y regime, with depositional areas being the ultimate repository of particle-bounc]
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From page 82... ...
Matthew Hall Navarin Basin Norton Basin Hope Basin Chukchi Sea Beaufort Sea Source: Adapted from Rabalais and Boesch, 1987.
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From page 83... ...
Greater attention should also be placed on characterizing the impacts of all operational discharges from OCS activities. Ibe ejects of driDing-fluid discharges have been reviewed extensively (NRC, 1983~; water-based drilling fluids used In U.S.
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From page 84... ...
Data on several recent oil spills suggest that the medium- and higher-molecular-weight aromatic hydrocarbons, such as aLkylated phenanthrenes and alkylated dibenzothiophenes, are among the most persistent petroleum hydrocarbons in both animal tissues and sediments (Grahl-Nielsen et al., 1978; Roesijadi et al., 1978; Teal et al., 1978;
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From page 85... ...
Once confined In aquatic sediments, the more complex fractions remain for Indeterminate periods. Where long-term persistence of petroleum hydrocarbons has been documented, sublethal effects have been observed.
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From page 86... ...
The pretreatment differences are then compared statistically against a tune-ser~es of differences after application of the impact. A branch of applied statistics that needs further development to enhance environmental monitoring studies is power analysis.
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From page 87... ...
, it is difficult to ascertain the relationship between these responses and large-scale alterations In the functioning of marine ecosystems and the harvesting of fishery resources. Because the spatial scales of lanai dispersal of continental shelf benthos are so large and the natural mortality of larval marine benthic Invertebrates is extremely high, population sizes might be largely decoupled from the reproductive output of spawning adults.
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From page 88... ...
The ESP has the responsibility to assess not only the impacts of offshore exploration and development, but also the ejects of transportation or other support activities on shoreline habitats. An environmental monitoring program that wid improve understanding of the impacts on benthic processes of OCS activities on the U.S.
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From page 89... ...
E1SHE:RIES MMS has sponsored many studies on fishery resources and some studies on the structure and function of ecosystems. However, the studies have pronded relatively few quantitative assessments of the effects of OCS oil and gas activities on fishery resources, and assessments of the effects on ecosystems are almost completely lacking.
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From page 90... ...
that govern the production and abundance of populations. Research might be necessary on the degree to which mobile organisms avoid and are likely to come into contact with oil and other material originating from OCS active For fishery resources, traditional models of fishery population dynamics can be e~an`ded to account for other sources of stress, such as those resulting from OCS activity (e.g., Schaaf et al., 1987~.
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From page 91... ...
Fish Invertebrates/plankton FIGURE 3-1 Companson of lethal and sublethal effects of petroleum hydrocarbons on fish and invertebrates. Source: Vandermeullen and Cape, 1983.
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From page 92... ...
Techniques developed In them are suitable for application in monitoring the effects of OCS activities, especially the short-term effects of produced waters and the long-term effects of accidental petroleum discharges. Similar studies were conducted during the evaluation of the effects of the Eaton Valdez oil spilL but the results were not available to the panel for review.
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From page 93... ...
Although the stub was valuable In helping to predict recovery tunes for a population of sea otters after oil spills of different magnitudes and in different regions of the California coast, and it also demonstrated the need for additional ~nfonnation data on various population measures.
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From page 94... ...
Nevertheless, contaminated particles might be transported to other locations and incorporated into the food webs there. Fishery Models MMS has sponsored the development of two fishery models to assess the effects of OCS activity quantitatively: the Georges Bank model (developed by Spaulding, et al., 1982)
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From page 95... ...
The Bering Sea model shares the two shortcomings of the Georges Bank model. It assumes passive drift of eggs and larvae according to vertically averaged horizontal currents; empirical data on the spatial and temporal distribution of eggs and larvae in this region are inadequate for use In impact assessment or mode!
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From page 96... ...
It Is not sufficient for deter~runing the longer-term distribution of discharged material; it was not designed to provide more than short-term near-i ield distributions. Evaluation of MMS Modeling Efforts Aside from a major expenditure of resources to develop a f ishery model, MMS has made few attempts to use models to consider oil and hydrocarbon effects on marine organisms.
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From page 97... ...
The type of data needed to verify their output is lacking. This field needs improvement, especially if MMS desires to focus on long-term effects of OCS activities.
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