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Exxon Neftegas Limited, operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG), on behalf of the Sakhalin-1 consortium, conducted a 3-D seismic survey of the Odoptu license area during 17 August-September 2001. A portion of the primary known feeding area of the endangered western gray whale ( Eschrichtius robustus ) is located adjacent to the seismic block. The data presented here were collected as part of daily monitoring to determine if there was any measurable effect of the seismic survey on the distribution and abundance of western gray whales. Mitigation and monitoring program included aerial surveys conducted between 19 July and 19 November using the methodology outlined by the Southern California High Energy Seismic Survey team (HESS). These surveys provided documentation of the distribution, abundance and bottom feeding activity of western gray whales in relation to seismic survey sounds. From an operations perspective, the aerial surveys provided near real-time data on the location of whales in and outside the feeding area, and documented whether whales were displaced out of an area normally used as feeding habitat. The objectives of this study were to assess (a) temporal changes in the distribution and abundance of gray whales in relation to seismic survey, and (b) the influence of seismic survey, environmental factors, and other variables on the distribution and abundance of gray whales within their preferred feeding area adjacent to Piltun Bay. Multiple regression analysis revealed a limited redistribution of gray whales southward within the Piltun feeding area when the seismic survey was fully operational. A total of five environmental and other variables unrelated to seismic survey (date and proxies of depth, sea state and visibility) and one seismic survey-related variable ( seg3d , i.e., received sound energy accumulated over 3 days) had statistically significant effects on the distribution and abundance of gray whales. The distribution of two to four gray whales observed on the surface (i.e., about five to ten whales in total) has likely been affected by the seismic survey. However, the total number of gray whales observed within the Piltun feeding area remained stable during the seismic survey.

The introduction of anthropogenic sounds into the marine environment can impact some marine mammals. Impacts can be greatly reduced if appropriate mitigation measures and monitoring are implemented. This paper concerns such measures undertaken by Exxon Neftegas Limited, as operator of the Sakhalin-1 Consortium, during the Odoptu 3-D seismic survey conducted during 17 August’ September 2001. The key environmental issue was protection of the critically endangered western gray whale ( Eschrichtius robustus ), which feeds in summer and fall primarily in the Piltun feeding area off northeast Sakhalin Island. Existing mitigation and monitoring practices for seismic surveys in other jurisdictions were evaluated to identify best practices for reducing impacts on feeding activity by western gray whales. Two buffer zones were established to protect whales from physical injury or undue disturbance during feeding. A 1 km buffer protected all whales from exposure to levels of sound energy potentially capable of producing physical injury. A 4’ km buffer was established to avoid displacing western gray whales from feeding areas. Trained Marine Mammal Observers (MMOs) on the seismic ship Nordic Explorer had the authority to shut down the air guns if whales were sighted within these buffers. Additional mitigation measures were also incorporated: Temporal mitigation was provided by rescheduling the program from June–August to August–September to avoid interference with spring arrival of migrating gray whales. The survey area was reduced by 19% to avoid certain waters <20 m deep where feeding whales concentrated and where seismic acquisition was a lower priority. The number of air guns and total volume of the air guns were reduced by about half (from 28 to 14 air guns and from 3,390 in 3 to 1,640 in 3 ) relative to initial plans. ‘Ramp-up’(=‘soft-start’ procedures were implemented. Monitoring activities were conducted as needed to implement some mitigation measures, and to assess residual impacts. Aerial and vessel-based surveys determined the distribution of whales before, during and after the seismic survey. Daily aerial reconnaissance helped verify whale-free areas and select the sequence of seismic lines to be surveyed. A scout vessel with MMOs aboard was positioned 4 km shoreward of the active seismic vessel to provide better visual coverage of the 4’ km buffer and to help define the inshore edge of the 4’ km buffer. A second scout vessel remained near the seismic vessel. Shore-based observers determined whale numbers, distribution, and behavior during and after the seismic survey. Acoustic monitoring documented received sound levels near and in the main whale feeding area. Statistical analyses of aerial survey data indicated that about 5’0 gray whales moved away from waters near (inshore of) the seismic survey during seismic operations. They shifted into the core gray whale feeding area farther so...

Okhotsk or western gray whales feed in summer along the northeastern coast of Sakhalin Island, Russia, a region with oil and gas extraction facilities. Seismic surveys increased sound levels in the nearshore feeding area in 2015 for part of the summer, potentially displacing whales from preferred foraging habitat or reducing foraging efficiency. Since lost foraging opportunities might lead to vital rate effects on this endangered species, detailed benthic surveys were conducted to characterize benthic community biomass patterns and spatial and temporal differences. Benthic biomass demonstrated strong spatial–temporal interactions indicating that prey biomass differences among locations were dependent on sampling period. Of greatest interest, Amphipoda biomass declined from June to October in the northern and southern portions of the nearshore study area but increased in the middle and Actinopterygii biomass increased in the northern area in mid-summer. Water depth and sediment type were significant covariates with community structure, and water depth strongly covaried with bivalve biomass. Total average prey biomass was ~ 100 g/m2 within the nearshore feeding area with no evidence of reduced biomass among sampling periods or locations, although there were fewer amphipods in the south. Multi-prey investigations provide a stronger basis for inferences than single-prey studies of amphipods when gray whales feed on diverse prey. Benthic community-level variability was moderate to high as would be expected for a shallow-water nearshore area. Overall, spatial and temporal changes in dominant macrofauna biomass reflected small to medium-sized effects that were well within the natural boundaries expected for benthic communities.

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. The American School of Classical Studies at Athens is collaborating with JSTOR to digitize, preserve and extend access to Hesperia: The Journal of the American School of Classical Studies at Athens. H[rUMAN HABITATION PATTERNS are constrained by natural resources andprocesses. Any regional archaeological project must therefore first determine the primary resources provided by the natural setting, including the availability of fresh water, arable land, mineral deposits, building stones, and natural harbors, and, second, investigate the geological processes that may have distorted the original archaeological record, including erosion, deposition, tectonic movement, and coastal progradation and regression. Only when the quality and quantity of these factors are known will archaeological field projects be able to establish site size, function, and duration and reconstruct and interpret the historic interrelation between human habitation and landscape evolution.When the Pylos Regional Archaeological Project (PRAP) was conceived to investigate the history of settlement and land use in western Messenia (Peloponnesos, Greece), 1 it was decided that physical sciences would comprise a major component of the study. This article represents the preliminary report of the principal natural scientists who participated in the fieldwork for PRAP between 1991 and 1995.2 By employing an interdisciplinary team consisting of a geoarchaeologist (Eberhard Zangger), a soil scientist (Michael Timpson), a botanist and palynologist (Sergei Yazvenko), a geophysicist (Falko Kuhnke), and a hydroengineer (Jost Knauss), it was possible to reconstruct the environmental history of the landscape centered on the Palace of Nestor.3 Among the main results of this study are a continuous vegetation history for the past 7,000 years, the discovery of the earliest artificial port in Europe, and the discovery of a magnetic anomaly indicating a massive artificial structure northwest of the Palace of Nestor. CHARACTERISTICS OF MESSENIAWestern Messenia lies hidden in a far corner of the Greek mainland and is difficult to reach from the eastern Peloponnesos by land because three mountain ridges obstruct 1 See Davis et al. 1993Davis et al. , 1994aDavis et al. , 1994bDavis et al. , 1995Davis et al. , and 1997 for a description of PRAP and for preliminary archaeological results. The full illustrated texts of preliminary reports for the 1993-1995 seasons are available on the WorldWideWeb at http://classics.lsa.umich.edu/PRAP.html, as is a complete gazetteer of all archaeological sites investigated by PRAP and a catalogue of representative artifacts from them. The physical scientific research was funded through PRAP by the Institute...