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  • This report on underwater noise is a contribution to the Strategic Environmental Assessment (SEA7) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). This report initially gives a general introduction to underwater ambient noise and the underlying mechanisms that generate sound. The report then identifies a number of sources of underwater acoustic noise, describes the characteristics of the noise including frequency content, levels and variability, and also identifies the current state of knowledge on each source. In all cases the sources are considered in the context of the SEA 7 area. Mechanisms that can modify the ambient sound levels are described. The dominant noise sources in the SEA 7 area are identified. Recommendations are then made for the methodology to be used to obtain meaningful characterisation of noise levels in order to establish baseline levels. The report then goes on to present an analysis of measured ambient noise data in the SEA 7 area, model predictions of spectrum levels, and compares the measured and modelled data.

  • This report is a contribution to the Strategic Environmental Assessment (SEA6) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). This report reviews the many different sources of underwater noise, both natural and anthropogenic, that combine to provide the background noise levels in which marine organisms need to survive throughout the SEA6 region. The sources of sound combine together in a complex manner resulting in significant spatial and temporal variations in the noise field. A map of the dominant noise sources in the Irish Sea is shown, indicating that man-made noise is the dominant source of noise over about 70% of the area. Shipping noise is likely to be dominant across large parts of the SEA6 area. To fully characterise the ambient noise field in the SEA6 area would require multiple measurements at a large number of locations over a period of a year. However, a considerably lower cost approach would be to characterise each sound source and to use this with occurrence statistics for each source to model the ambient noise field across the region. The advantages and disadvantages of the acoustic modelling approach are discussed.

  • As part of Strategic Environmental Assessment SEA1, sediment samples were collected at the request of the Department of Trade and Industry (now Department of Energy and Climate Change) a survey programme was conducted from the NERC Royal Research Ship (RRS) Charles Darwin between July and September 2000, with samples for a number of chemical and biological analyses being collected. An Excel file containing details of heavy metal analysis is available.

  • This report is a contribution to the Strategic Environmental Assessment (SEA5) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). A review of the distribution and abundance of divers, grebes and seaduck in the SEA 5 area was carried out by Cork Ecology at the request of the Department of Trade and Industry as part of the production of the SEA 5 Consultation Document. The study area was defined as the east coast of Scotland from the English border north to John O'Groats, including Orkney and Shetland, and the offshore waters in the SEA 5 area. This review considered thirteen species: red-throated diver, black-throated diver, great northern diver, great crested grebe, red-necked grebe, slavonian grebe, scaup, eider, long-tailed duck, common scoter, velvet scoter, goldeneye and red-breasted merganser.

  • This report is a contribution to the Strategic Environmental Assessment (SEA7) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change).The class Cephalopoda comprises three major divisions, of which two: Decapoda (squids and cuttlefish) and Octopoda (octopods) are represented in the SEA 7 Area. They are highly developed, but short-lived molluscs with rapid growth rates. They are important elements in marine food webs and interact significantly with marine mammals, seabirds and commercially exploited finfish species. They also represent a promising future fishery resource in terms of market value, abundance and growth potential. At present, only an estimated 10% of exploitable stocks are utilised worldwide. There are six marketable squid species that occur in the SEA 7 Area. These belong to the long-fin (loliginid) and short-fin (Ommastrephid) squids the two most important exploited families of decpods. In the SEA 7 Area, only one species, Loligo forbesi is commercially exploited on a regular basis, although there are significant landings of other species on occasion. The closely related Loligo vulgaris sometimes appears in catches and the small Alloteuthis subulata is thought to be naturally abundant and an important food item in the marine ecosystem. There are other important species represented in the SEA 7 Area. These include cuttlefish, octopods, sepiolids and a number of deep-water species. Most of these are marketable and may be ecologically important. Large fisheries for some of these species, particularly octopods and cuttlefish operate in European waters further south, but they are not currently exploited in the SEA 7 Area.

  • This report is a contribution to the Strategic Environmental Assessment (SEA7) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). The report concentrates on reviewing existing data and published sources, rather than attempt a quantitative baseline of wrecks and casualties. There is a comprehensive corpus of legislation, plans and polices concerned with the protection of the submerged maritime archaeological resource within the SEA 7 study area. The study outlines the known history of maritime activity within the SEA 7 area. Despite being an extremely large body of water that at times can produce dangerous sea and weather conditions, and encompasses the rugged coastlines of western Scotland and Northern Ireland, the area has been used extensively by seafarers from at least the Mesolithic (from 9000 BC) up to present times. During each time period there has been evidence of human activity within the SEA 7 area, often demonstrated by the discovery of maritime archaeological remains. The waters between the north east of Ireland and Scotland have been used as a means of communication throughout the centuries. Previous investigations of maritime archaeological remains within the SEA 7 area are discussed in the report. The spatial distribution of submerged archaeological remains is discussed, and comments are made on the limitations of any mapped baseline of data. The study concludes with a comment on the potential impacts of oil and gas activities on the submerged maritime archaeological resource and suggests possible monitoring methodologies.

  • This report is a contribution to the Strategic Environmental Assessment (SEA4) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change) and discusses temporal variability in benthic populations from the Faroe-Shetland Channel. The West of Shetland transect is situated between 60 40 N, 2 15 W; 61 20 N - 2 50 W, to the North and West of the Shetland islands. Statistical analyses was carried out on data collected previously.

  • This report is a contribution to the Strategic Environmental Assessment (SEA2) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). SEA2 focuses on the mature areas of the North Sea UK continental shelf which is divided into 3 areas - Northern, Central and Southern North Sea. This paper provides an overview of cephalopods - squid, octopus, cuttlefish in the SEA2 area. Cephalopods are short-lived, carnivorous animals that have rapid growth rates and play an important part in oceanic and coastal food webs. They are preyed on by cetaceans, fish and seabirds, and are predators themselves, feeding on fish, crustaceans, molluscs and cephalopods. Knowledge of cephalopod distribution in Scottish waters is mainly based on information from commercial whitefish vessels that catch squid as a by-catch. The loliginid squid Loligo forbesi is the predominant species. English cephalopod landings are dominated by cuttlefish caught in the English Channel outside the area of interest. The benthic octopod Eledone cirrhosa, though a highly valued species in southern Europe, is usually discarded by fishermen in Scottish waters. Fishery management statistics indicate that the areas of highest abundance of Loligo forbesi and of Eledone cirrhosa lie outside the SEA2 area. Cephalopods naturally accumulate high levels of trace metals. The potential of drilling operations to introduce trace metals into the sea is discussed. It is concluded that the overall impact on cephalopods and cephalopod fisheries in the SEA2 area by further oilfield development would be slight.

  • This report is a contribution to the Strategic Environmental Assessment (SEA3) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change) and is an addendum to "SEA2 Technical report 009 - Cephalopods, covering overview of cephalopod population, ecology, fisheries, sensitivity" by same authors. This paper provides an overview of cephalopods - squid, octopus, cuttlefish - in the SEA2 and SEA3 areas of the North Sea. Cephalopods are short-lived, carnivorous animals that have rapid growth rates and play an important part in oceanic and coastal food webs. They are preyed on by cetaceans, fish and seabirds, and are predators themselves, feeding on fish, crustaceans, molluscs and cephalopods. Knowledge of cephalopod distribution in Scottish waters is mainly based on information from commercial whitefish vessels that catch squid as a by-catch. The loliginid squid Loligo forbesi is the predominant species. English cephalopod landings are dominated by cuttlefish caught in the English Channel outside the area of interest. The benthic octopod Eledone cirrhosa, though a highly valued species in southern Europe, is usually discarded by fishermen in the SEA2 and SEA3 areas. Fishery management statistics indicate that the areas of highest abundance of Loligo forbesi and of Eledone cirrhosa lie outside the SEA2 and SEA3 areas. Cephalopods naturally accumulate high levels of trace metals. The potential of drilling operations to introduce trace metals into the sea is discussed. It is concluded that the overall impact on cephalopods and cephalopod fisheries in the SEA2 and SEA3 areas by further oilfield development would be slight.

  • This report is a contribution to the Strategic Environmental Assessment (SEA3) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change) and has been written as an addendum to the more comprehensive SEA2 document. The two papers give an overview of the phytoplankton and zooplankton community composition in the North Sea and how this has fluctuated through the latter half of the 20th Century in response to environmental change. The study is based on a unique long-term dataset of plankton abundance in the North Atlantic and the North Sea acquired by the Continuous Plankton Recorder (CPR). The dinoflagellate genus Ceratium dominates the phytoplankton community in the North Sea, but diatoms are also important, especially in the southern part. The normal annual blooms of plankton are discussed, as are harmful algal blooms (HABs), which appear to be on the increase, possibly due to a combination of climatic variability and eutrophication. Among the zooplankton, copepods are particularly important and constitute a major food resource for many commercial fish species, such as cod and herring. Calanus is the dominant copepod genus in the North Atlantic. Other important components of the plankton - meroplankton, picoplankton and megaplankton - are also reviewed. Very small picoplankton (~1 micron in diameter) and much larger gelatinous members of the megaplankton (e.g. jellyfish and ctenophores) are poorly sampled by the CPR. Although the picoplankton represents a sizeable fraction of total primary production, its role in the marine ecosystem is poorly understood.