12 resultados para Channel Islands National Marine Sanctuary (Agency : U.S.)
em Plymouth Marine Science Electronic Archive (PlyMSEA)
Resumo:
During the 1970s and 1980s, the late Dr Norman Holme undertook extensive towed sledge surveys in the English Channel and some in the Irish Sea. Only a minority of the resulting images were analysed and reported before his death in 1989 but logbooks, video and film material has been archived in the National Marine Biological Library (NMBL) in Plymouth. A study was therefore commissioned by the Joint Nature Conservation Committee and as a part of the Mapping European Seabed Habitats (MESH) project to identify the value of the material archived and the procedure and cost to undertake further work (Phase 1 of the study reported here: Oakley & Hiscock, 2005). Some image analysis was undertaken as a part of Phase 1. Phase 2 (this report) was to further analyse selected images. Having determined in Phase 1 that only the 35 mm photographic transparencies provided sufficient clarity to identify species and biotopes, the tows selected for analysis were ones where 35mm images had been taken. The tows selected for analysis of images were mainly in the vicinity of Plymouth and especially along the area between Rame Head and the region of the Eddystone. The 35 mm films were viewed under a binocular microscope and the taxa that could be recognised recorded in note form. Twenty-five images were selected for inclusion in the report. Almost all of the images were of level sediment seabed. Where rocks were included, it was usually unplanned and the sled was hauled before being caught or damaged. The main biotopes or biotope complexes identified were: SS.SMU.CSaMu. Circalittoral sandy mud. Extensively present between the shore and the Eddystone Reef complex and at depths of about 48 to 52 m. At one site offshore of Plymouth Sound, the turret shell Turritella communis was abundant. In some areas, this biotope had dense anemones, Mesacmaea mitchelli and (more rarely) Cerianthus lloydii. Queen scallops, Aequipecten opercularis and king scallops, Pecten maximus, were sometimes present in small numbers. Hard substratum species such as hydroids, dead mens fingers Alcyonium digitatum and the cup coral Caryophyllia smithii occurred in a few places, probably attached to shells or stones beneath the surface. South of the spoil ground off Hilsea Point at 57m depth, the sediment was muddier but is still assigned to this biotope complex. It is notable that three small sea pens, most likely Virgularia mirabilis, were seen here. SS.SMx.CMx. Circalittoral mixed sediment. Further offshore but at about the same depth as SS.SMU.CSaMu occurred, coarse gravel with some silt was present. The sediment was characterised must conspicuously by small queen scallops, Aequipecten opercularis. Peculiarly, there were ‘bundles’ of the branching bryozoan Cellaria sp. – a species normally found attached to rock. It could not be seen whether these bundles of Cellaria had been brought-together by terebellid worms but it is notable that Cellaria is recorded in historical surveys. As with many other sediments, there were occasional brittle stars, Ophiocomina nigra and Ophiura ophiura. Where sediments were muddy, the burrowing anemone Mesacmaea mitchelli was common. Where pebbles or cobbles occurred, there were attached species such as Alcyonium digitatum, Caryophyllia smithii and the fleshy bryozoan Alcyonidium diaphanum. Undescribed biotope. Although most likely a part of SS.SMx.CMx, the biotope visually dominated by a terebellid worm believed to be Thelepus cincinnatua, is worth special attention as it may be an undescribed biotope. The biotope occurred about 22 nautical miles south of the latitude of the Eddystone and in depths in excess of 70 m. SS.SCS.CCS.Blan. Branchiostoma lanceolatum in circalittoral coarse sand with shell gravel at about 48m depth and less. This habitat was the ‘classic’ ‘Eddystone Shell Gravel’ which is sampled for Branchiostoma lanceolatum. However, no Branchiostoma lanceolatum could be seen. The gravel was almost entirely bare of epibiota. There were occasional rock outcrops or cobbles which had epibiota including encrusting calcareous algae, the sea fan Eunicella verrucosa, cup corals, Caryophyllia smithii, hydroids and a sea urchin Echinus esculentus. The variety of species visible on the surface is small and therefore identification to biotope not usually possible. Historical records from sampling surveys that used grabs and dredges at the end of the 19th century and early 20th century suggest similar species present then. Illustrations of some of the infaunal communities from work in the 1920’s is included in this report to provide a context to the epifaunal photographs.
Resumo:
During the 1970’s and 1980’s, the late Dr Norman Holme undertook extensive towed sledge surveys in the English Channel and some in the Irish Sea. Only a minority of the resulting images were analysed and reported before his death in 1989 but logbooks, video and film material has been archived in the National Marine Biological Library (NMBL) in Plymouth. A scoping study was therefore commissioned by the Joint Nature Conservation Committee and as a part of the Mapping European Seabed Habitats (MESH) project to identify the value of the material archived and the procedure and cost to undertake further work. The results of the scoping study are: 1. NMBL archives hold 106 videotapes (reel-to-reel Sony HD format) and 59 video cassettes (including 15 from the Irish Sea) in VHS format together with 90 rolls of 35 mm colour transparency film (various lengths up to about 240 frames per film). These are stored in the Archive Room, either in a storage cabinet or in original film canisters. 2. Reel-to-reel material is extensive and had already been selectively copied to VHS cassettes. The cost of transferring it to an accepted ‘long-life’ medium (Betamax) would be approximately £15,000. It was not possible to view the tapes as a suitable machine was not located. The value of the tapes is uncertain but they are likely to become beyond salvation within one to two years. 3. Video cassette material is in good condition and is expected to remain so for several more years at least. Images viewed were generally of poor quality and the speed of tow often makes pictures blurred. No immediate action is required. 4. Colour transparency films are in good condition and the images are very clear. They provide the best source of information for mapping seabed biotopes. They should be scanned to digital format but inexpensive fast copying is problematic as there are no between-frame breaks between images and machines need to centre the image based on between-frame breaks. The minimum cost to scan all of the images commercially is approximately £6,000 and could be as much as £40,000 on some quotations. There is a further cost in coding and databasing each image and, all-in-all it would seem most economic to purchase a ‘continuous film’ scanner and undertake the work in-house. 5. Positional information in ships logs has been matched to films and to video tapes. Decca Chain co-ordinates recorded in the logbooks have been converted to latitude and longitude (degrees, minutes and seconds) and a further routine developed to convert to degrees and decimal degrees required for GIS mapping. However, it is unclear whether corrections to Decca positions were applied at the time the position was noted. Tow tracks have been mapped onto an electronic copy of a Hydrographic Office chart. 6. The positions of start and end of each tow were entered to a spread sheet so that they can be displayed on GIS or on a Hydrographic Office Chart backdrop. The cost of the Hydrographic Office chart backdrop at a scale of 1:75,000 for the whole area was £458 incl. VAT. 7. Viewing all of the video cassettes to note habitats and biological communities, even by an experienced marine biologist, would take at least in the order of 200 hours and is not recommended. English Channel towed sledge seabed images. Phase 1: scoping study and example analysis. 6 8. Once colour transparencies are scanned and indexed, viewing to identify seabed habitats and biological communities would probably take about 100 hours for an experienced marine biologist and is recommended. 9. It is expected that identifying biotopes along approximately 1 km lengths of each tow would be feasible although uncertainties about Decca co-ordinate corrections and exact positions of images most likely gives a ±250 m position error. More work to locate each image accurately and solve the Decca correction question would improve accuracy of image location. 10. Using codings (produced by Holme to identify different seabed types), and some viewing of video and transparency material, 10 biotopes have been identified, although more would be added as a result of full analysis. 11. Using the data available from the Holme archive, it is possible to populate various fields within the Marine Recorder database. The overall ‘survey’ will be ‘English Channel towed video sled survey’. The ‘events’ become the 104 tows. Each tow could be described as four samples, i.e. the start and end of the tow and two areas in the middle to give examples along the length of the tow. These samples would have their own latitude/longitude co-ordinates. The four samples would link to a GIS map. 12. Stills and video clips together with text information could be incorporated into a multimedia presentation, to demonstrate the range of level seabed types found along a part of the northern English Channel. More recent images taken during SCUBA diving of reef habitats in the same area as the towed sledge surveys could be added to the Holme images.
Resumo:
Long-term research in the western English Channel, undertaken by the marine laboratories in Plymouth, is described and details of survey methods, sites, and time series given in this chapter. Major findings are summarized and their limitations outlined. Current research, with recent reestablishment and expansion of many sampling programmes, is presented, and possible future approaches are indicated. These unique long-term data sets provide an environmental baseline for predicting complex ecological responses to local, regional, and global environmental change. Between 1888 and the present, investigations have been carried out into the physical, chemical, and biological components (ranging from plankton and fish to benthic and intertidal assemblages) of the western English Channel ecosystem. The Marine Biological Association of the United Kingdom has performed the main body of these observations. More recent contributions come from the Continuous Plankton Recorder Survey, now the Sir Alister Hardy Foundation for Ocean Science, dating from 1957; the Institute for Marine Environmental Research, from 1974 to 1987; and the Plymouth Marine Laboratory, which was formed by amalgamation of the Institute for Marine Environmental Research and part of the Marine Biological Association, from 1988. Together, these contributions constitute a unique data series; one of the longest and most comprehensive samplings of environmental and marine biological variables in the world. Since the termination of many of these time series in 1987-1988 during a reorganisation of UK marine research, there has been a resurgence of interest in long-term environmental change. Many programmes have been restarted and expanded with support from several agencies. The observations span significant periods of warming (1921-1961; 1985-present) and cooling (1962-1980). During these periods of change, the abundance of key species underwent dramatic shifts. The first period of warming saw changes in zooplankton, pelagic fish, and larval fish, including the collapse of an important herring fishery. During later periods of change, shifts in species abundances have been reflected in other assemblages, such as the intertidal zone and the benthic fauna. Many of these changes appear to be related to climate, manifested as temperature changes, acting directly or indirectly. The hypothesis that climate is a forcing factor is widely supported today and has been reinforced by recent studies that show responses of marine organisms to climatic attributes such as the strength of the North Atlantic Oscillation. The long-term data also yield important insights into the effects of anthropogenic disturbances such as fisheries exploitation and pollution. Comparison of demersal fish hauls over time highlights fisheries effects not only on commercially important species but also on the entire demersal community. The effects of acute ("Torrey Canyon" oil spill) and chronic (tributyltin [TBT] antifoulants) pollution are clearly seen in the intertidal records. Significant advances in diverse scientific disciplines have been generated from research undertaken alongside the long-term data series.
Resumo:
This document provides details of the transfer of the Norman Holme archive data held in the National Marine Biological Library onto a modern database, specifically Marine Recorder. A key part in the creation of the database was the retrieval of a large amount of information recorded in field notebooks and on loosely-bound sheets of paper. As this work involved amending, interpreting and updating the available information, it was felt that an accurate record of this process should exist to allow scientists of the future to be able to clearly link the modern database to the archive material. This document also provides details of external information sources that were used to enhance and qualify the historical interpretation, such as estimating volumes and species abundances.
Resumo:
MURAWSKI AND COLLEAGUES STATE THAT OUR assessment of the impacts of global marine biodiversity loss is overly pessimistic. They imply that management interventions are likely to reverse current trends of overfishing, and that the U.S. National Marine Fisheries Service (NMFS) has already met that goal. They cite Georges Bank haddock as an example and contest that catch metrics (as used in our global analysis) are sufficient to track the status of this particular fish stock and possibly others. We agree that precise biomass data are preferable, but these are rarely available. Here, we illustrate that catches are a good proxy of the status of haddock, although there can be a short delay in detecting recovery under intense management. While NMFS’s own data show that full recovery is still uncommon (<5% of overfished stocks) (1), we strongly agree that destructive trends can be turned around and that rebuilding efforts need to be intensified to meet that goal. But we must not miss the forest for the trees: Continuing focus on single, well-assessed, economically viable species will leave most of the ocean’s declining biodiversity under the radar.
Resumo:
Efficient searching is crucial for timely location of food and other resources. Recent studies show diverse living animals employ a theoretically optimal scale-free random search for sparse resources known as a Lévy walk, but little is known of the origins and evolution of foraging behaviour and the search strategies of extinct organisms. Here we show using simulations of self-avoiding trace fossil trails that randomly introduced strophotaxis (U-turns) – initiated by obstructions such as ¬¬¬self-trail avoidance or innate cueing – leads to random looping patterns with clustering across increasing scales that is consistent with the presence of Lévy walks. This predicts optimal Lévy searches can emerge from simple behaviours observed in fossil trails. We then analysed fossilized trails of benthic marine organisms using a novel path analysis technique and find the first evidence of Lévy-like search strategies in extinct animals. Our results show that simple search behaviours of extinct animals in heterogeneous environments give rise to hierarchically nested Brownian walk clusters that converge to optimal Lévy patterns. Primary productivity collapse and large-scale food scarcity characterising mass extinctions evident in the fossil record may have triggered adaptation of optimal Lévy-like searches. The findings suggest Lévy-like behaviour has been employed by foragers since at least the Eocene but may have a more ancient origin, which could explain recent widespread observations of such patterns among modern taxa.
Resumo:
Background The seas around Scotland are rich and diverse – Scotland’s position at the edge of the continental shelf, the long coastline, large area of sea and the mixing of warm and coldwater currents combine to make its waters a special place for marine wildlife and habitats. Scotland has over 18,000 km of coastline and its inshore and offshore areas are among the largest of any EU country, representing 13% of all European seas. Scotland’s seas are of outstanding scenic, historical and cultural value and are part of the national identity at home and abroad. The Marine (Scotland) Act 2010 and the UK Marine and Coastal Access Act 2009 include new powers and duties to ensure that our seas are managed sustainably for future generations, integrating the economic growth of marine industries with the need to protect these assets. Measures to conserve Scotland’s marine natural heritage are based on a three pillar approach, with action at the wider seas level (e.g. marine planning or sectoral controls); specific species conservation measures (e.g. improved protection for seals); and through site protection measures - the identification of new Marine Protected Areas (MPAs). To help target action under each of the three pillars, Scottish Natural Heritage (SNH) and the Joint Nature Conservation Committee (JNCC) have generated a focused list of habitats and species of priority conservation importance - the Priority Marine Features (PMFs). The aim of the current study was to produce a descriptive catalogue of the Scottish PMFs (including component habitats and species where appropriate) to serve as a reference for future nature conservation action. Whilst derived from available existing accounts, the succinct 1-page descriptions are written from a Scottish perspective, refining, but clearly linking to more generic UK, EC or OSPAR (Oslo and Paris Commission) commentary. Available information on the geographic distribution of the features was collated as part of the project and a summary map is provided in each description. Main findings This project has generated a descriptive catalogue of the 81 PMFs that have been identified in the seas around Scotland (out to the limit of the UK continental shelf). The list comprises 26 broad habitats (e.g. burrowed mud), seven low or limited mobility species (e.g. ocean quahog) and 48 mobile species, including fish (e.g. blue ling) and marine mammals (e.g. minke whale). Information on the distribution of the PMFs was collated within a Geographic Information System (GIS). This is the first time that data about such a diverse range of Scottish marine nature conservation interests have been compiled within a single repository. These data have and will be used in conjunction with other contextual base-mapping to inform the development of nature conservation advice and commentary (e.g. in the production of the Scotland’s Marine Atlas - Baxter et al., 2011). The feature distribution mapping used in the production of this report is being made available to view online via the National Marine Plan Interactive web portal (NMPi - http://www.gov.scot/Topics/marine/seamanagement/nmpihome). As new or refined data on Scottish PMFs become available, these will be fed into updates to the project geodatabase and NMPi.
Resumo:
Background The seas around Scotland are rich and diverse – Scotland’s position at the edge of the continental shelf, the long coastline, large area of sea and the mixing of warm and coldwater currents combine to make its waters a special place for marine wildlife and habitats. Scotland has over 18,000 km of coastline and its inshore and offshore areas are among the largest of any EU country, representing 13% of all European seas. Scotland’s seas are of outstanding scenic, historical and cultural value and are part of the national identity at home and abroad. The Marine (Scotland) Act 2010 and the UK Marine and Coastal Access Act 2009 include new powers and duties to ensure that our seas are managed sustainably for future generations, integrating the economic growth of marine industries with the need to protect these assets. Measures to conserve Scotland’s marine natural heritage are based on a three pillar approach, with action at the wider seas level (e.g. marine planning or sectoral controls); specific species conservation measures (e.g. improved protection for seals); and through site protection measures - the identification of new Marine Protected Areas (MPAs). To help target action under each of the three pillars, Scottish Natural Heritage (SNH) and the Joint Nature Conservation Committee (JNCC) have generated a focused list of habitats and species of priority conservation importance - the Priority Marine Features (PMFs). The aim of the current study was to produce a descriptive catalogue of the Scottish PMFs (including component habitats and species where appropriate) to serve as a reference for future nature conservation action. Whilst derived from available existing accounts, the succinct 1-page descriptions are written from a Scottish perspective, refining, but clearly linking to more generic UK, EC or OSPAR (Oslo and Paris Commission) commentary. Available information on the geographic distribution of the features was collated as part of the project and a summary map is provided in each description. Main findings This project has generated a descriptive catalogue of the 81 PMFs that have been identified in the seas around Scotland (out to the limit of the UK continental shelf). The list comprises 26 broad habitats (e.g. burrowed mud), seven low or limited mobility species (e.g. ocean quahog) and 48 mobile species, including fish (e.g. blue ling) and marine mammals (e.g. minke whale). Information on the distribution of the PMFs was collated within a Geographic Information System (GIS). This is the first time that data about such a diverse range of Scottish marine nature conservation interests have been compiled within a single repository. These data have and will be used in conjunction with other contextual base-mapping to inform the development of nature conservation advice and commentary (e.g. in the production of the Scotland’s Marine Atlas - Baxter et al., 2011). The feature distribution mapping used in the production of this report is being made available to view online via the National Marine Plan Interactive web portal (NMPi - http://www.gov.scot/Topics/marine/seamanagement/nmpihome). As new or refined data on Scottish PMFs become available, these will be fed into updates to the project geodatabase and NMPi.
Resumo:
As the UK's national marine data centre, a key responsibility of the British Oceanographic Data Centre (BODC) is to provide data management support for the scientific activities of complex multi-disciplinary long-term research programmes. Since the initial cruise in 1995, the NERC funded Atlantic Meridional Transect (AMT) project has undertaken 18 north–south transects of the Atlantic Ocean. As the project has evolved there has been a steady growth in the number of participants, the volume of data, its complexity and the demand for data. BODC became involved in AMT in 2002 at the beginning of phase II of this programme and since then has provided continuous support to the AMT and the wider scientific community through the rescue, quality control, processing and access to the data. The data management is carried out by a team of specialists using a sophisticated infrastructure and hardware to manage, integrate and serve physical, biological and chemical data. Here, we discuss the approach adopted, techniques applied and some guiding principles for management of large multi-disciplinary programmes.