bluuebunny/crossref_metadata_2025 huggingface dataset:
Conserving the freshwater pearl mussel (Margaritifera margaritifera L.) in the British Isles and Continental europe
Authors: Young Mark R.
Published: February 2007

1. This paper reviews the status of the freshwater pearl mussel (Margaritifera margaritifera L.) in the British Isles and Continental Europe.

2. The mussel has continued to decline in recent decades throughout the European range, apparently caused mainly by pollution (especially by organic enrichment) and, in the British Isles, by a combination of this and overfishing for pearls.

3. Of particular concern is the almost complete absence of juveniles in most populations, with these occurring in numbers only in a very few rivers in remote locations.

4. M. margaritifera is now completely protected in most European countries and in Britain the government has recently made it an offence to kill or harm the mussel. However, it will still be permitted to take the mussel, examine it carefully for pearls, and then to return it unharmed to the river. This may prove difficult to enforce and it is concluded that it will be ineffective and that complete protection may still be needed.

5. There is no current monitoring programme for M. margaritifera anywhere in its range and without continuing evidence on its status and further research on the habitat requirements of the juveniles, it is difficult to be optimistic about its survival.
The brackish ponds at Killingholme, Humberside, UK
Authors: Bamber R. N. , Batten S. D. , Bridgwater N. D.
Published: February 2007

1. The National Power site at Killingholme, on the Humber Estuary, contains three brackish ponds at the northeast corner, adjacent to Killingholme Haven. The ecology and conservation importance of these ponds were surveyed as part of a Nature Conservancy Council lagoon research programme in 1986 and by National Power staff in 1990 and 1991.

2. The north and west ponds were found to be saline, and both supported the nationally rare polychaete worm Alkmaria romijni. The east pond was fragmenting, owing to the incursion of the reed Phragmites australis, and predominantly freshwater.

3. A total of nine characteristic lagoonal species was present in the system.

4. In 1990 the saline ponds had been allowed to dry out extensively, which was detrimental to the lagoonal species.

5. The surveys concluded that the system of ponds is of national importance for conservation on account of its invertebrate community, particularly with the diversity of lagoonal habitat it offers. Optimum management of the system for conservation is discussed.
Conservation of freshwater fish in the British Isles: the status of fish in national nature reserves
Authors: Lyle Alex A. , Maitland Peter S.
Published: February 2007

1. To consider fully the conservation management of freshwater fish, it was important to know which fish were already in the protected environment of National Nature Reserves (NNRs) — the principal sites for nature conservation in Great Britain. For this reason, 235 NNRs declared by the Nature Conservancy Council (NCC) were surveyed for freshwater fish between 1987 and 1990 by questionnaires to the wardens, by compiling data from other sources, and, where necessary, by field sampling. The presence of fresh waters (as lakes, ponds, rivers and streams) was also recorded. The survey was organized to follow the country and regional structure by which nature conservation was administered by the NCC so that the results could be considered accordingly.

2. Seventy five percent of NNRs contain fresh waters and, of these, just over 20% have no fish. Of the 51 fish species available 37 (73%) were recorded in NNRs. NCC regions with most fish species are: SW Scotland, West Midlands and East Anglia, but NW Scotland has the highest total of species occurrences in NNRs. In terms of both the numbers of species and their frequency of occurrence, NW and NE England are notably the lowest. The most common fish in NNRs are Eels, Brown Trout and Three‐spined Sticklebacks.

3. The results for species and for sites (NNRs) are discussed from the viewpoint of fish conservation. The majority of fish in NNRs are those most common in Great Britain. Two of the species recorded (Powan and Smelt) are currently important for conservation, but several of those most threatened do not occur in NNRs. A number of NNRs have diverse fish communities, but only six have significant fish conservation value, of which Loch Lomond NNR is outstanding.

4. There is considerable scope through NNR management to improve fish conservation and it is suggested that the acquisition of new reserves for threatened species should be considered.
Channelling scientific information for the conservation and management of rivers
Authors: Boon P. J.
Published: February 2007

1. This paper discusses the characteristics of scientific information used in river conservation and management.

2. Information should be appropriately focussed, achieving a balance between the ideal and the achievable, recognizing the functioning of river basins and not merely river channels.

3. Technical data need to be presented in a way that is readily understood by decision‐makers — simply, but not simplistically. This is discussed using examples such as river corridor mapping and the application of numerical indices of water quality and conservation value.

4. Ideally, river management policy and practice requires a scientific input that is both unequivocal and authoritative. Frequently, however, disagreement over its interpretation delays information transfer.

5. The results of applied studies in freshwater science are not always as accessible as they should be to river managers. Once acquired there must be a genuine willingness by planners to incorporate the results of ecological research into project design, a process often hindered by complex bureaucratic structures. It is thus argued that operational flexibility in river management schemes is desirable, and post‐project appraisal essential.
A botanical classification of standing waters in Britain: Applications for conservation and monitoring
Authors: Palmer M. A. , Bell S. L. , Butterfield I.
Published: February 2007

1. A classification is described based on an indicator species analysis of the vegetation of 1124 fresh and brackish standing water sites in Great Britain.

2. Ten Site Types are recognizable by their assemblages of plants, and these groupings are related to the alkalinity, pH and conductivity of the water. One Type consists of extremely acid water bodies on peat. There are two other nutrient‐poor Types, distinguishable from each other largely by size and substrate, as well as by vegetation. These sites lie mostly in the north and west of Britain. There are four distinct Site Types with nutrient‐rich water, one characteristic of Scotland, the rest more typical of the lowlands of southern and eastern Britain. A further Site Type is regarded as mesotrophic and is found mainly in northern England and Scotland. Of the remaining two Site Types, one shows an unusual combination of base‐poor and base‐rich characteristics and the other comprises brackish sites in Scotland.

3. The use of the classification for producing Trophic Ranking Scores, both for individual species and for sites, and the application of these scores for monitoring the nutrient status of fresh waters are explained.

4. The application of the classification to the selection of sites important for nature conservation is discussed, with special reference to north west Scotland.

5. This classification is compared with other classifications of aquatic vegetation in Great Britain.
Effects of large woody debris removal on physical characteristics of a sand‐bed river
Authors: Douglas Shields F. , Smith Roger H.
Published: February 2007

1. Removal of large woody debris (LWD) is one of the most widely practised stream alterations, particularly in sand‐bed rivers of the south‐eastern USA. Selective removal of LWD has been proposed as an alternative to orthodox non‐selective clearing in order to conserve ecological resources, but methods for comparing hydraulic and environmental effects of selective and non‐selective removal have not been developed. Conservation of stream habitats requires quantification of LWD removal impacts on physical habitat.

2. Physical characteristics of straightened, sand‐bed reaches of the South Fork Obion River in western Tennessee, USA that were rich in LWD were compared with those in similar reaches where debris had recently been removed using selective removal guidelines.

3. The mean volume of LWD per unit water volume was 0.0545 in the uncleared reaches, but nearly 60% lower (0.0225) in the cleared reach.

4. A simple technique for predicting hydraulic roughness in channels with varying amounts of LWD was developed. Hydraulic roughness, as measured by the Darcy‐Weisbach friction factor, was about 400% greater in uncleared reaches at base flow but declined to a level about 35% greater than for the cleared reaches at higher flows. Predicted friction factors were within 35% of measured friction factors at higher flows.

5. Physical habitat diversity in this channelized sand‐bed stream was strongly related to the density of LWD. Flow conditions in the uncleared reaches were more heterogeneous than in the cleared reach, especially at low flow. At low flow, uncleared reaches tended to be shallower, have lower velocities, slightly finer bed material, and more heterogeneous conditions overall. Shannon indices based on depth and velocity were an average of 48% higher in uncleared reaches.

6. Bed sediments underneath and immediately adjacent to LWD formations were finer and contained more organic matter than sediments distant from LWD. However, when all bed samples were considered, organic content was positively correlated with median grain size.
Conservation of freshwater fish in the British Isles: Proposals for management
Authors: Maitland Peter S. , Lyle Alex A.
Published: February 2007

1. Recent checklists of the freshwater fish of the British Isles have included 42 native and 13 introduced species. Of the former, however, two are extinct now and eight are threatened in various ways. In addition there are several important stocks of common native species under threat.

2. Protection for British fish exists mainly through legislation and protected sites of various designations. The legislation is inadequate in some respects and very few of the protected sites were actually established for their fish interest. Nevertheless, in Great Britain, 37 species of fish occur in National Nature Reserves. The overall status of fish in Sites of Special Scientific Interest is unknown.

3. The main conservation options for managing freshwater fish resources are habitat restoration, stock transfer to new sites, captive breeding and cryopreservation. The first two of these are regarded as the most useful for the long‐term conservation of threatened species. Improved legislation would also help, especially in relation to preventing the import and transfer of potentially harmful species.

4. As well as the implementation of conservation management programmes for rare fish, research and monitoring studies are also needed in order to aid management and maintain a watch on populations of important species. In addition, national fish databases and registers of important stocks are an important background for overall fish conservation and management.
The impact of land‐claim on macrobenthos, fish and shorebirds on the forth estuary, eastern Scotland
Authors: McLusky Donald S. , Bryant David M. , Elliott Michael
Published: February 2007

1. The impact of land‐claim on the intertidal areas of the Forth estuary, eastern Scotland is described. It is shown that in recent times almost 50% of the intertidal area has been destroyed for a variety of purposes, including agriculture, harbours and industrial development.

2. The loss of infaunal invertebrate biomass and production from the intertidal habitat has been calculated for each part of the estuary, and by summation for the whole estuary. The loss is discussed in relation to the total biomass and production, both intertidally and subtidally, of the estuary. It is shown that proportionately more biomass and production may have been lost than area.

3. The impact of land‐claim on estuarine fish is calculated. Land‐claim has removed 24% of the natural fish habitats in the Forth estuary, and thereby removed 40% of their food supply.

4. The impact of habitat loss on birds was observed for one area where observations continued throughout a period of land‐claim. For individual bird species at Torry Bay, land‐claim had consequences ranging from neutral to substantially negative. Significant declines were found for overwintering populations of dunlin and bar‐tailed godwit. Comparisons of pre‐ and post‐land‐claim bird feeding usage of this area, showed that the impact of land‐claim on local bird populations differed between species. The large scale loss of habitat on the Forth seems likely to have reduced the size of some shorebird populations which overwinter on the estuary.

5. It is concluded that when considering the impact of land‐claim on estuaries that, as found in some previous studies, a simple consideration of area lost may be inadequate to describe the effects of land‐claim, and the consequences for animals living within the estuary may differ considerably amongst themselves and from area to area.
A survey of pond loss in Essex, South‐east England
Authors: Heath D. J. , Whitehead A.
Published: February 2007

1. Sample areas of the county were used to estimate pond loss. An extensive survey used only maps while a smaller, intensive survey combined maps with a field study. In total, 283.43 km2 were surveyed, approximately 7% of the total area.

2. Fifty‐five per cent of the ponds present in 1870 had disappeared by 1960 with the greatest loss occurring between 1920 and 1960.

3. Loss of ponds in agricultural locations contributed most to this because of their high initial number and their high rates of loss. Percentage losses of large and small ponds were greater than for medium‐sized ponds.

4. A field survey showed that a further 23% of a random sample of ponds shown on maps of 1960 could not be found in 1989. Overall loss rates for the period 1870–1989 are estimated to be 68.6% for the extensive area and 54.8% for the intensive area.
Management of the exploitation of the lugworm Arenicola marina and the ragworm Nereis virens (Polychaeta) in conservation areas
Authors: Olive P. J. W.
Published: February 2007

In Europe, bait supply to anglers from the natural environment involves: (i) bait collection by anglers for own use, (ii) local semi‐professional bait digging and (iii) professional bait digging contracted to distributors.

The management of bait digging activity is particularly acute where there is a conflict with conservation interests.

Two case studies are presented describing the population dynamics of: I Arenicola marina in the Lindisfarne nature reserve, and II Nereis virens in the Menai Strait; both in conservation areas.

Case I. Populations of A marina are subject to marked annual cycles in number and fresh weight. This case illustrates the response of the population to substantial overexploitation leading to a population crash. With the introduction of restrictive legislation the population was re‐established by recruitment of adults from neighbouring unexploited populations.

Case II illustrates the dynamics of a N. virens population dominated by large old individuals; it does not represent a sustainable resource in contrast with populations of the same species in other locations.

The management of the exploitation of bait populations in conservation areas is discussed in relation to world patterns of utilization and supply.
PCBs and organochlorine pesticide residues in otter (Lutra lutra) spraints from Welsh catchments and their significance to otter conservation strategies
Authors: Mason C. F. , Macdonald S. M.
Published: February 2007

A survey is presented of PCB and organochlorine pesticide concentrations in otter (Lutra lutra) spraints (faeces) from 18 catchments/sub‐catchments in Wales and adjacent English counties.

There were wide differences in concentrations of lindane, dieldrin, DDE and PCBs between catchments and at sites within catchments. Only PCBs were considered likely to be of significance in influencing otter populations. Mean PCB concentrations (but not those of dieldrin and DDE) were inversely related to otter population performance (as measured by both catchment distribution and sprainting intensity) between catchments.

It is suggested that PCB contamination is exerting a negative impact on otter populations in four catchments, while there is concern over four others. A study of food chain contamination should be an essential component of otter conservation strategies at both the national and local level.
New Zealand's Resource Management Act and fresh water
Authors: Scott D.
Published: February 2007

This paper describes New Zealand's Resource Management Act in relation to freshwater management and conservation.

The development of the Act is described with reference to the consolidation and integration of earlier legislation. The central concept of sustainable management is more limited than the related concept of sustainable development, and places constraints on activities which have environmental impacts.

The specific provisions relating to fresh water are noted, and the resource consents required for taking water, damming or diverting watercourses, and discharging into water, or onto land where the discharge may reach water, are described. The relation of riparian management to the requirement for protection of fish habitat is noted, and water conservation orders are described. Attention is given to the likely implications for managers.

An attempt is made to anticipate difficulties that may arise in implementing the Act; in particular, the possible balancing between socio‐economic and ecological considerations. The specific features of the freshwater environment are considered from the viewpoint of management, and the problems involved in tradeability are noted. Attention is drawn to the scope of the Act in the attempted integration of most, but not all, environmental considerations, and a final evaluation suggests that economic growth is likely to present a substantial challenge to the purpose of the Act.
Interaction between seals and marine fish‐farms in Tasmania, and management of the problem
Authors: Pemberton D. , Shaughnessy P. D.
Published: February 2007

Seals that attacked fish on 15 marine fish‐farms in south‐eastern Tasmania were large subadult and adult male Australian fur seals Arctocephalus pusillus doriferus. From July to November 1988 there were 235 attacks on fish‐farms where Atlantic salmon Salmo salar and rainbow trout S. gairdneri were held in pens. Single animals usually attacked pens at night, irrespective of the size and species of fish in the pens. The seals damaged both pens and fish, and sometimes fish escaped as a result of the attacks.

The vulnerability of fish‐farms was influenced by their proximity to seal haul‐out sites. Proximity to fishing ports and size of the fish‐farm had little influence.

The use of shooting as a protection method was inefficient and ineffective because seals usually entered fish‐farms at night and showed no fear of shooters. There were many attacks in the presence of underwater acoustic seal scarers. Deterrents such as pursuit with boats, lights, seal crackers and emetics helped reduce the number of seal attacks.

The only way totally to prevent seals from attacking fish‐farms is to exclude them from the vicinity of the fish pens with physical barriers that they cannot penetrate. These are currently in use, and include perimeter fences and protection nets made of steel mesh set around individual pens.
Hierarchical methods and sampling design for conservation monitoring of tropical marine hard bottom communities
Authors: Sullivan K. M. , Chiappone M.
Published: February 2007

A 4‐year study developed methods for annual monitoring of shallow‐water tropical marine benthic communities to detect changes in spatial patterning and benthic diversity. Two low‐relief sponge/octocoral communities were selected from natural colour photography to gain a broader perspective on spatial variability in the benthic community structure of similar community types.

Changes in benthic spatial patterning were studied using four methods: (i) substrata and lifeform coverage characterization, (ii) species inventories, (iii) belt quadrat measurements of taxa‐level (algae, sponges, octocorals and stony corals) density, area coverage and size, and (iv) belt quadrat measurements of species‐level density, area coverage and area per individual or colony.

A sampling hierarchy of multiple parameters was utilized to detect changes in benthic community diversity. Substrata and lifeform characterizations (at the taxa‐versus species‐level) were the least sensitive and serve as indicators of catastrophic change in community structure.

Changes in spatial patterning of the benthos that may be attributed to low‐level, chronic anthropogenic disturbances can be best studied utilizing belt quadrat measurements. The use of multiple study sites and a sampling hierarchy was useful in minimizing Type II errors and to determine the level of monitoring necessary to segregate natural rates of change from anthropogenic impacts.
The effects of human activity on the temporal variability of coral reef fish assemblages in the Key Largo National Marine Sanctuary
Authors: Greene Lawrence E. , Shenker Jonathan M.
Published: February 2007

A visual assessment method, called Discrete Group Censusing, was used to assess and monitor five coral reef fish assemblages in the Key Largo National Marine Sanctuary, Florida, USA.

Samples were obtained quarterly from Winter 1988 to Autumn 1990 to investigate a possible relation between the variability of reef fish assemblages and human disturbance.

Two types of disturbance were studied: a ship grounding that occurred 4 years previous to the study, and intensive, recreational snorkel and SCUBA diving. These disturbances appeared to have no short‐term effect on the temporal variability of the reef fish assemblages during the study period.

Furthermore, the assemblages at all five study sites appeared to be extremely stable over the 2 year period of the study. These results support the theory that coral reef fish assemblages are highly ordered and stable over relatively large spatial scales.

The Discrete Group Censusing visual assessment method was found to be a valuable and easily applied tool for the nondestructive in situ monitoring of reef fish assemblages on coral reefs.
Case studies and reviews. Working towards a marine nature reserve in Jersey
Authors: Culley Michael , Romeril Michael
Published: February 2007

A biological inventory is described for Portelet Bay, on the south coast of Jersey in the Channel Islands, which has been selected for the Island's first marine nature reserve.

The application of site assessment criteria in justifying the selection of the site is discussed.

Conclusions are drawn on the process by which marine reserve status might be achieved.
Case studies and reviews. Vegetation zonation and invertebrate fauna in Pant‐y‐llyn, an unusual seasonal lake in South Wales, UK
Authors: Blackstock T. H. , Duigan C. A. , Stevens D. P. , Yeo M. J. M.
Published: February 2007

Temporary waters have been relatively neglected in British nature conservation, due in part to paucity of survey and comparative assessment. Such water bodies hold distinctive and specialized biological communities, and the need for conservation measures at key localities is increasingly recognized in Europe.

An account of the vegetation and invertebrate fauna in Pant‐y‐llyn, a small temporary lake on Carboniferous Limestone in South Wales, is presented. Water levels in the basin reflect seasonal variation in the height of the local groundwater, and it fills to a depth of ca 3–4 m in winter but is almost completely dry in summer.

There is a clearly displayed sequence of bryophyte, herbaceous swamp and woody plant communities which occupy different depth zones in the basin.

The invertebrate community is dominated by microcrustaceans and a range of insect groups; adaptations for survival over the summer dry phase are considered.

It is concluded that the ecological characteristics and distinctive hydrological features of Pant‐y‐llyn closely resemble those of the Irish turloughs. Pant‐y‐llyn thus represents an important site for conservation as the only known example of this form of seasonal water body in Britain.
A classification of tropical and subtropical Australian estuaries
Authors: Bucher Daniel , Saenger Peter
Published: February 2007

The ability to use large databases to classify estuaries on the basis of any number of characteristics may be valuable in planning a national system of estuarine reserves in Australia which will conserve the range of variability within and between regions.

A recently completed inventory of Australian estuaries and marine embayments has provided quantitative data on a large number of estuaries from which comparisons are made with existing classifications based on qualitative descriptions.

Area measurements are analysed for mangroves, salt marsh/clay pan, seagrass, intertidal flats and open water from 571 tropical and subtropical estuaries north from Carnarvon on the west coast around to Coffs Harbour on the east.

The relative proportions of mangroves and salt marsh within estuaries show strong relationships with average annual rainfall although there are no consistent trends in the absolute area of each wetland type.

The estuaries are classified into three distinct groups on the basis of rainfall and the dominant wetland type.

Greater tide range coincides with a greater area per estuary of all wetland types. As with rainfall, the estuaries fall into three categories of wetland proportions.
An integrated approach to management of coastal aquatic resources—a case study from Jervis Bay, Australia
Authors: Dutton I. M. , Saenger P. , Perry T. , Luker G. , Worboys G. L.
Published: February 2007

The types of pressures evident in coastal regions are typified by the Jervis Bay region in south‐eastern Australia which, despite a long history of human occupation, remains largely undisturbed. How much longer those values and the ecological processes which sustain them will remain viable is questionable.

This paper describes the development of a conservation management strategy which sought an integrated approach to management of the terrestrial and marine resources of the Bay region. A geographical information system (GIS) was developed for the region, using the raster‐based E‐RMS GIS software system.

A continuum of conservation management options for the region was defined, ranging from no change to the presently limited protected area system (which covers only 7.5% of the region), to almost complete reservation. The preferred option, known as the Jervis Bay Conservation Zone, was derived using a landscape ecology approach. This involves a coordinated approach to conservation management by private and public agencies and individuals, with variable levels of control on the use of core habitat and adjacent land/sea areas.

Three specific findings of relevance to the management of coastal aquatic resources elsewhere were that (1) traditional ‘reservation‐based’ approaches to conservation management in isolation are not likely to be effective in conserving biodiversity over time; (2) the planning process should be open for review by non‐technical audiences to facilitate community understanding and support; and (3) GIS can be a very useful tool for data organization and analysis.
Impact of vegetation management on macroinvertebrates in chalk streams
Authors: Armitage P. D. , Blackburn J. H. , Winder J. M. , Wright J. F.
Published: February 2007

Dense growths of macrophytes are a characteristic feature of chalk streams which may cause problems both to farmers and anglers. Weed is frequently cut to reduce flooding of surrounding land and provide open water for anglers.

The objective of this study was to examine short‐term responses of macroinvertebrate faunal assemblages in main flow and marginal samples to both weed‐cutting and the application of herbicide and to compare these with untreated controls.

No statistically significant effect could be demonstrated on such faunal parameters as biotic score, richness and abundance and a multivariate analysis of all available data showed that the weed‐cut and herbicide treated sites could not be distinguished from the control sites III and V on the basis of their fauna.

It is suggested that for conservation purposes small‐scale management with ‘recovery strips’ separating the treated reaches can achieve the desired objectives of avoiding flooding and providing open water for anglers with minimal effects on the river biota.
Conservation strategies for endangered fish breeding and nursery grounds within the coastal wetlands of Nigeria
Authors: Ezenwa B. I. , Ayinla O. A.
Published: February 2007

The Nigerian coastal system—estuaries, lagoons, creeks and wetlands—extends for a distance of approximately 850 km with the Niger Delta (area: 75 000 km2) dominating the entire ecosystem.

Human activities—(oil exploration, haphazard mining of sand from coastal areas, sand filling of wetlands for industrial use, heavy pollution by industries)—severely destroyed the breeding and nursery grounds of commercial fish species between 1973 and 1992.

As a result, fish landings from capture fisheries decreased from 500 000t in the late 1980s to the present 300 000t.

With the Nigerian population increasing at a rate of 3%–4% per year, there is an urgent need for the Federal Government to protect the 850 km coastline, and the riverine wetlands.

Conservation education should be vigorously pursued on the socio‐economic benefits of coastal and riverine wetlands.

The Federal Government should encourage States and Local Governments to enact environmental laws and regulations. Stiff penalties for violations should be vigorously enforced.

Companies involved in exploitation and manufacturing in coastal areas should increase their funding of research directed at minimizing oil spillages and discharge of wastes in their areas of operation.
Monitoring megabenthic communities in abyssal manganese nodule sites of the East Pacific Ocean in association with commercial deep‐sea mining
Authors: Bluhm Hartmut
Published: February 2007

Marine mining of manganese nodules will affect the deep sea benthos in a harmful and longterm way. The near complete removal of manganese nodules will result in a change of the megabenthic community from one that is rich in both diversity and density to a soft bottom community with greatly reduced diversity.

Pre‐pilot mining tests and pilot mining operations, which have to demonstrate the feasibility of deep‐sea mining, should be accompanied by environmental impact studies before commercial mining begins.

The photographic assessment of megabenthic communities represents one cost‐effective possibility of monitoring large‐scale impacts on the deep sea floor. A method based on the analysis of video and photomaterial was used to obtain basic data on community structure and density of the abyssal megabenthos of undisturbed manganese nodule sites in the North (Clarion‐Clipperton Fracture Zone) and South (Peru Basin) Pacific Ocean.

A comparison of the results with data from the literature demonstrates that the different methods used result in different density values.

Total density varied between less than 300 to more than 1600 individuals/10000 m2.

There is a clear need for standardization of methods. A system which combines video and photographic capabilities is useful. It will give the best results when the distance of the camera to the sea floor is between 2 and 3 m, and the area covered by one photograph is within 3 to 5 m2.
Marine reserves in fisheries management
Authors: Rowley R. J.
Published: February 2007

This paper summarizes research on the uses of marine reserves for fisheries management. Examples emphasize temperate marine reserves.

Marine reserves commonly support higher densities and larger sizes of heavily fished species than are found outside reserves.

‘Spillover’ of individuals across reserve borders is likely to augment local catches. There are good reasons to expect such spillover, and there is limited direct evidence for it. However, the magnitude of any resulting increase in local catches will be difficult to predict.

‘Larval export’ from reserves has potential to augment recruitment over large regions, but its success will depend upon many factors that are difficult to predict. No studies have clearly tested the effects of larval export.

To design more effective marine reserves, studies are needed of the movement patterns and habitat requirements of all life stages (larval, settlement, juvenile, adult, feeding, and breeding) of targeted species.

To determine clearly the effects of marine reserves on fisheries requires replicated before/after studies.
Restoration of a channelized reach of the River Gelså, Denmark: Effects on the macroinvertebrate community
Authors: Friberg Nikolai , Kronvang Brian , Svendsen Lars M. , Hansen Hans Ole , Nielsen Mogens B.
Published: February 2007

The restoration of a 1.3 km straightened and channelized reach of the River Gelså to a new 1.9 km meandering course is one of the largest river restoration projects so far undertaken in Denmark. In order to elucidate the ecological impact of restoration, the macroinvertebrate community present in the reach prior to and following its restoration was compared with that in an upstream reach that remained straight and channelized.

Two years after restoration of a meandering course, macroinvertebrate density and diversity was greater than in the upstream control reach, Gammarus pulex L. being particularly abundant in the restored reach. In general, species preferring a stony habitat seemed to favour the new reach; Heptagenia sulphurea Müll. was only found on stones in the restored reach, and was totally absent from the control reach. Two other stone‐preferring species, Ancylus fluviatilis Müller and Hydropsyche pellucidula Curtis, were found in higher density in the control reach; however, this probably reflects competition for the limited space available on stones.

The study shows that river restoration can have a positive impact on macroinvertebrate community structure, and probably higher trophic levels also, such as fish, due to increased numbers of potential prey organisms. In addition, the study suggests that the impact of restoration projects on the macroinvertebrate community is best understood by undertaking both qualitative and quantitative studies.
Fluvial maintenance operations in managed alluvial rivers
Authors: Darby Stephen E. , Thorne Colin R.
Published: February 2007

Fluvial maintenance is frequently undertaken to preserve the flood capacity, visual amenity, conservation value and geomorphic stability of managed river channels. Maintenance tasks include the management of both riparian and in‐channel vegetation and maintenance dredging.

Riparian vegetation is traditionally managed by physical methods such as cutting of grasses or removal of trees. Less environmentally severe alternative practices include grazing or shading for grasses, and practices such as pollarding or coppicing for trees.

While a range of alternative maintenance practices, with varying environmental impact, are usually available for river managers to select, the potential for improving maintenance practices varies according to the particular task considered and the constraints imposed by the need to reach and maintain the target standard of service in terms of flood defence and land drainage.

This review shows that economic and environmental impacts associated with fluvial maintenance operations may be reduced at three scales. First, at the smallest scale, it is shown that there is often potential for improving the local operational efficiency of individual fluvial maintenance tasks. Second, it may be possible to reduce the intensity of maintenance in channel reaches which are presently over‐serviced. Third, at the largest scale, it is shown that efficient maintenance is best achieved within the framework of Integrated Basin Management, and by giving appropriate consideration to future maintenance requirements at the design stage of new projects to reduce the overall need for fluvial maintenance. Examples of the way in which these policies may be implemented to reduce environmental impact without compromising engineering objectives are illustrated through case studies from the UK and the USA.
The status and conservation of sharks in Britain
Authors: Vas Philip
Published: February 2007

Despite the ease with which shark stocks can be quickly overfished, illustrated by the collapse of similar fisheries in the past, few regulations currently exist for the effective management of present day fisheries.

Large numbers of sharks are taken by both commercial and recreational fisheries around the British Isles; current landings are reviewed.

These data are used to support the contention that immediate research is undertaken to collect essential life‐history information so that (i) accurate assessments of current stock levels can be made and (ii) a long‐term fishery management plan can be developed.
Pacific oysters crassostrea gigas (Thunberg) of possible French origin in natural spat in the British Isles
Authors: Child A. R. , Papageorgiou P. , Beaumont A. R.
Published: February 2007

Hatchery‐reared Pacific oysters (Crassostrea gigas) grown in the British Isles and Guernsey originate from an introduction through quarantine of small numbers of oysters from British Columbia, Canada.

Previous electrophoretic analysis of samples of these oysters have shown the glucose phosphate isomerase locus to be monomorphic.

Recent analysis of oysters from a commercial hatchery in Guernsey revealed a second allele at low frequencies which was unexpected and was thought to indicate the presence of oysters from another stock.

Samples of hatchery‐reared oysters from France showed that they were highly polymorphic and carried the unexpected allele and four others.

A natural spatfall of oysters from the River Teign (Devon) was sampled and these carried three alleles which were also found in the French C. gigas. This suggests that there has been movement of C. gigas possibly of French origin into this river.

This finding and its implications in terms of conservation and management are discussed.
The greening of the press: A case study of stakeholder accountability and the corporate management of environmentalist publics
Authors: Pinfield Lawrence , Berner Michelle
Published: February 2007

The concept of stakeholder accountability and management is increasingly an integral facet of business strategy. This is particularly evident for companies which have a significant environmental impact, be it real or perceived, where public scrutiny of environmental performance is facilitated through heightened press coverage. Effective stakeholder management therefore necessitates an active response to the media's attention in order to manage the public perception of business activities. This article presents data on the exponential growth in both the total number and the proportion of news articles over the past fifteen years which have associated a large forestry company in Western Canada with environmentalist issues. More detailed analyses of these articles illustrate how environmentalist sub‐issues can be identified and whether the voice is either that of the corporation or the environmentalist movement. Implications of these findings for the management of environmentalist publics is discussed.
Product waste in the automotive industry: Technology and environmental management
Authors: Groenewegen Peter , Hond Frank Den
Published: February 2007

In this article the changes in technology and industry structure forced by waste management in the automotive industry are explored. The analysis is based on (1) a characterisation of corporate response to environmental issues, and (2) the management of technology applied to the car manufacturing industry. It is argued that a more elaborate view of company reactions to governmental regulation of environmental issues has developed in recent years. Companies respond with pro‐active strategies. Because of this active attitude environmental concerns influence other aspects of company policy, such as the management of technology. New strategies emerge which are not only a response to environmental problems, but might also influence the industrial structure for the future. The analysis is not only relevant for the automotive industry, but for other manufacturing industries as well. Government action puts waste management issues on the agenda of an increasing number of manufacturing firms that have to develop solutions for these in close cooperation with their suppliers and customers.
Technological learning and the political shaping of technology: The management of R,D&D of wind and wave power in the UK
Authors: Genus Audley
Published: February 2007

This paper recognises the important role of learning in the process of the shaping or construction of technology. Previous research (e.g. by Collingridge, Genus and Woodhouse) has investigated and suggested ways in which the costs of the inevitable errors made when implementing new or risky technologies may be kept low and the learning obtained subsequently incorporated into the technology in question. In particular, the adoption of trial‐and‐error forms of the gradual implementation of flexible technology has been advocated as a useful decision making strategy for coping with the need to make decisions under uncertainty.

The paper considers the recent history of wind and wave power in the United Kingdom. It examines the extent to which a number of factors related to the process of research, development and demonstration (R,D&D) in these areas have provided stimuli or impediments to such trial‐and‐error implementation and opportunities to learn about the technologies involved. Here, the concept of technological momentum is central to the analysis. The paper is concerned to relate the discussion to the prospects for the development of a renewable energy sector in the UK, capable of competing on reasonable terms with rival conventional or nuclear energy sources. Conclusions drawn concern the extent to which various political and market related factors distort the construction and competitive process, so as to frustrate the technological learning relevant to potentially socially and commercially beneficial energy sources.
Sustainable development: A challenge for dutch industry?
Authors: Tuininga Eric Jan , Groenewegen Peter
Published: February 2007

This paper focuses on the current environmental debate within Dutch society. A major recent development has been the establishment of the National Environmental Policy Plan. In the plan the government recognises that it cannot solve environmental crises through regulation and government measures alone. This paper considers the role of social sectors, and discusses innovation in policy consisting of greater communication with the relevant social actors. The limited reaction of Dutch industry, especially the chemical industry is analysed, and the paper concludes that better tools to measure environmental improvements in industry are needed.
The durability of consumer durables
Authors: Cooper Tim
Published: February 2007

The life span of a product is a key component in assessing its environmental impact. Until very recently, however, product durability was far from prominent in the environmental debate. This has begun to change due to mounting concern about waste, the prospect of producer ‘take back’ schemes and the importance of quality in highly competitive international markets. This has led to product durability emerging on the business and environment agenda.

This paper explores the significance of product life spans and identifies currently available data on the life‐span of consumer durables. It defines product life and argues that, from an environmental perspective, optimum product life, rather than maximum product life should be the goal.

It suggests that potential advantages to businesses of manufacturing and retailing products with longer life spans include improved environmental foresight (i.e. a greater responsiveness to new social trends, changes in consumer behaviour and tighter government regulations), an enhanced reputation for quality, greater potential market share and increased customer loyalty.

Addressing claims that manufacturers deliberately make products with the intention that they should have life spans below the known technical potential, the paper identifies some of the influences upon manufacturers which encourage shorter product life spans. Finally, some means by which longer life products might be encouraged are proposed.
The packaging industry is not carried away by public opinion
Authors: Biod Alexandra , Probert Jane , Jones Cliff
Published: February 2007

The size and composition of our bin has changed over the years, as a result of the evolution of our way of living and our consumption habits. The wider range of goods now offered to consumers has resulted in significant augmentation of waste discarded in the form of packaging. The latter is estimated to represent about 30% by weight of total domestic waste. More than ever concerned about environmental issues, the public, alarmed by the media, has shown a strong interest in the problem of waste and waste management. Packaging is now felt as excessive, wasteful and bad for the environment, in particular plastic packaging since plastics are not as easily recycled as other materials. This paper, which includes the results of a consumer survey, brings to light the attitude and misconception of European consumers towards packaging and packaging materials and gives another insight into the problem.
Business and the genesis of the European Community carbon tax proposal
Authors: Ikwue Tony , Skea Jim
Published: February 2007

The purpose of this paper is to examine the role of business in the regulatory process associated with the carbon tax proposal. The first part of the paper describes the Community's climate change policy, noting first the essential features of Community environment policy‐making, the role of consultation with industry and the significance of the ‘subsidiarity’ principle. This part of the paper moves on to examine the carbon tax proposal and its evolution since 1990. The second part of the paper addresses the specific role which business played in influencing the development of the carbon tax proposal. The general strategy of business was to block the proposal entirely. The paper identifies the potential impacts of the tax on business, implications for corporate strategies and the specific channels through which business influenced the tax proposal, by participating in public debates, through representations to different directorates of the European Commission or by making a case to national authorities. The final part of the paper attempts to draw some lessons about: the business position in relation to large scale environmental problems such as climate change; business responses to economic instruments such as the carbon/energy tax; and the wider relationship between public authorities and business in regulatory processes. The question of whether this relationship has entered a new phase or whether there is still ‘business as usual’ is addressed.