The conservation of British North Sea estuaries

Estuaries are amongst the most productive, but scarce, ecosystems in the world. Britain and the southern North Sea have many and extensive estuaries. Many British North Sea coast estuaries are nationally and internationally important for nature conservation for their variety of sand-dune, saltmarsh, sandflat and mudflat habitats, and the plants and animals that they support. The wildlife of estuaries are currently being affected by a great many of man's activities. Many, particularly land-claim, pollution and recreational activities cause loss and damage to this scarce wildlife habitat. Conservation of British estuaries is achieved mainly through site safeguard — the notification of Sites of Special Scientific Interest (SSSIs) and declaration of National Nature Reserves (NNRs) by the Nature Conservancy Council (NCC), and the designation of sites of international importance under the Ramsar Convention and the EC Directive on Wild Birds — and the amelioration of existing damage by sensitive management and pollution control. Several nationwide surveys, particularly NCC's Estuaries Review, are underway in Britain. These will provide sound comparable information on all estuarine sites, and will form the basis for developing an overall estuarine conservation strategy.     

Juvenile salmon in estuaries: comparisons between North American Atlantic and Pacific salmon populations

All anadromous fishes, including juvenile salmon, encounter estuarine habitats as they transition from riverine to marine environments. We compare the estuarine use between juvenile Atlantic salmon (Salmo salar) in the Penobscot River estuary and Pacific salmon (Oncorhynchus spp.) in the Columbia River estuary. Both estuaries have been degraded by anthropogenic activities. Atlantic and Pacific salmon populations in both basins rely heavily on hatchery inputs for persistence. Pacific salmon, as a group, represent a continuum of estuarine use, from species that move through rapidly to those that make extensive use of estuarine habitats. While Atlantic salmon estuarine use is predominantly similar to rapidly moving Pacific salmon, they can exhibit nearly the entire range of Pacific salmon estuarine use. Both slow and rapidly migrating Atlantic and Pacific salmon actively feed in estuarine environments, consuming insect and invertebrate prey. Interactions between juvenile salmon and estuarine fish communities are poorly understood in both estuaries, although they experience similar avian and marine mammal predators. Estuaries are clearly important for Atlantic and Pacific salmon, yet our understanding of this use is currently insufficient to make informed judgments about habitat quality or overall estuary health. This review of salmonid migration through and residency within estuaries identifies actions that could hasten restoration of both Atlantic and Pacific salmon populations.     

Documenting the Density of Subtidal Marine Debris across Multiple Marine and Coastal Habitats

Marine debris is recognised globally as a key threatening process to marine life, but efforts to address the issue are hampered by the lack of data for many marine habitats. By developing standardised protocols and providing training in their application, we worked with >300 volunteer divers from 11 underwater research groups to document the scale of the subtidal marine debris problem at 120 sites across >1000 km of the coast of NSW, Australia. Sampling consisted of replicated 25×5 m transects in which all debris was identified, counted, and, where appropriate, removed. Sites ranged from estuarine settings adjacent to major population centres, to offshore islands within marine parks. Estuaries and embayments were consistently found to be the most contaminated habitats. Fishing-related items (and especially monofilament and braided fishing line) were most prevalent at the majority of sites, although food and drink items were important contributors at sites adjacent to population centres. The results identified damaging interactions between marine debris and marine biota at some key locations, highlighting the need for management intervention to ensure habitat sustainability. This study reinforces the important contribution that volunteers can make to assessing conservation issues requiring broad-scale data collection. In this case, citizen scientists delivered data that will inform, and help to prioritise, management approaches at both statewide and local scales. These initial data also provide an important baseline for longer-term, volunteer-based monitoring programs.     

Global Invasions of Marine and Estuarine Habitats by Non-Indigenous Species: Mechanisms, Extent, and Consequences

Non-indigenous species (NIS) are increasingly conspicuous inmarine and estuarine habitats throughout the world, as the number,variety, and effects of these species continue to accrue. Mostof these NIS invasions result from anthropogenic dispersal.Although the relative importance of different dispersal mechanismsvaries both spatially and temporally, the global movement ofballast water by ships appears to be the largest single vectorfor NIS transfer today, andmany recent invasions have resultedfrom this transfer. The rate of new invasions may have increasedin recent decades, perhaps due to changes in ballast water transport.Estuaries have been especially common sites of invasions, accumulatingfrom tens to hundreds of NIS per estuary that include most majortaxonomic and trophic groups. We now know of approximately 400NIS along the Pacific, Atlantic and Gulf coasts of the U.S.,and hundreds of marine and estuarine NIS are reported from otherregions of the world. Although available information about invasionsis limited to a few regions and underestimates the actual numberof NIS invasions, there are apparent differences in the frequencyof NIS among sites. Mechanisms responsible for observed patternsamong sites likely include variation in supply of NIS, and perhapsvariation in properties of recipient or donor communities,butthe role of these mechanisms has not been tested. Although ourpresent knowledge about the extent, patterns and mechanismsof marine invasions is still in its infancy, it is clear thatNIS are a significant force of change in marine and especiallyestuarine communities globally. Taxonomically diverse NIS arehaving significant effects on many, if not most, estuaries thatfundamentally alter population, community, and ecosystems processes.The impacts of most NIS remain unknown, and the predictabilityof their direct and indirect effects remains uncertain. Nonetheless,based upon the documented extent of NIS invasions and scopeof then effects, studies of marine communities that do not includeNIS are increasingly incomplete     

Habitat quality of estuarine nursery grounds: Integrating non-biological indicators and multilevel biological responses in Solea senegalensis

Estuaries are highly valuable ecosystems that provide various goods and services to society, such as food provision and supporting nursery habitats for various aquatic species. Estuarine habitat quality assessment is thus critical in managing both ecological and economic value. In this work, various biological and non-biological indicators of habitat quality in estuarine nursery areas were determined, encompassing local environmental conditions, chemical contamination, anthropogenic pressures, juvenile Solea senegalensis condition, biomarkers response to contamination and juvenile density. The various indicators provided an integrated view on habitat quality and their responses were broadly concordant. Nursery quality assessment based on anthropogenic pressure indicators and fish biomarker responses were very similar, signaling nursery areas with higher anthropogenic pressure in Tejo and Ria de Aveiro estuaries. Yet, favorable environmental conditions across all sites could have contributed to lessen the potential hazardous biological effects of exposure to anthropogenic stressors, resulting in soles’ fairly good condition and generally high juvenile density. Nevertheless, a mismatch between high juvenile density and high estuarine contribution to adult coastal populations was observed in areas with higher anthropogenic pressures. Although a causal relationship cannot be established, the results emphasize the need to fully understand how the estuarine period spent in estuaries and local processes determine the quantity and quality of juveniles exported to marine adult populations, which is critical to achieve the full potential of the fish production service of estuaries and coastal stock replenishment.     

Dungeness–a national nature conservation perspective

DOODY, P., 1989. Dungeness–a national nature conservation perspective . Vegetated shingle structures in Great Britain are very restricted in number and almost all examples are of some value for nature conservation. Most of the major sites are of geomorphological significance and have important plant and animal communities. Many of these have been adversely affected by man, mainly through gravel extraction and building.
Dungeness is the single largest area and has suffered more extensive and intensive developments than ony other. Despite this, it remains the most important site for stable vegetated shingle with its associated animals (notably invertebrates), and is an important geomorphological feature.     

Distribution of thermophilic endospores in a temperate estuary indicate that dispersal history structures sediment microbial communities

Endospores of thermophilic bacteria are found in cold and temperate sediments where they persist in a dormant state. As inactive endospores that cannot grow at the low ambient temperatures, they are akin to tracer particles in cold sediments, unaffected by factors normally governing microbial biogeography (e.g., selection, drift, mutation). This makes thermophilic endospores ideal model organisms for studying microbial biogeography since their spatial distribution can be directly related to their dispersal history. To assess dispersal histories of estuarine bacteria, thermophilic endospores were enriched from sediments along a freshwater‐to‐marine transect of the River Tyne in high temperature incubations (50°C). Dispersal histories for 75 different taxa indicated that the majority of estuarine endospores were of terrestrial origin; most closely related to bacteria from warm habitats associated with industrial activity. A subset of the taxa detected were marine derived, with close relatives from hot deep marine biosphere habitats. These patterns are consistent with the sources of sediment in the River Tyne being predominantly terrestrial in origin. The results point to microbial communities in estuarine and marine sediments being structured by bi‐directional currents, terrestrial run‐off and industrial effluent as vectors of passive dispersal and immigration.     

The ecology of the sandy estuaries of North Devon and Carmarthen Bay

The estuaries of the Taf, Tywi, Gwendraeth and Loughor (Carmarthen Bay, South Wales), and the Taw and Torridge (North Devon) were surveyed during the spring and summer of 1988, as part of a four year study of harbours, rias and estuaries in southern Britain commissioned by the Nature Conservancy Council. The aims of these surveys were to describe the major marine habitats and communities present in each estuary, and to assess their nature conservation importance. This paper outlines the results of these surveys, concentrating on the many environmental similarities between the six estuaries.     

如何在北京充分实现受胁鸟类栖息地保护?

实现有效生物多样性保护的关键在于提升生物多样性丰富的人口密集区的保护效率。北京人口密集且生物多样性丰富, 存在3类具有生态保护功能的区划——自然保护区、生态保护红线和限制建设线。上述区域可视为生态保护潜力区。本文以在北京有分布的30种受胁鸟类为主要对象, 探讨现有生态保护潜力区对这些物种栖息地的覆盖程度, 并对如何改善上述受胁鸟类栖息地的保护状况进行了建议。根据物种对栖息地的选择, 基于高分辨率卫星解译的土地利用类型图, 利用最大熵模型(MaxEnt)掩膜栖息地分布图, 得到各受胁鸟类的预测空间分布。叠加这些分布获得北京受胁鸟类丰富度分布格局并进行验证。依据物种丰富度高低, 将受胁鸟类栖息地划分为一至四级(最重要的栖息地是一级栖息地, 以此类推)。同时, 依据地表覆盖类型和人类活动强度高低将北京市域划分为城市建成区、乡村生境区和自然生境区。分别计算3类保护潜力区对上述3类区域以及四级栖息地的覆盖面积比例。结果表明: (1) 95.64%的一级关键栖息地和86.32%的二级关键栖息地分布在乡村生境区, 但仅有0.69%和15.15%的乡村生境区分别被自然保护区和生态保护红线覆盖; (2)未受到自然保护区和生态保护红线覆盖的一、二级关键栖息地主要为水域和沼泽地等湿地、高覆盖度草地和部分耕地, 以及含有较高比例水体的大型城市绿地。基于以上结果, 我们建议至少在一定区域内试行如下保护措施: (1)严格保护湿地及其周边的高覆盖度草地, 确保面积不减少; (2)维持基本农田规模和粮食种植模式; (3)将乡村生境区位于河道附近的水域、沼泽地、高覆盖草地和灌木林纳入生态保护红线范围; (4)在公园绿地中划定生物多样性保护区; (5)优化平原地区林地结构。以上措施将使北京的受胁鸟类栖息地得到更好保护, 为中国东部人口密集区生物多样性保护提供示范。     

Ecological impacts of non-native Pacific oysters (<Emphasis Type="Italic">Crassostrea gigas</Emphasis>) and management measures for protected areas in Europe

Pacific oysters are now one of the most ‘globalised’ marine invertebrates. They dominate bivalve aquaculture production in many regions and wild populations are increasingly becoming established, with potential to displace native species and modify habitats and ecosystems. While some fishing communities may benefit from wild populations, there is now a tension between the continued production of Pacific oysters and risk to biodiversity, which is of particular concern within protected sites. The issue of the Pacific oyster therefore locates at the intersection between two policy areas: one concerning the conservation of protected habitats, the other relating to livelihoods and the socio-economics of coastal aquaculture and fishing communities. To help provide an informed basis for management decisions, we first summarise evidence for ecological impacts of wild Pacific oysters in representative coastal habitats. At local scales, it is clear that establishment of Pacific oysters can significantly alter diversity, community structure and ecosystem processes, with effects varying among habitats and locations and with the density of oysters. Less evidence is available to evaluate regional-scale impacts. A range of management measures have been applied to mitigate negative impacts of wild Pacific oysters and we develop recommendations which are consistent with the scientific evidence and believe compatible with multiple interests. We conclude that all stakeholders must engage in regional decision making to help minimise negative environmental impacts, and promote sustainable industry development.     

Resource quantity affects benthic microbial community structure and growth efficiency in a temperate intertidal mudflat

Estuaries cover <1% of marine habitats, but the carbon dioxide (CO(2)) effluxes from these net heterotrophic systems contribute significantly to the global carbon cycle. Anthropogenic eutrophication of estuarine waterways increases the supply of labile substrates to the underlying sediments. How such changes affect the form and functioning of the resident microbial communities remains unclear. We employed a carbon-13 pulse-chase experiment to investigate how a temperate estuarine benthic microbial community at 6.5°C responded to additions of marine diatom-derived organic carbon equivalent to 4.16, 41.60 and 416.00 mmol C m(-2). The quantities of carbon mineralized and incorporated into bacterial biomass both increased significantly, albeit differentially, with resource supply. This resulted in bacterial growth efficiency increasing from 0.40 ± 0.02 to 0.55 ± 0.04 as substrates became more available. The proportions of diatom-derived carbon incorporated into individual microbial membrane fatty acids also varied with resource supply. Future increases in labile organic substrate supply have the potential to increase both the proportion of organic carbon being retained within the benthic compartment of estuaries and also the absolute quantity of CO(2) outgassing from these environments.     

Oyster Larvae Settle in Response to Habitat-Associated Underwater Sounds

Following a planktonic dispersal period of days to months, the larvae of benthic marine organisms must locate suitable seafloor habitat in which to settle and metamorphose. For animals that are sessile or sedentary as adults, settlement onto substrates that are adequate for survival and reproduction is particularly critical, yet represents a challenge since patchily distributed settlement sites may be difficult to find along a coast or within an estuary. Recent studies have demonstrated that the underwater soundscape, the distinct sounds that emanate from habitats and contain information about their biological and physical characteristics, may serve as broad-scale environmental cue for marine larvae to find satisfactory settlement sites. Here, we contrast the acoustic characteristics of oyster reef and off-reef soft bottoms, and investigate the effect of habitat-associated estuarine sound on the settlement patterns of an economically and ecologically important reef-building bivalve, the Eastern oyster (Crassostrea virginica). Subtidal oyster reefs in coastal North Carolina, USA show distinct acoustic signatures compared to adjacent off-reef soft bottom habitats, characterized by consistently higher levels of sound in the 1.5–20 kHz range. Manipulative laboratory playback experiments found increased settlement in larval oyster cultures exposed to oyster reef sound compared to unstructured soft bottom sound or no sound treatments. In field experiments, ambient reef sound produced higher levels of oyster settlement in larval cultures than did off-reef sound treatments. The results suggest that oyster larvae have the ability to respond to sounds indicative of optimal settlement sites, and this is the first evidence that habitat-related differences in estuarine sounds influence the settlement of a mollusk. Habitat-specific sound characteristics may represent an important settlement and habitat selection cue for estuarine invertebrates and could play a role in driving settlement and recruitment patterns in marine communities.     

Spatial indicators for nature conservation from European to local scale

The paper presents an overview of the objectives and exemplary results of the FP 5 project “Spatial Indicators for European Nature Conservation” (SPIN). The SPIN project is focused on the development and testing of advanced classification methods and spatial indicators based on multisensor satellite data and GIS to accomplish monitoring and management tasks in the context of Natura 2000 and nature conservation. A representative selection of eight regional test areas covers a pan-European network and allows comparative investigations to provide accepted recommendations for regional and European nature conservation. The selected results of four case studies are presented and discussed. The range of work covers the production of regional and local habitat maps by object-oriented classification, a case-based reasoning method for change detection as a management support tool for planning and regulating local land use, the selection and application of structural indicators for the monitoring of Natura 2000 habitats and the downscaling and disaggregation of soil information. Results and the further implementation of presented methods are discussed in the conclusions.     

Marine protected areas increase resilience among coral reef communities

With marine biodiversity declining globally at accelerating rates, maximising the effectiveness of conservation has become a key goal for local, national and international regulators. Marine protected areas (MPAs) have been widely advocated for conserving and managing marine biodiversity yet, despite extensive research, their benefits for conserving non‐target species and wider ecosystem functions remain unclear. Here, we demonstrate that MPAs can increase the resilience of coral reef communities to natural disturbances, including coral bleaching, coral diseases, Acanthaster planci outbreaks and storms. Using a 20‐year time series from Australia's Great Barrier Reef, we show that within MPAs, (1) reef community composition was 21–38% more stable; (2) the magnitude of disturbance impacts was 30% lower and (3) subsequent recovery was 20% faster that in adjacent unprotected habitats. Our results demonstrate that MPAs can increase the resilience of marine communities to natural disturbance possibly through herbivory, trophic cascades and portfolio effects.     

The distribution of pond snail communities across a landscape: separating out the influence of spatial position from local habitat quality for ponds in south-east Northumberland,UK

Ponds support a rich biodiversity because the heterogeneity of individual ponds creates, at the landscape scale, a diversity of habitats for wildlife. The distribution of pond animals and plants will be influenced by both the local conditions within a pond and the spatial distribution of ponds across the landscape. Separating out the local from the spatial is difficult because the two are often linked. Pond snails are likely to be affected by both local conditions, e.g. water hardness, and spatial patterns, e.g. distance between ponds, but studies of snail communities struggle distinguishing between the two. In this study, communities of snails were recorded from 52 ponds in a biogeographically coherent landscape in north-east England. The distribution of snail communities was compared to local environments characterised by the macrophyte communities within each pond and to the spatial pattern of ponds throughout the landscape. Mantel tests were used to partial out the local versus the landscape respective influences. Snail communities became more similar in ponds that were closer together and in ponds with similar macrophyte communities as both the local and the landscape scale were important for this group of animals. Data were collected from several types of ponds, including those created on nature reserves specifically for wildlife, old field ponds (at least 150 years old) primarily created for watering livestock and subsidence ponds outside protected areas or amongst coastal dunes. No one pond type supported all the species. Larger, deeper ponds on nature reserves had the highest numbers of species within individual ponds but shallow, temporary sites on farm land supported a distinct temporary water fauna. The conservation of pond snails in this region requires a diversity of pond types rather than one idealised type and ponds scattered throughout the area at a variety of sites, not just concentrated on nature reserves. Handling editor: B. Oertli     

Random Forest characterization of upland vegetation and management burning from aerial imagery

Aim The upland moorlands of Great Britain form distinctive landscapes of international conservation importance, comprising mosaics of heathland, acid grassland, blanket bog and bracken. Much of this landscape is managed by rotational burning to create gamebird habitat and there is concern over whether this is driving long‐term changes in upland vegetation communities. However, the inaccessibility and scale of uplands means that monitoring changes in vegetation and burning practices is difficult. We aim to overcome this problem by developing methods to classify aerial imagery into high‐resolution maps of dominant vegetation cover, including the distribution of burns on managed grouse moors. Location  Peak District National Park, England, UK. Methods Colour and infrared aerial photographs were classified into seven dominant land‐cover classes using the Random Forest ensemble machine learning algorithm. In addition, heather (Calluna vulgaris) was further differentiated into growth phases, including sites that were newly burnt. We then analysed the distributions of the vegetation classes and managed burning using detrended correspondence analysis. Results Classification accuracy was c. 95% and produced a 5‐m resolution map for 514 km² of moorland. Cover classes were highly aggregated and strong nonlinear effects of elevation and slope and weaker effects of aspect and bedrock type were evident in structuring moorland vegetation communities. The classification revealed the spatial distribution of managed burning and suggested that relatively steep areas may be disproportionately burnt. Main conclusions Random Forest classification of aerial imagery is an efficient method for producing high‐resolution maps of upland vegetation. These may be used to monitor long‐term changes in vegetation and management burning and infer species–environment relationships and can therefore provide an important tool for effective conservation at the landscape scale.     

Application to the terrestrial vertebrates of Italy of a system proposed by IUCN for a new classification of national Red List categories

The criteria for classification set down in the new system of the IUCN Red List categories were applied to national distribution areas. Application of the new criteria to national distribution areas calls for an estimate of the rate of immigration. Classification was applied to the Italian autochthonous terrestrial vertebrate species that reproduce in Italy (Amphibia, Reptilia, Aves and Mammalia). Species with both marine and land habitats were included, but Cetaceans were excluded. Eighty-eight species of the autochthonous species that reproduce in Italy were classified in the threatened categories at the national level. One of the main purposes of the present classification of the risk of extinction in national distribution areas is to provide the information needed to define global conservation priorities of species present on national territory. The species nationally and/or globally endangered or at lower risk were grouped into four priority classes, on the basis of their reproductive phenology on national territory and the size of temporarily present contingents. Of the 551 species present regularly or seasonally on Italian territory, 149 (27.0%) are in the initial indicative list of conservation priorities.     

Ichthyofaunal assemblages in estuaries: A South African case study

This review places the life-history styles of fishes associated with South African estuaries in a global context and presents a classification system incorporating all the major life-history categories for estuary-associated fish species around the world. In addition, it documents the early life histories of the major fish groups in South African estuaries, with particular emphasis on the differing modes of estuarine utilization by marine, estuarine and freshwater taxa.This review details factors influencing the ichthyofaunal community structure in South African estuaries. The availability of fish for recruitment into an estuary depends primarily upon the distributional range of euryhaline marine and estuarine species, with tropical and temperate taxa showing marked abundance trends. Within a particular biogeographic region, however, estuarine type and prevailing salinity regime have a major influence on the detailed ichthyofaunal structure that develops. There is an increasing preponderance of marine fish taxa when moving from a freshwater-dominated towards a seawater-dominated type of system, and a decline in species diversity between subtropical estuaries in the north-east and cool temperate systems in the south-west. Similar declines in fish species diversity between tropical and temperate estuaries in other parts of the world are highlighted.Fish assemblages in estuaries adjust constantly in response to changing seasons, salinities, turbidities, etc. Despite persistent fluctuations in both the biotic and abiotic environment, the basic ichthyofaunal structure appears to have an underlying stability and to be predictable in terms of the response of individual species to specific conditions. This stability seems to be governed by factors such as the dominance of eurytopic taxa within estuarine assemblages and the robust nature of food webs within these systems. The predictability arises from factors such as the seasonality associated with estuarine spawning cycles and juvenile fish recruitment patterns. These patterns, together with a well-documented resilience to a wide range of physico-chemical and biotic perturbations, appear to be an underlying feature of fish assemblages in estuaries around the world.In contrast to marine fish species, estuary-associated taxa have received little conservation attention. Apart from the designation of protected areas, the main direct means of conserving estuary-associated fish stocks include habitat conservation and controls over fishing methods, effort, efficiency and seasonality. Of these, the conservation of fish habitats, the most important, because healthy aquatic environments invariably support healthy fish populations. The use of estuarine sanctuaries for fish conservation is briefly reviewed, as well as the legislation governing the USA National Estuarine Research Reserve System (NERRS) and the Australian Marine and Estuarine Protected Area (MEPA) system. It is concluded that South Africa requires an expansion of the existing Estuarine Protected Area (EPA) network, as well as the upgrading of selected 'estuarine reserves' where fishing is permitted, into 'estuarine sanctuaries' where no exploitation of biological resources is allowed.     

Use of environmental predictors for vegetation mapping in semi‐arid mountain rangelands and the determination of conservation hotspots

Question: Can we predict the spatial distribution of plant communities in semi‐arid rangelands based on a limited set of environmental variables? Where are priority areas for conservation located? Location: Al Jabal al Akhdar, Sultanate of Oman. Methods: A Classification Tree Analysis (CTA) was used to model the presence/absence of seven rangeland communities and agricultural areas based on seven selected environmental predictor variables. The latter were either obtained from existing digital datasets or derived from a digital elevation model and satellite images, whereas the grazing intensity was spatially modelled with the kernel density estimation technique. The resulting decision rules of a CTA were applied for predictive mapping within the study area (400 km², resolution of 5 m) by means of ENVI's decision tree classifier. Plant communities of natural rangelands were subsequently evaluated to determine priority areas for nature conservation. Results: Altitude, grazing intensity and landform revealed the highest predictive power. Most of the rangelands were predicted as Sideroxylon–Oleetum. The overall classification accuracy was 89%, whereby agricultural areas and the Ziziphus spina‐christi‐Nerium oleander community at wadi sites had no misclassification. Inaccuracies occurred mainly because of low sample numbers and errors in available maps of predictor variables. The highest rank for nature conservation was observed for the Teucrio‐Juniperetum occupying 20% of the study area. Conclusions: Vegetation mapping using CTA is a valuable tool for rangeland monitoring and identification of key representative areas for nature conservation. An extrapolation of the model used might be feasible to regions adjacent to the central Hajar Mountains.     

Evaluation and mapping of the conservation significance of habitats using GIS: an example from Crete, Greece

To ensure the long-term future of NATURA 2000 sites across Europe, effective techniques are required for evaluating and monitoring their conservation significance. This paper describes a GIS-based method that uses multi-criteria evaluation (MCE) to determine the conservation significance of vegetation communities and habitats for a case study of a proposed NATURA 2000 site on the northwest coast of Crete, Greece. The method uses the most frequently used criteria for the selection of priority areas for nature conservation—species and habitat diversity, rarity of species and habitats, naturalness, threat of human disturbance and replaceability. For each community and corresponding habitat type, each criterion was scored according to field data and expert knowledge using a numerical scale. The final conservation score for each community was derived using MCE within a GIS and mapped. The results demonstrated that the method is an effective tool for evaluating and comparing conservation significance and could be applied to other sites across Europe and to monitor change.