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The world‘s biodiversity is currently in rapid decline - Europe being no exception - with as principal cause a human-mediated global change. The Natura 2000 network is an important conservation tool for European biodiversity; it is a network of natural and semi-natural sites within Europe with high heritage values due to the exceptional flora and fauna they contain. Here, we evaluated the coverage of 300 threatened species by the Natura 2000 network, and determined potential factors influencing the designation of sites and the structure of the network within a country (social, ecological and demographic national factors). Our analysis was based on a coverage ratio between the Natura 2000 sites and distribution maps of threatened European species. We showed that the distributions of a large proportion of threatened species of mammals, birds and reptiles considered in our study were highly covered (above 90%) by the current Natura 2000 network, demonstrating that the Natura 2000 network also covers species not listed in the annexes of the Nature Directives. However, our results confirm that a large proportion of threatened species (some of them listed on the European annexes), especially fishes, are currently poorly covered by the Natura 2000 network. The coverage of species likely seemed to be highly related to national demographic factors, i.e. the proportion of the national urban population. Our analysis also suggested that the designation of sites depends too strongly on governmental politics, economic and cultural criteria, and interactions between society and the environment. A more effective process might be necessary to ensure the Natura 2000 network reaches its potential as the most important and comprehensive network of protected areas intended to halt the loss of biodiversity in Europe in the near future.
Reserve sites, threatened species, biodiversity loss, conservation tools
The world‘s biodiversity is currently in rapid decline. In recent decades, this trend has accelerated globally, Europe being no exception. The international community reacted by adopting the Rio de Janeiro Convention on Biological Diversity (CBD) in 1992 (
The goal of the Natura 2000 network is to maintain the biological diversity of environments, while taking into account economic, social, cultural and regional logic of sustainable development. Compared to other nature conservation programs (Ramsar (www.ramsar.org ) and MedWet (www.medwet.org ), the Natura 2000 network can be considered as the main contribution by the European Union (EU) to fulfil the recommendations of the CBD, aiming to establish regional and national systems of protected areas on land (by 2010) and sea (by 2012). Currently, the Natura 2000 network covers almost 18% of the area of the 27 member states (more than 26, 000 sites;
The Natura 2000 network comprises two major site categories, Special Protection Areas (SPAs) and Special Areas for Conservation (SACs). SPAs are sites of conservation value for rare and threatened European bird species designated internationally under the Birds Directive (
While the designation of SPAs is based on the presence of bird species listed in the annexes of the Birds Directive, including a validation stage of the EU, SACs designation (Habitats Directive) is more complex and involves several stages (Evans 2012). Nationally, Natura 2000 sites are selected on the basis of national lists proposed by the member states. For each biogeographical region, the European Commission adopts a list of Sites of Community Importance (SCI) which then become part of the network. Finally, the SCI are designated at the national level as Special Areas of Conservation (SAC) which subsequently undergo implementation measures. Faced to this complex method of establishment, the European Directives did not specify the method of consultation to be followed for reserve site selection. Therefore, management of the Natura 2000 network and the responsibilities of member states remain unclear, and so far have not followed a standardized framework (
Species listed in the annexes of the European Directives depend on the criteria from the European and Member state’s scales. Consequently, several species listed in these annexes are not mentioned on the IUCN Red List and vice versa. However, despite not being the primary aim, the Natura 2000 network might help to protect all threatened species. Here, we were interested in the effectiveness of the Natura 2000 network to cover also non-target, but threatened species [IUCN Red List categories: vulnerable (VU), endangered (EN) or critically endangered (CR)]. We were especially interested in the following questions: Are there differences in the coverage related to countries, taxonomic groups or biogeographical regions? Can the differences between countries be explained by national indicators such as population density, gross domestic product, etc.? Because an arbitrary threshold, such as 10 % of the area, is often assumed to assure an efficient protection to a species (
The distribution areas of threatened species as listed on the IUCN Red List were studied within the Natura 2000 network at the national scale, at the scale of biogeographical regions and at the European scale. For abbreviations of each member state from the European Union we followed the two-letter nomenclature established for internet resources (i.e. FR = France, DE = Germany, etc.). Biogeographical regions were abbreviated as follows: Alpine (ALP), Atlantic (ATL), Black Sea (BLA), Boreal (BOR), Continental (CON), Macaronesian (MAC), Mediterranean (MED), Pannonian (PAN), Steppic (STE).
As marine sites have been implemented very recently, we decided to focus on terrestrial and freshwater Natura 2000 sites. The database from the IUCN Red List (
Among all species, distribution maps are prone to errors. The maps used from the IUCN website (n = 145) are depending on how a species present in a given site when underlying distributional maps was considered. Indeed, because information of species abundance was not available yet from the distribution maps of the IUCN website, the species present in a given site could be constantly present, or promptly present (for example present during the migration, for reproduction access, or accidently present). These map limitations could be a potential source of bias (
To estimate the coverage of the Natura 2000 network in regard to the distribution of threatened species in Europe, we used an image processing protocol employing ADOBE PHOTOSHOP CS v8.0 (
In order to determine if country and Natura 2000 parameters could explain the coverage of threatened species by a national Natura 2000 network, we calculated the average coverage by country and compared it to seven socio-economic parameters of countries and three Natura 2000 indicators (Table 1; Appendix 1).
Details of all national indicators used with definition, abbreviations and units. Abbr. = abbreviation.
Class | Indicator | Abbr. | Definition | Unit | Ref. |
---|---|---|---|---|---|
Economic indicators | Gross domestic product | GDP | market value of all final goods and services made within the borders of a country/year | Million € | 1 |
Demographic indicators | Total population | TP | all persons residing in the country | Inhab. | 1 |
Population density | PD | number of individuals per surface units | Inhab./km² | 1 | |
National surface | NS | total surface of a country | km² | 1 | |
Urban population | UP | number of individuals residing in cities compared to the total population | % of total population | 1 | |
Ecological indicators | Ecological footprint | FP | amount of biologically productive land and sea area needed to regenerate the resources a human population consumes and to absorb and render harmless the corresponding waste | ha/person | 2 |
CO2 consumption | CO2 | weighted emissions of greenhouse gas emissions | Million tonnes of CO2 | 1 | |
Natura2000 indicators | Number of sites | NS | Number of Natura2000 sites | Number of sites | 3 |
Total area of sites | TA | Total area of all Natura2000 sites | km² | 3 | |
Natura2000 surface | %size | National network surface compared to total national surface | % of total surface | 3 |
References: 1:
For each species, coverage could range between 0 and 1, following a Poisson distribution. Therefore, we used a non-parametric Kruskal-Wallis ANOVA to test for differences between different species groups, member states and biogeographical regions. For refinement of the ANOVAs we employed the Tukey’s honestly significant difference (HSD) posthoc test to compare member states/biogeographical region where significant differences were found with the ANOVA. We also used a non-parametric ANOVA to test if the surface of biogeographical regions is correlated to the mean coverage, to the number of threatened species present within and to the proportion of Natura 2000 network per region.
We then determined an arbitrary threshold of 10% of coverage to detect threatened species for which the Natura 2000 network has a poor coverage. This threshold of 10% is assumed to be the minimum of coverage to assure an efficient protection to a given species (
We used linear models to analyse the extent country and Natura 2000 indicators (Table 1) explain the variation in coverage of threatened species by Natura 2000 (dependent variable ‘coverage’) per country (average of coverage ratios from all species living within the country) and the number of species with a coverage of less than 10% (dependent variable ‘Nspecies<10%’) using a Gaussian distribution and an identity link function. Because fishes were numerous in our database and poorly covered by the Natura 2000 network, we also conducted the same analysis only with these species to see if the national indicators could explain their specific coverage. Data were not available for Cyprus and Luxembourg, which were therefore excluded from this analysis. The best model among all possible sub-models was then selected using the corrected Akaike’s information criterion (AICc = 2 * [model performance log-likelihood + number of parameters estimated]): models explaining the most variation with the fewest predictors have the lowest AICc and were considered the ‘best models’. With a selection by AIC, one best model can be selected (if the difference of their respective AICc is < 2;
The global mean ratio of threatened species coverage was 0.359 ± 0.255 (mean + SD; median = 0.304). Depending on the taxonomic group, the global mean ratio varied from 0.292 ± 0.159 in insects (median = 0.261) to 0.452 ± 0.239 in reptiles (median = 0.412; see Fig. 1) but differences between taxonomic groups were statistically not significant (F8, 294= 0.936, P = 0.487). For only 6.6% (n = 20) of the analysed species, 90% of their distribution was covered by the Natura 2000 network. While 12% (n = 36) of the analysed species had only 10% of their distribution covered. The taxonomic group the least covered by Natura 2000 were fishes [22 (17.8%) threatened fish species]. Seven of these fish species are currently listed in the annexes of the Habitats Directive. In birds, only one species had a coverage of less than 10% in the Natura 2000 network. Overall, 42% (15 out of 36 species) of threatened species with a low coverage and 30% (6 out of 20 species) of threatened species with a high coverage by Natura 2000 were listed on the annexes I, II or V of the European Directives (see Appendix 1). However, comparing the coverage of threatened species listed by the European Natura Directives (0.339 ± 0.210) with the coverage of threatened species from the IUCN Red List (0.359 ± 0.255) did not reveal a significant difference (F1, 299= 2.512, P = 0.114).
The average Natura2000 coverage of threatened species by taxonomic group.
The mean coverage across biogeographical regions was 0.352 ± 0.244. We did not detect any difference in the coverage at the taxonomic group level (F8, 483 = 1.601, P = 0.122; Fig. 2a) in regard to the biogeographical regions, but found a significant difference at the species level (F8, 483 = 7.01, P < 0.001). Threatened species were best covered in the Black Sea (0.587 ± 0.300; median = 0.602), compared to the mean coverage of the Continenal (0.271 ± 0.203; median = 0.244), Atlantic (0.282 ± 0.269; median = 0.194), Boreal (0.191 ± 0.156; median = 0.146), Mediterranean (0.354 ± 0.254; median = 0.279) and Pannonian (0.287 ± 0.106; median = 0.270) regions (all Tukey’s HSD tests: P < 0.001). Threatened species were also well covered in the Alpine region (0.451 ± 0.210; median = 0.409), compared to the mean coverage of the Atlantic (Tukey’s HSD test: P = 0.004), Boreal (Tukey’s HSD test: P = 0.004) and Continental (Tukey’s HSD test: P < 0.001) regions. We found a poor coverage of threatened species in the Atlantic (17 out of 54 species = 31.5%), Boreal (26.7%) and Continental regions (14.7%; Fig. 2b and 2c).
a Difference between the Natura2000 coverage per species group and the mean coverage by biogeographical region (when positive, the coverage of the groups is better than the mean coverage of a region) b mean coverage by biogeographical region and c relative frequency of threatened species with a coverage below 10% by biogeographical regions. The number on top of the bars indicates the total number of threatened species studied per biogeographical region. The Pannonian region has no species falling in this category.
We did not find a size effect between the mean coverage and the surface of biogeographical regions (F1, 7 = 2.036, P = 0.197). We also did not find a relationship between the surface of biogeographical regions and the number of threatened species present within (F1, 7 = 2.41, P = 0.164), whereas we found a correlation between the surface of biogeographical regions and the proportion of the Natura 2000 network per region (F1, 7 = 6.06, P = 0.043).
The mean coverage across countries was 0.323 ± 0.225 (median = 0.282). Our comparison of the coverage of threatened species by a country’s Natura 2000 sites revealed significant differences at the taxonomic group level (F8, 583 = 2.929, P = 0.003). Insects appeared to be much less covered by the national Natura 2000 networks (0.242 ± 0.169) compared to reptiles (0.435 ± 0.229; Tukey’s HSD test: P = 0.034) and plants (0.388 ± 0.29; Tukey’s HSD test: P = 0.057).
Across species groups, the average coverage of threatened species by country showed significant differences (F24, 567 = 3.9596, P < 0.001). Notably, the United Kingdom (0.131 ± 0.218; median = 0.031) and Sweden (0.127 ± 0.113; median = 0.072) had a low coverage compared to the mean across countries, while Spain (0.407 ± 0.244; median = 0.333; Tukey’s HSD tests: P < 0.001) and Bulgaria (0.457 ± 0.218; median = 0.402; Tukey’s HSD tests: P < 0.001 and P = 0.014 respectively) generally showed a high coverage of threatened species. In the United Kingdom, 11 of 16 threatened species, all of them fish species and three listed on the annex II of the Habitats Directive, have less than 10% of their distribution covered by the Natura 2000 network (Fig. 3c). The Greek Natura 2000 sites cover 8 of 79 threatened species (1 amphibian, 7 fishes) with less than 10% (i.e. low coverage), while two of these species (2 fish species) are listed on the annex II of the Habitat Directive (Fig. 3c). In Spain only 5% of threatened species had a coverage of their distributions of less than 10% by the Natura 2000 network.
a Difference between ratio per species group and mean ratio by Member State (when positive, the coverage of the groups is better than the mean coverage of a country) b mean coverage of threatened species and c relative frequency of threatened species with a coverage below 10% by Member State. The number on top of each bar represents the total number of studied threatened species by Member State. The Natura 2000 network from non represented countries had no threatened species with a coverage of less than 10%.
The best model explaining the mean national coverage of threatened species (dependent variable ‘coverage’) consisted of the variable population density (PD) and the national network surface compared to total national surface (%size; F2, 22 = 13.12; P < 0.001; AICc = -46.7160; Table 2, Table 3 and Appendix 2). The variable %size had a higher explanatory power (t22 = 3.924; P < 0.001) than PD (t22 = -2.334; P = 0.029). Another model explaining the mean national coverage of threatened species included the percentage of national urban population (UP) and %size (F2, 22 = 11.75; P < 0.001; AICc = -45.2501; Table 2 and Table 3).
Results of the linear models showing the relationship between ratios of coverage and the extent national and Natura2000 indicators. Models with the dependent variable ‘coverage’ are models taken into account all threatened species. Models with the dependent variable ‘Nspecies10%’ are models taken into account only threatened species with a coverage <10%. All models with a ΔAICc < 2 are represented.
Variables | RSS | R² | AICc | ΔAICc |
---|---|---|---|---|
Coverage ~ %size + PD | 0.1514 | 0.5025 | -46.7160 | 0.000 |
Coverage ~ %size + UP | 0.1606 | 0.4725 | -45.2501 | 1.4659 |
Nspecies10% ~ CO2 + GDP + %size | 0.0012 | 0.7078 | -99.3453 | 0.000 |
Nspecies10% ~ CO2 + %size + TP | 0.0012 | 0.6869 | -98.1737 | 1.1716 |
Results of the best linear models selected by AICc values. (a) models with the independent variable ‘coverage’ and (b) models with the dependent variable ‘Nspecies10%’.
Variables | Estimates for variables | ||||
---|---|---|---|---|---|
(a) Models with the dependent variable ‘coverage’ | |||||
Model 1 | Estimate | DF | F | P | AdjR² |
Int. | 0.1465 ** | 2, 22 | 13.12 | < 0.001 | 0.5025 |
%size | 9.286x10-3 *** | ||||
PD | -1.627x10-4 * | ||||
Model 2 | Estimate | DF | F | P | AdjR² |
Int. | 0.3807 * | 2, 22 | 11.75 | < 0.001 | 0.4725 |
%size | 0.0075 * | ||||
UP | -0.0033 | ||||
(b) Models with the dependent variable ‘Nspecies10%’ | |||||
Variable | Estimate | DF | F | P | AdjR² |
Int. | 0.0335 *** | 3, 13 | 13.92 | < 0.001 | 0.7078 |
CO2 | -1.0381x10-4 ** | ||||
GDP | 1.73x10-8 * | ||||
%size | 1.381x10-3 ** | ||||
Variable | Estimate | DF | F | P | AdjR² |
Int. | 0.0371 *** | 3, 13 | 12.7 | < 0.001 | 0.6869 |
CO2 | -1.384x10-4 ** | ||||
TP | 1.017x10-9 * | ||||
%size | 9.679x10-4 * |
The best model explaining the mean national coverage of species with a low coverage (dependent variable ‘Nspecies<10%’) included the national network surface compared to total national surface (%size), the gross domestic product (GDP) and the weighted emissions of greenhouse gas emissions (CO2; F1, 13 = 13.92; P < 0.001; AICc = -99.3453). The mean national coverage of species with a low coverage was negatively correlated to CO2 (t13 = -3.901; P = 0.002) and positively correlated to %size (t13 = 3.268; P = 0.006) and GDP (t13 = 2.452; P = 0.029). Another good model explaining the mean national coverage of species with a low coverage included TP (total population) instead of GDP (F3, 13 = 12.7; P < 0.001; AICc = -98.1737; Table 2 and Table 3).
With only fish species and after model selection, 6 different models were retained. Within these 6 models, the percent of total Natura 2000 surface (%size), the population density (PD) and the percent of urban population (UP) have a significant effect on the coverage. As the retained explicative predictors were the same than in the global model (with all species) demonstrating a similar analysis, we did not show this specific result.
Here, we analysed the coverage of 300 threatened IUCN red listed species by the European Natura 2000 network. Our analysis showed that a large proportion of threatened species of mammals, birds and reptiles showed a high coverage (≥ 90%) by the current Natura 2000 network. Hence, the Natura 2000 network also covers species not listed in the annexes of the Nature Directives. However, our results revealed that a large proportion of threatened species, some of them even listed on the annexes of the Habitats Directive and especially fishes are currently poorly covered (≤ 10%) by the Natura 2000 network. Factors explaining the coverage of threatened species included national network surface compared to total national surface (%size), national proportion of urban population (UP), national population density (PD), gross domestic product (GDP) and weighted emissions of greenhouse gas emissions (CO2).
Our analysis showed an especially low coverage of threatened fish species by the Natura 2000 network (especially in the United Kingdom). Of the 124 fish species considered, 22 species had a range coverage of less than 10% by the Natura 2000 network, despite the fact that seven are listed in the annexes (II, IV and/or V) of the Habitats Directive [in United Kingdom: Coregonus clupeoides (La Cepède 1803), Coregonus pennantii (Valenciennes 1848) and Coregonus stigmaticus (Regan 1908); in Austria: Coregonus danneri (Vogt 1908); in Greece: Barbus euboicus (Stephanidis 1950), Eudontomyzon hellenicus (Vladykov, Renaud, Kott & Economidis, 1982) and Acipenser naccarii (Bonaparte 1836); see Appendix 1]. Concerning amphibians, three species (Speleomantes flavus, Rana latastei, Pelophylax epeiroticus) are weakly covered by the Natura 2000 network, of which two are listed in annex II and annex IV of the Habitats Directive. Speleomantes flavus (Stefani 1969) is endemic to Sardinia (Italy). This species is also listed in Appendix II of the Bern Convention but no conservation program is known at the moment, despite a need for close monitoring of the population status of this species (
Our analysis also showed that the region with the best average coverage of threatened species was the Black Sea region, covering 58.7% of the distribution ranges of threatened species. Although we did not find a size effect between the mean coverage and the surface of biogeographical regions, we want to stress that the Black Sea region is the smallest European biogeographical region (9705 km²) and has only 21 threatened species (7% of all species analysed here), while the total area of all Natura 2000 sites in this region represent 71.8% of the terrestrial surface (negative relationship between the surface of biogeographical region and the proportion of Natura 2000 network per region; see
Globally, our analysis confirmed that the Natura 2000 network, despite the huge efforts of the EU Member States, may have shortcomings in protecting some of the threatened species, also suggested by earlier studies on national (Dimitrakopoulos et al. 2004,
In order to improve the management of Natura 2000 sites (with a high efficiency), a common and standardized management of the Natura 2000 network with a uniform framework among member states needs to be established. Natura 2000 sites should be under continuous observation and evaluation, to determine their importance for the conservation of biodiversity in a biogeographical region, either using site selection algorithms as implemented in the programs ZONATION (
This publication is a contribution from the project SCALES: Securing the Conservation of biodiversity across Administrative Levels and spatial, temporal, and Ecological Scales, funded under the European Union’s Framework Program 7 (grant 226852; www.scales-project.net;
Summary of all threatened species studied with their IUCN status and their global ratio of coverage (next to each taxonomic group: mean + SD). (doi: 10.3897/natureconservation.4.3626.app1). File format: MS Word Document (doc).
Explanation note: The species listed on the annex of the Habitats Directive or Birds Directive have across in the relevant columns. An asterisk (*) before the species names indicates that the species is a priority species.
Principal component analysis of socio-economic, national indicators and parameters describing the Natura2000 network (see also Table 1). (doi: 10.3897/natureconservation.4.3626.app2). File format: MS Word Document (doc).