Natura 2000 and conservation status of habitats and species

Transcription

1 Natura 2000 and conservation status of habitats and species The members of the Expert Group on Reporting under the Nature Directives are invited to provide written comments to this paper by 19 April This version March 2013 takes into account discussions and proposals made by an ad hoc group of experts from a few Member states, the ETC/BD and the that met on 4 and 5 March 2013 in Copenhagen. It also includes written comments provided by several experts from the ad hoc group after that meeting. The purpose of this paper is to present possible analyses and assessments that may contribute to answer the following question from Article 17.2 of the Habitats Directive: what is the contribution of the Natura 2000 network to achieving favourable conservation status. Additional information on the background to this work is given in the Appendix. The paper includes proposals on how to - Explore practical and relevant ways of using the information that will flow from the coming articles 12 and 17 reports - Present outcomes to support of the preparation of an technical report on articles 12 and 17 reports. The paper is divided in three parts: - The first, lists several questions that contribute to elucidate the main issue of the contribution of the network to the conservation status - The second, presents a series of explanatory data analysis summarising the main outcomes from the reporting that are relevant to address the questions in part one, and provide background to the detailed analysis - The third, includes some detailed analysis largely based on statistical methods, but also covering other investigations While discussing this topic and the analysis proposed, several issues were raised by the different experts. Instead of mention them along the different analysis we opted by listing them below to allow a better context for what is being proposed and facilitated further discussions. 1

2 General issues to consider (Note: these are mostly quotes from experts; we will re-write and arrange them on a later stage) - There are differences between the two reporting periods because of differences in methods and (monitoring) data; it is expected that changes observed for a given species/habitat will be a mix of genuine change and change in methods. YES, but either we accept and highlight that fact (caveats) when presenting results, or we will only be able to make a very few comparisons - Changes between the two reporting periods include changes in the geographical scope of the reporting (EU25 vs. EU27) and changes in the annexes of the directives (linked to the point above) - Restoration takes time, so it takes time to see results: a validation of necessary measures and time scales for possible restoration of a favourable conservation status should be made, and an analysis could separate out groups of restoration time needed in relation to the expectation (that CS will be better within Natura 2000, or better for species/habitats with a high proportion in the network. YES, but this is potentially a huge task that would require a carefully planning based on the outcome of the work over the next couple of years rather than something that can be done as part of the work envisaged in this paper. Can the new biogeographical seminars play a role were? - There may be other protection regimes at work in the Member State (or in countries outside EU27), so we cannot tell for certain a difference is only caused by Natura Species with high proportion inside the network can be very rare and vulnerable and may be already beyond help (to achieve FV) (and will downgrade the results), the other way around species mainly outside may have been doing better all along - Because of the difference in ecology and/or distribution (middle or edge of range) between member states, the analyses can only be done by (biogeographical region by) MS and not on a larger scale - Sometimes we want a species or habitat to do better outside the network (e.g. the network is "full" already), resulting maybe in a better trend outside than inside - see the imperial eagle example 2

3 1. Questions building an analysis framework In order to assess the contribution of Natura 2000 for the conservation of targeted species, it is possible to use the approach by Donald et al. (2007) 1 in their study on the contribution of the Birds Directive for conservation of bird species: The questions below are inspired on the four main questions used in the paper mentioned above. - Are populations of Annex II species better represented in Natura 2000 increasing more than those less represented? This question could be investigated by groups of species: e.g. forest species, freshwater species - Is there an increase of Annex II populations in EU27 compared to non-eu27? Probably the best approach is to look at a few case studies comparing for instance: Sweden/Norway, Austria/Switzerland, Bulgaria/Serbia; use of Red Lists EU vs. pan-europe could also be investigated - Are positive trends more obvious in species that have been listed in Annex II longest? To simplify, we could investigate trends of species listed in Annex II before and after Do Member states with larger coverage of SCIs have better area / population trends? - Do species and habitats with a large proportion of their population or area within Natura 2000 have a better conservation status favourable, or unfavourable but improving than those with more of their population or area outside the network? And why? Note: Annex IV (and V) species may have to be analysed separately since their protection region is different from Annex II species. Another fact has to be taken into account: the restoration possibilities and time-scales are very different for the species and different habitats. Thus habitat types or species with restoration times of more than years or even longer are not likely to be better of within Natura 2000 in this reporting period. Therefore for some species/ habitats the hypothesis could be made up, that highly threatened rare species with difficult restoration, likely to be better represented in N2000, will not show differences within short to medium time. 1 Donald, P.F., Sanderson, F.J., Burfield, I.J., Bierman, S.M., Gregory, R.D., Waliczky, Z International Conservation Policy Delivers Benefits for Birds in Europe. Science 317:

4 2. Explanatory data analysis Note: unless otherwise stated and for the purpose of this document, 'biogeographic level' means the biogeographic region at the Member State level, which is the finest resolution of most of the data reported under article 17. Both the Birds and the Habitats reports will deliver data on two aspects (sections 8 and 3 respectively): - Population size (for species) and surface area (for habitats) inside the network - Main conservation measures implemented and their broad evaluation MS are also requested to report on trends, although for trends within the network the information is non-obligatory and, therefore, likely to be missing for most features. The above information is limited to Annex I habitat types, Annex II species, and Annex I and (key) migratory bird species. In addition, MS will provide estimations of population size at the national level for birds (section 2) and at the biogeographical level for other species (section 2.4); estimation of the habitat types surface area at the biogeographical level are reported in section 2.4. Using data from the MS evaluations allows a more direct link between the network (Nature 2000), the measures taken, and the conservation status at a 'finer' scale the MS biogeographic region compared to the EU biogeographical region. However, we may have to take into account possible differences between MS in the reported data by, for example, using reliable complementary data sources. We present below a series of possible analysis using the data described above. These analysis aim at 'setting the scene' by providing factual information that can frame and help developing further analysis. Analysis 1 - Coverage by the network It should be possible with the information provided to estimate the proportion of the population of each species and of the surface area of each habitat type that is covered by the network. For features of the Habitats Directive (species and habitat types) both the proportion for each biogeographic region of the MS and at national level can be estimated: P sp = (N in SCIs/SACs) / (N at biogeographical or national level) P hab (A in SCIs/SACs) / (A at biogeographical or national level) Where P is proportion, N is population and A is area For birds it will be only possible to estimate the proportion at the national level: P bsp = (N in SPAs) / (N at national level) From the above individual proportions it would be possible to calculate frequencies and construct frequency distribution tables using any given intervals to group proportions. 4

5 A major issue to look into will be the spans between minimum and maximum value, and for species also the estimation /conversion of population units. Probably we have to use Min-max values in the graphics and not averages. Note: the actual classes to be used in future analysis can only be established once we have collected the data from the reports and analysed it; we will then see which kind of distribution the data follows normal, right or left skewed (see illustration above) For example (assuming a normal distribution), Proportion of the feature included in the network < 20 less than 20 % from 20 to 40 % from 40 to 60 % from 60 to 80 % % or more In addition, we could highlight features fully included in the network (100 %), corresponding to localised and/or endemics or with a very low representation (e.g. less than 10 %, if any). Other possible splits are: < 20 % > 80 % or < 10 % > 90 % Frequency distribution table, figures given as percentages (dummy data) Interval Annex I Habitats Annex II Species Birds < And the above table could be complemented with a comment like: including 12% of birds, 5% of habitats, 15 % of other species fully covered (100 %) by the network (dummy data). 5

6 The graph in Figure 1 illustrates one possible way of presenting overall results, for example - The majority of habitat types (55 %) have at least 75 per cent of their surface area in the network - 35 % of the bird species (Annex I and migratory from the Birds Directive) have between 50 and 75 per cent of their population within the SPA network Figure 1 Overall coverage by the network (percentage of features in each of the four classes) dummy data Habitats Species Birds < Note: the classes used are different from the ones in the text given the lack of time to update the graph. Frequency distribution tables like the one below (dummy data) could be used to present the results for any given set of features e.g. mammals, vascular plants, forest habitat types, etc. Interval ALP ATL BLS BOR CON MAC MED PAN STE < This kind of statistics could be useful to analyse possible differences between biogeographical regions, between MS in a given biogeographical region, between groups of habitats, or any other combination of features. For example, the data presented in the table above for biogeographical regions could be made for the different habitat categories marine, coastal, grasslands, etc. 6

7 Figure 2 below illustrates one possible way to present the data from the table in an easy to read format. Figure 2 Coverage by the network by biogeographical region for 'feature Y' 100% 90% 80% 70% 60% 50% 40% 30% dummy data < 25 20% 10% 0% ALP ATL BLS BOR CON MAC MED PAN STE Note: the classes used are different from the ones in the text given the lack of time to update the graph. 'Feature Y' may be a single habitat or species, a group of species or habitats, all habitats or all species. Note: the type of graph staked, single bars, etc. will be chosen to provide the best readability possible. Examples of conclusions from the above graph - Coverage of 'feature Y' in the network of the Pannonian region is low compared to other regions - 10 % of the habitat types in the Alpine region have less than 50 % of their surface area covered by the network - 50 % of the species in Macaronesia have more than 75 % of their occurrences within Natura 2000 The general analysis above could be refined with particular cases. One of those could be: 'Do localised habitats/species (i.e. with a restricted area of distribution) tend to have a higher proportion of the resource in the Natura 2000 network?' 7

8 Localised habitats and species It is quite probable that habitats or species with a limited area of distribution will be better covered by the networks. To understand the patterns in the coverage by Natura 2000 it will be necessary to analyse the differences between regions and habitat/species groups, the relationship between the coverage and the habitat/species size of the distribution area. These analyses can help as to identify the localised habitat and species. The restrictedness of a habitat can be expressed as total area of habitat in the biogeographical region (or percentage of the area of biogeographical region covered by a habitat). For a species the restrictedness can be estimated based on the area of habitat occupied by the species; ideally, we should use the population size, but this may not be possible since different countries may use different population units. Figure 3 Habitats - relationship between the area of distribution and percentage of its overlay with Natura The area of the distribution was log transformed as the relationship is not linear but logarithmic (based on data from the previous reporting period). percentage y = -6,8461Ln(x) + 131,9 R 2 = 0,3758 log distribution area Note: the above analysis could be complemented by attributing the conservation status to each of the above points (i.e. as red = U2, amber = U1, green = FV, and grey = XX), and see if there is any kind of relation between area of distribution, coverage by the network, and conservation status. 8

9 Habitat specialisation (Annex II species) Building upon the expertise that has already been developed in the framework of Natura 2000 seminars on attributing species to ecosystems and to habitats of Annex I it is possible to classify Annex II species as generalists or specialists. For example, a species which indistinctively use several types of ecosystem during different stages of their life can be considered as generalist provided it is not restricted to a particular habitat for a particular lifecycle stage. A species with a relatively narrow ecological niche and that can only live in a particular habitat type or needs a particular habitat type for part of its life cycle can be considered as habitat specialist. We could investigate if there are differences in the coverage by Natura 2000 between generalist and specialist species. Using the results from analysis 1 The objective of the above analysis is to judge whether the Natura 2000 network is a particularly important instrument for the conservation of a habitat/species. Knowledge of the conservation status of the species and habitat inside and outside N2000 would greatly facilitate the analysis of the network contribution to conservation status; however, it is not yet possible to have this information. Another aspect to bear in mind is that other protection regimes as effective as N2000 may exist outside the network and then the interpretation / outcomes will differ. The parameters estimated in these analyses (coverage by the Natura 2000, the fact whether a habitat/species is localised, habitat specialisation) can be combined into an index of site importance in the similar way as the Site Provision Index for birds developed the UK SPA and Ramsar Scientific Working Group (Williams, G. et al in preparation) However, the coverage by Natura 2000 will be probably the most important parameter to estimate the importance of Natura 2000 for a habitat/species. 9

10 Analysis 2 Trends The reporting from both Article 17 and Article 12 includes different types of trends: - Trend in overall assessment of conservation status (e.g. U1 to FV, U1 to U2, U1 to U2); additionally, MS are required to indicate for the Unfavourable assessments their overall trend using qualifiers : + (improving), - (deteriorating), = (stable), or x (unknown) (e.g. U2 to U1+, U1 to U1-) - Trends assigned to a parameter assessment (e.g. population assessment from U1 to FV, structure and functions from U1 to U2) - Trend within certain parameters For habitats: range trend, habitat area trend (habitat area trend is however quite conservative, the restoration efforts will not lead immediately to increase in habitat area) For species: range trend, population trend, habitat of species trend (this should cover both quantitative and qualitative aspects). Contrary to trends reported for habitats, population trend and habitat area & quality trend (particularly relevant for specialist species) tend to respond relatively quicker to conservation measures. For birds, range trend and population trend, both long-term and short-term For habitats, Annex II species and birds trends within the Natura 2000 will not possibly be available for all features, so it will not be possible to exploit this information systematically. Trend information within parameters is obligatory at the biogeographical/national level, but optional within the network. In theory, it would be possible to compare trends for groups of species or habitat types with different coverage by the network using both national and network trends. The overall conservation status of a habitat or species is a function of several parameters; for quantitative parameters, such as habitat area and population, the conservation status is a combination of trends and proximity of actual and reference values. Trends tend to be more sensitive to changes in comparison to the overall conservation status, as they are not dependant on static reference values. Trend information can be used in a similar way as conservation status (as an alternative response variable) in statistical analysis and in various graphical comparisons. For example, we can compare trends across the coverage categories, or we can compare particular trends between the class where Natura 2000 is not a major conservation instrument (e.g. coverage < 20 %) with the class where Natura 2000 has a major role (e.g. coverage > 80%). 10

11 Figure 4 - Trends in classes with different coverage by Natura 2000 network % 50-75% dummy data 0-50% 0% 20% 40% 60% 80% 100% + = x - Or we can compare improvements/ deterioration of trends in the classes with different coverage. Change in trends between reporting periods Trends in No change Trends in = XX Deteriorated Deteriorated # = Improved No change Deteriorated # Improved Improved No change # XX Probably improved # Probably deteriorated No change # changes difficult to interpreter, probably need to study case by case Note: the information on trends from the reports is very seldom; therefore, this kind of analysis may not be relevant for the near future Or we can simply compare the number of features in each trend category between two reporting periods. See example below showing changes in the status of the UK BAP priority species, 1999 to 2008 from the UK Biodiversity Indicators. These graphs use data from the 1999, 2002 and 2008 UK Biodiversity Action Plan reporting rounds. Reports were not provided for each species for each year, so the indicator uses comparisons between 199 and 2008 if they are available, but also includes comparisons between 1999 and 2002, and between 2002 and 2008 if these are the only data available hence the columns being labelled earliest and latest available assessments. 11

12 Figure 5 - changes in the status of the UK BAP priority species, 1999 to 2008 Source: 12

13 Analysis 3 - Conservation measures and their results Information on conservation measures for Annex I habitat types, Annex II species, Annex I plus migratory bird species includes: - Measures from a common checklist - Type of measures - Ranking, top 5 identified - Location inside/outside the network - Broad evaluation of the measure is it working? The above information can be summarised and organised using the same groupings as for the statistics on the coverage of the network; this information will be used to interpret trends from 'analysis 2' and changes in conservation status. Which pressures are addressed by conservation measures? We can analyse the extent to which degree reported pressures are addressed by conservation measures and whether these measures are implemented mainly inside or outside the Natura 2000 network. For example, we could express quantitatively the proportion of high ranking pressures addressed by conservation measure(s) and estimate whether these measures are implemented mainly inside, both inside and outside or mainly outside the Natura 2000 sites (see a possible template-table below). Pressures with high ranking Pressure 1 Pressure 2 Pressure 3 Pressure 4 Addressed by conservation measures To large extent (measure(s) with H ranking) Partly (measure(s) with M ranking) Partly (measure(s) with M ranking No Measure(s) applied mainly inside N2000 Both inside and outside N2000 This table could be filled for different ecosystems or groups of habitats and species particularly linked to them: agriculture, forests, freshwater, Mainly outside N2000 The problem of this analysis is that for both pressures and measures we will have only very indirect indications of their relative importance in relationship to the proportion of habitat area/species population affected. For pressures, the pressures with high ranking should have important direct or immediate influence and/or act over large areas. For measures, five measures with relatively highest importance (in comparison to other measures) in terms of area/population affected have high ranking. So actually it is not possible to judge whether existing pressures are addressed on sufficiently large areas by implemented measures. However, this analysis can provide an insight into whether the Natura 2000 network facilitates the implementation of measures relevant to most important pressures. The link between implemented conservation measures and high ranked pressure can help us to focus on most relevant conservation measures. This analysis would require making a table of correspondence between pressures and conservation measures. 13

14 Figure 6 - Frequencies of measures implemented inside, both inside and outside the Natura 2000 sites in different categories of measures. Measures related to: special resource use urban areas, industry, energy and transport dummy data hunting, taking and fishing.. spatial planning marine habitats w etland, freshw ater and coastal habitats forests and w ooded habitats agriculture and open habitats No measures Frequency of reported measures inside N2000 inside&outside N2000 outside N2000 NA Broad evaluation of the reported measures The reporting format further requires countries to make a broad evaluation of the measures in terms of their effectiveness in maintaining, enhancing or reaching favourable conservation status. Statistics describing the patterns in the reported measures can be based on frequency of reported measures i.e. showing how many times a particular type of measure with a particular evaluation was reported. Figure 7 - Frequencies of reported measures with high ranking having different impact on conservation status implemented inside, outside or both inside and outside the Natura 2000 sites. unknow n (61) dummy data no effect (171) longterm (79) enhance (98) maintain (84) inside N2000 inside&outside N2000 outside N2000 NA 14

15 Analysis 4 - Conservation Status Conservation status of habitat types and species covered by the annexes of the Habitats Directive at the EU biogeographical level will be assessed by the -ETC/BD on the basis of the MS data. Figure 8 gives the overall results for habitat types from the 2007 reports: percentage of assessments in each category of conservation status. Figure 9 gives the same information for Annex II species. Figure 8 Conservation status of Annex I habitats ( ) at the EU biogeographical level Figure 9 Conservation status of Annex II species ( ) at the EU biogeographical level The same type of statistics should be produced with the assessments made by the Member States. The conservation status assessments can be summarised and presented using the same groupings as in the previous analysis, which may facilitate the integration of results. For example, using classes of coverage by the network. Figure 10 - Percentage of assessments in classes of coverage by the Natura 2000 network (dummy data) 0-50% 50-75% % dummy data 0% 20% 40% 60% 80% 100% U2 U1 XX FV 15

16 Changes of conservation status It is possible to present changes between the conservation status reported in 2007 and Change in conservation status between reporting periods CS in CS in FV U1 + U1 U1 - U2 + U2 U2 - XX FV Stable Det Det. Det Det Det Det Unkn U1 Imp Imp Stable Det Det Det Det Unkn U2 Imp Imp Imp Imp Imp Stable Det Unkn XX Imp Imp Det Det Imp Det Det Unkn Det = deteriorating Imp = Improving Unkn = Unknown Note: there is almost no information on 'qualifiers' (+ or -) in the 2007 reports, but we expect this information to be more widely reported by MS in 2013 Different combinations of the above changes can be depicted in graphics by, for example, classes of coverage by the network (see below a couple of examples). Figure 11 Overall conservation status for the reporting (right) and changes (trends) in the overall conservation status between two reporting periods (left) dummy data 16

17 Figure 12 below illustrates a possible way of representing changes in the overall conservation status; for example, from the total number of favourable assessments in 2013, 70 % were also favourable in 2007 (stable), 10 % were unfavourable inadequate (improvement), and 20 % were unknown (better knowledge). Figure 12 Origin of the changes in the overall conservation status dummy data For both figures 11 and 12 it would be possible to also show the conservation status qualifiers (improving, deteriorating), and also possible to produce by country and produce as maps with graphs overlaid. 17

18 Detailed analysis We present below a few proposals for discussion. The objective is to find which of them are more relevant to address the issue, their feasibility, caveats, etc. Correlation between coverage by Natura 2000 and Conservation Status For a given biogeographic region Annex I % coverage by N2000 Conservation status 2007 and Conservation status 2013 Habitat h1 55 U1 FV Habitat h2 88 U1 U1 Habitat h3 77 FV FV Annex II % coverage by N2000 Conservation status 2007 Conservation status 2013 Species s1 66 U2 U1 Species s2 100 U1 U2 Species s3 75 FV FV It would be possible to use a statistical method to investigate the correlation between 'percentage of coverage by N2000' and 'conservation status. What kind of statistical method(s) is(are) the most appropriate? What would be the constraints? This will be further investigated, namely by consulting statisticians and using real data when it becomes available. The correlation could also be investigated using different groupings of habitats and species as mentioned in the previous sections. And could we also investigate relation/correlation between coverage and changes in CS between two periods? Notes: - higher % of coverage and unfavourable status could be 'justified' by: the feature is in a bad situation, so we need more inside Natura 2000, and the conservation measure have not yet started to work, or - features with higher % of coverage have better CS status than those with low coverage because measures are concentrated in the network One particular aspect to take into account when correlating coverage by the network and conservation status (or trends) is the case of species that at a given moment were largely or only present in the network, but due to successful conservation measures expanded their populations to other areas not included in the network: in those cases one would observe a lower (even much lower) coverage by the network after conservation action was taken. There 18

19 are several examples with birds, including for example the Imperial eagle (Aquila adalberti) in the Iberian Peninsula (see below). Evolution of the number of breeding pairs of the Spanish Imperial Eagle (Aquila adalberti) in the province of Segovia (Castilla y León, Spain). Number of breeding pairs Year Inside SPA Outside SPA % in SPA Start of action plans Note: Table built from unpublished data owned by the Junta de Castilla y León. 19

20 Practical example The following example was prepared by James Williams (JNCC, UK). The hypothesis to be tested is the following: - More species and habitats with a large proportion of their population or area within protected sites will be at a favourable, or unfavourable but improving, conservation status than those with more of their population or area outside the site network Three stages are described below to answer the above question. First stage: 20

21 Second stage: 21

22 Third stage: 22

23 All three stages are shown together below: 23

24 Appendix Background According to Article 17.2 (Habitats Directive): The Commission shall prepare a composite report based on the reports referred to in paragraph 1. This report shall include an appropriate evaluation of the progress achieved and, in particular, of the contribution of Natura 2000 to the achievement of the objectives set out in Article 3.( ) Therefore, Article 17.2 calls for an appropriate evaluation of the contribution of Natura 2000 (set as a coherent ecological network) to enable habitats and species to be maintained/restored at favourable conservation status (FCS) in their natural range. The work to support that requirement started in 2009 under the former 'work package 3 WP3' aimed at developing 'methods for the evaluation of the contribution of the Natura 2000 network to the maintenance or restoration of a favourable conservation status of species and habitats'. Later on, the scope of the work was enlarged to also cover birds, thus allowing more comprehensive assessments. The WP3 group identified sets of data parameters deemed necessary (although not sufficient) to evaluate the contribution of the network to the conservation status of habitats and species; these were: - Relevance of the network for the different species and habitats: proportion within the network - Possible differences in trends within the network compared to the general trend - Understanding what type of conservation/management measures the countries have implemented As a practical consequence of the above, the group focused its work in developing new sections for the reporting formats of Article 12 (Birds Directive) and Article 17 (Habitats Directive), respectively: - Section 8 SPA coverage and conservation measures (national level) - Section 3 SCI/SAC coverage and conservation measures (biogeographic level) A draft of this paper was presented at the last meeting of the Expert Group on Reporting under the Nature Directives (22 November 2012) 24