England and Wales Court of Appeal (Civil Division) Decisions

IN THE COURT OF APPEAL (CIVIL DIVISION)
ON APPEAL FROM THE HIGH COURT OF JUSTICE
QUEEN'S BENCH DIVISION
ADMINISTRATIVE COURT
MR JUSTICE MITTING
CO/1202/2013

		Royal Courts of Justice Strand, London, WC2A 2LL
		18/03/2015

Lord Justice Sullivan:

Introduction

1. This is an appeal against the Order dated 21^st May 2014 of Mitting J dismissing the RSPB's claim for judicial review of the decision of the Secretary of State for the Environment, Food and Rural Affairs ("the Secretary of State") dated 29^th May 2013 to direct Natural England under section 28F (5) of the Wildlife and Countryside Act 1981 ("the 1981 Act") to give BAE Systems (Operations) Ltd ("BAES") consent for:

(1) the culling of 552 pairs of Lesser Black-Backed Gulls ("LBBG") and further operations to maintain the population at the reduced level following the cull, provided that the population so reduced is no lower than 3,348 pairs; and

(2) further measures to maintain the population of Herring Gulls ("HG") at the population level following an earlier cull.

For convenience, I will refer to (1) and (2) as "the cull".

Background

2. The background to the RSPB's Claim is helpfully summarised in paragraphs 1-4 of Mitting J's judgment [2014] EWHC 1645 (Admin):

"1. The River Ribble rises in Yorkshire and flows into the Irish Sea between Lytham St Annes and Southport. The River Alt rises in Huyton and flows into the Irish Sea at the edge of the Mersey Estuary. Part of the Ribble Estuary was identified as a National Nature Reserve in 1979 and notified as a Site of Special Scientific Interest under Section 28 of the Wildlife and Countryside Act 1981 in 1984. It was classified as special protection area under Council Directive 79/409/EEC in 1982. The Alt River Estuary was similarly classified in 1985. The two estuaries were jointly classified as a special protection area in February 1995. It was re-designated and its area extended on 28 November 2002. It now comprises 12,412.31 hectares. It is a habitat for a large number of different species of bird. Amongst them are two large gulls: the Lesser Black-backed Gull and the Herring Gull. This case concerns only those gulls and that part of the special protection area which lies within the Ribble Estuary. Both gulls breed there. A reasonable working estimate of the numbers of breeding pairs in the Ribble Estuary in recent years is 4,100 pairs of Lesser Black-backed Gull and, until the recent cull, 500 pairs of Herring Gull. They nest in an extensive area of sand mud flats and saltmarsh on the left, south, bank of the Ribble.

2. On the right bank of the Ribble, to the north and east of that area is the aerodrome and manufacturing and research facility operated by BAE Systems (Operations) Limited ("British Aerospace") at Warton. British Aerospace and its predecessors have occupied the site since 1947. It is their principal UK facility for developing, manufacturing and testing military aircraft. Bird strike is an unavoidable occurrence. Small birds do not cause significant damage to aircraft; but large birds – those weighing more than 1kg – can do. The principal risk is that of ingestion into an aircraft jet engine. In the case of a single-engined aircraft, such as a Hawk, ingestion can lead to sudden total loss of power, requiring the pilot to eject and the aircraft to crash. The risk has been measured statistically. At Warton the annual frequency of the risk of damage to an aircraft sufficient to cause loss of service for a period of weeks has been assessed at 1 in 12.5 years and of aircraft loss associated with pilot ejection at 1 in 808 years. There is a national standard for yet more catastrophic loss, causing pilot fatality. That is set by the Health and Safety Executive at 1 in 1 million years. At Warton the risk is assessed at 1 in 30,000 years. A significant proportion of the Lesser Black-backed and Herring Gulls weigh more than 1kg. British Aerospace contends, without opposition from any source, that the two gulls are the primary cause of the risks identified above.

3. In an attempt to mitigate that risk, British Aerospace has sought consent for the culling of 1,700 pairs of Lesser Black-backed Gull and 500 pairs of Herring Gull on the Ribble Estuary site and the taking of measures to keep the numbers at the level produced by the cull. To do so British Aerospace required the written consent of Natural England under Section 28E Wildlife and Countryside Act 1981 or, if consent was not given, a direction by the Secretary of State for the Environment Food and Rural Affairs to Natural England following an appeal under Section 28F. Natural England consented to the culling of 200 pairs of Lesser Black-backed Gull and 25 pairs of Herring Gull, but refused to consent to the balance of the cull. British Aerospace appealed to the Secretary of State against that refusal. The Secretary of State appointed Edward A. Simpson to conduct a public inquiry into British Aerospace's notification. By a report dated 21 February 2012, Mr. Simpson recommended to the Secretary of State that he should direct Natural England to give consent to the full cull and subsequent control mechanisms. By a decision notified by a letter dated 12 December 2012, the Secretary of State directed Natural England to give consent to the culling of 475 pairs of Herring Gull (i.e. the balance left after the cull of 25 pairs permitted by Natural England). In a separate letter of the same date, he indicated that he was minded to direct Natural England to consent to a cull of a further 552 pairs of Lesser Black-backed Gull, but to affirm Natural England's decision as to the remainder of the cull – 948 pairs. He invited representations from all interested parties. By a decision notified by a letter dated 29 May 2013, he directed Natural England to give consent for the culling of 552 pairs of Lesser Black-backed Gull and further operations to maintain the population at a reduced level, provided that it did not fall below 3,348 pairs. By the date of this letter, the cull of 500 pairs of Herring Gull had been completed. The Secretary of State also directed Natural England to consent to further operations to maintain the population levels of Herring Gull at the reduced level.

4. By this claim, the claimant, The Royal Society for the Protection of Birds, challenges both of the decisions of the Secretary of State. The grounds of challenge are manifold, but at their heart assert that the Secretary of State was not, as a matter of law, entitled to direct Natural England to give consent to the culling of 552 pairs of Lesser Black-backed Gull."

The Habitats Directive

3. It is common ground that when deciding whether to grant consent for the cull the Secretary of State had to comply with the obligations imposed by paragraphs 2-4 of Article 6 of the Habitats Directive. Those obligations are as follows:

"2. Member States shall take appropriate steps to avoid, in the special areas of conservation, the deterioration of natural habitats and the habitats of species as well as disturbance of the species for which the areas have been designated, in so far as such disturbance could be significant in relation to the objectives of this Directive.

3. Any plan or project not directly connected with or necessary to the management of the site but likely to have a significant effect thereon, either individually or in combination with other plans or projects, shall be subject to appropriate assessment of its implications for the site in view of the site's conservation objectives. In the light of the conclusions of the assessment of the implications for the site and subject to the provisions of paragraph 4, the competent national authorities shall agree to the plan or project only after having ascertained that it will not adversely affect the integrity of the site concerned and, if appropriate, after having obtained the opinion of the general public.

4. If, in spite of a negative assessment of the implications for the site and in the absence of alternative solutions, a plan or project must nevertheless be carried out for imperative reasons of overriding public interest, including those of a social or economic nature, the Member State shall take all compensatory measures necessary to ensure that the overall coherence of Natura 2000 is protected. It shall inform the Commission of the compensatory measures adopted."

The Issue

4. The Secretary of State concluded that the cull would not adversely affect the integrity of the SPA: see Article 6(3). The RSPB contends that this conclusion was unlawful because it was based upon a misinterpretation of the conservation objectives for the populations of LBBG and the breeding seabird assemblage (of which the HG and LBBG are part) at the SPA; that the application of those conservation objectives, properly construed, would have led to the conclusion that the cull would adversely affect the integrity of the SPA; so that consent for the cull could have been given only if the necessary compensatory measures were taken in accordance with Article 6(4). Although the Secretary of State had concluded that there was no alternative solution and that there were imperative reasons of overriding public interest for carrying out the cull, he was not satisfied that adequate compensatory measures had been identified.

Conservation objectives

5. In Sweetman v An Bord Pleanála (Case C-258/11) [2013] 3 CMLR 16, Advocate General Sharpston considered how the reference to the "integrity" of a site should be construed for the purpose of Article 6(3). Having considered the differing language versions of the Article, she said in paragraphs 54-56 of her Opinion:

"54. Notwithstanding those linguistic differences, it seems to me that the same point is in issue. It is the essential unity of the site that is relevant. To put it another way, the notion of "integrity" must be understood as referring to the continued wholeness and soundness of the constitutive characteristics of the site concerned.

55. The integrity that is to be preserved must be that "of the site". In the context of a natural habitat site, that means a site which has been designated having regard to the need to maintain the habitat in question at (or to restore it to) a favourable conservation status. That will be particularly important where, as in the present case, the site in question is a priority natural habitat.

56. It follows that the constitutive characteristics of the site that will be relevant are those in respect of which the site was designated and their associated conservation objectives. Thus, in determining whether the integrity of the site is affected the essential question the decision-maker must ask is "why was this particular site designated and what are its conservation objectives?" In the present case, the designation was made, at least in part, because of the presence of limestone pavement on the site – a natural resource in danger of disappearance that, once destroyed, cannot be replaced and which it is therefore essential to conserve. "

The Court endorsed this approach in paragraph 39 of its judgment:

"Consequently, it should be inferred that in order for the integrity of a site as a natural habitat not to be adversely affected for the purposes of the second sentence of art.6(3) of the Habitats Directive the site needs to be preserved at a favourable conservation status; this entails, as the A.G. has observed in points AG54-AG56 of her Opinion, the lasting preservation of the constitutive characteristics of the site concerned that are connected to the presence of a natural habitat type whose preservation was the objective justifying the designation of that site in the list of SCIs, in accordance with the directive."

6. The European Commission's publication, "Managing Natura 2000 Sites", gives guidance as to the interpretation of certain key concepts in Article 6 of the Habitats Directive. Paragraph 4.6.3 deals with the concept of the "integrity of the site". This part of the guidance is summarised as follows:

"The integrity of the site involves its ecological functions. The decision as to whether it is adversely affected should focus on and be limited to the site's conservation objectives."

7. In view of the CJEU's decision in Sweetman and the Commission's guidance there can be no doubt that the Secretary of State was correct when he said in paragraph 22 of the decision that the conservation objectives for the SPA were "fundamental" to his consideration of whether the cull sought by BAES may have: (i) a significant effect on the site, and (2) an adverse effect on the site.
8. The obligations contained in Article 6(2), (3) and (4) are transposed into our domestic law by The Conservation of Habitats and Species Regulations 2010 ("the Regulations"): see regulations 9 and 61. Regulation 35(2) provides that:

"(2) As soon as possible after a site becomes a European marine site, the appropriate nature conservation bodies must advise other relevant authorities as to –

(a) The conservation objectives for that site.

(b) …."

The SPA is a "European marine site": see regulations 3(1) and 8.

9. Having noted that a clear statement of the conservation objectives was lacking during the inquiry in 2011, the Secretary of State considered Natural England's conservation objectives dated June 2012 together with Natural England's conservation objectives dated August 2011 when reaching his decision (paragraph 29 of the decision). The conservation objectives dated June 2012 for the SPA are as follows:

"With regard to the individual species and/or assemblage of species for which the site has been classified ("the Qualifying Features" listed below);

Avoid the deterioration of the habitats of the qualifying features, and the significant disturbance of the qualifying features, ensuring the integrity of the site is maintained and the site makes a full contribution to achieving the aims of the Birds Directive.

Subject to natural change, to maintain or restore

the extent and distribution of the habitats of the qualifying features;

the structure and function of the habitats of the qualifying features;

the supporting processes on which the habitats of the qualifying features rely;

the populations of the qualifying features;

the distribution of the qualifying features within the site."

The Qualifying Features include both the LBBG and the Seabird assemblage, but no baseline figures are given.

10. So far as relevant, the conservation objectives dated August 2011 are as follows:

"The Conservation Objectives for this site are, subject to natural change, to maintain the following habitats and geological features in favourable condition (*), with particular reference to any dependent component special interest features (habitats, vegetation types, species, species assemblages etc) for which the land is designated (SSSI, SAC, SPA, Ramsar) as individually listed in Table 1….

(*) or restored to favourable condition if features are judged to be unfavourable.

Standards for favourable condition are defined with particular reference to the specific designated features listed in Table 1, and are based on a selected set of attributes for features which most economically define favourable condition as set out in Table 2 and Table 3."

The designated Special Interest Features listed in Table 1 include the LBBG and the breeding seabird assemblage. When dealing with Species Populations, Table 2 explains under the sub-heading "Species Features – Population Size Objectives" that the "Conservation Objective for species extent" is:

"To maintain the designated species for the Ribble Estuary in favourable condition, which is defined in part in relation to their population attributes. Favourable condition is defined at this site in terms of the following site-specific standards."

The first standard is "Extent-Dynamic population balance":

"On this site favourable condition requires the maintenance of the population of each designated species, assemblage. Maintenance implies restoration if evidence from condition assessment suggests a reduction in size of population, assemblage."

The "Site Specific Target range and Measures" for the Aggregation of breeding birds is:

"Site Specific Target range and Measures.

Maintain population within acceptable limits (in this context the population can be that of an individual species or the total population of an assemblage). Based on the known natural fluctuations of the population in the site maintain the population at or above the minimum for the site. Where the limits of natural fluctuations are not known, maintain the population subject to natural change within acceptable limits, above 75% of that at designation – loss of 25% or more unacceptable….

Individual species present in nationally/internationally important numbers at designation are:..

Lesser Black-backed Gull (Larus fuscus) – breeds colonially. Breeding bird population size 4,100 (Seabird 2000) mainly confined to Banks and Hesketh Marshes. The baseline figure of Lesser Black-backed Gulls was confirmed as 4,100 pairs in 2008.

? 20,000 breeding seabird assemblage: assemblage baseline figure is 32,624 individuals"

11. For the generic guidance on favourable condition, the 2011 conservation objectives cross-referred to the August 2004 version of the "Common Standards Monitoring Guidance for Birds" published by the Joint Nature Conservation Committee ("the Guidance"). Paragraph 2.1 of the Guidance explains the "Conservation Objectives":

"The conservation objectives for birds in designated sites are determined by the legislative background to the designations in place. They are effectively aimed at maintaining bird populations or the diversity of species within defined assemblages, both through the protection of habitats supporting them and management against the negative impacts of disturbance. The attribute tables in this guidance list targets that should be used to aid in monitoring whether conservation objectives are being met for each of the interest features on a site."

Paragraph 3.1.4 explains that the baseline values for all attributes related to a feature will form the basis for establishing the target values to be met at each assessment. The Guidance explains the "Targets" in more detail in paragraph 3.5, as follows:

"3.5.1 Targets for bird attributes have been set to allow for natural fluctuation, effectively acceptable change, or for margins of error in measurement, in part due to technological advances. Different attributes will have different targets depending upon their nature.

3.5.2 For example, the population size of a species will fluctuate naturally, and for some species relatively widely, from one season to the next. So that these normal fluctuations are not misinterpreted as real declines or increases in a population the targets for population size are set to take account of the way in which a population is likely to change naturally. The targets for bird population size are set according to two approaches: known natural fluctuation at the site level for a species, and a generic threshold system. Wherever possible, known natural fluctuation should be adopted as the means for target setting as it will provide a more appropriate level of sensitivity for rarer species.

Known natural fluctuation – to derive population size targets from known fluctuation a minimum of five counts, each from a different relevant season, is required - these do not need to be from consecutive seasons, but should be from within a period of no more than 7 years. Ideally the counts should be from the time of designation of the feature – when the feature was known to be in favourable condition. If data are not available from the time of designation the first suitable series of good quality data should be used, or the generic threshold approach should be adopted. The minimum population size recorded during the five counts can be taken as the target for maintaining the population – if the population at assessment (taken from either a single count or a mean of counts) falls below this size then it is in unfavourable condition. When data from five years are not available to set the target the generic threshold approach must be used. Care should be taken in using natural fluctuation, as there may be cases where the fluctuation seen in a population is the result of non-natural phenomena, for example the effects of human disturbance. In cases where there is some doubt as to whether observed fluctuation is natural then the generic threshold approach should be used.

The generic threshold approach is widely used to assess the conservation status of individual bird species at the national level and to guide the setting of conservation priorities. The adoption of this system at the site level is a robust way of defining a common and easily used standard. A simple threshold system works by comparing population sizes at different times and deriving the change (expressed as a proportion of the initial population). If this change represents an absolute loss of 25%, or more, of a breeding population or 50%, or more, of a non-breeding population then the feature will be in unfavourable condition. These changes are the generic targets (thresholds) in CSM for the simple generic threshold approach…"

The Secretary of State's decision

12. Having considered the 2011 and 2012 conservation objectives, the Secretary of State set out his interpretation of the conservation objectives for the SPA in paragraph 30 of the decision:

"Reading these two documents together, the Secretary of State considers that he should interpret the conservation objectives for the populations of Lesser Black-Backed Gull and the breeding seabird assemblage as being:

Subject to natural change, to maintain or restore the features to favourable condition. Having reference to the favourable condition table (Table 2) of the conservation objectives document of August 2011, this means, subject to natural change, within acceptable limits, to maintain or restore the population above 75% of that at designation. Loss of 25% or more is unacceptable."

13. In paragraph 40 of the decision the Secretary of State concluded that 4,100 was the appropriate baseline for the LBBG conservation objective. He therefore concluded in paragraph 42 that the conservation objective for the LBBG was:

"Subject to natural change, to maintain or restore the feature to favourable condition. Having reference to the favourable condition table (Table 2) of the conservation objectives document of August 2011, this means, subject to natural change within acceptable limits, to maintain or restore the population above 75% of that at designation (4,100 pairs). Loss of 25% or more is unacceptable."

14. The herring gull is not an interest feature of the SPA in its own right. The Secretary of State considered the herring gull as part of the total population of the assemblage: see paragraph 93 of the decision. The Secretary of State concluded that the baseline population figure for the breeding seabird assemblage was 25,123. Applying the same approach as that set out in paragraph 42 of the decision, he concluded in paragraph 46 that the conservation objective for the breeding seabird assemblage was:

"Subject to natural change, to maintain or restore the feature to favourable condition. Having reference to the favourable condition table (Table 2) of the conservation objectives document of August 2011, this means, subject to natural change within acceptable limits, to maintain or restore the population above 75% of that at designation (25,123). Loss of 25% or more is unacceptable."

15. The Secretary of State decided that there was a requirement to carry out an appropriate assessment of the implications of the cull proposed by BAES "and whether it will have an adverse effect on the integrity of the site in view of the site's conservation objectives" (paragraph 56 of the decision). In paragraph 65 of the decision the Secretary of State said:

"…[T]he Secretary of State considers that it is appropriate to have regard to the favourable condition tables set out in the 2011 conservation objective document in deciding what the conservation objectives are for Lesser Black Backed Gull and the breeding seabird assemblage, and whether a proposal would have an adverse effect on the integrity of a site. The Secretary of State considers that, if after implementation of the proposals an interest feature will remain in favourable condition (and will be achieving its conservation objectives), then the proposals will not give rise to a risk of an adverse effect on the integrity of a site. The Secretary of State considers this further at paragraphs 73-91 below."

16. This approach – that if after implementation of the cull "an interest feature will remain in a favourable condition [as set out in the favourable condition tables in the 2011 conservation objectives] (and will be achieving its conservation objectives) then the proposals will not give rise to a risk of an adverse effect on the site" - was then applied in the later paragraphs of the decision letter. Thus, the Secretary of State's reasons for concluding that he could not give consent for the full cull sought by BAES were as follows:

"74. As noted at paragraph 65 above, the Secretary of State considers that the favourable condition tables located within the conservation objectives documentation inform his decision on what the conservation objectives are and the appropriate assessment in this matter. The Secretary of State agrees with BAES in principle that a reduction of the population to a figure which is above 75% of the baseline (4,100 pairs) will not result in the feature being in unfavourable condition. The Inspector seems to have agreed with BAES on this issue (IR9.29), albeit the Inspector was considering whether the proposals were likely to have a significant effect on the site. In principle, the Secretary of State considers that, if after the implementation of BAES's proposals an interest feature will remain in favourable condition, then those proposals would not give rise to an adverse effect on the integrity of a site.

75. The Secretary of State notes that the current Full Notification, in combination with past consents, would reduce the population of Lesser Black-Backed Gull by 1,700 pairs. In relation to a population of circa 4,100 pairs before any culling took/takes place, this would reduce the population to around 2,400 pairs (4,100 minus 1,700), and is the level at which the further control measures sought in the Full Notification would aim to maintain the population. This equates to a reduction of the population of around 40% from the baseline; the conservation objective is that a 25% loss from the baseline of 4,100 is unacceptable. In view of the fact that reducing the Lesser Black-Backed Gull population to this level, and maintaining it at that level, risks placing it in unfavourable condition, and in consequence, risks an adverse effect on the integrity of the site in view of the site's conservation objectives, the Secretary of State cannot consent to the Full Notification in its entirety."

17. The Secretary of State went on to consider what level the population could be reduced to by culling, and subsequently maintained at, without causing an adverse effect on the integrity of the site in view of the site's conservation objectives (paragraph 76 decision). The Secretary of State answered that question in paragraphs 77-82 of the decision, as follows:

"77. Although the conservation objective contemplates that a population which is above 75% of the baseline will be in favourable condition, the Secretary of State notes that, as the Full Notification seeks measures to maintain the population at a reduced level for the length of the consent, he must look to the longer-term prognosis for the Lesser Black Backed Gull population.

78. The Secretary of State has considered Natural England's assertion that the figure of 25% was intended to allow for 'natural change'. The Secretary of State agrees with the Inspector that it is not possible, or at least there is no evidence presented that could be used, to differentiate year-to-year variation from those due to anthropogenic effects once the birds have left the estuary (IR 9.29). Nonetheless, the Secretary of State does not consider that external factors should be ignored and accepts that they might have the potential to compound the effect of the cull. The Secretary of State concludes that the closer the population is maintained to 75% of the baseline, the higher the risk of impact on the population due to external factors such as disease or extreme weather.

79. The Secretary of State has also considered the wider Lesser Black-Backed Gull population. The Secretary of State notes that the Inspector concluded that the Lesser Black-Backed Gull is amber-listed in the Birds of Conservation Concern because of its restricted distribution rather than because of any long-term decline (IR 9.30). However, the Secretary of State also notes that other evidence was presented in the RSPB's 25 January submission (paragraphs 10-11 of Annex 1) which suggests a number of important populations are declining nationally, at least in the short to medium term.

80. The Secretary of State considers that both risks - that of an impact on the site's Lesser Black-Backed Gull population because of external factors, and risk to the wider Lesser Black-Backed Gull population if this site's population were to fall into decline – must be mitigated before the Secretary of State can determine what level of culling and corresponding level of further control measures can be permitted without risking an adverse effect on the integrity of the site, in view of the site's conservation objectives.

81. The Secretary of State considers these risks can be mitigated by (i) identifying whether there is a population, consistent with the conservation objective to maintain the population at above 75% of the baseline, which the Lesser Black-Backed Gull has existed at and which therefore provides a "safety margin" against external risk, and (ii) ensuring effective monitoring and feedback.

82. In relation to (i), the Secretary of State notes that the Lesser Black-Backed Gull population has fluctuated between 3,348 pairs and 4,117 pairs since it was added as a feature in 2002…. The Secretary of State considers that this evidence points to 3,348 pairs as being a population level at which Lesser Black-Backed Gull has existed at and fluctuated from since designation, and, being above 75% of the baseline population, provides an adequate safety margin against external risk. This means that, against a population of circa 4,100 pairs before any culling took/takes place, and taking into account the March 2011 consent for 200 pairs of Lesser Black-Backed Gull, this means a cull of 552 pairs could be allowed with further control measures as necessary to maintain the population at the reduced level following those culls. That is, following such a cull and maintained at no lower than that level, the feature would remain in favourable condition and would be achieving its conservation objective…."

18. The Secretary of State's conclusion on this issue was as follows:

"85. In conclusion, the Secretary of State is satisfied that there is no reasonable scientific doubt that, in combination with the past consent a reduction to 3,348 pairs and further control measures to maintain it at this level, alongside the monitoring plan set out in the Full Notification, will not have an adverse effect on the integrity of the site in view of the conservation objective to maintain the Lesser Black-Backed Gull feature in favourable condition. That the feature will remain in favourable condition and therefore be meeting its conservation objectives following the immediate culling and the longer-term further control measures means that there will be no adverse effect on the integrity of the site in view of the conservation objective. The Secretary of State therefore concludes that a cull of 552 pairs of Lesser Black-Backed Gull, in combination with the past consent, and further control measures to maintain the population at the reduced level, will not have an adverse effect on the integrity of the site in view of the conservation objective for Lesser Black-Backed Gull."

In paragraph 90 of the decision the same approach was adopted in respect of the breeding seabird assemblage.

Discussion

19. The Secretary of State's interpretation of the conservation objectives for the LBBG and the breeding seabird assemblage in paragraph 30 of the decision was, as he himself recognised in paragraph 22 of the decision, fundamental to his consideration of whether the cull may have an adverse effect on the integrity of the site. The proposition that the words "subject to natural change, to maintain or restore the features to favourable condition" meant, by reference to the favourable condition table (Table 2) in the 2011 conservation objectives, "subject to natural change, within acceptable limits to maintain or restore the population above 75% of that at designation….." (emphasis added) was applied throughout the decision, and in particular in paragraphs 46, 65, 74, 75 and 85 (see paragraphs 14-18 above). The Secretary of State's assessment of whether there would be "an adverse effect on the integrity of the site in view of the site's objectives" was based upon his interpretation of those objectives.
20. Although Mr. Forsdick QC submitted that only the 2012 conservation objectives were relevant, and that the Secretary of State should not have had regard to the 2011 conservation objectives because they related to the designated features in the Ribble Estuary SSSI (and not the SPA), and had in any event been superseded by the 2012 conservation objectives, I am content to proceed upon the basis that the Secretary of State was entitled to have regard to both the 2011 and the 2012 conservation objectives, and to read them together for the purpose of ascertaining the conservation objectives for the populations of LBBG and the breeding seabird assemblage at the SPA. The 2012 objectives were "high level objectives". They did not contain any baseline figures. While those figures could have been obtained from the data sheets, they were included in the 2011 objectives. Natural England's view was that the 2012 objectives were:

"consistent with the approach taken to conservation objectives at the inquiry, that the individual bird populations and assemblages for which the site is classified be maintained."

(see paragraph 28 of the decision)

21. The 2011 and 2012 conservation objectives are not enactments, and should not be construed as such. However, it was common ground that they mean what they say, and do not mean what the Secretary of State, or for that matter, Natural England or the RSPB, might wish that they had said. The conservation objectives must be read in a common sense way, and in context. They are conservation objectives for an area that has been classified as being of European significance under the Wild Birds Directive.
22. Starting with the 2012 "high level" objectives. The objective "Subject to natural change, to maintain the populations of the qualifying features" (which include the LBBG and the seabird assemblage) must be considered in the context of the overarching objective which is to:

"Avoid the deterioration of the habitats of the qualifying features and the significant disturbance of the qualifying features, ensuring the integrity of the site is maintained and the site makes a full contribution to achieving the aims of the Birds Directive."

In that context, it is difficult to see how a deliberate reduction of the populations of two of the qualifying features to a level above 75% of that at designation could sensibly be said to be in accordance with an objective of maintaining those populations, subject to natural change.

23. Turning to the 2011 conservation objectives, a straightforward reading of the objective - "subject to natural change to maintain the following habitats and geological features in favourable condition… with particular reference to any dependent component species features" (which include the LBBG and the breading seabird assemblage) – would not permit a deliberate (non-natural) reduction of the population of one or more of the species or species assemblies to a level above 75% of that designation and its maintenance at that reduced level for a period of ten years.
24. The Secretary of State referred to the favourable condition table (Table 2) in the 2011 objectives as the justification for his interpretation of the conservation objectives: "to maintain or restore the population above 75% of that at designation. Loss of 25% or more is unacceptable." However, it is clear that the definition of "favourable condition" in Table 2 of the 2011 conservation objectives (above 75% of that at designation is acceptable, loss of 25% or more is unacceptable) allows for natural fluctuations of population in the SPA. If the natural fluctuations of the population in the site are known, then the objective is to maintain the population at or above the known minimum for the site. If "favourable condition" is defined by reference to the ability of a species to maintain its population within a naturally fluctuating range rather than by reference to a particular figure, then deliberately reducing the population to the bottom end of the range, and maintaining it at that level for a period of ten years, thus preventing it from fluctuating above the lowest end of the range, is not maintaining the population in a "favourable condition."
25. The fact that the "favourable condition" targets in Table 2 are set to take account of natural fluctuations, and not non-natural phenomena such as a cull, is emphasised by the following passage in paragraph 3.5.2 of the Guidance:

"When data from five years are not available to set the target the generic threshold approach must be used. Care should be taken in using natural fluctuation, as there may be cases where the fluctuation seen in a population is the result of non-natural phenomena, for example the effects of human disturbance. In cases where there is some doubt as to whether observed fluctuation is natural then the generic threshold approach should be used."

Both the Guidance and Table 2 make it clear that "known natural fluctuations of the population" are the preferred method of ascertaining whether a site is in a favourable condition. The generic threshold method (loss of 25% or more of the population at designation is unacceptable) should be used "where the limits of natural fluctuations are not known." Thus, the 25% generic threshold is simply a proxy for the lowest end of a known, naturally fluctuating range. Properly construed, the conservation objective in the 2011 conservation objectives is not to maintain the populations of the LBBG and the seabird assemblages above 75% of that at designation; rather it is to maintain the populations at designation; and allowing for natural fluctuation, a loss of 25% or more is unacceptable.

26. If the 2011 conservation objectives are interpreted in this way, as they were by Natural England in its letter dated 25^th January 2013 in response to the Secretary of State's "minded to" letter dated 12^th December 2012 (see paragraph 3 of Mitting J's judgment), then they are consistent with the "high level" 2012 conservation objectives. On the Secretary of State's interpretation of the 2011 objectives – as permitting a deliberate reduction of the populations of the LBBG and the breeding seabird assemblage to a figure above 75% of that at designation – they would be materially different from the 2012 conservation objectives which are concerned to avoid "significant disturbance of the qualifying features" and to ensure that the integrity of the site is maintained and that it makes a full contribution to achieving the aims of the Birds Directive by maintaining the populations of the qualifying features, subject to natural change.
27. Natural England explained in its letter dated 25^th January 2013 why the Secretary of State's approach in paragraph 30 of the decision to the conservation objectives (which was foreshadowed in the "minded to" letter) was mistaken:

"[R]eliance on the monitoring targets contained in the favourable condition tables to support such a conclusion is not an appropriate use of those targets and should not be relied upon in the way that they appear to be relied upon to support a conclusion of no adverse effect on integrity. The Common Standards Monitoring Guidance is clear that the ranges and targets provided for allow for fluctuations due to natural population cycles or for margins of error in monitoring techniques. They are not intended as headroom or thresholds allowing planned or deliberate deterioration in site condition or changes brought about by anthropogenic factors such as habitat loss, disturbance and culling. This concern applies to the application of this approach to the breeding lesser black-backed gull feature and to the breeding seabird assemblage feature. A consequence of this approach, which if accepted in principle could apply to any species and assemblage on any SPA, is that large scale culls or any other activity that reduces bird numbers could be allowed to reduce a population down to 75% of the monitoring baseline or indeed 50% in the case on non-breeding populations. Where the current populations are above the monitoring baseline, this would also allow a cull of potentially many more than 25% of the population current at the time of the cull."

28. The Secretary of State's response to this point is contained in paragraph 78 of the decision:

"78. The Secretary of State has considered Natural England's assertion that the figure of 25% was intended to allow for 'natural change'. The Secretary of State agrees with the Inspector that it is not possible, or at least there is no evidence presented that could be used, to differentiate year-to-year variation from those due to anthropogenic effects once the birds have left the estuary (IR 9.29). Nonetheless, the Secretary of State does not consider that external factors should be ignored and accepts that they might have the potential to compound the effect of the cull. The Secretary of State concludes that the closer the population is maintained to 75% of the baseline, the higher the risk of impact on the population due to external factors such as disease or extreme weather."

29. Natural England's assertion that the figure of 25% was intended to allow for natural change was correct for the reasons set out in paragraphs 23-25 above. The proposition that it is not possible to differentiate year-to-year variation due to natural factors from those due to anthropogenic factors once the birds have left the estuary is true as far as it goes: a "natural" fluctuation in the LBBG population in the SPA may well be due at least in part to anthropogenic factors outside the estuary, eg the opening or closing of a landfill facility. However, it does not follow that the figure of 25% is intended to allow for the introduction of anthropogenic measures within the SPA which are intended to reduce the population and maintain it at a reduced level for ten years. It is one thing to say that some "natural" fluctuations in bird populations in an SPA may be due to off-site anthropogenic factors, it is quite another to give consent to a project within the SPA that is designed to reduce the bird populations in the SPA.
30. Both Mr. Tromans QC and Mr. Howell Williams QC submitted that the Secretary of State's decision had not been based solely upon his interpretation of the conservation objectives in paragraph 30 of the decision. They submitted that the Secretary of State had carefully examined the matters referred to in paragraphs 77-82 of the decision (see paragraph 17 above) before reaching his conclusion as to what level of cull would not adversely affect the integrity of the site. It is true that the Secretary of State did consider these other matters, but he did so upon the erroneous premise that if, after implementation of the cull, the populations of the LBBG and the breeding seabird assemblage would remain in favourable condition as defined in Table 2 of the 2011 conservation objectives, then there would not in principle be an adverse effect on the integrity of the site: see paragraphs 65, 74, 75 and 77 of the decision.
31. For these reasons, the Secretary of State's decision to direct Natural England to give consent for the cull is fatally flawed: the Secretary of State misinterpreted the conservation objectives for the SPA, and wrongly used a generic threshold which allows for natural fluctuation in the bird populations in the SPA to justify deliberately reducing those populations to, and thereafter maintaining them at, a percentage (above 75%) of the population at designation, which in the absence of a known minimum figure is simply a proxy for the bottom end of their natural range.
32. Mitting J concluded that the claim was academic insofar as it related to the HG: see paragraph 45 of the judgment. I do not agree. Although the cull of 500 pairs of HG had taken place by the time of the Secretary of State's decision dated 29^th May 2013, the decision to direct Natural England to give consent to further measures (ie further culls) to maintain the population levels of HG at the reduced level was based upon the Secretary of State's erroneous interpretation of the conservation objectives for the breeding seabird assemblage (which includes the HG), and is unlawful for the reasons summarised in paragraph 31 above.
33. Mr. Forsdick submitted that there was a further flaw in the Secretary of State's approach to calculating the baseline figure for the seabird assemblage. The breeding seabird assemblage was classified as a feature of the SPA in 2002. Using the period from 1998 – 2002 on the basis that it was the five-year period immediately preceding and including notification Natural England put forward a baseline figure of 32,624. The Secretary of State did not accept this figure for the reasons set out in paragraph 45 of the decision: over that period there were "significant variations" in the seabird assemblage population; the main reason for that variation was the "wide fluctuations of the Black-Headed Gull"; the 1999 survey data suggested an "unusually high count and possibly unrepresentative for the breeding seabird assemblage population at classification." The Secretary of State recalculated the baseline figure at 25,123 using the years 2000-2004, which excluded the "unrepresentative Black-Headed Gull figure in 1999" (paragraph 46 of the decision).
34. If one looks at the data in Appendix 3 to the 2011 conservation objectives it is difficult to see why the Secretary of State considered that the 1999 figure of 14,300 for the Black-Headed Gull was unusually high: there were higher figures in 1988 (20,000) and 1989 (15,500), and a figure of 11,875 in 1996. Mitting J said in paragraph 44 of his judgment that there was an element of casuistry in the Secretary of State's approach, but he was not persuaded that the approach was irrational or unlawful. On this aspect of the challenge to the Secretary of State's decision I agree with Mitting J. Ascertaining the baseline figure for the assemblage was not simply a mathematical exercise, it required the Secretary of State to exercise his planning judgment as to which counts would give the most representative figure. The Secretary of State has given reasons for excluding the 1999 figure for the Black-Headed Gull. Those reasons are intelligible. If this was an appeal on the merits I would have said that they are unconvincing, but I am unable to conclude that they are irrational.

The statutory scheme

35. In paragraphs 6-36 of his judgment Mitting J analysed the statutory scheme before he considered the Secretary of State's reasoning in the decision letter dated 29^th May 2013. In my judgment, an analysis of the statutory scheme is not necessary for the purpose of deciding whether the Secretary of State misinterpreted the conservation objectives for the SPA. Before this Court there was little, if any, dispute between the parties as to the statutory scheme. Mitting J's analysis differs in a number of important respects from the analysis which was, in effect, a matter of common ground between the parties, both in this Court and, we were told, before Mitting J. At our invitation the parties focussed their oral submissions on the reasoning in the Secretary of State's decision. For my part, I would not have analysed the statutory scheme in the same way as Mitting J, but since we did not hear oral submissions on that issue, it would not be sensible to embark upon a detailed consideration of the RSPB's criticisms of Mitting J's analysis. If we are agreed that the reasoning in the Secretary of State's decision was flawed for the reasons set out above, any views that we might express about the statutory scheme would be obiter.

Conclusion

36. I would allow the RSPB's appeal, and quash the Secretary of State's decision dated 29^th May 2013.

Lord Justice Sales:

37. I agree.

Lord Justice Jackson:

38. I also agree.