Assessing ornithological impacts associated with wind farm developments: surveying recommendations

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1 Assessing ornithological impacts associated with wind farm developments: surveying recommendations This information note has been written to provide guidance to developers, Competent Authorities and others in assessing wind farm developments that may affect the Humber Estuary Special Protection Area (SPA) and Ramsar site, Thorne and Hatfield Moors SPA, Lower Derwent Valley SPA and Ramsar site and Hornsea Mere SPA. This note provides technical advice regarding the necessary procedures under the Conservation (Natural Habitats, &c.) Regulations 1994 (the Habitats Regulations). It should be read in conjunction with other guidance notes including the Habitat Regulations Guidance Notes, the Scottish Natural Heritage guidance Survey methods to assess the impacts of proposed onshore wind farm on bird communities and all the relevant citations and conservation objectives for the above sites and other relevant literature. It is important to note that this guidance constitutes without prejudice advice only. It is not possible to be absolutely prescriptive in terms of precise methodologies as these will need to be developed on a case by case basis. Note, the component SSSIs of the above SPA and Ramsar sites are also afforded protection under the Wildlife and Countryside Act (1981) as amended. This note does not consider nonornithological features of national or international importance. The aims of this note To provide summary guidance on identifying potential impacts of windfarm development on the SPA/Ramsar species cited within the Humber Estuary, Thorne and Hatfield, Lower Derwent Valley and Hornsea Mere Special Protection Areas. To recommend necessary survey methodologies and appropriate survey effort. To improve consistency when advising developers, local planning authorities, Competent Authorities and others. To support Competent Authorities in discharging their duties under the Habitat Regulations. Potential impacts The potential impacts of wind farms on bird populations are: Direct loss/deterioration of habitat. Indirect habitat loss through disturbance and/ or displacement (including disruption to flight lines resulting from avoidance action). Mortality resulting from collisions with turbines or ancillary infrastructure. Stage one Determination of likely significant effect of the wind farm proposal, alone or in combination with other plans or projects At this stage, a competent authority will require at least the following basic information: First edition 15 October

2 existing bird data, other relevant information; and an appraisal of habitats and species likely to be present. (Since this technical information note is intended to provide guidance for dealing with wind farm applications that may affect the above listed SPA/ Ramsar sites, it should be assumed that site specific surveys will need to be undertaken) In most cases this should also allow Natural England to advise developers and Competent Authorities on the likely significant effect, alone or in combination, of the proposal on the SPA/Ramsar site(s). If deemed that the proposal is likely to have a significant effect then an Appropriate Assessment will be required. The information necessary to inform an Appropriate Assessment is detailed at stage two. Stage two Information required to inform an Appropriate Assessment For those proposals likely to have a significant effect on the above SPA/ Ramsar site(s), Competent Authorities are required to undertake an Appropriate Assessment. In carrying out their Appropriate Assessment, Competent Authorities require adequate information to assess the affect of the proposal on the integrity of the above site(s) in the light of its conservation objectives. 1 Desk-based study Compile existing bird data and other relevant information. 2 Appraisal of habitats and species likely to be present An assessment of land cover data, habitat survey data or site visit(s) by an experienced ornithologist familiar with bird-habitat associations can be useful in identifying the likelihood of the proposal affecting the relevant species. For example, crop type or other forms of agricultural land use can influence bird distribution and abundance and may vary through the course of a windfarms lifespan. Hence, assessments on farmland sites should include habitat surveys and use habitat associations (e.g. arable fields used as roost sites) to attempt to predict bird use of the site, and any changes in bird communities and impacts which may occur over the course of the wind farm lifespan. 3 Recommended standard survey methodologies and minimum survey effort for an Appropriate Assessment It is likely that a range of methods will be needed for each site, dependent on species and habitats present. Guidance should be sought from Natural England as to the most appropriate methods. The following identifies standard survey methodologies and monitoring requirements for key species associated with the Humber Estuary, Thorne & Hatfield Moors, Hornsea Mere and The Lower Dewent Valley SPA/ Ramsars. This is general guidance and constitutes without prejudice advice only. As stated above, it is not possible to be absolutely prescriptive in terms of precise methodologies as these will need to be developed on a case by case basis. The references cited in this document should also be consulted. Standard survey methodologies and monitoring requirements Wintering waders Species Include avocet, knot, dunlin, blacktailed godwit, redshank, bar-tailed godwit, oystercatcher, ringed plover, grey plover, sanderling, whimbrel, curlew, greenshank, turnstone, wood sandpiper, ruff, golden plover, lapwing, etc. NB. On SPAs/Ramsar sites classified for a wintering/ non-breeding waterbird assemblage, all wader species must be surveyed/ recorded. Survey method A winter survey method for lowland/farmland waders should be followed (at least two visits per month October to March inclusive). Page 2

3 Vantage Point watches 36 hours at each vantage point (VP) for the non-breeding season (Sept - mid-march inclusive). VP observations should be stratified according to tide height and should include observations conducted at night where appropriate. See SNH guidance (November 2005) for VP Radar studies are strongly recommended where species are nocturnally active. These should also record flight height information. Comments Most inter-tidal non-breeding waders continue to be active at night when flight behaviour can differ from daytime and flight behaviour can also vary with the state of the tide height and season. There may be substantial movement between mudflats and high tide roosts by day and night. Waders moving between tidal flats and inland roosts have been found to use different flight paths during the day and darkness. Thus when planning near tidal areas, nocturnal movements should be considered before locations for turbines are assigned. Obtaining data on nights when flights to or from roosts may coincide with high tides close to dawn or dusk may be particularly useful as these are key times when many species are most active. Surveys should attempt to discover the feeding and roosting sites of any birds that may potentially fly through or over the wind farm site. Migratory/passage waders Species Include knot, dunlin, black-tailed godwit, redshank, whimbrel, ruff, ringed plover etc. NB. On SPAs/Ramsar sites classified for a non-breeding waterbird assemblage, all wader species must be surveyed/ recorded. Survey method Surveys should be undertaken in at least one set of migration periods i.e. at least one spring migration period and at least one autumn migration period (see comments). Counts should be undertaken every week (see comments). Specific survey method should be agreed with Natural England depending on the key period for the particular species, e.g. where Ringed Plover are known to be present the survey period will need to be extended as they are still in good numbers during May, July and August. Vantage point watches Additional effort appropriately timed during migratory periods: 36 hours of observations at each VP for spring migration. 36 hours of observations at each VP for autumn migration. VP observations should be stratified according to tide height and should include observations conducted at night where appropriate. See SNH guidance (November 2005) for VP Radar studies are strongly recommended where species are nocturnally active. These should also record flight height information. Comments Spring migration period tends to occur between March to mid-may although, exact timings vary between species and broader weather patterns. Autumn migration period: September to November. As turnover can be high during migration, counts should be undertaken more frequently than for wintering birds, e.g. at least every week. Ruff qualifies during spring migration on the Lower Derwent Valley SPA. Breeding waders Species Avocet, ruff, spotted crake. Survey method Avocet single species method: 3 visits in May with a weekend between visits. CBC scaled down methodology for ruff and spotted crake: 3 visits from March to July. Spotted crake single species method: 3 visits, first half of May, second half of May and first half of June. Vantage point watches 36 hours of observation at each VP for the breeding season (e.g. mid- March to August) See SNH guidance (November 2005) for VP Comments Absence of nest sites from within a proposed wind farm site does not necessarily mean that there is no risk of the scheme affecting these species. Page 3

4 Wintering wildfowl Species Include shelduck, scaup, goldeneye, dark-bellied Brent goose, smew, whooper swan, slavonian grebe, mediterranean gull, shoveler, Bewicks swan, wigeon, teal, mallard, pochard, gadwall etc. NB. On SPAs/Ramsar sites classified for a wintering/ non-breeding waterbird assemblage, all wildfowl species must be surveyed/ recorded. Survey method Census methods e.g. WeBS, National wintering swan census, National censuses of geese, etc. Several visits through a winter will be necessary to determine usage, at least twice per month: October to March. Where Brent geese are thought to be present the survey period will need to be expanded to take account of them to include April /May. the nonbreeding season (October to March/April inclusive). VP surveys should cover representative times of the day and where possible some observations should be conducted during conditions of low cloud or mist as wildfowl will continue to fly under such circumstances. For sites which may potentially affect birds flying to and from roosts, observations should be conducted one hour before dawn to one hour after dawn and one hour before dusk to one hour after dusk. Where appropriate it is also important that the surveys are conducted across the tidal cycle. For sites close to feeding sites or that may intercept flights between feeding sites, observations should be conducted at additional hours of the day. See Comments If it is already known that flocks shift feeding or roost sites seasonally then more observations, concentrated in the period within the non-breeding season may be needed. If flocks are known to shift their feeding or roosting sites between winters then at least two winters of observation are needed, especially if there is no other detailed recent source of information on flock movements. If birds are not found to use the site as a feeding area on any observation day, searching for the location of the feeding area of wildfowl flock(s) away from the wind farm site will facilitate interpretation of the likelihood that birds may use the wind farm site. Similarly, searching the wind farm area and its environs for signs of wildfowl presence (counts of droppings) can help determine if feeding birds are using the wind farm site on days previous to survey visits. Breeding wildfowl Species Shoveler. Survey method Dabbling and diving ducks breeding season survey: 3 visits one month apart, early to mid-april, early to mid-may and early to mid-june. Vantage point watches 36 hours of observation at each VP during the pre-breeding and breeding season. Observations should be collected one hour before dawn to one hour after dusk. Some observations should be conducted during conditions of low cloud or mist as wildfowl will continue to fly under such circumstances and flight routes can vary with weather conditions. Comments If flight routes lie in the direction of the proposal site then additional VP watches should be conducted to estimate the number of flights which occur per day, to estimate collision risk. Absence of nest sites from within a proposed wind farm site does not necessarily mean that there is no risk of the scheme affecting these species. Wintering raptors Species Hen harrier. Survey method Single species method for hen harrier: visits from September to March. the non-breeding season (September to mid- March). See SNH guidance (November 2005) for VP Comments Where raptors are the main concern, studies need to focus on raptor ranges rather than just on the proposed wind farm site Page 4

5 to obtain more representative information on their use of the area. For non-breeding hen harrier roost observations should be undertaken in the first hour after dawn and in the last hour before dusk noting the flight behaviour (time, height, direction) of approaching and departing birds and birds flying around the roost site. Occupancy, numbers, flight lines and heights to and from the roost should be recorded. Observation effort should be spread evenly through the season unless a roost is known to be important for passage birds when effort should be more concentrated during the passage periods (September, October, and March). Breeding raptors Species Marsh harrier. Survey method Single species method for marsh harrier: 5 visits in total from mid- April to mid-june. the breeding season (mid-march to August). See Observations should be spread through the day between dawn and dusk and also temporally to account for all phases of the breeding cycle. Comments Absence of nest sites from within a proposed wind farm site does not necessarily mean that there is no risk of the scheme affecting these species. VP watches should aim to assess if flight routes lie in the direction of the proposal site. Information on breeding success over several years can be prove very useful in interpreting likely effects of wind farms on raptors. Particular attention to breeding display flights and the flight behaviour of dispersing young as birds may be prone to collision when engaged in these activities. Wintering - others Species Bittern. Survey method Single species method for bittern. - Areas of suitable habitat within the site. Vantage point watches 36hr at each VP. See methodology Breeding - others Species Bittern, nightjar, corncrake. Survey method Single species method for bitterns, nightjar and corncrake. CBC - Areas of suitable habitat within the site. Identification of possible nightjar feeding sites over a wide area (up to 5 km) in order to identify likelihood of movements towards them. Vantage point watches 36 hours of observation at each VP during the breeding season. See Comments Little information on nightjar behaviour in relation to windfarms exists. Radar surveys may be the most effective way of identifying behaviour around windfarm sites. Night vision equipment may also be useful for observing feeding birds. Radio tagging could also capture this information. Breeding - others continued Species Little tern. Survey method Not likely to correspond to wind farm site, however VP may be required. the breeding season (mid-may to late-june). See Comments Breeding terns can be very mobile in comparison to other seabirds. In some cases, whole colonies may shift location from year to year, or a large proportion of one colony may Page 5

6 move to a different colony in a different year. Pairs which fail at one colony early in the breeding season may even move to a different colony in the same season. Further information Natural England's policy position on sustainable energy Natural England propose to work proactively with the sustainable energy industry to identify areas of England where sustainable energy development can proceed in a manner that balances the long term benefits for the natural environment with any short term impacts, where this approach does not conflict with the statutory requirements of the Habitats Regulations. Natural England will provide its advice on the implications of any proposed sustainable energy infrastructure development based on a balanced assessment of: The impact of the infrastructure on the existing features of the natural environment. The changes to the existing features of the natural environment that will occur as a result of climate change which is already locked in. The potential for the infrastructure development to contribute to improving the resilience of the natural environment to further climate change. The contribution of the infrastructure to reducing greenhouse gas pollution. Contact details This note has been developed by the Yorkshire and Humber Government South and Maritime Team; Bull Ring House, Northgate, Wakefield WF1 3BJ. Tel: Natural England Technical Information Notes are available to download from the Natural England website: For information on other Natural England publications contact the Natural England Enquiry Service on or enquiries@naturalengland.org.uk Key Reference documents BIRDLIFE INTERNATIONAL ON BEHALF OF THE BERN CONVENTION Wind Farms and Birds: an analysis of the effects of wind farms on birds, and guidance on environmental assessment criteria and site selection issues. ENGLISH NATURE Wind farms and Birds. Bird Network Information Note. GILBERT, G., GIBBONS, D.W., & EVANS, J Bird Monitoring Methods: a manual of techniques for key UK species. RSPB/BTO/WWT/JNCC/ITE/The Seabird Group. LANGSTON, R Wind Energy and Birds: Results and Requirements. RSPB Research Report, No.2 SNH Survey methods for use in assessing the impacts of onshore wind farms on bird communities. Scottish Natural Heritage. Page 6