Wansbeck Blyth Harbour Wind Farm Ornithological Monitoring Programme: Wintering Bird Surveys 2016-17
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WANSBECK BLYTH HARBOUR WIND FARM ORNITHOLOGICAL MONITORING PROGRAMME: WINTERING BIRD SURVEYS 2016-17 Clockwise from top left: Black-headed gull, cormorant, great black-backed gull and eider © Steve Percival Steve Percival, Tracey Percival and Tom Lowe Ecology Consulting, Swallow Ridge Barn, Old Cassop, Durham DH6 4QB Email: [email protected] October 2017 WANSBECK BLYTH HARBOUR WIND FARM ECOLOGY CONSULTING POST-CONSTRUCTION WINTERING BIRD SURVEY 2016-17 October 2017 WANSBECK BLYTH HARBOUR WIND FARM ORNITHOLOGICAL MONITORING PROGRAMME: POST-CONSTRUCTION WINTERING BIRD SURVEYS 2016-17 Introduction 1. The Wansbeck Blyth Harbour wind farm has a planning consent condition (Condition 17) that requires a scheme of the post-construction monitoring of waders and their feeding and roosting habitats to be implemented. This states that: “(a) Prior to the commencement of construction of the wind farm hereby approved, a scheme of post-construction monitoring of wader habitats and roosting habitats shall be submitted to and approved in writing by the Local Planning Authority. The scheme shall be written in association with the County Ecologist, Natural England and the RSPB and shall identify any measures required to enhance wader habitats and to ensure that sufficient roosting habitats are made available within the immediate area. The scheme shall then be implemented as approved. (b) The scheme submitted pursuant to condition 17(a) shall cover the period from the construction of the first turbine, throughout the 60 months construction period and for an additional 36 months following the construction of the final turbine.” 2. This document reports on the last of the three winters of post-construction monitoring that are being undertaken to satisfy Condition 17. The programme follows the principles of SNH (2009) and Natural England (2010) guidance regarding post-construction monitoring of birds at wind farms. It focuses on the key issue at this site, potential effects on wintering waterfowl (including waders). This includes collision risk (though this was largely predicted to be lower as a result of the removal of the existing turbines and replacement of smaller number of large machines) and disturbance of feeding and roosting birds. 3. The main aim of this work is to test the predictions made in the ES, to confirm the effectiveness of the mitigation measures and to provide information to fine-tune the proposed wader habitat enhancement plan. The work follows the same methodologies as the baseline surveys in order to directly compare the numbers and distribution before and after the removal of the old turbines and the construction of the new one. All of the nine previous turbines have been removed but only one of the new ones has been constructed. Its location is shown in Figure 1. The turbine is a RePower 3.4MW XM104, 128m to tip and with a 104m rotor diameter (with a variable rotational speed of 7.1 – 13.8 rpm). The ‘post- construction phase of this work therefore represents two changes that have taken place since the pre-construction baseline (a) replacement of one of the existing 330kW turbines with one 3.4MW machine, and (b) removal of the other 8 old 330kW turbines. The survey area includes three zones; the ‘Replacement Zone’, where the original turbines have been replaced with a single larger turbine, the ‘Removal Zone’, where the original turbines have been removed but not replaced, and the ‘Reference Zone’ outside the area affected by any of these changes to the Blyth Harbour wind turbines. Survey Area 4. The same survey area is being used as for the pre-construction baseline wintering bird surveys. This was originally chosen to include all areas within the potential zone of Page | 2 WANSBECK BLYTH HARBOUR WIND FARM ECOLOGY CONSULTING POST-CONSTRUCTION WINTERING BIRD SURVEY 2016-17 October 2017 ornithological influence of the proposed wind farm plus a buffer zone around that. Its extent is shown in Figure 1. That Figure also shows the locations of the sectors used in the count survey. Wintering Bird Surveys 2016-17: Methods 5. Two winters’ baseline surveys were undertaken in 2005/06 and 2007/08, when the original wind turbines were operational and before installation of the new turbine. Further surveys were carried out in 2014-15, 2015-16 and in 2016-17, following removal of the original turbines and installation of the new turbine. The 2014-15, 2015-16 and 2016-17 surveys followed the same survey methodology as previously undertaken and reported in the ES; (a) a field survey based on a simple ‘look-see’ method, counting the bird numbers within the pre-defined study area (Gilbert et al. 1998) by sectors, and (b) a vantage point survey, monitoring bird flight activity to quantify movement rates across the study area. The latter focus on the wind farm collision risk zone, and include daytime movements and dawn/dusk roost flights. A range of tidal states was captured in the survey schedule, as per the original surveys. Bird counts 6. This survey work comprised regular counts of the birds within the wintering bird study area. Twelve of these surveys were undertaken at approximately fortnightly intervals between September 2016 and March 2017. The counts were carried out as instantaneous counts, recording a snapshot of the birds present in each field at the time it is surveyed. One such count of each sector was made each survey day, recording the numbers of all the key species present. Any additional records made outside this time were noted as supplementary records. These snapshot counts were organised to ensure that the full range of times of day were covered in each part of the study area. The following target species were recorded: ▪ All ducks, geese, swans, cormorants, herons, coot and grebes; ▪ All waders (including lapwing and golden plover); ▪ All birds of prey and owls; ▪ Large flocks (>100 birds) of other species (except woodpigeon and rook); ▪ Any other notable species. 7. As well as counting each species, the behaviour of each flock was also recorded, e.g. feeding/roosting. Birds in flight over-flying the field during the snapshot were also recorded, together with an estimate their height and direction. Vantage point surveys 8. These were carried out to compare key species flight activity through the wind farm site and its surrounds with that prior to construction. A single vantage point was used (as only a single turbine has been constructed) to observe bird movements through in the vicinity of the single constructed wind turbine and its surrounds (with at least 500m). The survey methodology followed the same standard SNH-recommended survey method (Madders, in Whitfield et al. 2010) as used in the pre-construction surveys. That methodology was refined to record flight height estimates as accurately as possible rather than just summarising them to height classes. The target species for these surveys comprised all of the SPA/SSSI species, Page | 3 WANSBECK BLYTH HARBOUR WIND FARM ECOLOGY CONSULTING POST-CONSTRUCTION WINTERING BIRD SURVEY 2016-17 October 2017 but any other species of conservation importance were also recorded. All target species flight lines were mapped, and the flight height of each flock recorded. When birds were observed over an extended period, estimates of flight height were recorded every minute. The activity during each flight (e.g. flying to roost, foraging) was also recorded. Approximately nine hours VP survey were carried out each month, with the timing of these observations made to cover dawn/dusk roost flights as well as general daytime movements, and over the full range of tidal conditions, with a total VP survey time of 54 hours. Collision Monitoring 9. Carcass searches were carried out on an approximately fortnightly basis through the September-March survey period. The collision monitoring methodology followed that developed in the USA for bird collision monitoring at wind farms (Morrison 1998). A core area of 128m radius around each turbine was searched carefully on foot where accessible - see Figure 2 - the maximum tip height of the turbine (following Natural England guidance, Drewitt 2010). Of this 128m radius 2.3ha (44%) was terrestrial habitat above the high water mark, so it was assumed that survey coverage was 44% of the possible area in which collision victims may have occurred. 10. Sectors around the turbine were searched slowly, taking particular care to search any taller clumps of vegetation, and openings of animal burrows. The precise location of any dead bird found was recorded and mapped (by reference to the distance and direction to the nearest wind turbine, and using a GPS). All carcasses were photographed, and their details recorded as follows. For all casualties found, data recorded would include species, sex, age, date and time collected, location, distance and direction (degrees) to nearest turbine, condition, and any comments regarding possible causes of death. The condition of each carcass found should be recorded using the following condition categories: ▪ Intact - carcass that is completely intact, is not badly decomposed, and shows no sign of being fed upon by a predator or scavenger. ▪ Scavenged - entire carcass that shows signs of being fed upon by a predator or scavenger or a portion(s) of a carcass in one location (e.g., wings, skeletal remains, legs, pieces of skin, etc.). ▪ Feather Spot - 10 or more feathers at one location indicating predation or scavenging. 11. Carcasses were left in situ in order to provide further information on decay rates and detectability. As only a small number of collision victims were found, these were supplemented by a sample of birds shot by a gamekeeper provide more information on the rate of carcass removal and to test observer search efficiency. Two woodpigeons and a carrion crow were set out on 1/11/16 within the search areas around the wind turbine and recorded as part of the corpse monitoring.