waterfowl numbers, usage and distribution of the river shannon … · 2017-12-22 · waterfowl...

Waterfowl Numbers, Usage and

Distribution of the River Shannon and the River Fergus Estuaries

Interim Report

DOCUMENT DETAILS Client: Clare County Council Project title: CCC - Bird Usage Survey Data Shannon-

Fergus Estuary

Project Number: 170160 Document Title: Waterfowl Numbers, Usage and

Distribution on the River Shannon and River Fergus Estuaries

Doc. File Name: IR D2 – 2017.11.28 - 170160 Prepared By: McCarthy Keville O’Sullivan Ltd.

Planning & Environmental Consultants Block 1, G.F.S.C. Moneenageisha Road, Galway

Document Issue: Rev Status Issue Date Document File Name Author(s) Approved By:

01 Draft 02/11/2017 IR D1 – 2017.11.02 - 170160 AA DO’D

01 Draft 28/11/2017 IR D2 – 2017.11.28 - 170160 AA DO’D

This project is support by the Clare County Heritage Plan 2011-2017 and is partly

funded by the Heritage Council.

McCarthy Keville O’Sullivan Ltd. – Planning & Environmental Consultants

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Table of Contents

1 Introduction ............................................................................................ 1 1.1 General Project Overview and Objectives ................................................................. 1

1.2 Site Description and Importance .............................................................................. 1

2 Methodology ........................................................................................... 3

2.1 Preparation and Project Initiation ............................................................................ 3

2.2 Survey Team Workshop and Recce Visit ................................................................... 3

2.3 Survey Methodology .................................................................................................. 4

2.4 Data Management and Analysis ................................................................................ 7

2.5 GIS Data Analysis ...................................................................................................... 8

3 Interim Results and Limitations ............................................................. 9

3.1 Survey Progress and Constraints ............................................................................. 9

3.2 Interim Results ......................................................................................................... 9 3.2.1 Species recorded..................................................................................................... 9 3.2.2 Peak numbers recorded ....................................................................................... 10 3.2.3 Average Subsite Percentage Occupancy .............................................................. 10 3.2.4 Average Percentage Area Occupancy ................................................................... 10 3.2.5 Species Richness .................................................................................................. 11 3.2.6 Waterbird distribution-subsite ranking ................................................................ 11 3.2.7 Foraging/Roosting Density Mapping .................................................................... 11 3.2.8 Flock mapping ....................................................................................................... 11 3.2.9 Intertidal Foraging Density ................................................................................... 12 3.2.10 Coverage of SIFP areas ..................................................................................... 12 3.2.11 Species summaries ........................................................................................... 12 3.2.12 Disturbance ....................................................................................................... 12

4 Discussion ............................................................................................ 13

References .................................................................................................. 14

Appendices

Appendix 1 SPA Site Synopsis Appendix 2 Recording Form Appendix 3 Dot Density Maps - All Surveys Appendix 4 Flock Maps - High Tide Surveys

Bird Usage Survey Shannon-Fergus Estuary IR D2 – 2017.11.28 - 170160


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1 INTRODUCTION

1.1 General Project Overview and Objectives McCarthy Keville O’ Sullivan have been commissioned to carry out a bird usage survey of the River Shannon and River Fergus Estuaries Special Protection Area (SPA) comprising the entire estuarine habitat from Limerick City westwards as far as Doonaha in Co. Clare and Dooneen Point in Co. Kerry with an additional area westwards on the north and south shore to encompass SIFP areas, as detailed below. This survey has been commissioned under the auspices of the Strategic Integrated Framework Plan (SIFP) for the Shannon Estuary 2013-2020, an inter-jurisdictional land and marine-based framework to guide the future development and management of the Estuary. This plan identifies Strategic Development Locations for marine-related industry and Areas of Opportunity for aquaculture and renewable energy generation. Appropriate Assessment of any future developments requires that the most up-to-date and comprehensive geospatial data on bird populations is available. Due to the size and complexity of the SPA, there have been problems in the past in carrying out a full and comprehensive survey of the site, as detailed in Lewis et al. (2016). The most complete ground-based survey of the estuary was undertaken in 2010/2011 by the National Parks and Wildlife Service (NPWS) as part of their Waterbird Survey Programme, which used 66 different count subsites across the estuary. I-WeBS counts have also taken place, although coverage of a maximum of only 25 subsites was achieved in one season with ten or less subsites counted in 12 seasons. Although the NPWS survey is currently the most complete survey of the site undertaken, it was not without limitations and not all subsites were covered (Lewis et al. (2016), including those containing SIFP areas. The objectives of this survey are to record bird usage across the entire estuary, allowing data from discrete subsites to be compared with one other, with a particular focus on the SIFP identified areas. Where possible, subsites used in previous NPWS and Irish Wetland Bird Surveys (I-WeBS) have been used, with additional sites to give further coverage and some subsites modified to include SIFP areas. The methodology used follows that given in Lewis & Tierney (2014).

1.2 Site Description and Importance The River Shannon and River Fergus Estuaries SPA comprises the entire estuarine habitat from Limerick City in the East and Doonaha in Co. Clare and Dooneen Point in Co. Kerry in the West. It consists of vast expanses of intertidal mudflats holding a rich invertebrate community that provides an important food source for wintering and passage waterbirds. The SPA has a total area of 32,252 ha. The site is the largest estuarine complex in Ireland and is considered to be the most important coastal wetland site in the country, regularly holding over 50,000 waterfowl during the winter including internationally important populations of pale-bellied brent goose, dunlin, black-tailed godwit and redshank. A further 17 species are also described on the NPWS website (www.npws.ie) as ‘Features of Interest’ of the SPA; these being cormorant, whooper swan, pale-bellied brent goose, shelduck, wigeon, teal, pintail, shoveler, scaup, ringed plover, golden plover, grey plover, lapwing, knot, dunlin, black-tailed godwit, bar-tailed godwit, curlew, redshank, greenshank and black-headed gull. Three of these species are also listed on Annex I of the E.U. Birds



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Directive, these being whooper swan, golden plover and bar-tailed godwit. The SPA Site Synopsis is given in Appendix 1.



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2 METHODOLOGY

2.1 Preparation and Project Initiation A map showing the subsites that have been used during previous and current surveys, including previously used subsites and new subsites, is presented in Figure 1. In so far as possible, the selected subsites have followed those used during the NPWS survey in 2010/2011. Twenty-one additional subsites have been added to cover areas within the SIFP area that have not been previously surveyed and one area that forms part of the SPA but is not covered by the SIFP area has also been included in the current study area. These are shown in Figure 1 in green. Additional subsites were added in most cases to facilitate comparison with previous data. However, the boundaries of four subsites were altered slightly to cover small parts of the SPA that were not counted during the previous NPWS survey. These are shown in pink in Figure 1. Areas of the SPA that are not countable from land (over two kilometres from the shore) were not included as they were not within survey distance of the shore. The new subsites are of a manageable size and their boundaries have easily identifiable, named features. The target species for the study comprise the species listed as Special Conservation Interests of the SPA in the Conservation Objectives document for the River Shannon and River Fergus Estuaries SPA. However, all waterbirds are recorded during surveys.

Following an initial meeting between the MKO project team and representatives from Clare County Council (CCC), acting on behalf of the SIFP Steering Group, and NPWS, maps were created showing all subsite boundaries routes and vantage points. Subsite code numbers that were used by NPWS during the Waterbird Survey Programme were retained for this project to allow easy comparison with data from this survey. New code numbers were used for new section. All subsites and their respective codes are shown in Figure 2.

2.2 Survey Team Workshop and Recce Visit A workshop for the survey team was hosted by MKO prior to the commencement of surveys, in conjunction with a recce visit for all surveyors to their relevant survey areas. This allowed the project manager to make a presentation confirming the details of the required methodology including the manner in which data should be recorded, entered and submitted, to discuss health and safety issues and practical arrangements, to discuss any site-specific aspects of the surveys and to respond to any queries from surveyors. Each surveyor was also presented with a survey pack with fieldsheets, methodology, maps and all pertinent information such as contact details of the survey team and health and safety information. Surveyors were also given all survey dates and times and a letter from Clare County Council explaining the survey to landowners and the public. A recce visit involving all surveyors and the Project Manager followed this workshop. Each surveyor was given maps of their designated subsites with proposed subsite boundaries and vantage points and the suitability of these in the field was assessed. As well as this information, accessibility of the survey locations was also assessed by each individual surveyor and initial contact with landowners was undertaken. Clare County Council also assisted with access arrangements in some areas, particularly around Shannon Airport and other sites including ports, power stations and areas of industry, where health and safety inductions were required.

McCarthy Keville O'Sullivan Ltd., Block 1, G.F.S.C, Moneenageisha Road, Galway, Ireland. Email: [email protected] Tel: +353 (0)91 735611 Fax: +353 (0)91 771279

MAP TITLE:

PROJECT TITLE:

DRAWING BY: CHECKED BY:

MAP NO.:

ISSUE NO.:

SCALE:

DATE:

Ordnance Survey Ireland Licence No. AR 0021817© Ordnance Survey Ireland/Government of Ireland

Stephen Corrigan Alex Ash01-11-2017

1:250,000

170160-2017.01.11-F

Figure 1Subsite Categories 2010 - 2017170160 - Shannon Fergus Estuary

Map Legend

Previous sub-sites used in 2010/11NPWS Waterbird Survey Programme

Shannon Estuary SPA

Modified NPWS sub-sites

New Sub-sites

McCarthy Keville O'Sullivan Ltd., Block 1, G.F.S.C, Moneenageisha Road, Galway, Ireland. Email: [email protected] Tel: +353 (0)91 735611 Fax: +353 (0)91 771279

MAP TITLE:

PROJECT TITLE:

DRAWING BY: CHECKED BY: ISSUE NO.:

SCALE:

DATE:

Ordnance Survey Ireland Licence No. AR 0021817 © Ordnance Survey Ireland/Government of Ireland

Stephen Corrigan Alex Ash

01-11-20171:280000

170160-2017.11.01

Sub-site Designations170160 - Shannon Fergus Estuary

Fig: 2



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2.3 Survey Methodology A total of 14 surveyors conduct the field survey over the whole site over two days on each of the eleven surveys. As well as these 14 surveyors, the Project Manager is also present on site to assist and ensure coverage is completed in the event of a surveyor being unable to attend or requiring assistance to complete a count. As well as the core 14 surveyors, a stand in surveyor has been used on three occasions when a core surveyor was unable to be present. Any substitute surveyors are communicated and agreed in advance with the SIFP representative. A text messaging group is used by the project manager to keep in touch with surveyors. Group emails are also used, as required, to communicate with the survey team. Each surveyor covers a maximum of 10 kilometres of shoreline on each day as, based on the experience of the survey team, any more than this is not manageable in the four-hour timescale available. The same surveyor is allocated the same pre-designated subsites on each of the surveys to achieve continuity. This allows surveyors to become well acquainted with their subsites and develop good relations with landowners. Optimum dates were chosen and these are given in Table 1 below. These were chosen to give an even distribution of surveys over the entire study period on dates on which the low/high tide falls as close to midday as possible. Consideration was also given to avoiding weekends and bank holidays when surveyors may not be available and leaving at least one date in each relevant period free to allow for a back-up date if weather forces a cancellation. Tide times used are those for Foyne Island. Table 1. Survey Schedule

Count No Count Period Tide stage Date Day Tide Height

Tide time

1 May-July High 18/05/2017 Thursday 4.0 11:50

19/05/2017 Friday 4.0 13:03 2 May-July Low 22/06/2017 Thursday 0.3 11:04 23/06/2017 Friday 0.2 12:013 August-

September High 29/08/2017 Tuesday 4.2 12:06

30/08/2017 Wednesday 4.0 13:14

4 August-September

Low 04/09/2017 Monday 1.1 11:41

05/09/2017 Tuesday 0.8 12:20

5 October-February

Low 18/10/2017 Wednesday 0.4 12:01

19/10/2017 Thursday 0.3 12:35 6 October-

December High 27/11/2017 Monday 4.1 12:09

28/11/2017 Tuesday 4.2 13:28 7 October-

February Low 18/12/2017 Monday 0.7 12:00

19/12/2017 Tuesday 0.7 12:35 8 January-

February High 25/01/2018 Thursday 4.5 11:40

26/01/2018 Friday 4.4 12:569 October-

February Low 01/02/2018 Thursday -0.2 12:34

02/02/2018 Friday -0.3 13:1710 March-April Low 01/03/2018 Thursday -0.1 11:30



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Count No Count Period Tide stage Date Day Tide Height

Tide time

02/03/2018 Friday 0.4 12:04 11 March-April High 23/04/2018 Monday 4.5 13:11 24/04/2018 Tuesday 4.2 14:41

The survey methodology rigorously follows that of Lewis & Tierney (2014). A summary of the methods used is given here with a full description being found within that document. Waterbirds are counted on the dates given in Table 1 within a two -hour period either side of low/high tide on the ‘look-see’ basis (Bibby et al., 2000) and major flocks are also recorded on field maps. The number of each species recorded in each of the given subsites is recorded with numbers divided into four broad habitat types that birds were recorded in and also divided between those that were foraging and those that were roosting. A combination of low and high tide counts is used due to the differences in behaviour and site usage between tidal states, with different species likely to be foraging and roosting in different areas of the estuary depending on the stage of the tidal cycle. Surveyors are provided with detailed maps of their sub sections which clearly show the boundaries of each subsite and the extent of each of four tidal habitat types, an example of which is given in Figure 3. A definition of each of the tidal habitats is provided in Table 2. Field recording forms were also provided (Appendix 2). The boundaries of tidal habitats for new survey sections in the Shannon Estuary were determined by reviewing habitat maps provided by the NPWS, aerial photography of the Shannon Estuary and records provided by surveyors from the recce visits during April 2017.

Figure 3 Example of subsite map showing tidal habitats



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Following discussions with NPWS and Clare County Council, acting on behalf of the SIFP Steering Group, it was decided to record waterbirds in any terrestrial areas 500m inland from the estuary. Although not all such areas are within the SPA, waders and wildfowl are likely to use these areas for feeding and roosting and important populations associated with the SPA (and SIFP areas) may otherwise go unrecorded.

Table 2 Definition of broad habitat types used (following NPWS, 2012)

Broad Habitat Type

Broad Habitat Description

Intertidal Refers to the area uncovered by the tide and most likely dominated by mudflats and sandflats. It may also include areas of rocky shoreline, areas of mixed sediment and gravel/pebbles or shingle and gravel shores.

Subtidal Refers to areas that are covered by seawater during counts. During low-tide counts it will include offshore water, tidal channels and creeks as well as tidal rivers.

Supratidal This category pertains to the shore area and habitats immediately marginal to and above the mean high-water mark. The supratidal section is an integral part of the shoreline. This broad habitat also includes areas of saltmarsh where the saltmarsh is contiguous with coastal habitats lying above. Note that patches of lower saltmarsh (e.g Spartina sp.) surrounded by intertidal flats, were included in the intertidal category.

Terrestrial Used where birds were recorded within habitats close to the shoreline but were above the intertidal and supratidal levels. Includes aquatic habitats that are not tidal that occur within the study area (i.e brackish lagoons, freshwater lakes)

Significant flocks are recorded, with surveyors required to use their judgement to decide what might constitute a significant flock for each species, as prescribed in Lewis & Tierney (2012). The project manager is open to consultation on this subject and a precautionary approach is taken. These maps along with the recording form allow the spatial extent of each flock to be mapped, as well as the number of each species. Following Lewis & Tierney (2012), in addition to bird distribution data, other accessory information gathered includes the presence of any activities causing disturbance to waterbirds. The following categories are used:

1. Human, on foot – shoreline 2. Human, on foot – intertidal aquaculture, 3. Bait-diggers, 4. Non-powered watercraft, 5. Powered watercraft, 6. Water-based recreation, 7. Horse-riding, 8. Dogs, 9. Aircraft, 10. Shooting, 11. Other, 12. Winkle-pickers, 13. Aquaculture machinery, and



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14. Other vehicles. The level of disturbance caused by each activity is also recorded with the following letters denoting the response by each species to each disturbance type. W - Weak response, waterbirds move slightly away from the source of the disturbance. M – Moderate response, waterbirds move away from the source of the disturbance to another part of your subsite; they may return to their original position once the activity ceases. H – High response, waterbirds fly away to areas outside your subsite and do not return during the current count session. The length of the activity is also recorded using the codes A-D, as shown below, and a record is made as to whether the activity was already occurring within the subsite when the count started. A – short/discrete event. B – activity occurs for up to 50% of the count period. C – activity length estimated at >50% but <100% of the count period. D – activity continues after the count period has ended. Any raptors encountered are also recorded and it is noted whether their presence causes any disturbance to waterbirds.

2.4 Data Management and Analysis Surveyors were provided with a customised spreadsheet for data entry, to ensure standardisation of data collected and increase the efficiency of data entry and returns. Surveyors are also instructed to send all maps to MKO immediately after each survey for digitisation by trained staff. The data management team at MKO compile and quality check all incoming data. Subsite totals are obtained by summing individuals counted across each behaviour and broad habitat type within each subsite. For each survey undertaken, totals for each target species were obtained by summing all individuals across all habitat and behaviour types in each subsite. Monthly site totals were also obtained by summing all individuals of that species across all subsites in each month. Analysis will be carried out for each survey date using the total numbers of birds and the total numbers of foraging birds and roosting birds from the high and low tide bird surveys. This will allow each of the subsites to be compared with respect to these figures and the proportional use of each subsite by each Special Conservation Interest species to be ranked, with each subsite being ranked as Very High, High, Moderate or Low importance in accordance with Lewis and Tierney (2014). The definition of each ranking is given in Table 3 below. Table 3 Subsite rank position categories

Rank Meaning Very High (V) Any section ranked as 1 High (H) Top third of ranking placings Medium (M) Mid third of ranking places Low (L) Lower third of ranking places



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2.5 GIS Data Analysis Data is analysed to show the distribution of waterbirds within the two estuaries during each survey. Areas that are important for roosting and foraging can be identified for each species, with broad habitat types being mapped within sub site boundaries. The following analyses are carried out using MS Excel and MapInfo:

1. All data from low and high tide counts is processed using dot density programmes in MapInfo. Data will be presented as the density of a specific species within each subsite and its constituent habitat types. This will create one larger thematic map indicating the numbers of birds of that species within each site and habitat and this will be carried out for each of the 11 surveys. (Note this indicates the numbers present and not the exact position of waterfowl).

2. Flocks recorded at high tide will be mapped in MapInfo and the relevant data will also be imported from MS Excel. A thematic map can then be created indicating the species and number of each flock (This will indicate the position and relative size of each flock).



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3 INTERIM RESULTS AND LIMITATIONS

3.1 Survey Progress and Constraints Five complete surveys have taken place to date, as shown in Table 4 below. This section discusses the results of the four surveys completed in the months of May, June, August and September, as it would not have been possible to obtain all data from surveyors for the October count and check and compile it before the reporting deadline. Table 4. Surveys completed at time of interim report

Count No

Count Period Tide stage

Date Day Tide Height

Tide time

1 May-July High 18/05/2017 Thursday 4.0 11:50 19/05/2017 Friday 4.0 13:032 May-July Low 22/06/2017 Thursday 0.3 11:04 23/06/2017 Friday 0.2 12:013 August-

September High 29/08/2017 Tuesday 4.2 12:06

30/08/2017 Wednesday 4.0 13:144 August-

September Low 04/09/2017 Monday 1.1 11:41

05/09/2017 Tuesday 0.8 12:205 October-

February Low 18/10/2017 Wednesday 0.4 12:01

19/10/2017 Thursday 0.3 12:35 There have been no major obstacles in completing surveys to date. The weather has been mostly favourable, with no instances of poor visibility or very strong wind or rain that may have hampered survey effort. The project manager was required to fill in on one occasion during the June survey in Subsite ON023, due to a car breakdown experienced by the designated surveyor for that subsite. The project manager will continue to be available to assist with surveys as required, for example where subsites are particularly demanding due to access issues or where large areas of intertidal habitat hold large concentrations of birds. Two very small subsites were missed in one month each due to surveyor error (ON012 & OI458) and subsite OH418 was not completed in June due to health and safety concerns as there were bulls within the survey area. This will be fully discussed within the final report. It should be noted that there are limitations associated with presenting preliminary results, as many outputs rely on the results from all surveys as either a total, mean, peak or average count. Where results are not given, a description of what will be provided in the final report is provided below.

3.2 Interim Results

3.2.1 Species recorded A total of 46 waterbird species have been recorded so far during the months of May, June, August and September across two high-tide and two low-tide surveys. All SCI species of the River Shannon and River Fergus SPA were recorded, with the exception of whooper swan, light-bellied brent goose, pintail and scaup, all winter visitors which



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are unlikely to be encountered in Ireland during the survey months to date. Table 5 presents those SCI species which were recorded on a monthly basis, as well as their total numbers as discussed in Section 3.2.2, below.

3.2.2 Peak numbers recorded In the final report, the peak number of each SCI species recorded across all subsites during the low tide surveys and the high tide surveys (i.e. the highest count in any one survey) will be presented. Table 5 presents the total number of each species recorded across all subsites during the surveys in May, June, August and September. It should be noted at this stage that, with the possible exceptions of black-tailed godwit and greenshank, it is likely that all SCI species will not reach their peak counts until the winter months. Table 5 Total number of each SCI species recorded in each month across all subsites

Survey Month SCI Species May June August September Cormorant 494 383 442 321 Whooper Swan 0 0 0 0 Light-bellied brent goose

0 0 0 0

Shelduck 334 191 21 98 Wigeon 8 4 25 8 Teal 0 9 314 373 Pintail 0 0 0 0 Shoveler 3 0 0 0 Scaup 0 0 0 0 Ringed plover 7 62 5 281 Golden plover 0 0 192 0 Grey plover 5 0 20 3 Lapwing 0 0 46 128 Knot 0 0 36 55 Dunlin 28 0 768 832 Black-tailed godwit 1278 230 1511 3440 Bar-tailed godwit 14 0 59 49 Curlew 56 452 2253 2873 Redshank 2 24 1136 1131 Greenshank 0 2 205 177 Black-headed gull 249 1326 5827 8218

3.2.3 Average Subsite Percentage Occupancy Average Subsite Percentage Occupancy is defined as the average percentage of subsites in which a species occurred during low tide counts. This does not take the size of the subsites in to consideration. As this relies on an average from all months of the survey, it is not possible to produce figures for this measure at this stage, but this will be provided for all SCI species in the final report.

3.2.4 Average Percentage Area Occupancy Average Percentage Area Occupancy is defined as the average proportion of the total count area that a species occurred in during low tide counts. This takes in to consideration the areas of each of the subsites, which vary greatly. This calculation



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also relies on an average across all counts, which at this stage would not be useful but will be provided in the final report for all SCI species.

3.2.5 Species Richness The total number of waterbird species recorded across all subsites ranged from 28 species in June to 42 species in August, with 33 species recorded in May and 34 species recorded in September. In the final report, a calculation of species richness at a subsite level will be performed to express average diversity for each subsite. However, the calculation relies on a complete dataset from all surveys to calculate an average figure. MKO will produce a list of the top ten subsites based on highest average diversity for the high tide and low tide counts and overall peak diversity.

3.2.6 Waterbird distribution-subsite ranking As discussed in Section 2, the proportional use of each subsite by each of the SCI species will be determined thus allowing each of the subsites to be assessed and its relative importance ranked at high tide and low tide with the varying stages of the tide during these counts (falling and rising as well as high and low), ensuring that foraging areas at all stages of the tide are taken in to consideration. Tables will be provided that rank the proportional use of each subsite as Very High, High, Medium or Low using the following variables: Total numbers during low tide surveys (across all behaviours and habitats). Total numbers during high tide surveys (across all behaviours and habitats). Total numbers foraging intertidally within low tide surveys. Total numbers foraging intertidally within high tide surveys (intertidal areas

are exposed on the rising and falling tide). Total numbers foraging subtidally within low tide surveys. Total numbers (roosting/other behaviour) within low tide surveys.

The following outputs will be ranked as a number rather than Low, Medium or High: Rank average intertidal foraging density Ranked total numbers for high tide surveys across all habitats Total numbers (roosting/other behaviour) within high tide surveys

3.2.7 Foraging/Roosting Density Mapping Dot density maps showing foraging or roosting/other distribution for Special Conservation Interest species within each tidal habitat are given in Appendix 3. At this stage of the survey, it is possible to present dot density maps for the months that have been surveyed to date. Maps for all SCI species for all of the eleven surveys will be presented in the final report.

3.2.8 Flock mapping To allow comparison with the NPWS high tide survey in 2010/2011, flocks were mapped using the same methodology as described in Lewis & Tierney (2012). Tables and maps are presented for the two high tide surveys (May and August) in Appendix 4, with the location and extent of all significant flocks of SCI species shown with colour coding representing the size of each flock. Flock maps will be provided for further high tide surveys in the final report.



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3.2.9 Intertidal Foraging Density Intertidal foraging density will be calculated for each species by dividing the number of the species within a subsite by the area of intertidal habitat within the given subsite. The figure given will constitute the peak intertidal foraging density across all surveys. The whole site intertidal foraging density will also be calculated by summing the mean subsite counts for each species and dividing by the total area of subtidal habitat.

3.2.10 Coverage of SIFP areas In the final report each of the SIFP areas identified as Strategic Development Locations for marine-related industry and Areas of Opportunity for aquaculture and renewable energy generation will be discussed. The relative rankings and importance of the subsites in the context of the whole estuary taking in to consideration all of the variables discussed in Sections 3.2.1 to 3.2.9 will be reviewed.

3.2.11 Species summaries Species summaries for all SCI species will be presented in the final report to include the total numbers recorded (including a different figure for birds within the SPA boundary), which subsites each species was recorded in, their foraging distribution and their roosting distribution and a discussion on their status and distribution across the estuary.

3.2.12 Disturbance As discussed in Section 2.3, any activities that may cause disturbance to waterbirds within the subsites have been recorded with the level and frequency of disturbance noted. This will facilitate identification of those subsites most prone to disturbance.



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4 DISCUSSION

To date, there have been very few problems or issues relating to the gathering of data during the surveys, given the number of fieldworkers involved and the amount of land that needed to be accessed. As discussed in Section 3.1, three subsites have not been surveyed during one month, one due to the presence of livestock where health and safety was a concern and two very small subsites where the surveyor mistakenly believed they did not need to be counted. The data will be managed in such a way that any missing sections are taken in to consideration. It is very difficult to draw any conclusions on bird usage at this stage of the survey, as all results rely on the findings of all of the surveys and most species will not reach their peak numbers on the estuary until the winter months with whooper swan, light-bellied brent goose, pintail and scaup not recorded to date. There are some broad comments that can be made at this stage regarding species numbers during passage periods on the estuary. Previous surveys, including the NPWS Waterbird Survey carried out in 2010/2011, were carried out in the period between October and March and one of the aims of this survey is to provide coverage during spring and autumn passage periods. All of the surveys completed to date were conducted during passage periods with the exception of the June survey. Four species were recorded in numbers higher than those given as five year mean peak counts for the period 1995/1996 to 1999/2000 by NPWS (2015); black-tailed godwit, ringed plover, curlew and black-headed gull. With greater coverage, it is to be expected that an increase in numbers of some birds will be recorded. However, the large numbers of black-headed gulls (8,218) were unprecedented. It will be interesting to note whether these numbers decrease over the winter. Over 1,000 black-tailed godwit were recorded in May and August and over 3,000 in September indicating this species is using the estuary as a staging area during passage periods. Over 2,000 curlew were found in August and September also indicating the estuary is important for this species during the autumn passage period. It is worth noting that surveys that will take place in March and April 2018 will also occur during the spring passage period at a time of peak spring migration of some species including black-tailed godwit and whimbrel. Surveys will continue on a monthly basis between November 2017 and April 2018.



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REFERENCES

Boland, H and Crowe, O (2012) Irish Wetland Bird Survey: waterbird status and distribution 2001/2 -2008/09. BirdWatch Ireland, Kilcoole, Co. Wicklow. Boland et al. (2010) Whooper and Bewick’s Swans in Ireland: results of the International Swan Census. January 2010. Irish Birds 9, 1-10. Lewis, L.J. & Tierney, T.D. (2014) Low tide waterbird surveys: survey methods & guidance notes. Irish Wildlife Manuals, No. 80. National Parks and Wildlife Service, Department of Arts, Heritage and the Gaeltacht, Ireland. Lewis, L.J., Burke, B. & Crowe, O. (2016). Review and Assessment of Waterbird Data from the Shannon-Fergus Estuary. BirdWatch Ireland, Kilcoole, Wicklow, Ireland. NPWS. (2012) Conservation Objectives Series, River Shannon and River Fergus Estuaries SPA 004077. National Parks and Wildlife Service, Department of Arts, Heritage and the Gaeltacht, Ireland. NPWS. (2012) River Shannon & River Fergus Estuaries Special Protection area (Site Code 4077). Conservation Objectives Supporting Document. National Parks and Wildlife Service, Department of Arts, Heritage and the Gaeltacht, Ireland. Wernham, V.V et al (2002) The Migration Atlas: movements of birds of Britain and Ireland. T & AD Poyser. London.

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