Offshore wind energy - sectoral marine plan: seabird tagging feasibility

How to undertake a seabird tagging study for species and colonies potentially impacted by the sectoral marine plan for offshore wind energy

Tagging Study Timelines

Carrying out an effective tagging study can be logistically challenging. Consequently, careful planning is required to ensure that all tasks are carried out in a timely manner. Sufficient time needs to be allowed for ordering tags, obtaining all necessary licences and permissions, and to safely deploy tags and monitor any potential tag effects. The exact timing of any tag deployment will depend on the species concerned and the attachment method used. However, indicative timelines are set out below (Figure 2).

Figure 2 Gantt chart setting out indicative timelines for a successful tagging study. Black indicates timings in which work must be completed by those leading the tagging study and grey indicates time allowed for equipment delivery and for SMTP (Special Methods Technical Panel) and NatureScot to consider applications for tag deployment, and in the case of NatureScot carry out a Habitats Regulations Assessment to consider the effects of tagging at SPAs.


Tag orders

It is assumed that any tagging will take place during the seabird breeding season (Figure 2). Ideally, any tags should be obtained well in advance of deployment to allow time for testing, calibration and programming. This is particularly important where additional behavioural data are required from the tags, besides location information (e. g. flight heights and speeds, diving behaviour). Prior to placing tag orders, there should be informed discussions with project funders in relation to the trade-offs between battery life and the types of data that can be recorded (e.g. complete tracks vs high temporal resolution positional data). This will help to ensure that the objectives of any study are clear and the funders are aware of the capabilities of the tags chosen for the work.

At present, a key constraint is a global shortage of microchips following the disruption in supply chains caused the COVID-19 global pandemic. Tag manufacturers need to order microchips well in advance of constructing and delivering tags, which can contribute to long lead times on tag delivery. Discussions with a number of manufacturers (Ornitela, Lotek, Ecotone, and Migrate Technology) suggest that 12 weeks is a typical delivery time for tags. However, all companies indicated that February-May is their busiest period, and that longer lead times may be required for larger orders. Consequently, they advised that late January should be seen as a deadline for placing orders, and that for large orders (>80 tags), as early as the beginning of December would be advisable. If necessary (e.g. to allow time for some testing and programming) rolling delivery is possible with smaller batches of tags delivered as they become available. It should be noted that, as bespoke devices, these tags can have a limited shelf life and tag maintenance (e.g. ensuring batteries are charged) over a full year can be a very time-consuming task. Consequently, placing a bulk order with a view to having devices to deploy in subsequent years is not advised. It should also be noted that orders placed with companies outside the UK may be subject to import duties and have extended delivery times.

Landowner Permission

Permits to catch and ring birds in the United Kingdom are issued by the British Trust for Ornithology. However, these permits do not infer any right of entry onto land without the landowner’s permission. Consequently, where necessary, permission to catch birds and deploy tags should always be sought prior to the start of any fieldwork. It is strongly advised that the owners of any land on which tagging work will take place are identified at an early stage (e. g. around the same time as tag orders and licensing) and approached to obtain permission for the proposed fieldwork. Developing a constructive relationship with any landowners will help with the successful delivery of any project, and feedback on the key findings from any work (e.g. maps of seabird tracks) is usually highly appreciated.

NatureScot Permission

Permission to deploy tags within an SPA must be obtained from NatureScot (or the appropriate Statutory Nature Conservation Body if elsewhere in the UK) prior to any fieldwork taking place. This permission should be sought by contacting The application should include sufficient information to enable NatureScot advisors to complete a robust assessment, including formal HRA record, of both the application itself, and any potential in-combination effects with other proposed work. This should include:

  1. Full contact details of the individual who will be the licence holder; including full name, address (work or home), email address and telephone number.
  2. If this is their first licence application for bird research, NatureScot require two references familiar with their work in this area and be able to vouch for their competence.
  3. A short summary of the purpose of the proposed work and justification for why the research is necessary.
  4. Details of the proposed activity requiring a licence, including species, numbers of individuals targeted, life stage and actions (e.g. disturb or take).
  5. Details of alternatives to the proposed licensable activities in order to carry out the research that have been tried or considered, with an explanation of why these alternatives are not suitable.
  6. Which months (inclusive) of the year is the work planned for? Provide start and finish dates if known.
  7. Details of how many days will be spent in the field undertaking the work, how long is anticipated being on site each day and how long processing birds will take (if applicable). A worst and best case scenario is helpful for NatureScot to assess potential disturbance risk.
  8. Location(s) proposed to undertake the work. The more details provided on this, the more specific NatureScot can be in their advice. Maps and locations (including a six-figure grid reference, e.g. NM123456) are helpful, particularly from a National Nature Reserve (NNR) management perspective.
  9. Methods to be used and why.
  10. Details of all researchers involved in the fieldwork, including how many people will be undertaking the work in the field at any one time. This enables NatureScot to assess potential disturbance risk. In addition, please detail the level of experience researchers undertaking the work have. If researchers have limited experience of working in seabird colonies/using the methods proposed, please provide details on how they will be supported/assisted.
  11. What mitigation has been incorporated in the methods/experimental design to minimise potential risk of injury, mortality and disturbance of target and non-target species? Consideration should be given to potential risks to species at the target field site and also on transit to the target field site.
  12. Details of the monitoring plan (of both target and non-target species) to ensure mitigation is proving effective and your research activities are not having a negative effect. Include how potential negative effects will be detected, and if detected, what actions will be taken. All negative impacts are required to be reported immediately to NNR staff (if the study location is within an NNR).
  13. Any evidence underpinning the licence application, including reports, peer-reviewed scientific papers, etc.
  14. Licence references for any previous and/or associated licence applications connected with the work.

For full details and any updates see NatureScot's Seabird Research Licence Applications

NatureScot currently advise allowing a minimum of three months for them to consider any applications, though contact at the earliest opportunity is preferable. Consequently, it is suggested that applications are submitted by mid-January at the latest for summer tagging work.

In addition to obtaining permission to work in an SPA, it is important to consider whether any schedule 1 species (e.g. Peregrine Falcon) may be disturbed by the proposed work, irrespective of whether or not the species is a feature of the SPA. Consequently, it is recommended that researchers contact local raptor study groups to determine whether there are any birds in the area that may be disturbed and, if necessary, apply for a schedule 1 licence.

Special Methods Technical Panel Permission

Any project involving the marking and/or fitting of any device other than a standard BTO metal ring, or the use of a non-conventional trap, as defined by the Ringers’ Manual (Redfern & Clark, 2001) requires permission as a special method from the Special Methods Technical Panel (SMTP). There are currently 45 defined Special Methods which have been assigned to a ‘Low’, ‘Medium’, ‘High’ or ‘Very High’ risk category through discussion with the Home Office:

  • Low risk (e.g. colour marks and feather clipping) – considered by the BTO Licensing Officer.
  • Medium risk (e.g. swabbing, plucking feathers) – considered by the BTO Licensing Officer.
  • High risk (e.g. wing tags, glued/taped devices, ring/flag/collar mounted devices, leg-mounted devices) – considered by Special Methods Technical Panel (SMTP) unless a similar project has already been approved, in which case approved by the BTO Licensing Officer.
  • Very High risk (e.g. necklaces, harness-mounted devices) – considered by SMTP.

Initially, all applications are made to the BTO licensing officer, who then forwards these on to the Special Methods Technical Panel (SMTP) as appropriate. All applicants are asked to complete a detailed form highlighting:

1. project aims

2. location

3. people involved in all aspects of fieldwork and their relevant experience, including ringing permit details

4. proposed sample size for each combination of species, sex and age

5. the technical detail of the Special Method to be employed.

Where projects are considered by SMTP, they need to be supported by at least two members of the SMTP, plus the Chair of the SMTP, for approval to be granted. For higher risk and/or novel methods, the process may be discursive, with SMTP requesting further information from the applicant and, if required, steering them towards more appropriate alternative techniques.

Approval is only granted on condition that applicants have been suitably trained. Ideally, this training would be face to face with an experienced trainer, but for low-risk methods passive training is acceptable. However, for medium and high risk methods one-to-one field training from an experienced practitioner, and a reference from that practitioner is required as part of the application.

The outcome of the application will be communicated to the applicant by the BTO licensing officer. This will include details of any modifications to the proposed protocol and any reporting conditions. A report meeting the conditions set out in this permission must be submitted by the end of the licensing year in which the activity was completed. Requests for any renewal of the permissions for subsequent years is made at this stage.

For more information, please see the BTO’s guidance on licencing and sampling methods.

Due to the discursive nature of the process, it is recommended that at least three months are allowed for applications, and that these are submitted by the end of January for summer tagging work.


The logistics involved in planning and successfully delivering a tagging project should not be under-estimated. Noting that fieldwork may take place in a remote location, during peak holiday season, accommodation should be booked at an early stage. Ideally, this accommodation should be close (e.g. within 30 minutes’ drive) to the field site, with sufficient parking for all project vehicles, and space for staff to relax at the end of a busy day in the field and somewhere suitable for storing all field equipment. Given the unpredictable nature of fieldwork, flexibility in timing is crucial. Consequently, holiday cottages, which can be let for 1-2 months (covering both tag deployment and monitoring for any tag effects), often make excellent options for accommodation during the field season.

At an early stage in the planning process, the availability of field staff, and contingency staff should be confirmed. A pre-season meeting should be held to outline plans for the field season. The status of ringing permits and any additional training needs (e.g. rope access, first aid training) should be discussed. Any personal field equipment needs including Personal Protective Equipment (e.g. suitable clothing and footwear, eye protection, gloves, etc) should also be identified. Risk assessments should be prepared and completed, and all field protocols should be checked to ensure that they are compliant with COVID and Highly pathogenic avian influenza (HPAI) requirements. These assessments should be kept under review in the event of circumstances changing closer to the field season.

An equipment inventory should be completed. This should cover all field equipment including ringing kit, harness material and optics (e.g. binoculars and/or telescopes) to be used for monitoring, as well as a first aid kit. Any additional equipment required should be ordered at as early a stage as possible. This should include ensuring that there is a backup phone for use in the field (e.g. in case batteries run out), and mobile internet dongle (if using base station to download data over the internet). Mobile phone coverage should be checked prior to the start of any fieldwork, and, in situations where coverage is very limited, or non-existent, alternative options should be considered to ensure the safety of field workers. Any need for lone working (e.g. during post-deployment monitoring visits) should be identified at this stage and appropriate protocols should be agreed and put in place.

At least one and, ideally two or three, recce visits should be undertaken. The first visit should be undertaken early on in the project to assess potential ringing sites, identify any access issues and consider possible locations for base stations (devices placed in the vicinity of the colony through which tag data are remotely downloaded). The second visit should take place once the breeding season is underway, with a third visit to help identify median laying dates particularly valuable for guillemots and razorbills due to their short chick-rearing period, compared to other seabirds. The aims of this visit should be to assess the status of the breeding season, with a view to identifying the optimal timing for deploying tags, and to identify a sample of nests to target for deploying tags. Ideally, tags should have been delivered by the time of this second recce visit. Assuming this is the case, these should be carried during the visit in order to check functionality, and if possible, to inform the deployment of the base stations, e.g. ensuring the base station can pick up a signal from the tag when the tagged bird is at the nest.

It is also important to engage with local stakeholders, including ringers and ringing groups, at an early stage. This serves two purposes. Firstly, these stakeholders are likely to have valuable local knowledge about sites that may be suitable for catching and tagging birds. Related to this, they may also be able to facilitate contact with local landowners, and make suggestions for locations in which equipment such as base stations could be deployed. Secondly, where a local ringing group has an existing ringing and colour-ringing scheme, these schemes should be used in preference to setting up a new project associated with the tagging work. Note though, that any rings used should be paid for as part of the tagging work. Where local ringing groups, or others, provide support to the project, an honorarium should be considered. If any volunteers assist with the tagging, they should be asked to complete risk assessments.

Immediately prior to deployment, the duty cycles and settings for the tags should be finalised and programmed. Fieldwork information sheets (key contacts, site information, medical details) and data collection sheets (e.g. for ringing details and tag settings) should be printed, and care should be taken to ensure suitable vehicles are available for the fieldwork. In the case of a multi-colony study, involving multiple research institutes, ideally a shared field protocol would be agreed in advance in order to maximise the value of any data collected, particularly in relation to the monitoring of device effects.


Ahead of the tag deployment, a final briefing should be held for all field staff. Key expectations should be set out, and all staff should be clear about their roles and responsibilities in the field and Health & Safety requirements. During tagging sessions, all COVID and HPAI requirements should be followed, including cleaning and disinfecting kit when moving between sites to minimise the risk of HPAI transmission. If time and the project allow, training in the fitting of tags to birds may be offered to suitably experienced personnel by licence holders, with a view to increasing capacity for future tagging studies. Though note that any potential training, or increase in the number of people involved in the fieldwork, should be flagged to NatureScot as part of the application process in mid-January, to enable an accurate assessment of the potential for disturbance to be made. At the end of each tagging session, field backups of data sheets should be collected prior to leaving the site (e.g. through digital photographs of each data sheet). Where possible (e.g. for remote download GPS tags), as tags are deployed, the data obtained should be checked to ensure the tag is delivering as expected, and updates should be offered to project funders, and other interested stakeholders (if appropriate).

Following tag deployment, licence conditions for monitoring of possible tag effects should be followed. Monitoring requirements can be aided through annotated digital photographs which clearly identify the locations of any tagged and control nests. Should this monitoring involve any periods of lone fieldwork, lone fieldworker protocols must be put in place and followed.

Post-Field season

Following the completion of the field season, all data collected should be cleaned and backed up. The field kit should be sorted, cleaned and stored, with any broken or missing items noted, and replaced or repaired as required. Where data collection will continue over winter, and settings can be altered remotely, settings should be adjusted to facilitate prolonged data collection whilst preserving battery life.

All of the ringing data should be submitted to the BTO using the Demography Online (DemOn) portal[4], and any resighting and/or nest monitoring data should be analysed in preparation for the SMTP Reports, which must be submitted by the end of the licensing year in which the work was carried out. Feedback should be provided to funders (and other stakeholders, as appropriate) detailing the outcomes from the fieldwork. Where archival loggers (e.g. geolocators) have been deployed over winter, plans should be made to retrieve these the following breeding season.



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