FAD Buoy Data Format

Fish Aggregating Device (FAD) buoy data encompasses two categories of information collected by electronic buoys deployed at sea by purse seine fishing vessels: positional data (GPS fixes transmitted at regular intervals) and echosounding data (acoustic biomass estimates of fish aggregations beneath the buoy).

FAD buoy data are submitted by buoy technology providers on behalf of fishing companies, in compliance with ISSF Conservation Measure 3.7 and the reporting obligations of tuna Regional Fisheries Management Organisations (RFMOs). Data are used by SPC–OFP for FAD monitoring, stock assessment inputs, and ecosystem studies.

Each record in a position file represents a single GPS transmission from a buoy. Each record in an echosounding file represents a single acoustic reading, linked to a position record via a unique transmission identifier. The combined format — where position and echosounding data are provided in a single file — is the preferred submission format, as it directly associates each acoustic reading with its corresponding GPS fix.

Submissions must cover data from within the WCPFC Convention Area. Where FADs drift across the WCPFC–IATTC overlap zone, data may be shared with IATTC in accordance with inter-RFMO agreements.

ISSF Guidelines Reminder

Submission of FAD buoy data is governed by ISSF Conservation Measure 3.7 (Transactions with Vessels or Companies with Vessel-Based FAD Management Policies). The relevant requirements are:

• Purse seine vessels and supply vessels covered by a FAD Management Policy must report FAD position data to the relevant RFMO science bodies and/or national scientific institutions and/or their flag State.
• Reporting must occur with a maximum time lag of 90 days.
• Where data are reported to national institutions, those institutions must make the data available to the relevant RFMO for scientific purposes.

ISSF minimum required data fields:

• Buoy ID
• Fishing Company
• Vessel Name / Vessel IMO Number
• Date
• Time
• Latitude
• Longitude

The SPC–OFP standard described in this document is fully consistent with and extends these minimum requirements.

Submission schedule (recommended):

Data for each calendar month should be submitted as a complete file before the 90-day deadline.

Field Formatting Details

• All datetime fields must be in ISO 8601 format: YYYY-MM-DD HH:MM:SS, expressed in UTC. Local times are not accepted.
• Coordinates must be in signed decimal degrees: negative values for South latitudes and West longitudes (e.g. -10.2345 for 10.2345°S). A minimum of 2 decimal places is required; 4 decimal places is strongly recommended for scientific usability.
• Coordinates are mandatory and must never be blank. Records without a valid GPS fix should not be submitted.
• The transmission_id field must be unique within a submission file. It serves as the primary key linking position records to echosounding records when data are submitted in two separate files. If no natural unique identifier exists in the source system, providers should generate a synthetic key (e.g. {buoy_id}_{transmission_datetime} with special characters removed).
• Echosounding values (sounder_values) must be provided as a dash-separated string of numeric values, one per depth layer (e.g. 0-0-3-5-12-8-0-0). The depth covered by each layer is defined by start_depth_m and sounder_depth_interval_m. The total depth range is implicit from the number of values in the string.
• buoy_provider must use the two-letter codes defined in Reference Table 1. For providers not yet listed, contact SPC–OFP to request addition to the reference table before submission.
• sounder_unit must use the codes defined in Reference Table 2.
• File format: CSV (.csv) or Excel (.xlsx) are accepted. UTF-8 encoding is required for CSV files.
• File naming convention: FAD_{buoy_provider}_{vessel_imo}_{YYYYMM}.csv (or .xlsx). Example: FAD_SL_1024172_202508.csv.
• Submission channel: files must be sent to ofp.fad.data@spc.int.
• Submission frequency: monthly, one file per vessel per month, covering the complete calendar month.

Document Structure and Data Fields Format

FAD buoy data may be submitted in one of three formats:

• Combined format (preferred): positions and echosounding data in a single file. Each row contains a position fix and, where available, an associated echosounding reading. Rows with no echosounding data leave the sounder fields blank.
• Positions-only format: a file containing only GPS position records. Must be paired with a separate echosounding file using transmission_id as the linking key.
• Echosounding-only format: a file containing only acoustic readings, each referencing a position record via transmission_id.

CSV Data Templates

• Combined Template — Positions + Echosounding
• Positions-only Template
• Echosounding-only Template

Combined Format (Preferred)

This is the recommended submission format. Each row represents one position transmission. Echosounding fields are populated where an acoustic reading is associated with that transmission; they are left blank where no echosounding data exists for that position fix.

Example — Combined format

Field descriptions — Combined format

Positions-only Format

Used when positions and echosounding data are submitted in two separate files. Each row represents one GPS transmission. The transmission_id field is mandatory and must match corresponding records in the echosounding file.

Example — Positions-only

Field descriptions for the positions-only format are identical to the position-related fields in the combined format table above.

Echosounding-only Format

Used when submitted separately from position data. Each row represents one acoustic reading. The transmission_id must match a record in the corresponding positions file. Where an exact transmission_id match is not possible (e.g. because the sounder fires on a different schedule than the GPS), provide buoy_id and sounder_datetime — SPC will perform a nearest-position match at ingestion.

Example — Echosounding-only

Field descriptions — Echosounding-only

References

Reference Table 1 — Buoy Provider Codes

This list is maintained by SPC–OFP. Providers not listed should contact ofp.fad.data@spc.int to request addition before submitting data.

Reference Table 2 — Sounder Unit Codes