Bycatch of unwanted fish species
Measurement answer
What this metric measures
Reports unwanted bycatch of non-target fish species by scientific name, including its quantity, proportion of total catch, and the quantity and proportion retained for sale.
Specification
Metric specification
- Result format
- Structured table
- Unit
- tonnes or count; percentage (%) — source-defined reporting unit
- Reporting basis
- Reporting period
- Aggregation
- Reported by non-target fish species identified by scientific name; retain weight or count and related proportions separately rather than aggregating across species.
- Pillar
- Environmental
- Topic
- Bycatch and fisheries impacts on species
- Controlled domain
- Nature, biodiversity and land
- Entity type
- Metric
Reporting boundary
Bycatch arising from the reporting organization's fishing, fish trading, fish processing and retail activities, as applicable.
Verified source occurrences
Framework coverage
This is one canonical metric. The bindings below show every verified framework occurrence without creating duplicate metric pages. Edition, disclosure, role, and relationship remain source-specific.
- Adopting DisclosureSource evidence
TNFD sector guidance
- Publisher
- Taskforce on Nature-related Financial Disclosures
- Edition
- Final English sector guidance collection through August 2026 (17 documents)
- Requirement
- Not Specified
- Relationship
- Defines Disclosure
- Mapping outcome
- Direct Evidence
- Source locator
- TNFD Fishing sector guidance, Section 3.2, Table 16, metric F.C3.0, p.84 | p.84, Section 3.2, Table 16, F.C3.0
- Adopting DisclosureF.C3.0
TNFD sector guidance
- Publisher
- Taskforce on Nature-related Financial Disclosures
- Edition
- Version 1.0, June 2025
- Requirement
- Conditional
- Relationship
- Maps Source Identity
- Mapping outcome
- Published
- Source locator
- p.84, Section 3.2, Table 16, F.C3.0
Value structure
Dimensions and units
- Unit
- tonnes or count; percentage (%) — source-defined reporting unit
- Reporting basis
- Reporting period
Unit meaning: Values use tonnes or count; percentage (%) under the disclosed TNFD sector-guidance method, reporting period and boundary.
Table fields and units
- Non-target fish species scientific name
- Measurement basis
- Bycatch weight or count
- Total catch
- Bycatch as proportion of total catch
- Bycatch retained for sale weight
- Bycatch retained for sale as proportion of bycatch
- Applicable activity
Published dimensions
- Non-target fish species scientific name
- Measure basis: weight or count
- Total catch
- Proportion of total catch
- Bycatch retained for sale
- Weight and proportion of retained bycatch
- Applicable activity: fishing, fish trading, fish processing or retail
Disclosure method
Formula information
- Status
- Not applicable
- Formula type
- Structured Disclosure
Disclosure form
No single formulaReport the source-defined result with its stated fields and method disclosures. F.C3.0 specifies a reportable, species-level outcome table with explicit quantities and proportions. It is not the same construct as affected-species population, extinction-risk, or invasive-species metrics because it measures catch composition and retained bycatch.
Verified sources
Evidence and status sources
Sustopedia checked each record-specific claim directly against primary publisher material. Labels distinguish current measurement authority from future compatibility and corroborative, legal, edition, or method status context. Corroborative evidence can support a stated limitation but cannot establish the core measurement by itself.
Measurement evidence
- Measurement evidenceChecked 30 August 2026
TNFD additional sector guidance collection
- Publisher
- Taskforce on Nature-related Financial Disclosures
- Edition
- Final English sector guidance collection through August 2026 (17 documents)
- Locator
- TNFD Fishing sector guidance, Section 3.2, Table 16, metric F.C3.0, p.84 | p.84, Section 3.2, Table 16, F.C3.0
Supports: The official TNFD sector guidance supports the identity, boundary and method basis of “Bycatch of unwanted fish species”.
Open official source
Use with context
Interpretation boundaries
Method disclosures required
Source-edition basis: TNFD sector guidance, Final English sector guidance collection through August 2026 (17 documents).
- Disclose the scientific name used to identify each non-target fish species.
- Disclose whether each quantity is reported by weight or count.
- Disclose the total-catch basis used for each proportion.
- Disclose the basis used to identify bycatch retained for sale and report its weight and proportion separately.
- Disclose which of fishing, fish trading, fish processing and retail activities are included.
Record-specific limitations
- The metric is limited to unwanted non-target fish species and does not constitute a complete account of all catch impacts.
- Weight and count are alternative measurement bases and should not be combined without an explicit conversion method.
- Proportions depend on the stated total-catch denominator and the treatment of retained bycatch.
Interpret this metric with the stated reporting boundary, period convention, value shape, and unit. Results prepared with different boundaries or conventions may not be directly comparable.
Measurement evidence supports the core record-specific claims described above. Corroborative evidence can support limitations, while compatibility and status sources provide their separately labelled context. None of these cards by itself determines an organisation's legal applicability, filing readiness, assurance status, or compliance conclusion.