From Incident Records to Conservation Intelligence: A Methodological Assessment of Dolphin Mortality Accounting in Aotearoa New Zealand
DOI:
https://doi.org/10.66659/d03rhq84Keywords:
Hector’s dolphin; Māui dolphin; mortality surveillance; strandings; bycatch; necropsy; NZTCS; conservation monitoring; data provenance; adaptive man-agement.Abstract
Aotearoa New Zealand has developed a conservation architecture for Hector’s and Māui dolphins, including statutory reporting, public incident records, necropsy and genetic programmes, fisheries monitoring, abundance surveys, and threat assessments. This paper asks whether that architecture generates mortality information with sufficient completeness, traceability, causal resolution, and correctability to evaluate conservation performance and revise management when evidence changes. We combine an assessment of monitoring with documentary analysis of the New Zealand Threat Classification System (NZTCS), the 2021 research strategy, incident and fisheries materials, an audit of the public incident spreadsheet, and an examination of disputed historical records.
The audit shows improved source retention but persistent limitations. Among mortality records from 2017–2024, 64.3% of linked locations were estimated, 62.7% had a complete necropsy, and 31.0% retained an unresolved cause. Historical records showed provenance gaps, while the public export contained duplicates and candidate legacy discrepancies that cannot be resolved without original sources and a visible correction history. Fisheries verification has improved through cameras, but current metrics cannot represent total mortality. NZTCS provides standardised extinction-risk classification, yet it is neither a mortality audit nor a causal synthesis and can describe chronic crisis as “no change.”
The system is neither inactive nor wholly ineffective, but public evidence does not show that all reasonably available analytical measures are used. A separate national dolphin mortality-intelligence framework is needed to estimate unseen mortality, preserve provenance, reconcile data, compare causal hypotheses, publish corrections, and link monitoring to management evaluation.
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