Title Competing Hypotheses and Scientific Non-Recognition: Investigating the Hector’s and Māui Dolphin Decline in the Context of Wartime Chemical Legacies
Author(s) Gibbs Andrew, Dmitry Nikolaenko
Affiliation Independent researcher
Editor-in-Chief of Pollution and Diseases
Country New ZealandRSA
Contribution type discussion contribution
Thematic area • Theory, Methodology, and Evidence• War and Health
Conference framework connection • Analytical Track AT-01 — provisional title to be defined• Analytical Track AT-02 — provisional title to be defined• Analytical Track AT-03 — provisional title to be defined• Analytical Track AT-04 — provisional title to be defined• Analytical Track AT-05 — provisional title to be defined• Analytical Track AT-06 — provisional title to be defined• Analytical Track AT-07 — provisional title to be defined
Abstract This e-poster examines the decline of Hector’s and Māui dolphins in New Zealand as a case of fragmented ecological knowledge and competing causal explanations. The poster does not claim that the decline was caused by herbicide-related contamination. Instead, it asks how competing hypotheses should be evaluated when available evidence is incomplete, unevenly distributed, and institutionally sensitive.
The dominant explanation for the decline has focused on fishing-related mortality, including bycatch and net entanglement. This explanation is important and must remain part of the analysis. However, it may not fully address all unresolved questions concerning population scale, reproductive decline, contaminant findings, and historical industrial sources. A second hypothesis concerns possible exposure to organochlorine contaminants, including dioxins, furans, PCBs, DDT-related compounds, and chemical residues associated with chlorinated herbicides and the wider wartime herbicide production economy of the Vietnam War era.
The methodological problem is not simply that the contamination hypothesis is unproven. Rather, the problem is that different hypotheses may be treated unequally under conditions of incomplete evidence. Some explanations become institutionally acceptable, while others are classified as speculative before they are systematically tested. Drawing on the concept of regimes of scientific recognition, this poster examines how evidence is selected, connected, excluded, or downgraded when a hypothesis is politically, institutionally, or scientifically inconvenient.
The poster proposes a comparative hypothesis framework. It distinguishes between source evidence, pathway evidence, exposure evidence, tissue-burden evidence, biological-effect evidence, population-level evidence, and causal evidence. The framework compares fishing, demographic fragility, habitat and food-web change, and contamination-related hypotheses according to what each explains, what each fails to explain, what evidence is missing, and what institutional assumptions shape its acceptance or rejection.
The contribution is methodological. The aim is not to replace one insufficiently proven explanation with another, but to create a fair procedure for testing competing hypotheses under conditions of fragmented evidence. The Hector’s and Māui dolphin case shows why war-related pollution research must examine not only contamination itself, but also the scientific and institutional processes through which some forms of harm become recognizable while others remain outside accepted explanatory regimes.
Key points ● The Hector’s and Māui dolphin decline should be approached as a case of competing hypotheses and fragmented ecological knowledge, not as a closed causal question.● Fishing-related mortality, demographic fragility, habitat change, and contamination-related explanations should be compared through the same evidentiary standards.● The hypothesis concerning dioxins, furans, chlorinated herbicides, and Vietnam War-era chemical production legacies should not be accepted without evidence, but it also should not be dismissed before systematic testing.● The central methodological issue is unequal recognition: some hypotheses become institutionally acceptable while others remain marginal because they are inconvenient to established scientific and policy frameworks.● A fair research framework must distinguish source, pathway, exposure, tissue-burden, biological-effect, population-level, and causal evidence.
Keywords Hector’s dolphin; Māui dolphin; scientific recognition; fragmented evidence; competing hypotheses; dioxins; furans; chlorinated herbicides; Vietnam War; war-related pollution; ecological decline; environmental uncertainty; hypothesis verification
Main discussion question How can scientific systems prevent politically or institutionally inconvenient hypotheses from being dismissed before they are properly tested under the same evidentiary standards as dominant explanations?
OJS publication link https://pollution-diseases-ojs.org/index.php/pd/article/view/29
Note. Analytical TracksIn addition to the main thematic areas, the conference programme will include several cross-cutting analytical tracks. These tracks will be defined during the preparation of the programme, based on the submitted abstracts and the emerging links between presentations.At the preliminary stage, abstracts may be assigned to provisional analytical tracks marked as AT-01 to AT-07. Final track titles will be announced after the Scientific Committee has reviewed the submitted materials.