Laurenne Schiller, PostDoc web

Laurenne Schiller, SPPA Postdoctoral Fellow

SPPA’s Dr. Laurenne Schiller and Professor Graeme Auld, along with co-authors Gregory Britten and Boris Worm use “bright spot” analysis to better understand successful governance of fish populations in their newly published paper  “Learning from positive deviants in fisheries“.

The authors suggest that a positive deviant approach, already used in public health, holds promise for successful fisheries management and protection of overexploited fish populations.

The approach builds a predictive model based on factors normally associated with better stock health. The differences between the model predictions and the performance of stocks are used to identify stocks that perform better – positive deviants – and worse — negative deviants – than expected. Focused analysis of these positive and negative deviants then helps identify new factors that could help improve fisheries management.

Using this approach, the study of Canada identified that commercial species that were doing better than expected – the positive deviants – had lower conflicts among users, balanced involvement of stakeholders in data collection, and better accounting of mortality sources.

Published Feb 5, 2024 in Fish and Fisheries, .


Despite progress in the management of assessed fish populations, many countries lag behind international commitments to restore overexploited stocks to healthy abundances. Here we use a mixed-methods positive deviance approach, also known as ‘bright spot’ analysis, to understand what drives the successful governance of exploited species by learning from positive outliers, or ‘deviants’. We use Canada as a case study, identifying factors driving the abundance of 230 commercially exploited fish and invertebrate populations, of which only 28% were classified at healthy abundance in 2022. We first applied a generalized linear model to test how diverse socio-ecological fishery attributes relate to stock health. We found healthier stocks are positively and significantly correlated with certain management regions, more selective gears, eco-certification, and high fishery value. Counterintuitively, healthier stocks were also associated with high inherent fishing vulnerability and the absence of reference points. We then used fishery expert surveys and interviews to investigate the social and institutional characteristics of stocks healthier than expected, given their circumstances. We found that fisheries targeting these positive outliers have lower conflict among users, balanced stakeholder involvement in data collection and decision-making, and improved accounting of mortality sources. Lessons from these positive deviants can be applied to improve underperforming management systems that are struggling to reverse overexploitation in Canada and elsewhere. More generally, we suggest that a positive deviance approach, already used in public health, could be a promising tool to learn about successful fisheries management interventions, and the diverse actors responsible for ensuring these interventions are successful.

Link to full paper