About

Christopher Costello is the Research Director of the Environmental Markets Lab (emLab) and Co-Director of emLab's Ocean & Fisheries Program. He is also a Professor of Resource Economics at the Bren School. His research centers on natural resource economics, incomplete property rights, and decision making under uncertainty, with a particular focus on the value and effect of information on management decisions. Costello combines theoretical microeconomics with modeling and empirical analysis to inform policy on fisheries management, biological diversity, introduced species, industrial regulation, and marine policy. He has collaborated closely with national governments, international organizations, NGOs, and other partners worldwide to translate his research into practical actions across a diverse range of developed and developing countries. Currently, he serves as an advisor to California’s Governor Newsom on the Council of Economic Advisors and as a trustee of the Environmental Defense Fund and The Nature Conservancy (California). Christopher Costello holds a Ph.D. in Agricultural and Resource Economics from the University of California, Berkeley. Outside of his professional work, he enjoys hobbies such as cycling, gardening, woodworking, blacksmithing, beekeeping, and spending time with his family.

Research topics

• Fishery
• Biology
• Business
• Computer Science
• Environmental science
• Ecology
• Geography
• Political Science
• Sociology
• Computer Security
• Environmental resource management
• Law
• Telecommunications
• Economics
• Natural resource economics
• Agricultural economics

Selected publications

• Charting a science course for the sustainable transformation of aquatic food systems

  ICES Journal of Marine Science · 2025-01-01 · 3 citations

  articleOpen access

  Abstract Aquatic foods hold a unique potential to contribute to a much-needed transformation of food systems thanks to their high nutritional value, cultural significance, and relatively low environmental impact. However, realizing this potential requires a transformative approach to help overcome two grand challenges: sustainably increasing the production of nutritious aquatic foods and ensuring equitable access to these resources. This paper highlights the key recommendations from the White Paper on Challenge 3 (‘Sustainably nourish the global population’) of the United Nations Decade of Ocean Science for Sustainable Development (hereafter, the Ocean Decade), developed by a group of experts under the Vision 2030 process, on the science needed to support a ‘Blue Transformation’. A holistic, interdisciplinary science agenda is proposed, emphasizing strengthened institutional and public–private partnerships, prioritizing the inclusion of small-scale actors, women, and youth, and focusing on delivering science targeted to solve specific challenges. The Ocean Decade provides a platform to catalyse these efforts, fostering a paradigm shift towards inclusive, co-created science. Achieving these goals will enable aquatic food systems to contribute significantly to global food security and the Sustainable Development Goals by 2030.

  PublisherOA PDFDOI

• Global Expansion of Marine Protected Areas and the Redistribution of Fishing Effort

  Washington, DC: World Bank eBooks · 2025-01-10

  bookOpen access

  The expansion of marine protected areas (MPAs) is a core focus of global conservation efforts, with the “30x30” initiative to protect 30% of the ocean by 2030 serving as a prominent example of this trend. This paper examines a series of proposed MPA network expansions of various sizes and forecasts the impact that increased protection could have on global patterns of fishing effort. This is accomplished using a predictive machine learning model trained on a global dataset of satellite-based fishing vessel monitoring data, current MPA locations, and spatiotemporal environmental, geographic, political, and economic features. The model predicts future fishing effort under various MPA expansion scenarios, compared to a business-as-usual counterfactual scenario that includes no new MPAs. The difference between these scenarios represents the predicted change in fishing effort resulting from MPA expansion. The results show that, regardless of the MPA network's objective or size, fishing effort would decrease inside the MPAs, though by much less than 100%. Moreover, this reduction in fishing effort within MPAs does not simply shift outside—fishing effort outside MPAs also declines. The overall magnitude of the predicted decrease in global fishing effort principally depends on where networks are placed in relation to existing fishing effort. MPA expansion will lead to a global redistribution of fishing effort, which should be considered in network design, implementation, and impact evaluation.

  PublisherOA PDFDOI

• Bilateral marine reserve agreements

  Theoretical Ecology · 2025-03-19

  articleOpen accessSenior author

  Abstract We examine whether the mobility of a transboundary stock can incentivize a bilateral marine reserve agreement, where one fishing country pays its neighbor to become a marine reserve. The key insight is that precisely because fish move across borders, non-cooperative extraction is likely to be excessive, which lowers fishery profits for both countries. Under our proposal, the payor benefits from the spillover and elimination of non-cooperative extraction, both of which raise fishing profits. The payee benefits from direct financial compensation in exchange for creating the marine reserve. We create a dynamic and spatial game between two countries sharing a transboundary stock. We determine the mobility conditions under which the payor is willing to pay and the payee is willing to accept the payment. We illuminate the biological and economic conditions under which an agreement is incentive-compatible for both countries and conditions under which one or both countries would oppose such an agreement. We find that larval dispersal plays little role in agreement acceptance if adult movement is high. However, if adult movement is low, high larval dispersal can promote agreement acceptance. We also find that this agreement can fully reproduce the conservation and economic benefits gained under a cooperative fishing agreement if adult movement from the fishing patch to the reserve patch is low (≤ 40%) and adult movement to the fishing patch is high (≥ 60%). We discuss the implementation challenges using four real-world transboundary stocks and highlight global issues that bilateral marine reserve agreements can help solve.

  PublisherOA PDFDOI

• Little-to-no industrial fishing occurs in fully and highly protected marine areas

  Science · 2025-07-24 · 8 citations

  article

  There is a widespread perception that illegal fishing is common in marine protected areas (MPAs) due to strong incentives for poaching and the high cost of monitoring and enforcement. Using artificial intelligence and satellite-based Earth observations, we provide estimates of industrial fishing activity in fully and highly protected MPAs worldwide, in which such fishing is banned. We find little to no activity in most cases. On average, these MPAs had just one fishing vessel present per 20,000 square kilometers during the satellite overpass, a density nine times lower than that of the unprotected waters of exclusive economic zones.

  PublisherDOI

• The shadow cost of mobile public bads

  Journal of Environmental Economics and Management · 2024-06-05 · 1 citations

  articleSenior author
  PublisherDOI

• Sharing and expanding the co-benefits of conservation

  Ecological Economics · 2024-01-21 · 9 citations

  article
  PublisherDOI

• Global expansion of marine protected areas and the redistribution of fishing effort

  Proceedings of the National Academy of Sciences · 2024-07-09 · 25 citations

  articleOpen access

  The expansion of marine protected areas (MPAs) is a core focus of global conservation efforts, with the "30x30" initiative to protect 30% of the ocean by 2030 serving as a prominent example of this trend. We consider a series of proposed MPA network expansions of various sizes, and we forecast the impact this increase in protection would have on global patterns of fishing effort. We do so by building a predictive machine learning model trained on a global dataset of satellite-based fishing vessel monitoring data, current MPA locations, and spatiotemporal environmental, geographic, political, and economic features. We then use this model to predict future fishing effort under various MPA expansion scenarios compared to a business-as-usual counterfactual scenario that includes no new MPAs. The difference between these scenarios represents the predicted change in fishing effort associated with MPA expansion. We find that regardless of the MPA network objectives or size, fishing effort would decrease inside the MPAs, though by much less than 100%. Moreover, we find that the reduction in fishing effort inside MPAs does not simply redistribute outside-rather, fishing effort outside MPAs would also decline. The overall magnitude of the predicted decrease in global fishing effort principally depends on where networks are placed in relation to existing fishing effort. MPA expansion will lead to a global redistribution of fishing effort that should be accounted for in network design, implementation, and impact evaluation.

  PublisherDOI

• A market for 30x30 in the ocean

  Science · 2024-06-13 · 8 citations

  article

  Marine protections could benefit from trade in obligations.

  PublisherDOI

• Credit Markets, Property Rights, and the Commons

  Journal of Political Economy · 2024-02-06 · 8 citations

  articleSenior author

  Credit markets and property rights are fundamental for modern economies, but their implications for the commons are unknown. Using a dynamic model of competitive resource extraction, we show that improving property right security unambiguously increases conservation incentives, but the effect of credit markets on resource extraction effort hinges on the security of property rights. We test these predictions using data on global fisheries, credit markets, and the largest ever marine property rights assignment. We find that property right security reduces resource extraction and that credit market development increases resource extraction under insecure property rights but reduces resource extraction under secure property rights.

  PublisherDOI

• Enhancing global food security through the introduction of Maximum Sustainable Yield targets in fisheries

  Research Square · 2023-12-14 · 1 citations

  preprintOpen access
  PublisherOA PDFDOI

Frequent coauthors

• Nicolas Quérou

  Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement

  93 shared

• Agnès Tomini

  78 shared

• Steven D. Gaines

  University of California, Santa Barbara

  44 shared

• Matthew J. Kotchen

  Yale University

  24 shared

• Benjamin S. Halpern

  University of California, Santa Barbara

  21 shared

• Olivier Deschênes

  University of California, Santa Barbara

  17 shared

• Dominic P. Parker

  University of Wisconsin–Madison

  17 shared

• Stephen Polasky

  University of Minnesota

  16 shared

Labs

• emLabPI

  Natural resource economics, incomplete property rights, decision making under uncertainty

Awards & honors

• Bren Researchers Named to 2020 Highly Cited List