Seagrass Fisheries Reveal the Hidden Poverty Costs of Marine Conservation

Along the tropical coastlines of the Indo-Pacific, some of the world’s poorest families depend on an ecosystem that most people rarely think about: the seagrass meadows that carpet shallow sandy bottoms between mangrove forests and coral reefs. A new study published in Nature Sustainability draws on data from 156 communities across the region and finds that fishing in seagrass habitats is not a marginal activity but a central economic lifeline, one whose loss would fall hardest on the households least able to absorb it. The research, led by an international team of marine and social scientists, argues that marine conservation policy has systematically overlooked this dependence, with profound implications for how protected areas are designed and how the social costs of ocean protection are counted.

The study’s central contribution is to quantify, at a scale rarely attempted, the relationship between seagrass-associated fishing and household poverty. Survey teams working across community networks in Southeast Asia, Melanesia and the western Indian Ocean gathered household-level data on income, food consumption, fishing effort and habitat use. By combining these social surveys with ecological assessments of seagrass extent and condition, the researchers were able to estimate what share of household income and nutrition flows directly from seagrass fisheries, and how that share varies with household wealth. The answer, they report, is striking: in many communities, seagrass-adjacent fishing contributes a substantial portion of the protein consumed by the poorest quartile of households, far exceeding its contribution to wealthier families in the same villages.

This pattern reflects the particular ecological and economic character of seagrass systems. Unlike offshore fisheries that require boats, fuel and capital, seagrass meadows sit within walking distance of shore, accessible at low tide and by canoe, gleaning and hand-collection. Women, children and landless households — groups often excluded from formal fisheries statistics — harvest fish, octopus, clams, sea cucumbers and other invertebrates from these shallow grounds. Because seagrass fishing requires little investment, it functions as what economists would call a poverty buffer: a low-barrier resource that families fall back on when crops fail, fish prices collapse or formal employment disappears. The new analysis shows that this buffering role intensifies precisely when households are most vulnerable.

The technical core of the study lies in its integration of household survey data with habitat mapping across such a broad geographic range. Rather than studying a single village or country, the team assembled a comparative dataset spanning 156 communities, allowing them to distinguish local idiosyncrasies from regional patterns. They constructed indicators of household poverty that combine income measures with dietary diversity and asset ownership, and then modeled the association between dependence on seagrass-associated fishing and these poverty indicators. Statistical controls for community size, market access, reef and mangrove proximity, and fishing pressure helped isolate the specific contribution of seagrass habitats. The consistency of the signal across dozens of independent communities strengthens the case that the pattern is structural rather than incidental.

Why has this dependence remained so poorly documented? The researchers point to a combination of institutional blind spots. Official fisheries statistics in most countries are designed around landed catches brought to ports and markets, categories that capture trawl and purse-seine activity but miss gleaning and subsistence harvesting. Seagrass meadows, meanwhile, have historically received a fraction of the scientific and philanthropic attention devoted to coral reefs and mangroves, and they remain largely absent from marine protected area networks. Conservation planning in the region has often prioritized biodiversity targets and carbon storage goals without systematic assessment of who depends on which habitats for subsistence. The result is a policy landscape in which an ecosystem supporting millions of the world’s poorest coastal residents is managed, at best, incidentally.

The poverty dimensions of this oversight carry real consequences. When marine protected areas are established around seagrass beds without provision for continued access, or when seagrass meadows are degraded by coastal development, dredging, anchoring and land-based pollution, the resulting losses do not fall evenly across communities. Wealthier households can shift to other incomes, buy protein at markets or relocate fishing effort offshore. Poorer households, the study shows, have fewer alternatives and face immediate nutritional and financial harm. In effect, conservation interventions that appear ecologically neutral can function as regressive shocks, transferring costs from the global benefits of biodiversity protection onto the local poor. The authors frame this as a matter not only of food security but of distributional justice in environmental policy.

The findings also complicate a common conservation narrative in which protecting habitats automatically protects fisheries. Seagrass meadows do support juvenile fish, sequester carbon, stabilize sediments and improve water quality, and safeguarding them is essential to the long-term productivity of tropical coastal waters. But the study emphasizes that habitat protection and livelihood protection are not the same thing. A closed area may allow seagrass biomass to recover while simultaneously cutting off the poorest fishers from the resource, unless access rules, seasonal rotations or alternative livelihoods are built into the design. The researchers argue that conservation effectiveness and social outcomes must be evaluated together, and that the households most dependent on a habitat should be identified before management decisions are made, not after harm has occurred.

Methodologically, the study demonstrates the value of coupling fine-grained social measurement with ecological data across large spatial scales. Poverty is multidimensional, and its relationship to ecosystem use is context-dependent, shaped by tenure arrangements, gender norms, market access and seasonal dynamics. By aggregating standardized surveys across 156 sites, the team produced findings robust enough to inform regional policy while retaining the community-level resolution needed to target interventions. The approach offers a template for other ecosystems — mangroves, floodplains, dry forests — where reliance by poor households is suspected but poorly quantified. In each case, the same question applies: which households lose what when the habitat is degraded or closed, and can any compensatory mechanism realistically reach them?

The policy implications are concrete. The authors call for seagrass ecosystems to be explicitly incorporated into national fisheries assessments, poverty reduction strategies and marine spatial planning. They urge that gleaning and shallow-water harvesting — activities dominated by women and marginalized groups — be recognized in fisheries governance rather than treated as informal residue. And they recommend that marine protected area design in seagrass regions adopt social safeguards comparable to those used in terrestrial conservation, including participatory zoning, temporary rather than permanent closures, and monitoring of household nutrition alongside ecological indicators. Without such measures, they warn, marine conservation risks widening the very inequalities that undermine long-term stewardship, as communities excluded from resources have little incentive to protect them.

For the millions of people living in poor coastal settlements across the Indo-Pacific, the study gives statistical weight to something they have long known: the green meadows beneath the shallows are not scenery but supper, savings and insurance. As nations negotiate global biodiversity targets and blue economy investments, the research serves as a reminder that the ocean’s contributions to people are distributed unevenly, and that counting them accurately is a prerequisite for conserving them fairly. What happens to seagrass, the study concludes, is inseparable from what happens to the world’s coastal poor — and marine conservation will only succeed as a global enterprise when it learns to see, and protect, both at once.

Subject of Research: The relationship between seagrass-associated fishing and household poverty across Indo-Pacific coastal communities

Article Title: Seagrass fisheries expose the poverty dimensions of marine conservation

Article References: Jones, B. L. H., Unsworth, R. K. F., Ambo-Rappe, R., Carli, F., Coals, L., Digdo, A. A., Eklöf, J. S., Jiddawi, N. S., La Nafie, Y. A., Lopez, M. R., Nordlund, L. M., Septiani, C., Udagedara, S., & Cullen-Unsworth, L. C. (2026). Seagrass fisheries expose the poverty dimensions of marine conservation. Nature Sustainability. https://doi.org/10.1038/s41893-026-01932-6

Image Credits: AI Generated

DOI: 10.1038/s41893-026-01932-6

Keywords: seagrass, marine conservation, poverty, Indo-Pacific, fisheries, coastal livelihoods, food security, marine protected areas, gleaning, ecosystem dependence, blue economy, household surveys