A new study by Universitas Hasanuddin researchers, published in the international journal Maritime Studies (Springer, 2026), reveals how families on one of Indonesia’s most crowded coral islands are extending their homes into the sea and why this ingenious survival strategy carries a hidden cost.
On Barrang Lompo, a twenty-hectare coral island floating some fourteen kilometres off the coast of Makassar, land has simply run out. More than 5,000 people live packed into one of the highest population densities recorded among Indonesia’s small islands. Every square metre of solid ground is already occupied. So when a family grows, when a daughter marries, or when a storm tears away part of the shoreline, residents do the only thing left to them: they build outward, over the reef, into the water itself.
This everyday act of survival is the subject of a new article, “Maritime Urbanism and the Resilience Paradox: Spatial Saturation, Informal Adaptation, and Everyday Survival on Barrang Lompo Island, Indonesia,” authored by Ahmad Ismail, Munsi Lampe, Pawennari Hijjang, Hardiyanti Munsi, Andi Batara Al Isra, and Abdul Masli. Drawing on months of maritime ethnography, living alongside the community, interviewing thirty-five residents, and joining fishers, boat owners, women fish-processors, and elders in their daily routines, the study documents a phenomenon the authors call urbanism without land.
Building a city on the water
Across the island’s edge, households construct stilt houses and small seawalls above the shallow reef flats, using family labour and salvaged materials. Piece by piece, the boundary between solid ground and open sea dissolves. What was once ocean becomes an inhabited zone: a hybrid space where dwelling, mobility, and fishing all unfold together.
The researchers frame this through the lens of maritime urbanism the idea that the sea is no longer merely a boundary or a resource, but an extension of urban life itself. Barrang Lompo, they argue, is an emergent case of the “urbanization of the sea,” a living example of how coastal communities across Southeast Asia are being pushed to reimagine where a city can exist.
Crucially, these adaptations are not random. They are woven into deep moral obligations, the duty to keep kin close, to shelter a married child, to rebuild after a storm. Survival here runs on reciprocity, honour, and trust rather than on formal planning. One fisherman’s wife described the local credit network known as utang sirik, or “debt with honour,” with a laugh: “We borrow because shame is smaller than hunger.” Before the waves, families still gather for the doa selamatan laut, the sea blessing prayer, invoking ancestral spirits and divine mercy to “hold the waves.” Adaptation on Barrang Lompo, the authors note, is at once material, social, and spiritual.
The resilience paradox
Yet the study’s central finding is a sobering one. The very practices that keep families afloat in the short term are quietly undermining the island’s long-term survival. The authors name this the resilience paradox.
When each household defends its own patch of coast, the collective loses. Private seawalls deflect waves onto a neighbour’s home, displacing hazards rather than resolving them. Common marine space once shared by the whole community becomes privatised, parcel by parcel. And the construction itself takes an ecological toll: overwater growth and rubble-based armouring alter water flow, trap waste, and smother the coral reefs that protect and feed the island. The result is a slow erosion of the very foundations the community depends on.
In other words, as the researchers put it, the island’s capacity to persist is being secured at the expense of its capacity to adapt collectively. Resilience, the study shows, is not always a positive force. On small islands under extreme pressure, it can be ambiguous and even self-defeating, a short-term rescue that deepens long-term vulnerability. This matters enormously given the stakes: earlier research projected that more than 80 percent of Barrang Lompo’s land area could be inundated by 2100 without adaptation.
Rethinking how we help
The findings carry a clear message for policymakers. Top-down interventions, bans on overwater construction, or purely engineering-led sea defences are likely to fail because they ignore the household logics that drive these adaptations in the first place. Informal building should not be dismissed as disorderly or illegal, the authors argue, but recognised as an existing grammar of survival through which islanders negotiate risk, space, and belonging.
What Barrang Lompo needs instead is community-based spatial governance: an approach that coordinates households rather than controlling them, aligns scattered private defences into shared protection, and restores ecological function along the coast. The study points to promising directions community-designed edge typologies, living-shoreline experiments adapted to coral settings, and pooled materials and credit governed by transparent rules. The challenge, the authors write, is to “reassemble resilience upward”: to preserve the ingenuity that sustains families at the water’s edge while rebuilding the collective institutions and healthy ecologies that sustain the whole island.
About the research
The study was conducted with the support of the Institute for Research and Community Service (LPPM), Universitas Hasanuddin, through the Thematic Research Group (TRG) Grant Scheme, Batch 5, 2025. The team also thanks the Antropos Indonesia Foundation for its collaboration during fieldwork, and the residents and leaders of Barrang Lompo for their hospitality and participation.
The full article is available in Maritime Studies (2026) 25:45.
Read the full paper: https://doi.org/10.1007/s40152-026-00506-8