When their home deteriorates, they cannot simply swim elsewhere. They are trapped.
In the shallow reefs of Raja Ampat, a shark that walks rather than swims has become an unlikely mirror for the tensions of our age — between the human desire to witness nature's wonders and the cost of arriving to see them. The epaulette shark, one of only ten walking shark species on Earth, holds the world's densest known population in these Indonesian waters, yet its very stillness is its undoing: it cannot flee what it cannot outswim. Protected by law since 2023 but unguarded in practice, this small, spotted creature now asks a question the modern world struggles to answer — whether a species must prove its economic worth before it earns the right to survive.
- The world's densest population of walking sharks is concentrated in a stretch of Indonesian reef so small that a single construction project above a seagrass bed can sever a shark's entire feeding territory.
- Tourism is accelerating faster than regulation — overwater homestays are rising directly above the nocturnal hunting grounds adult sharks depend on, while untreated wastewater feeds algae blooms that smother the coral nurseries where juveniles shelter.
- Climate change compounds the pressure, with rising sea temperatures threatening to push water beyond the species' 36-degree tolerance threshold and disrupt breeding cycles that are already constrained by the sharks' extreme reluctance to move.
- Indonesia granted the walking shark full protected status in 2023, but the designation carries no habitat conservation plan, no economic incentive for local compliance, and enforcement across the Dampier Strait remains largely symbolic.
- Scientists and conservationists are calling for stronger monitoring and genuine habitat protection, warning that the species' remarkable density — once a sign of ecological health — could become the final statistic before a quiet, localized extinction.
In the shallow waters of Raja Ampat, a remote archipelago in Southwest Papua, lives a shark that walks. The epaulette shark — Hemiscyllium freycineti — moves across the seafloor on its pectoral and pelvic fins, a gait so unusual it has made the species one of the ocean's most distinctive creatures. A study published in June in Frontiers in Fish Science found that Raja Ampat hosts up to 2,462 individuals per square kilometer, the highest population density ever recorded for any walking shark species on Earth.
But that abundance conceals a profound fragility. Researchers tracking the sharks between early 2024 and mid-2025 found that individuals almost never venture beyond 475 meters from their birthplace, and none were observed crossing between islands. Juveniles shelter in coral reefs; adults forage nocturnally across seagrass beds and mangrove roots. These are not preferences — they are survival requirements. And both habitats are under pressure.
Tourism development is the most immediate threat. Homestays and overwater accommodations are being built directly above the seagrass beds where adult sharks hunt at night. At Arborek village, one of six study sites in the Dampier Strait, the collision is already visible. Study lead Edy Setyawan of the Elasmobranch Institute Indonesia described the stakes plainly: when seagrass ecosystems are damaged, the sharks lose the critical resources they cannot travel elsewhere to find. Meanwhile, untreated wastewater from tourist facilities feeds algae blooms that degrade the coral reefs serving as nurseries for young sharks.
Climate change adds a slower but equally serious pressure. The species can tolerate water up to 36 degrees Celsius, but scientists warn that intensifying marine heat waves could stress their physiology and disrupt breeding. Indonesia responded to these converging threats by granting walking sharks full protected status in 2023, and the IUCN listed them as nearly threatened. Yet the regulation bans catching the sharks without providing any plan for habitat conservation. As marine ecologist Agustin Capriati and Setyawan both noted, a species with no perceived economic value generates little political will — and enforcement across Raja Ampat's marine protected areas remains weak.
The government has demonstrated it can respond to high-profile pressure, suspending nickel mining on nearby Gag Island after international protests in 2025. But the quieter, daily work of protecting seagrass beds and monitoring water quality receives far less attention. Without that commitment, the walking shark's extraordinary density may prove not a sign of resilience, but a measure of how much there is left to lose.
In the shallow waters of Raja Ampat, a remote archipelago in Southwest Papua, lives a creature that moves like nothing else in the ocean. The epaulette shark—called the "walking shark" by locals—propels itself across the seafloor using its pectoral and pelvic fins, a peculiar gait that has made it one of the ocean's most distinctive residents. But this small, spotted shark now faces a collision between two forces reshaping its world: the rapid expansion of tourism infrastructure and the creeping effects of climate change.
The Raja Ampat epaulette shark, scientifically known as Hemiscyllium freycineti, belongs to a rare genus of only ten known walking shark species worldwide. Six of these species live primarily in eastern Indonesian waters, making the region a global hotspot for this unusual lineage. What makes the Raja Ampat population particularly remarkable is its density. A study published in June in the journal Frontiers in Fish Science found that these sharks congregate at rates of up to 2,462 individuals per square kilometer—the highest population density ever recorded for the genus anywhere on Earth.
Yet this abundance masks a critical vulnerability. Unlike most marine animals, walking sharks are homebodies. Researchers tracking the species from February 2024 through April 2025 found that individuals rarely venture more than 475 meters from where they were born, and none were observed moving between islands. This sedentary nature, while allowing the sharks to specialize in their local environment, leaves them defenseless against habitat disruption. When their home deteriorates, they cannot simply swim elsewhere. They are trapped.
The study, led by Edy Setyawan of the Elasmobranch Institute Indonesia, revealed how the sharks use their limited territory with precision. Juvenile sharks shelter in coral reefs, which serve as nurseries where young are produced—69 percent of immature sharks were found in these reef systems. Adult sharks, which are nocturnal, forage among seagrass beds and mangrove roots at night. These feeding grounds are not luxuries; they are survival infrastructure. And they are disappearing.
Tourism development in Raja Ampat is accelerating. Homestays and overwater accommodations are being constructed directly above the seagrass beds where walking sharks hunt. Arborek village, one of six study sites in the Dampier Strait, exemplifies this collision. "With the development of tourism in Raja Ampat, many homestays are being built above sea grass beds," Setyawan told The Jakarta Post. "Those sea grass ecosystems are important habitats where 'walking sharks' forage for food. When they are damaged, the sharks lose their critical resources." The irony is sharp: the very waters that draw tourists are the ones the sharks depend on to survive.
Climate change adds another layer of threat. The walking shark can tolerate water temperatures up to 36 degrees Celsius, but scientists worry that global heating will increase the frequency and intensity of marine heat waves. Even brief temperature spikes could stress the species' physiology and disrupt breeding cycles. Beyond temperature, tourism generates nutrient pollution through untreated wastewater. Marine ecologist Agustin Capriati explained that excess nutrients accelerate algae growth, which smothers and damages coral reefs. As coral ecosystems degrade, the juvenile sharks lose their nurseries.
Indonesia recognized the threat. In 2023, the Ministry of Marine Affairs and Fisheries designated walking sharks as a fully protected species, and the International Union for Conservation of Nature classified them as "nearly threatened." But protection on paper has not translated to protection in practice. The regulation prohibits catching or consuming the sharks, but it contains no concrete plan for habitat conservation. Setyawan noted the core problem: "In practice, people know the species exists, but conservation efforts remain limited because the fish is not viewed as having economic value." A species that cannot be sold has little political momentum behind it.
Enforcement remains weak across Indonesia's marine protected areas, including the Dampier Strait where walking sharks live. The government has shown it can act when international pressure mounts—it suspended nickel mining operations on nearby Gag Island in May 2025 after Greenpeace protests, though it allowed mining to resume the following September. But day-to-day habitat protection, the unglamorous work of stopping construction in seagrass beds and monitoring water quality, receives far less attention. Without stronger enforcement and a genuine commitment to preserving the ecosystems these sharks depend on, their remarkable density may become a footnote in a story of decline.
Notable Quotes
Those sea grass ecosystems are important habitats where 'walking sharks' forage for food. When they are damaged, the sharks lose their critical resources.— Edy Setyawan, Elasmobranch Institute Indonesia
In practice, people know the species exists, but conservation efforts remain limited because the fish is not viewed as having economic value.— Edy Setyawan
The Hearth Conversation Another angle on the story
Why does it matter that these sharks don't move far? Plenty of animals have small home ranges.
Because they can't escape. If a coral reef dies or a seagrass bed gets paved over, most fish can swim to new habitat. Walking sharks are stuck. They evolved to thrive in one place, which made them efficient hunters there—but it also made them fragile.
The study found nearly 2,500 sharks per square kilometer. That sounds robust. Why are we worried?
Density without mobility is a trap. You can have a million individuals in one location, but if that location gets damaged, you lose them all. They're not spreading risk across the ocean. They're concentrated in a few vulnerable spots.
Tourism brings money to Indonesia. How do you balance that against a shark most people will never see?
That's the real tension. The homestays and resorts are legal, they employ people, they generate tax revenue. But they're built directly on the feeding grounds. It's not tourism versus sharks—it's one kind of economic value against another kind. The question is whether anyone is asking if the trade-off is worth it.
The government already protected the species. Isn't that enough?
The protection only says you can't catch them. It doesn't stop you from destroying their habitat. It's like making it illegal to hunt an animal while allowing someone to bulldoze the forest it lives in. The law exists, but it doesn't actually protect what the sharks need to survive.
What would real conservation look like?
Enforced no-build zones in seagrass beds. Wastewater treatment for tourism facilities. Monitoring to catch habitat damage before it spreads. And honestly, a reason for local communities to care—right now, the shark has no economic value, so there's no incentive to protect it. That's the hardest part to fix.