Thailand's catch-and-release culture has evolved rapidly over the past two decades, driven primarily by the private pay-lake sector rather than government regulation. The result is a situation where the rules vary significantly depending on where you are fishing — and where the most rigorous protections are often venue policy rather than law.
Understanding what is required, what is voluntary, and how to handle fish correctly in tropical water temperatures is not optional if you are targeting the country's larger, more ecologically significant species.
The Short Answer
At premium specimen pay-lakes — and for specific species regardless of location — catch and release is either mandatory by venue rule, legally protected, or both. The species and venues where you have no choice are:
- Arapaima: Mandatory C&R at all Thai venues. These are stocked fish; killing them is destroying the venue's primary asset, and in practice they are never killed at any legitimate operation.
- Giant freshwater stingray: Critically endangered. All reputable operations require release.
- All mahseer: Catch and release is the expected and ethical standard across all venues and wild fisheries targeting this species.
- Sailfish: Thailand's billfish are required to be released alive under Thai fisheries regulations covering these species on commercial and charter operations.
- Gillhams Fishing Resort and comparable premium specimen lakes: Strict catch-and-release required for all species, enforced by venue staff.
- Most premium Bangkok-circuit specimen lakes: C&R for all designated specimen fish, which typically means anything over a certain size or listed as a specimen species.
Where fish are retained — some smaller bait fisheries at local pay-lakes, some saltwater species on commercial charters — the expectation is explicit and stated at the venue. If no one has told you the fish you just caught can be kept, assume it cannot.
Venues Where C&R Is Mandatory
Gillhams Fishing Resort (Krabi)
Gillhams Fishing Resort operates one of the most rigorous catch-and-release programmes in Southeast Asian freshwater fishing. All catches are released — arapaima, Mekong giant catfish, Siamese giant carp, pacu, alligator gar, and the full specimen inventory. The guides are trained in proper handling and will correct technique actively during your session. There is no grey area here.
IT Lake Monsters (Bangkok)
IT Lake Monsters runs a mandatory C&R policy for all its stocked species, which include giant snakehead, arapaima, Chao Phraya catfish, and Siamese carp. The policy is enforced and the venue's guides are attentive to handling.
Pilot 111 / Palm Tree Lagoon and Similar Bangkok-Circuit Specimen Lakes
The better-managed specimen lakes on the Bangkok circuit operate on the same mandatory C&R basis. The logic is commercial as well as ethical — the fish in these lakes represent a significant investment, and killing them is not permitted for exactly the same reason a golf course does not let you take the greens home.
Ask before you assume
Smaller, less well-known pay-lakes may have mixed policies — C&R for listed specimen fish and "keep what you catch" for smaller species. Always confirm the policy at reception before your session begins.
Legally Protected Species in Thai Waters
Beyond venue rules, certain species carry legal protection under Thai fisheries and environmental law.
Giant freshwater stingray (Urogymnus polylepis) are classified as critically endangered by the IUCN and are subject to protection under Thai law. Intentionally targeting them for retention is not permitted. Catch-and-release fishing for giant stingray — which does take place at specialist operations along the Mae Klong and Bang Pakong rivers — is conducted by specialist guides who understand safe handling of these animals. This is not a species for casual pursuit; the handling demands alone require experience.
Mahseer (Tor spp.) — particularly the critically endangered Siamese giant carp relatives found in northern Thailand — are subject to protections in their native river systems. Reputable mahseer fishing operations run exclusively on a catch-and-release basis, and the access agreements with local communities that make this fishing possible are predicated on that commitment.
Sailfish and billfish: Thailand is a signatory to international agreements covering billfish, and Thai charter operators targeting sailfish — particularly on the Koh Rok sailfish grounds — operate on mandatory release policies. A sailfish that comes to the boat is unhooked and released. This is not merely a conservation preference; it is the operating norm and increasingly the legal position.
When Fish Are Killed
Not every Thai fishing operation is catch-and-release. Being clear about where retention is acceptable prevents confusion.
Local bait fisheries: Many smaller Thai pay-lakes — the category that serves local recreational anglers rather than international specimen hunters — operate on a keep-what-you-catch basis for certain species. Smaller catfish, freshwater snappers, and tilapia variants may be purchased by weight at the end of a session. This is entirely legitimate and culturally normal. The fish in these operations are typically farmed species stocked for this purpose.
Saltwater pelagics (where permitted): On some Gulf of Thailand and inshore Andaman charters, keeping a yellowfin tuna, a cobia, or certain reef fish for eating is acceptable and common. The distinction here is species: billfish are not kept, but a 20 kg yellowfin on a trolling charter is often headed for the barbecue, which is standard practice on charter fishing worldwide.
Community fisheries: Some reservoir fishing arranged through local guides operates on a system where a proportion of catch may be retained as agreed with the community. This is specific to the local arrangement and will be explained to you before fishing.
The dividing line is usually either explicit venue policy or species protection. When in doubt, release.
The Legal vs. Ethical Distinction
Thai law sets a baseline. Venue policy often goes further. Your own ethical position may go further still.
The honest framing: even where retention is technically permitted, some species have population dynamics that make recreational killing difficult to justify. Giant snakehead, for instance, are not legally protected, but the top-tier specimen snakehead venues — and most serious snakehead lure anglers — practice strict C&R because wild snakehead are a finite resource that cannot be easily restocked and a species whose sporting value is destroyed by removal.
This is a distinction worth having a view on before you go. If you are fishing for food, certain venues and certain species are appropriate contexts. If you are fishing for the sport of targeting large, wild-ish specimens in managed environments, the ethical expectation from the broader community of anglers who do this is release.
The fish you release at Gillhams today will be caught by someone else next week. That is not a bug in the system — it is the entire point of it.
How to Release Fish Correctly in Tropical Water
This is where good intentions fail if technique is poor. Tropical water temperatures — typically 28–32°C at Thai lake and river venues — mean fish are already operating closer to their physiological limits than fish in cold-water environments. A poorly handled release in warm water can cause a fish to die hours after it is returned, even if it swam away apparently strongly.
Wet Your Hands
Always. Dry hands remove the protective mucus layer from fish skin, increasing susceptibility to infection. This is not a courtesy — it is a basic functional requirement of safe handling.
Keep the Fish in or Near the Water
For photography and handling, keep the fish's body supported at or below the water surface as much as possible. A large Mekong catfish or arapaima weighing 30–80 kg should never be fully supported by its jaw — the internal organ damage from vertical suspension of that mass is significant. Support the body lengthways, with the fish horizontal.
For smaller fish that are lifted briefly for a photograph, minimise the time out of the water. The general guideline used by catch-and-release operations worldwide is: if you cannot hold your own breath for as long as the fish has been out of the water, it has been out too long.
No Gravel, No Dry Ground
Do not lay fish on dry ground, concrete, grass, or gravel. If the fish needs to be placed down briefly, lay it on the wet unhooking mat that good venues provide, or keep it in the water and net.
Unhooking
Use forceps or a proper unhooker for deeply-set hooks rather than pulling with your fingers. Long-shank hooks, which cause less deep-hooking in the first place, are worth using specifically for this reason — see What to Pack for Fishing in Thailand for the tackle recommendations.
If a fish has swallowed the hook, the correct decision in a catch-and-release fishery is to cut the trace as close to the hook as possible and leave the hook in place. A hook left in a fish will rust and pass; the damage from attempting to remove a deeply embedded hook in a warm-water fish with poor oxygen availability is far worse.
The Recovery and Release
Hold the fish upright in the water — laterally stable, facing into any current if present, or simply stationary — and wait. Do not let go when the fish first makes a movement; wait until it actively pulls away from your hands under its own power. In warm water, this recovery period can take several minutes for a heavily fought fish. Do not rush it.
At venue operations, the staff will typically manage the recovery and release. Watch how they do it. The technique is worth learning for any situation where you are handling a fish yourself.
The Specific Species That Need Special Attention
Arapaima: Air-breathing; can be kept in shallow water briefly while being unhooked. Do not flip upside down. Firm lateral support. These fish often self-recover quickly once back in water.
Giant freshwater stingray: Do not attempt to handle alone. The spine is dangerous and the fish requires two people to safely support and guide back to depth. This is a guide-managed release, full stop.
Giant Mekong catfish: Heavy, muscular, and strong-fighting. Recovery time in warm water can be extended. Keep the fish in the water throughout the recovery phase. Do not lean the fish against the bank.
Mahseer: Native river fish, not stocked. The stress of capture in warm water is significant. Minimise handling time strictly. Mahseer specialists often do not lift the fish from the water at all — the photograph is taken with the fish held at the surface.
Where to Go Next
- Pay-Lake Etiquette in Thailand — the full culture guide for conduct at venues
- Giant Freshwater Stingray — species guide and the specialist operations that target them
- Gillhams Fishing Resort — one of Southeast Asia's premier specimen venues and its C&R programme
- Do Tourists Need a Fishing Licence in Thailand? — the regulatory picture that underpins species protections
- Arapaima — the world's largest scaled freshwater fish and Thailand's iconic stocked specimen
