Can climbing perch really climb trees?

Not quite. They can haul themselves across wet ground using their gill covers and pectoral fins, sometimes ascending low banks or vegetation at the water's edge, but extended tree-climbing is folklore. The name comes from early Western observers who found them in trees — likely washed there by floods.

Is climbing perch good to eat?

Yes — it's a staple protein across Southeast Asia, particularly in rural Thailand, Myanmar, and Bangladesh. The flesh is firm and flavourful, though the fine bones require care. It is commonly fried whole or made into a dry-salted preparation.

What bait works best for climbing perch?

Small earthworms, maggots, freshwater shrimp, and pieces of chicken intestine are all effective. Float fishing a small worm just off the bottom in shallow paddy channels produces reliably.

What tackle weight do I need?

Ultra-light is ideal — a 1–3 g spinning rod or a simple cane pole with 4–6 lb mono. Climbing perch rarely exceed 200 g, and heavy gear is simply unnecessary.

Do climbing perch survive drought?

Yes. The labyrinth organ allows them to breathe atmospheric air, and they can survive considerable periods out of water in damp mud or leaf litter. This is precisely how they colonise isolated paddies and ditches during the wet season and survive when those water bodies dry out.

Are climbing perch found in Bangkok?

They persist in some of Bangkok's older khlongs (canals) and suburban drainage channels, though habitat loss and water quality have reduced their abundance in the capital. They are far more common in rural central plains, Isan, and northern provinces.

What is the Thai name for climbing perch?

Most commonly pla mor (ปลาหมอ), though regional variants exist. 'Mor' can translate loosely as 'doctor', a reference whose exact origin is disputed — some sources link it to the fish's perceived toughness and ability to survive.

Climbing Perch: Thailand's Most Resilient Native Fish

There is a fish in Thailand that can walk. Not metaphorically — it will haul itself out of a drying paddy, work its body across twenty metres of damp grass using its gill covers as improvised crutches, and drop into the next ditch before the heat of the day is done. The climbing perch (Anabas testudineus), known locally as pla mor, is one of the strangest and most adaptable native fish in Southeast Asia. It is also, for anglers willing to fish light, a charming and rewarding target.

Species Overview

The climbing perch belongs to the family Anabantidae, sharing ancestry with the gouramis, bettas, and snakeheads — all members of the suborder Anabantoidei, defined by possession of the labyrinth organ. This suprabranchial structure, tucked into a chamber above each gill arch, functions as a rudimentary lung, allowing the fish to extract oxygen directly from air. It is this adaptation, evolved for life in warm, poorly oxygenated tropical shallows, that underlies every remarkable thing about pla mor's biology.

Adults typically reach 15–20 cm in length with a maximum around 25 cm. The body is deep and laterally compressed, covered in rough ctenoid scales that extend partway onto the head. Colouration is variable — generally olive-brown on the back shading to pale yellow or cream on the belly, with faint darker barring along the flanks. The dorsal and anal fins bear short but sharp spines, and the gill covers carry a prominent dark spot edged in gold that helps distinguish the species at a glance. It is not a showy fish, but closer inspection reveals a quiet elegance.

Climbing perch are native across a vast range from India through Southeast Asia to southern China and the Philippines. In Thailand they occupy almost every permanent and seasonal freshwater habitat below roughly 500 m elevation — rice paddies, irrigation channels, roadside ditches, oxbow lakes, and the sluggish margins of larger rivers.

Habitat and Distribution in Thailand

Pla mor is genuinely ubiquitous in rural Thailand. Drive through the central plains during the wet season and every flooded paddy carries a population. Fish the irrigation margins of Chiang Mai Province or the seasonal ponds of Isan and you will find them. This distribution reflects the species' extraordinary ecological tolerance: climbing perch withstand temperatures from around 20°C to well above 35°C, tolerate very low dissolved oxygen, survive in brackish water up to roughly 10 ppt salinity, and — as noted — endure extended periods ashore.

Their overland movement ability is not merely a curiosity. It is a genuine ecological strategy that allows pla mor to exploit temporary water bodies unreachable by other species, colonising new habitats after floods and escaping desiccating pools before stranding becomes fatal. Early European naturalists who encountered fish apparently perched in low vegetation near water's edge coined the "climbing" name; modern understanding suggests these individuals were more likely attempting lateral migration rather than vertical ascent, but the name stuck.

In drier months, look for pla mor in permanent irrigation channels, village ponds, and the deeper pools of slow streams. As the rains arrive and paddies flood, fish spread widely and are encountered almost anywhere there is standing water with emergent vegetation.

Cultural and Culinary Significance

In rural Thailand, the climbing perch is not a sport fish — it is a food fish, and an important one. Generations of rice-farming families have relied on pla mor as an accessible, dependable protein source that can be caught from the fields themselves with nothing more than a hand line and a worm. The fish is versatile in the kitchen: fried whole until crisp, braised with galangal and lemongrass, fermented into pla ra (a pungent preserved fish paste foundational to Isan cuisine), or dried and salted for storage during lean months.

"For generations of Thai rice farmers, pla mor was not a fish you fished for — it was a fish the land provided. Finding one in a drying paddy was practical providence."

The fish appears in Thai folk medicine traditions and in local proverbs, where its hardiness is invoked as a metaphor for resilience. Temple ponds often harbour populations that have been sustained by merit-release (the Buddhist practice of releasing live animals), and the species carries mild auspicious associations as a survivor.

Fishing for Climbing Perch

From a sporting perspective, pla mor is a beginner's fish and a light-tackle specialist's fish simultaneously. For newcomers to Thai freshwater fishing — children learning to cast, travellers wanting a relaxed hour at a village pond, anglers introducing younger family members to the sport — it is ideal. For those who fish ultra-light and find satisfaction in maximising the fight from small species, it offers genuine challenge.

Tackle

There is little point using anything heavier than ultra-light. A 1.2–1.5 m telescopic rod rated for lures to 3 g, or a simple 2–3 m cane or fibreglass pole, is perfect. Line should be 4–6 lb monofilament or 4 lb fluorocarbon for clear-water situations. Hook sizes of 6–10 on a light wire pattern suit the fish's modest mouth size. A simple float rig set to fish 20–30 cm off the bottom covers most situations in paddy channels and irrigation margins.

Those interested in micro-lure fishing can take climbing perch on tiny spinners (size 00–0), micro jig heads tipped with small soft plastics, and even small dry flies fished on a tenkara-style rod. The fish are opportunistic predators, taking aquatic insects, small crustaceans, worms, and occasionally very small fish or tadpoles. They respond to subtle presentations with a decisiveness that belies their size.

Bait

Small earthworms are the classical bait and remain the most effective. A piece of worm roughly 2–3 cm long, hooked once through the head and left to wriggle naturally under a float, is difficult for a pla mor to resist. Other reliable options include:

Maggots / gentles: Two or three on a small hook fish well, particularly in cooler or clearer water.
Freshwater shrimp: Small live shrimp are excellent where available. Small dried shrimp work as a less active alternative.
Chicken intestine: A traditional Thai bait, cut into small pieces and fished on a small hook. Highly effective, particularly in murky paddy water where scent is more important than visual appeal.
Commercial paste baits: Thai fishing shops sell small pots of flavoured paste designed for small native species; these work adequately for pla mor.

Technique

Patience more than technique defines successful pla mor fishing. Locate structure — clumps of aquatic grass, submerged vegetation, the margins of lotus patches, the edges of wooden jetties in village ponds — and present bait at or just above the bottom. Climbing perch are largely ambush predators and do not range far from cover. Watch your float for the confident dip that signals a take; they tend to mouth bait briefly before committing, so a half-second pause after the float goes under before striking improves hookup rates.

In warm, shallow water during the hot season (March–May), pla mor congregate around permanent water features and are highly catchable. During the wet season they disperse across flooded paddies and are harder to locate but easy to catch wherever found.

When fishing paddy channels, work the edges rather than the open centre. Climbing perch hold in cover and along the interface between aquatic vegetation and open water. A float rig cast to within 30 cm of a clump of grass consistently outfishes one dropped in the middle of open channel.

Conservation Status and Pressures

Anabas testudineus is currently assessed as Least Concern by the IUCN, and populations remain broadly healthy across most of its Southeast Asian range. However, there are localised pressures worth acknowledging. Agricultural intensification, increased pesticide and herbicide use in rice cultivation, and conversion of seasonal wetlands to permanent agriculture have reduced habitat quality in some regions. In urban and peri-urban areas, water pollution has eliminated populations from waterways that historically supported them.

The species' extreme hardiness means it is more resistant to habitat degradation than most co-occurring fish, but it is not immune. In areas where traditional paddy farming with its seasonal flooding cycles has been replaced by intensive monoculture with chemical inputs, pla mor abundance has declined.

The species is also farmed commercially at modest scale in Thailand, largely for domestic consumption and for the bait-fish trade. Farm-raised fish are occasionally sold in markets alongside wild-caught individuals, making the two hard to distinguish. There is no evidence that aquaculture escapes present a genetic concern given the species' native status across the region.

Sustainability and Catch-and-Release

Climbing perch are extremely hardy fish that survive catch and release well, provided handling is careful. Their ability to breathe air means that brief air exposure during unhooking does not cause the stress it would in a gill-breathing species. Keep the fish wet where possible, use barbless or de-barbed hooks for easier removal, and return the fish promptly. For small specimens, the wet-hand grip with the fish horizontal is sufficient.

Given the species' cultural role as a food fish, many anglers fishing village ponds will keep their catch — this is entirely reasonable, and climbing perch make excellent table fare. Where practising catch-and-release at recreational fishing venues, observe any venue-specific rules.

Thailand holds several other small native labyrinth fish likely to be encountered alongside pla mor. The snakeskin gourami (Trichopodus pectoralis) occupies similar paddy and canal habitats. The three-spot gourami (T. trichopterus) is widespread in similar environments. The kissing gourami prefers slightly deeper, more vegetated water but shares habitat in some locations. None of these are climbing perch — all are more elongate and lack the climbing perch's distinctive rough scaling and gill-cover spine — but novice anglers sometimes confuse them.

The walking catfish (Clarias batrachus) shares pla mor's remarkable overland movement ability and is similarly common in paddy habitats; the two species are often caught together. For anglers seeking larger labyrinth fish, the giant snakehead and giant gourami represent step changes in both size and tackle requirements.

Practical Information

Climbing perch require no specialist planning to target. Rural village ponds, irrigation canal margins, rice paddy channels during the wet season, and temple ponds in country areas all hold fish. Permissions vary — small village ponds may require asking locally, while public irrigation channels are generally open. No fishing licence is currently required for recreational angling in Thailand, though catch-and-release best practice applies regardless.

Tackle costs are minimal: a small telescopic rod, a simple float and hook kit, and a container of earthworms obtained from any Thai market or fishing shop is all that is needed. This accessibility makes pla mor an ideal introductory species for visitors exploring Thai freshwater fishing for the first time, or for anglers taking a half-day away from heavier species targeting at pay-lakes to reconnect with simpler pleasures.

For those interested in the broader ecology of Thai freshwater habitats, the climbing perch is an excellent gateway species — a fish that, in its adaptability and cultural embeddedness, tells you something true about the landscape it inhabits.

ThaiAngler species profiles are written for informational purposes. Always follow local fishing regulations and venue rules. Practise catch-and-release where appropriate and handle all fish with care.

Climbing Perch: Thailand's Walking Fish