Speckled peacock bass

Peacock bass seasonality in the Amazon and Orinoco basins is the inverse of a temperate fishery: the good period is the low-water one.

FALLING AND LOW WATER CONCENTRATES THEM. During the flood, fish disperse into inundated forest and floodplain over an enormous area and are effectively unreachable. As water falls, they are forced back into lagoons, channels and river margins, where they concentrate and where the water clears.

CLEAR WATER IS THE OTHER REQUIREMENT. Peacock bass are visual ambush predators, and the sport fishery depends on being able to see and be seen — which is why it operates on clearwater and blackwater tributaries rather than on the turbid whitewater mainstem, and why it follows the falling hydrograph.

SO THE SEASON IS HYDROLOGICAL, NOT THERMAL. Water temperature barely changes across the year; water level changes by many metres, and it is the level that decides everything.

DIFFERENT TRIBUTARIES DROP AT DIFFERENT TIMES, so the regional season moves between river systems across the year, and operators follow it.

SPAWNING OCCURS IN THE LOW-WATER PERIOD in shallow margins, with pairs clearing a site and guarding eggs and fry — so the concentrated fishing season and the reproductive season overlap, which is a real consideration rather than an incidental one.

AND EL NIÑO AND YEAR-TO-YEAR HYDROLOGY MOVE THE SEASON. An unusually high or prolonged flood delays or shortens it, and a season is a prediction about a river rather than a date in a calendar.

Speckled peacock bass are handled in the hottest conditions any species in this catalogue is regularly fished in, and the two things that go wrong both follow from that rather than from the fish's anatomy.

THE FIRST IS THERMAL. Amazonian air temperatures in the dry season are extreme, and a fish lifted out of water at thirty degrees into air at forty is losing its oxygen supply at the moment its oxygen demand is highest, having just fought hard in warm water that holds relatively little to begin with. Peacock bass fight in short, violent bursts that run deep into anaerobic metabolism, and the recovery from that requires exactly the oxygen the situation is not providing. A fish held up for a photograph in that heat is being asked to do the impossible, and it is a fishery where the photograph is very much the point for most visiting anglers.

What works is the same everywhere and matters more here: the fish stays in the water, is supported horizontally with a wet hand under the belly, is photographed at the surface rather than held up, and is given time facing into whatever current there is.

THE SECOND IS BEHAVIOURAL AND IT IS AN ETHICAL QUESTION RATHER THAN A TECHNICAL ONE. Peacock bass are substrate-spawning cichlids with intense parental care: a pair guards a mass of fry and attacks anything that approaches. That aggression is a large part of why the fishery works — a lure worked near a guarded brood is attacked because it is a threat, not because it is food — and it means the fish most reliably caught during the spawning period are guarding parents. A guarding fish removed from its brood, even briefly, leaves the fry undefended in water full of predators, and a fish removed permanently leaves them to fail entirely.

The honest statement is that this is a real cost, that it is inherent in the method rather than incidental to it, and that returning such fish immediately and to the spot they came from is the minimum. Whether to fish guarded broods at all is a judgement each angler and each operation makes.

Peacock bass habitat is narrower than their reputation suggests, and the narrowness explains exactly where in an Amazonian system they are found.

THEY NEED SLOW OR STILL WATER, WHICH IS THE KEY CONSTRAINT. Despite living in one of the world's great river systems, peacock bass avoid strong current. They occupy lagoons, backwaters, flooded forest margins, oxbows, lake-like river widenings and the slack water behind structure — and they are largely absent from fast main-channel flow. A visitor expecting to fish a big river for them is looking at the wrong water.

WATER CLARITY MATTERS BECAUSE THEY HUNT BY SIGHT. Peacock bass are visual ambush predators, and they are strongly associated with the clearer black-water and clear-water systems rather than with heavily silted white-water rivers. Where a river is turbid, they are scarce, and this is a substantial part of why particular tributaries are productive and adjacent ones are not.

STRUCTURE IS WHERE THEY HOLD. Fallen timber, submerged trees, rock, sandbars, weed edges, and the boundary between flooded forest and open lagoon. They are ambush predators taking small fish over a short distance, and they position accordingly.

TEMPERATURE SETS THE RANGE ABSOLUTELY. These are tropical fish with no cold tolerance, which confines them to warm water and is what limits established introduced populations to the warmest parts of the countries they have been moved to.

THE WATER LEVEL CYCLE MOVES THE WHOLE HABITAT. On a high flood the fish disperse into inundated forest and are effectively unreachable; as levels drop they concentrate in lagoons and channels with the prey that is being forced out with them. That falling-water concentration is the habitat's most important seasonal property, and it is the same flood-pulse mechanism the tigerfish and mahseer records describe on other continents.

AND THE FISH GUARD THEIR YOUNG, which ties the habitat to shallow protected margins for part of the year in a way an open-water predator's does not.

Peacock bass reproduction is unusual in this catalogue because both parents stay, and the consequences of that run through the whole fishery.

A PAIR CLEANS A SITE AND SPAWNS ON IT. Peacock bass are substrate spawners: a pair selects and cleans a hard surface — rock, submerged wood, compacted sand — in shallow protected water, and the female deposits adhesive eggs on it. There is nothing casual about the site selection and the pair will defend it before spawning as well as after.

BOTH PARENTS THEN GUARD, WHICH IS THE DISTINCTIVE PART. Unlike the single guarding male of a largemouth bass nest, peacock bass pair-bond through the brood period and both fish defend the eggs and then the shoal of fry, driving off anything that approaches. The fry are herded as a dense visible cloud and shepherded through shallow water for a considerable period.

WHICH MAKES THE GUARDING PAIR EXTRAORDINARILY AGGRESSIVE AND EXTRAORDINARILY VULNERABLE AT ONCE. A guarding peacock bass attacks anything near the fry including lures, which is the reason the fishing over broods is so easy and the reason it matters: removing either parent exposes the whole brood, and removing both effectively ends it.

THE TIMING FOLLOWS THE WATER LEVEL RATHER THAN THE MONTH. Spawning is concentrated in the low-water and falling-water period when lagoon and margin habitat is stable and shallow, which is the same part of the cycle that concentrates the fishing. That coincidence — best fishing and peak reproduction in the same weeks — is the central management tension for the species.

MULTIPLE BROODS ARE POSSIBLE within a season where conditions allow, which gives some resilience.

AND THE HONEST CONCLUSION IS ABOUT RESTRAINT RATHER THAN TECHNIQUE. A visibly guarding pair with fry is the easiest fishing available and the most costly, and returning such fish quickly and moving on is the practice the better-run fisheries encourage. What any jurisdiction requires is a matter for the competent authority.