What is a Peacock Bass?
Well, first of all, it's not a bass. It's a Cichlid. In fact, although this sounds like such a simple question that it shouldn’t merit more than a sentence or two for an answer, it's actually far more complex than it seems. Depending on your interest, there’s a whole array of answers; a general answer, an aquarist’s answer, a scientist’s answer and an angler’s answer. Since this is, of course, a fisherman’s website, it’s the angler’s answer we want to get to. In order to address it in its full context, we’ll take a look at all the information and drill down to what’s important to the angler.
Let's begin with a general overview of the genus Cichla. This will let us define what fishes we’re actually referring to when we use the term “peacock bass”. As we indicated above, the common term “bass” is not a particularly appropriate descriptor. Taxonomically, it’s a Cichlid. Within the family Cichlidae, the genus Cichla is comprised of fifteen different Neotropical species. (For more information about peacock bass classification, see our Peacock Bass ID Guide. All fifteen species share certain similarities. They are relatively large, diurnal (active in daylight) predators and they are primarily piscivorous (fish eaters). All are commonly known as ‘Peacock Bass’ in English, ‘Tucunaré’ in Brazil and ‘Pavon’ in Spanish speaking countries. They are of significant commercial importance in Amazonia, both as a sportfish and for human consumption.
Although at a casual glance all of the species might appear to be quite similar, there are significant differences among them. This has caused much confusion and misperception, especially among novice peacock bass anglers. It’s when we start looking at their habitat, behavior and life history individually that significant differences become apparent between the species. Some live in roiling fast water. Some live in meandering flood pulse river systems. Some are pursuit feeders and some opportunistic. Some readily attack on the surface while others rarely do. Some average a pound or two while others can exceed twenty nine pounds. These differences are all-important from the angler’s point of view. Although all of them can be fun to catch, only one species in particular has earned the reputation of the world’s most powerful and challenging freshwater gamefish. Cichla temensis, known as the three-barred, speckled, or giant peacock bass is the largest, most powerful and most aggressive of all the species and the one that anglers really dream to travel in pursuit of. With fourteen other, very different animals sharing the same common name, it’s easy to see why the reputation of Cichla temensis has been victimized by confusion with other species.
The true giant peacock bass is not found outside of the Amazon basin. You can’t fish for them in Florida or Hawaii or Panama because they simply aren’t there. Cichla temensis’ natural range consists primarily of blackwater flood pulse rivers with extremely variable seasonal environments in South America’s Amazon regions. The species occurs naturally in Brazil, Venezuela and Columbia. They are native to the Rio Negro basin, Rio Branco basin and lower Rio Madeira basins in Brazil and in the Orinoco and upper Rio Negro drainages in Venezuela and Columbia. Populations are also recorded in several blackwater tributaries of the Rio Solimoes and Rio Amazonas. Unlike some of its smaller cousins, efforts to introduce C. temensis into other regions have mostly failed, probably because of a greater sensitivity to cold or variable temperatures. The only notable exception has been Lake Guri in Venezuela. Other, smaller Cichla species however, have been successfully introduced into more accessible regions, such as several lakes and reservoirs in Brazil, Panama, Hawaii and the canals of South Florida. It is these species that anglers commonly encounter on tourist vacations and it is the misunderstanding that these are the same as the giant Amazon peacocks that has fostered the confusion and misinformation that plagues the peacock bass fishing domain.
So if not every peacock bass is Cichla temensis, what is Cichla temensis? The species that commands angler’s adulation is big, with 15 lb. trophies common and with hulking monsters over 25 lbs. lurking in the waters. They are primarily piscivorous feeders and are pursuit hunters. That means their target is fish and once they decide something is food, they’ll run it down halfway across a lagoon if they have to. And, unlike most of the smaller species, they aggressively strike lures on the surface, violently and with abandon, hence Larry Larsen’s famous description of “Peacock Bass Explosions”. This is probably the most exciting predatory attack of any sportfish in the world. Frankly, no other freshwater fish compares, anywhere.
Amazon peacocks live in the most pristine and exotic habitats on earth. Jungle lined-blackwater rivers, hidden lagoons and white-sand scalloped beaches are just some of the spectacular settings in their native environment. The alien-appearing, isolated still waters lend a counterpoint to their sudden, violent and explosive attacks. And, there are lots of other fish, ranging from acrobatic aruana to hulking giant catfish. Even if there were no fish at all, the Amazon environment alone creates a hauntingly beautiful experience.
This species has adapted to a unique ecosystem. The central Amazon basin experiences a yearly water level pulsation, akin to a gigantic once-a-year tide. With water levels rising and falling from 20 to 40 feet during each year, these fisheries undergo astounding changes. Amazon peacock bass have evolved behaviorally and physiologically in response to these unique conditions. They feed, spawn and undergo remarkable physical changes during the Amazon basin’s flood pulse cycle. Most importantly, from a fisherman’s point of view, they become highly concentrated, aggressive, accessible and hungry during the falling water period. This creates optimal conditions for anglers and coincides, of course, with our fishing season.
Why so much confusion over their name?
- Well, because they've inadvertently been given a few different ones. And they've been given different names because they undergo a dramatic color, pattern and shape change in concert with the great environmental changes that occur during the yearly flood pulse in their native environment. The photo at right shows the two extremes of this variation. The two extremes of peacock bass coloration are so wildly different that they go by separate names (“açu” and “paca” in Brazil and “Speckled” and “3-Bar” peacock bass in the U.S. sportfishing community). Why does this happen?
A recently completed research paper explaining the variability in coloration of Cichla temensis, (the giant peacock bass) was published in “Neotropical Ichthyology”, a peer-reviewed scientific journal. Until then, much of the fishing, management and scientific community believed these variants to be two separate species, or subspecies, or even male and female differences. The new article explains the nature of the color variation and describes the research that led to the new understanding.
The project was undertaken because experienced peacock bass anglers have observed several phenomena that brought the established beliefs into question. First, not only are there two extremes in coloration, but anglers routinely encounter a whole range of intermediate patterns. Furthermore, anglers often catch fish involved in spawning activity, but these are always in the 3-bar form. The earlier existing beliefs failed to explain this. In an effort to answer the questions raised by these observations, the research, performed under the joint auspices of Rutgers University (New Jersey, USA) and The University of Amazonas (Manaus, Brazil), examined the question based on a new hypothesis. Could these variants all be the same fish undergoing seasonal changes related to their spawning behavior?
The project defined several coloration categories or stages (see the photos 1 - 4 in column A in the illustration) to serve as working tools and then examined the problem from three viewpoints. First, it compared fish from each of the color categories to other species of peacock bass that shared the same water, using traditional taxonomic techniques (morphometrics). This confirmed that the variants didn’t belong to any of the other species. Next, the variants were subjected to DNA testing, which showed that they were indeed all members of the same species. Finally, using precise measurements and surgical and photomicrographic techniques, the study showed that these color and pattern variants were actually individual fish changing their coloration cyclically over the course of the Amazon’s yearly rainy and dry seasons. They gradually change from the speckled pattern to the 3-bar pattern as they prepare to spawn during the dry season, remaining in the 3-bar pattern until they finish guarding their babies.
The illustration shows the color and pattern variants as they change from one pattern to another in the four stages defined by the project. Column B shows the ovaries for the each of the stages. As a fish changes from the speckled (paca) to the 3-barred (açu) form, the ovaries enlarge, becoming thicker and fuller in preparation for spawning. By stage 4, they are large and distended. Column C shows photomicrographs of the contents of the ovaries themselves, taken under the microscope. In the speckled stage, immature precursors to eggs (called oocytes) are visible. As a fish progresses through the stages, eggs begin to form and become mature. By stage 2, they begin to show nuclei (containing genetic material). In stage 3, the eggs begin to fill with the yolk that will provide the fry’s first food. The eggs in stage 4 are large and fully mature and ready to be deposited on a submerged wood surface in the peacock’s large nest. The study precisely weighed both ovaries and testes (collectively gonads) of two hundred fish in each of the coloration stages and showed that the mathematical relationship between gonad size and coloration stage is statistically significant. It is the same in both males and females, as is the color change itself.
This new information allows anglers to better understand these fish. For fishermen, this kind of knowledge is power. The better we know our quarry, the more effectively we can pursue and catch it. Scientists know that color can have biological value. Before the spawn, the 3-bar coloration may help spawning fish find partners, saying “Look how beautiful I am, spawn with me!” Later on, like other brightly colored animals, they may be advertising the threat they pose to intruders on their nesting site or to would-be predators of their closely guarded offspring. For example, brightly colored poisonous frogs are warning potential predators not to eat them; the results of that meal could be very bad for the predator. In the same fashion, brilliantly colored, fry-guarding peacock bass parents may be warning other fish to avoid trying to eat their babies; the results could be fatal for the would-be predator. If you’ve ever caught a big peacock under a fry ball with a prop bait, you’ll understand the accuracy of this threat immediately.
At the other color extreme, non-spawning fish are busy going about the business of eating and fattening up for the long fast associated with spawning. They need to hunt effectively in the flooded forests bordering Amazon lagoons and backwaters. If you’ve ever looked into the dark, tea-stained waters at the edge of a lagoon with their submerged wood, dappled with leaf-filtered sunlight, you’ll understand exactly how a dark, speckled predator can disappear into the shadows. Camouflage is a very effective hunting tool.
Most peacocks spawn near the end of the dry season when low water levels make more spawning area available. However, not all spawn at the same time and different spots have different relative depths, so you’ll likely see all of the coloration stages during a typical fishing trip. Now you can observe them with a new perspective. New information also provides scientists with a platform from which to launch future studies - and further research is indeed underway.
The study was performed by, and the article was authored by Paul Reiss of Acute Angling and Rutgers University, with invaluable assistance, guidance and co-authorship provided by Dr. Ken Able of Rutgers and Dr. Tomas Hrbek, Dr. Izeni Farias and Mario Nunez of the University of Amazonas. Funding was primarily provided by Acute Angling, with generous assistance from many of our angling clients who contributed funds for equipment purchases for the study’s jungle laboratory. The journal “Neotropical Ichthyology” can be found online and in print. The article is available in its technical form on our website, here.
Reiss, P., K. W. Able, M. S. Nunes, & T. Hrbek. 2012. Color pattern variation in Cichla temensis (Perciformes: Cichlidae): Resolution based on morphological, molecular, and reproductive data. Neotropical Ichthyology, 10: 59–70.