New Kids on the Freshwater Block

Until recently, the Aquarium has been using one particularly flashy and popular fish as the spokesman for Project Piaba—the cardinal tetra.

Cardinal tetra | Photo by Lerdsuwa via Wikimedia Commons

The lifecycle of these fish fluctuates on population booms and busts according to the wet season/dry season in the Amazon. Locals around the town of Barcelos harvest these fish for the aquarium trade in a low-impact sustainable way. This trade provides valuable income to the region, which in turn provides incentive to the residents to preserve the rainforest that supports these fisheries.

Besides the massive anaconda in the exhibit, you'll also find fish
of many different sizes in the anaconda exhibit.

Did you know that many other Amazonian fish are also harvested in the same way? Learn more about this counter-intuitive conservation effort in this piece from Discover Magazine, which features senior aquarist Scott Dowd.

Now let's meet a couple other species currently on exhibit in the anaconda display of the Amazon Rainforest exhibits. This exhibit is now teeming with beautiful fish and an important conservation message: Responsible fisheries are an important way to help protect our blue planet.

Discus get their common name from their flat, round body shape which resembles the heavy disc thrown in track and field. Like most cichlids, they exhibit parental care, with both parents assisting with the young. The male and female adult discus both produce a secretion through their skin which the larvae live off- almost like nursing their young!

A discus, with those flashy neon tetras in the background. Photo via Instagram

Twig catfish (Farlowella)
These fish get their name from their elongated twig-like appearance. We have several in the Anaconda exhibit that can usually be found right upfront sticking against the glass. Like otocinclus, which you'll learn about below, they are algae eaters to earn their keep.

You'll often find the twig catfish stuck to the smooth glass surface of the tank.

Now see if you can recognize some of the fish in this video:

Marbled hatchetfish
These fish get their name because their body resembles the head of a hatchet. Their family name Gasteropelecus actually means hatchet-shaped belly. The hatchetfish’s claim to fame is that they can leap from the water and seem to fly through the air, pumping their large pectoral fins to catch flying insects. They are generally accepted as being the only true flying fish. There are a number of fish that can leap out of the water, but only these freshwater hatchetfish actually use their pectoral fins to aid in their flight. Hatchets usually occupy the top portion of the tank, and because they will not swim to the bottom to eat, all of their food must float.

Otocinclus are a type of armored catfishes, and are commonly called "dwarf suckers" or "otos". They are popular aquarium fish, and are often used as algae eaters. Unlike most catfish, otos like company and live in schools. Their claim to fame is that they have a special adaptation at the junction of their esophagus and stomach that allows them to breathe air!

Splash tetra
Splash tetras are unique among fishes in that they lay their eggs out of water. The male positions himself beneath overhanging vegetation growing beside the river and puts on displays for passing females. When a female sees something she likes, she positions herself next to the male and the two leap out of the water together, attaching themselves to the bottom of a leaf by their fins. The pair then lay and fertilize their eggs before falling back into the river. Once the egg mass is complete, the male positions himself in the water under the leaves, watching the egg and occasionally splashing the eggs with his tail to keep them moist, which is how they get the name splashing tetra. Once the eggs hatch, the fry fall into the water and swim for cover.

Three Spot Earth Eater
Found near the bottom of the anaconda exhibit, these cichlids are bottom feeders who suck up gravel to sift for food, and then spit it back out. Their Latin name, however, is much more sinister—Satanoperca acuticeps—which compares them to Satan! Earthmover cichlids are mouth brooders, with the fathers sheltering the fry in their mouths (just like the Banggai cardinalfish). People in the Amazon noticed this unusual behavior and immediately compared it with a local mythological demon that slurps up her own children and then vomits them out.

So now that you know these fishes' amazing stories, head over to the anaconda or flooded Amazon exhibits. , tell these fishes’ amazing stories, and most importantly, how they are harvested and where they come from.

Buy a fish, save a tree!

This information was prepared by Aquarium educator Lindsay Jordan. Look for Lindsay and other Aquarium educators near the exhibits and come armed with lots of questions. They'll be able to answer those questions and share information about many other exhibits throughout the building!


  1. Sustainable fishing is such an important concept and critical to the long-term success of these awesome fish. Thanks for your leadership here.

    1. Al, we greatly appreciate your interest and support. Our conservation department also does a lot of work with sustainable fishing that you might be interested in, too. Here's a link: http://www.neaq.org/conservation_and_research/projects/fisheries_bycatch_aquaculture/index.php

  2. I love the aquariums amazon exhibit it is probably my favorite. Of course, I love the aquarium in general, but the amazon is somewhere I have always wanted to go. This is because I love to help endangered animals and the amazon is full of them.
    resgatar o amazonas!