Arapaima

The Arapaima (Arapaima gigas) is one of the largest freshwater fish in the world. Measuring up to ten feet long and weighing 400 pounds, it is a true river giant. They are native to the Amazon River, where they and their descendants have been swimming since the Jurassic.

Arapaimas are air-breathers, meaning that they inhale their oxygen through the air rather than through the water. Because of this, they are typically found near the surface of the water, though they are able to hold their breath for 10-20 minutes.

The breeding cycle of the Arapaima is dependent on the seasons. Eggs are laid February-April, when the water is at its lowest, and hatch during the flooding season so that the young fish can thrive and feast on all of the organisms that are churned up. Male Arapaimas take an interesting role in the process, incubating the eggs in his mouth (mouthbrooding).

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Water birds beware! Though the Arapaima mainly eatsfish, they will also gulp up birds that they find on the waters' surface. Surface proximity has caused problems for the Arapaima; it makes them much easier to fish for with nets or harpoons. Their meat, tongue, and scales are collected for food and jewelry. Hunting has been the main reason for their population decline, and they are now listed as Vulnerable.