Weighting as much as 400 pounds, the massive arapaima fish is likely one of the largest fish you could ever see with your own two eyes. However, time is running out to see this majestic behemoth. Researchers have learned that the fish has become extinct in many local communities simply due to overfishing.

Researcher Leandro Castello is an expert of fisheries. According to him, the main problem for the arapaima fish is that it's just too easy to catch. With populations growing and the fishing industry finally reaching Amazon villages, these massive fish are being swept out of local waters until none are left.

Castello authored a study on arapaima populations in the journal Aquatic Conservation: Freshwater and Marine Ecosystems.

"Bioeconomic thinking has predicted that scarcity would drive up fishing costs, which would increase price and help save depleted species," Castello said in a recent statement. "If that prediction were true, extinctions induced by fishing would not exist, but that is not what has happened."

According to the study, the massive 10-foot-long fish spawns at the edges of flood plains, and tends to swim close to the surface of these relatively shallow waters. This makes them easy to find and harpoon even for non-commercial fishermen with homemade canoes.

There were five known species of arapaima in the Amazon, but three of these five haven't been seen for decades.

After surveying 81 Amazon fishing communities and interviewing 182 local fisherman, the researchers found that arapaima populations disappeared and were likely extinct in 19 percent of these communities.

To worsen the problem, the research team has found that even after adult arapaima are fished to extinction, juveniles are unintentionally getting caught in gill nets as the communities attempt to switch to smaller fish.

Still, it's not all bad news. The study also details how some communities are learning about conservation, with 27 percent of the communities surveyed creating managment rules for fishing the arapaima.

"Many previously overexploited arapaima populations are now booming due to good management," Castello added. "The time has come to apply fishers' ecological knowledge to assess populations, document practices and trends, and solve fisheries problems through user participation in management and conservation."