"Arbokhan Arbosinov is in his element on the water. Lake Balkash is his home. "Balkash is a lake. We call it the sea." Arbosinov is a fisherman, one of hundreds who depend on these waters. Balkash lies in Kazakhstan and is one of Asia's largest lakes. But now its existence（存在） is acutely（强烈地） threatened（威胁） and with it the livelihoods of more than 3 million people who live in the Balkash basin. "Life without Balkash is not life. We need the lake."

  The day begins early for the fishing communities of Lake Balkash. They have to check all the nets before it gets hot. "We're flying." Balkash is distinctive（有特色的）. Part of the lake is fresh water and part salt water. This treasure（财富） of southeastern（东南方的） Kazakhstan is 600 kilometers long and 70 kilometers wide with an average depth（[海洋] 深度） of around 6 meters.

  "Balkash keeps us alive." For more than 20 years, Arbosinov has earned his living by fishing on Lake Balkash. He has a license for a specific fishing area. He works there together with a few colleagues. They're allowed to catch up to 100 tons（吨） of fish a year. "Fishing is hard work and sometimes it's very dangerous. You can even drown（淹死）.

  There are dangerous winds here and waves up to 2 meters high. I've been caught in a storm three times. It was terrible. I barely（几乎不） made it to shore（滨）." Today the weather is calm. Ideal（理想） for fishing.

  But Arbosinov says that fishing away from the shore requires good boats with powerful engines. It's much more complicated（复杂的） and it costs money. Money that the fishermen here often don't have. That's why they mostly ply their trade along the coast. Arbosinov checks today's catch（捕捉）. "How's it going? How much did you catch?

  Not much." This isn't the first time that the fishermen of Balkash have come home with nearly empty boats. One of the reasons they have so little yield（产量） is the snakehead fish. Arbosinov says it suddenly started appearing in these waters a few years ago. "The snakehead eats all the other fish. They're afraid of him. Soon there will be only one fish in the whole Balkash lake, this snakehead."

  The snakehead is a super（特级的） predator（掠夺者） that has no natural predator（掠夺者） in the lake. The people of Balkash are certain the fish didn't end up here naturally. One theory is that it was brought here from a zoo in Moscow. If true, it would mean that humans have altered（改变） the Lake Balkash ecosystem. Besides（而且prep除…之外） other fish, Balkash snakeheads eat frogs, young birds and even muskrats. But Lake Balkash faces a much bigger problem than a mere（仅仅） predator（掠夺者）.