The Alagnak River is a tributary of the Kvichak River in the U.S. state of Alaska. It has a catchment area of approximately 1400 square mi (3600 km2). It is located in central Lake and Peninsula Borough. Names According to the National Park Service, in the local language the word Alagnak means "making mistakes". The river course is dynamic, changing often and splitting into new branches. For this reason, it is known locally as the "Branch River", where boaters may mistake one branch for another. On the other hand, Native American Placenames of the United States says that the river's name may come from the Yupik word alagnaq, a kind of red berry. The United States Geological Survey says something similar, citing Richard H. Geoghegan, a philologist, who said the native word referred to a wild raspberry. Course It begins as the outflow of Kukaklek Lake in Katmai National Park and Preserve and meets the sea at Bristol Bay. The beginning of the river lies in the Aleutian Range. The first six miles of the river run slowly through the tundra. Vegetation along the upper part of the river consists mostly of spruce. Afterwards, the valley becomes much narrower with near-vertical rock faces. Miles 7–14 run through a narrow canyon at around 7.5 mph. The Nonvianuk River runs into the Alagnak at around mile 20. To the west, the river meanders over the Alaska Peninsula before flowing into the Kvichak River, which itself flows into Bristol Bay. Flora and fauna Due to the large numbers of salmon, there is a significant bear population in the summer and fall, including both grizzly and black bears. The majority of the catchment area is a winter habitat for Alaskan caribou. Moose are also to be found during the entire year. Along the river, beaver, foxes, wolverines, mink, and otter are all found as well occasional wolf. In the water, there are several varieties of salmon, including sockeye salmon, pink salmon, chum salmon, king salmon, and silver salmon. There are also rainbow trout, char, Arctic grayling, and northern pike. Along the river there is also eclectic vegetation including spruces, willows and various types of berries. History Early history The first humans to arrive at the Alagnak were apparently 14000 years ago, during the glacial retreat of the last ice age. The earliest documented records of humans settling there were 9000 years ago; stone tools