Aniakchak National Monument and Preserve provides unusual and dramatic landscapes shaped by numerous volcanic eruptions, a massive flood, enormous landslides, and ongoing geological change. The focal point of the monument is Aniakchak Caldera, a restless volcano that embodies the instability of the Alaska Peninsula. This geological instability creates a dynamic and challenging environment for the biological occupants of Aniakchak and unparalleled opportunities for scientists to measure the adaptability of organisms and ecosystems to change. The sockeye salmon (Oncorhynchus nerka) is one member of the Aniakchak ecosystem that has managed to adapt to geologic upheaval and is now thriving in the park. Aside from just surviving in the harsh environment, these salmon are also noteworthy for providing essential marinederived nutrients to plants and animals and as a source of food for historic and present day people in the region.