Both reservoirs are in the eastern part of the state, with Gartside situated a stone’s throw from the Yellowstone River near the North Dakota state line. The reservoir also holds largemouth and smallmouth bass, as well as bluegills, walleyes, and pike.
Green sunfish are an introduced (non-native) species in Montana, according to FWP. They can be found throughout the lower Yellowstone and Little Missouri drainages, where they are “well suited to radically changing conditions found in prairie streams.” The species’ native range stretches from the Great Lakes down to Mexico, and includes all of the Central Plains west of the Appalachian Mountains and east of the Rocky Mountains.
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