Berlin Reservoir, Lake Milton, and Walborn Reservoir are three bodies of water within the Mahoning River watershed in Northeast Ohio. This IBA exists as a result of the shoreline and mudflats surrounding these reservoirs when drawn down. The Mahoning River flows north through the Berlin Reservoir and Lake Milton, with Walborn Reservoir to the west on Deer Creek, a tributary of the Mahoning. The U.S. Army Corps of Engineers constructed Berlin Lake in 1942 with a minimum pool of approximately 3,600 acres. Lake Milton was constructed in 1916 by the City of Youngstown with water covering approximately 1,700 acres. The Walborn Reservoir, owned by the city of Alliance, was finished in 1971 with water coverage of approximately 700 acres. Starting in mid-summer pools are drawn down, resulting in hundreds of acres of extensive mudflats. The combined potential of mudflats during the fall low-water season is more than 2,000 acres. Surrounding Berlin Lake is 6,800 acres of land owned and managed by the Ohio Department of Natural Resources.

Exposed mudflats at these reservoirs have demonstrated an attraction for numbers and diversity of shorebirds at times rivaling any Lake Erie site and matching Hoover Reservoir in Delaware County for an inland site. It remains fairly consistent for an inland site although there are large areas with little forage for shorebirds. Species recorded include American Golden-Plover, Black-bellied Plover, Killdeer, Semipalmated Plover, American Avocet, Greater Yellowlegs, Lesser Yellowlegs, Solitary Sandpiper, Spotted Sandpiper, Hudsonian Godwit, Marbled Godwit, Ruddy Turnstone, Sanderling, Stilt Sandpiper, Pectoral Sandpiper, Western Sandpiper, White-rumped Sandpiper, Least Sandpiper, Semipalmated Sandpiper, Baird’s Sandpiper, Buff-breasted Sandpiper, Short-billed Dowitcher, Long-billed Dowitcher, Wilson’s Snipe, American Woodcock, Wilson’s Phalarope, and Red-necked Phalarope.