The Burrishoole traps (on the Salmon leap and the Mill race) in Co. Mayo Ireland, capture every fish that migrates between the freshwater portion of the Burrishoole catchment and the sea, and are situated between Lough Feeagh and Lough Furnace. The traps are emptied every day, and fish are manually counted and released downstream or upstream. This dataset comprises the daily counts of salmon (Salmo salar), trout (Salmo trutta) and silver eel (Anguilla anguilla) from 1970 to 2020. Data have undergone QA/QC and checked for erroneous entries. More recent data can be requested or downloaded from the Marine Institute through www.marine.ie. Additional information can be obtained from burrishooleLTER@marine.ie The Burrishoole fish traps have the following locations: Salmon leap: 53.920323, -9.584348 and Mill Race: 53.924081, -9.571727. Suggested Citation: Rogan, Ger; French, Andrew; Poole, Russell; Kelly, Sean; Cooney, Joseph; de Eyto, Elvira; Dillane, Mary; Drumm, Alan; Hughes, Pat; Maxwell, Hugo; Murphy, Michael; Nixon, Pat; Sweeney, David. (2021) Daily counts of migration of Atlantic salmon (Salmo salar), trout (Salmo trutta) and European eel (Anguilla anguilla) in and out of the Burrishoole traps, Co. Mayo, Ireland, 1970-2020. Marine Institute, Ireland. doi:10/fq6z.