The Wisconsin mercury advisory recommends that women of childbearing age and children under 15 limit themselves to one meal per week of panfish such as bluegill, crappie, yellow perch and other small species, and one meal per month of walleye, northern pike, bass, catfish and other larger species. Larger, older fish have been shown to accumulate more mercury in their muscle tissues. The advisory also suggests limitations for store-bought fish, including swordfish and canned or fresh tuna.
The thresholds for men and post-menopausal women are more relaxed, allowing unlimited panfish consumption but recommending no more than one meal per week of larger fish species.