CalCOFI conducts seasonal, quarterly cruises off southern & central California from nearshore to ~400nm offshore. The 70yr old program & time-series originally sailed monthly, surveying the entire California coastline with multiple ships. Since 1984, when the current 75 station pattern was established using a single ship. The quarterly cruises are scheduled within these desired start & end date windows. Winter & Spring cruises are typically longer & include stations north of Pt Conception.