Adults inhabits coastal and estuarine waters (Ref. 59043). Prefer sites with stony or sandy bottom, shaded by riparian vegetation (Ref. 41072). Spawning adults found in gravel riffles and runs of clear streams; feeding adults usually in oceans or lakes; ammocoetes in muddy margins and backwaters of river and lakes (Ref. 5723). Anadromous (Ref. 58426). There are non-migratory freshwater populations. Probably parasitizes any species of fish of suitable size (Ref. 27547), including commercial species (Ref. 58426). Subadults are non-parasitic (Ref. 12218). Feed on small aquatic invertebrates, algae and organic matter contained in detritus (Ref. 41072). Arctic lamprey has high quality flesh rich in fat (Ref. 41072).