There are a number of lampreys common to North America and its surrounding waters. Most species
of lamprey are not parasitic. All lampreys spend the first four years of their lives, during which they are known as
amoecetes larvae, living as filter feeders buried in the mud at the mouth of small streams and rivers. Eventually they
metamorphose, or change, into the adult form. The lamprey shown here is facing forward with its mouth completely open.
