The weight of a lamprey can vary greatly depending on the species and its size. Generally, smaller species weigh only a few ounces, while larger species can weigh several pounds. For example:
- The American Brook Lamprey (Lampetra appendix), often used for fishing bait, typically weighs less than 1 ounce (28 grams).
- The European River Lamprey (Lampetra fluviatilis), a smaller parasitic species, typically weighs around 1 ounce (28 grams), with individuals reaching up to 2 ounces (57 grams).
- The Sea Lamprey (Petromyzon marinus), a larger parasitic species, can weigh significantly more. Adults typically weigh between 1 and 3 pounds (0.45 to 1.36 kilograms), but some individuals can weigh up to 5 pounds (2.27 kilograms).
It's worth noting that the weight range provided here is approximate, and the exact weight of a lamprey will depend on its specific species and individual variations.