Lamprey-09-Doug OwenSea Lamprey

Sea lampreys have been one of the most devastating invasive species to enter the Great Lakes. Over time, they’ve contributed to the decline of native fish populations and threaten a multi-billion dollar fishing industry. Using the sea lamprey as an example, this lesson explores how harmful non-native species can be and how expensive and complex it is to control an invasive species once it is established.

Grade level: 4-8 grades

Performance Expectations:

  • MS-ETS1-1 Engineering Design: Evaluate competing design solutions using a systematic process to determine how well they meet the criteria and constraints of the problem.
  • MS-LS2-5 Ecosystems: Interactions, Energy and Dynamics: Evaluate competing design solutions for maintaining biodiversity and ecosystem services.

For alignment, see: Sea Lamprey NGSS Summary


  • Discuss the differences among the various types of technology used to control the sea lamprey population.
  • Locate the lamprey-associated, spawning ground “hot spots” in the Great Lakes.
  • Describe parasite/host relationships.
  • Identify the placement of the Great Lakes and describe how the lakes are connected.


sea-lamprey mouths seen from an aquariumSea lampreys are eel-like fish that are native to the Atlantic Ocean. Since the 1830s, they have been migrating into the Great Lakes via Lake Ontario and the Erie Canal. Niagara Falls acted as a natural barrier for sea lampreys until the Welland Canal was improved in 1919. Once sea lampreys entered Lake Erie, they quickly spread to Lake Huron and Lake Michigan. In 1938, sea lampreys entered Lake Superior. Because sea lampreys attach to and feed on native freshwater fish, they have posed a serious threat to whitefish, lake trout and salmon during the past 50 years.

A single lamprey is capable of consuming 40 pounds of host fish in its lifetime. During a lamprey’s 18-month span as an adult, it will attach to a host fish with its suction-like toothed mouth, then suck nutrition out of the host fish, often killing it. The rapid decline in the number of native freshwater fish affects a Great Lakes sport and commercial fishing industry valued at almost $4.5 billion annually.

Biologists use a combination of methods to control the sea lamprey population in the Great Lakes. Several types of mechanical and electrical barriers have been constructed in strategic locations on Great Lakes tributaries. The barriers allow native freshwater fish to migrate upstream but block sea lampreys from reaching spawning habitat. Sterilization programs for male sea lampreys have also reduced the sea lamprey population. A special chemical that kills sea lamprey larvae, and an underwater high-power vacuum have both been used in the St. Marys River lamprey spawning grounds to eliminate thousands of lamprey larvae.



  • Break the Barriers
    Summary: This board game teaches students about the various methods used to limit the sea lamprey population in the Great Lakes. Students assume the identity of sea lampreys and attempt to migrate from Lake Ontario to Lake Superior.
    Time: 15-20 minutes