Ballast Water & Invasive Species

The globalization of trade, and the advent of larger and faster ships have increased the likelihood of species transfer.

The introduction of invasive marine species from ballast water into new environments is a major threat to the earth's oceans and waterways and is a major international concern for environmental, health, and economic reasons. The globalization of trade, and the advent of larger and faster ships have increased the likelihood of species transfer. Regulations established by the 2004 International Convention for the Control of Ships' Ballast Water and Sediments will require the treatment of ballast water on ships to address the problem.

There are thousands of invasive aquatic species transferred around the world in ballast water every day. Below are a few examples noted by the International Maritime Organization1.

    • Aquatic Species:

      North American Comb Jelly (Mnemiopsis leidy)
    • Native to:

      Eastern Seaboard of the Americas
    • Introduced to:

      Black, Azov and Caspian Seas
    • Impact:

      Contributed to collapse of Black and Asov Sea fisheries in 1990s, with significant economic and social impact.
    • Aquatic Species:

      Round Goby (Neogolus melanosromus)2
    • Native to:

      Black, Asov and Caspian Seas
    • Introduced to:

      Baltic Sea, North America
    • Impact:

      Competes with native species for food and habitat.
    • Aquatic Species:

      Toxic algae (Red/Brown/Green Tides) various species
    • Native to:

      Various species with broad ranges
    • Introduced to:

      Several species have been transferred to new areas in ships' ballast water
    • Impact:

      May form harmful algae blooms. Depending on the species, can cause massive kills of marine life through oxygen depletion, release of toxins and/or mucus. Can foul beaches and impact tourism and recreation. Some species may contaminate filter-feeding shellfish and cause fisheries to be closed. Consumption of contaminated shellfish by humans may cause severe illness and death.
    • Aquatic Species:

      Zebra Mussel (Dreissena polymorpha)
    • Native to:

      Eastern Europe (Black Sea)
    • Introduced to:

      Western and northern Europe, including Ireland and Baltic Sea and the eastern half of North America
    • Impact:

      Fouls all available hard surfaces and displaces native aquatic life. Blocks water intake pipes, sluices and irrigation ditches. Economic costs to USA alone estimated to be US$750 million to $1 billion between 1989 and 2000.
    • Aquatic Species:

      European Green Crab (Carcinus maenus)3
    • Native to:

      European Atlantic Coast
    • Introduced to:

      Southern Australia, South Africa, the United States and Japan
    • Impact:

      Highly adaptable and invasive. Competes with and displaces native crabs and becomes a dominant species in invaded areas. Consumes and depletes wide range of species.

1 Used with permission, reference: http://globallast.imo.org/poster4_english.pdf, ©2002, International Maritime Organization
2 Photo used with permission of Michigan Sea Grant
3 Carcinus maenas. Photo by Hans Hillewaert on board of RV Belgica at Westdiep on 28/09/2005. From Wikimedia Commons: http://en.wikipedia.org/wiki/File:Carcinus_maenas.jpg. This file is licensed under the Creative Commons Attribution-Share Alike 2.5 Generic license: http://creativecommons.org/licenses/by-sa/2.5/deed.en