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Gard News 201, February/April 2011

The problem of invasive species being carried around the world by ships is a serious one.

 

 

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In recent years, the issue of invasive species arriving either in ballast water or on the hulls of ships has been a topic of acute interest and regulatory reaction in various countries, and has been the topic of past articles in Gard News.1  Various procedures, permits and standards have been promulgated to deal with the problem, and in some places more are proposed.

The problem is certainly a serious one.  The best known example, where the origin of an invasive species can be pinpointed to a ship, was the incident in 1986 when a vessel bound from a Black Sea port discharged ballast water into Lake Erie, releasing a tiny stowaway, the zebra mussel, which then spread, unhindered by native predator species, to the Hudson River, the Mississippi River, and eventually the Gulf of Mexico, forming large clusters that clogged freshwater intakes, industrial outlets and smaller waterways themselves. These species also kill or render extinct native species, settle on buoys and ships lines, and interfere with aquaculture efforts.

To illustrate this is truly a multilateral problem, the reverse of the above example has also occurred:  a ship from North America, entering the Black Sea, brought there a species of North American comb jellyfish, Mnemiopsis leidyi, which so devastated native plankton stocks that several commercial fisheries in the Black Sea were destroyed, including almost all of the anchovy industry.

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 Zebra mussel.  North American comb jellyfish.

 

Global approach needed
Starting in the 1990s, various national laws and regulations were passed to address the issue of vessels serving as the primary vector of the introduction of invasive nuisance species into exotic ecosystems.  Some of these measures were expensive, time- consuming, and required significant effort, and thus were not welcomed by some in the shipping community.  But after all of that attention and expense, are these actions working to solve the problem?

A recent report issued on 10th June 2010 by the Regional Marine Pollution Emergency Response Centre for the Mediterranean Sea of the United Nations Environment Programme (UNEP)'s Mediterranean Action Plan (MAP)  indicates the problem still exists as a serious phenomenon.  The report states that in the Mediterranean, with 10,000 ships transiting the area every year, commercial vessels currently deposit a new alien species every nine days.

The report suggests that more actions are needed, and that these must be done on an ecosystem-wide basis, and should include not only commercial freight vessels, but also fishing fleets and recreational craft, in order to secure a tighter cordon against the invasion of these pest species. For example, even boots of fishermen on commercial vessels can carry on their treads small numbers of invasive microscopic organisms, that are then remoistened and wash over the side in later fishing activities on deck, thus entering a new ecosystem as an unwelcome visitor.

So, in reaction, on 3rd November 2010 the World Ocean Council, an industry group consisting of shipping, fishing, tourism, and marine environmental companies, called for a renewed push in getting a sufficient number of countries to ratify the Ballast Water Convention approved in 2004.2  The convention requires 30 countries to ratify it in order to come into effect, and so far only 26 have done so, thus it is only four countries shy of entering into force. While individual countries have their own laws in places, it would seem evident from recent studies that a total, world-wide scheme is needed in order to be effective. 

Otherwise, humans will continue to lose the war with these unseen aquatic invaders, posing significant economic risks to marine-related industries, including the world's seafood industry, as well as the desalination of seawater for drinking and the ability of native species to perform their vital roles in keeping a given ecosystem diverse and vibrant.

 

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Basic ballast water exchange and the unintended transport of invasive species.

(Reproduced with permission from IMO/GloBallast). 

 

Further reading
For more information on the spread of invasive aquatic species and measures being taken for its reduction readers should refer to the article "Setting a Course for Ballast Water Management - Reducing the gloabal spread of aquatic nuisance species", by John Morris, Environmental Protection Specialisit, US Coast Guard Office of Operating and Environmental Standards at http://www.uscg.mil/proceedings/Winter2010-11/Winter_2010-11.pdf.

Footnotes
1 See articles: "More on unwanted aquatic organisms in ballast water - All ships are now potential polluters" in Gard News issue No. 155; "California - Ballast Water Regulations" in Gard News issue No. 157; "Unwanted aquatic organisms in ballast water - New requirements in Australia" in Gard News issue No. 163; "Control and management of ballast water - Recent developments" in Gard News issue No. 173; "New ballast water regulations in force in Brazil" in Gard News issue No. 181; "Ballast water - Victoria, Australia" in Gard News issue No. 183; "Ballast water - Peru" in Gard News issue No. 183; "Carp(e) diem - Current issues on ballast water regulations in the US" in Gard News issue No. 198; and "Norway - Ballast water regulation" in Gard News issue No. 199.
2 See article "Ballast Water Convention adopted" in Gard News issue No. 175.