The same questions and claims regularly come up when talking about ballast water and its treatment. “Ballast water has been transported ever since ships were invented”, or “The invasive species have already been transported so the problem won’t get any worse”, or “There were no problems yesterday, why would there be any today”. Despite being rather common claims, they are not accurate. Here is why.
Before water, the ballast used on ships was actually solid, i.e. rocks and sand. The fact that water is used nowadays has much to do with the invention of pumps, which made the whole system viable.
One may ask why ballast water is such a big issue now? Was it safer years ago? In the past, ballast water was in some cases carried in oily tanks, which meant that living organisms didn’t survive. The only problem is that it caused oil pollution, so not a perfect fix.
Shorter voyages equal higher survival rates for invasive species
Rapidly growing international trade has led to vast increases in marine traffic. The Suez and Panama canals have cut the length of voyages dramatically. The downside of these shortened voyages is that invasive species have a higher probability of surviving the shorter periods spent in ballast tanks.
Unlike oil spills, the damage caused by invasive species is enhanced over time. In fact, the damage caused by invasive species may by irreparable and entirely uncontrollable. In the Great Lakes the spread of the zebra mussel, for example, has led to financial damages to the tune of hundreds of millions of US Dollars. Like an incurable disease, we are left to treat only the symptoms while the actual problem and cause is here to stay.
Zebra Mussels are one of the “ten most unwanted” and have become an invasive species in many countries around the world. They disrupt ecosystems and damage harbors, waterways, ships and boats as well as water treatment and power plants.
Prevention is better than cure
The best medicine for invasive species is to prevent them from spreading in the first place. The problem has not been solved. Every year new invasive species are introduced to new areas across the globe. Some species may be harmless, but other pose serious threats to human health, local business and the environment.