Exam Question

(a) The need for such a convention
Globally, it is estimated that about 10 billion tonnes of ballast water is transferred each year. The water taken onboard for ballasting may contain aquatic organisms, including dormant stages of microscopic toxic aquatic plants , which can cause harmful algal blooms upon release. Additionally, pathogens such as bacteria have been transported with ballast water.
As ships now travel faster, the survival rate of species carried in ballast tanks has increased. Studies show that many species of bacteria, plants, and animals can survive in ballast water even after journeys lasting several months .
As a result, non-indigenous organisms have often been introduced into new environments, sometimes with disastrous consequences for the local ecosystem , including the destruction of important fish stocks or rare species .