Stuff.co.nz is reporting that the New Zealand government is using strong measures to deal with the potential introduction of the brown mussel (Perna perna) into Tasman Bay. The response stems from a incident in late 2007 where an oil rig relocated to the bay in order to "defoul" (cleanse itself of unwanted organisms). The rig got clearance from the Ministry of Agriculture and Forestry Biosecurity New Zealand (MAFBNZ) after initial inspections failed to reveal any species that New Zealand considered to be a problem. However, bad weather kept the rig closer to shore than expected, and further testing revealed the hull may have been contaminated with the invasive mussels. When the government sent robotic cameras under water to investigate, they detected what appeared to be brown mussels living at the site where the rig was located. While the exact species of mussel still needs to be confirmed, MAFBNZ is moving forward this week with a dredging of the area of Tasman Bay thought to be impacted, and the rig's owners are footing most of the bill.