I was interviewed for an article for the Danish Maritime industry about another aspect of shipping and invasive species — hull fouling. The article came out today (in Danish) in a couple formats:
For those not up to reading Danish and too tired to put things in to Google Translate, basically the article is about how ballast water regulation is a big topic at the IMO (International Maritime Organization) and elsewhere while hull fouling, when species hitchhike to new places on the outside of ships’ hulls, is much less discussed – partly because it is harder to regulate and partly because companies’ incentives are already aligned due to cost savings on fuel through reduced hull fouling. Unfortunately most technical solutions such as anti-fouling hulls are both imperfect deterrents and have negative externalities for other marine organisms and water quality. Which is worse is species and ecosystem dependent — due primarily to filters on ballast water intake, different sizes and stages of life are able to travel via ballast water vs. hull fouling. Thus variation in life cycle vulnerabilities will lead to different threats for different ecosystems.
Furthermore, vessels like oil platforms that sit fixed in a location for a period of time may allow transport of more complete ecosystems, which mean higher probabilities of survival for an accompanying invasive species.
The devil really is in the details…