Originally Posted by JeanneP' date='16 April 2010 - 12:56 AM
None of this is to argue against controls against bio-fouling, but I believe Australia's focus on private yachts is an expensive imposition (AUD $250 an hour? That's about twice the markup that is placed on retail goods for sale!) when it is the commercial ships speeding across temperature and time zones that are the major culprits, and about which nothing is yet done. Private yachts generally do not carry, nor expel, ballast water which have been the identified source of some of the worst pest introductions, including zebra mussels, comb jellies, the european green crab, and sea stars. When one looks at the size of the commercial ships, and their numbers entering the harbors of the world, to expend significant resources to control recreational vessels' questionable source of biofouling but not the commercial ships, seems to me to be little more than a stage show that accomplishes little, if anything at all.
I would agree fully that AUD$250 an hour is a bit pricey! As I am going to be sailing to Aus from NZ in a few months I expect that I will be a bit grumpy at the cost when we get into Brisbane.
I also agree that commercial vessels pose an obvious risk- they dont get off scott-free though. Ballast water regs being as they are now there are costs they carry. I know of a big chemical carrier that was coming into the Port of Vancouver a few years ago that had not exchanged its ballast water at sea and was arriving from a designated risk area. It was to be turned away from port but the weather was bad (solas comes before pests) so the port let it in but not before they had their ballast water sterilised by independent experts (the company I work for!) at a cost to the vessel operator of about $30k.
No question though that we could do more and international negotiations are underway to do just that. I do re-iterate though that recreational yachts are a major risk, however (not my boat-home, of course!!). A project in NZ recently looked at trying to assess the risk of rec yachts by assessing from the surface. Basically the team made an estimate of fouling from the surface then followed that up by diving on the yacht and making a quantitative assessment (including identifications of critters scraped off) of the fouling actually on the wetted area. There was (no surprise) a pretty strong relationship between those yachts that were obviously fouled from the surface with what was below. But (and this is a big but), several fairly nasty hitchhikers were present on yachts that looked really good from the surface <<sigh>>.... so basically there was no bomb-proof message to take away from the study. Similar work in oz has revealed much the same thing.
The black striped mussel (BSM) problem in Darwin in 99 emphasised that small boats do play a big role in transmitting marine pests. That cleanup cost $3million and it was due to small boats bringing in BSM. I was chatting with a dive inspector for AFMA (aussie fisheries management agency) in Darwin yesterday about how they found BSM, asian bag mussels and green mussels on a single boat trying to get to Australia just last week. Their response is to quarantine the boat well offshore, wrap the wetted surface in a bag and fill it with a chlorine solution for a couple of days!! When everything is dead they let it out. That is at no cost to the vessel owner.. unless of course they are illegally fishing or people smuggling, in which case they just bring the now sterilized boat to shore and torch it!!
Sorry I am nattering on again a bit- it's a fascinating topic (at least to us science geeks!)