mathew forum posts in last 60 days

AoetearoaSailor said..

John340 said..

mathew said..
While on the subject of sharks....

Drum-lines... what the ?! ... all they do is _attract_ sharks, because they are baited. Putting them 500m offshore is just stupid. 10km maybe... dont put them close enough to bring the bigger predators closer to the shore.

Shark-nets... there is no definitive evidence that they work (how do you prove a negative?), and plenty of evidence they dont work (shark-bites inshore of the net).

Matt,
There has been one fatality and a handful of serious injuries on netted beaches due to shark attacks in NSW since netting begun ,90 years ago. There have been roughly 150 fatalities on un netted beaches in NSW since records began.It would appear based on these stats that while netting may not reduce all unprovoked shark interactions they have a significant effect in reducing fatalities.

Haha.. as an ecologist - and very much playing devil's advocate here..

It *could* be that the unnetted beaches are simply where most of the sharks live now. Looking at the NSW shark net map:
www.sharksmart.nsw.gov.au/__data/assets/pdf_file/0020/1240814/nsw-shark-program-2020-21-map.pdf
All the shark net beaches are concentrated around the Sydney area. This area of the coast could also be less attractive to sharks - due to for example a greater density of marine traffic scaring them off, or perhaps less food sources including seals (then again, there might be more seals, if there's less sharks), etc., which could explain the relative lack of attacks concentrated around the Sydney area.
Against this, you'd then have to weigh up the higher statistical probability of shark encounters due to more total person-hours in the water, which presumably is higher in the Sydney area - so on this basis you'd expect a counter greater frequency of attacks in this area.
As an ecological experiment - it is very poorly designed, haha.. and it might be difficult to test statistically.

100% this. The nets are where the people are. Most shark-bites occur where there aren't nets. ergo, hard to attribute success due to the number of variables. But easy to attest failure.

As it turns out, there may be a tech solution to replace shark-nets that may work to some degree. ( It isn't drones, although that is an interesting idea as well.) It would be significantly cheaper to install, requires no regular human intervention or maintenance... thus can be more widely deployed.

OES are awesome supporters of the WaveRally.

If you turn up to Coronation Beach during the competition you can try out their boards. Then you dont need to guess !

The support-page has a picture of a scuba-diver. Every scuba-diver _wants to see_ sharks in the wild... we definitely dont want to scare them away. There is a phrase "Divers have too much money" and it exists because divers regularly go to holiday destinations... to see sharks (and obviously other big fish).

No scuba-diver will support such a plea, so if this isn't a scam website, then that pic probably should be removed.

The biggest issue with 3+3 people (or more... I have seen 3+3+booms, 5+5, etc) or the car+tree, is that you _are_ likely to separate the two halves, at least to some degree.

But the joint heats up ... a lot... which will cause an sheer-weld using the epoxy. This is typically called galling (frictional heating).

You need to keep the joint cool, or you need to not-stop-moving once the joint starts separating.

Great to see Narrow Neck being sailed in windy conditions.
Was there much sweep on the beach ?

Just thought I would post a message to show that the 80's are still in vogue - go for a sail in the Whitsundays, and windsurf in the white sands of Whitehaven Beach.... a few friends decided to hire a catamaran for 5 days.

After a 4hr briefing, we set out from Airlie Beach. Sailed out to Langford Island Reef on the first day - was blowing 22kn most of the way, which made for a an 8+kn cruise across the wind. Got there a bit late in the arvo, and being the first day on a new boat, we missed the timeslot for a windsurf. Some of the passengers got their first taste of forgetting-to-take-TravelCalm !

The next day we headed off to Whitehaven Beach... the pics from the 80's kept us calling. Got there just after lunchtime. Some of us had a good session in the clear water and white sand. Wind speed was at 18kn.

The third day had 16kn, so bigger gear.... but very fun !

4th day was about 8kn, so a swim and snorkel. Then a downwind cat-sail back to the inner side of the islands.

5th day back in the marina.

It was a good test for the viability of such a cruise. The skipper has sailed across the Atlantic Ocean, but that was 20yrs ago in a mono-hull. Rigging the gear on the deck, turned out to be easier than expected; connecting/disconnecting the mast-base, was harder than expected. Anchoring up in the wind, needs a lot of practise and a lot of patience. And then there is the logistics of getting everything on board, setting used to stocking the food for a week, etc.