Razzonater said..
Any historians amongst us or perhaps those of a rupee vintage than me may have a first hand account but.......
A few nuns went for a swim at trigg, they got dragged out towards the point to where the "blue hole " is or was,, several of them drowned..
I think prior to this there may have been a few other singular drownings of younger people and swimmers...
This was however the last straw, they blew the "blue hole" area of the reef to smithereeens and from what I have heard took a huge chunk out of the reef and displaced the current quite significantly.
I would be interested if anyone has a link or proper recount of this story especially any photos prior and after..
I am quite certain this is a true story and not folklore
I started fishing Trigg in the early 90's when i was 11 or 12 and up untill maybe 2003 i fished that area most days before school, after school, on weekends, around study, work etc and annoyed the **** outta poor old Cleggie

. When you talk about Trigg in the 80's and 90's he was certainly part of it all and he passed about 10 years ago now and even with his issues he was always good to me and i never once heard him swear! I still dont understand how people can have a nice boat and bother with bloody whiting though!!
I used to keep my tripod under the bushes at Ron's(?) house in the carpark (i wonder if its still there but what a $$$ location) and while that kept me dry i much preferred being mobile while fishing on the reef. Getting bashed around a little or stepping in a hole at 4.30am is better than getting knocked off your tripod. I caught and released a lot of fish from that area and even got a 5.5kg tailor one day. Back then it was good fishing for Perth metro which was already flogged to death.
The old blokes on tripods had plenty of stories of the 70's and 80's and a few people did drown so it was blown up but i was always told the reef was made out to be more dangerous than it was and bad swimmers just got into trouble. I was also told that the nun died at what was known as nun's pool to the north and not the blue hole itself.
There was/is kind of 2 "blue holes" still, depending on the season or the beach in winter and while the current and water movement back out can be really strong it's not so bad in summer. That being said, one of the guys i fished with found a body on/under the reef one morning in the late 90's but he had gone missing from further south.
On calm evenings i used to snorkel there to collect all the lost lures

and in all the years i fished that area i only saw the island as an actual island twice. Maybe times have changed, fishing Trigg was such a huge part of my life growing up but i dont think i've been back in 10+ years.
Edit: You can see how the reef has changed from this googled pic from 1970. The blue hole itself is on the left but you can still see a bit of it today and thats where we fished in summer but closer to the beach is another shallower hole that the water channels out. There is/was a platform of rock that used to get exposed some winters and you fished into the that "hole". I think that was part of the rock in the foreground of the island? The tailor were always bigger in winter, 2-4kg fish weren't uncommon but cable station used to see the odd 6kg+ fish but it was too far for me to ride!