I used to trick animals on to sharpened hooks. Sometimes, I’d use two or three just to make sure they couldn’t get away.

The hooks would cut their mouths open and, more often than you’d think, pierce them somewhere on the face, even in the eyes. I didn’t even do it to eat. Like millions of others, I did it for “fun”.

If I had done these things to a dog or a cat, people would want me in jail. But here I am, talking about fish. “Fish have no pain receptors”, they say. “Don’t worry, they’re too stupid to understand.”

Play Video Watch as a massive hammerhead shark chomps through a whaler shark which had been caught off Exmouth by Peak Sportfishing’s Wes Jones. The West Australian Video Watch as a massive hammerhead shark chomps through a whaler shark which had been caught off Exmouth by Peak Sportfishing’s Wes Jones.

I believed it all, especially since it came from the mouths of family members and friends.

The fish on the end of my line would try unsuccessfully to swim for their lives as I dragged them in. Suffocating and terrified, they would thrash about while I took my time removing hooks (sometimes even standing on the fish to keep them still), organising other lines and finding my camera for that all-important photo.

I knew the animal in my hands could only breathe underwater, but I wanted to show my buddies what I’d been up to. Hooks often don’t come out how we’d all like to say they do — sometimes they pass the lips and move down the throat. But don’t worry: once I was done, I’d throw the fish back in the water — dead or alive. That’s “catch and release” ... isn’t it?

The “release” is the part where you feel like a real nice guy. You might say, “There you go, mate”, as if you’d just done them some kind of favour. Sometimes, when I threw them back, I saw them hit a rock on the way down. But then I’d just thread another piece of bait on to the bloodied hook, throw it back out into the water, and say, “Next time, I want a bigger one”.

I did this for 10 years, until one day in Perth, I held in my hands one of the prettiest fish I’d ever seen. He was scared and oxygen-deprived, and I’d torn almost his entire bottom lip right the way around. Fish don’t have arms or legs to help them get by. All they have is their lips and mouths to gather food, build nests, and protect their young. Damaging these parts of their body can be fatal, even if they are swiftly released.

Play Video Hungry shark makes off with most of the prize catch for Adelaide fishermen. The West Australian Video Hungry shark makes off with most of the prize catch for Adelaide fishermen.

I had the sudden realisation that I had ruined this fish’s life. The one I’m holding in this photo is (and will always be) the last fish I ever caught. I was an arsehole. I’m sorry but, at the same time, forever grateful that he helped me flick the switch.

It should have been obvious to me from the struggle and panic I had witnessed time and time again that fish feel pain, just like all animals do. I’ve since learnt that they are actually quite intelligent. They can recognise each other, communicate, and grieve the loss of their companions. Some can even use objects as tools, and others make art in the sand to attract mates.

And we’ve all heard how the health of our reefs and oceans is hanging in the balance. I’ve seen it first-hand. Scientists say that if we keep killing sea animals at the rate we currently do, we will face a barren and desolate ocean by 2050, stripped of all traces of life. I am glad to have no further part in their destruction.

I’ve always loved the ocean and my fascination and love for its inhabitants has grown tenfold since I stopped treating them like disposable playthings. Replacing fishing with snorkelling has been a wonderful change in my life. To swim with and beside sea life is an experience many times better than fishing ever was.

I now find myself in the weird situation of having knowledge of fishing but not wanting to share it and having all this gear but not wishing to sell it. To me, it would be kind of like selling a young kid a knife.

So before you cast a line out this summer, cast a thought to those whose lives and homes you might be about to ruin.