I am often asked by many of my charter clients and friends, “What is the biggest fish you have ever caught?” My answer is always the same: The biggest ones got away!

Capt. Bart Miller caught a 1,656-pound blue marlin in Hawaii, and wrote a great story about an even bigger one that escaped capture. I am sure many of the Australian captains that have caught black marlin of more than 1,000 pounds have a story about "Old Julie" that they saw or lost that was bigger than the ones they have weighed. Then there are fish like in Hemingway's Old Man and the Sea, where the sharks win instead of the angler.

Nowadays, it is great to hear of so many people releasing their big fish. And at the same time, I hear quite a few old-time captains saying that many of these young guns have never killed a huge marlin, so how would they know what one would look like? Photos rarely show how big they are (or aren’t).

How do we judge any fish’s weight? We weigh a few big fun fish—mahi, tuna, wahoo—and once in a while we see a big marlin or tuna being weighed in a tournament. We also can take measurements and run a mathematical formula after the release to get a fairly close guess of the weight, but it’s just that: a guess.

The really good news is that because everyone has cameras in their phones, we can get some great memories and have everyone else see that big fish you just released. Also, with the GoPro cameras mounted all over the boats these days, you can get a better idea of how big the fish is (or isn’t). Is it the wide-angle lens that makes these marlin look smaller than we think they are?

I am fortunate to have harvested quite a few fish for world records, including black and blue marlin, swordfish and other billfish. Along the way, I got to be pretty good at guessing the weights of these species. The one thing I always did was to guess under what I thought the marlin really weighed. That way, everyone was happy about the catch. If we guess over the actual weight, people tend to be disappointed with what is still a great accomplishment.

We caught a nice marlin in transit from The Madam on the way to Africa in 1988, but had no choice but to let it go. And I already mentioned in a prior column about the really big blue marlin that I was the angler on, fishing out of Tropic Star Lodge in Panama a few years ago.

When we got the leader for the third time, my wife Debra Todd jumped in with her underwater camera to try to get a few pictures. The marlin was behaving nicely until we tried to head back to where Debra was. Halfway back, the marlin decided enough was enough, shook her head and the hook pulled out. No photos—except for the one that Debra took when the marlin was jumping behind the boat. I do know that if that particular marlin was really tired, I would have considered putting her on the scales.

I was glad she swam off healthy, but still. When I show the photos to a few friends that have caught thousand-pound marlin, they all say she was a really nice one and I should have weighed her. But to me, a marlin that frisky and not in a tournament or in contention for a world record deserved to live.

Capt. Skip Smith chimes in on tournament fishing.

When someone decides they want to harvest large marlin, whether in a tournament or just hunting a really big one, it excites the crew; most all of the crews I know love the opportunity. Personally, I do not understand the response from the gallery. These same people will kill the largest of every other species without hesitation, as they post photos of big dead swordfish, groupers, mahi, tuna and even snapper. No matter what species you are after, killing the largest is still the same as someone who harvests a large marlin.

Then there are the stories of the big ones we release during the day. Back at the bar later that night after a few cocktails, they somehow gain another 500 pounds. Now that’s a good fish story!