Toona Research

[fisher]

I'd have to agree with Scotty about killing longies they are a fish thats to special to only be caught once.Like most fish if there handled right they usually swim away ok and if more people got into tagging alot more information could be obtained without killing them.I had a recapture of a longie last year the fish was first captured by a guy from Bribie Island GFC then recaptured and retagged be me of Bribie the fish had traveled 12 Nm and was out for 44 days.It swam away just fine after the second capture and hopefully will be caught again someday and hopefully released again to give another angler the same enjoyment that we had,how much is that fish worth?If everybody that targets longies or any tuna for that matter tagged them there would be a lot of tuna swimming around with tags in them giving us lotsa imformation on the species such as groth rates and movement up and down the coast.I'am a strong believer in reserch but yet to be convinced that killing them is they way to go,with three tuna fly comps per year there could be a lot of tuna taged each year by fly fisho's alone. All the best to all the guys fishing the tourney this weekend it's the first time I've missed it since it started but don't fancy towing the new boat all the way down to Bribie when there's tuna up here in H/Bay.Go hard Scotty Shawn and Jason three from three hopefully!!! All the best boys.Paul

[pkcchong]

I'd have to agree with George on this. A lot of fisherman have a belief that the fish they release will, in the majority, survive. I think the survival rate depends a lot on the fish, length of fight and time out of the water. Flyfishing is probably the fishing technique of worst choice for tuna survival. Tuna a fast fish and need a continuous supply of oxygen, more so than any other type of fish. This need is going to be greatest at the end of a long protracted fight where they will have a huge oxygen deficit (hence they are tired).

The human analogy is to tie a springy rope to someone and chuck them into a paddock full of bears and let them run around for 20 minutes. Then pull them in when their really huffing and puffing and shove their head underwater in a bucket for a good 2 - 4 minutes and take a nice picture with an underwater camera. At the end, kick them out. They'll crawl away to die. You can't live without oxygen for 3 minutes and that is without the stress of running a marathon!

Flyfishing is an inefficient fish winching technique compared to 60 lb braid and dragging them in, and the tuna are going to be more tired at the end of a fly fight (even more so for a big tuna). Hence probably the minority of these fish will survive. Sure they may swim off but I'm sure a lot become crab & shark bait. I'd rather eat them. So if I were going to release BIG tuna, I'd expect to bring them to the boat very green and full of energy and that usually precludes flyfishing. Note the japanese use 80 lb braid for big GT to bring them to the boat within 10 minutes. Any longer and they realise the fish dies release or no release.

[Maxg]

Interesting but a Guy Brad Chase did some blood sampling on Bluefin tuna in the atlantis a few years ago, and came up with Lactate and blood pH against time on line. Interesting to look at considering that the blood Lactate and pH both bounce around in sync with the fish running around, and then after about 30 minutes it start to getr very high, and its white muscle lactate resulting from energy depletion.

[Maxg]

Next one Max

[team_mongo]

Good stuff max!

Where did you get the info? I'd be interested in reading it. Wow a lactate of 200mg/dl (about 20mmol/L) is uniformly fatal in humans! I note the graphs don't have PO2 on it though, which is probably more important.
Is there any references?

George