Venting Deep water bass?

[Big B]

I was curious if the DFG has done any studies on catching deep water largemouth? I know studies have been done by other agencies on Ocean Rockfish showing high rates of mortality due to needling or improper needling of these fish. I found this when doing some research on the subject.

"Alaska DFG seminar on deepwater release of rockfish, using the leadhead jig. The comments made by the ADFG biologists involved indicated a relatively poor survival rate among vented rockfish, based on tagging results. Essentially they would tag the fish and release it. The number of fish caught again was much higher with the fish released by the leadhead jig than those that were vented. From that data they concluded that vented fish had a much higher mortality rate. Clearly some vented fish survive, however if there is a better way that is less traumatic to the fish, we should do it!
I agree that another problem with venting is the inaccuracy of fishermen to vent the gases out of the fish's abdominal cavity without harming other internal organs. And it is my understanding that we are not venting the swim bladder itself; the bladder has already ruptured. We are venting the gases that escaped from the ruptured swim bladder. The Florida information suggests that the ruptured swim bladder heals itself in a few days. A case could be made that a ruptured swim bladder could develop an infection, however venting opens the body cavity to the ambient environment. Seawater can enter through the wound, and this is where the infection comes from in vented fish.
The data from last year's study of the new deepwater release method was incomplete at the time of the seminar, therefore ADFG was reluctant to promote the method just yet. But I would expect to see something official on this pretty soon. I believe the study was scheduled to continue this summer."

So far what they have found that has a far less mortality rate than needling are the jighead method or a weighted basket.

"Take a lead head jig (I use a 20-24oz) and crimp the barb. Now, tie your main line to the bend of the jig so the lead head is hanging down. Place the hook in the fish's mouth and drop them down to the bottom or the known depth at which the fish was caught. Next, set the hook. You may have to set the hook more than once to get the fish off. Wait a minute to make sure the fish does not come back up. This happens one out of ten times."

"I use the weighted crate method. A large "milk crate" type crate, with a smooth interior, weighted such that it hangs inverted. It's attached to a 75'+ poly line attached to a spare cleat. (The line has a small bouy ball on the end just in case). Crate is rigged and ready when fishing so that if I inadvertently catch an unwanted rockfish, I simply unhook the fish next to the boat; with the fish floating on the surface next to the boat I immediately cover the fish with the waiting crate and release it. The crate takes the fish straight down. You only need to get them back down below 60 feet. Once below 60' the fish quickly recovers and swims out of the crate. This method results in absolute minimal handeling of and damage to the fish and gets it back down as quickly as possible, which is important. This method also eliminates the need to re-rig a rod, or have a second rod standing by rigged for releases, and as soon as you let go of the crate you can continue fishing for your targeted species."

I know this info is about saltwater fishing but I do believe the pressure at depth is the same and would have the same effect on the Bass at DVL. Just some info I wanted to share.

Tight LInes
B

[pigdestroyer]

There have been a few discussions about this.
http://fishingnetwork.net/forum4/sho...ling-a-Bass%29
http://fishingnetwork.net/forum4/sho...7-fizzing-bass

There was even a video made for the basket technique.
http://www.youtube.com/watch?v=L3Vwd-ccu6w

[Big B]

Thank you very much for the response pigdestroyer.

[kwin]

Google (scholar):

Feathers & Knable 1983, Lee 1992, Morrissey et al. 2005, Kerr 2001, Shasteen & Sheehan 1997

[Matt_Magnone]

this is good stuff.

At a competitive smallmouth bass (Micropterus dolomieu) angling event on Rainy Lake in northwestern Ontario, we evaluated the effects of post-weigh in fizzing on the behaviour and short-term survival of three treatment groups after release: (i) barotrauma fish without fizzing (N = 8); (ii) barotrauma fish that were fizzed (N = 9); (iii) fish without signs of barotrauma that were fizzed (N = 10) (sham control). Small external radio transmitters were affixed to the fish and tracked for 4 days. Fish were released at a common site and we assessed their dispersion at specific distances from the release site (50, 250, and 2000 m). All fish survived the 4-day monitoring period. No differences were observed in the time it took each group to disperse from the release site. Furthermore, there was no statistical evidence that fizzing influenced mean daily movements relative to controls, though a consistent trend was noted where fish that were fizzed displayed greater movement than non-fizzed fish with distended swim bladders. This study revealed that fizzing by trained experts is not detrimental to barotrauma fish. However, if done improperly there is risk to vital organs suggesting that there is merit in exploring other less invasive approaches to recompressing fish. Because our statistical power was generally low, further research is needed to determine whether fizzing should be encouraged or dissuaded to maintain the welfare status of the fish, decrease sublethal impairments, and reduce mortality.