DNR Catfish Study

[Gordie]

I got this part covered.

MOOOOOOOOOOOOOOOOOOO..................

[bobbymalone]

however i totally understand all the work it is, particularly the catfish study

i put in about 20 seconds to send my self a text message with the length, species, time, and river mile for every cat caught, then troubled myself with 10 minutes of data entry once a week.

there is more science to be gleaned from the data than bag limit recommendation.

[Scott M]

One of the problems with the study is what do you actually do with the data? I would love to know how many flatheads over 40 pounds can be found per river mile on the Minnesota, or what the exploitation rate of channel catfish on the Mississippi river by angling is, if there are fewer big flats on the 'Croix than in years past, or any number of infinite questions. The river to me is one big question mark, a continuous unknown quality...that's the allure of fishing it.

However, that is the practical side to nearly all fish and wildlife research...you can spend a bunch of money and do your best to answer a question, and often you are left with more questions than answers and a data sat with biases (as in this case). I believe this catfish data could be a jumping off point to something bigger...a seat at the fishing roundtable for catfish anglers, increased participation and focus on trophy catfish angling in this state, a closer look at the regulations in question that so often are bickered about on these forums.

The DNR needs help on this just to get a notion of how many anglers really are out there. There have been creel surveys on the major river systems, but they all severely underestimate fishing effort and harvest because they were conducted during the daytime on random days. All of us on here know that the majority of big time cat fishing comes from sundown to sunup, and often its heavily saturated on weekends. There are also the limitations of sampling these fish. We all love to fish snags, rocks, deep holes...name one gear type that is good at sampling fish in those hard to reach locations? There is no perfect way to sample cats for abundance, either through angler diaries or electrofishing, as each have their biases, but at least you have something versus the incomplete data they have now. Lastly, I think its interesting to see how much these fish move. Do they have home ranges? Do they occupy certain waters at certain times? I'll be interested to see if this study keeps its momentum through 2010. I'm not sure if it was designed to be a post-spawn study, because as has been pointed out, the best time to get catch data is pre-spawn.

Give the study some time and while I and other cat guys resent resemble the "lazy" remark, please do your best to provide data in 2010.

[DTro]

Good thoughts Scott, thanks

[Scott K]

I think just the data that Dtro gathered during the KOTC would be very valuable to them. Darren should have dates, and measurements for a lot of fish. Would passing that info along to them be helpful in any way? I am sure if the DNR needed approximate locations of each catch, the fishermen that caught it, I am sure would be willing to give approximate locations.

I would think the BPCL data would be useful as well. Not that I am trying to make any extra work for anyone.

[DTro]

Yep, I bet I have non scientific data for over 500 fish in the past couple of years. See, I’m not that lazy

Approx Date

Length/Girth

I don’t see it helping much though because it is not a random sample, rather the bigger fish that people submitted. I would guess the size range would be biased.

[Scott K]

I would think any data that us catfishermen would be submitting would be biased on size. Since the majority of us target the larger fish, we use bait that the larger fish would eat, we fish in spots where the larger fish are. I know there are a ton of 12 inchers out there, but not to many of them are going to eat my bullhead, and by some chance I was just catching a bunch of them 12 inchers, I would move.

So I would think that any data I would be giving wouldnt reflect on the true sizes of the fish, but it would give an idea of the amount of larger fish.

[Gordie]

I knew you werent lazy Dtro

I my self am motivation challenged

[mplspug]

I think talking to Joel, he could tell you if the info would be worth while to send him. Of course, that would mean more work for you getting permission from anglers to send that info.

[rbs]

I was so lazy this year I didn't enter a fish in the KOTC.....I am going back to the couch!

[Scott M]

Saw this posted elsewhere, and given the importance to cat anglers, thought it was worth reposting here:

From Joel Stiras:

Only 147 catfish were tagged and released. 126 were channel cats, 21 flatheads. I recaptured one channel cat during sampling efforts two days later. Recaptured it less than 200 feet from where I released it after tagging. Had one angler report a tagged channel catfish caught and harvested, he was unaware of the catfish survey and tagging project. It was 19.1 inches long and was caught 15 days after I tagged it less than 200 feet from where it was released after tagging.

Channel catfish average length of tagged fish 20.4 inches. 12% were 24 inches or longer.

Flathead catfish average length of tagged fish 26.2 inches. 33% were 30 inches or longer, 14% (3) were 40+ inches.

97 pectoral spines were removed for aging. Not all spines have been processed yet and a few were broken/deformed and I was unable to assess an accurate age.

76 spines removed from channel catfish. Ages ranged from 3-22 years old, lengths ranged from 10.4-33.1 inches long. Eight year old channel cats ranged from 17.1-24 inches in length. One channel cat was 21.7 inches long and was aged as 16. The largest one sampled, 33.1 inches, was 18. The 22 year old was 26.8 inches and 7.2 pounds.

All 21 flathead catfish had a spine removed for aging. So far, ages range from 3-24 years old, lengths ranged from 11-44.5 inches. Two have been aged as 8 so far and they were 18 and 26.9 inches long.

Ten catfish caught in hoop nets were re-inserted back into the nets to observe tag loss, mortality from tagging, mortality from tagging and spine removal, and ability to escape the net. No tag loss or mortality occurred (6 of the 10 had a spine removed). Two out of the 10 put back in the nets escaped, one of which was too small to tag and was a miracle it was even captured the first time because it should have gotten through the mesh.

I’m still trying to plan a meeting to present some of our recent catfish work to catfish anglers and to discuss the ongoing tagging project and catfish angler diary program. Hopefully that will encourage participation in keeping the diaries as I would like that to be an ongoing project. I’m sure there are plenty of people that have reservations collecting the data I was asking for, and I would like to address those concerns in an open forum. The plan is to continue the tagging project for at least three more years, but these tags have the possibility of being retained for a long time and given the slow growth of these fish (and ages over 20), catfish anglers keeping diaries have the potential to be part of something really cool.

Note new e-mail address is in effect

Joel Stiras

Metro Catfish Project Lead

1200 Warner Road

St Paul, MN 55106

651-259-5806

[email protected]

[Scott K]

It would be cool if he became a member here and, spoke to us directly. I am sure he would get more results back then, that and if someone had a question on the process, he could easily answer it here, for all to see. I would love to attend any meeting he would set up regarding this.

Thanks for keeping us informed Scott!