Gulf of Mexico Fishery Management Council s6

Tab L, No. 2

1 GULF OF MEXICO FISHERY MANAGEMENT COUNCIL 2 3 RED DRUM MANAGEMENT COMMITTEE 4 5The Radisson Hotel St. Petersburg, Florida 6 7 January 29, 2008 8 9VOTING MEMBERS 10Karen Foote (designee for John Roussel)...... Louisiana 11Joe Hendrix...... Texas 12Tom McIlwain...... Mississippi 13Harlon Pearce...... Louisiana 14William Teehan (designee for Ken Haddad)...... Florida 15 16NON-VOTING MEMBERS 17Roy Crabtree...... NMFS, SERO, St. Petersburg, Florida 18Bill Daughdrill...... Florida 19Robert Gill...... Florida 20Vernon Minton...... Alabama 21Julie Morris...... Florida 22William Perret (designee for William Walker)...... Mississippi 23Michael Ray...... Texas 24Robin Riechers (designee for Larry McKinney)...... Texas 25Bob Shipp...... Alabama 26Larry Simpson...... GSMFC 27Susan Villere...... Louisiana 28Bobbi Walker...... Alabama 29Kay Williams...... Mississippi 30 31STAFF 32Steven Atran...... Fisheries Biologist 33Janet Bernard...... Secretary 34Assane Diagne...... Economist 35Shepherd Grimes...... NOAA General Counsel 36Trish Kennedy...... Administrative Assistant 37Stu Kennedy...... Fisheries Biologist 38Rick Leard...... Deputy Executive Director 39Michael McLemore...... NOAA General Counsel 40Charlene Ponce...... Public Information Officer 41Wayne Swingle...... Executive Director 42Amanda Thomas...... Court Reporter 43 44OTHER PARTICIPANTS 45Juan Agar...... NMFS 46Mike Bailey...... NMFS, St. Petersburg, FL 47Lt. Cliff Beard...... 8th Coast Guard District, New Orleans, LA 48Steve Branstetter...... NMFS

1 1 1Glen Brooks...... GFA, FL 2David Carter...... NMFS 3Anik Clemens...... NMFS 4John Cole...... LGL 5Marianne Cufone...... GRN, Tampa, FL 6Jerry Cummings...... Tampa, FL 7David Dale...... NOAA 8Dale Diaz...... Mississippi DNR 9Chris Dorsett...... Ocean Conservancy 10Libby Fetherston...... Ocean Conservancy, St. Petersburg, FL 11Martin Fisher...... FL 12Ted Forsgren...... CCA Florida, Tallahassee, FL 13George Geiger...... SAFMC 14Rick Hart...... NMFS, Galveston, TX 15Dennis Heinemann...... Ocean Conservancy 16Peter Hood...... NMFS, St. Petersburg, FL 17Kristina Jackson...... Sierra Club, Gainesville, FL 18Tom Jamir...... NOAA SEFSC 19Mike Jepson...... Gulf and South Atlantic Fishery Foundation 20Vishwanie Maharaj...... Environmental Defense, Austin, TX 21Jim Nance...... NMFS 22Julie Neer...... SAFMC 23Russell Nelson...... CCA, FL 24Bart Niquet...... Panama City, FL 25Brett Norton...... Tallahassee, FL 26Mike Nugent....Port Aransas Boatmen Association, Aransas Pass, TX 27Dennis O’Hern...... FRA, St. Petersburg, FL 28Clay Porch...... NMFS SEFSC 29Daryl Purchase...... St. Petersburg, FL 30Karen Raine...... NOAA 31Sam Rauch...... NOAA 32Darden Rice...... St. Petersburg, FL 33Scott Robson...... Destin, FL 34Bob Spaeth...... Southern Offshore Fishing Association, FL 35Lt. Brian Sullivan...... U.S. Coast Guard 36Phil Steele...... NOAA Fisheries 37Andy Strelcheck...... NMFS 38Richard Taylor...... St. Petersburg, FL 39Bill Tucker...... Dunedin, FL 40Sal Versaggi...... Tampa, FL 41Donald Waters...... Pensacola, FL 42Tom Wheatley...... Conserve Fish, Tampa, FL 43Bob Zales, II, .....Panama City Boatmen’s Assoc., Panama City, FL 44Scott Zimmerman...Florida Keys Commercial Fishermen’s Association 45 46 - - - 47 48The Red Drum Management Committee of the Gulf of Mexico Fishery

1 2 1Management Council convened in the Milan Ballroom of the 2Radisson Hotel, St. Petersburg, Florida, Tuesday afternoon, 3January 29, 2008, and was called to order at 4:00 o’clock p.m. 4by Chairman Karen Foote. 5 6 ADOPTION OF AGENDA AND APPROVAL OF MINUTES 7 8CHAIRMAN KAREN FOOTE: We’ll go ahead and convene the Red Drum 9Committee. All members are present. Adoption of the Agenda, 10Tab E, Number 1, any changes to the agenda? Seeing no changes, 11the agenda stands adopted. Approval of Minutes, Tab E, Number 122, are there any changes? Then the minutes will stand adopted. 13 14The Southeast Center’s Response to the Council Request and the 15council request was in Tab E, Number 3, and, Wayne, do you want 16to just remind us what the council requested, please? 17 18 SEFSC RESPONSE TO COUNCIL REQUEST 19 20EXECUTIVE DIRECTOR WAYNE SWINGLE: Under Tab E, Number 4 is the 21council’s request and you might recall that our Red Drum 22Committee was meeting with the panel that we established to look 23at doing another assessment and the issue came up of whether or 24not we would hurt the stock by going and collecting the animals 25we needed for that type of assessment. 26 27We decided to defer the whole issue to the Southeast Fisheries 28Science Center and Dr. Clay Porch is here today to respond to 29our request for that and we will use that as a starting point 30for additional action. 31 32CHAIRMAN FOOTE: Clay, if you could give us your PowerPoint, 33please, and thank you for coming. 34 35DR. CLAY PORCH: As some of you may remember, the last red drum 36assessment was done back in 1999, finishing up in 2000, and the 37next red drum assessment is scheduled almost ten years later on 38the SEDAR docket, in 2009. 39 40The recommendations from 1999 included some things that were 41very pertinent for this upcoming assessment and one of the 42recommendations was to collect age composition data for the 43offshore region by fishery independent surveys, preferably purse 44seines, because they’re non-selective, and then also to estimate 45the abundance via the mark-recapture experiments that were 46conducted during the mid-1980s and early 1990s, those two 47studies. 48

1 3 1Pursuant to that, the Gulf of Mexico Fishery Management Council 2asked us to answer three particular questions, one of how many 3fish would we need to collect in order to effectively 4characterize the age structure of this offshore Gulf of Mexico 5population and then second, how many fish must be tagged in 6order to achieve different levels of precision in the estimates 7of stock size, using the mark-recapture experiments. 8 9Finally, if we do these two things, what are the risks to the 10Gulf of Mexico red drum stock from carrying out those 11activities? In other words, you’re going to kill a certain 12number of animals when you’re taking samples to get age 13structure and some may die during the tagging process and is 14this really going to have much effect on the stock? 15 16When it comes down to the age composition, there’s a little 17nuance that we need to pay attention to and that is that red 18drum, like a lot of us, tend to associate with others of their 19same age. It’s not a matter of just going out and trying to 20randomly sample fish, but it’s also randomly sampling schools. 21 22Just to try and illustrate this point, suppose this is a picture 23of the schools of red drum that are in a particular area. You 24have some schools that are mostly larger, older fish and some 25schools that are mostly smaller fish and if you sort of naively 26just wanted to sample one school and you -- You sampled a lot of 27fish and so you had a big sample size, but you only sampled one 28school and you happened to get a school that was mostly smaller 29fish, like this, then when you incorporate that into the 30assessment, the assessment ultimately would have no choice in 31the end product but to conclude that the population offshore was 32mostly small fish and the mortality rate was really high, but 33it’s really an artifact of the fact that you didn’t sample 34properly and you didn’t adequately randomly sample among 35schools, to get a picture of what the overall average age 36structure is. 37 38What we did here is to try and figure out what’s the optimal 39sampling strategy, the number of schools you need to sample and 40the number of fish within a school that you should sample. 41 42We did this by looking at the surveys that have been done in the 43past, which basically sampled individual schools, and we applied 44what’s known as a bootstrapping approach, which basically 45assumes that that past data adequately represents the 46variability that exists now in the present stock. 47 48The idea is that you take all those samples that you did in the

1 4 1past and you randomly select one, and that would represent 2sampling a school, and then you would randomly draw individuals 3from that school and we repeat that process, drawing say, S, 4number of schools and then N, individuals, from each school. 5 6We do that for 500 replicates. In other words, we do this 7process 500 times and the idea is to find the number of 8replicates where each age class was adequately represented in 9the sample and we developed some criteria where we said what we 10wanted to achieve is that the sample proportion of age is equal 11to the true propionate age, plus or minus 0.5. 12 13In other words, you want to be close to the true age, and maybe 14a difference in the proportions of that 0.5, for all ages in 90 15percent of the bootstrapped samples. If you do that, then 16you’re likely to get a result that will be very useful in the 17stock assessment and help us to hone down what the true age 18structure is in the red drum offshore stock. 19 20We went through this exercise using all the surveys that have 21been done in the past in the northern Gulf. A number of them 22were collected by LSU and there were some by Auburn and some by 23the University of Alabama and some by the National Marine 24Fisheries Service. We ended up with I think it’s about 150 25total samples and we randomly drew from those. 26 27This is the sort of distribution we got. On the vertical axis, 28you’ll see the total number of fish sampled and not that you can 29read it, but that’s what this vertical axis is and the 30horizontal axis represents the actual schools that you would 31sample. 32 33The first thing you’ll notice is that if you sample less than 34thirty schools, even if you sample thousands of fish, you really 35aren’t going to have much chance of getting a good picture of 36what the true age structure is in the offshore population, but 37if you just increase that number of schools sampled to around 38forty, the number decreases very rapidly, the total number of 39fish that you need to sample, down to about a thousand. 40 41If you increase further, to around sixty, then the total number 42of fish you would need to sample is getting close to 700 or so 43and so probably the optimum sampling strategy is to sample 44between forty and sixty schools. 45 46You don’t get much increase on your investment when you get past 47forty to sixty schools. When you get past that, you don’t get 48much increase in your investment in terms of a decrease in the

1 5 1number of fish you need to sample. With that, you’re talking 2about sampling between probably around 800 total fish. 3 4In terms of the mark-recapture sample sizes, we didn’t actually 5have to do any work here, because this has already been done by 6Scott Nichols and Terry Henwood and that group, back in the 71980s and 1990s. 8 9What the found is if you wanted to get good estimates of the 10total offshore biomass, you needed to mark at least 20,000 fish 11and then about a year later, examine 50,000 more, to see what 12proportion of them are carrying tags. If you did that, you 13could expect a coefficient of variation on your estimates of 14biomass of about 10 percent, which is quite good. 15 16If you cut the number of fish marked in half, to 10,000, the CV 17would still be pretty good, at about 14 percent, and it 18deteriorates from there. If you marked 10,000 fish, but then 19instead of examining 50,000, you only examined 20,000, then your 20CV would be about 22 percent, which is starting to get a little 21marginal for stock assessment purposes, especially when you’re 22dealing with only one point. 23 24Another point to be made is that during the tagging process, it 25was found that about 3 percent of the tagged fish died and so if 26you tagged 20,000 fish, that means roughly about 600 fish would 27be expected to die. 28 29What we wanted to do is see if you included all these fish that 30might die, from both the age structure sampling and the mark- 31recapture experiment, would it likely have much impact on the 32stock? 33 34What we did is use the projection model from the 1999 assessment 35and we decided to be pessimistic and set the survey harvest to 36the maximum adequate sample size. That would be if you only 37sampled thirty-two schools, you would have to sample also a 38total of 5,000 fish. 39 40Then we use those projections and we subtracted the 5,000 fish 41and we did this under three survey scenarios: one, the baseline, 42where there’s no survey; one where we only had a one-time 43survey; and then another one if we did this every year. 44 45We applied that with three projected mortality rates: one which 46would be if you had stopped fishing; one if you fished at what 47is the fishing mortality rate at 30 percent SPR, the target; and 48the other if you fish at what were estimated then to be

1 6 1currently levels of fishing mortality rate. 2 3Though you can’t read the axis on this, the vertical axis 4represents the spawning biomass and the horizontal represents 5year, but the main point I want to make is that all these 6graphs, which represent, in this case, having no survey, a one- 7time survey, and an annual survey, they all look almost 8identical. 9 10In other words, if you fish -- This red line represents fishing 11at 30 percent SPR. If you do that with a one-time survey or 12with an annual survey, killing 5,000 fish each time, you see 13almost no difference. On this scale, it’s virtually 14imperceptible. The bottom there is you’re going to have very 15little impact on the stock from any of these types of studies. 16 17Bottom line recommendations, the age composition data should 18sample roughly forty to sixty schools, ten to twenty fish per 19school, ten if you’re sampling sixty schools. We recommend 20doing it about every three years, if we’re going to have 21something like a five-year SEDAR assessment cycle, and the mark- 22recapture abundance estimates, again, mark 20,000 fish and 23examine 50,000 about a year later. 24 25The bottom line is here that you may not actually be able to do 26that in time for the 2009 stock assessment, because the idea of 27the study is that you mark 20,000 fish during say a five-week 28period when they’re schooling up, but then you need to wait nine 29or ten months so that all the fish can mix properly and then you 30resample the following year, when they’re schooling up again. 31 32That’s how you get your estimate of total biomass. Right there, 33you’re talking about at least a year’s time. You would have to 34start today if you wanted to have information ready for the 2009 35stock assessment and that takes us to the end, if there are any 36questions. 37 38CHAIRMAN FOOTE: Thank you. 39 40DR. BOB SHIPP: I’m not on your committee, but, Clay, thanks for 41a presentation that’s got some specific numbers in it. It’s 42refreshing to hear that. My question though is would the 43Service do this, carry this out, or would it be subcontracted or 44have you got any idea of where you might go to get the work done? 45 46DR. PORCH: Either way could work, but the specifics haven’t 47been hammered out. I will say the last time we tried to do 48this, we tried to charter vessels, purse seine vessels, and we

1 7 1didn’t get many bites and so we ended up doing this by Fisheries 2Service personnel, hook and line. 3 4Ideally, what we would want to do is charter purse seine vessels 5and do the random sampling that way. Then you have the 6expertise to do it. 7 8MR. LARRY SIMPSON: Clay, can you remember offhand, in the 91986/1987 Nichols survey, how many schools were sampled and how 10many fish and as well, the 1999 fish and number of schools 11surveyed? 12 13DR. PORCH: I can’t remember the exact number. I think it was 14on the order of a couple dozen, but I can’t remember 15specifically. I would have to look it up. 16 17MR. SIMPSON: How about the fish? 18 19DR. PORCH: How many fish? The first survey was the one where 20they sampled a larger number and I believe the number tagged was 21approaching that 20,000. It wasn’t exactly that. The second 22survey, they had some logistical problems and it was much 23smaller. 24 25I’ll give credit where credit is due. My colleague Brian Linton 26did most of the calculations here and I have now given that 27document that gives the specific details to the staff and so it 28should be available, if it’s not already. 29 30EXECUTIVE DIRECTOR SWINGLE: Clay, assuming that we’re not going 31to be able to make the upcoming SEDAR thing, which SEDAR should 32we shoot for, the one three years later or -- How much time does 33it take to complete this cycle? You’ve got a one-year delay, 34almost, after tagging the fish before you sample and I don’t 35know about the rest of it. 36 37The age structure can be done all in the first year, I presume, 38but what sort of lead time do we need to have to get it into a 39SEDAR cycle? 40 41DR. PORCH: It would be possible to do the age structure work 42soon and it’s just a matter of allocating priorities, as far as 43which lab would do the aging work, whether we would end up 44subcontracting it out. I can’t speak to allocating priorities, 45although my boss is sitting here and so she might want to chip 46in on that. It is feasible to do, but it’s just a matter of 47where it fits into the scheme of the other species work we’re 48doing.

1 8 1 2MR. CORKY PERRET: Clay, I want to echo what Dr. Shipp said. 3That was an excellent presentation. You gave us something 4concrete, something to look at, something we can readily 5understand. 6 7Dr. Shipp’s question about who would do the research -- While 8your scientists at Pascagoula are great scientists and they 9tried to get purse seine guys to do the work, ten or twelve 10years ago when we tried to do it again and couldn’t and they 11decided to do it themselves and we had a total disaster off of 12Mississippi, with fish floating and so don’t try and do it 13yourselves. Hire somebody that knows what they’re doing. 14 15DR. PORCH: I think they learned their lesson from that one bad 16experience. 17 18MR. SIMPSON: If you do, go to the state and get the permits 19before working in their waters. 20 21CHAIRMAN FOOTE: I had to step out, but one thing that you 22mentioned was that part of the study way back when was with 23NOAA/NMFS people with a hook and line survey, which was not 24preferable to the purse seine study, but are there any other 25options for sampling that are out there? 26 27DR. PORCH: There’s two different things that we’re talking 28about. One was when we tried to do the mark-recapture 29experiment and that was I think 1989 or 1990. That was when 30there was some problems there. 31 32Later, we tried to contract with some purse seiners to just get 33samples of age composition and that didn’t work out and so what 34they did was just go with fish impasses and various places with 35hook and line, trying to get samples. The problem is that’s not 36directly comparable with the kind of sampling that was done in 37the past and that’s what we would ideally want. 38 39We want a picture of what the offshore stock composition looked 40like in the 1980s and 1990s and then a picture, using the same 41gear, same selectivity or non-selectivity characteristics, in 42the recent time period. That’s the beauty of purse seines. You 43essentially wrap whole schools and so it’s 100 percent 44selectivity on all age classes. Does that answer what you’re -- 45 46CHAIRMAN FOOTE: Yes. 47 48MR. PERRET: Clay, were you familiar in the early days that we

1 9 1had primary and secondary areas for red drum offshore? I think 2all of the samples came from the primary area. Wayne, does that 3sound right? 4 5EXECUTIVE DIRECTOR SWINGLE: Yes, we closed the areas off of 6Texas and Florida, because it appeared that we were having 7growth overfishing in those two states. The average size was 8down to two pounds. 9 10MR. PERRET: All of the purse seine work was done in the primary 11area off of Alabama, Mississippi, and Louisiana, if I remember 12correctly. To duplicate that study, I assume it would have to 13be done in the primary area, off those three states? 14 15DR. PORCH: You certainly would want to get a picture in the 16same areas, to compare like with like, but I would say that the 17upcoming assessment is intended to be a little more ambitious 18than past assessments and maybe have state-specific components. 19It would also be valuable to get pictures of age composition in 20the adjacent waters for every state, or at least regions, on 21something approximating a state level. 22 23MR. HARLON PEARCE: Dr. Porch, thank you for your presentation. 24It was a good one. It’s clear that we can’t get the tag and 25recapture done in time for the SEDAR we’ve got coming up. Is 26there anything else we can do with checking some of the schools, 27maybe before the next SEDAR, or is there also other information 28out there that we can pull upon right now to get some of that 29information for you that’s already done some of these schools? 30 31I believe in our meeting, there was some other groups that had 32done some studies and was taking samples already and how can we 33tie that into maybe doing something else to try and get some 34more information for this next SEDAR? 35 36DR. PORCH: This is the time to start tying it in, in 37preparation for the SEDAR data workshop, but preferably the 38better known those datasets become in the interim, it allows 39more people to start thinking about how we can incorporate them 40in the stock assessment. 41 42Some of them, I’m not familiar with. I’m sure the states have 43done some work that I personally am not yet familiar with, which 44I’ll need to become familiar with if I’m going to work with 45folks to do the stock assessment. Yes, we need to start talking 46now. 47 48CHAIRMAN FOOTE: Any further questions for Clay? Thank you very

1 10 1much and for Mr. Linton’s work on the paper, too. There’s an 2eighteen-page paper that Brian Linton did that is presented here 3in the PowerPoint that Clay worked on and so thank you all for 4paying attention to our questions. 5 6Next is Committee Recommendations. Does the committee have any 7recommendations to make at this point? Seeing none, any further 8business for the committee to discuss? Seeing none, we will 9adjourn. 10 11(Whereupon, the meeting adjourned at 4:20 o’clock p.m., January 1229, 2008.) 13 14 - - - 15