FEB 27, 2013 - CAPTAIN MONTY HAWKINS - ON SEA BASS - Science & Observation Are Met - SIZE TO WEIGHT TO AGE TABLE HERE

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FEB 27, 2013 - CAPTAIN MONTY HAWKINS - ON SEA BASS - Science & Observation Are Met - SIZE TO WEIGHT TO AGE TABLE HERE

Postby EC NEWELLMAN » Wed Feb 27, 2013 1:12 pm

The latest from Captain Monty Hawkins, owner and operator of the fv MORNING STAR out of OCEAN CITY MD>

NOTE: A big thanks to Captain Monty, who spent a good deal of time putting this table together. Fishermen, you should get a good idea on approximately how old the sea bass you catch is. This thread will have a STICKY due to its importance.
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"Science & Observation Are Met"


Today we have just 15 or 20% of our sea bass in the spawning stock. These same fish are also just-recruited to the fishery. I think in 2000 it was closer to, or above, 95% in the SSB... All age-at-weight & length-at-age assertions are from modern works included below or attached.

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Science & Observation are met, Ya'll just don't know it yet..
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Greetings All,

I doubt I'm getting any traction with my Age @ Maturity thesis, with my idea we've diminished the sea bass spawning stock because of recreational size limit increases.
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If we are to create real & lasting abundance, if we are ever to create a sea bass fishery better than any now imagine, then we must understand how to force spawning as a tool for management and combine it with the power of habitat expansion.
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Many years before fed/state regulation; In the spring of 1992 I began strictly enforcing a 9 inch size limit. I chose 9 inches because a MD biologist, Nancy Butowski, told me every 9 inch sea bass had spawned, some twice.

When lit-up in spawning color, male sea bass --blue heads or knot heads-- are very simple to spot.


It follows that where small 7/8/9 inch sea bass are observed to have transitioned from female to male there ought to be active females of similar or same size. What science claimed then was true then: Yes, by 9 inches every sea bass has spawned.

That some sea bass had even spawned twice made perfect sense to me..
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I wrote the short report below on 6/4/03. That summer; just five years into regulation, the second year of a recreational bag limit and twelve years after we'd begun 9 inch self-regulation, my clients limited-out most of the time.

We routinely caught fish, on purpose, with bare hooks.


Occasionally entire days would pass when we didn't use bait, just unscented soft-plastics. Only on reefs with the highest pressure would I see small male sea bass. I could tell how much pressure a reef had by the size of its males.. That fall, however, I noticed something was missing -- the little guys..
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6/4/03


For about 2 weeks now we've been encouraging customers to fish a 13 - 13 1/2 inch size limit.

Some are fishing a 14 inch limit.

The state/fed size is 12 inches this year.

I don't know how long we'll be able to do that. And, truthfully, not everyone is limiting at these larger, self imposed, sizes. A customer told me he was done yesterday. I asked if he had a limit, "No, only 21, but I can't close my cooler!"

Sure beats a bunch of guys "high grading". That's when folks sneak smaller dead ones by the rail and re-fill their limit with larger fish.

I still hold that sea bass fishing is the best I've seen in my 24 years. Pool winners are averaging 5 1/2 pounds, 22+ inches. I've got LOTS of spots that I've not hit yet. There are some really awesome days coming up.

And from 7/9/03

Hi All,

Used to be that betting on a good day of sea bass in July was a long shot. Wow, how that has changed... I've had many customers this week tell me they have never seen bass fishing this good. (that's because they were not out this spring!) I took some scientists offshore today hoping to find at least a handful of ling (red hake). No Joy. Maybe a wake up call there in research circles. *

Red hake remain absent & sea bass fishing is nothing at all like that now. Oh, it's plenty good because its choked-off with shorter seasons and we have an amazing summer flounder fishery; but along DelMarVa the BSB population is perhaps only at a third of its peak.

I'd also like to point out fishing pressure on tautog was much lower with sea bass in abundance.

We fished cbass virtually unhindered by season during early management and the stock grew amazingly. Now, even though we've added an enormous piece of rocky New England coast to their spawning habitat, quota & season are diminished..It remains that I once would catch & keep in a couple days the sea bass I now catch all summer.

See anything amiss with that? I surely do.

Something has completely removed young sea bass from the spawning population along DelMarVa.

I believe its the size limit.
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Its also very much true that those in management & fisheries science believe K (as in habitat carrying capacity) is a constant, a theoretical; that it can not be changed.

Yet when I wrote those 2003 reports I honestly thought we were at holding capacity - And, very importantly, I was writing & writing & writing to management about our expanding natural hard-bottom reefs..Almost entirely contracted again in gear-impact, that habitat expansion is now lost and the habitat type remains absent from the literature.

Habitat loss a bitter-pill; I believe the primary reason for DelMarVa's diminished cbass production, however, is because only a small fraction of today's sea bass population is in the spawning stock biomass, SSB, whereas in 2000 virtually every sea bass found in the ocean during summer was active in spawning.

While some doubt this shift has occurred and see no cause for managerial concern; back-then I often held more age-one male sea bass in an hour than I now see in a year.
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My assertion that a female sea bass can switch sex in as little as a few weeks may seem outlandish. Indeed, it may be that such a swift transition does not immediately result in a fully-capable spawning male. However, I was able to find the citation I'd based my premise from: David Berlinsky, assistant professor of zoology writing on on sea bass aquaculture, University of New Hampshire:

"By turning off estrogen production, Berlinsky says, he can turn a female fish into a male within a week."

http://www.unh.edu/news/news_releases/2 ... 1bass.html

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I have sourced all my age-at-weight & length-at-age assertions from modern works and have them below or attached.
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Today we have just 15 or 20% of our sea bass in the spawning stock. These same fish are also just-recruited to the fishery. I think in 2000 it was closer to, or above, 95% in the SSB. Increased production then allowed many to escape harvest resulting in more large fish available to anglers. Production is especially diminished inshore where the heaviest fishing pressure is..

The population spike in the early 2000s was no accident, No happy coincidence of skyfall; No, "Gee, weren't we lucky to have good recruitment."

It was fishery management working.

With MRFSS calling the shots recreationally, management failed to see it. We need to experiment with a reef or reef-group to see if what I claim is true, to see if age at maturity can indeed be manipulated for greater production.

We need to know.

If I am correct, any large area or small isolated individual piece of reef can be set aside as an 11 inch recreational limit area and we would swiftly see -- perhaps in just a few weeks -- younger female sea bass switching to male.

It could be done by moving them or by allowing retention at that spot--on that reef..

An inshore reef with a lot of half-day party boat pressure will scarcely have many fish to begin with. This experiment needn't unleash overfishing's demons.

We would have to assess a reef's population at about the middle of the second week of May, then fish them down to size limit on that spot by the last week of May (easily done with inshore fishing pressure) & keep them fished down.

Stage set: compare age at maturity in June, July & early August not only to the same reef in May, but also nearby reefs..

What a wonderful management tool expanding an SSB with already-available fish would be.

Its preposterous to allow MRFSS-based plug & play regulation to completely sideline real fishery management.
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I believe we can raise K by habitat protection/enhancement/restoration. I believe giant leaps in fishery restoration await finding and manipulating K; that we can and do create population growth by expanding habitat, that we can and do diminish populations in habitat loss; I think too we can increase spawning production by simply lowering the size limit: I believe management of habitat increase & manipulated SSB is where explosive exponential population growth becomes possible.
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We Must Address The Science Gap..

Science from pre-management is in wide use for forming sea bass regulations. Aging, length-at-age, & weight-at-age have all been dramatically improved, but these improvements have not been corrected for in the literature.

Similarly, the paucity of habitat information is so great that this species is thought to live on soft-sand in winter in the Mid-Atlantic. (see EFH doc) Clients were catching sea bass on a recent winter tautog trip. (2/22/13) We were not on soft sand nor has any recreational cbass fishing trip I've ever heard of occurred on sand.

I did observe sea pens with Capt. Rick Younger's deep-drop video gear in what appeared to be soft sediment while catching blueline/gray tilefish. It is possible that sea bass are there, amidst those sea pens, at this very moment.

To date, Wigley & Theroux's 1981 work remains commonly cited in sea bass management. Although Those Geologists Found No Hard Bottom Reef In The Mid- Atlantic Bight ..fishers do everyday.

How sea bass use these undiscovered habitats, specifically in spawning site habitat fidelity, remains management's greatest unused tool in quota management. No melding of science can firm management's foundation when the science is unavailable, No 'best course' can be charted when new science remains outside the literature.
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From the "1995 Review of the Development of A Joint ASMFC/MAFMC Plan For Black Sea Bass" page 55: "In spite of a potential maximum age of 15 years, the age structure is highly truncated with only 4.5% of the stock in 1993 greater than age 3. Since most black sea bass begin life as females and change to males between ages 2 and 5, the truncated age structure may result in a shortage of males and ultimately disrupt production."

Here from the 1993 NOAA Technical Memorandum NMFS-NE-143, BSB EFH Source Document: 50% are mature at about 19 cm SL (7.5 inches) and 2-3 years of age (O’Brien et al. 1993).

And from the EFH Source Document 1999: "Wenner et al (1986) & Alexander (1981) found mature fish at 10-11 cm (age 1+) off South Carolina & New York; a majority of fish were mature at about 19 cm TL (7.5 inches)and at an age of about 2 to 3 years."

Also from the EFH Source Document: In the South Atlantic Bight, Cupka et al. (1973) reported that both sexes mature at smaller sizes (14-18 cm SL) (5.5 to 7.1 inches).

According to the 1996 Chesapeake Bay & Atlantic Coast Black Sea Bass Fishery Management Plan: Fifty percent of black sea bass are sexually mature at 7.7 Inches (Available at NSCEP by searching title.)

(P. 13, Kendall 1977, "Males first appear as 3 year olds.." versus P. 15 of the same document, "Larger fish are all males. Nearly all fish >25 cm (9.8 inches) are males. Thus catches of large fish will consist of males." )
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Assuming all these scientists could measure, they must simply have had bad aging data.

We know today that these "mature 2 to 3 year olds" were really age 1.

We know 10 to 11 cm "age 1" mature fish were really age zero.

We know the early management claim of a Mid-Atlantic sea bass population 4.5% above age three is extremely unlikely: Its far more likely those researchers actually found 4.5% of the population was age-one.

We know, or at least I know, there are no more "7.7 inch" sexually mature males.

We can expect Kendall would be positively shocked to find almost no 10 inch male sea bass in the entire population, that everyone would laugh at him for calling 10 inch sea bass large: they're tiny throwbacks today..
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Because sea bass presently have a 12 1/2 inch size limit, a large percentage of the population really is age 3.

Unfortunately, its also true that today's sea bass are just maturing at this size. You could accurately quote AGE from early works for today's maturity -- and we do.

But at the time of those early works their measurement of LENGTH at maturity was accurate.

Age was wrong, length was right.

Now age is right & length is wrong.

Below I have tables & charts from recent research fully supporting my assertions.

Today's BOFFF Hypothesis (big old fat fecund female) management style fails given the incredible success we've already seen a decade ago with sea bass management. The population spike of the early 2000s was due to young fish creating abundance.
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Please see attached Length at Age chart, G. Shepherd, to compare age at length as understood now vs then.
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Here I've assembled these various charts for comparison with older works.
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Age WAA (g)

Age/weight from: Estimating Black Sea Bass Natural Mortality Using Several Methods - Julie L. Nieland and Gary R. Shepherd - October 2011 Original Graph in BOLD {page 28 - Table 1.

Black sea bass mean weight at age (in grams)..} Conversion to pounds and brackets ( ) here from M. Hawkins and of no association to the authors.

Length Conversions Computed From "BSB Probability of Age at Length Key - G. Shepherd" by M. Hawkins. (attached) No one has reviewed these simple computations by M. Hawkins..


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From tag returns we see a faster growth rate in southern Mid-Atlantic tautog than in their northern range. Presumably such a growth variance could also be found in sea bass.

As all living things, some individual fish grow faster - we know a 4 year old sea bass @ 20.5 inches will weigh more than 1.9 pounds..

Management should also look for false foundations of modern regulation in early MRFSS weights. From 1981 to 2000 the MRFSS has the average MAB sea bass at about .4 K or .88 pounds. That wouldn't have occurred until 2002 or so. The real average weight before and especially during early management would have been 0.125 K or .25 pounds....
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I believe Surplus Production, a basic tenant of fishery management, sources from the biological instinct of fish to spawn younger when under pressure.

I believe Black Sea Bass are now behaving as though their reef populations are at peak even though we clearly understand they are not.

I believe sea bass are naturally slowing down spawning activity as every animal in the world does in an overcrowded situation. But their cue is not in "crowding" or reef population density as I once thought it must be. No, instead it is the size of other fish around them that trigger or delay spawning..

I believe management can 'trick' sea bass into thinking their habitat is unlimited by lowering the size limit and forcing them to spawn.
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I'm unsure of actual spawning behaviors; Have yet to see bowls/tail-swept depressions/nests in the literature as I see when I video reef habitat. I certainly don't know about sea bass leks or harems.

I do know I used to see more small mature males in an hour than I do all year. That's not an exaggeration. Whether accelerated spawning experienced for decades was a result of more young fish spawning or young fish learning to spawn earlier makes no difference: Spawning Was Accelerated, Fish & Fisher Benefited.

Now we don't. Do not brush this aside.

If we are to create real & lasting abundance, if we are ever to create a sea bass fishery better than any now imagine, then we must understand how to force spawning as a tool for management and combine it with the power of habitat expansion.

My Regards,
Monty
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Capt. Monty Hawkins
mhawkins@siteone.net
Party Boat "Morning Star"
Reservation Line 410 520 2076
http://www.morningstarfishing.com/

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EC NEWELLMAN
 
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