I’ve written about BSB spawning & age at maturity several times of late. I truly believe Nature’s Plan for dealing with calamity can be utilized to great effect — offers the most simple restoration strategy; a strategy we employed until MRFSS mislead regulation into overly stringent regulation.. What I experienced owing our own pre-regulatory actions & bolstered strongly by early regulation was, primarily, a result of “all hands on deck” for spawning.
Well, I do hope you’ll read & consider these thoughts I have offered for so long.
From Fish Report 7/2/18..
On the East Coast we have a 10 fish limit on mahi. I'd be thrilled if we caught 10 for the boat while sea bassing..
Used to call them dolphin or dorado, but folks would get all wound up with "dolphin" on a menu. (Oh! We switched to dolphin free tuna and now they want to serve Flipper to us?!) Word usage transition must be very nearly complete if folks such as myself use "mahi" instead of dolphin.
In the Pacific, there are no limits. Even the staunchest conservation groups are A-OK with that because they grow so fast and begin spawning at 3 to 4 months of age.
Oceana is about as protectionist as they come in the marine world; this from Oceana's website:
"Though the common dolphinfish is heavily fished by recreational and commercial fishers, its high productivity and young age at maturity have so far protected it from overfishing. Populations are stable and are able to support the heavy fishing. Currently, scientists consider the common dolphinfish to be a species of least concern"
This is EXACTLY why I'm trying so hard to get management's attention on black sea bass's varying 'age at maturity.'
We can change it via size limit regulation as evidenced by the size of blue 'knothead' spawning males -- I witnessed when ALL sea bass in the ocean appeared to be in the spawning class. All scientific works prior to 2000 have sea bass spawning at age zero/age one. (After you correct for mis-aging. It was once thought that a 9 inch sea bass was 3, even 5, years old. We know today that's solidly age one.)
As management began sea bass still spawned in their first months of life or certainly by age one. But after the size limit hit 12 inches that youthful spawning, as evidenced by abundance/absence of less than 9 inch males, was replaced by populations where males matured at age 3 or better.
Instead of all our throwbacks being spawners, now it's just our keepers.. Spawning success from hot oil? Not so good.
Sea bass were far more prolific off DelMarVa when the entire marine population was in the spawning class.
Recent issues with survey equipment have created 'experiments' off Maryland's coast where large areas of habitat had virtually all sea bass driven out. As these areas recolonized, sea bass again reverted to age one spawning...
(I wrote about this at length in my 6/22/18 report if you'd care to dig deeper..)
There was a time when I fully believed our sea bass off DelMarVa were at "Habitat Capacity" - that we just couldn't hold many more UNLESS WE BUILT MORE HABITAT. That was in the early 2000s.
Every reef built in the 1990s & into the early 2000s was swiftly colonized by sea bass capable of spawning. We even had 1/2 day boats occasionally catching boat limits at 25 fish per-person when the 12 inch and 25 bag limit first started in 2002.
As soon as all reefs, even the hardest hit--pounded daily by 1/2 days boats; as soon as even those reefs were populated by 12 inch sea bass -- by 2003 the little guys ceased to be. They would not transition to male until 11.5 inches or better. Because they also grow fast, relative to their max size, these just-maturing fish become legal soon after.
Where once reefs/wrecks with amazingly heavy pressure STILL had a strong spawning contribution to make, suddenly the entire inshore spawning population (or dern near all of it) was being removed..
We're experiencing a spike in spawning production now; where it was All Hands On Deck for spawning as the MD Wind Energy Area recolonized. Hopefully the African Queen Reef will follow suite as it seems the Navy is not returning with the Sheila Bordelon this year.. (Knocking wood..)
But because to do so requires LOWERING our size limit to match the commercial limit of 11 inches, getting NOAA et al to even consider it has been impossible.
After all, they have to keep a sharp eye out for Overfishing. Maybe this year's catch estimates will show kayaks outfishing all commercial trawl.
In an estimate system where shore fishers commonly have the largest average sized sea bass catches, any illusion of catch is quickly assigned the title, "Science." Would that population biology & ecology might take catch estimate's place....
So my theory on "size limit's influence on age at maturity in sea bass" will be nigh impossible. Where my other assertions are well supported in science except my beef with catch estimates..
My argument to compare Private Boat against the more well-known & measured Party/Charter landings hasn't gained an inch. I can get 100 regulators laughing out load by comparing Private Boat's insane estimates against Party/Charter, but they'll take not not one step toward using such comparison to truth the data.
MRIP estimates are, after all, supported by brilliant statisticians who do not fish, yet the numbers are implausible beyond belief----and about to become many times worse under NOAA's impending "Recalibration."
Currently an estimate stating Shore Fishers from one state, in one two month period, catching more fish than ALL COMMERCIAL EFFORT causes no discomfort to regulators.
I've detailed many such exaggerated claims over the years.. So far as NOAA's concerned, there is no height recreational fishers cannot achieve where over-harvest of quota is concerned.
My thoughts on sea bass spawning production, however, cut against all teachings in fisheries science. Where today science holds "big old fecund females," or "BOFF" as the best way to bolster egg production and therefore a population's spawning production is increased, my experience with sea bass populations shows BOFF to be wholly ineffective.
In fact, I believe BOFF-type thinking has curtailed production so badly that DelMarVa's nearshore reef spawning production has been nearly lost.
Indeed, today's sea bass population is mostly comprised of large females--larger than scientists once believed even existed prior to 2000--yet spawning production is minimized despite the greatest female population of sea bass since fishing began.
For years & years I’ve been trying to convince management of size limit’s affect on black sea bass production: how ALL sea bass found at sea prior to 2002 were once spawners, but when the size limit increased to 12 inches their age at maturity—(or ability to participate)—shifted from age zero/age one to age three or better.
This spawning participation is, I believe, evidenced by the blue hump on a male sea bass; the nuchal hump. We call them knotheads..
When I was told in 1992 that:
"All sea bass have spawned by 9 inches (age 1) and some twice," it was a true statement. Since 2002 it has been false. Except in one instance..
It's not crowding. Sea bass were astoundingly crowded in the late 1990s/early 2000s, but they still matured young as, so far as we knew then, they always had.
When a lot of age 3 fish started populating reefs however, younger fish ceased showing the nuchal hump -- almost completely. When the size limit was 11 inches and smaller, all the sea bass we threw back were spawners. Some for another year too.
When the size limit went to 12 inches (and then 12.5) almost none of our throwbacks were spawners. They grow 3 inches that 3rd summer.
A 12 inch male thrown back in May will be legal come mid-June.
Inshore grounds where fishing pressure is heaviest continue their downward sea bass population spiral, except on new reef.
The greater fishing pressure is, the greater size limit impacts production.
Used to be our heavily pressured inshore reefs contributed importantly to spawning production -- more so, I believe, than even distant & lightly fished reefs populated by jumbos. Pre-2002 size limits 11 inches & below forced ALL sea bass into the spawning population.
Timing is everything.. Just as cbass are joining the spawning stock today--just as they are about to have their first spawn -- they also become legal. Spawning population ain’t much good in a fry pan.
Experiments with sea bass aquaculture from:
http://www.unh.edu/news/news_releases/2 ... 1bass.html
Berlinsky’s team found that females were more likely to change sex when no males were present in the tank. Additionally, the fish were more likely to turn into males when kept in crowded tanks.
This a development that assures reproductive success on even far-flung isolated reef communities. It's at the core of my argument.
I believe we can purposely trigger age one fish to become males and start spawning simply by lowering the size limit a bit.
Well, we've recently completed an (unplanned!) experiment on this idea of shifting age at maturity. In the spring of 2016 we had our worst 'spring run' of sea bass ever. Ever.
We also had the utter evacuation of at least 500 square miles of seabed -- sea bass & flounder had completely left the area affected by sub-bottom profiler surveys in the MD Wind Energy Area by the summer of 2015. (see a video I had made in Jan 2016 with video from 2004 & the last day of August, 2015 - https://www.youtube.com/watch?v=46ahNqo8geE )
After the surveys ceased in late summer 2015, recolonization for spawning's purpose began in 2016. I predicted a return to sub-9 inch male spawning colors owing there were no males staking their claim to prime habitats.
It wasn't just the wind area. Though especially there, we also saw small males on many reefs/wrecks outside 15 fathoms owing, I believe, to suitable habitat unoccupied by age 3 or better males.
This recent spawning population of age 1 & age 2 sea bass propelled us to today's better fishing.
2016's enlivened spawning production became 'age one' on January 1st, 2017. They were fully in the spawning class that summer. We had the most 'knothead' sea bass off here in a very long time. In 2015 I was still writing how we'd only see less than a dozen under-9 inch male sea bass a year - hadn't since 2002.
In 2016 it was fairly commonplace to see small males again offshore a bit in some areas. Small, age one males were a frequent occurrence in 20 fathoms, some places 15 fathoms too.
Perhaps the greatest reason this is so important is because every teeny, tiny bit of anything sticking above the seabed is colonized by some little guy and his girls. Increasing the percentage of the population in the spawning class makes for great reproduction.
Now age 2, they're making for a lot of throwback action. Soon the fastest growers will be legal.
Age 1 - 112.92g - 0.25 lbs - 5.5 to 9.1 inches.
Age 2 - 243.19g - 0.54 lbs - 8.7 to 12.2 inches. (our size limit 12.5 inches)
Age 3 - 395.48g - 0.871 lbs - 10.6 to 16.1 inches.
Age 4 - 604.69g - 1.33 lbs - 13.4 to 20.5 inches.
Age 5 - 861.95g - 1.90 lbs - 16.5 to 22.0 inches.
They can live to 12, perhaps older, but growth slows as it must..
Those surveys about drove me mad. Guvmint said of survey noise: "They're as quiet as a ships propeller" ..couldn't do a thing to reef fish.
But fish fled the noise - left entirely after a couple years. As in so many things in nature: From Catastrophe, Abundance. If I cannot get science to pay attention this time, there may never be another.
Always able to find "overfishing" - MRIP even has 2016's MD Shore anglers loading up on 1.3 pound AVERAGE SIZED sea bass, and far more than Party/Charter caught that same year. We'll have a 15 inch size limit and some short season like up north -- all to "Prevent Overfishing."
A fishery that survived true overfishing's darkest days of even distant water fleets of factory trawl pummeling US fish populations; our recreational sea bass fishery may not survive management's ignorance.
I absolutely believe a full suite of management options, including Ecology & Population Biology, can send sea bass populations above even those that must have existed during industrial fishing's earliest days.
It'll never happen so long as managers find regulatory comfort in recreational catch data that couldn't possibly be true.
Capt. Monty Hawkins
Partyboat Morning Star
Ocean City, MD