View Full Version : striped bass age versus egg viability


Pete_G
04-05-2006, 07:38 PM
This was discussed briefly on another board (nothing really came of it) and some of the ideas were popping up in the OTW Striper Cup thread as well. Didn't want to hijack that, so I started this.

When do a striper's eggs actually become less viable? I googled the Internet literally for hours to try and find some answers to this and I found nothing useful.

Are a 40 pounder's eggs less viable? And who's to say this is an old fish? At 40 pounds, that fish may have conservatively another 20 pounds of growth in it's life. My only hang up with the old eggs theory is I often see it mentioned by commercials and charter captains, so immediately I get suspicious and would love to have some real data on the matter. That and I'm just not convinced a striper is "old" if at 40 it is only at 2/3 of it's potential body weight.

Show me some data! Prove to me that the idea that a 40 pound striper is "old" and past it's prime breeding age isn't just the way we're programmed to think about stripers.

Discuss...

spence
04-05-2006, 08:04 PM
I remember Frank D. writing about this, although I'm sure there's no scientific backing.

Given that that according to studies the serious egg production ramps up at 8-12 years, I'd wager that the impact of the kept 40 pounder and up is small given the relative numbers of those sized fish.

But she still could be a breeder, who knows :huh:

-spence

tattoobob
04-05-2006, 09:08 PM
Pete I am going to ask the Biologist at the Mass Marine fisheries, and I will post his answer as soon as he emails me back.

Striperhound
04-06-2006, 05:35 AM
Here is a thought starter. If a 40 pounders eggs are less viable does that 40 lb fish have better genetics therefore fewer eggs reach adulthood but have a better chance at being the next cow????:musc:

MakoMike
04-06-2006, 06:26 AM
I'm sure if you dig through the scientific papers from the ASMFC and the American Fisheries society you can find that data you're looking for. IIRC fecundity starts to drop off at around the 45 pound mark.

beamie
04-06-2006, 06:47 AM
I asked a similar question a lond time ago and Bassbabe who is employed somehow in the biology field gave this response, no numbers but it is info.

Quote:
Originally Posted by beamie
Does anyone know what the best breading fish is? i.e. When people get bent out of shape when 50+ pounders are taken do those big old fish still produce or not. Are they like humans where after a certain age it just doesn't work anymore?


It all boils down to reproductive potential and fecundity. Fecundity is the number of eggs a female fish produces. The larger the fish, the more resources it can allocate toward egg production. Therefore, the largest fish lay the most eggs -- and they don't go thru the 'pause. But although a 50 lb-er may lay more eggs in one whack, it has lower reproductive potential, as it is not expected to live for a heck of alot longer. Reproductive potential is the potential number of offspring a fish can produce in its remaining lifetime. So...a younger, smaller fish has greater reproductive potential, assuming it will live for many more years, grow, and make more babies each year. So don't feel guilty taking the monster fish...think twice about keeping the 28 inchers, because they're the ones with many years of breeding and tons of striper babies in their future.

baldwin
04-06-2006, 06:56 AM
Those huge cows may have a smaller percentage of viable eggs, but if they're producing a greater volume of eggs, that may, at least partially, make up for it. Secondly, if even a few of those eggs survive to produce a couple of more fish with those superior genetics, I believe it's worth it. Enough of those excuses to take the best fish out of the gene pool. If you have to kill the fish and show people that you can catch them, you're fishing for the wrong reasons. Give it up and buy some golf clubs.

MakoMike
04-06-2006, 08:13 AM
Those huge cows may have a smaller percentage of viable eggs, but if they're producing a greater volume of eggs, that may, at least partially, make up for it. Secondly, if even a few of those eggs survive to produce a couple of more fish with those superior genetics, I believe it's worth it. Enough of those excuses to take the best fish out of the gene pool. If you have to kill the fish and show people that you can catch them, you're fishing for the wrong reasons. Give it up and buy some golf clubs.

Why on earth would you think that a older bigger fish has "superior genetics" to a smaller young fish? That's like saying your five year old kid won't grow up to be six feet tall because he's only 3 feet tall right now.

Flaptail
04-06-2006, 08:16 AM
Why on earth would you think that a older bigger fish has "superior genetics" to a smaller young fish? That's like saying your five year old kid won't grow up to be six feet tall because he's only 3 feet tall right now.


Mike, that was dead nutz right on!:kewl:

JFigliuolo
04-06-2006, 08:19 AM
Mike, that was dead nutz right on!:kewl:

I think what you CAN say is that it is KNOWN the big cow has solid genes. The smaller fish's genetic disposition is unknown. We KNOW a cow has the potential to be a cow given that, well, she survived to get to be a large fish. The smaller fish, MAY, I STRESS MAY, be inferior. It MAY also be a true giant waiting to grow. It's just an unknown.

Mike P
04-06-2006, 08:28 AM
Also, I don't think that 40 pounds is a really good benchmark for determining that a striper is some sort of Uberbass with superior genes. Luck plays a big part in a fish growing that big--if that fish was 6" to one side when it was a schoolie, the osprey might have snatched it instead of the one it did--genes or no genes. What the hell do genes have to do with avoiding getting encircled in some North Carolinian's haul seine? Basically, I think any female bass is capable of growing to 40 pounds.

Maybe when you get to 60 pounds, you have a case for superior genes.

RIROCKHOUND
04-06-2006, 08:30 AM
Agreed Mike...
alot of it has to be luck of the draw

Pete F.
04-06-2006, 08:41 AM
I digress slightly but size is largely a factor of genetics. Ya got your big dogs and your small dogs, whitetails with big racks and small racks, guys with big...
Ya I was gonna say heads
I think once you find the information about fecundity you could graph it and figure out which size bass has the least impact if you keep it, but I just keep a few to eat. I fish mostly in Maine so they are around 2 feet thats the slot limit.

Pete_G
04-06-2006, 08:44 AM
Of course I can't find them now, but I've read several articles that were pushing the idea that we are changing the biology (making the adult size smaller due to un-natural selection) of some groundfish that have been agressively fished over the years.

So, the concept of eliminating the biggest breeding fish resulting in smaller adult sized fish isn't foreign by any means.

Also, BassBabe's info is interesting. Her post is implying that a 50# fish's eggs aren't any less viable then a 30# fish, just that her reproductive potential is lower. This by itself contradicts "common knowledge" of striper reproductive nature. While we're questioning things, what is a natural end to a stripers growth? Just because 60's aren't common does that mean they're old? Or are they just uncommon because of all the fishing pressure?

This is good, some real info. I think there is a LOT of misinformation and misconception out there. We should have real facts about the resource so we can be happy with the call to keep a fish or send it back when we're fortunate enough to have a large fish at our feet.

I don't like the idea of some groups making us feel guilty for taking a large fish if there is no reason too, nor that others push the idea that taking them all won't effect the resource. Reality would be good and probably it's a combo of the two.

Clogston29
04-06-2006, 09:00 AM
There are so many factors that I think it would be almost impossible to figure out. You'd really need to know the egg production for bass in each size range; the probablility of that fish surviving and reproducing for one, two, three, etc. more years; the release mortality for fish in each size range (I would assume that it is greater for larger fish but I have no way to know). When it comes down to it, keeping any fish has an adverse effect on the population. Catch and release even has an adverse effect on the population. However, if it wasn't for recreation fisherman stripers and many other species may have already been wiped out so recreational fishing is both good and bad for the target species. I don't think that anybody needs to feel guilty about taking a fish here and there, reguardless of size, because most of the factors that I've listed above probably balance out as long as there is no waste. I don't agree with encouraging people to keep more than they may need, however, and that's where the OTW Cup went astray IMO. Its difficult, if not impossible, to have a conservation minded tournament for a fish that cannot be kept in a livewell for later release.

MakoMike
04-06-2006, 11:37 AM
The other thing some of you guys are forgetting is the other half. That big old cow, or young going-to-be cow only carries half the genes of the next generation. And since spawing is random with males and males rarely grow bigger than 36-40 INCHES, how are you going to figure how to protect the futures cows' fathers?

jkswimmer
04-06-2006, 03:41 PM
I think genetics plays a large roll in ultimate potential this has been seen in trout habitats. If only the largest trout are taken out of a particular stream the result will be a stunted population. this the resson hatterary trout do not grow large, no survival of the fittest. Another way to look at it is why don't all people grow to six feet tall and three hunred pounds.
Something else I read at one time was that striped bass do not age as we know it. They can live almost indefinitely and were being studied for this.

Pete_G
04-06-2006, 07:47 PM
I think genetics plays a large roll in ultimate potential this has been seen in trout habitats. If only the largest trout are taken out of a particular stream the result will be a stunted population. this the resson hatterary trout do not grow large, no survival of the fittest. Another way to look at it is why don't all people grow to six feet tall and three hunred pounds.
Something else I read at one time was that striped bass do not age as we know it. They can live almost indefinitely and were being studied for this.

I've often eyed striper populations from the same view. I grew up fishing for largemouths and trout so right or wrong, I view our effect on them from a freshwater perspective, i.e. if you remove the big ones you get a stunted population.

Also, I really want info on what an "old" striper actually is. Fish aren't mammals and sometimes I think we view the way they age in that way. Do fish when they get old have heart attacks? Develop cancer? Besides predators and us, what kills bigger stripers?

I wish I stuck with marine biology instead of switching majors sometimes...

beachwalker
04-06-2006, 11:15 PM
Those huge cows may have a smaller percentage of viable eggs, but if they're producing a greater volume of eggs, that may, at least partially, make up for it. Secondly, if even a few of those eggs survive to produce a couple of more fish with those superior genetics, I believe it's worth it. Enough of those excuses to take the best fish out of the gene pool. If you have to kill the fish and show people that you can catch them, you're fishing for the wrong reasons. Give it up and buy some golf clubs.


but I like golf ....?