I hope this happens soon

[JLH]

Originally Posted by zimmy

If you could point me to any of those studies, I would appreciate. I would like to at least see a discussion of the math. The potential of the small fish you speak of is irrelevant once those fish can be harvested at 28 or 36". The drums lot that targets the 18-27" allows for maximum recruitment and increases growth rates within the slot due to lower competition,which results in more and bigger fish. It may not be intuitive, but it is in practice, supported by the science, and it works.

Originally Posted by zimmy

If you could point me to any of those studies, I would appreciate. I would like to at least see a discussion of the math. The potential of the small fish you speak of is irrelevant once those fish can be harvested at 28 or 36". The drums lot that targets the 18-27" allows for maximum recruitment and increases growth rates within the slot due to lower competition,which results in more and bigger fish. It may not be intuitive, but it is in practice, supported by the science, and it works.

You originally stated that killing one 40" fish was the same as killing three 28" fish. Starting from now and going forward assuming all fish reach the same age (say 20 years) the eggs produced by the three fish will far exceed the eggs produced by the one. The smaller fish are going to grow and produce more eggs and the larger fish going to die off first.

A slot limit may be the answer, or maybe not. My only point was that mathematically you are likely get a greater return over time with the three smaller fish.




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Posted from my iPhone/Mobile device

[zimmy]

Originally Posted by JLH

You originally stated that killing one 40" fish was the same as killing three 28" fish. Starting from now and going forward assuming all fish reach the same age (say 20 years) the eggs produced by the three fish will far exceed the eggs produced by the one. The smaller fish are going to grow and produce more eggs and the larger fish going to die off first.

A slot limit may be the answer, or maybe not. My only point was that mathematically you are likely get a greater return over time with the three smaller fish.

Posted from my iPhone/Mobile device
Posted from my iPhone/Mobile device

Only if you are talking about killing three small fish for every large fish. You are assuming the three fish make it to age 20. They won't so the argument is invalid. The math doesnt work the way you propose it. I would like to move on, but I think it is important for people to understand the science of it so if asmfc gets their act together and moves on it, the community understands the basics.
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[JLH]

Originally Posted by zimmy

Only if you are talking about killing three small fish for every large fish.
Posted from my iPhone/Mobile device

Didnt you made the post saying that killing one 40" fish was the same as killing 3 28" fish? I was trying to say that I disagreed with that statement and that I think mathemaically you are better off killing the one large and keeping the 3 smaller breeding size fish alive.

Agreed time to move on.
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[zimmy]

Originally Posted by JLH

Didnt you made the post saying that killing one 40" fish was the same as killing 3 28" fish? I was trying to say that I disagreed with that statement and that I think mathemaically you are better off killing the one large and keeping the 3 smaller breeding size fish alive.

Agreed time to move on.
Posted from my iPhone/Mobile device

Yes, that is what I was saying. In other words, you would have to kill at least three smaller fish to equal the loss of one large breeder. Add in the fact that maybe half of small fish are male, the equivalency is more like 5 or 6 small fish harvested has the same impact as one breeder. Plus the small fish grow faster whn there is less competition in the school.

The math is based on fecundity and recruitment. I am not making statements about what I think, I am reporting the scientific properties of population dynamics based on what I was taught and what I have read in scientific literature. If it has changed, I really would like to read those studies. There are hundreds of studies and I haven't read them all, that is for sure.

[JLH]

Originally Posted by zimmy

Yes, that is what I was saying. In other words, you would have to kill at least three smaller fish to equal the loss of one large breeder. Add in the fact that maybe half of small fish are male, the equivalency is more like 5 or 6 small fish harvested has the same impact as one breeder. Plus the small fish grow faster whn there is less competition in the school.

The math is based on fecundity and recruitment. I am not making statements about what I think, I am reporting the scientific properties of population dynamics based on what I was taught and what I have read in scientific literature. If it has changed, I really would like to read those studies. There are hundreds of studies and I haven't read them all, that is for sure.

Here is the question based on what you originally posted “Larger fish have dramatically more eggs. One dead 40 incher is like killing three 28"ers.”

Over the next 15 -20 years which of these two options has the potential to produce the most eggs?

a. Three females that are 28” today and will continue to grow
b. One female that is 40” today and will continue to grow

You try to keep adding new variables but if you look at it from a strictly mathematical perspective as the fish continue to grow over time the number of eggs produced by the three will far surpass the number of eggs produced by the one.

Since you asked to see the math here you go. Numbers taken from this study: Mass. Division of Marine Fisheries: Striped Bass - Species Profile

For simplicity I’ll use the same eggs per pound for the life of each group though in reality the numbers of eggs the smaller fish produce per pound will go up as they grow.

Group A: 12# striped bass produce 850,000 eggs (70,833.33 eggs per pound)
Group B: 55# striped bass produce 4,200,000 eggs (76,363.64 eggs per pound)

Age and weight progression from here:
Striped bass fishing length to weight chart

Year 1:
3x 28” (10# each) fish produce roughly 2,125,000 eggs
1x 40” (26#) fish produces roughly 1,985,454 eggs

Year 5:
3x 37” (20# each) fish produce roughly 4,250,000 eggs
1x 50” (50#) fish produces roughly 3,818,181.82 eggs

Year 10:
3x 46” fish (38.7# each) fish produce roughly 8,223,750 eggs
1x dead fish – no eggs. If by chance it’s still alive and an 80# fish it produces 6,109,090 eggs.

Based on the math at no point in time does the one 40” fish produce more eggs than the three 28” fish and as they age the gap becomes larger and larger (especially once the bigger fish dies).