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Yep... In a lab, with no predators.
Not going to cherry pick data, I'll cite all of the findings, whether or not they support my conclusions. But it's common sense in biological terms. To make it overly simple: You have oviparous fish (let's say herring, cod, stripers) that often produce millions of eggs, with innumerable larvae... They get preyed upon, with the hope that one out of every million survives to maturity to breed again. Then you have the species that put a ton of energy and care into producing small amounts of large, healthy juveniles- generally ovoviviparous and viviparous, sharks & rays come to mind. The theory is that these larger juveniles have a better chance of survival as they're born larger.
So yes, in a controlled setting with no natural predation there was no difference in survival 25 days post hatch (DPH). But what about 50 DPH? 100? Study hasn't been done, so who knows? Striped bass don't metamorphose fully into juveniles until 33-35 DPH (Lal, Lasker and Kuljis, 1977), and I know from my own aquaculture days (albeit with different species) that that's when a high percentage of mortality can occur.
All I'm saying is that big fish make big babies that grow fast. There's no scientific record of a big fish being any less fertile than a smaller one... Which is what the original discussion was about. The graphs below show fecundity vs. weight. I'd rather have more of those big, fertile fish swimming around... in addition to those 20's and 30's that also pump out young.
One thing's for sure, it's surprising that such little research has been done on this subject.
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