Subject: Re: NANFA-L-- Re: madtoms (was review of suckers ...... )
From: Crail, Todd (farmertodd at buckeye-express.com)
Date: Tue Oct 12 2004 - 13:48:42 CDT
----- Original Message -----
From: <dlmcneely at lunet.edu>
> But bass do eat them. Food habit analyses of smallmouth in Ozark streams
shows that they eat no small number.
I don't doubt that for a second, nor was I ever claiming that predation
wasn't a factor against success. But to get into the essence of what I was
For a critter that spends a great portion of its life buried under rocks...
Predator-free living space within the niche (all your feeding and breeding
resources are met) comes at a premium, and is pretty much what can make or
break the survival of an individual. So an individual who is better at
competing with its own species will have less chance of getting knocked off
by a predator because they will select the habitat that fulfills their niche
best with the least amount of external hazzards.
If you don't make that kind of selection up front (like at a hatchery),
you're placing more individuals in an unnatural distribution at a size class
or year class. Which, if they're all equally effective at exploiting a
niche, having skipped the earlier bottleneck, there may not be enough
resources to support ANY of them at the next level.
Lets say I have a prison with 100 individuals. I have 2 steaks, 2 loaves of
bread and 2 dinner salads for the whole population each day. Can 1 of those
individuals survive on that amount? 2? How about 25? At what point in the
fight for a piece are they all going to perish?
And back to predation... Would you shop at a grocery store that had a sniper
on the roof, or one where they have a "sniper proof" guarantee? You know
you'll have to pay more for food at the guarantee grocery, but would it be
worth it to spend some of your resources to assure you don't get shot at?
If you had a greater percentage of the local economy's money than your
fellow grocery shoppers, I wouldn't doubt you'd spend it on safe food
It also doesn't suprise me that they've taken off quickly in Abrams Creek.
The total and complete annihilation in the 50's left plenty o' open
spaces... And resources that were under used until the reintroduced
component came back. I think once they've gobbled up the open spaces,
you'll see a decline, and then the population will begin to bounce too and
fro according to abiotic conditions, but in a much more stable pattern than
when they're exploding back onto the scene.
Again, I'm only using madtoms as an illustration of the concept. It would
get waaaaaaaaay more blurry with a pelagic animal, and that's why I took the
opportunity to talk about this. Of course, I do realize that I type in
cryptic thoughts that seem only to read correctly to me... But I should at
least try ;)
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: Fri Dec 31 2004 - 11:27:44 CST