population bottleneck?

[Baby_Girl]

I have searched the Shrimp Forum for 'inbreeding' and the general consensus appears to be that shrimp mating with their relatives does not result in decreased survival or fecundity, nor diminish desirable traits such as coloration.

So a related question I have that has not been directly addressed, is how harmful are population bottlenecks in shrimp breeding colonies? For example, my green shrimp breeding tank has only 2 males. My recently established yellow shrimp tank has the opposite situation with only 2 females. I will try to obtain more of both shrimp types, probably more to put myself at ease than anything else. But it's obvious that these colonies would become dramatically inbred rather quickly, not to mention they are starting with less genetic material from the get-go.

But how many do you all think is the 'ideal' number of shrimp to start a healthy breeding colony? I usually strive for at least 10, with equal numbers of males and females or slightly more girls than boys. Should I even bother getting more greens and yellows to round out my existing numbers?

[badflash]

People apply ideas to shrimp that really apply to much more complex animals. The only reason to use 10 shrimp vs. 2 is that most new populations of shrimp have a high loss rate in the first month and you want to have enough males and females to get your colony started.

These shrimp basically have NO genetic diversity to begin with. Nearly all of any given color have come from very few parents. As long as there are few poor genes to select from, inbreeding is not a problem. Inbreeding is a tried and true way to improve and concentrate good traits. It is only bad when bad genes are allowed to stay with the population.

[Baby_Girl]

The only reason to use 10 shrimp vs. 2 is that most new populations of shrimp have a high loss rate in the first month and you want to have enough males and females to get your colony started.... These shrimp basically have NO genetic diversity to begin with. Nearly all of any given color have come from very few parents.

ah, I see. Makes sense.

Thanks!