Pond Boss Forums INTRO Questions & Observations inbread

I get a few fish for my pond every year by fishing different pond to keep the diversity up but I think i got a bad batch. I cought some bass for my pond and all were about 4". A few days later i was thinking about the bass in the pond i got them from. The pond is little and is never managed there is only bass in the pond and no big ones. I think the bass are inbreeding. Will these bass effect the size of my bass in the next few years?

This may seem like a dumb question but did you rub their tounge before you tossed them in your water? You didn't throw Spotted/Kentucky's in your pond on accident?

I expect they were just stunted from having too many without much to eat but each other. I have a pond that was initially stocked from something like that. They have grown nicely and are now approaching 3 or 4 pounds. In the source pond, there is still nothing bigger than 12 inches with big heads. I doubt that they will ever reach their full pontential but they have grown nicely.

Inbreeding depression occurs when an isolated population of fish that starts from a very limited number of individuals reproduces through several generations. The general idea is that each individual has some characteristics that aren't beneficial, either in the particular environment in question, or to the species as a whole. If the gene is recessive, it is more likely to pair with another recessive gene, from a cousin fish, yielding an expressed non-beneficial trait. If the gene is dominant, then there is less likihood that the fish with the non-beneficial dominant trait will be outcompeted by a fish lacking that trait.

That being said, stunting of fish populations is more likely an environmental manifestation, as opposed to an indication of a limited or low quality gene pool. The fish you stocked, if indeed possessing poor genetic variability now have your fish to breed with and non-beneficial or detrimental traits will leave the gene pool through simple competition.

You, as the angler, are truly the x-factor in the equation. If you are interested in genetic influences on your fish population keep in mind that you are the top predator and try to assess your impact. I wouldn't worry about inbreeding nearly as much as I would worry about my own influence on harvesting the best fish first.

I'm officially changing my name from Bruce Condello to "Thread Killer". :p

Bruce, please don't! This is the kind of information we need! I said it on another thread but you're helping us go from "Everyone around here knows" to "We're learning more about". Because of you and so many other knowledgeable people, we are all learning so much more about our lakes.

Thanks, Norm. A forum is a funny place where you can make a comment and then wonder "Does everyone out there think that's the dumbest thing they've ever heard?"

Here's something really cool. In the Mendelian theory of genetics the exact opposite of inbreeding depression is call "Outbreeding Enhancement". This is also known as hybrid vigor or heterosis. So our buddy, the striped bass hybrid has so many good qualities in the F1 generation because the detrimental genes don't have a match on the same allele as the other species they are breeding with so all those little nasty traits disappear for one generation.

If upper case "A" is the better gene and lower case "a" is the detrimental gene then there is a high liklihood in an inbreeding population that the little "a"s end up finding each other.

Example: Aa X Aa = AA, Aa, Aa, aa

This means that one fish in four has both detrimental traits and becomes less viable. In a population with many varied individuals, it is far less likely to see the "aa" expression because each individual has the poor or mutated genes at different points on the DNA strand. Actually the Aa's aren't very good for a population because their progeny will often have an expressed detrimental gene pairing. Theoretically the "aa" can pop up many times on one DNA strand in one progeny, each one making the fish less viable, ultimately making it a genetic junk heap.

Heterosis or hybrid vigor means NO matching "aa" for one generation so the SBH gets good disease resistance, good growth and the good looks of both parents!

Bottom line is, don't start your pond with two crappie.

Then everything would have crappy genes. :p

Nice response....took me a second to get it, though. :rolleyes:

Ok Bruce,

You got me. I need a simpler (horsey-duckie-pony) explaination of the above post. Pictures help. Make it easy.

BTW, I got the crappy joke right away.

It takes two genes to tango.

Bad genes need a twin to make a bad trait.

Your cousins are enough like you to create lots of matches.

Cousins=matches=bad traits

Don't marry your cousin

Don't stock two crappies

When you stock a new pond with fingerlings, why do you not end up with too many cousins? Or siblings for that matter?

Additionally, could I assume this theory to mean that tossing in a fish from another source is highly desirable as a general practice? IE - every chance I get, throw in a new fish caught somewhere else?

Oh geeze, you had to stick that picture in there, didnt you? I guess I asked for it, but now I am really terrified of inbreeding...

Brucile, nice and loose for a Tuesday night eh?

This is your day off right?

A knowledgable fish supplier will provide you with fingerlings that originated from multiple males and females to provide diversity. Also as a matter of practicality, production ponds wouldn't have just two parents because there would be a risk that one or both wouldn't survive to reproduce.

Adding fish from new sources would only be worth the effort if you suspected that all of your pond's fish came from a very few parent fish. Personally I like the idea of adding a little diversity, although I have absolutely no scientific data to support my hunch. It make me feel good, though.

Sunil,

Tomorrow is my day off so I'm enjoying a Jack and Coke.

One is plenty. I need energy to fish tomorrow!!

Bruce,

I was thinking in terms of a mature pond that had been stocked only once and now has (assumption) a limited source of "non-cousin related" breeding population...seems at some point inbreeding would kick in (assumption #2).

Even with as few as a couple of dozen original adult brood fish you would have "aa" matches at a low enough rate to be not noticeable. Random mutations are also occurring through time. This is probably where many of the undesirable traits came from in the first place.

If I'm not mistaken there are a few notable mammalian species that are pretty high-strung and have problems with disease resistance, etc. The speculation is that at one time in history the cheetah population may have been down to a critical few individuals, and consequently have really poor genetic diversity.

Yes Bruce, I was at a going away party for a friend tonight. Near the end, I had to have some Patron Tequila.

Peace!

Random Mutations. Missed that.

Never the less, I too think adding diversity through supplemental stocking would be beneficial. It seems (to me) that more genes in the overall pond may reduce the affect of non-desirable traits.

Have another J and C.

Unsure what the risk factors are from adding other fish...?

Peace!

'Gator,

Risks of what?

Introducing "something" unwanted; disease, poor quality (as mentioned in the begining of post), bubba bass ? :p

GOOOOOOOOD question. That's a Cody if I ever heard one. Parasites and diseases have to come from somewhere. Are you increasing the chances by bringing in fish from remote sources on a regular basis? Or are the organisms so ubiquitous that they appear and affect our fish because of opportunity? I really don't know the answer to that question. Bill????

Actually, my apologies. I'll bet that's been addressed in a different topic heading. I should search it first and/or start a new topic heading. It would be easier if the topics followed the same general ideas for future reference. I'll bet anything that Bill's hammered the parasite introduction question ad nauseum. He's so good about answering questions and then we reward him by asking the same question again and again and again.

wow! this forum is great! I ask a question and you answer the question plus expand on it till it almost turnes into an argument.

I love JACK & COKE!

By the way, by closely examining the fish before stocking them into the pond would reduce the chance of disease and infection of your fish in your pond. Ive cought bass with leasions and cloudy eyes so i never stocked from that pond.

Bruce :

I understand "basic" genetics from studies in college and subsequent reading . Also understood your posts above. However this thread has me uncertain of an answer given me by a fisheries biologist {head of the state hatchery} when I asked him a related question.

I was concerned that one pond with poor results {over populated bass among other problems} might need additional LMB genes as the original LMB and offspring had been in the 6 acre pond for 30+ years with no additions. I thought your cousin example was the answer. He said , and I never understood why , that fish genetics did not work that way. I did not ask him why and it is possible that he misundrestood the question. I went ahead anyway and added some new LMB { floridas to a pond with only northerns}.

He may have known that the fish which came from the state hatchery had enough different parents for it not to be a problem but I did not give him that info. He might have known or thought that a 6 acre pond population is to big to be isolated for fish purposes or that 30 years is to short a period for problems to arise. He did see the population as we did an electroshock survey. I have seen no deformed or inferior looking fish however that might not be visable.

So I now wonder how many parents are to few , how small a population is to small and how long before new genes are needed in an isolated population? Will the inferior genes {fish} die off from competition ? Or is this even a potential problem for most small ponds ? Inquiring minds want to know . About your pic.-- does that mean Charles is crappy or can he be excused as the result of two small "a" parents . Any thoughts or help would be great. ewest