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Walter & Group :
Here is an interesting set of answers from Gary Meyer who has ongoing contacts at the IGFA. I learned some things from this :-
Gordy,
First off... I have to admit that I cheated (big time) on this one! As you might remember, I have volunteered for years at the IGFA, so I have made quite a few contacts there. In fact, one of my best fishing buddies is currently very much involved with the IGFA, and he is a fisheries biologist. I always seek his input when IGFA or marine biology issues arise, so I did the same with your questions. Below I've copied (most of) his responses. I omitted his wise cracks...as they pertained mostly to my casting ability. I thought you might want to use his answers as the IGFA perspective. After reading some of his comments I get the idea that he may have been quoted in the article... so some of this might be redundant. I'm not sure if he wants to be quoted again or not, so lets just pretend that these are my answers ...
I'll check out the magazine article tonight.
Gary Meyer
1.) What is the weight of the current IGFA World record rainbow trout Oncorhlynchus mykiss) ?
48 lb
2.) Where was it caught ?
Lake Diefenbaker, Canada
3.) Was this a "genetically engineered" fish ?
Genetically engineered refers to using recombinant DNA to produce desirable traits in an organism. This fish could have been triploid, which is more accurately termed genetically modified. Triploids are created by subjecting the eggs to high temperatures during the maturation process, but some triploids occur naturally in the wild as well.
[GH] Thanks for letting us know this. I was not aware of the distinction between genetically engineered fish and genetically modified ones.
4.) What is the difference between a DIPLOID fish and a TRIPLOID one ?
Diploid fish have one set of chromosomes from each parent. Triploid have three sets and are thus generally infertile
.
5.) Can you usually tell the difference by looking at them ?
Not always. Some say that you can tell hatchery/triploid trout by their enormous girth and truncated caudal fins.
6.) Do you think that genetically engineered fish should still retain
the original scientific name of their natural counterparts ?
Genetically engineered: NO
Genetically modified (e.g., triploid): YES
[GH] This answer makes sense in light of your definitions, above.
One might argue, however, that to have genetically modified (triploid) fish listed along with non modified fish for record keeping purposes might not be the way to go. I think this might well prevent anglers who catch non modified fish from seeking record status.
7.) Genetically engineered fish can grow much larger than natural fish. Do you think they should be placed in a different category for IGFA record keeping purposes ?
Because they do not invest energy into gonadal development all energy is thus placed in somatic growth. So, yes some triploids can grow bigger and/or faster but I don’t believe this is always the case.
Organisms can display a wide variety of phenotypes (physical characteristics) for a single genotype. This is termed phenotypic plasticity. Introducing a fish to a non-native habitat can cause it to attain freakish sizes with accelerated growth rates. All this occurs without genetic modification. Just look at largemouth bass in California and Japan, where they were introduced.
[GH] Yes. I can see that point clearly.
8.) Can you think of at least one advantage to genetically altering fish species ?
Triploids (e.g., grass carp) can be used as biological agents to stop the spread of invasives. Because they are sterile, you don’t have to worry about them taking over.
[GH] Might triploid fish "take over" by competing for the available food source ? Also, I wonder if there is truth to William's statement that some of the triploid males are not sterile ?
9.) Do you know of any other species of fish which have been genetically altered ?
Trout, salmon, grass carp
10.) What do you think the FFF policy should be with respect to genetically altered fish ?
A fish is a fish is a fish. As my favorite IGFA maxim states:
“there are some aspects of fishing that cannot be governed by rule making. Angling regulations cannot insure an outstanding performance from each fish, and world records cannot indicate the amount of difficulty in catching the fish. Captures in which the fish has not fought or has not had a chance to fight do not reflect credit on the fisherman, and only the angler can properly evaluate the degree of achievement in establishing the record.
[GH] Counterpoint: While I can understand this as IGFA policy, the statement, "a fish is a fish is a fish" could yield the question, "Yes. They are all fish. But are they the same fish ?"
The comments on fish fighting ability make sense.
I was fishing for Black Marlin in Panama a few years ago, when a lady angler hooked and landed a marlin almost double the weight of the then current line class IGFAWorld record. She refused to enter the fish for record consideration . Reason : We saw that fish strike, then immediately leap and drop to the water lifeless !
11.) In recent years, the atomic and molecular structures of certain metals have been altered in the laboratory. Scientists have given these new names and a different place on the periodic table of elements. Should this logic be applied to the taxonomic (species) listing of these genetically altered fish ?
The biological species concept defines species as a group of interbreeding populations that are reproductively isolated from other such groups. If I’m born sterile or get a vasectomy so that I can’t breed offspring, should I get another species name?
[GH] Upon undergoing your vasectomy, you were altered ..... but not genetically altered. (you might even be able to reproduce again after an operation to reconnect.) Your DNA hasn't changed. The concept of identifying species by DNA might someday change the current species concept (?)
At this time, the biological species definition still stands, however.
12.) If I were to catch a genetically altered trout using my favorite fly in a pond which weighed 20 lbs., and then on the following day caught a 2 lb. natural trout on the same fly in a clear mountain stream, which one would deserve greater "bragging rights" ?
Again, I would point to my favorite IGFA quote:
[GH] I suspect most fly fishers would choose the natural fish . A personal matter.
13.) Without resorting to laboratory gene alteration, do you think the practice of releasing hatchery fish into the wild fishery will eventually change the fish gene pool ?
It really depends on where the brood stock are from. In the case of salmonids that exhibit fidelity to particular drainages, mixing brood stock from several drainages and then releasing the progeny has had very bad repercussions in the Pacific Northwest. In the case of salmon, physical reproductive isolation over the millennia in different microhabitats (streams) has resulted in substantial genetic differentiation between drainages. They can still interbreed, but releasing F1s from captivity has resulted in them going into random drainages and outcompeting native fish for mates. Over time this can disrupt the adaptive genes the native fish have evolved.
14.) If you answered YES to 13.), tell us the likely result.
15.) Do you think the ongoing practice of farming Atlantic salmon will have an effect on the natural fishery gene pool ?
Maybe.
I don’t know enough about the Atlantic situation
16.) Most of the laws governing the commercial take of ocean fish result in the taking of a high percentage of large breeders. The "undersize" fish are routinely protected. Do you think this will eventually result in alteration of the gene pool of the species biomass
It can. Heavy commercial fishing generally results in truncated age/size distributions resulting in a paucity of small fish. From an evolutionary standpoint, there is mounting evidence that there is a hereditary aspect to “largeness”. Large females don’t only produce disproportionally more eggs, they are also often better provisioned. This gives newly hatched larvae an edge on their cohorts and the environment.
17.) If you answered YES to 16.), then tell us what you think the likely result will be.
18.) Can you tell us about at least one species of fish which is being farmed with no apparent impact on the natural biomass of the species ?
Cobia look like a good candidate. They are a cosmopolitan species that exhibit very little genetic differentiation among populations. Therefore, if any brood stock or progeny escape, you probably wouldn’t get the disastrous effects that we saw in salmon in the Pacific Northwest.
[GH] That may be true. For one thing, cobia are not anadromous. The don't go up into fresh water to spawn, so their smolts are not affected by parasites or diseases which might be picked up as they pass through estuary fish farm pens as do salmon.
Incidentally, we have noted a precipitous decline in cobia numbers here in the Florida Keys. The current presumption is that this is due to commercial over harvest. This may or may not be correct. As with other salt water fish, it might be a cyclic event.
19.) Most steelhead fishers consider the true wild fish to be superior to a hatchery fish. They are technically the same species .... so what is the difference ?
You tell me. When I go to a strip club, sometimes I’m in the mood for a dusky hued woman and other times a fair-skinned blond. Is one superior over the other?
[GH] Again we get back to the IGFA position that, "a fish is a fish is a fish". Avid steelhead fishers, however, may well look at this differently.
20.) An anadromous fish just returning from the ocean fights a lot harder when hooked than a member of the same species which does not go to sea. Why is this so ?
I wouldn’t know. How could you quantify this?
[GH] I doubt anyone has tried to quantify. It is a perception based on the experience of many sport fishers.
I'm one of them. I don't, for example, need a calibrated wind meter to tell me the difference between a gentle breeze and a howling wind.
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