Do steelhead and salmon have memories of ancestral prey?

**AuSableTrophyhunter** · 08-19-2010, 02:23 PM

I have only fished the Great Lakes for steelhead and salmon. I wonder whether my fish which cannot go out to the ocean still have a genetic memory of food their ocean going ancestors eat? I read that UK fly fishers use salmon flies that imitate red squid or shrimp that ocean going Atlantic Salmon eat. I wonder if my Atlantics possess an imprint of squid and shrimp as prey even though such prey does not exist in Lake Michigan,for example?
And do mysis shrimp inhabit the Great Lakes?

**Duck-butt Chucker** · 08-19-2010, 03:27 PM

[quote author=AuSableTrophyhunter link=topic=4734.msg36886#msg36886 date=1282242205]
I have only fished the Great Lakes for steelhead and salmon. I wonder whether my fish which cannot go out to the ocean still have a genetic memory of food their ocean going ancestors eat? I read that UK fly fishers use salmon flies that imitate red squid or shrimp that ocean going Atlantic Salmon eat. I wonder if my Atlantics possess an imprint of squid and shrimp as prey even though such prey does not exist in Lake Michigan,for example?
[/quote]

Here’s a quick synopsis of the life cycle of a potter wasp:

“After mating has occurred, the female wasp builds what looks like a hollow igloo made out of mud, and sticks it on a wall or the underside of a roof. The mud is made of her own spittle, dust, and small stones. It’s quite a structure, about 1 cm in diameter, and 1 cm deep.   At the top, she creates an opening, and curves the lip of the opening backwards, much like the lip of a round ornamental vase. She decorates the nest with shiny pebbles.   She then catches and stings small green grubs.   She stings them - but does not kill them, merely inducing partial paralysis. This keeps the game fresh and not putrefying. Somehow, the wasp knows what sex her offspring is going to be. If male, she catches fewer grubs, and if female she catches more. But the egg is laid only after these same provisions are stored; and this egg has a determined sex, though even the most minute examination is not able to discover the differences which will decide the hatching of a female or a male but somehow the mother knows beforehand the sex of the egg which she is about to lay; and this knowledge allows her to fill the larder according to the appetite of the future grub.   The next question is where is the mother to lay her extremely fragile eggs? If she lays them in the mass of grubs, then they might squash it as they wriggle around so instead   the mother suspends the egg by a silken thread from the ceiling, out of reach of the grubs. When it hatches, it is suspended by its hindquarters, and can raise itself out of danger if a grub becomes too frisky.   She has also built an escape route for it, a protecting sheath that is almost undetectable to us because it is so well hidden.   Now wasps have a brain the size of a mustard seed. And yet, the mother is able to do all this - without having been taught - after all, she never sees her own mother, who dies after all the above is done.”   That being said…How can she possibly   know how to make mud?   know how to construct an igloo?   know which grubs to catch?   know exactly how much venom to inject, and where to inject it so it will paralyze, but not kill? Know the sex of her eggs before they hatch and the corresponding variance in food quantity they need etc….answer is all this information is all simply passed on from generation to generation of wasp through their genetic code so it is very easily conceivable the same type of knowledge in regard to food could be passed on from generation to generation of Salmon through their chromosomes as well regardless of whether or not they have actually ever encountered it beforehand

**Davyfly** · 08-21-2010, 10:39 AM

Ausable.

What we used in the UK is a prawn, which is same as we call shrimp here.
They are natural baits dyed red, orange and purple. Mounted to a prawn rig. And then fished through known Salmon lies and holding pools.
They are in fact now banned for some rivers or have a limited period of use for others.
They will also take night crawlers would you believe.

There are flies tied to imitate shrimp/prawns. The most famous called the General Practitioner, Usk Grub, Alleys Shrimp and many more.

Atlantics are a unique species.
When they return to a freshwater system from the ocean, they loose all teeth, the viscera, digestive tract more or less shuts down and is of no further use. Atlantics do not feed once in the rivers prior to spawning, after that is a different matter but this is also related to the length of the river.
They are known as Kelts after they have spawned. Unlike Pacific salmon Atlantics if they are not beat up return back to the ocean which is why we see 2nd or 3rd returned fish in huge sizes as much as 70 lbs.

In the case of short river systems odds are by the time that have run downstream, which can be as much as 50 miles a day they have not at that time developed the means to feed. But they take a fly or bait at times.
Rivers in UK and EU are generally short.
It is illegal to kill kelts or gravid fish.

On the other hand if you take a river like the Miramichi some 400 miles they will feed, which is a time many choose to fish for them.

It would be difficult to determine if land locked and hatchery raised introduced salmon and steelhead still retain the same traits as true wild fish, other than we know they still retain aggressive instincts toward lessor form of life, which are those they primarily eat, which is a natural instinct for survival of the species.

**AaronJasper** · 08-22-2010, 10:21 PM

That's a really tough one actually. Do you catch them on swung flies? My guess would be that if your answer was yes then you can assume that the Atlantic Salmon that you fish for exhibit some of the same traits of wild ocean going Atlantic salmon. The food this is weird because although I am not skinny by any means, I do not eat the same food as my grandma or grandpa. Now I know thats an exaggerated example, but I think that the Atlantic Salmon in the Great Lakes, since being exposed to such a different food base when compared to their ancestors that they can be almost and entirely different species due to the selective breeding that has gone on to create successful returns.

**Davyfly** · 08-22-2010, 10:56 PM

Aaron,

If any thing the raising of Atlantic Salmon, and other anadromous species has proved to be detrimental to the remaining true strains of genetic wild fish.
Many USFW hatcheries only adopt the policy of catching wild fish, retained for eggs and then the offspring returned. Sadly the percentage of fish that return is less than 1%.

In the case of the great lakes all salmonids were introduced, granted they may still retain the instinct to attempt to spawn. Survival is not considered to be a worthwhile factor, in consequence very large numbers are stocked to support the fishing industry.

It is also known that Atlantic escapes from farming activity has caused serious issues in so far as they have mixed with true genetic strains which by and large return to the rivers of birth.
Not a instinct of hatchery raised fish.

Interesting thing about Atlantics is that a male parr of the species is capable of fertilising eggs.
These guys would typically be parr from the previous seasons spawn that have never smelt the ocean. It takes around two years before the smelts return to the ocean.

Fly fishing for Atlantics is a very different deal to many other salmon species.
Interesting again is they will pick up a ledgered worm, take a prawn fished on a bobber. Spinner baits and the like.
Fly fishing can be at times a very frustrating issue even when you can see and know fish are present.
Sometimes it may take a 3ins brass hairwing tube or a size 10 or 12 trout fly size. they are a mystery fish that's for sure.
Each and every water will differ, depending on the amount of time the fish have been in the river, climate and all other factors.
Here again unlike Pacific salmon, Atlantics can remain in a fresh water environment for many months before they spawn and not eat. The longer they are the more difficult they are to catch.
DW

**AuSableTrophyhunter** · 08-23-2010, 10:03 AM

Aaron, I hooked one and lost him on the first immense leap on 5/28 on a swung fly. Later, with the heat wave I was dead drift nymphing tiny tan caddis. Normallly, I would have been using streamers. This has been a very bad year for me because of the heat.
This winter I will tie general practitioners, cascades and Allly flies to see how they work. I have not tried these patterns, opting instead to try to imitate the natural forage with subtle flies.

**Davyfly** · 08-23-2010, 11:50 PM

There are two flies that have for me caught many Salmon over the years.
A Lemon grey and Willie Gunn, both hair wing versions as single hooks and tube flies.
Alleys has also taken fish with a few other Irish style shrimp flies. these are typically tied on small trebles which may not be legal where you fish.

Davy.