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“Rambling
and Useless”: The Genius of Matt Tunno This interview took place over email with Matt Tunno, Boone and Crockett Fellow for the School of Forestry at the University of Montana, Missoula, in June of 2003. Matt Tunno passed away August 5, 2003, at a young age. The interview began as an exploration of trout strains stocked in Arkansas and reached a question and answer level shortly later. Q: Any idea how many varieties of rainbow and cutthroat are legit for angling and thus may have been stocked? I know a large minority of these fish are endangered or threatened and thus unlikely candidates for special stockings. A: There are literally hundreds of rainbow and rainbow variants that are stocked all over the country. The Kamloops rainbow is a popular stocker for lakes and larger rivers, because it grows to near steelhead size if the conditions are right. But I have no idea what they would be stocking in Arkansas- you'd have to ask your F&G department specifically about that one. Cutties are more limited as far as genetic strains are concerned- there are several dozen sub-species of Westslope Cutthroat and several dozen sub-species of Yellowstone Cutthroat, and that's all I know about (except sea-run cutthroat, which are closely related to both species, but I'm not going to delve into that right now). My guess is that although both species are endangered in most places, you can create broodstock for stocking purposes with less than fifty fish in a coldspring hatchery, and since the Westslope variety is the more hearty of the two, most southern F&G departments would select a sub-species of westslopes to stock in rivers where temperature or pollution could be a problem. My guess is they would use a strain like the Snake River Fine-Spotted Cuttie, or another hearty strain.
A: You're right in your geologic history- in fact, Missoula
MT used to be a huge lake that eventually broke out through the CLark
Fork and Pend D'Oreille rivers and dumped into the Columbia right after
the last ice age. Idaho was actually beachfront property for millions
of years while salmon and steelhead were genetically developing into the
seven current species we have today, and would have remained so if the
Cascade range hadn't shot up and created the majority of Washington and
Oregon. All rainbows are relatives of steelhead, which is why they retain
the mykiss species name, and all rainbows are landlocked steelhead- just
like all kokanee salmon are landlocked sockeyes. It's been shown that
although several prominent strains of rainbows were landlocked by landslides
or other ecological catastrophes, a certain % of steelhead stay in the
river where they were born, becoming residents and creating rainbow populations-
like wise, if you stock rainbows in a coastal stream, some of them will
migrate to the ocean, and return later to give you an unexpected steelhead
run. Q: Similarly, how do browns get to be different from rainbows? Different root stock of ocean-run salmon/steelhead as a base? Doesn't one of the coasts have salmon that die off every year and one have some that go back and respawn over and over? (I am well inland and very ignorant here.) Are our rainbows and browns long distance relatives of these salmon that do not die or something else? Any idea how far back their common ancestor was? A: The brown trout is not native to North America. No
matter what anyone tells you, until the hatchery explosion in the late
1870's, there was never a Brown on this continent. Brown trout and Atlantic
Salmon share the genus name Salmo, as opposed to Pacific salmon, Cutthroat,
and Rainbow, which are all of the Oncorhynchus genus. Browns are Salmo
trutta, and have about 50 sub-species, and Atlantics are Salmo salar,
and have several hundred sub-species. Although we can't be sure exactly
why the two species split, there is fossil evidence dating back thousands
of years that there were several species of sea-run browns in Europe and
scandinavia. Some of these obvoiusly took up residence in Northern European
Rivers, and became the resident browns we know of today. And, having worked
in a hatchery which raised both browns and atlantics, I'll be damned if
you can tell one fingerling from the other, although the adults vary considerably
in appearance from each other.
A: Char are as much a salmonid as a brown or rainbow.
They all share the Salvelinus genus, such as the brookie (Salvelenus fontinalis).
Dolly Varden, Arctic Char, Bull trout, and Brookies are the most prominent
members of this genus, and are most certainly of the salmonid family.
And yes, some of them can and do interbreed with other genuses (the brook
trout can breed with a brown, for example). It's feasible (although VERY
improbable) that a rainbow/brown cross could be created- but it would
have to be done under hatchery conditions, because they spawn six months
apart, so there's never a time under natural riverine conditions when
a female brown is on a redd and a male rainbow is full of milt, or vice
versa. Most genus crosses are sterile (tiger muskie being a prime example,
as well as the tiger trout), thus they will only be around as long as
both genuses continue to spawn and co-habitat the same river system. A: Yup- and the Golden is Oncorhynchus genus and mykiss species as well.
A: Grayling- Of the salmonid family, but the genus and
species are different- they cannot be classified as trout, although they
share many of the same characteristics. While still a salmonid, their
genus/species name is actually Thymallus articus, which indicates a significant
departure from the genetic structure of Char, Trout, and Salmon. www.geocities.co.jp/Colle...archE.html I'm not sure about what's going on south of the equator, but I do know that all of the resident and sea-run browns and rainbows and the newly introduced Chinook in New Zealand, South America, etc. were all stocked- they never occurred naturally there. There may be some other genus of trout/salmon that is native to those waters, but I don't know of any. Q: Time-wise, when did trout evolve as we know them? The Pleistocene like our warm and fuzzy friends all over the West, or earlier? What did the ancestral precursors look like? A: Very good question. Salmon are my primary research,
and the current species we have now began to emerge during the Miocene
epoch, about 5-6 million years ago, and that goes for all species within
the Oncorhynchus genus. They descended from multiple species (including
the six foot long saber-toothed salmon - I'd kill for a time machine )
Char are more difficult- there are at least two different evolutionary
lineages that have been traced. The first, which is the North American
brook trout and lake trout, show evidence of existence long before the
Miocene, potentially going back over 10 million years (but remember, the
Eastern part of the continent is much older geologically than the west-
the Appalachians at one point probably stood as high as the Cascades,
but due to the second law of thermodynamics - everything moves from a
state of low entropy (chaos) to high entropy, they eventually eroded to
the much smaller mountains they are today. Give the Cascades and the Rockies
15 million years, and most likely they'll look like foothills). The other
lineage is the arctic char (Salvelinus alpinus), Dolly Varden (S. malma),
Bull Trout (S. confluentis), etc. They evolved later, due again to the
fact that they are native to the British Columbia, Washington, Alaska,
Northwest territories, MT, etc. They probably came about in the Miocene
as well, but that's an educated guess- I'd have to look it up to be sure. Q: Any truth to the hillbilly myth that browns taste worse than rainbows by virtue of being browns? (I've never noticed but I kill very few trout.) A: No idea. My guess would be that they should taste better, considering that they tend to prefer sculpins and smaller fish for dinner rather than insects, and hence receive a more protein-enhanced diet. But I'm not a chef, and, like you, kill very few fish. The browns I have eaten out here don't taste much different than the rainbows. I think that it's really a matter of size as well- any 20 inch brown is going to be mealy, as will a rainbow, whereas a smaller (say 12 incher) fish will always taste better. Q: At some point, didn't rainbows undergo a name reclassification from Salmo genus to the current O. Mykiss? Why is that, did we realize they evolved out of the pacific? A: Yes- they were re-classified about 60 years ago (roughly)
from the salmo genus due to scientific evidence of their gentic heritage.
Until then, they were labeled Salmo irideus. Q: Salmon. Two highly identical species evolve separately in the Atlantic and Pacific, or some root ancestor way back when? How did they populate both oceans if we accept the not-crossing-the-equator-band thing? A: As I noted before, from the scientific info we have, there is no evolutionary lineage between Atlantic and Pacific salmon. Atlantic salmon are of the Salmo genus, and are more closely related to brown trout than to any species of Pacific salmon. Believe it or not, they are not that closely related. Q: What roughly are the odds against cross-species fertilization? Any remote chance for a nonsterile cross-fertilization other than the cuttbow? A: Tough question- most geneticists don't usually tinker
with what might end up to be an ecological catastrophe. But they have
artificially created rainbows that spawn in the fall in hatcheries, and
in several rivers (notably the Firehole, in Yellowstone, a headwater of
the Madison) rainbows do spawn in the fall, their timing being very close
to that of browns in the same system. Yet there is no evidence that a
cross between a rainbow and a brown in those streams. So my guess is that
crossbreeding has to occur under very specific conditions, and obviously
rainbows and browns cannot breed naturally together. This leads me to
conclude that no, these species are meant to remain separate- I'm sure,
however, that under hatchery experimentation, certain strange crosses
could be developed- but I'd also guess that they would be sterile) Q: Which species can interbreed and what to they create? I have cuttbows down. Browns/brookies? Rainbows/any char? Why do char seem more able to cross with Salmo genus than Oncorhynchus or whatever the hell it is? A: Oncorhynchus are Pacific fish- they evolved in tandem with the changing riverine, marine, and terrestrial changes that occurred geologically- that's what makes them so diverse (there are over 300 different strains of steelhead alone). The same occurred on the other side of the continent, with very different results, and hence those fish are genetically wedded to the waters that they evolved in. But you are right- char seem to be able to breed with many more species than any other salmonid. For example, there are naturally occurring crosses between browns and brookies (folks call them tiger trout, and they are rare and sterile), and bull trout can interbreed with browns, although bulls spawn in the springtime and browns spawn in the fall. They do occasionally interbreed, and we see a few of them here and there in Montana, but they are also sterile, and we call them tiger trout, too. (I think the "tiger" label is applied across the board for any mixed species, like the tiger muskie, a sterile fish that is the result of a nothern pike breeding with a muskelunge). But the Oncorhynchus genus seems pretty well gentically isolated- for example, the five species of pacific salmon spawn at similar times in certain pacific streams, but they never interbreed. Additionally, chinook and coho spawn in streams that maintain large spawning populations of dolly varden and bull trout, particularly on the Olympic Peninsula, and there is no evidence that they ever have cross bred with any char species, or with other salmon species. Q: Sabre toothed salmon: This leads to an interesting question. We definitely have good morphological evidence that prehistoric fish such as these are in *a* salmon family, that is, they look like them a whole lot, right? So, following up from the discussion of the separate developments of Salmo and Onchorynchus genuses, what makes us sure that this and other prehistoric "salmon" like it are actually salmonids at all? Another way of looking at this might be to say, what makes a salmonid in the first place? Can a non-char, pacific, or atlantic salmonid strain fish become a salmonid during a certain evolutionary epoch, then evolve a different way and leave the family? In the London Museum of Natural History there is a great display of the long-term evolutionary development of the ichthyosaurus, the big aquatic dinosaur. They have several millenia of this all scribed in rock, as the dinosaur developed from a slitherer to a vertical-fin short-stroker like a shark and back again. How do we know these prehistoric fish are even in the same family and are not precursors to, say, tuna? A: Although I'm not a geneticist myself, I know how
they operate. For example, we are now finding evidence in Africa that
something more similar to Homo sapien than to Homo erectus or homo habilius
was around nearly 160,000 years ago. Although the fragmented skulls had
to be put back together and it's not certain that this was the case, there
is no way to classify, due to the similar bone structure, such a find
as anything but the Homo genus. The same holds true for fish. Studies
of fossils of fish like the saber-tooth salmon reveal that they were anadromous,
had similar morphology to current salmonids of the region, had all the
same fins in all the same places, had very similar bone structure (salmonids
have two sets of ribs, while tuna and the like are easier to fillet because
they only have one). See, genetics requires alot of guesswork- there are
entire eons where you don't have fossil evidence of say a certain reptile,
but then it will appear as a slightly different species 3 million years
later. In that case, we might assume that it took a radical new form for
several million years (like your description of the London Museum exhibit),
or we might assume that we simply haven't been able to find the right
fossils. We could also conclude that it went extinct for one reason or
another, only to resurface 3 million years later as a slightly different
species (the complexity theory folks like that kind of stuff, because
it makes an induction case for things like autocatalysis). Q: Albino Trout, otherwise known as banana trout. There is a strain of very melanin deficient trout running around in Arkansas waters that are "yellow as a banana" according to a local guide, my source. He says a lot of people mistake them for golden trout (thus the earlier disagreement on whether goldens exist in Arkansas). Could this be a true albino, ie, a "white" trout? Or is it some strange genetic variant with flawed melanin producing mechanisms (or whatever passes for melanin in fish?) A: Albinos are solid white, with red eyes, and are the
genetic fluke you described- Although I woudln't call it a flaw, certain
species seem to carry a rare reccessive gene which does in fact block
melanin. This recessive gene is noted invariably more often in rainbows
than in any other trout species, so chances are if you catch a true albino,
it is a rainbow. This "yellow as a banana" thing has me puzzled.
Whatever fish your boy is talking about is not an albino. Does it have
markings of any kind? I highly doubt that golden trout could exist in
most Arkansas waters for very long, likewise the apache or the gila trout.
Plus, golden trout more closely resemble, in coloration, Yellowstone cutthroat
(with more distinct parr marks and no throat slashes) than they do any
member of the fruit family. *G*. Q: Long term post-present devlopment. Can we expect these strains of rainbows and cutts and browns and whatnot we humans have scattered all over the world to increase in diversity in their new environments? Could we have unwittingly introduced the Southern Hemisphere's top predator two million years from now? What is the time-frame on significant enough body change to result in new species classifications? A: First, I wouldn't worry too much about it- you can
always kill everyone of them by removing the dams (wink, wink). As for
the southern hemisphere, I'm sure we aready have introduced the largest
and most dangerous freshwater predators into New Zealand, Chile, etc.
But they also will provide a fopod source for larger marine animals, which
will keep the introduced salmonids in check. They will certainly change
slightly as each new generation adapts to the foreign ecosystem, But,
like a goldfish in a little bowl, they won't out grow the size of their
habitable environment. Q: There is a spring at Roaring River State Park that is essentially a giant waterspout that dives more than 225 feet into the rock. To what depth are trout able to survive? Could rainbows lurk down deep in the earth and only come out to feed at night? How deep do sea-run salmonids dive and feed and does their own body mass make a difference in this ability? A: In underground srpings, like the one you describe,
there are fish which head up into the spring and take up residence there.
Occasionally, you'll see fish that move and out as their feeding and shelter
requirements vary. Interestingly enough, though, in most cases like that,
there are year round residents in the underground spring which, after
only several generations, become completely blind and even stop developing
normal looking eyes. My guess is, you'd never see one of these unless
you unearthed the spring. Q: What are the primary salmonid predators when they are at large out in the Pacific. Any ideas how many never make it back due to natural predation? A: I could write a thesis on this one - This question
has to be broken down into several parts. If fish are born or hatchery-released
way above several hydropower structures (In Idaho, e.g., each smolting
salmon has eight dams to cross before it hits the estuary), unnatural
predators have been introduced in the warmer-mater reservoirs behind each
facility, so most smolts must first ward off small and large-mouth bass,
northern pike, walleye, etc as they try to find their way through the
reservior. If they are trucked from Idaho at the base of Lower Granite
dam down to the esturay, they risk disease, homing confusion, and, upon
them being released into the columbia esturary, literally millions of
tehm fall prey caspian Terns, because they undergo a two-three day re-orientation
period where they swim around aimlessly in large schools trying to get
their bearings. Once they enter marine evironments, they feed primarliy
on squid, shrimp, and will follow large schools of small baitfish for
hundreds of miles. Likewise, the Orca Whale and several species of Pacific
shark (including the Great White) will follow the schools of salmon around,
eating for entire winters off of the unlucky members of the school.
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