Re: NANFA-L-- Old story, new twist? Old twist new story
Mon, 15 May 2006 13:21:45 EDT

Ok, I know all you guys know I am a sturgeon nut but no I wouldn't release
ten thousand predatory Chinese paddle fish even if they were available without
permission from heads much smarter than mine. (I might do my best to
convince who ever is charge that the two smallest sturgeon species should be
released in the Poca River, but that is another argument.) On the other hand in the
Mississippi River we do have a great river system that is starved for
ecological specialists. I love the Amazon, mostly because of the incredible variety
of fish and other animals that inhabit it's waters. Many of these fish
compete for the same food and space as the others do, surviving by tiny differences
in some part of their survival strategy. The Mississippi doesn't even come
close to the diversity of most big tropical rivers around the world. Lets face
it, the Mississippi has a definite disparity of fish along with it's lack of
diversity. We wild wonderful humans have done our absolute best to destroy
what diversity the Mississippi had to begin with but the disparity of the life
forms comes from it being a basically cold water river. Yes, we as humans
can rase both the diversity and reverse the disparity of the life forms in the
Mississippi. I know most of NANFA-in-this point think I am league with the
devil or have lost my mind or something similar but lets as a group turn this
into a thought experiment. Much can be learned from thought experiments. How
would we raise the diversity of the Mississippi, increase the disparity and as
much as possible preserve what little native live is still there? First let
me say that much of the fish we hold dear, even many of the bigger ones make
most of their living in the smaller tributaries of the Mississippi. The large
main channels are pretty much limited in the numbers of species that spend
most of their time there. This is with good reason, food resources in the main
channel are probably limited to carp in the 2 pound plus category (maybe we
do need the Wels catfish from Europe, two pound carp being it's main food
source) and large catfish waiting until dark so they can move into shallow water
to dine on smaller fishes and crustaceans. As the river gets smaller in it's
tributaries the diversity of fishes becomes more abundant but the disparity
of fishes pretty much stays the same. I want to put forth that the really
small tributary might contribute to the survival of many fish that would be
eaten into extinction if not for these small stream refuges. As fish such as
suckers breed and crowd out each other the bigger fish migrate to the larger
rivers where they can survive due to their size, possible going up stream to
spawn but living out their lives in the bigger streams where they don't have to
compete with smaller versions of their own species. Small rivers that run into
larger rivers that run into even larger rivers before becoming part of the
mighty Mississippi might be the back bone of the rivers diversity, such that
it is. The Mississippi is a very large river system and as such can support a
large variety of fish. Unfortunately these are all fish that are closely
related to each other and in a million years they will still be closely related
to each other. In other words the disparity of the fish in the Mississippi is
unlikely to change on it's own. Of course we have helped a little bit but
even a carp is still distantly related to fish that are native to the
Mississippi. So as a thought experiment lets think about how we could change this
disparity. Are there fish that are different and adaptable enough in form to raise
the disparity of the Mississippi. The Chinese paddle fish, predator that is,
would change the diversity and possibly contribute (or take away) from the
river but it wouldn't really change the disparity. A population of Chinese
giant salamanders that could actually compete with the other animals in the main
river would raise the disparity of the river. Freshwater dolphins would
raise the disparity as would freshwater stingrays. Dwarf alligators would just
raise the diversity and since they would range further north than American
alligators they would be cool to be sure, but no brass ring. Since there are no
totally freshwater sharks bullsharks do not count (but maybe with a little bit
of genetic engineering we could have small nurse sharks, sawfish, and sting
rays in the cool Mississippi waters). Actually there is evidence that cool
water rivers support less fish in diversity and the disparity of these fish is
very low. Lets say that some unimaginable disaster rendered the Mississippi
lifeless. Could we bring back the river with a diversity and with a disparity
of organisms on a par with tropical rivers? Lets face it introduction of non
native life forms is one of the things humans do best, right up there with
killing off native animals every where we go as a species. I think it might be
interesting to see just how diverse and how high the disparity of a major
river system could be made by humans if we really wanted to so. I know that many
of you think this is a waste of time but we just might learn something about
how an ecology is put together and how complex such an ecosystem can be made.
Sadly most of the animals that would raise the disparity of the Mississippi
are almost to a species tropical, there is even a species of freshwater horse
shoe crab but it too is tropical. I know most of you have real lives and
this thread seems pointless but lets keep this thread going, it doesn't have to
be the main topic of discussion every day but I will keep track of the ideas
we as a group come up with so we can do some caparison with the Amazon, the
Congo, the Nile, or any other tropical river. At the same time we might learn
a little bit about the cool water rivers of the world and how they compare
with our own Mississippi in diversity and if the level of disparity is really
as bad as it looks.

Michael Hissom
aurea mediocritas
Oh! Oh! Oh! My first entry is the freshwater seal! Can you imagine the
Mississippi with seals hauled out on floating logs sunning themselves!!
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