From: viking@iastate.edu (Dan Sorenson)
Subject: Re: Self Regulating Populations
Organization: Iowa State University, Ames IA
Date: Sat, 22 Aug 1992 00:38:07 GMT

In <BtCs4w.zD@wpg.com> russ@wpg.com (Russell Lawrence) writes:

>Let me rephrase the point I made previously:  Wolves typically remove
>sick and aging members of the herd.  In the process, they reduce the
>threat of disease.  However, it's food supply, not predation, that 
>limits total population in natural, stable environments... contrary
>to a popular hunter myth.

>As you say, however, we still have some major problems and the natural
>regulatory mechanisms don't appear to be working.  The truth of the
>matter is that the natural regulatory mechanisms are working, but
>they're not working effectively because the environments are unstable.
>This is especially true in your state, I believe, because of forest
>management practices that bring about feasts followed by famines.  Coupled
>with hunting, some of these practices actually increase fertility, and 
>thereby contribute to the overpopulation problem.

>tr> I imagine the reserves were free from human intervention.  But I also
>tr> suspect that that there was no predation (by hunters or other natural
>tr> predators).  It is the complete lack of predation that is the problem.

>So says the hunter myth.  If you think about the myth critically, 
>you'll discover that it's proponents somehow believe that natural 
>predators can outmatch their quarry the way humans with guns 
>might do.  The empirical evidence shows, however, that the 
>defensive skills of healthy deer are a good match for the 
>offensive skills of their traditional predator (wolves).  Apart 
>from the empirical evidence presented by Mowat and others, the 
>hunter myth falls apart logically when you ask yourself what 
>prevents predators from simply killing and consuming all the 
>prey.  Surely they don't take a census of the available deer and 
>limit their "harvests" the way humans might do.  

	Predators are opportunistic, and that includes both animals
and the vast majority of hunters.  A lion stalking game is no less
opportunistic than the bowhunter sneaking to within ten feet to
deliver a killing shot.  The "myth" you espouse to disagree with is
correct -- food dictates the number of animals in the herd.  It
does that by lowering birth rates and by the starving of the
animals.  This, of course, makes them more succeptable to disease
and physically weaker, hence the predators cull out the least
healthy and life goes on for all concerned.

	You have failed to show that the food supply does not limit
by starvation in any circumstance, and this is what the "myth" you
claim has no merit takes into account.  Prove it wrong.

>It seems to me that we need to stabilize these eco-systems that we
>wish to preserve, and stabilization won't be possible as long as
>hunter advocacy groups continue to petition lumber companies and park 
>departments to maintain a large deer "harvest" from year to year.
>Personally, I think it's dishonest when a group campaigns for programs
>that will increase overpopulation (aka "harvests), while citing 
>overpopulation as a moral excuse for sport hunting.    

	Dishonest?  They admit to wanting high populations so they can
harvest more.  That's like claiming a lumber company is dishonest for
planting trees so it can cut them down again.  Rubbish.

>Perhaps you don't see a difference between human predation and natural
>predation but those differences do, indeed, exist. 

	Culling the stupid instead of the weak.  Big deal.

>If I'm not mistaken, the average age of deer in the United States is
>less than three years, yet deer don't reach their full skeletal maturity
>before five years of age.  If they were subject to natural predation
>in stable ecosystems rather than human predation in contrived ecosystems, 
>there would be fewer deer and they'd live quite a bit longer.

	I'd like to know how this statistic can possibly have any merit.
The average is three years?  Just how was this arrived at?  If it was
based on deer killed on the highways and by hunters, the simple fact
that the younger ones have had less time to learn how to avoid these
dangers would skew the results quite a bit.  If it was from people
trundling through the woods, don't you think the older animals would
have been in the next county rather than seen by these potential
predators?  There was a hunting show on recently, where a closed habitat
of several thousand acres is maintained for the express purpose of
growing large deer.  Hunters pay to hunt here, and everybody is happy.
This has been happening for at least a decade.  Recently, they found a
trophy buck that died of old age.  Even with the decade of hunting,
and daily work by the staff to maintain the habitat and check the
deer populations, this old boy had *never* been seen.  I wouldn't trust
that statistic you've provided any further than I can spit.

<Dan Sorenson, DoD #1066 |"There'll be angels on Ariels in leather>
<z1dan@exnet.iastate.edu | and chrome, Ridin' down from heaven    >
<viking@iastate.edu      | just to carry me home." -- R. Thompson >
< ISU thinks I need more education, which they provide for a fee. >