From: schwae@marcus.its.rpi.edu (Eric A. Schwartz)
Subject: Re: New Subscriber and a look on hunting
Organization: Rensselaer Polytechnic Institute, Troy NY
Date: Tue, 7 Apr 1992 06:56:24 GMT

In article <1992Apr6.123853.4818@ac.dal.ca> robinson@ac.dal.ca writes:
>In article <h=wtryf@rpi.edu>, schwae@marcus.its.rpi.edu (Eric A. Schwartz) writes:
>> In article <1992Mar31.164400.4679@ac.dal.ca> robinson@ac.dal.ca writes:
>>>In article <p9qtz8_@rpi.edu>, schwae@marcus.its.rpi.edu (Eric A. Schwartz) writes:
>>>> In article <1992Mar26.101119.4553@ac.dal.ca> robinson@ac.dal.ca writes:
>>>>>
>>>>>  Hint #3: It is a well known fact among hunters that deer who have 
>>>>>survived prior hunting seasons catch on to the begining of one very quickly 
>>>>>and become almost totally nocturnal.  Those who refuse to learn, and adapt, 
>>>>>end up on the supper table.
>>>>>
>>>> Once again, you say you are selecting for a trait totally unnatural to
>>>> deer.  Being active at night hurts their breeding performance by 
>>>> restricting their hours, and wastes their already limited energy reserves
>>>> by causing them to miss out on the solar energy and higher daytime 
>>>> temperatures, thus increasing their thermal load.
>
>Not true.  Deer are most active at dawn and dusk.  They're normal dormant 
>time is from about midnight-1am till shortly before dawn.  They normally 
>rest and move during the day somewhat as well.  Generally though they are 
>fairly nocturnal to begin with.
>
>Hunting preasure makes them less active during the day.  However, if a cold 
>snap triggers the rut, all that goes out the window and you are likely to 
>see deer at any time.  As well, deer show an uncanny ability to adapt to 
>the movements of their predator.  They know when most of these bipedal 
>creatures leave the woods (around noon) and so they come out and stretch.
>
Re-read your own hint #3.  You are the one who said they become "almost
totally nocturnal."  Are you wrong now or were you wrong then? :-)

Do you know they come out around noon because you don't leave at noon?
Wouldn't that mean you take a higher percentage of "smart" deer who
do learn to recognize that humans are supposed to leave at noon?

>>>Well, impairing their breeding performance is in line with one of the goals 
>>>of sport hunting, i.e. controlling population size.
>>>
>> Controlling population size, yes.  I still believe this is necessary.  But
>> damaging the health of that population isn't.  Especialy at the genetic
>> level.  Since the point of responsible hunting is to help the deer and
>> make them healthier, altering their behavior like that should be something
>> hunters would try to avoid.
>
>No one has been able to do anything but *assert* that damage *might* happen 
>so far.  :-)
>
Right.  Nor has anyone been able to deny it.  And I don't get the 
impression that anyone is watching out to insure that it does not
happen.  If such damage were occurring (and allow me to point out
yet again that I don't think it is), would that not constitute
grounds for curtailing or eliminating hunting?
 
>>>How is it that being more nocturnal 'wastes their already limited energy 
>>>reserves'?  How is it that their 'energy reserves' (whatever the hell that 
>>>means) are limited?  Being nocturnal simply means that they do most of 
>>>their moving about at night.  It doesn't mean that they live in caves 
>>>during the day, so how can you justify saying that they miss out on the 
>>>solar energy and higher daytime temps?
>>>
>> Deer eat food and store it as fat.  That is energy reserves.  Deer have
>> been shown to live on a very  thin line between life and starvation as
>> a normal part of their ecology.  This is even when food is available.
>> Thus the energy reserves are limited.  That is why  control of their
>> populations is so necessary.  Even a slight food shortage can kill loads
>> of them, and severely weaken the rest for the coming year, and all starved
>> fawns for life.  
>
>The possibilities and implications of winter starvation are one reason why 
>the hunting season happens when it does.  It reduces the population on the 
>land, thus making the limited food more accessible to those who survive 
>hunting season.
>
Right, and that's why I support hunting.

>> When deer sleep, they curl into a smaller shape, with less surface to 
>> lose heat from.  They let their body temperatures drop, so as to
>> expend less energy, and tuck in their noses to minimize heat loss
>> due to breathing.  If they are forced to be active at night, when
>
>They are always active at night.  See above.  They just become a little 
>less active during the day and a little more active at night.
>
That little bit may be a little bit too much.  As I said, they live on
a very narrow balance of energy.  So a little bit may be the difference
between helping and hurting the deer population.  As near as I can tell,
nobody is even willing to watch out for this.  Just a self-serving
assumption that it isn't happening.  

>> it is cold, they can't use those methods to save heat.  They must
>> sleep some time, presumably during the day if they are active at 
>> night.  With higher temperatures, the heat savings are proportionately
>
>They sleep at various periods, predominately midnight till shortly before 
>dawn.
> 
Their activities shift more towards night.  You said that.  So, something
shifts more towards day.  Or do they simply lose time on a certain
activity?  

You say now that sleep is relatively undisturbed.  Yet they are more
active later.  Wouldnt' that yield greater total active time, and
greater energy expenditure?

>> reduced.  That is why they lose out on the daytime.  They should be
>> active then, when energy losses due to activity would be less than
>> when it is colder at night.
>
>Undisturbed deer aren't very active during the daytime either, except 
>during the rut.  The mating season overrides their good sense. :-)
>
So disturbing them causes them to lose still more energy?

>>>And what exactly do you mean by 'increasing their thermal load'?  Either 
>>>you have some pretty fuzzy concepts here or you haven't expressed them very 
>>>well.
>>>
>> Heat loss is proportional to the difference in temperatures.  Deer, being
>> mammals, have a nearly constant body temperature.  So if a deer at say, 
>> 98.6 degrees, awake, and 97 asleep, is in a place when it is 0 degrees
>> during the day and -32 at night, it would have a  proportionately lesser
>> heat loss if its maxima and minima coincide with those of its surroundings.
>> In a mammal, heat loss (thermal load) accounts for about 80% (I forget
>> the exact number) of energy expended.  So small reductions in heat loss
>> represent fairly major reductions in total energy expenditure.
>
>Personally I suspect that mating activity puts a much higher drain on the 
>animals energy reserves than being a little more nocturnal does.
>
You'd be surprised.  Find a calorie counting table, and find out how much
energy is burned off by different exercises.  Add up every "activity"
you do during the day.  It is next to nothing compared to your caloric
intake.  Most of your energy goes to maintaining your temperature.

E.S.
Newsgroups: talk.politics.animals