Consider hearing as an example. Those of us who love
the bush appreciate its unique sounds. The plaintive cry of jackal
ushering in the African night, the haunting call of night jars or
the hair standing on end effect brought on by the sound of lions
roaring close by, elephant trumpeting and leopard sawing.
To lose ones ability to hear is a tragic loss for
one becomes cut off from so much that makes life worthwhile.
And what about going blind how awful that must be.
Our ability to see as with hearing is a very, very precious gift the
value of which often only becomes apparent when we lose it partially
or completely. Those who are deaf say they would gladly give up
their sight to hear and those who are blind are often heard to
remark that they would be willing to lose their hearing if they
could only see again. The fact of the matter is that to lose any or
part of ones sensory abilities is indeed dreadful.
Sometimes loss of hearing or sight is progressive.
My hearing is not what it used to be. After all my years of shooting
(mostly without hearing protection!).
I have lost some hearing especially in my left ear
and I struggle to hear high frequency sounds. As we get older many
of us end up having to acquire spectacles to read or to see at a
distance as visual acuity begins to wane due to natural aging
processes. Sometimes loss of a sensory faculty can be caused by
disease or by inheritance.
I recently came across an interesting case and
realised what effect it could have on ones hunting ability. I had
been conducting the tracking module as part of a bow hunting course
when I became aware of the problem.
One of the exercises given to students is to follow
a prepared blood trail for a distance of about 100m. Exercises begin
with an easy to follow trail with a lot of bright red blood sign
indicating an animal bleeding profusely from an artery and then
follow up exercises become progressively more difficult with
infrequent and tiny drops of blood sign.
Most students follow the first trail with ease and
arrive at the finish point within 5-10 minutes.
On this particular day I noticed one individual
half an hour he had made no progress at all but was ferreting around
aimlessly and not making any headway. I joined him and asked if I
could help. He replied in the affirmative. I took him over to where
the first splash of blood was that was easily visible and pointed it
out to him and told him to carry on.
A few minutes later he had made little if any
progress. Either the individual had no ability to track whatsoever
or else there was a problem. I took him to the next blood sign on
the trail once again easily visible and asked him to point it out
to me. He could not and then the penny dropped he was colour
This is a genetic visual defect which can manifest
itself in the person not being able to see certain colours in the
visible light spectrum.
The student was red green colour blind. What we
could see as a bright red colour against the background of green
grass he perceived as grey on grey and it was invisible to him and
hence his inability to be able to follow the trail.
Now the implications of this to the hunter are
obvious. He will not be able to follow the blood trail of a wounded
animal and will have to rely on a second person, guide or tracker to
red green colour blind will also make it difficult to spot wild
animals that have a rufous (reddish) colouration. An impala will
stand out starkly against a summer green or winter straw coloured
background to someone with normal vision but will be more difficult
to spot in a person who has a red green colour blindness defect.
Most herbivores are also red / green colour blind.
Hunters know how important it is to be able to track
a wounded animal from blood sign. We try our best not to wound
animals but being fallible human beings we do occasionally "botch a
shot" and end up having to try and locate a wounded animal.
When an animal runs off after having been shot the
hunter will always scout around the spot where the animal was last
seen to search for some sign of blood which will confirm that the
animal was indeed hit and will then look for the trail of blood sign
which in some instances might be quite profuse and in other cases
very scant, small and far apart, which will lead him either to
within sight of the quarry to allow for a follow up shot or to the
downed animal. We should also be able to follow up on wounded
animals by observing other sign such as tracks, broken vegetation
But the substrate does not always lend itself to
this type of tracking and this is where the contrasting colour of
red blood against a background makes things a little easier for
those that can see the colour red that is. If you are "blind" to the
colour red, tracking blood sign becomes a virtual impossibility. How
do you know if you are red / green colour blind? A Japanese
Cheney is a
wilderness trail leader, rated field guide instructor
and the author of many leading articles on the subjects
of tracking, guiding, bowhunting and survival. Cleve has unrivalled experience in wildlife management, game capture and hunting, both with bow and rifle.
Click here to visit his site
developed what are known as Ishihara charts which
help diagnose the defect. The charts to diagnose red / green colour
blindness are shown in Figure 4. If you are unfortunate enough to be
colour blind to certain wavelengths of the visible light spectrum
you will have to rely on someone to assist you when tracking blood
The lesson to be learned from this article? Give thanks every
day for the faculties that you do have.