A Bass's Sense Of Smell
By: Leo Watson
Not to very long ago few anglers knew that the black bass even
had a nose, let alone used it. Only recently has any attention been
given to the bass's sense of smell. How good is it? Research biologists
are still testing but the fishing industry has introduced a host
of effective bass scents. Bass fishermen just like us buy loads
A Bass's Sense of Smell is a Multi Million Dollar Business
It has been reported that annual scent sales are in the neighborhood
of $40-$50 million. More than 50 manufacturers have at one time
or another been marketing scent products. Scientific Bass Products,
Berkley, Normark and other manufacturers have jumped into the very
lucrative market. Each has numerous testimonials from biologists,
professional anglers, and weekend anglers who swear by their favorite
scent. This anglers choice of scent is Kick'n Bass. It is in this
pro's opinion the best on the market bar none! You are invited to
read this authors testimonial for Kick'n Bass at www.kicknbass.com.
It is testimonial #99 in the professional anglers section.
The Science Behind the Bass's Sense of Smell
While a great deal of research has been conducted on the olfactory
systems (sense of smell) of salmon and catfish, comparatively little
has been done on bass until recently. We do know that a bass's sense
of smell is not as keen as that of a salmon or catfish, but it is
much better than previously thought. It has been noted that bass
discriminate scent much better than even the best bird dog.
Any discussion of the bass's sense of smell should consider how
they use it, i.e., for foraging or protection and when. Bass use
their full range of senses especially when visibility is limited.
Smell becomes increasingly important in low light or muddy water
The bass's preyfish are composed of amino acids, the building blocks
of all protein and flesh. Each preyfish contains differing proportions
of amino acids. The injury of a preyfish and release of amino acids
into the water elicits a searching behavior from the bass. This
is one reason why scent products with amino acids are attractive
Tests by bass researcher Dr. Loren Hill show that bass can detect
a preyfish odor source at a distance of 25 feet. Only the bass's
sense of hearing (which is my next article) is capable of greater
range under normal water clarity conditions. Dr. Hill also points
out that the bass exhibit a snakelike swimming action when honing
in on an odor source.
A bass has a pair of nostrils, or nares, on each side of its head
between the eyes and upper lip. Each nostril has two openings separated
by a bridge of skin. Water does circulate continuously through these
short passages where microscopic, hair like cilia detect odors.
The water passes through the nostrils without entering the throat.
As a bass swims about, water movement is enhanced and the nostrils
are constantly in use. A membrane tissue, called the olfactory epithelium,
consists of complex folds that line the nostrils. This membrane
greatly increases the total surface area and the bass's receptive
Within the epithelium odor molecules activate millions of olfactory
receptor nerve cells, these send a message to the olfactory centers
of the bass's brain where the odor is interpreted.
As a bass ages and grows larger, the number of olfactory folds
increases. It has been found that young 4 to 6 inch largemouth bass
have 5 or 6 folds. A 12 inch bass may have 10 folds while one 20
inches in length may have as many as 20 folds. It has also been
found that the diameter of the olfactory organ itself grows with
age. Most scientists conclude that older bass have a better developed
sense of smell.
In concluding this article anglers must realize that to catch bass
you must appeal to their senses. Their primary sense is sight however,
if they can't rely on their sight we must be prepared to appeal
to their other senses. The successful angler will use scents to
his advantage to appeal to their sense of smell as well as to cover
up human odor. One tactic I do use with the scent to mask my human
odor is to apply scent to my fingers and rub it directly to the
first 4 or 5 feet of my fishing line. This is especially effective
when flipping or pitching.
This is the second in an ongoing series of articles to help you
better understand how the bass's senses work. The greater your knowledge
of a bass's senses become, the better your chances are of boating
more fish. Keep checking back on this web site for my next article
the Sense Of Hearing. If you have any questions or comments about
this article please feel free to contact me. Remember always take
a kid fishing. You are helping to ensure the great sport of bass
Pro Staff - Contact me with your questions or comments at