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Exploding The Myths With Some Truths About Lure Color
By: Greg Vinall
The day had been slow. For the fifth or sixth time I steered the canoe
close to a rocky dropoff on the Hopkins Estuary and enjoyed the gentle
drift afforded by a light breeze that was running parallel to the shore.
It wasn't the best day for fishing, in fact I hadn't raised any
piscatorial interest at all. It was bright and warm with plenty of boating
traffic to create a disturbance in what is essentially a fairly small
waterway. Perhaps if I'd been prepared to soak baits quietly in a deeper
hole or under the shade of some overhanging vegetation I might have done
better, but that would have been giving in. Instead I persisted in
flicking small crankbaits at any rocky structure I could find along the
steep foreshore.
I started trying to convince myself that I was happy just to be out here
enjoying nature, the warm sun on my back and the song of a whistling kite
overhead. Without really thinking about it I made yet another lure change,
this time from a pink and yellow pattern with a black spot amidships to a
small black deep diver with just a hint of silver scales. I deftly flicked
the little lure into a small pocket behind a large rock, gave it a second
or two to sink, then cranked over the little Chronarch baitcaster, gave
the lure a couple of gentle twitches and idly began my retrieve. Whack!
Two turns of the handle was all I managed before the lure was nailed by a
stud black bream that proceeded to go berserk in only two feet of water.
No real thought had gone into that lure selection. In fact, there had been
no sign of fish for so long that I barely thought at all, I had just made
yet another random lure change. Yet, I immediately attributed my change of
fortune to having stumbled across the particular color combination that
the fickle bream happened to be hammering on that day. But was it really?
Or was it the rattle in the lure that did the trick? Or perhaps it was
merely the sound and vibration afforded by the size, shape and action of
the lure. Maybe I just happened to lob a lure right on top of the
unfortunate fish, which was in a foul mood and responded angrily to being
so rudely disturbed.
The truth about color
Like most anglers, I like to have plenty of color options in the tackle
box from which I make my choices on the day. Also like most anglers, I
probably put far more emphasis on the influence of lure color and the
intricacies of lure finish than logic should allow. As one old-timer once
told me "…them finishes are designed to catch fishermen, not fish".
Lure color definitely plays a role in eliciting strikes from time to time,
but let's look at the issue more objectively. I know that plenty of
experienced anglers will want to take me to task on what I'm about to say,
so for the purposes of the next few sections I'm going to immerse myself
only in undisputable scientific fact and stay away from the subjective or
anecdotal. Bear with the technical talk, I'll make it as simple as I can,
and at the end we'll get to the really interesting stuff - how all this
should influence our choice of lure color.
Let's begin our analysis with a (very) rudimentary physics lesson. Most of
us would be aware that white light is made up of many different colored
lights (wavelengths). When light strikes an object some wavelengths are
absorbed and others are reflected. It is those wavelengths that are
reflected from the object that reach our eyes and are interpreted by our
brain as color. Objects that appear white to us are effective at
reflecting all of the visible wavelengths of light
(Figure 1).
Figure 1: Diagram showing the various wavelengths of light and
those that form the visible spectrum.
Conversely, objects that absorb all wavelengths and don't reflect any
appear to us to be black. Between the extremes, most objects absorb some
wavelengths and reflect others and appear to our eyes to be colored. The
color we see is the combination of all reflected wavelengths. For example,
when white light strikes a leaf, most of the visible wavelengths of light
are absorbed, but the green ones are reflected, making the leaf appear
green (Figure 2).
Figure 2: Some wavelengths are absorbed off objects we see, others
are reflected. It is the reflected wavelengths that are interpreted by our
eyes as color.
Color visibility at depth
When white light passes through pure water the various wavelengths are
absorbed at different rates. The long wavelengths (reds) are readily
absorbed by the water molecules while the shorter ones (violets) are
absorbed at a slower rate and penetrate further into the water. Put
simply, what this means to Joe Average who likes to spend his weekends
trolling or casting lures is that some lure colors simply aren't visible
to a fish that is deeper in the water column.
The longer wavelengths (reds and oranges) are absorbed nearest the
surface, so at depth there aren't any of these wavelengths to reflect off
the lure. All other wavelengths are absorbed, so that color on the lure
appears to the fish to be black, or at best may appear weakly colored by
other wavelengths. As the lure dives further down in the water column
yellow wavelengths start to disappear, then green. Blue, indigo and violet
penetrate the deepest, but even these peter out eventually.
When we start to investigate the depths at which these changes take place
things get a little more hazy (excuse the pun). Figure 3 shows the depths
to which various wavelengths of light penetrate crystal clear ocean waters
at noon on a calm summers day. It also shows how this would affect a
multi-colored lure travelling at these depths.
Figure 3: Depths to which visible wavelengths penetrate ocean
waters, and the impact that wavelength absorption has on lures trolled at
various depths.
In other words, if you were trolling a red lure at a depth of 15 meters in
the open ocean it would appear to a fish at that depth to be a dark color.
At first glance this doesn't seem like a big deal. After all, most lures
won't get to anywhere near those depths without the use of paravanes, lead
core lines or downriggers.
Ponder on it a bit longer and you'll see just how significant these
figures are! If you refer to what I said about the above figure there were
2 qualifiers in my statement. First, the figure refers to crystal clear
ocean water and second it refers to the time of day and year - noon in
summer. The figure above gives the absolute best-case scenario, but in the
real world this doesn't really help angler because we mostly don't fish
crystal clear ocean waters and we often don't fish at noon in summer (for
many species that's the WORST time to fish). That means the color of our
lures appear to be different to the fish depending on the time of day we
fish and the waters we fish in.
Water clarity and color
In deep ocean waters there are a couple of prime reasons why light
penetrates so well - clarity and color.
Clarity (the opposite of turbidity) refers to the lack of suspended or
particulate material such as silt, algal cells and similar in the water.
These particles have the effect of causing light to scatter, being
reflected off in all directions, reducing the penetration of all
wavelengths, but especially the longer ones (like red). In open oceans the
water is generally (but not always) very clear, hence light penetrates to
far greater depths than near shore or inland waters. In these waters
things like pollution, erosion, algal growth and the like cause a
reduction in clarity, with significant reductions in the penetration of
light. These reductions in light penetration begin to happen even before
the turbidity becomes visible to the naked eye (Figure 4).
Figure 4: Visible wavelengths are absorbed more rapidly and the
perceived color of lures occurs at shallower depths if the water is not
clear.
Color (of water, not lures) refers to a characteristic caused by dissolved
materials, especially organic acids from decaying terrestrial or aquatic
vegetation. A good analogy is a cup of tea - it has good clarity, but is
strongly colored. Color reduces light penetration by absorbing some
wavelengths more than others. Interestingly it's the blues and greens that
are most affected (Figure 5). Where I live there are lakes and rivers that
are so highly colored by natural organic acids that the blue/green
wavelengths won't penetrate more than a centimetre or two (1/2 to 1"). Yet
the water in these lakes is as clear and pure as anywhere in the face of
the planet and many of them are as close to pristine as you can get, save
a few trophy brown trout (an introduced species here).
Figure 5: Water that is colored by organic material absorbs the
blue wavelengths more readily, causing blues and purples to disappear from
sight.
Seasonal cycles
To make matters even more complicated, seasonal cycles in water color and
turbidity also occur in many lakes and a number of different cycles are
possible. Figure 6 shows the cycle in a lake that suffers nutrient
pollution that results in significant algal blooms. Light penetration is
reduced in summer by increasing concentrations of algae, with the red,
orange and yellow most severely affected. Algal blooms peak in autumn,
with significant reduction in the penetration of all wavelengths, but
especially red, orange and yellow. In winter the algae die off and the
water clears. Light penetration is actually better in winter, despite the
lower intensity and the reduced angle of the sun. In spring there is an
influx of silt from floods, causing a reduction in the penetration of all
wavelengths, but especially the blue ones.
Figure 6: A seasonal cycle in turbidity affects light penetration
and means that the depth at which colors become less visible is constantly
changing.
Time of day/year
I know it seems unlikely that your lure could appear to be a different
color depending on the time of day or the month of the year, but it's a
reality. To put the idea into a terrestrial context, think about how we
see color on a clear day in the afternoon compared with a cloudy day at
dusk. On a clear day with the sun overhead there are fewer gas molecules
and airborne particles to scatter the short (blue) wavelengths, so the sky
appears blue. Towards dusk the light travels through a lot more gas and
airborne particles, so lots of the blue wavelengths get scattered and
don't reach our eyes. Red and orange wavelengths eventually give way to
indigos and violets as the sun sets. The many changing hues of the sky
also change the color of other objects we see in the colored light.
The aquatic environment not only emulates what happens above the
waterline, but magnifies the effect. So the loss of blue wavelengths at
each end of the day is much greater underwater and starts earlier in the
day than it does above water. Remember that these are the ones that
penetrate deepest, so the period over which colors are visible deep in the
water are much shorter than they are at the surface.
Figure 7: The angle at which light strikes the water surface alters the
depth to which colors are visible.
Figure 7 shows how light penetration is affected by the angle of
the sun above the water. Note that all the wavelengths penetrate the water
to the same extent, but as the light comes in at an angle it doesn't reach
the same depth.
In a similar way the sun is more directly overhead so fewer of the short
wavelengths get scattered and on land we tend to get brighter and more
intense light (and the really short wavelengths get through, hence we get
sunburnt!). In winter we get more subdued light, partly because the light
travels a greater distance through the atmosphere and partly because
clouds add water molecules to the atmosphere to further filter out light.
This means that many wavelengths don't penetrate as deeply into the water
during winter, so a lure travelling at a depth of 5m in winter could
appear to be a different color than in summer, all other things being
equal. This effect is much more pronounced the further you travel from the
equator.
Other influences
Any ripple on the surface of a water body has the effect of increasing
light scatter and hence reduces light penetration into the water.
Pollution, both air and water, can also influence light penetration and
hence the color that lures appear underwater.
Putting it all together - Tips for lure color selection
So now we get to where this article has been leading - choosing lure color
for maximum benefit. When you start combining the effect of all of the
above influences you can see that it is most unlikely that we'll be
fishing under conditions that are perfect for light penetration into the
water. More often than not, some or all of the above factors will come
into play and will alter how the fish see lure color. So how do we choose
the best lure color for a particular set of conditions?
Well, here are a few tips to consider:
1. Use dark colors at night. This may seem strange to the novice,
but from experience it definitely works. When you think about it, all
colors appear to us at night to be black or shades of dark grey. Usually
when we see something at night it's a shadow, and dark colors give the
best shadow. Also, fish usually attack lures from below at night and
during low light conditions. This is because it maximises the benefit of
any limited light available. Under these conditions a dark lure throws the
best silhouette and is therefore the most visible. Black, dark blue and
purple are good choices at this time of day.
2. During winter or periods when there is lots of particulate
material in the water (such as silt or algae), reds and oranges are the
first colors to be filtered out. Under these conditions, lures with plenty
of yellow, green or blue appear the most colorful below the surface.
Fluorescent yellow and greens are also worth a shot.
3. Red, orange, yellow, silver and metallic colors are most intense
during bright summer days in clear, shallow water. Having said that,
metallic finishes have some benefits at depth because they have a tendency
to create flash, even under relatively low light conditions. Mind you, all
colors are visible under these bright conditions and if the fish are
actively feeding on baitfish that are blue in color, then that's the color
to use.
4. Color choice is a moot point if you are deep trolling using a
downrigger or paravane, particularly under low light conditions or if the
water is colored or dirty. The most important factors under these
conditions are lure size, shape and action.
5. When fishing topwater lures, color is far less important than
size, shape and action. A fish coming up below a surface or shallow
running lure has the light behind it, making the lure appear grey or
black. Try it for yourself - hold a fluorescent lure up to the sun and
view it from below. Black and dark colors remain the best for surface
lures because they throw a great silhouette.
6. Red and orange lures come into their own in tannin stained
waters, as do fluorescent hues.
My strategy
Like I said, these comments are likely to upset a few hardened anglers who
are certain beyond doubt that their fluorescent orange lure is the best
color to troll for trout at a depth of 30 metres during winter in their
home lake. The reality is often that the size, shape, action or noise made
by the lure play a much more important role in eliciting a strike. Don't
underestimate angler confidence either - we will tend to persevere more
and try harder with a lure we have had success with in the past.
My philosophy on lure selection is simple: choose a lure based on the size
of local baitfish, the depth at which your quarry is to be found and the
action most likely to produce results. Only then think about color, and
don't get too hung up on the subject. The exception: fishing in clear,
shallow water, especially if the fish are feeding predominantly on
baitfish of a particular color.
As I said at the beginning, too often a lure will be selected on color,
when the chosen color is often not visible to fish anyway.
Oh, and by the way, I have deliberately overlooked a key topic here - the
use of color combinations, patterns and contrast to increase hook-up
rates. This will be the focus of a future article!
About the author:
Dr Greg Vinall is a professional limnologist (aquatic scientist). His
company, 'The Luresmith', is dedicated to helping anglers make and use
their own lures.
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