Fishing Light Attractor

Fishing Light Attractor
From Wikipedia, the free encyclopedia

A Fishing light attractor is a fishing aid which
uses lights attached to structure above water
or suspended underwater to attract both fish
and members of their food chain to specific
areas in order to harvest them.

Just as fisherman seek conditions where the
chance of catching fish is optimized, so fish
seek areas where the chance of catching their
food is optimal. Most game fish seek waters that are rich in food such as smaller fish, insects
or shrimp. And, it follows, that these smaller fish, insects and shrimp congregate where their
food is most concentrated.

Scientific research shows that all of this food chain has eyes sensitive to the colors of blue
and green. This probably evolved because the water that these animals live in is blue to
greenish in color, depending upon how much and what kind of particulate matter is
suspended in the water. Pure water containing little particulate matter scatters light in the
blue-purple region of the spectrum. Human eyes see this water as blue. If water is rich in
nutrients and contains photosynthetic microorganisms and plants, the chlorophyll in their
bodies preferentially absorb red light. The remaining, unabsorbed light is transmitted and
scattered, thus giving the water a greenish appearance. If the water contains a lot of organic
material from decaying plant life or suspended sediment, it may take on a yellow-brown color.

Fish and some members of their food chain have color receptors in their eyes optimized for
the light of their “space”. Eyes that can see a single space color can detect changes in light
intensity. This is equivalent to a world in black, white and shades of gray. In this simplest level
of visual information processing, an animal can recognize that something is different in its
space – i.e., that there is food or a predator “over there”. Most animals living in a lighted
world have an additional visual resource: color vision. By definition, that requires that they
have color receptors containing at least two different visual pigments. To efficiently perform
this function in water illuminated with light, an aquatic animal would have visual pigments
sensitive to the background “space” color and one or more visual pigments offset from this
blue-green region, say, in the red or ultraviolet region of the spectrum. This imparts a clear
advantage to these animals because they can detect not only changes in light intensity but
also contrasts in color. Many fish, for example, have two color receptors, one in the blue
region of the spectra (425-490 nm) and the other in the near UV (320-380 nm). Insects and
shrimp, members of the fish food chain, have blue, green (530nm) and near UV receptors. In
fact, some aquatic animals have up to ten different classes of visual pigment in cells of their
eyes. By comparison, humans have three with maximum sensitivities in the blue (442 nm),
green (543 nm) and yellow (570 nm). It is the differential responses of these receptor cells
that enable color vision.

Since it has been know for a long time that a light attracts fish, shrimp and insects at night,
what is the best color for this light attractor? Base on visual receptors, the light should be
blue or green - the space colors of fish and members of their food chain. However, while blue
or green colored light is a desirable feature it is not essential. Even if fish or members of its
food chain have color receptors in their eyes centered at the blue or green spectrum, these
same receptors have a broad but decreased sensitivity to other colors. Therefore, if a fishing
light source is intense enough, other colors will also attract. For example, a sodium vapor
light with its characteristic yellow color will attract fish - if intense enough. A fishing light
attractor can also be white light because part of its total energy is in the blue to green region.

The perfect fishing light would have the following properties: 1) high intensity, 2) emit its light
in a color similar to the fishes space (blue or green), 3) be powered by a portable electrical
supply and 4) be submersible. The last attribute is desirable because significant amounts of
light energy from land- or boat-mounted lights are lost by reflection off the surface of the
water. For more information see Colors.