The question of what color attracts a shark is often driven by a misunderstanding of how these creatures sense their environment. Sharks possess highly developed senses of smell, hearing, and electroreception that often supersede their eyesight for detecting prey at a distance. Vision is only one component of their complex sensory package. Therefore, the risk associated with a particular color is not about the hue itself, but rather how that color interacts with the water column and the shark’s visual anatomy.
How Sharks Perceive Color
The biological structure of a shark’s eye suggests that most species have limited or no capacity for true color vision. The retina contains rods, which detect light and dark, and cones, which are responsible for color discrimination. A study of 17 shark species found that all possessed rods, allowing for excellent low-light vision enhanced by a reflective layer called the tapetum lucidum.
However, ten of the species examined lacked cone cells, and the remaining seven had only a single type of cone. Since color perception requires at least two types of cones, this anatomy suggests many sharks are monochromatic (seeing only in shades of gray) or have very limited color vision. The ability to distinguish between light and dark, or contrast, is far more important than discerning a specific color.
The Importance of Contrast and Movement
Sharks rely heavily on contrast to identify objects against the blue-green backdrop of the ocean. An object that creates a sharp silhouette is far more noticeable than a brightly colored one that blends in. For a shark looking up, a dark shape silhouetted against the bright sunlight is a clear visual cue.
Movement further amplifies this visual signal, especially if it is erratic or splashing, which mimics an injured creature. The shark’s lateral line system detects pressure changes and vibrations in the water. An object that contrasts visually and simultaneously creates strong pressure waves is more likely to trigger a predatory investigation.
Colors That Mimic Prey or Distress Signals
Colors commonly associated with attracting sharks, such as bright yellow, orange, and red, do so primarily by creating high contrast, not because the shark is drawn to the specific shade. Yellow, for example, stands out vividly against the blue water, earning it the nickname “yum-yum yellow.” This extreme visibility makes it an easily detectable target, especially in murky conditions.
Red light is rapidly absorbed by water, disappearing entirely beyond a depth of about 15 to 20 feet. When a red object is viewed at this depth, it loses its hue and appears dark, gray, or black. This transformation results in a dark silhouette that provides maximum contrast against the lighter water. This effect mimics the appearance of blood or the dark outline of a potential food source.
Recommended Low-Visibility Gear
The principle of low-contrast camouflage provides the most practical advice for minimizing unwanted attention in the water. Gear and apparel should be chosen to blend into the marine environment rather than stand out. Colors like muted blues, greens, and grays are recommended because they merge with the water column, significantly reducing visual contrast.
Avoid wearing items with high-contrast patterns, such as bold stripes or checkerboard designs, which can resemble prey. Highly reflective or shiny objects, including jewelry, watches, or metallic fabrics, should also be removed. These items create sudden, bright glints that mimic the flash of a fish scale, acting as a strong visual attractor.