The immense size of a manta ray, with a wingspan that can reach up to 23 feet, makes it one of the most recognizable animals in the ocean. This gentle giant is often characterized by a simple palette of black and white, a coloration that appears straightforward but is actually a complex, functional system. The true answer to what color a manta ray is depends not only on its species but also on the biological purpose of its skin pigmentation.
The Standard Coloration: Countershading and Camouflage
The typical manta ray exhibits a color pattern known as countershading, a common form of camouflage across the animal kingdom. This pattern features a dark dorsal, or upper, side and a pale ventral, or underside, which serves to conceal the ray from both predators and prey. The design is a direct response to the way sunlight penetrates the water column.
When a potential predator, such as a large shark, looks down on the manta ray from above, the ray’s dark back blends with the shadowy, deep waters below. Conversely, when a predator or prey looks up at the ray from below, the pale underside mimics the bright, sunlit surface of the ocean. This contrast effectively flattens the ray’s three-dimensional shape, making its outline indistinct and difficult to detect in the open water.
Countershading is an optical strategy that minimizes the animal’s silhouette and contrast against the background light. The dark-on-top, light-on-bottom coloration works to neutralize these effects, allowing the manta ray to move through the water with enhanced concealment.
Distinguishing Species by Color and Pattern
Although the general countershading pattern is shared, the two recognized species—the Giant Oceanic Manta Ray (Mobula birostris) and the Reef Manta Ray (Mobula alfredi)—are differentiated by the finer details of their markings. These subtle variations in color and pattern act as specific identification markers for researchers. Species are reliably distinguished by examining the distinct markings on their dorsal surface and the unique spot arrangements on their pale ventral side.
The Reef Manta Ray prefers coastal habitats and coral reefs. It has white patches on its dark dorsal surface that form a distinct black “Y” shape. Its ventral side is typically covered in a pattern of dark spots that extend across the entire abdomen and wing edges, often accompanied by a black border along the lower body. The area around the mouth, including the cephalic fins, is usually a paler color.
The Giant Oceanic Manta Ray roams the open ocean and displays a different arrangement of markings. The white patches on its dorsal side form a black “T” shape, a key distinction from its reef-dwelling cousin. On the ventral side, the dark spots are concentrated mainly between the gill slits and the tail, and do not typically spread across the pectoral fins. This species often exhibits a prominent black border along the edge of its underside and generally has a black mouth color.
Rare Color Variations
Beyond the standard black and white, rare genetic mutations can result in striking color variations, creating unique individuals highly sought after by researchers. One variation is melanism, a genetic condition caused by an overproduction of the dark pigment melanin, resulting in individuals that are almost entirely black on both their dorsal and ventral sides. Melanistic manta rays, or “black morphs,” are the most prolific example of all-black marine species, though their frequency varies significantly between geographical populations.
The opposite is leucism, a rare mutation that results in the partial loss of all pigmentation, leading to an exceptionally pale or pure white appearance. Leucistic individuals are not true albinos, but display a white or cream coloration due to a genetic inability to deposit pigment in the skin cells. In one unusual case, a male reef manta ray was observed with erythrism, a condition causing an abnormal redness that gave its underside a distinct pink hue.