Manta rays possess one of the highest brain-to-body mass ratios among fish

The giant manta ray (Mobula birostris) is the largest ray species in the world. Its enormous, wing-shaped body can commonly reach a width of about 22 feet, while particularly large individuals have been documented with wingspans close to 30 feet.

This impressive ray is recognizable by its massive triangular pectoral fins, which extend outward and curve backward like wings. On either side of the mouth are specialized cephalic fins. These flexible structures can be extended or repositioned to help direct plankton-rich water toward the mouth as the animal feeds.

Giant manta rays are generally dark across their upper surfaces and lighter underneath. Individual animals may also have distinctive pale markings on the back or dark spots across the underside. Because these markings vary from one animal to another, they provide scientists with a useful way to identify individual manta rays.

These rays travel through the sea by smoothly moving their enormous pectoral fins in a wing-like motion. They are sometimes observed swimming in groups and are also capable of launching their entire bodies out of the water. Such breaching behavior may be connected with communication, reproduction, or play.

Classification

Order: Myliobatiformes

Family: Mobulidae

Genus: Mobula

Species: birostris

Names in Other Languages

French: Diable de mer

Dutch: Duivelsrog

Portuguese: Jamanta

Italian: Manta

Spanish: Manta Atlantica

Japanese: Oni-itomaki-ei

German: Teufelsrochen

Portuguese: Urjamanta

Importance to Humans

Historically, Mobula birostris was hunted in tropical areas of the Americas. Commercial fisheries once targeted these rays in Australian and Californian waters, primarily for their liver oil and for their skin, which was used as an abrasive material.

Deliberate hunting of manta rays is much less common today. Nevertheless, manta meat remains a valued food in certain regions, including the Philippines.

Giant manta rays have also become important to the diving tourism industry. Their tendency to gather at predictable locations and their willingness to approach divers make them highly attractive to underwater tourists.

Frequent human contact can nevertheless be harmful to these animals. Repeated touching may remove the protective mucus layer covering their skin, potentially causing skin damage and increasing their susceptibility to infections.

Danger to Humans

Giant manta rays are considered virtually harmless to people. They are not aggressive and generally present no significant danger to humans.

Conservation Status

The conservation status of the giant manta ray is assessed by the International Union for Conservation of Nature, commonly known as the IUCN.

The IUCN is an international organization involving governments, agencies, and conservation organizations that assesses the extinction risk of species and identifies conservation requirements around the world.

Geographic Distribution

Giant manta rays occur throughout tropical, subtropical, and temperate marine environments across the globe.

Their general distribution extends between approximately 35° north and 35° south latitude.

In the western Atlantic, their range includes waters from South Carolina in the United States to southern Brazil, as well as Bermuda.

Individual manta rays have occasionally been recorded considerably farther north, including sightings near New Jersey and San Diego.

Other parts of their worldwide distribution include eastern Africa, the Gulf of Aden, the Red Sea, the Arabian Sea, the Bay of Bengal, and waters throughout the Indo-Pacific region.

Habitat

The giant manta ray occupies a broad variety of marine environments, ranging from coastal waters to areas of the open ocean.

They can commonly be encountered along continental shelves, around coral reefs, near offshore islands, and in surface or mid-water areas associated with lagoons and reefs.

Their large pectoral fins propel them through the water in a characteristic wing-like movement. Although they are primarily associated with warmer seas, they may occasionally travel into cooler temperate waters.

Giant manta rays sometimes gather in relatively loose groups and spend considerable amounts of time close to the ocean surface.

They are particularly famous for breaching, during which an individual launches its entire body above the surface before falling back into the sea.

Breaching Behavior

Several forms of aerial movement have been observed in giant manta rays.

Some individuals leap forward and return to the water head first. Others move forward before landing tail first. They may also perform movements resembling somersaults.

When several manta rays are together, individuals may perform these leaps consecutively.

The precise purpose of breaching remains uncertain. Scientists have proposed that the behavior could play a role in attracting mates, communicating with other manta rays, or engaging in playful activity.

Biology

Distinctive Physical Features

Adult giant manta rays are immediately recognizable because of their enormous triangular pectoral fins and prominent cephalic fins.

The cephalic fins are specialized extensions along the front portions of the pectoral fins and are positioned on either side of the head. Each fin is roughly twice as long as its width at the base.

While swimming normally, the cephalic fins are frequently rolled into spiral-like shapes. When the ray is feeding, however, they unfold and help guide water into the mouth.

The species has smooth skin, a broad rectangular mouth positioned at the front of the head, and a tail that does not possess a venomous spine.

Unlike many other mobulid rays, the mouth of the manta ray is located directly at the front of the head rather than on its underside.

The eyes and spiracles are positioned on the sides of the head, while the gill openings are found on the underside of the animal.

When the cephalic fins are excluded from the measurement, the body disc is approximately 2.2 times wider than it is long.

The tail is somewhat flattened and is shorter than the width of the body disc.

Between the cephalic fins, the head curves slightly, producing a shallow triangular region at the front of the body.

A dorsal fin sits immediately in front of the pectoral fin axis. Its height is approximately 83% of the length of its base.

Coloration

Each giant manta ray has its own distinctive combination of markings across both the upper and lower portions of its body.

Common coloration includes dark brown, gray-blue, and black across the upper surface, often accompanied by paler edges and a white underside.

Some individuals also develop lighter markings on the back or dark patches across the belly.

Because the arrangement of these markings differs between individual animals, researchers can use them as natural identification patterns when monitoring and tracking manta rays.

Teeth

Giant manta rays differ from many predatory rays because they possess only very small teeth on the lower jaw.

There are approximately 18 rows of teeth near the middle of the lower jaw. Moving toward the corners of the mouth, the number decreases to roughly 12–14 rows.