See the amazing giant Manta Rays off the coast of the Big Island

More than ten years ago, Hawaii enacted a law to make it illegal to hunt or kill manta rays, but no other protections. The more that we learn about Manta Rays, the more we realize how much they need and deserve protection. Manta tour operators, snorkeling and diving guides in Hawaii all follow procedures and abide by rules and regulations to protect and avoid harming mantas. Participants in manta snorkeling and diving tours are coached and guided to do likewise.

Propelled by flapping large pectoral fins, manta rays are unmistakable swimming at or near the surface or leaping or somersaulting. The largest mantas can reach as much as 3000 Ib. Their width is more than twice the length of their body. Extensions of their fins, looking like a devil’s horns, project from the front of their broad heads on either side of their mouths. Their eyes are behind these fins. Small dorsal fins are located at the base of the tail. The skin of mantas must not to be touched. It is covered with mucous that protects them from infection.

Mantas migrate to tropical waters where they feed near the surface on large quantities of plankton gathered in their mouths as they swim. Mantas also feed on fish and other organisms that inhabit much deeper waters. In Hawaii’s waters and elsewhere mating takes place at different times of the year. The courtship of mantas is difficult to observe. A male follows closely behind a female while she travels at a moderate speed. He makes repeated efforts to grasp her pectoral fin with his mouth. This may take 20 to 30 minutes. Once he has a tight grip, the mating process is consummated. Both mantas usually will continue to swim for a while.

Mantas visit cleaning stations on coral reefs for removal of external parasites. Snorkelers will see rays in a near-stationary position close to a coral surface for several minutes. Cleaner fish are consuming the manta’s parasitical organisms. In Hawaii, wrasses often provide the cleaning. Manta rays can relax during cleaning in Hawaiian waters since they are safe.

Manta rays are close relatives of sharks. Manta reproduction shares some similarities with sharks. Manta rays develop within eggs but the mother does not release them. Manta mothers gives birth to live offspring. From the egg inside the mother’s body, the baby manta is born, alive. Manta fertility is very low by comparison with other fish because females usually have only 1 or 2 offspring at a time. Manta rays deliver once about every 2-5 years and can have offspring for about 30 years.