Friday, August 15, 2014

Manta Rays on the Alabama Gulf Coast

The manta ray is the largest species of stingray. The largest specimen documented was over twenty-five feet wide and weighed an incredible five thousand and one hundred pounds. The typical manta on the Alabama Gulf Coast tops out at 15 feet wide and 500 pounds-- still a huge fish!

It has been speculated that manta rays evolved from smaller bottom feeders, possibly the sting rays that are common on the Alabama Gulf Coast. Eventually, they adapted and became filter feeders. Their rectangular mouth is perfect for open-ocean feeding. Plankton and fish larva are the main source of food for the manta ray. Mantas are a food source for small fish-- the smaller fish gain nutrition by cleaning parasites from the manta.

Mantas are prey for sharks and orcas, even though mantas are closely related to those creatures.

A Manta Ray Glides under the Surface of the Ocean

Mantas are usually dark in color and can be brown, blue or black on the top. The edges are lighter and they have a white underbelly. They do have some patterns on their skin. Researchers and scientists use these patterns to identify individuals.

The teeth of the manta have changed over time. The teeth in the lower jaw are now covered by skin. The dermal denticles (similar to fish scales) have also been reduced in size and number. Mantas have a tail that is similar to that of a stingray; however, they do not have stingers in their tails. They are not dangerous to people in the water.

Mantas are really curious creatures, and they often swim close to humans. Mantas will occasionally come close to the surface and swim near boats just to check out what is going on up there. They are actually very funny to watch as they really try to interact with people, in a good way.

It is important to never intentionally touch a manta. Touching the ray will remove the mucous layer which protects the skin. Merely touching the manta ray can cause lesions that will take months to heal. This is dangerous to the fish because bacteria can enter the wound and cause a major infection that could result in death.

There is a new program that allows scientists to tag any manta found offshore in coastal Alabama. These tags are the same as global positioning sensors. The researchers can monitor the patterns of migration of the rays. This will allow them to understand where they travel and for what reasons. Understanding their migratory patterns can help scientists learn more about the elusive manta.

It is really important for anyone that sees a manta in coastal Alabama to contact the Dauphin Island Sea Lab. The lab is trying to keep track of the mantas that come into the area