By Kent Coules, Publisher
One of the most popular activities on the Big Island of Hawaii is nighttime swimming with giant manta rays. These giant “birds of the ocean” can awe the most experienced scuba diver and strike fear in the more cautious novice. If you’re thinking about viewing these amazing creatures up close in their feeding habitat, here’s five fascinating things you’ll want to know before sliding off the side of a boat:
1. By giant, we mean giant.
Giant manta rays have wingspans that can reach as large as 25 feet and the largest can weigh as much as 3,000 pounds! A common size is a wingspan of approximately 15-feet.
Newborn manta rays have wingspans of approximately six feet! How is that possible? Because they come out of the mother’s birth canal resembling “rolled burritos.”
2. If you need to cheat on a test, sit next to a manta ray.
Dolphins are known for their intelligence, so it might surprise you to learn that manta rays have the largest brains of any fish. And the size of their brains apparently translates to high intelligence. Rays are one of the only fish species on earth to demonstrate self-awareness via a mirror test.
Giant manta rays have been filmed checking out their reflections in a way that suggests they are self-aware. Only a small number of animals, like great apes and bottlenose dolphins, have passed the mirror test.
Csilla Ari, of the University of South Florida in Tampa, filmed two giant manta rays in a tank, with and without a mirror inside. The fish changed their behavior in a way that suggested that they recognized the reflections as themselves as opposed to another manta ray. The rays also blew bubbles in front of the mirror, behavior that Ari had not observed in the rays before
3. Some giant manta rays qualify for an AARP discount.
Giant mantas have an estimated life expectancy of 40 years, and it is believed that some can live as long as 50. Research is limited so the numbers aren’t universally accepted but these are the best scientific estimates at present.
4. Take their prints.
The spots and blotches on the underbellies of giant manta rays are equivalent to human fingerprints. No two bellies are alike, allowing researchers to track manta rays and identify them from year to year.
5. The question everyone wants to know: are giant manta rays safe to be around?
Manta rays are gentle giants. Like many other mammoth fish in the sea, they are filter feeders that eat the smallest of prey. Unlike stingrays, manta rays don’t have a stinger, so divers have nothing to fear.
Among the ocean’s other species of cartilaginous fish such as sharks, manta rays show to be a little more tolerant to human presence. Some divers mention that these giant fish swim around them in a slow and graceful shape, and wonder whether they are observing or being observed.
Checking “swim with giant manta rays” off your bucket list