Star Thrower Educational Multimedia (S.T.E.M.) Dive Dry Column

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Dive Dry with Dr. Bill

099: Blind as a Bat... Ray

I'm occasionally asked by divers and non-divers how I can dive the Casino Point Dive Park so frequently and not get bored. Bored? Are you kidding? One of the things I love about diving (or hiking Catalina's hills) is that if you keep your eyes open, you will almost always see something new... a species, a behavior, an interaction. I go listen to karaoke at El Galleon on weekends for the same reason... you never know what to expect! Sometimes the singers are fantastic, others times... well, they sound like me.

A recent dive offered verification of this. Over the past month or so, I've noticed a bat ray in the park that appears to be vision impaired. I can't really say it is blind as a bat... ray. It does appear to have some ability to see, but even less perfectly than me without my glasses underwater. I've been filming quite a bit in a favorite passageway or channel between the rocky shore and the inner edge of the kelp forest. It is an area with a number of garibaldi nests and cleaning stations. Black sea bass also seem to use this channel occasionally.

Several times while filming I've looked up to see a bat ray heading straight for me. Some sort of sixth sense caused me to raise my head. The strange thing is that the bat ray keeps coming towards my head until it gets very close, then abruptly does a 180 and leaves. Since I'm a big guy, with lots of bubbles emanating from my regulator, I'm fairly easy to detect even underwater. Most bat rays sense my presence at distances of 20-30 feet. This one doesn't detect me until it is just a few feet away.

On top of this, when it finally undertakes its evasive action, it often is very awkward. Several times it has run right into thick kelp it could not penetrate. Once I even watched it flee and swim right into a large rocky reef. From these scientific observations, I must deduce that this individual needs contact lenses (glasses would be quite awkward underwater). When bat rays bottom feed, the sandy sediments are stirred up so much that vision probably isn't necessary to eat. This individual does not appear to be malnourished.

On the day in question, I was again in the channel and saw the bat ray heading directly at me. Again it veered off suddenly when it got close. I thought that was the last I'd see of it. However, a few minutes later I encountered it again. I was able to catch up easily as it slowly glided through the shallows of the kelp forest. I positioned myself right behind it with the camera rolling. I swam that way for several minutes and did not elicit any response from the ray. At times I was within inches of its body, even the head region. It appeared to be totally unaware of my presence.

What followed was one of the most memorable dives I have ever had. I swam with this graceful and beautiful relative of the sharks for nearly 15 minutes. It wove in and out of the kelp (although not always gracefully), with me swimming just above and behind it. With my eye glued to the tiny viewfinder, I relied on the bat ray to guide me through the waters. In retrospect it seems crazy to let the blind lead the blind, yet it worked flawlessly. It was one of those absolutely incredible, transcendental moments one can experience when one is Zen-like and in the moment (a state of mind diving often brings about in me).

Towards the end of this encounter, the bat ray glided down to the bottom. As it landed, it bumped into a small rock outcropping. I wanted to get some good close-ups from the front, but as I moved into position it seemed to detect my presence (probably as a shadow) and took off. Looking at the video afterwards, the bat ray appeared to have one eye missing and the other one possibly glazed. It was the "good" eye facing me on the bottom.

I did follow the ray for another minute or so until I realized I was almost out of air (OOA). Although I had my pony bottle as a backup, I was able to do my safety stop and reached the surface just as the tank ran out. I have had a chance to show the footage to several people. One called it "awesome," a visiting Harvard student thought it was "mesmering," and another said it was some of the best footage I've ever shot. I hope to get it on our local cable soon so I can share this incredible experience with all of you. Who says a thousand dives in the Dive Park have to become boring? And the same goes for life topside!

Images from the close encounter with the "blind" bat ray.