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Dive Dry with Dr. Bill

#560: I Must Be Color Blind!

As my readers know, most of my dives this summer have been at night when I usually have the dive park all to myself and the action is intense. However, I do occasionally venture out in broad daylight... despite my razor-sharp fangs. A few weeks ago reports of a special fish drove me to do two long dives (85 and 78 minutes) combing the Casino breakwater from one end of the dive park to the other.

The fish I'm referring to is the Guadalupe cardinalfish (Apogon guadalupensis). It is considered rare here in the Channel Islands since we are at the northernmost part of its geographic range. I was surprised to find that fish expert extraordinaire and fellow Cousteau POS staffer, Dr. Milton Love, did not even include it in his magnificent tome Certainly More Than You Want to Know About the Fishes of the Pacific Coast. It ranges as far south as the tip of Baja and the Revillagigedos Islands, and into the Gulf of California (Sea of Cortez) as well. I have no plans to try to film them off Guadalupe Island since that is where the great whites congregate in fall, and filming from a cage will not capture these small beauties.

A dive friend posted that he had seen three of them in the dive park a while ago. At first I was skeptical since I've only seen one that I can remember in all my years of diving. However, he posted a picture and he was spot on. Since my only video dates back to the pre-HD year 2004, I wanted to get some fresh footage and did those day dives. I looked in every nook and cranny in the Casino breakwater from 10 to 29 ft and couldn't find a single one.

After I surfaced, CDS instructor Ruth Harris said she knew where one was and gave me a good description of its location. They are what we scientists call "reef associated," so they generally stay in one area. I thought finding it would be a piece of cake. However, I spent an hour looking in that small section of the dive park without a single sighting. I think I need to make an appointment with my optometrist soon. Of course I am partially red-green color blind so maybe that's why I have trouble finding them... doesn't help during Christmas either!

To the casual diver, these may look a bit like a colorful juvenile blacksmith and they are found in similar habitats... hiding deep in the small cavelets of the rocky reef down to about 100 ft. Their body shape is similar, but with a deeper belly and the head is large. I was surprised to find they may reach a length of five inches. Ruth said the one she's seen has been growing so maybe I'll be able to find it in another year or two!

Their red color makes them perfect nocturnal predators since red appears black at night... until my video lights hit home. They should be easier to spot on my night dives since they come out of their daytime shelter into open water to feed on planktonic crustaceans, other zooplankton and even small fish. However, I've done over 60 night dives this summer without spotting a single one.

Since I've only seen one in all my years of diving here, I can't say much about its love life. After all, it does take two to tango (or is it tangle?). However, they are mouthbreeders and the males carry the eggs in their mouth for protection. Once they hatch, the larvae are planktonic, allowing the youngsters to see the world before they settle down.

I did once involve this species in a human love story. My #1 dive buddy Andrea was dating Tim and he wanted to score points, but wasn't a diver. They attended one of my talks in Orange County and before I started, I told Tim that when I asked if anyone in the room could identify a certain fish, he should raise his hand and say "Guadalupe cardinalfish." Of course Andrea immediately saw through the ploy, but appreciated the effort on her boyfriend's part.

© 2013 Dr. Bill Bushing. Watch the "Dive Dry with Dr. Bill" underwater videos on Catalina Cable TV channel 29, 10:00 AM weekdays and on Charter Communications Cable channel 33 at 7:30 PM on Tuesdays in the Riverside/Norco area. You can also watch these episodes in iPod format on YouTube through my channel there (drbillbushing). Please help me climb out of self-imposed poverty... buy my DVD's (see this link). Yes, take Dr. Bill home with you... we'll both be glad you did!

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My "way-back-when" (2004) shot of a Guadalupe cardinalfish in the dive park.

This document maintained by Dr. Bill Bushing.
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