Latest Hanauma Bay Newsletter input

Colors-part deux


In the last article I talked about how our piscine friends use color and patterns to advertise services, highlight armament, look for mates(no, not the Australian kind) and to hide in plain sight. Well, it appears that there is a lot more to it than meets the eye (pun intended)!

According to the May 2005 National Geographic, there are many additional color “tricks’ up their collective sleeves! For example, did you know that some of our critters use ultraviolet light- a spectrum where we homo sapiens sapiens are completely blind! Yup! Some fish not only see UV abut also literally paint their bodies with the stuff to beam out messages to their kin (hey Artie who was that svelte blue-finned beauty I saw you out with last night?).Some Damselfish literally shout out to each other in UV, but their predators can’t see it.

Having the ability to see in UV also helps some critters to see and acquire chow. For instance, zooplankton, one of the basic food groups in the USDA (United States Department of Aquaculture) and right up there with our catsup in the fish world food group listing appears transparent to us. Yet, many plankton eating fish don’t seem to have a problem identifying it because they can see UV light which makes the zooplankton appear black and therefore more visible in the water.

Octopus in the Bay also put color to work in many ways. They use shifting patterns of dark and light on their skin to match the color and texture of their background. They are masters of disguise!

I’ve seen them moving from rubble mound to rubble mound where they will literally stretch their body into a tent-like structure completely covering the entire mound with a web. They then probe the rubble with their serpentine arm tips to scare up potential pupus such as crabs. At the last moment, before moving on, the webbing between their legs would turn a transparent white.

The National Geographic article speculates that such a color change act is a ruse to lure small, cowering animals up to the “windows” of light and potential escape (I see the light)! In reality such action actually moves the animals closer to the octopus mouth---hmmm cleaver these octopus! Especially considering that they are color-blind!

Soo, where am I going with all this? Beats me! How bout don’t waste money on UV emitting Speedos for you’ll never know what you’re saying or getting yourself into(literally) and if you ever get ‘tented’ by a giant octopus, do not, repeat do not, swim for the light!! Much aloha, Larry Winnik