Dive Dry with Dr. Bill

#227: Take a Lick of... Kelp, or Ice Cream!

Recently my mind drifted back to the days of my youth in the developing suburbs of Chicago. Yes, I realize that is ancient history... but they were very good times. No, I'm not that nostalgic... I could never relive them today because the woods, fields and creeks I used to roam have, as Joni Mitchell sang, been paved over to build a parking lot... or condo complex, or shopping mall. The "wilderness" of my youth is gone, and with it the snakes, snapping turtles, cottontail rabbits and other critters I used to catch and keep in my parent's garage. Back in those days I often coupled my scientific pursuits with an entrepreneurial spirit. I charged the other kids in my neighborhood a nickel to visit the "zoo" in my garage. Those were the days when a nickel bought a soda pop... or a candy bar. Gone are those days, too.

Living here on Catalina, I have no need to return to those days when "wildlife" was abundant in my own background. Living on Catalina offers all those advantages to this very day, whether one is hiking the hills to Little Harbor... or diving the waters of Emerald Bay. Given the many hours I used to entertain myself as a kid in my hometown, I have no comprehension when the kids (and some parents) on Catalina today say... "there's nothing to do here." OK, so on occasion we said the same thing about Northbrook, Illinois... yet still found many ways to entertain ourselves whether it was winter or summer. And that was in the days before TV had 500 stations, or there were video games, or one could surf the Internet for hours.

But I digress... so what's new? My thoughts drifted back to those innocent days not because of all that. It was thoughts of the simple pleasure of licking an ice cream cone with my tongue. In those days we only had three main flavors... vanilla, chocolate and strawberry. Nothing like the rainbow of varieties available at any real ice cream store today. Simple times, simple pleasures. But wait... what possible connection could there be between licking an ice cream cone and the usual subjects of this column? I'll bet you thought I'd never get there this week! Here's the connection...

A few weeks ago I was diving near Blue Cavern Point and found a mature green abalone under the lip of a rocky plateau atop a steep wall. It was upside down, at least relative to gravity. I don't think it really cared because its muscular foot was gripping the rocky substrate very firmly. I, on the other hand, was hanging from the lip of the plateau... one hand gripping the rock and the other holding my video camera and housing as I hung in mid... water! Despite this very unstable shooting position, I was trying to film the sensory tentacles along the margin of this abalone's mantle. They were "reaching" out, trying to locate things of interest in the surrounding environment. Things like a nice juicy piece of drift kelp... the equivalent to a flank steak in their feeble minds. Then it happened...

A piece of red alga was swept by the surge right in front of the abalone, and between it and my camera. At first I thought my video sequence was ruined. However, a few nanoseconds after this fragment of seaweed tantalized the abalone's tentacles, I filmed something I've never even seen before. The muscular foot of the abalone quickly reached out and tried to grab that potential meal. It missed and quickly withdrew since that soft muscle would make a tasty meal for a fish predator (or for me.. IF they were legal these days). What does this have to do with ice cream? Well, when I reviewed the video footage back at the house that night, it looked as if the abalone had extended its tongue to "lick" the seaweed just as my tongue used to do with my ice cream cone (chocolate back in those days, but now I prefer chocolate chip cookie dough or blueberry cheesecake).

I'm sure some of my readers think I'm stretching the point here, so let's take this comparison a bit deeper. When I used to consult for the Santa Catalina Island Company boat tours, one of the factoids I researched and presented to the crew was the numerous products that were made with the sodium alginates extracted from harvested giant kelp. Now almost the entire crew voted for beer as their favorite kelp-based product. However, their second place vote usually went to ice cream in which the alginate serves as an emulsifier and prevents ice crystal formation in the creamy smooth treat. Shampoo, motor oil, and other products usually ended up a distant last. So an abalone trying to "lick" a piece of kelp is not so far removed from a young child licking an ice cream cone. Ha... bet many of you thought I'd never make the connection.

Many SCUBA divers, at least the more patient among them, like to hand feed pieces of our giant seaweed to abalone IF they can find one. Unfortunately, some of our younger divers don't even know what an abalone looks like since the abalone's drastic decline some years back. Drifting giant kelp is the abalone's favorite menu item. When a diver holds a piece of this seaweed close to an abalone, it often rises up and clamps down on the alga, trapping it under its shell so it can begin munching away. My guess is that since this abalone was hanging onto the rocky lip upside-down, it didn't get many chances to catch a meal. Red algae aren't the adult snail's favorite food, but it jumped at the chance to capture this morsel as it brushed by in the surge. Although it wasn't successful in its attempt, it certainly made for an interesting video segment. Don't you agree?

© 2007 Dr. Bill Bushing. Watch the "Dive Dry with Dr. Bill" underwater videos on Catalina Cable TV channel 49, 10:00 AM and 5:00 PM weekdays. Please help me climb out of self-imposed poverty... buy my "Munching and Mating in the Macrocystis," "Great White Sharks of Guadalupe," "Calimari Concupiscence: Mating Squid, " "Playful Pinnipeds: California Sea Lions," "Belize It or Not: Western Caribbean Invertebrates, Fish and Turtles," "Gentle Giants: Giant Sea Bass" or "Common Fish and Invertebrates of the Sea of Cortez" DVD's. Yes, take Dr. Bill home with you... we'll both be glad you did!

Green abalone reaching out with its muscular foot to "lick" the piece of red alga.

This document maintained by Dr. Bill Bushing.
Material and images © 2006 Star Thrower Educational Multimedia