I recently had a pleasant exchange with a SCUBA enthusiast from Japan. Naoko is an avid diver and underwater photographer, and we became "friends" through Facebook due to our common interests. Although she is not a marine biologist, Naoko was able to answer several questions I had about Sargassum filicinum, the introduced kelp that has invaded our waters. In just a few short years this kelp, native to Japan and Korea, has overwhelmed our native species and now almost completely dominates leeward Catalina sites including the Casino Point dive park during the cooler winter and spring months. Of course here in our waters it is an invasive exotic... while in Japan it is part of the natural ecosystem.
Most of the information on this species comes from Japanese web sites, but I can't read the kanji, katakana or hiragana characters on them that might have answered my questions. I asked Naoko if she knew anything about it. She said in Japan it is known by the common name Shidamoku, and seems to play an important role in the marine environment there. Naoko thought that abalone there might feed on it.
Of course I explained how this invader was first seen in Long Beach in October, 2003. Most like it arrived on the hull or as spores in the bilge water of cargo or other ships coming from Asia. Then it was observed here on Catalina in April of 2006 by Drs. Kathy Ann Miller and John Engle, possibly introduced by pleasure craft visiting the island from the mainland. It was preceded in our waters by a closely related Asian species, Sargassum muticum, which arrived in southern California shortly after I did ... in 1970. At the time there was concern that this early arrival would become highly invasive here, and possibly out compete our giant kelp. That species has persisted, but has not become a serious ecological here over the last 40 years.
The Shidamoku kelp has become far more of a problem in our waters than any other Asian alga I am aware of. During the cooler, more nutrient rich months of winter and spring, this kelp overwhelms most rocky reefs on our leeward coast. It has made navigation in our Casino Point Dive Park difficult even for experienced divers like myself. The reason appears related to its reproductive mode. It is an annual species, meaning each plant lives its life out in less than a year. It is monoecious... , meaning that both male and female reproductive structures are found on the same plant. This allows it to reproduce and spread very quickly... unlike species with require two separate individuals to tango (or is it tangle?).
Of course the invasion of areas where a species is not native is often a two-way street. I have been interested in the appearance of our own kelp species in Asian waters as a result of the increased shipping between southern California ports and Japan, Korea and now China in the last 60 years. Imagine diving off Japan and encountering our own giant kelp growing in forests there as a exotic weed! I have not heard reports of this myself, but assume this must be occurring and I just need to learn Japanese... or become friends with those like Naoko who can interpret for me.
In one of our exchanges Naoko suggested something that turned the light bulb on in my brain (a very tricky task to accomplish). She said that Japanese scientists have been working to develop ways to use the often incredible productivity of kelps to produce biofuels that can reduce our almost insatiable need for petroleum. Algae including kelps would not require converting farmland suitable for human food production into ethanol fields. Various species of Sargassum including S. filicinum were being studied by Japan's scientists. Of course Japan has few if any petroleum reserves, so its government is not as influenced by a domestic (or foreign) oil lobby like ours is.
Perfect! Since this is an exotic species in our waters, and a highly prolific one at that, why not harvest the noxious invader and convert it into biofuel? I might even use it to power my golf cart, the infamous Dr. Bill Mobile! Not only could I save on fuel costs, if I developed some business sense maybe I could finally make my fortune by marketing this product in SoCal. Dare I say it, I could become the John Paul Getty of algal oil! I might even be able to afford all those international dive trips I had planned before the US economy tanked. Maybe I could even head to Japan and dive its waters! Anyone out there want to buy stock in my new company, Dr. Bill's Algal Oil Biofuels (DBAOB)?
Coincidentally I've been e-mailing with a former Toyon student who has an interest in converting algae into biofuels himself. Don advised me that the species chosen has to have a fairly high oil content to be useful in creating fuel. Of course that makes sense since it is the oil stored in the kelp that is converted into a petroleum substitute. Some species of algae have fat contents of 45%, but even some with levels as low as 15% have been considered. Pardon me... time to get busy researching this new idea. I'll never get rich writing this column or selling my DVDs... believe me! And on top of amassing a fortune, I may even save the world from the strangle hold of OPEC and Exxon-Mobile... all by turning vinegar into wine... er, an exotic marine weed into fuel!
© 2009 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 and on Charter Communications Cable channel 33 at 7:30 PM on Tuesdays in the Riverside/Norco area. 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!
Immature Shidamoku kelp covering a boulder at the Empire Landing Quarry and details of the immature plants;
younger plants crowding our native algae in our waters, and a dense stand of mature Shidamoku.
This document maintained by
Dr. Bill Bushing.
Material and images © 2008 Star Thrower Educational Multimedia