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The Lorax for the Kelp Forest
Scuba Legend
Reaction score
Santa Catalina Island, CA
# of dives
2500 - 4999

Government agencies often use three character acronyms. You've probably heard of the FBI, CIA and NSA. I'm not a member of any of those (but I think at least one of them must have a file on me from my days as a 60s radical!). Well, biologists and others aren't immune from abbreviation addiction either. We use them on occasion ourselves when we are too lazy to spell things out. It works fine for those of us that understand the lingo but not always so well when we're trying to communicate with the public.

A few three character abbreviations that have been useful in my decades as a research scientist come to mind: GPS, GIS and MPA. Today most people understand what GPS refers to... most of us have one in our cars to navigate unfamiliar roads. Thirty plus years ago when I first started using one, not so many were familiar with it. Of course GPS refers to the global positioning system used to aid our military. Back when I first used it, accuracy was abysmal since the Defense Dept. utilized "selective availability" (SA) to degrade the signal received by civilians.

I once sat on my porch and took GPS location readings every 30 seconds for several minutes. When I plotted them, the readings were off by as much as 1/8th of a mile. I remember a mainland university professor wanted to use GPS to map features in our local dive park. I tried to explain that the accuracy of such a map would be useless. Nonetheless, two of us dove to the location of each desired feature and released an air-filled bottle on a line. The professor and her assistant then took a position reading at the surface where the bottle popped up. To no surprise, that map never appeared in any of her publications!

I did utilize GPS in my research though once SA was turned off. I'd record positions for things ranging from drifting kelp rafts to rare and endemic ironwood trees on land. It also became a tool when used in conjunction with a GIS. A Geographic Information System is a computer database that records various features and displays them based on their geographic coordinates. Initially I used such a system to study the distribution of giant kelp (Macrocystis pyrifera) beds around Catalina Island as part of my Ph.D. research. Later I used many of the same data layers as I developed a GIS for the Catalina Island Conservancy's science, ecological restoration and education programs.

For the kelp research, I carefully digitized a series of giant kelp distribution maps around Catalina dating back as far as 1934. I could then view all of these maps together and identify areas along our shoreline where kelp persisted over time. By incorporating additional data layers such as sunlight, depth, submarine slope, submarine aspect, storm exposure, etc., I could analyze what physical factors might contribute to the persistence (or absence) of kelp. My research purpose in doing this was to identify regions around the island that might be suitable for designation as marine reserves.

When the Marine Life Protection Act (MLPA) was passed in 1999, my GIS research became a valuable tool in looking at potential areas around the island to designate as MPAs (marine protected areas). In fact one of my papers (see http://www.starthrower.org/research/kelpgis/ijmargeo.htm) that I published two years earlier was listed as one of the top 10 scientific papers covering the topic of marine reserve selection. That list was chosen by other marine scientists and sent to then NOAA Administrator Dr. Jane Lubchenco.

I don't do a lot of research science today. I have a lot more fun SCUBA diving, observing critters and writing my "Dive Dry" columns about them. A relatively small number of people read scientific journal articles. On top of that, despite putting years into the research and write-ups, we don't get paid for them. I've earned a lot more writing these columns and have had a far larger audience reading them!

© 2021 Dr. Bill Bushing. For the entire archived set of nearly 900 "Dive Dry" columns, visit my website Star Thrower Educational Multimedia (S.T.E.M.) Home Page

Image caption: Hand-held GPS unit and kelp bed map from one year; kelp bed maps from four years and kelp persistence map.

DDDB 894 GPS GIS and MPA sm.jpg

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