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Day One at the Fifth Annual
California Islands Symposium
Expedition Class Materials
Monday, 3/29/99
Giant Bladder Kelp Beds, Weird Weather, and GIS Studies
on Santa Catalina
Dr. William Bushing, known as ‘Dr. Bill’ to our campers is a Trail
Guide for Camp Internet who lives and works on Santa Catalina Island. His graduate work to earn his Ph.D. was in using GIS – Geographic Information Systems – to study the kelp beds off the Southern California coast, and has been working as the Director of the Catalina Island Conservancy where he shares his research online using the valuable Conservancy web site.
Camp Internet staff attended a talk Dr. Bushing gave at the
5th Annual California Islands Symposium, March 30th, 1999. The following is a field report on Dr. Bushing’s presentation.
First, Dr. Bill let the audience know that what he studies are Giant
Bladder Kelp beds that are underwater forests teaming with life, light, and that are sensitive to changes in weather, among other factors. Catalina has a unique kelp bed to study in that it has not been commercially harvested and is relatively intact as a natural forest under the sea. He explained that there are seven marine reserves along the coast of Catalina Island, primarily created for recreational areas, and that there is a need to also create reserves to protect these fragile kelp beds. Then, he began to show us how a scientist – a geographer / marine biologist for example – creates a GIS map to help analyze patterns in nature so we can better understand the forces that are impacting on the kelp beds.
A scientist gathers many types of data that each form a layer of
information to study. Each of these data layers first forms a separate map that creates a visualization of the data. For example, one map is the topography of the coastal waters – the shape and depth of the sea floor near the shore where the kelp grows. Another map shows the storms and wave heights that hit the same coastal areas. Then another map shows the directions of the storms that hit the coasts of Catalina Island. Another map shows the temperature of the waters around Catalina – including a very weird thermal event where the water heated up to 75 degrees Fahrenheit on the leeward ( mainland channel ) side of the island. And yet another map was created that shows the persistence of the kelp – how frequently it appears in what areas.
With all of these separate maps a scientist can study individual
factors that effect the kelp – regular weather patterns that dash fierce storms against the windward coast of the Pacific ocean side of the island, and weird weather patterns that lead the waters on the leeward ( mainland channel ) side of the coast to heat up to a strangely warm 75 degree Fahrenheit. These maps each present a part of the puzzle of why the kelp beds are healthier and more long lasting in certain places, why they are more vulnerable in other places, and why they are disappearing all together in other places at an alarming rate.
GIS is a software system that then takes all of these individual data
layers = maps, and creates an overlay where all of the factors are represented on one map. Once you have all of the data layered together, it is now possible to begin seeing which forces are effecting the kelp – and to make some surprising discoveries.
For example, Dr. Bill expected that the kelp would be the healthiest,
and thickest, on the leeward side of the island, facing the California coast, where the shoreline is better protecting from the lashing Pacific storms. But this was not what the data showed in his studies. Actually, to everyone’s surprise, the kelp is healthier and thriving much more strongly, in the deeper waters of the windward side of the island, facing the open Pacific seas, even thought it has to contend with powerful Southern Chubaro storms with high wave height, and intense seasonal pounding surf.
What a scientist then does, after discovering that their original
assumptions proved false, is dig down into the data to try to determine what accounts for the difference in findings.
Dr. Bill has learned that on the windward side of the island, facing
the Pacific ocean, the churning of the waters ( turbidity ) is bringing more nutrients to the kelp beds, giving them better food to live on. So even though he found that the wave heights are higher on the windward side, the sea floor is deeper, and the storms hit harder, the kelp grows faster on the windward side in spite of being subjected to heavier storms.
Other factors Dr. Bill plans to study are the effects of light on the
kelp beds. It might be possible that the windward side receives more hours of daylight and less mountain shadow than the opposite side. And another factor he is studying is the fact that on the leeward side, where the waters are showing noticeable warming as an overall pattern since 1977 – with that weird 75 degree water in 1994 – kelp beds he used to find it near to impossible to dive through have since completely disappeared. Why have these beds, on the protected side of the island, where they are not hit with as intense waves or storms, suffering significant losses of kelp forests ?
GIS and Internet communication with fellow scientists is helping Dr.
Bushing explore the answers to these and many other kelp questions. Now we have a few questions for you to consider :
The kelp forest are secured to the ocean floor with giant root-like
hold fasts, and grow up towards the surface and light to heights of 80 feet or more. What types of creatures do you think like to live in these kelp forests ? One in particular is actually harmful to the kelp and needs natural predators to keep its population at a reasonable level to allow the kelp to thrive.
What do you think is warming up the waters on the leeward side of the
island that faces the mainland ?
Some people equate the kelp forests as a natural resource to the
wonders of the remaining redwood groves we now protect as parks. Would you
be interested in visiting a kelp forest preserve to learn about this under water forest ?
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