When Kelp Comes Ashore
GIANT kelp is more involved in your life than you think. An article in Oceanus, by marine biologists Ron H. McPeak and Dale A. Glantz, gives information on how kelp gets from the ocean and into the lives of most of us. It is harvested along the California coast from San Diego north to Carmel.
In productive beds it may be cut three times a year. Modern harvesting vessels are pushed stern first through the beds. Reciprocating blades mounted at the base of a conveyor system operate like a seagoing lawn mower, cutting the floating fronds of the kelp canopy three feet below the surface.a The conveyor carries the cut kelp aboard. In one day a harvesting vessel can reap as much as 550 metric tons. In California the kelp industry has harvested as much as 156,000 metric tons in one year.
The kelp forest is not damaged by this harvesting. The still-submerged part of the kelp is where sexual reproduction occurs. Also, buoyancy and photosynthesis occur the entire length of the fronds. The removal of the thick canopy lets in more sunlight, which stimulates the growth of the new fronds that are beneath the surface. Soon a new canopy is formed, and another harvest is in the making.
When kelp comes ashore, it goes far beyond the coastline. Its products find their way into your kitchen, dining room, and bathroom medicine cabinet. They find their way into feed for livestock and poultry and into fertilizer for crops. Chemicals from kelp end up in the products of industry.
Kelp’s most important contribution is algin. It was first discovered by a British pharmacist in 1883. But it was not until 1929 that Kelco, a San Diego company, became the world’s first producer of algin products. Now the annual sales of these products manufactured in California exceed $35 million. Their uses are legion. “They thicken, smooth, emulsify, stabilize, gelatinize or create a film when combined with other substances.” After giving this information, Sport Diver magazine elaborates:
“Many brewers use alginates to form tougher beer bubbles, making for a longer-lasting foam head. Alginates keep cosmetic creams from separating and help maintain ice cream’s smoothness. Part of the taste and texture of chocolate milk drinks and glazed doughnuts are derived from alginates. They do everything from coating paper to improve its printing quality to making it greaseproof.
“As if those weren’t enough uses, it impregnates fabrics to help retard burning. Other forms are used in laundry starches and textile print pastes. Some pharmaceuticals contain algin, as do certain adhesives, rubber products, wallboard cements and auto polishes.”
Harvesting of the giant kelp is regulated by the California State Fish and Game Commission. May the commission do its job well to safeguard kelp from human exploitation, and may the delightful sea otters protect it from the sea urchins, that the beauty of its forests may continue to dazzle our eyes and its products continue to tickle our palates.
[Footnotes]
a 1 ft = 0.3 m.
[Picture on page 18]
Kelco harvesting vessel