This is my first blog foray into what for me is one of the most beautiful marine ecosystems found anywhere in the world. At work, I am affectionately known as Dr. Kelp for my passion about, and interest in, the giant kelp (Macrocystis pyrifera). Giant kelp is the largest of all algae found on Earth. Algae are not plants, and suffice it to say that is based on evolutionary reasons, the details of which I won't get into here. While not plants, they are able to use sunlight and carbon dioxide to produce new material - the same process of photosynthesis carried out by green plants.
In today's photo you see just the very end of a frond of giant kelp. Each frond is composed of the leaf-like blades, the round and buoyant floats, or pneumatocysts, at the base of each blade, and stem-like stipe to which the floats and blades are attached. Each frond attaches at the base of the algae, and each individual algae can have anywhere from 2 to 50 fronds, or more. The fronds grow at the tip, so today's photo shows the growing tip of a frond as it reaches toward the surface and sunlight.
Giant kelp grows in ocean waters that range in depth from 15 feet (4.6 meters) to 80 feet (24.4 meters). The shallow depth limits is generally set by water turbulence, and the deep depth limit is set by water clarity that limits the depth to which light sufficient to support photosynthesis can penetrate. Once fronds reach the surface, they can continue to grow, sometimes reaching lengths of 150 feet (45.7 meters). This growth habit means that giant kelp forms a surface canopy that soaks up the sunlight and enables giant kelp to attain frond growth rates approaching 2 feet (60 centimeters) a day. This rate is certainly extreme, with average rates closer to 8 to 12 inches (20 to 30 centimeters) per day. This easily rivals the growth rate of bamboo, and makes giant kelp the fastest growing photosynthetic organism on Earth.
Where the bottom is rocky, multiple giant kelp will occupy the area, forming what are called kelp forests. These marine forests are true forests in every sense of the word. Instead of trees, this forest is formed giant kelp and is occupied by at least 800 species that are almost exclusively associated with kelp forests.
Forests of giant kelp are found along the Pacific coast of North America from the middle of the Baja California Peninsula to the Aleutian Islands in Alaska. Interestingly, this is the only place in the northern hemisphere where giant kelp exists. In the southern hemisphere it is distributed around the globe, being found in South Africa, Australia, New Zealand, Chile, and many of the sub-Antarctic islands that are found between these landmasses.
This shot was taken with a Canon EOS 10D dSLR with an EF 17-40 zoom lens set at 17mm. The exposure was 1/60 sec. at f/8.0 at ISO 100. The camera and lens were housed in an Ikelite housing and lighting was provided by twin Ikelite DS-125 strobes set on eTTL.