Prudhoe Bay Kelp Beds

October 29, 2006
By Damond Benningfield
Episode:

Prudhoe Bay is home to one of the richest oil reserves in North America. It’s also home to another natural resource -- the only large kelp bed along Alaska’s north Arctic coast in the Beaufort Sea. Federal regulations try to make sure that the two can coexist.

Prudhoe Bay kelp bed. Photo: Ken Dunton

The kelp grows atop an area of rocks and pebbles deposited by a glacier along the coast. The sea is deep enough that the kelp don’t freeze during the winter, and clear enough that they get sunlight during the summer. The kelp beds are home to many aquatic animals, including corals, sponges, and mollusks.

Scientists discovered the kelp beds about 30 years ago, and they’ve been studying them ever since. They’ve found that the growth pattern is different from most seaweeds because they have a two-step growing cycle.

During the brief summer, when sunlight reaches them, the kelp store carbon -- one of the essential ingredients for growth. They don’t actually grow much, though, because there aren’t enough nutrients.

They grow during the winter, when ice covers the surface and the seafloor goes dark. Decaying plant and animal matter release nutrients. The kelp take up the nutrients, use their stored carbon for energy, and grow and reproduce. A good 90 percent of their leafy growth takes place during winter.

Federal regulations prevent development atop these unique kelp beds. But drilling and other oil activities in the area can stir up sediments, making the water murky and depriving the kelp of sunlight. Scientists are watching the kelp beds to see how they survive.

This program was made possible by the National Science Foundation and the Minerals Management Service.

copyright 2006, The University of Texas Marine Science Institute