Tag Archives: Bull kelp

Getting little respect, kelp could be the key to survival for some fish

It is all too easy for us to forget about Puget Sound’s productive kelp forests, which have been slowly vanishing from numerous places where masses of vegetation once proliferated.

I never fully appreciated the value of kelp until I began writing about the complexity of the Puget Sound ecosystem. While scuba diving years ago, I came to understand that kelp harbored a vast variety of fish, crabs and other creatures. Still, mostly out of fear of becoming entangled in kelp, I never ventured into the middle of a kelp forest. The stories I heard about divers becoming entangled are real, but they may have been overblown. (Read the story by diver/writer Eric Douglas.)

I will never know what I might have seen as a diver in the middle of a dense kelp forest, but I have always understood that kelp was generally a good thing. As a boater, however, I tended to think of the floating kelp balls and blades as a nuisance to get around or through.

Now I realize that our vanishing bull kelp has been vastly undervalued. Knowing that kelp continues to disappear leaves me with a nagging feeling of despair. I cannot conceive of the ecological loss of a single kelp bed, let alone the dozens of kelp forests that have vanished from Puget Sound.

This sense of loss reminds me of the feeling I get sometimes while driving past Arby’s in East Bremerton. I recall the beautiful stand of trees that survived next door to the restaurant through all kinds of commercial strip development. It was a rare refuge for birds and small wildlife. One day those large trees were all gone, cut down for their dollar value — out of sight but hard to forget.

I am encouraged by the serious kelp-recovery efforts undertaken by the Puget Sound Restoration Fund, led by Betsy Peabody and her staff of brilliant and dedicated ecologists. Their goal is to find ways to restart the growth of kelp in suitable areas.

I recently wrote about the work of PSRF’s Brian Allen for the Encyclopedia of Puget Sound, after he spoke at the Salish Sea Ecosystem Conference in Seattle. Inspired by the hope of kelp recovery, Brian has been developing techniques to get the kelp to grow and self-propagate without supervision.

For about eight years, Brian has been observing a shrinking kelp bed just outside Bainbridge Island’s Eagle Harbor. “It has been in steady decline,” he told me, “and for the last couple of years there is nothing showing on the surface.”

Because kelp is so important to Puget Sound’s threatened and endangered species, the work of restoring kelp forests is considered critical. That’s especially true for rockfish, some of which are listed as threatened under the Endangered Species Act.

Although it hasn’t been formally proposed, I would suggest that authorities consider finding new places for kelp to grow, perhaps by adding rocks upon which the kelp can attach. These would be not be places already occupied by eelgrass or other vegetation that helps to build a healthy food web.

Studies have shown that kelp can help offset the effects of ocean acidification, at least locally around the kelp beds themselves. While taking up carbon dioxide, they produce oxygen and help to relieve conditions that dissolve the shells of key species. Check out the story by Phuong Le of The Associated Press, who wrote about the PSRF’s work, and see the second video on this page.

While kelp’s benefits as a primary producer have been discussed through the years, researchers at the University of California – Santa Barbara recently concluded that the structure of giant kelp could be even more important. Kelp helps to slow water currents and provides shady habitat on the bottom. See the paper in Proceedings of the Royal Society along with a report by Julie Cohen of UCSB.

The causes of kelp forest decline in Puget Sound are not well understood, but the good news is that overall abundance of kelp in the Strait of Juan de Fuca and along the Washington Coast has been fairly stable since they were first mapped in the early 1900s.

The story of those early kelp surveys is pretty interesting. Kelp was considered a potential source of potash, used for fertilizer and even gunpowder. At the time, German mines were a major source of potash, but U.S. officials realized they needed another source, given a growing German belligerence before World Way I. A 1915 report by Frank Cameron for the U.S. Department of Agriculture is available online.

Check out last year’s story by Matt Wood of the University of Chicago, where the survey maps are archived. A study comparing the extent of kelp beds from the early 1900s to today was conducted by UC professor Catherine Pfister along with Helen Berry of the Washington Department of Natural Resources and Tom Mumford, formerly with the DNR.