Photo: Xerantheum @ Wikipedia
Growing up I remember being entertained on my outings to the beach by Bull Kelp. Dragging the long whips along the beach and puncturing the bulbs to hear the sound of the gas escaping.
Until recently I have never thought of the functionality of this whip like algae that wash ashore. After traveling back from Sucia Island and observing the large “islands” of floating kelp, I wondered the function these odd looking marine plants to the surrounding ecosystem.
Nereocystis luetkeana (Bull Kelp) is anchored to a rocky substrate by a root like structure and attaches to a long stipe, leading to round fist where leafs protrude. It grows like weeds along the Pacific Coast, sometimes up to ten inches in one day and provided crucial harbor for invertebrates and juvenile pelagics (Monterey Bay Aquarium & Whatcom County). They also function as gathering places for birds and otters as a place to scavenge for food. Their placement along the coasts can protect the coastline from breaking waves that erode the shore. When they die in the fall and winter, Bull Kelp provide nutrients to the surface and shore where they land, which can aid when primary production is low (Springer, Hays & Carr 2006). They have a crucial holding in the maintenance of an ecosystem.
Detrimental actions like storms and boating can uproot forest or remove the tops of the kelp (Springer, Hays & Carr 2006). Typically reproduction happens on a small geographic scale, so any damage to a local population could remove a forest.
Fun fact that I learned about the gas that is contained in the thick leathery material was that the 10 percent is carbon monoxide, which seems fairly concentrated, but not enough to do much damage to my developing brain popping the bulbs all over the beach.
References
Monterey Bay Aquarium (2010). Bull Kelp: On Exhibit. Retrieved 10/3/10 http://www.montereybayaquarium.org/animals/AnimalDetails.aspx?id=779433
Whatcom County Marine Resources Committee (March 2005). Marine Life In Whatcom County: Vegetation Series: Bull Kelp. Retrieved 10/3/10<http://whatcom-mrc.wsu.edu/Fact_Sheets/Bull_kelp.pdf>
Springer, Y., Hays, C., Carr, M. (October 2006). Ecology and Management of the Bull Kelp, Nereocystis luetkeana: A Synthesis with Recommendations for Future Research.