Tidepools!

Last week I participated in Marine Biology camp for high school students in Bodega Bay California.  Students collected animals from the tidepools and mudflats, took them back to the lab to observe them and then designed and conducted their own experiments.  It's so fun to get the chance to approach science again from this basic level of fascination and curiosity which is what drove me to study biology in the first place.  Some of my earliest memories are of exploring the tidepools of Islesboro, Maine finding muscles, barnacles, green sea urchins, brittle stars and crabs.  I would collect shells and seaglass which seemed like mysterious gifts from an unknown world.

Rocky Intertidal habitat in Big Sur, California.  Picture by Vanessa Miller-Sims

Tidepools are special place at the interface of land and sea and the organisms that live there must deal with living in an ephemeral habitat that is constantly changing in both time and space.  The intertidal zone is defined is the area that is out of the water at low tide but completely covered at high tide. Organisms living in this environment are exposed to wave action, changes in temperature and salinity, exposure to air and sun in addition to competition for space with other organisms and predation.  The intertidal is divided into zones depending on how much of the time the organisms that live there are submerged.  Organisms that live in the highest part of the intertidal zone are submerged for the least amount of time and must have adaptations to avoid drying out while the lowest part of the intertidal is submerged most of the time and thus provides the most stable habitat.

Barnacles in Garrapata State Park in Big Sur.  Picture by Vanessa Miller-Sims

These barnacles are not covered by water and as you can see they are closed fast to keep them from drying out.  When the tide rises and they are once again covered they will open up and feed on small particles suspended in the water.

Big Sur Tidepool. Picture by Vanessa Miller-Sims

A look into a submerged tidepool shows anemones snails and coralline algae.