Each day, as the tide ebbs lower and lower, an amazing algal forest emerges. Kachemak Bay is home to a plethora of intertidal plants and animals, representing hundreds of species. Identifying and classifying all the unique coastal habitats and intertidal communities of Kachemak Bay can be quite a challenge for researchers.

Scientists around the world face this same dilemma: how to quantify the biodiversity of an area and establish a baseline understanding of what our world's coastlines harbor. Scientists studying the consequences of the Exxon-Valdez oil spill could have used just such a baseline dataset.

In 2002 researchers in Japan developed the NaGISA (Natural Geography In Shore Areas) project, an international effort to quantify nearshore biodiversity. They focused on rocky intertidal and seagrass communities, which are found from Pole to Pole.

The first NaGISA sampling in Kachemak Bay began six years ago at three sites near Kasitsna Bay Laboratory on the south side of the Bay. Every summer University of Alaska Fairbanks students resample these locations. This year, students are assessing how these long-term, rocky intertidal communities may be changing on a small time scale, and, by sampling new sites in new areas, learning how these communities vary throughout the Bay

Waking up as early as the low tide dictates, student research crews gather supplies together, don waders, hop into the skiff, and speed off to one of the study sites. They drape tape measures across the rocks in the high, mid, and low zones and begin sampling. A percentage of area covered by individual algae and invertebrate species is estimated and animals are counted in five intertidal areas, of nine square feet each. It is like a constant game of hide-and-seek to peer under blades of kelp and find crabs, sea stars, and anemones hidden in this unassuming seascape. The species found and recorded will help to paint a larger picture of Kachemak Bay's diversity, and how the Bay fits into the biological puzzle of the world as a whole.

Erin Satterthwaite and Kelsey Lane, of California and South Dakota, are NOAA Hollings undergraduate research interns at the Kachemak Bay Research Reserve for the 2009 summer season.