All posts by rebeccabarulli

Creatures and Waves at the Rocky Intertidal Zone

After our first adventure on a research boat studying the Damariscotta River estuary, where we observed how the salinity and mixing state of the estuary affects the diversity of zooplankton and phytoplankton population, we moved on to Rocky Intertidal Zones. We went to Ocean Point at Linekin Neck in Boothbay Harbor, Maine. We completed a transect of the intertidal zone using our previously developed method with a 50-yard tape measure and an inclinometer to determine the slope of the shoreline. The rocky face was covered with many different forms of life, and despite the slippery surface, we found the slopes of each leg of the transect to map the estimated zones of the intertidal.


Along the transect, specifically in two-meter intervals, we took flora and fauna surveys of the sessile and motile organisms within the different quardrats we measured. We used a 0.25 m2 quadrat to measure the percent coverage of sessile organisms and a 1 m2 to measure the motile organisms. We found that the physical stresses of the exposed rock, such as the wave shock and desiccation, greatly affect what organisms can live in the exposed area. We found mostly red algae, such as Condrus crispus, right at the low tide line, and many colonies of barnacles towards the middle of the intertidal zone, where there is less exposure, but still great variation of species throughout the tide cycle. From our observations, we concluded that both physical and biological stresses greatly affect the organisms that live in the intertidal zone

After a field day of exciting research, full of wonderment and awe (as Greg would say), we enjoyed a day at the Common Ground Fair. This fair was not your typical rides and games fair, but it was very fun, and they had very good food. After the fair we went out to dinner for Greg’s birthday at Shaw’s Fish and Lobster Rolls, where the view of the harbor at sunset was beautiful. We are all as happy as clams to continue on this trip!

Acadia and Glacial Erosion

After Katahdin Iron Works, we traveled out towards the coast to Acadia National Park, where we stayed on the Schoodic Peninsula at the Schoodic Education and Research Center. Being on the shore, we were able to study the effects both of glacial erosion in the bedrock and of hundreds of meters of sea level change during and since the Pleistocene ice age. There were striations and chatter marks made by rocks embedded in the glaciers grinding across the bedrock. These allowed us to estimate the south-southeast direction of flow of the glacier. At Schoodic Point, we used the principle of cross-cutting relations to construct a relative dating history of a dozen events from granitic magma rising in the crust to basalt cooling to glacial melting to recent sea level rise and erosion.

We took a trip to Mount Desert Island, where we stopped at several places to study the glacial erosion. At Jordan Pond, we saw how the glacier moved over and around The Bubbles (two small mountains with a U-shaped valley in between), causing stoss and lee features on the up-glacier and down-glacier sides of the mountains. The stoss side had abrasion from the grinding glacier and the lee side had steep cliffs where plucking by the glaciers removed giant blocks of stone. The pond itself was formed through the repetitive retreating and advancing of the glacier. That day we also traveled to the top of Cadillac Mountain by van, where the views of Bar Harbor, as well as many of Maine’s islands could be seen.

That evening, we also ate dinner in Bar Harbor (or Bah Habah) and spent some time walking around and enjoying the sights. Because of the low tide at the time we were there, we got to walk out onto the sandbar that leads to Bar Island, which was very cool to walk across, and for skipping rocks too!

The next day, after a midterm exam (yes! a midterm!) we went swimming on Schoodic Peninsula. It was so cold! But the Bay of Fundy, where we are headed next, is going to be even colder! Its very cool to experience each aspect of what we are learning where we are, and I’m excited to find out what we’re learning about next!