USGS
The first Earth, Life, and Time field trip was to The Chesapeake Beach and Jug Wetlands Sanctuary on October 2nd, 2005. Upon first looking at this “beach” it was a little more than a small stretch of sand squeezed between the Calvert Cliffs and the shallow lapping water of the Chesapeake Bay. But when observed closer, it contained the large variety of marine fossils and rock structures that are evidence of a much different environment that had previously existed. The group spread out and began searching for small dark fossils among the sand grains and seashells. I had terrible luck at finding these shark teeth and it took me several minutes of digging and sorting through what seemed like millions of shells, rocks, and sand grains. Finally I found what I was looking for, a tiny black triangular shaped fossil, a shark’s tooth. This artifact, barely a few millimeters in size, reveals the ancient environment that was once ruled by now extinct animals. A half hour later my plastic bag contained a large variety of teeth in size, shape, and age. I also collected bones of vertebrate animals and fish. We couldn’t have had better luck, it was an absolutely beautiful day and although it was early, most students were in high spirits when they discovered their own piece of history. Before we set to work Dr. Holtz explained about the changing environment of the Chesapeake Bay. We were standing on the shore, which millions of years ago was the bottom of twenty foot deep ocean. The shoreline was vastly different then extending miles inward towards central Maryland. The Cliffs are composed mostly of sedimentary rocks, sandstones and clay. In the face of the cliffs you can see years of deposition and lithification of these weathered rocks and “reading” them becomes as clear as children’s literature. In this way the earth’s geological features have revealed themselves through the constant changing of environment and climate; and the building and breaking down of rocks and minerals. The lower sediments were biochemical in nature, and contain a great variety of microscopic marine fossils. These diatoms were deposited earlier on and followed by clay and sand that layers for dozens of feet above.
We left that site and traveled to the Jug Bay Wetlands Sanctuary. This area that feeds into the Chesapeake Bay along the Patuxent River is monitored and protected. In this location we journeyed on a trail down along the slow moving waters of the marsh, through the dense forest, and out onto the flat stretches of twisting waterways that flow with the tides. We saw a large variety of wildlife, including colorful arrays of frogs, intimidating spiders, elegant birds such as the heron, and animated lizards. Our group then walked along a wooded area to search for a pair of woodpeckers. The Jug Bay Wetlands Sanctuary monitors the biological health of the streams and its inhabitants. The program also helps to preserve the wild species of birds and the surrounding breeding ground areas. They survey the fish populations and determine what influences are causing a change in quantity and also study the habitat and population of the Maryland Box Turtle. These are example of the kind of conservation work being done at the Jug Bay Wetlands Sanctuary.
I really enjoyed this field trip for Earth, Life and Time. The Chesapeake beach was extremely interesting and although nerdy, I was excited when I found actual shark’s teeth. The Jug Bay Wetlands Sanctuary was a tiresome walk but the wildlife and wetland plant life such as the arrowhead marsh plants kept my attention. Overall it was a very educational and worthwhile experience.
