Thursday we headed to the Rancocas Cranberry Preserve, and our guides had a surprise for us. But before we arrived at the reservoir to enjoy the surprise, we learned about birding and cranberries. We saw red-winged blackbirds, wood ducks, and a circling turkey vulture who seemed have its eye on our stuck canoers. Bald eagles like the location, but we did not have the luck to see any.
Yes, we went canoeing! There were a number who were ready and willing, but some of our group challenged themselves and their fears. At one point we had seven boats on the water with a few triples. And, we only had one flip. Luckily, the lake is only three feet deep.
Julia opted not to canoe. Aquatic invertebrates were the order of the day for her: “While my classmates looked for birds and learned to canoe, I took a slightly different approach to learning about the preserve. In a pond near the main reservoir, I learned how to use a dip net to sample macroinvertebrates in the water. My findings delighted me; I caught many indicator species of excellent water quality. Despite the fact that the area used to be a farm, the ecosystem seems to have developed on its own wonderfully!! I found many dragonfly nymphs, which indicate high levels of dissolved oxygen and minimal pollution. I also found a caddisfly larvae, which are highly sensitive to pollution and eutrophication, indicating excellent water quality. There was an abundance of predacious diving beetles, which (along with dragonflies) are vital to keeping mosquito populations in check and similarly indicate high levels of oxygen. Water striders indicated that there were no heavy metals or industrial runoff present in the lake. In the bog-like area next to the lake, there were mosquitoes, water scorpions, water boatmen, and aquatic sowbugs. This makes sense given the abundance of algae and stagnant conditions (this area is not directly connected to the moving streams). These species are indicators of moderate oxygen levels and some eutrophication; however, the presence of the aquatic sowbugs, which are highly efficient detritivores, shows that the ecosystem is responding to these conditions and regulating itself—a microcosm of the greater pine barrens!“
It was a wonderful day for everyone. We had been waiting for warmth. Weather and joy gave us plenty.