Meeting Abstract
Michigans’s inland salt marshes are a very rare habitat in North America, and little is known about the invertebrates that live there. To gain a better understanding of the adaptations necessary to live in these habitats, we conducted two experiments. The first experiment tested a single invertebrate in two different waters, the invertebrates that were tested on were ostracods taken from the salt marsh, copepods taken from the Kalamazoo River near the Albion College campus, and Daphnia pulex that were ordered from Carolina Biological. We tested for local adaptation in the invertebrates by testing each species in freshwater from the Kalamazoo River and from the salt marsh and measuring population growth (survival and reproduction) for two weeks. We found that only the copepods had a significant difference in performance between the two environments tested. This was strange because they did better in the water from the salt marsh, which isn’t their natural habitat. The Daphnia and ostracods did not have a significant difference in survivability between the two environments. We then conducted a second experiment where each replicate contained two species of invertebrate. Both salt marsh water and freshwater were tested in this experiment. The purpose of this experiment was to test if competitiveness/fitness in these two environments gave an advantage to one of the two invertebrates being tested. In the second experiment the only invertebrate that significantly outperformed the other was the ostracod, which outcompeted the Daphnia in both environments. It was also found that there was no significant difference between the copepods and ostracods, and the copepods and Daphnia. Knowing that copepods survive and reproduce better in the salt marsh raises more questions as to why they haven’t been found there. Copepods don’t outcompete ostracods, which are naturally found in the salt marsh.
