Our goal is to collect jellyfish to compare their biodiversity on Randalls Island in two different sites: the Little Hell Gate Salt Marsh and the Harlem River. With the collected jellyfish, we will isolate their DNA, amplify the DNA using PCR, and then analyze the DNA using gel electrophoresis. We will also test the water in those sites from five different aspects: dissolved oxygen, nitrate, phosphate, pH, and turbidity. We hope to see the correlation between the biodiversity of jellyfish on Randalls Island and the collected water data.