Last week the 5th graders had a great time participating in the Marine Science Institute’s Discovery Voyage. The students embarked on a four-hour expedition of the San Francisco Bay. During the trip the students learned about marine science through hands-on learning centers on board the R.V. Robert G. Brownlee.
At the benthic (ocean floor) ecology station, the students dredged sediment samples from the bay floor using a Peterson benthic grab-claw, then washed the mud away on screens to expose native and non-native invertebrates. Students discovered a plethora of species, from Japanese spider crabs to jellies, sponges, bay shrimp, isopods, and clams, which were put into “touch-pool” buckets for students to gently handle and study.
At the ichthyology (fish) station, students used teamwork to deploy a 16-foot net. After trawling it for several minutes, students worked again to haul the net in. Cries of ‘HEAVE-HO…HEAVE-HO” were heard yelled by students as they hauled, and much excitement followed as a leopard shark and sizable ray splashed the team that caught them. Fish were placed in buckets and students used dichotomous keys to identify them by examining their gill location, number of dorsal and pectoral fins, tail shape, coloring, eye location, etc. Additionally, adaptations for habitat and predator/prey relationships were observed, such as an intricate pattern of bio-luminescent spots on the underbelly of one fish, and the countershading of others, such as on a topsmelt.
Meanwhile, at the plankton ecology station, the fifth graders collected a plankton sample and examined it under a video microscope, identifying many zoo- and phyto- plankton from single-cell organisms to complex species. At the hydrology station, they collected top and bottom water samples, and measured salinity, temperature and density of the bay.
The students rotated through all stations in collaborative learning groups. The students enjoyed seeing each group’s catch, the highlights of which were leopard sharks, sting rays, halibut, and torbets. This experience brought to life many of the science concepts the 5th grade has been learning this year, centered around earth’s spheres, hydrology, life science/animal food chains, adaptations, and human impact on the natural world.