Sunday, 4 June 2017

Week 3: FGCU

The adventure continues at Florida Gulf Coast University. Our primary focus here was the seagrass and oyster beds of Estero bay. Doctor James Douglas worked with us on Monday and Wednesday, taking samples off the bay floor from several different locations. Monday we retrieved 12 lift nets he had deployed a few days earlier. These were nets attached to a PVC pipe frame and filled with old oyster shells. The idea is to place them in a habitat and leave it, allowing organisms to move in and inhabit the shells. Then after pulling it up you can get a fairly accurate survey of what lives in these ecosystems. After pulling the lift nets we went back to lab and identified what organisms we could. This data gave us a pretty cool picture of what the benthic species composition was like on these oyster reefs. Wednesday was a similar process, except this time instead of using lift nets we directly sampled the bottom using a Vernstine device. We also took small core samples to get an idea of the organisms living under the sediment at each site. The majority of these sites were seagrass or muddy bottom environments. Between the samples taken from these two sites, we got a fairly good impression of the types of organisms living across the bottom of Estero bay.
Beyond sampling the bottom, we also went out with a geologist on Tuesday and took a core sample off of an oyster reef. This was super cool because the core showed a distinct transition from terrestrial to marine, and the process of biological succession into a oyster reef. The same day we also hiked on mound key, a large island that is thought to have actually been built up by the Colusa. The Colusa were a large Indian tirbe who had a massive presence in the area. Mound key was the de facto capital for the Colusa, making it a particularly good spot for archaeological digs.  We got to see one of these digs, as well as some of the other key locations unearthed around the island. Diving into the both the archaeological and geological history of Estero bay in one day was a really unique experience. Thursday was the last actual field day. We all split up into canoes and paddled out across different sections of the bay. We then deployed high tech flotation devices (i.e grapefruit), and measure the distance the floated over 10 minutes using a gps. Using this data we then attempted to map the currents in estero bay during an incoming high tide. However in practice user error and gps inaccuracy gave us some very inconsistent data. It was still cool to see how the process works, and I always enjoy a good canoe trip. This week covered a wide range of topics and methods. It was very involved, but also very rewarding. Next week we move on to USFSP, and I can't wait to see what else is in store.

1 comment: