The Final Countdown

   We are finishing up our trip around Florida at UNF, and so far this week has been full of activity and excitement! I honestly have to look through pictures to remember which things were on which days! On Monday we departed in two UNF boats - The Osprey and Genetic Drift - and performed water quality testing along the St. John's river.

The Osprey

At the mouth of the river we found that the salinity was very high, at around 35 ppt (the ocean water itself is normally around 35 ppt). But at the farthest location we went to - about 20 miles down river - the salinity was around 1 ppt! The salinities were so different from each other but we hadn't even travelled close to the full length of the river.

Our data!

Many human impacts affect the river, and we noticed this as we continued down the length of it. Septic tanks - which are supposed to filter human waste - actually stop working after many years, causing both bacteria and waste to be released into the river. Other issues like runoff, and breaking down of iron on shipyards along the river also add to our impact on the river, making it one that you would not want to swim in! Some of the areas along the river are very urbanized, but others have marshes along it's shoreline. Hopefully in the future we can find solutions to having this urbanization but limiting the waste.

We went under many bridges along our route

The Jacksonville Landing is located right off the river

  On Tuesday we went to five very different beach locations. Our first stop was one of the locations that Juan Ponce de Leon is said to have first landed.

This location had very tall dunes, and Guana was visible from the top of the boardwalk, in the opposite direction from the beach. We discussed how Northeasters are actually more damaging than most hurricanes to this coast. Northeasters are huge rotating storms, like hurricanes, that originate in the north and do not rely on development in the tropic region. We also learned about the sand on Florida's beaches being from coquina rock, and at the last site we studied large coquina outcroppings - they were very cool and I had no idea that we had anything like that on our beaches! This first beach was unique because it was on four miles of uninhabited land, which is great for sea turtles nesting, as well as other animals. There aren't very many beaches like this.

The dunes were very tall and house a number of organisms.

Our second site was Vilano beach. This beach was opposite from the first in several distinct ways. First, it was nearer to St. Augustine (right next to the St. Augustine Inlet) and was not in an uninhabited location. As if to emphasize that, cars are permitted to drive and park on the beach! What?! I had never even heard of doing that before, but when we arrived there were several cars parked on the beach and several more arriving and following suit.

 A second large difference was how flat the beach was. The first beach had huge dunes, but this one was very flat (from beach nourishment) and had much less plant diversity and abundance in the dunes. Thirdly, this beach had a jetty, and used beach nourishment programs, dredging, and was on an inlet.

Our third site was at Matanzas Inlet. This inlet is different from the last because it is natural - there is no dredging or jettys, and the inlet has already migrated as sediment deposits on one side and erodes from the other. There is a bridge that used to pass mostly over water, but now it goes over mostly sand.

A small piece of coquina rock.

The reddish orange color on the sand is shell hash (lots of tiny broken up shells!)

Erosion on the dunes, and the bridge in the background.

The erosion in the picture above is likely correlated to the "super moon". A few nights ago the moon was very close to Earth, causing more severe tides - higher highs and lower lows. This causes the water to reach the dunes and erode them.

Natural inlets like this one are great for nesting birds. We saw several guarding their nests. Oddly, these birds do not feed in the ocean, but choose to live near it.

Nesting Tern.

Our fifth location was a channel that closed around 2008, leaving several homeowners' docks in the sand, instead of water. At this site there were hundreds of fiddler crabs, and small black mangroves growing in - which means that these houses will not be able to dredge and return the water, because the area has become habitat to natural species.

Hermit Crabs on the move!

A sandy boat dock - bummer!

To finish up Tuesday, we went to one of two natural coquina outcroppings on the east coast of the United States, and it was beautiful! They used to be underwater thousands of years ago, and similar to reefs. We found many different organisms making these outcroppings a home; including barnacles, Sergeant Majors (again!), crabs, algae, and more.

Barnacles on the coquina outcroppings.