Hart Springs is very different from both Fanning and Manatee Springs, even though it’s just upstream from both.  Although its discharge is comparable to that of Fanning, it has several noticeable differences.  First, Hart Springs is a county park rather than a state park.  It appears that many private/county parks have less tree cover around the boil and that they are more likely to have cement reinforcement along the edge than most state parks.

Second, apparently Hart Springs is one of those unique Suwannee springs that reverses flow so that brown Suwannee water occasionally comes out of the vent.  I was told when I arrived that the water had just cleared up.  I also read that the discharge of Hart Springs had been restored by divers who removed some debris that had fallen into the main vent (http://hartsprings.com/2016/01/26/gainesville-sun-article-about-diving-at-hart-springs/).  I’m not sure if the higher stage (as evidenced by the water over the “island”) was a function of the increase in discharge or just seasonal variability.  Apparently, the spring is often much clearer than the day that I visited.

Third, it does not appear to have the massive vents that the other two springs have.  Instead, it has at least three vents, and perhaps a fourth that was not flowing (there was a side arm that looked like it might have a spring in it).  However, given the murky water, it may be that the middle vent really is as big as Fanning or Manatee, but I just couldn’t see it well enough.

This video really stinks because the water clarity was so low, but this vent appeared to be the biggest of the three.  I also managed to knock the camera off kilter and get the leash in view.  It was rainy and cold–oh well!

This video also stinks because I couldn’t see what I was videoing, so view isn’t great, but this is the smaller vent next to the large one.  It was the vent nearest to the entrance to the park.

I only found this vent because the surface of the water was disturbed.  Again, the view isn’t great because I couldn’t see!

I liked the run; it was longer and more intimate than either Manatee or Fanning.

The Hart Spring run in the rain.

Hart Spring had a much smaller entrance into the river than Manatee or Fanning, even though it had similar discharge to Fanning (75 cfs, according to Scott et al. 2004, “Springs of Florida”).

Given that it’s in a similar landscape to Fanning, I had assumed that the nutrient concentrations of Hart would be similar to Fanning, but the nitrate concentration of Hart was quite a bit lower (1.1 mg/L for Hart as opposed to 3.7 mg/L for Fanning according to Scott et al. 2004, “Springs of Florida”), at least in 2004.  The phosphorus concentrations were similar and fairly high (~0.07 mg/L according to Scott et al. 2004).

The fish assemblages of Hart and Fanning were somewhat similar, except that Hart did not have many of the larger fish that I observed in Fanning, with the exception of striped mullet (Mugil cephalus), which seem to be in every spring with a connection to a big river.  In both springs, I saw relatively few large fish (except mullet) and a lot of algae.  There were, however, a million turtles in Hart Spring.

Turtles getting startled by my approaching kayak.

And there were a billion snails.  They appeared to be banded mystery snails (Viviparous geogianus), which are the snails found in the Native American middens.

Banded mystery snails dotting the sediment near the mouth of Hart Spring.

And, surprisingly, given that I never saw them, there were two manatees!  I was stunned when I downloaded the video.  I had paddled out into the river just a tiny bit so that I could test the water temperature and the dissolved oxygen concentration in the river.  As I was paddling back in, apparently, I also startled the manatees.

Manatees swimming out of Hart Spring and back into the brown Suwannee River water.

I also caught another swamp darter (Etheostoma fusiforme) on video.

The swamp darter swims out of the vegetation in the center of the video and lands on a stick at the bottom of the image.  The other fish swimming around are some kind of shiner (Notropis sp.).