Manatee Migration: 430 Manatees and a Big Alligator
What is going on here? An alligator perilously close to two Yellow-bellied slider turtles. The alligator was there first. The turtles climbed right atop the alligators snout, indicating that this type of turtle is not a favorite meal for alligators though they could easily eat the turtles. Alligators preferred food are fish and small mammals (like raccoons).
On a recent afternoon at Blue Spring there were a reported 430 manatees, several really big alligators and hundreds of turtles seeking warmth in the springs relatively warm 73°F (23°C) waters. Nighttime temperatures have been in the 60°s dropping the nearby St. Johns River's water temperatures into the 60°s. Manatees lower temperature limit is 68°F in order to maintain a safe internal body temperature. If they are in water any colder for an extended time period they develop "cold stress," which makes them vulnerable to disease and death.
The sign at the entrance to Blue Spring announced 430 manatees in attendance on this warm afternoon (air temperatures in the mid-80°s). I quickly counted 431.
Blue Spring historically discharged around 100,000,000 gallons of 73°F (23°C) water every day providing a warm and safe refuge for Florida manatees in winter. Technically called "Volusia Blue Spring" locals refer to the spring simply as "Blue Spring." Historic flows at the spring averaged 162 cubic-feet-per-second or about 105,000,000 gallons per day prior to 1980. Spring flows since 1980 have been significantly lowered by uncontrolled development. Recent flows have averaged closer to 80,000,000 gallons per day.
The spring run provides critical habitat for the endangered West Indian Manatee (Trichechus manatus; aka "Florida Manatee"). The spring discharges from the Upper Floridan Aquifer through a spring vent situated 20-feet beneath the land surface.
Manatees are vegetarians and there is nothing for them to eat in the Blue Spring Run, so for the most part they stay close to the area where the run meets the St. Johns River. In the river there are abundant aquatic plants for the manatees to eat.
Boaters and Kayakers watch the manatee migration at the confluence of the Blue Spring Run (to the right) and the St. Johns River (left). 3 miles north on the river is Lake Beresford.
Yellow-bellied slider (Trachemys scripta scripta) turtles, native to Florida, are excellent climbers. They have long claws that allow them to climb high onto logs and trees to get some sun on winter days. In summer they sun for other reasons such as shell health. Read more about why turtles bask at the link below.
I count 7 yellow-bellied sliders, 1 big alligator and a florida manatee in this shot. Hint, the manatee is in the foreground near the alligator with his nose sticking out of the water.
The further I pull the camera back the more turtles I see basking around this alligator. Here I count 8 turtles.
Another angle of view of this prime reptile real estate in the Blue Spring Run.
A yellow-bellied slider shows his claws here where he has climbed high atop a tree limb above the Blue Spring Run.
I watched the alligators for a long time, sunning on logs surrounded by yellow-bellied sliders and manatees. If these alligators had been really hungry I doubt the scene would've been quite like this.
There are many manatees on the bottom around this alligator. The grey blobs in water that look like boulders are Florida manatees.
Hiking Blue Spring
Hiking at Blue Spring isn't so much about hiking but more about walking through the hammock high above the swamp on an elaborate boardwalk. Its about a mile into the swamp to the vent (or boil) of the spring.
Along the way one can see all sorts of fish. The fish annoying manatees the most are the non-native (invasive) Vermiculated sailfin catfish. What we used to call sucker fish when they were sold in pet shops to clean aquarium glass. Here they grow large and prehistoric-looking.
At the spring vent you'll see few if any manatees except for the coldest days of winter. There is nothing for manatees to eat in the spring run so they mostly stay close to the river where aquatic plants are abundant.
An unprecedented feeding plan comes as more than 1,000 manatees—about 15% of the state's total population—have died this year so far
Want to blame someone for manatee deaths? Look no further than the Florida Governor's office. Governor DeSantis continues to refuse to slow development in critical manatee habitat areas and refuses to ban the use of artificial fertilizers in manatee watersheds.
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