A Tale of 'Slim Pickins'
by
Dr. Ellen, Slim's Adopted Human

A fine old Great Blue Heron (Ardea herodias) has been hanging around the headsprings of the Rainbow Springs Aquatic Preserve for many years; some locals say for 20 years, which could be the case since Herons can live that long. The oldest great blue heron of record was said to be 23 years of age.

Their average lifespan, however, is more like 15 years.

As is the case with most wildlife, this species is extremely vulnerable when young; more than half the great blues born each year will die before they are a year old.

Locals call this guy 'Slim' because he is old and thin and he has less than perfect eyesight. How do we know all that? Well, Slim is missing a long toe on his right foot; probably from one of the many large snapping turtles that live in the river. He is therefore easily identifiable when standing on one of our docks in our quiet river neighborhood. You will learn more about his poor eyesight below.

Slim swoops in every evening around at dusk and lands in the shallows near my dock, sometimes before I even get down there. More often, though, I see him on the opposite bank of our narrow river waiting patiently for me to appear. If there is inclement weather he arrives earlier in the day but he still comes like clockwork!

Slim is a master of ritual. After landing in the shallows he inches his way into ever slightly deeper water where he will then stand motionless for 8-10 minutes at a time, trying his best to look like any other blade of river grass. His long legs bend so as to disappear into the depths and his neck turns so spindly that even I can occasionally loose sight of him!

That said, he is not the best fisherman any more. So I buy loaves of day-old bread and I “work” the fish around our dock. That idea came from a psychologist friend, don't you know. There are so many brim around the dock that when the brim see the bread hit the water they come bubbling up to the surface in large numbers.

Occasionally there will also be a big old Bass or two in the mix, and some turtles, not to mention a passing Anhinga or two who duck and dive for their own share of the swarming brim.

The feeding frenzy of brim on the surface of the water definitely gets Slim’s attention.

I start by throwing balled-up bits of bread close to the dock where the fish hang out. Then I throw bread balls farther and farther out from the dock to where Slim is standing in the shallow grasses. The brim follow the bread trail, which draws them ever-closer to the shallows that they would otherwise avoid (for good reason). Gulping these taste treats creates ever-widening ripples and splashes on the water’s surface as Slim watches with great interest.

Can you spot him in the grasses on the far side of the red canoe?

Some nights Slim doesn’t catch a fish, poor guy.

And then again, some nights he catches one and occasionally two big fish. It is fun to watch him.

With a fish firmly clenched in his mouth, or sometimes speared by his long pointed beak, he backs up to the beachhead where he safely flips it around and swallows it whole, head-down into the gullet.

And almost always he gets a quick drink or two of water before resuming his fishing posture in the protective grasses like you see below.

NOTE ABOUT FISH VISION: According to studies of fish vision, fish can easily see prey at very low light levels. And despite their differences in habitats, humans and fish have very similar eyes. Light is diffused in water but the water in Slim’s case is from one of Florida’s most pristine springs that has exceptional water clarity.

Science doesn’t know exactly what fish see but I can tell you from my dockside experience over many months that they perceive the slightest movement, which is why Slim stands so still for so long, hoping that they will forget about him.

I always clap a few times and yell BRAVO! as Slim saunters back from his first course. Unpreturbed, he just stands there, head cocked to one side on the lookout for another fish, paying me not the slightest bit of attention.

Boats going by are distracting, especially if they leave a big wake which means that he probably won’t catch any more dinner that night.

Wakes scatter the brim.

But most recreational boats have left the river by 7:00 pm or so, so it is just the a neighborhood fisherman out there at that time of day but -nonetheless- I wish they would go home. I certainly don’t let them see all the brim bubbling up at the surface of the water or they would hover around my dock for hours!

If Slim misses his mark, which he does fairly often, the fish scatter as his body noisily hits the water with head submerged. And I then have to start the brim behavioral modification program all over again.

I do go through a lot of day-old bread on old Slim's behalf!

I hope Slim lives a very long life because the river will not be the same without him. You know I'm hooked when, even on stormy rainy days, I head down there with that big ole' bag of bread, oftentimes with Slim coming up the walkway to meet me...

Dr. Ellen

MORE SLIM IMAGES

LEARN MORE ABOUT THE GREAT BLUE HERON:

The Great Blue Heron (1997) Book by Robert W. Butler - Considered the best, most comprehensive information about the Great Blue Heron; beautifully illustrated, a treasure for Heron lovers

Facts about the Great Blue Heron at the Cornell Lab of Ornithology

Herons in the Florida Everglades

The Critter Catelogue (for kids) on the Great Blue Heron

The Great Blue Heron Fact File at Wildscreen Archive