Searching for Florida Panther Tracks

Looking for a good way to get the attention of airport security? Try bringing a half-gallon Ziplock bag full of an unmarked powder in your carry-on bag.
Agent: "Sir,what is this?"

Route 29, South Florida
June, 2016

 Me: "Plaster of Paris."
Agent: "And why do you have it?"
Me: "To make casts of animal tracks."
Agent: "What?"
She recommended next time I fly, I take it out of my daypack for easier screening...

I was heading to Tampa, Florida to attend a business meeting but had managed to arrange exactly 25 hours of free time before the opening session to head south and search for Florida panther tracks. That meant a three-hour drive each way once I arrived in Tampa. I sought advice before heading out on where to go. One spot that looked promising on a map was a highway underpass leading from Fakahatchee Strand Preserve State park to the Florida Panther NWR under I-75. My plan was to park to the south near what appear to be flooded quarries in the Northeast corner of "Fak" and hike the two-track to the underpass rather than try to drive the low-clearance rental car on any of it.
I arrived at the hottest part of a (to me at least) very hot and humid day. I have never been to Florida in June and everything appeared to my eye to be very wet. The trail quickly produced domestic dog tracks, similar in size to the panther tracks I sought, and this allowed me to brush up on my canine v. feline track ID skills.
I feel there is much misinformation regarding how to tell cat from dog tracks. For example, many people put far too much stock in whether they see nails or not. First, not all dog tracks show the nails and second, lay persons often do not recognize nails even when present. Consider the dog tracks I photographed only minutes into my hike:

Domestic dog track
Fakahatchee State Park, FL June, 2016

If you look closely at the track above, you can see the nail marks on the left side of the track but I cannot see them on the right side at all.

Domestic dog front (lower track) and rear (upper track) paw prints
Fakahatchee State Park, Florida June, 2016

I followed the trail largely with my head down looking for sign which is not the best way to stay aware of one's surroundings but perhaps a forgivable sin considering the singular purpose of this hike. The trail was a maddening mixture of wonderful muddy substrate followed by long stretches of difficult limestone bedrock. My eyes strained to find recognizable detail in this unfamiliar ground when suddenly a bird leapt up from my very feet. I instantly registered "goatsucker" (the common name for the family Caprimugliformes) as I watched it settle on the trail 15 yards ahead. But which species? It took to flight and the white wing patches confirmed Common Nighthawk.

Common Nighthawk
Florida, June 2016

Common Nighthawk
Florida, June 2016

 I pressed on. I knew from the aerial view on Google Earth that the trail would bend north ahead and i was prepared for the mud, brush and mosquitoes I was to encounter as the trail became less used and more narrow. What I was not prepared for was two feet of standing water. The water stretched as far as I could see and I had at least a half-mile to go before reaching the underpass. I considered continuing but realized that the underpass was probably underwater as well.
It was only a short drive to my next stop. Also in the northeast corner of "Fak" there is an unmarked road that ends at a gate. The road provides access to a few private inholdings and makes for a nice hiking trail for the public. By now it was late afternoon with temperatures and percent humidity still reading in the mid-90s. My glasses, camera and binoculars all fogged while making the transition from the air-conditioned car. I applied more sunscreen and donned my camouflaged bucket hat; the one I plucked from the Indian Ocean while snorkeling in Australia a decade ago. My pack was heavy with plaster, water, camera and field guide. But my spirits were light as I hoped for success.
Facebook friend, fellow blogger and all-around naturalist Janet Pesaturo had recommended this trail to me. She placed camera traps here in January and wrote about her results on her blog here. It didn't take long before I found my first set of tracks. And they were CAT TRACKS!
I guess I knew they were bobcat from the moment I saw them but I still carefully measured them and consulted my field guide. On page 208 of Elbroch's Mammal Tracks & Sign, the author states that the

Bobcat track
Florida, June 2016

heel (or palm or metacarpal) pad of a bobcat measures 1-1 9/16 inches while a panther would be larger. Since toes can sprawl, the heel pad is a more reliable measure than overall track width. These pads were just under 1 1/2 inches, not even at the high end of bobcat so my initial impression was confirmed.
What made me so certain these were feline? First, they show an asymmetry that canine tracks do not. Picture your four fingers without the thumb and you have the toe pattern of a cat. But there are other characteristics too. Look at the shape of each toe. They are nice ovals. The leading toes of most canines are oval but the outer toes of canines are not. Those toes have an inner edge that points toward the center of the track. Panther toe prints are compared to grapes in both size and shape.

Front right Bobcat track
Florida, June 2016

In addition to the toe shape, look at the heel pad shape. Canids have a single bump at the front while felids have two. Sue Morse's trick to remember this is to think of the double bump as the letter M for "meow". It works.

The thunder rumbling in the distance had been barely registering in my mind but as I looked up from the bobcat tracks I noticed an ever darkening sky. I decided to press on but 20 minutes later i saw that I could no longer ignore the incoming thunderstorm. I turned back and reached the car just as the first fat drops of rain began to fall.
The 15 minute drive to the motel in Everglades City was a wet one. It had been a rainy week before I arrived and I saw standing water in every parking lot. I grabbed some food to go and waited out the weather in my room.
A night drive after the storm produced lots of snakes but no mammals. The following morning I was back in my same parking lot at the gate ready to press on where I had to turn back the day before. I relocated the bobcat tracks and they showed that this spot was on the edge of last night's storm as the tracks had not changed much. I continued past the point I reached the day before and quickly found rodent tracks of both gray squirrel and what I believe were hispid cotton rat. A Barred Owl was hooting and I began to spot small alligators among the cypress knees. As I bent to inspect yet another muddy spot, my heart skipped a beat as I saw a clear tow print the size and shape of a grape! Then another. And another. And two more. Wait.... that makes five. My mind screamed "black bear" but I

Black Bear track
(Florida, 2016)

fought that identification with all my might. Surely this was to be my elusive panther! But it was not. One track became two, that became a short trail. Not a Florida panther for sure, but who can remain sad while looking at fresh bear sign.
I pressed on. I found more bear tracks. I birded. I softly grunted to the alligators, imitating the call of the young. I looked in vain for panther tracks. I was lost in thought when I realized I was hearing running water. Ahead the trail was blocked. My search had come to an end. Walking back, I discovered a camera trap, crouched down in front of it for a selfie, and sent Janet a Facebook message asking if it was one of hers. It was.
The drive to Tampa was long but uneventful. I decided I had to return to that trail when there was less water. That night after dinner, I found the passage I was looking for in Maehr's 1997 book The Florida Panther: Life and Death of a Vanishing Carnivore": "We were standing in the heart of the only place east of the Mississippi River where this combination of terrestrial carnivore species - panther, bobcat, and black bear - still live." I smiled at the thought that I had stood there too.