Category Archives: Species Profiles

Clarkii By County: Miami-Dade

In anticipation of an upcoming article on the Salt Marsh Snake (Nerodia clarkii) in Herp Nation Magazine Issue #18, and the (hopefully) near completion of the data-gathering phase of my research on clarkii in southern Florida, I’m going to review some of my experiences with the species. Instead of a smattering of stream-of-conscious ideas and such, I’ve decided it would be interesting to systematically review what I know of the species in every Florida County I’ve come across them in. For my readership, I think the interest will be in the fact that a.) the foraging and movement ecology of clarkii seems to be different on a local level, in other words they simply act different in nearly every county; and also the pattern and coloration is extremely variable across their range (more elaboration in future postings, and of course the upcoming Herp Nation Magazine article.) So sit back, relax, enjoy.

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Let us begin from the familiar: Dade County – Everglades National Park. Yes, there are other sites in Dade from which to view clarkii, but ENP is rife with them and many herpers have seen the species there. For this reason, I’m sorry to inform you that if you’ve seen clarkii in ENP, you may not have seen clarkii. From our work so far, we’ve encountered 19 Nerodia clarkii-like animals there, of which sixteen have been hybrids between N. clarkii and the Florida Watersnake, N. fasciata, and only three have been pure clarkii. This is one of the interesting things about the species: they readily hybridize with Florida Watersnakes, especially in large-scale mixing zones such as the Everglades. Our work initially began in ENP where we were testing the use of traps for detecting clarkii. Without giving away the data, the interesting tidbit about clarkii at this population is that road cruising seems to be the best way to come across them, and it also seems to be one of the only productive ways to turn them up. Of course I’m not saying it’s impossible to hike them up in ENP, they certainly forage, eat and live outside of the roadways. However, perhaps because of the dense mangroves with extremely deep mud that makes the habitat difficult to search, or perhaps because they forage at different times or in different manners from other populations, we found only a single clarkii by hiking, despite much time spent looking. (And full disclosure: the clarkii we hiked was on a right-of-way, meaning it would’ve been road cruised in seconds had we not already been out of the car.)

Dr. Chesnes checking a trap for clarkii

Dr. Chesnes checking a trap for clarkii


Now on to the variation. Holding with their hybrid nature, most of the clarkii encountered in ENP are banded in some way:

Pure clarkii:

15263277375_149118d244_z clarkii x fasciata:

8737089472_6c2c5caeb1_zPure clarkii:


clarkii x fasciata:  8737101614_ea45180a5e_z

However, occasionally one will look a little more classic clarkii (not that I know what that is, and I can’t seem to find a great picture of one.) And it seems that the red trait is not a recessive one even when fasciata is in the mix, and hybrids will still often turn up with a clarkii bloodred coloration: this individual was a clarkii x fasciata:




That’s all for this segment, in the weeks ahead we’ll take a gander at Indian River, St. Lucie, northern and southern Monroe, Collier and Lee Counties – and maybe, just maybe a new county record or two. Don’t forget to check out issue 18 of Herp Nation Magazine, coming out in a few months for my article on Mangrove Saltmarsh Snakes (



NOTE: This research on Nerodia clarkii was partially funded by a Palm Beach Atlantic University Quality Initiative Grant, so many thanks to them. To help us continue our last few months of research, please consider making a small donation to Field Ventures



Species Profile: The Mangrove Salt Marsh Snake

We have four watersnakes of the genus Nerodia in my neck of Florida: the Green Watersnake (N. floridana), the Brown Watersnake (N. taxispilota) the Florida Watersnake (N. fasciata pictiventris) and the black sheep of the family – the Mangrove Salt Marsh Snake (N. clarkii compressicauda.) Why are Mangrove Snakes the black sheep of the family? There are actually a lot of reasons: despite the fact that it is closely related to the Florida Watersnake – and even readily hybridizes with them in the wild, the Mangrove Snake is quite a different animal.

Despite the “watersnake” designation that the genus Nerodia carries with it, Mangrove Snakes can’t be fully classified as aquatic: semi-aquatic, yes, but the fact of the matter is they will spend quite a bit of their time resting on the boughs and proproots of Red Mangroves (Rhizophora mangle) – they are indeed a semi-arboreal watersnake. The oddity doesn’t stop there either: anyone who’s ever handled a wild Nerodia of nearly any species will attest to the genus’ poor manners. That is to say, it is not uncommon to face the piercing of a watersnake’s teeth, the sting of the subsequent musk in the wounds and the steady drip of blood thanks to their anti-coagulant laden saliva. However, of the dozens of Mangrove Snakes I’ve handled during the research for my field guide and subsequent projects, I don’t recall once having been bitten by any of these docile snakes. Then there are the morphological differences: Nerodia clarkii compressicauda possesses a range of pattern and coloration. Sometimes they look vastly different from any other watersnake, sometimes they are nearly indistinguishable from the Florida Watersnake. Banding or striping, red, black, orange, yellow and grey are all within the natural variation for the species; perhaps surpassing even the Cornsnake in its range of natural variation.

The Mangrove Snake is a species I’ve been working with a lot lately both in the Everglades and the Florida Keys (I know, life’s tough.) The nature of their habitat choice with its high structure and ever-shifting tides, as well as their semi-arboreal habits begs the question of how best to survey for them: typically, Watersnakes are most efficiently and quantitatively surveyed for using aquatic trapping methods, that is, commercial minnow traps set in the water. My current work involves looking at the efficacy of this method when compared to foot and road survey methods. Like any organism; when one dedicates time to their study – to getting to know a species both in the scientific sense as well as the deeper knowledge of a species that can only come from observing and interacting with them in the field – that species becomes exponentially more interesting.

For those who have never had the pleasure of seeing a wild Mangrove Snake, I cannot express how thrilling it is to see them on the road or draped over a mangrove proproot – they are one of Florida’s finest, and I would recommend any herper add them to their lifelist.


Posted by on 03/04/2013 in Species Profiles


Exotic South Florida Part V: The Veiled Chameleon (Chameleo calyptratus) in Florida

Well, based on the lovely statistics that WordPress sends me, most people find my blog by searching for “Chameleons,” it would seem. Well, there are other species other than the Oustalet’s Chameleons (which I’ve talked about previously) here in Florida. The most well known, and perhaps most dear to my heart, is the Veiled Chameleon. Well known because they are widespread (In at least 5 counties, by my reckoning); and dear to my heart because they are, in fact, the one animal species I have been shot at while looking for.

These chameleons from Yemen have been in the pet trade for a number of years. Though they can often be expensive and/or tedious to keep in captivity, they thrive in southern Florida for a number of reasons. Of course, food is typically abundant in the disturbed habitats where they thrive, and chameleons are slow, yet deadly predators; however the real thing that has a potential to limit their distribution is the cold weather. They can succumb to frigid temperatures just like any other reptile: Veiled Chameleons, however, have a trick up their sleeve. They have the ability to burrow down – up to several feet – under the ground, and will readily use this ability to find refuge from frost and extreme cold. There is yet another use for this magnificent adaptation: they will use the same excavation ability once full grown (which takes less than a year) to make a safe, temperature-buffered chamber in which to lay their dozens of eggs. And I mean ‘dozens’ most literally: one individual I found a few years ago laid about 70 eggs.

By one way or another, it seems the hardiness of these chameleons became well known and they began to be spread by helping hands across the southern peninsula of Florida and eventually some of the populations began to be published (See Krysko et al, 2004). And, once published these sites attracted many more visitors – some not observing the trespassing laws, jumping fences and wreaking havoc with concerned locals.

Interestingly enough, though these lizards are certainly exotic, at times hard to find, and can have voracious appetites; I haven’t seen any evidence as-of-yet to suggest that they are invasive. To be clear: an exotic species is not necessarily an invasive species. In fact, as far as is known the majority of exotic species that end up getting released into a new environment die off rather quickly, and a majority of those that do survive will not be able to find a mate and reproduce. But even if an animal is able to reproduce in the wild, it still may not meet the distinction of being invasive. According to the USDA, an invasive species is one that is “non-native (or alien) to the ecosystem under consideration and whose introduction causes or is likely to cause economic or environmental harm or harm to human health.”

Does the Veiled Chameleon meet these criteria? Perhaps it will be found to, but given the evidence at this point in time we cannot but sure, so it would be premature at best and completely false at worst to label them such. These are a species which thrive in disturbed habitats in Florida, habitat which is often comprised of mostly exotic plants to begin with; and even so it is not entirely known what they eat in Florida: many keepers of the species note their affinity for eating brown anoles in captivity, an invasive species itself, and a species for which the south Florida ecosystem would benefit from reduced numbers.

Now, I don’t make this argument as an activist of some sort who is “pro” having chameleons in the wild in Florida, I only wish to make the point that we do not know. It would be a mistake (and a common one) to assume that this lack of knowledge means that the Veiled Chameleon is a completely harmless exotic; and it would be equally foolish to assume that this is an invasive species here. For myself, the lack of knowledge more than anything is an invitation to let curiosity run wild and seek out the truth of the matter: to delve deep into the species, to watch and to study it. And hopefully one day, to know it – that is the essence of why I became a biologist in the first place.

Krysko, K. L., K. M. Enge, and F. W. King. 2004. The veiled chameleon, Chamaeleo calyptratus Duméril and Bibron 1851 (Sauria: Chamaeleonidae): a new exotic species in Florida. Florida Scientist 67:249-253.


The Coastal Dunes Crowned Snake (Tantilla relicta pamlica)

Tantilla relicta pamlica looks just about like any other tantilla; which are typically pretty diminutive and unimpressive snakes themselves, but the Coastal Dunes Crowned Snake is nevertheless a special snake. They are endemic to the southeastern coast of Florida from Brevard to Palm Beach County, unlike the other subspecies Tantilla relicta relicta and T. r. neilli which can be found from the south-central part of the peninsula northward.

Coastal Dunes Crowned Snakes are rarely seen, and anyone who’s visited southeastern Florida can tell you why: only a small part of their range still possesses the scrub, hammock and other habitat they need to survive. Not that this 6-10 inch snake needs much room to survive, but when your home also happens to be the best place on Earth to build a condo; someone’s going suffer – and in this case the animals with limbs and bulldozers win.

Fortunately though, there are some abandoned lots here and there, natural areas and state parks where these and other species hang on, hopefully indefinitely. It is in one of these places where I found a Coastal Dunes Crowned Snake, the last snake taxa I had left to find that is native to my county. I had been hiking and thought to myself how similar the habitat I was in looked to the habitat I find Tantilla in when in central Florida. I mentioned it to my wife and looked under a couple logs here and there. As we continued on, I spied a water spigot that looked like it may have dripped occasionally onto the small concrete slab below it. In the sandy soils of Florida, finding a source of water is objective #1, especially if you’re a small and easily dessicated snake.

Yes; I thought to myself, that slab surely provided the water and centipede prey that Tantilla need to survive. Ninety-nine times out of a hundred, such a thought will occur to me and I will flip that rock and it will be completely empty underneath. But one in a hundred times or so; something amazing will happen. Can you guess which happened this time?

Sure enough, a little sandy-colored snake wriggled by and into the sand under the rock. With that, and a few pictures, I was on cloud nine. Granted, a few year ago, I’d think it insane to get excited over such a little thing; but perhaps with some maturity in herping one comes to appreciate the little things. I let the little fellow on his way and continued on my way, happy to know that there’s still room for an tiny, endemic wonder such as Tantilla relicta pamlica.

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Posted by on 30/12/2012 in Species Profiles, Tales From the Field


Species Profile: The Striped Crayfish Snake

Striped Crayfish Snake


The Striped Crayfish Snake (Regina alleni) has always held a special place for me. The reason being it was the first snake that I actually road cruised on my own when I first moved to Florida. It was mid-October and I was asking around about places in the middle of nowhere to drive around for snakes among my college professors. One suggested Corbett Wildlife Management Area, and that evening I was off and cruising about 5 miles of the road in my small sedan (the road itself is something like 20 miles long, but was mostly flooded.) Sure enough, I found three strange snakes in that five mile stretch; all of them Striped Crayfish Snakes.

Over the past seven-or-so years since, they’ve been a regular sight when traversing wetlands to and fro: never abundant, but also seldom absent with enough effort. I’ve often wondered if these snakes are perhaps really abundant and just very cryptic (in layman’s terms: really good at hiding,) or if they are as uncommon in southern Florida as road cruising surveys would suggest. The reason behind this thinking is that their primary food, crayfish (Procambarus alleni and Procambarus phallax, in southern Florida), are extremely abundant. Now, of course, food isn’t the only limiting factor for whether a species is abundant or not – predation, territoriality and a hundred other factors contribute to this. That said, I still always suspected if you could strip away all the vegetation, muck and other composition of a freshwater marsh in the Southeast, you would find a ton of Crayfish Snakes.

Now, I didn’t (nor will I likely) get a chance to do the aforementioned destructive experimentation, but I got close enough recently with the high waters related to Tropical Storm Isaac (see some of the effects here: – this trail is usually high and dry.) With these high waters, I began to notice numbers of DOR (dead on road) Crayfish Snakes around my field site every time I went out. One particular night, I had to check some traps and happened to be on the road at “prime time” where I saw one Crayfish Snake crossing the busy road. So, I stopped the car and went to grab it. I was curious as to whether there might be more out, and I walked 10 feet or so down the road’s shoulder and sure enough: another Crayfish Snake. My dear wife, Beka, was gracious enough to let me walk a ways more, and to even join me in my walk: we ended up getting 21 snakes in about 30 minutes, 10 of which were crayfish snakes.

To be clear: the most crayfish snakes I had gotten in one evening were the three from Corbett seven years prior. I had more than tripled that number: wow! The disappointing part of this Crayfish Snake movement was that I could see it had been going on for many days: fifty or more DOR Crayfish Snakes littered the sides of the road where I walked. So, I aspired to get out again the next night and save as many as I could. I rounded up a posse of 6 other people and we walked the same route as before: this time we turned up 24 snakes, 9 of which were Crayfish Snakes.

What could have caused such a mass migration of snakes? I can only speculate, as I’ve tried asking the snakes in question and gotten only tongue-flicks in response – Crayfish Snakes, like most aquatic snakes, do have to dry out every now and again otherwise they will break out with blisters all over their body: so it may be that they simply ran out of places to dry themselves with the high waters and were forced to take to the roads. It could also have been related to reproduction: of the 19 live Crayfish Snakes caught over those two nights five were heavily gravid, with another several possibly gravid. But really, when it comes down to it, I don’t know why all these Crayfish Snakes are abandoning their aquatic haunts and coming onto roadways; other than I think it has something to do with T.S. Isaac. But this mass movement provided a great opportunity to learn some more about a beautiful and interesting animal.


Posted by on 15/09/2012 in Species Profiles


Species Profile: The Greater Siren (Siren lacertina)

A quick species profile while it’s on my mind:

I spent an evening this week with old herping buddies of mine, Donald Filipiak (Check out his photography – ), and Josh Young in search of aquatic herps. Typically, this is undergone by trapping them out of their territory (Dip netting,minnow traps, etc.) but we met them in their own habitat and walked for a good bit through some shallow Everglades ponds. Many of the species here are rarely seen, but actually quite common: especially the Greater Siren (Siren lacertina.) Many people have never seen a siren before, and if they had they probably mistook it for an eel. But the Greater Siren is no eel – it is, in fact, a large Salamander.


Preying on smaller invertebrates, especially crayfish, these abundant salamander likely amount to a large force in aquatic food chains, though they can often be overlooked. They look similar to the less-abundant (in area’s I’ve searched, at least) Amphiuma, but can easily be distinguished by the presence of external gills. Interestingly enough, Sirens and Amphiumas make up the vast majority of the food for one of my favorite snakes: that Eastern Mudsnake.

Often overlooked by the casual herper, salamanders such as the Greater Siren are living proof that “There are more things in Heaven and Earth…Than are dreamt of in your philosophy.”




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Posted by on 05/07/2012 in Species Profiles


Species Profile: The Eastern Mudsnake (Farancia abacura abacura)

Like many hunters and watchers of all stripes, one of my favorite things to do is to “figure out,” a species. Now, I put that in quotes because the notion that you can completely figure out a species is kind of silly – the world of any species is full of surprises and aberrancies, and most species don’t read field guides to tell them where and when they should be. That said, one can still get really good at finding a species, and be very knowledgeable of their habits.

There’s one I’ve been working on lately: the Eastern Mudsnake (Farancia abacura abacura.) Now, you would think that having written about these critters in a field guide would be in my favor: despite this however, they seem to show up whenever they feel like it without any rhyme, reason, nor preference in aquatic habitat.

A (supposedly) strict Siren and Ampihuma eater, Mudsnakes are probably relatively restricted to areas where these aquatic salamanders are common. Unfortunately, this doesn’t eliminate too much habitat to find them: marsh, canals, sloughs, ditches, lakes, and any variety of aquatic habitat my house them, though they likely stay away from deeper, quicker moving streams and rivers – it is here where their congener the Rainbow Snake takes over.

My first Mudsnake allowed me a glimpse into this animal’s foraging habits: like many aquatic snakes, they aren’t a sit-and-wait type predator, but are a browser. My first Mud was in a culvert stream in Everglades National Park, swimming through the aquatic vegetation, poking its nose into various nooks and crannies, probing for a meal. Because of their overwhelming aquatic tendencies, Mudsnakes can somewhat overcome gravity and grow to a monstrous size and girth – the record for Mudsnakes in Georgia is 81.5 inches – almost 7 feet! Such an individual would have a girth on par with some of the fattest Eastern Diamondback Rattlesnakes (Crotalus adamanteus), but would surely not match the attitude – Mudsnakes are typically very placid, at most jabbing at unsuspecting handlers with their barbed tail. This barb is, consequently, harmless and painless.

Once again though, this is a species that I’m trying to figure out, and so far unsuccessfully: aquatic trapping and targeting certain habitats these past few months have failed to turn up any. I do have some comrades in my confoundedness though: Durso, et al in a recent paper, “Needles in haystacks: Estimating detection probability and occupancy of rare and cryptic snakes” found Mudsnakes equally hard to figure out – while difficult to find snakes such as Rainbow Snakes and Swamp Snakes could be linked to certain variables; Mudsnakes showed up wherever they pleased, whenever they pleased. Perhaps that is the secret: perhaps a snake as beautiful and cryptic as a Mudsnake do as they wish – nothing more.


Posted by on 01/05/2012 in Species Profiles