The Lizard Log

The Langkilde Lab in Action


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Winter Is Coming; Herp While You Can

Since my summer has been full of writing and conferences and decidedly empty of time spent working with reptiles and amphibians, I decided to take advantage of a recent family wedding (congrats Tanya!) and do some herping in North Carolina, a state I haven’t spent much time in since my undergraduate days in the Herpetology Lab at Davidson College.

Even before arrival at my final destination, I spotted a promising sign: a green anole (Anolis carolinensis) out basking in the afternoon sun near the Forest Service office.

Ancar

Ahhhh, sunlight.

I camped in the Uwharrie National Forest, a relatively small national forest with some nice campsites on Badin Lake.

Yep, pretty nice alright.

Yep, pretty nice alright.

While it’s been getting chilly here in State College, the climate in NC is still rather balmy with daytime temperatures in the 70’s and nighttime temps warm enough for a little reptile activity, at least on the roads. Unfortunately, warm roads with cars and cool weather are a pretty good recipe for snake deaths, and the first snake of the trip was a DOR (dead-on-road) scarlet kingsnake (Lampropeltis elapsoides). These gorgeous snakes are coral snake mimics and can be an unusual find.

Laela

DOR snakes often look a little bug-eyed…:*(

A full day of hiking around Badin Lake, and through streams and backwoods resulted in a decent turnout, including many of the usual suspects:

Licat

Bullfrogs (Lithobates catesbeiana) were common along the shoreline of the lake and in adjacent streams.

Cocon

The most surprising thing about finding this black racer (Coluber constrictor) was that it didn’t bite me….what?!?

Sclat

This little brown skink (Scincella lateralis), was moseying through the leaf litter in a sunny patch along the lakeshore. And yes, that is its “official” common name. Scientists are so creative!

Acgry

Northern cricket frogs (Acris crepitans) were abundant throughout the forest and easy to spot as they used their outrageously long jumps (> 3 ft for a frog <2 in!) to escape approaching humans (me).

Defus

Northern dusky salamanders (Desmognathus fuscus) were holding out in a small spring seep in an area surrounded by muddy creeks and lots of horse poop.

Psfer

Upland chorus frogs (Pseudacris feriarum) were active, but not chorusing, on a cloudy day.

 

Nerodia2

This hatchling midland water snake (Nerodia sipedon pleuralis) was none to pleased to be removed from its natal creek (and bit me numerous times, as watersnakes are wont to do).

Nerodia1

However, it calmed down (a bit) when return to its aquatic environs.

On the way back to PA, I couldn’t resist targeting one specific species, the Peaks of Otter salamander (Plethodon hubrichti). This species is found only along a 13 mile stretch of the Blue Ridge Parkway near Peaks of Otter (surprise!) in southern Virginia and is under review to be considered federally threatened or endangered due to its very limited range. This salamander is named after the eminent citizen naturalist Leslie Hubricht (who also discovered the Red Hills salamander) and was so named after a bit of scientific skullduggery (you can read the story here). Finding this species was no problem thanks to a tip on a great locality from ex-Langkilde Lab member Sean Graham. I’d found a few, snapped a couple of pics, and was on my way home in under 15 minutes.

Hubrichti

These ‘manders were all dirty from their stay under the local rocks, but, as I didn’t want to disturb the population too much, I settled for some slightly less polished photos.

And of course, I couldn’t resist stopping at some of the awesome overlooks scattered along the Parkway.

Fall

Even on a cloudy day, the fall colors were still very nice (even for a colorblind viewer!)

And with that, I’ll enter a long, dark winter of writing and working towards finishing my dissertation!

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Don’t Prey on Me: Part 2

Note: This is a follow up to my first blog on this project. For the background and an explanation of the study, see Part 1

By Mark Herr

The field season is heating up for my summer Timber Rattlesnake project! As described in the first post, we’re using foam models of rattlesnakes to measure how the risk of predation varies between the different summer basking sites used by gravid female rattlesnakes. This project is a sub-project of the main study being conducted by Chris Howey looking into the effects of prescribed fire on rattlesnake ecology in general, and for most of the summer up until now I’ve been assisting with that study while we’re waiting for the gravid female snakes to arrive at their summer gestation sites. Well, it seems that they’ve (finally!) arrived, and so this week Chris, Alex (another one of the field techs on the rattlesnake project), Tom Radzio, and I have been deploying models and initiating the first field phase of the study!

Here I am with a beautiful yellow phase female rattlesnake that we found down the mountain below one of our known gestation sites. If she’s gravid then hopefully she’ll head up to the top to bask!

Here I am with a beautiful yellow phase female rattlesnake that we found down the mountain below one of our known gestation sites. If she’s gravid then hopefully she’ll head up to the top to bask!

One of our black phase models deployed against the substrate. We take a photo of each model after we place it out in the field so that we can reference them when examining them for signs of predation at the end of the deployment.

One of our black phase models deployed against the substrate. We take a photo of each model after we place it out in the field so that we can reference them when examining them for signs of predation at the end of the deployment.

Tom Radzio is a graduate student who’s currently pursuing his PhD at Drexel University. He’s an old friend of Chris’, and was generous enough to (awesomely!) provide us with field time-lapse cameras that we can use to record the happenings on the gestation sites while we aren’t there! Tom has used these cameras in his research on Gopher Tortoises in Georgia, and they should be incredibly valuable for us in this project, as they’ll let us truly see what’s happened to the foam snake models while they’re deployed. We were previously planning on trying to decipher any potential predation attempts on the models by examining the imprints left in the foam (as has been done in other studies) but now we’ll be able to look at the footage and see for ourselves exactly what happened!

Tom and Chris (in the tree!) setting up one of the cameras at a gestation site.

Tom and Chris (in the tree!) setting up one of the cameras at a gestation site.

We’ll be leaving the cameras up for the rest of the summer, and hopefully we’ll be able to record not only what happens to the foam predation models, but also anything interesting that the actual snakes using these sites are doing during the day. We might be able to use this data to figure out when the snakes are emerging at the different sites and when they go back underground for the night. Questions like that will help us to explore the other side of this project: how do the thermal qualities of the sites differ from one another? Do snakes need to emerge at different times, or stay out longer, at some sites because they are thermally inferior? Hopefully the cameras will help with resolving some of those issues.

The final setup! You can see the two lower arrows pointing at two models, one black and one yellow. The top arrow shows one of the cameras that’ll record the site for later analysis.

The final setup! You can see the two lower arrows pointing at two models, one black and one yellow. The top arrow shows one of the cameras that’ll record the site for later analysis.

Of course, our primary tool for examining those questions will be the copper thermal models that we’ll be placing out at the gestation sites very soon -as early as this next week! They’ll go out after we retrieve the foam models from the sites at the end of this first deployment (which’ll be on Monday – we’re keeping the foam models out for one week at a time).

I’m excited that this project is finally in full swing, and hopefully we get some interesting results over the course of the summer! Also exciting is the fact that I received an SSAR Roger Conant Grant In Herpetology for this project! I had applied this winter during the semester and was anxiously waiting to hear back, and now we’ll be able to use this grant to assist with some of the costs associated with the cameras and models. I’m so happy to have received the grant, and I couldn’t have done it without Chris and Tracy who helped to devise the project!


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Everybody Likes Pretty Pictures

Since our research trips to the South consist of only one short excursion this summer (we need to publish all the data we have rather than running every awesome experiment we can think of!), I took a quick one week jaunt through Alabama and Georgia for some R&R. Whether walking the banks of the Chattahoochee or exploring trails along Mobile Bay, sampling homemade cheese at an out-of-the-way farm or eating some of the best fried chicken and corn nuggets I’ve ever had, I always found some time to catch and grab a few pics of some herps! I’ve posted a selection below to tide you over until the real research starts in a month or so:

S_undulatus_ground_intimida

This male fence lizard (Sceloporus undulatus) was not happy with me for intruding on his territory along a trail and puffed himself up in the hopes of intimidating me into leaving the area.

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We often find fence lizards with ectoparasites like mites and ticks. How many can you spot on this lizard? (Answer at the bottom of this post).

P_guttatus_Export

Rounding a bend in the road at 55 mph, I spotted this corn snake (Pantherophis guttatus) in the middle of my lane and quickly straddled him with my car before pulling over on the shoulder. After running back down the road on my own two feet, I snatched him for a quick pic before releasing him into the forest safely off to the side.

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I found this ground skink (Scincella lateralis) out foraging in the middle of the day at Kolomoki Mounds State Park in Georgia.

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Kolomoki Mounds was also awash in southeastern slimy salamanders (Plethodon grobmani), one of the prettiest slimy salamanders due to their extensive patterning.

O_aestivus_Stare_Export

This rough green snake (Opheodrys aestivus) appeared rather happy (well, they always look like they’re smiling) to meet me on a trail in Bon Secour NWR.

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I chanced upon this kingsnake (Lampropeltis getula) basking quietly in a half log and getting ready to shed.

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Six-lined racerunners (Aspidocelis sexlineata) don’t often sit still take have their pictures taken, but this one was a little more tractable than most so I snapped a quick portrait.

ScelopMiteArrow

For the sharp-eyed among you, there are >3 ectoparasites on this lizard. Mites and ticks tend to concentrate on places where they can get underneath or between a lizard’s scales to attach and feed; these place include areas around the eyes, ears, and pockets of skin on the neck (not very visible here). On just one side, this lizard has a swollen tick in his ear, a new tick on the front of his eye orbit, and a cluster of bright red mites on his upper eyelid. Life ain’t always easy when you’re a fence lizard.


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Redemption in the Deep South

This undergraduate guest blog post has been dispatched by Mark Herr, a junior from Los Angeles who is majoring in Wildlife and Fisheries Science at Penn State. Mark is a member of the Penn State Presidential Leadership Academy, and is interested in continuing on to graduate school to study behavior, ecology, and, of course, reptiles & amphibians:

This past spring I applied for, and with the help of Dr. Langkilde received, a Penn State Discovery Summer Grant to conduct independent research. Initially, I planned to conduct two projects on similar systems. Unfortunately, only the second project (hence the title of this post) resulted in a successful field season. Which isn’t to say that the first project wasn’t valuable – it was perhaps the most valuable research experience I’ve had yet – but its value really lay in lessons learned rather than any publishable results!

Before I explain the project, I want to first give a shout-out to Drs. Langkilde and Sean Graham. Dr. Langkilde managed to let me know that my initially proposed projects were all rather grandiose and unfeasible, while convincing me to keep on firing away with ideas. Eventually, I sent her an idea that we both agreed was novel, and more importantly, possible. Sean went out in the field with me during every day of sampling and made the project possible. This is all the more impressive because he is a post-doc researcher and I am just an undergraduate – which says much both about him and the atmosphere that Dr. Langkilde fosters in her lab.

Dr. Sean Graham does his best to become an internet sensation by displaying a cottonmouth using the standard forced perspective method so that it appears to be of monstrous size. However, this snake is actually only a little over 3 ft. long. The camera really does add a few pounds.

Dr. Sean Graham does his best to become an internet sensation by holding a cottonmouth safely out of striking range while using the standard forced perspective method so that it appears to be of monstrous size. However, this snake is actually only a little over 3 ft. long. The camera really does add a few pounds.

I don’t want to delve into the specifics of my project idea in California, both because it will bring back the stinging memory of defeat (just joking!) and poison oak rashes so bad that they probably warranted hospital visits – both for Sean and I! Luckily, Sean and Dr. Langkilde had foreseen the fact that all might not go as planned with one of the projects – and so they had suggested that we conduct a second project as insurance. And so it was this “insurance policy” that became my last true hope for some publishable research during the summer break.

My project ran side by side with other work being conducted in Alabama by the Langkilde Lab, which allowed me to help out with other projects when I wasn’t out in the field with Sean collecting snake blood. Yes. Snake blood, and no, this didn’t involve door-to-door salesmen selling cure-alls or primitive rituals by witch doctors.

Sean and I investigated how the stress hormone (corticosterone) concentrations in Cottonmouths (Agkistrodon piscivorus) were related to their anti-predator behavior. Cottonmouths are large bodied, aquatic pit vipers native to the southeastern US. Most importantly, they are abundant. The snakes were honestly even more abundant than I had expected – even though we did have a period where we had trouble finding any, but more on that later.

They are also famous for being aggressive, or, at least that is what the man on the street will say – the consensus among scientists and in peer-reviewed research is that they aren’t anything close to the bloodthirsty mankillers they are made out to be. Cottonmouths do, however, have an extensive suite of anti-predator behaviors. They vibrate their tails (even though they have no rattle), they hiss, they can strike, and they can open their mouth wide in what is called a ‘gape’ in order to convince a possible predator that they aren’t worth the trouble. Actually, this gaping behavior is what gives them their common name – the inside of their mouths has a white lining that is highly visible (especially in their often dark habitats).

A Cottonmouth from the Everglades showing the display for which it is named.

A Cottonmouth from the Everglades showing the display for which it is named.

The fact that this species has so many different anti-predator behaviors means that I was able to formulate a point system that would rank each individual snake based on how “defensive” it was acting. The procedure was to approach the snake and stand in close (but safe) proximity to it for 15 seconds and then grasp it mid-body with a set of snake tongs for another 15 seconds – all the while taking note of every behavior that the snake exhibited. We would then use a snake tube to restrain the animal and take a blood sample.

As I write this I am laughing out loud at how simple that last sentence makes the blood drawing seem.

The problem, as you might imagine, is that often times (read: every time) the already defensive snake wants nothing more than to avoid slithering up a tight clear plastic tube so that we might get our blood sample safely. For obvious safety reasons, the entire tubing maneuver has to be completed using nothing but a set of snake tongs and a tremendous amount of patience – tubing is the safest way to handle venomous snakes – by far (both for the snakes and the researcher). It’s the industry standard technique.

The process goes something like this:

  1. Using a pair of snake tongs, the snake is grasped firmly enough at the midbody to prevent the snake from escaping but not so tightly as to injure the animal.
  2. The tube is maneuvered such that it fits over the snake’s head, and ideally the snake will crawl up the tube such that its body is half inside and half outside the tube, with the snake’s posterior body portion and tail hanging out of the end.
  3. Swiftly and steadily, the snake is grasped at midbody at the exact point where it hangs out of the tube – with the hand holding the snake firmly grasping both the animal itself and the tube to prevent the snake from either moving further forward or backing out.

Step #2 is sometimes easy, as the snake will cooperate and crawl up the tube as soon as it is able. Usually, though, it is not so easy. More often it would rather keep dodging and moving its head away. Even more often it would rather just strike the tube repeatedly. This process was further complicated by the fact that we were on a tight time schedule –we needed to obtain blood from the snake before its hormone levels had risen significantly (which takes only a few minutes). Did I mention the fact that we were unable to physically touch the snakes until they were in the tube?

A safely and successfully tubed Cottonmouth on display after obtaining a blood sample.

A safely and successfully tubed Cottonmouth on display after obtaining a blood sample.

We went out during the day and at night searching for snakes, usually spending at least 4-5 hours at a stretch slogging through swamps in waist deep swamp water, and we managed to get to within about 5 snakes of our sample size when we hit a wall. No. More. Snakes.  I can’t even remember how many times Sean and I ventured forth without finding even a single snake. It was as though cottonmouths had gone from being the most common snake in the Conecuh National Forest to almost nonexistent. A change in the weather may have been the culprit, but I wasn’t nearly as concerned with the source of the problem as with the prospect that I might not find enough snakes to complete the research.

Luckily, we had a solution. Sean had a location that he knew would guarantee snakes en masse – unfortunately, it was too far away for just a day trip. Our solution was to hit this magical spot on the way back to Pennsylvania on our very last day.

I can’t tell you how nervous I was when we went out that final night.

To set the stage:

  1. We didn’t have enough snakes. More importantly, we really needed to find a specific subset of snakes, adult males, which are significantly more difficult to locate than adult females or juveniles.
  2. We absolutely had to leave for Penn State the next morning, making this the absolute last possible time to get enough snakes to complete the project.
  3. The previous four days hadn’t yielded even a single snake.
  4. Just for dramatic effect, there was an absolutely MASSIVE electrical storm just prior to our sojourn, shaking the ground and lighting up the sky like a child repeatedly turning the lights on and off inside an otherwise pitch black room.

Well, that night could have shared a title with this post: Redemption in the Deep South. After working from 8:00 pm to 2:00 am, slogging through waist deep (read: sometimes neck deep) blackwater while exhausting our drinkable water, getting lost, and receiving (conservatively, of course) 1,000,000 mosquito bites, we found our 5 snakes. Three of the five were adult males. Our goals were complete. Victory.

I am still in the process of inputting data and running samples, so I can’t yet tell you how stress hormone levels in cottonmouths relate to their behavior. What I can tell you is that working through the trials and tribulations of this summer’s research has made me a better scientist by far. I have many to thank for making this experience possible, but my highest gratitude extends to Tracy Langkilde, Sean Graham, and the cottonmouths of south Alabama. Thanks guys.

Adapted from Mark Herr’s Presidential Leadership Academy Blog