Tuesday, May 31, 2011

Herpin' In the Sandhills Part IV: A Pair of Awesome Constrictors.

Continuing my series of posts devoted to our herping trip to the Sandhills in April.  I've discussed the cottonmouths, the scarlet kingsnakes and the amphibians we encountered.  But, I still have some more incredible snakes to share with you all.

So, I'll contiue with a tale of two awesome constrictors.

The first of which was a huge treat for me.  Believe it or not, although this snake is not native to anywhere that I've lived prior to moving to the southeastern US, I've had alot of experience with this species in captivity.  It's one of the most commonly kept snakes by folks who are into herpetoculture (i.e., the keeping of amphibians and reptiles as pets).  I'd even had one as a pet for about 9 years.  One of the reasons I wanted to see one so badly was because it was hard for me to separate the domestically-bred pet from the wild animal.  Thus, it's hard to picture this snake outside of a terrarium.  So to find it out and about, just doing what wild snakes do, was sort of a geeky moment for me (perhaps equivalent to a Star Trek fan meeting Shatner, or something :) ).

The Corn Snake (Pantherophis = Elaphe guttata).  Jeff has a nice bit of property in the Sandhills.  Like every good Herpetologist should, he has littered his front and back yard with peices of tin.  The tin provides cover and warmth, which snakes like (especially on a cool April day).  So having alot of tin around to flip increases the chances of seeing something snakey.  Such was the means by which we captured TWO cornsnakes in about 25 minutes. 

Folks in the snake breeding business love to come up with ridiculous color morphs for these guys. 

That's cool and all....but in my mind, nothing beats just plain old cornsnake color.

Above: two pictures of the first individual we found under the tin.  A smaller, perhaps subadult, individual but very handsome!!

Above: the second and much larger individual we found under the tin.  We didn't want to disturb him, otherwise I suppose we could have gotten a picture of someone holding him for scale.  He was a nice size.

Notes on Corn Snake Diet:  Members of the Genus Pantherophis (previously Elaphe) are generally referred to as the "ratsnakes".  They get this name for obvious reasons (i.e., they like to feed on rats and other rodents).  The most thorough review of Corn Snake diet that I am aware of found that mammals make up 59% (by occurrence) of this species's diet, and 45% (by volume; Hamilton and Pollack, 1956).  But, Corn Snakes will also eat birds, bird eggs, lizards, other snakes, frogs, etc.  Regardless, the preference for mammals, like rodents, makes the Cornsnake a species that is beneficial to have around.

The Northern Pine Snake (Pituophis melanoleucus melanoleucus): this is a critter very near and dear to my heart.  I'd spent three years radio-tracking the habitat selection and movement patterns of another member of this Genus (the Bullsnake, Pituophis catenifer sayi) in Wisconsin.  So gettting to handle a Pine Snake was like catching up with an old friend that I hadn't seen in awhile.

This species is relatively uncommon in North Carolina. We were fortunate with the individual pictured below.  Ed had found him the day before crossing a rarely travelled dirt road and put him in a bag for Jeff.  Jeff is currently involved in research on this species, but their general rarity makes them hard to find (it should be noted here that both of these folks have the appropriate state permits to do this sort of thing).  Dave and I were able to come with when the animal was released back at its capture location. 

Much like the Cornsnake, the Pine Snake is basically restricted to the fire-dependent habitats in the Sandhills region.  Many species within this genus prefer sandy soils and are actually very adept at burrowing, whether to create a refugia, a nest, or to find prey.  In fact, it has been estimated that the Bullsnake can move up to 207.5 cubic inches of soil per hour (Carpenter 1982)!  Not bad for something with no arms and legs.  The activity of digging is actually accomplished with a pointed & hardened rostral (nose) scale and powerful body undulations (see picture below).

Above: example of the habitat that northern Pine Snakes may be found in.

Only a handful of published research projects have been conducted on P. melanoleucus.  This includes a few studies on snakes in New Jeresy (USA; Burger and Zappalorti 1988, Burger et al. 1988), some in Tennessee (Gerald et al. 2006a, Gerald et al. 2006b), one in Mississippi (Baxley and Qualls 2009), and one in Florida (Franz 2005).  Currently, the best state-specific source for information on them is Palmer and Braswell (1995).  There is a real need for further published research on this species to help gain a better understanding of its ecology. 

As an aside, with the exception of the Indigo Snake (Drymarchon corais), members of the Genus Pituophis are the largest snakes north of Mexico.  Adults often grow larger than 5 ft, perhaps getting to 6 ft.  I have recieved anecdotal reports of 8 ft Bullsnakes in Wisconsin, which I have never substantiated (the largest individual I ever encountered was over 5.5 ft).

Above: a close-up of the head.  Note the thick rostral (nose) scale at the tip of the snout.  This is found in all members of the Genus Pituophis, and functions to aid these snakes in digging.

I've got a few more posts related to our trip, which I'll get to soon.

Literature Cited:

Baxley, D.L. and C.P. Qualls. 2009. Black Pine Snake (Pituophis melanoleucus lodingi): spatial ecology and associations between habitat use and prey dynamics. Journal of Herpetology 43:284-293.

Burger, J., and R.T. Zappalorti. 1988. Habitat use in free-ranging pine snakes, Pituophis melanoleucus, in New Jersey Pine Barrens. Herpetologica 44:48-55.

Burger, J., R.T. Zappalorti, M. Gochfield, W.I. Boarman, M. Caffrey, V. Doig, S.D. Garber, B. Lauro, M. Mikovsky, C. Safina, and J. Salvia. 1988. Hibernacula and summer den sites of pine snakes (Pituophis melanoleucus) in the New Jersey pine barrens. Journal of Herpetology 22:425-433.

Carpenter, C.C. 1982.  The bullsnake as an excavator. Journal of Herpetology 16:394-401.

Franz, R.D. 2005. Up close and personal: a glimpse into the life of the Florida Pine Snake in a north Florida sand hill. In Amphibians and Reptiles: status and conservation in Florida. W.E. Meshaka, Jr., and K.J. Babbitt (eds.). Krieger Publishing Company.

Gerald, G.W., M.A. Bailey, and J.N. Holmes. 2006a. Habitat utilization of Pituophis melanoleucus melanoleucus (northern pinesnakes) on Arnold Air Force Base in middle Tennessee. Southeastern Naturalist 5:253-264.

Gerald, G.W., M.A. Bailey, and J.N. Holmes. 2006b. Movements and activity range sizes of northern pinesnakes (Pituophis melanoleucus melanoleucus) in middle Tennessee. Journal of Herpetology 40:503-510.

Hamilton, W. J., Jr.  and J. A. Pollack. 1955. The food of some colubrid snakes from Fort Benning, Georgia.  Ecology 37:519-526.

Palmer, W.M., and A.L. Braswell. 1995. Reptiles of North Carolina. University of North Carolina Press.

Sunday, May 29, 2011

Wary Coyote

I wanted to title this post "War E. Coyote"...a delicious pun on the full name of the well-known Loony Tunes character.  Unfortunately...no matter how I tried to tweak it...the blog post title kept coming off like a coyote that wanted to go to war.

So I gave up.

Anyhoo, the camera at my Otter Latrine set caught another example of coyote aversion to the red LEDs of an infrared camera trap.  On April 13, a 'yote comes past from behind the camera.  This is the direction most of them are heading when I get pictures of them at this camera trap set.  What this means is that they probably don't notice the red glow from the infrared LEDs. 

If they are looking at the camera, they'll see the red glow.  As I've reported elsewhere, 'yotes seem to show alot of aversion to this red glow (although they apparently acclimate, see Coyote Cams posted on February Feb. 19th, 2011). 

The individual (or an individual) comes back alittle while later, but is facing into the camera.  I think this might be a different 'yote actually, as it appears alittle smaller than the first (although this could just be the camera angle).

Everything seems fine and then....you can almost hear the comedic exaggerated automobile braking noise.
Above: Whoa!  What the hell is that?!

And then he's gone.  No 'yotes have passed by this camera since.

Friday, May 27, 2011

Week's End Survey Round-Up: Snakes, Salamanders, and Mice (and toads), oh my!

Although we caught more than what I'm going to show...these were some of the week's highlights from our drift fence and coverboard surveys.

The Northern Watersnake (Nerodia sipedon): This very common species can occur in just about any lowland habitat in our region (swamps, ponds, marshes, streams, rivers, resevoirs, etc.).  Although it's always a treat to catch them, it's not neccessarily unusual.....except the circumstances under which we captured this individual.  We usually throw funnel traps into ephemeral wooded wetlands at the study sites to catch amphibian larvae.  These funnel traps have been chalk-full of salamanders larvae lately (Ambystoma maculatum larvae).  This juvenile watersnake was captured inside one of those funnel traps in the wetland, which shocked the heck out of me when I pulled it out of the water.  He was probably taking advantage of a captured food source....but I guess he couldn't figure out how to get himself back out! 

Note the vaguely triangular-shaped head that occurs when the animal is threatened....this superficially resembles a venomous snake.   Unfortunately for the watersnake, its penchant to be alittle nippy and the tendency to flatten its head when threatened reminds folks of a venomous snake (often a Cottonmouth).  Thus, the harmless watersnake is often treated as harshly as venomous species are.

Fowler's Toad (Bufo fowleri) is a species that I had no experience with prior to moving down south.  The individual pictured below was hopping along the trail as we walked into the site earlier this week.  They are superficially similar to the American Toad (Bufo americanus), which is also common in this region.  Interestingly, though...at this particular site almost all of the toads I find are Fowler's, not Amercan Toads.  Not sure why.  The habitat is good for both.  I can't imagine they competitively exclude eachother.

The Fowler's can be distinguished from the American in several ways.  First, is the number of tubercules (or "warts", or bumps) inside of the dark circles on their backs.  If any of the dark circles have 3 or more large tubercules, then you probably have a Fowler's Toad (the American Toad has only 1 or 2 tubercules in each circle).

Also, the Fowler's has relatively small tubercules (or "warts" or bumps) on their legs, as below.  In contrast the American toad has large tubercules in this region.

For comparison, see two examples of American Toads that I captured at a different site last year.   Note the 1-2 tubercules in the dark circles on the back.

Juvenile White-Spotted Slimy Salamanders (Plethodon cylindraceus) were very common under the woodland coverboards at one of the sites this week.  I've posted about capturing them in the past too (see A Good Day for Herps posted on March 23, 2011).

The Spring Peeper (Pseudacris crucifer) is a relatively common species, but one that hadn't been detected at this site until this week.  Last year, I found them at the other site nearby.  The individual below was captured while searching for box turtles in a lowland deciduous forest.  This species can exist in very high densities back home in Wisconsin and I am used to finding hundreds of them in the spring.  This does not seem to be the case in my experience here in the southeast to-date.

As an aside, the specific latin name of crucifer refers to the "X"-shaped mark on their back (second picture below).

The Eastern Harvest Mouse (Reithrodontomys humulis) is not the most common rodent species we encounter at our sites.  Usually, that is reserved for the White-Footed Mouse (Peromyscus leucopus), which we catch frequently in drift fences, under coverboards and in Sherman Traps.  Every so often, however, we get alittle Harvest Mouse.  The individual below was captured in a pitfall trap of one of the grassland drift fences we're running. 

Some general rules for distinguishing them from the white-footed (aside from the obvious fact that white-footed mice tend to have lighter, more whitish feet):  the ears aren't (proportionally) as large in the Harvest Mouse as in the White-Footed Mouse.  Also, the light fur on the underbelly of the White-Footed is more clearly delineated and comes higher up onto the sides than on the Harvest.  Finally, they can be distinguished by habitat.  While the White-Footed is most often encountered in woodlands, the Harvest Mouse is more common in grasslands, old fields and field edges.

For comparison, here are two pictures of White-footed Mice captured in a drift fence (top) and a Sherman Trap (bottom) earlier this year. 

The Southern Two-Lined Salamander (Eurycea cirrigera) pictured below was a first-time capture at this site.  We'd found them in relatively high numbers at our other study site...but hadn't gotten them at this one yet.  Another lungless salamander of the family Plethodontidae, this rather delicate little critter is more often encountered near streams. In fact, the way we find them at our other site is by flipping flat rocks along a stream edge.  This fella was captured in our upland forest drift fence, which borders a rather dry pine stand.  Not where I expected to catch him.

More to survey info will be posted in the coming weeks, I hope.

Have a good weekend!

Wednesday, May 25, 2011

Baby Whistle Pigs

The first shot of some baby Whistle Pigs (Marmota monax) at this camera trap set.  Four of 'em, it appears.

According to a variety of sources summarized by Feldhammer et al. (2003), average litter size for this species hovers right around 4 to 5 individuals.
  • Litter size of 4.8 (sample of five females) in Ontario.
  • Litter size of 4.5 (sample of four) in Illinois
  • Litter size of 4.3 (sample of seven) in New York.
At 33 days old, young emerge from the nest for the first time and they wean at 42 days (Ferron and Oullet, 1991).  After one week of age, mother-infant contact begins to decline, which culminates in no contact at the time of weaning (Barash 1974).

Breeding usually occurs immediately after emerging from hibernation.  Young are born after a gestation period of 28-33 days (reviewed by Feldhammer et al. 2003).

The litter size pictured above is within the norm.  Also, these little Whistlers were probably born in late April (around the 20th, or so), as a result of adult copulation in late March.  The first adult pig captured active and above ground on this camera was on March 7th...so copulation occurring shortly after this makes sense, given the timeline I've just laid out.

Regardless of all that, those babies are pretty cute.

Lots going on this time of year, and lots more to report!  Trying not to fall behind!  More to come soon.....

Literature Cited:

Barash, D.P. 1974. Mother-infant relations in captive woodchucks (Marmota monax). Animal Behavior 22:446-48.

Feldhammer, G.A., B.C. Thompson, and J.A. Chapman. 2003. Wild Mammals of North America: biology management and conservation (second edition). The Johns Hopkins University Press.

Ferron, J. and J. P. Ouellet. 1991. Physical and behavioral postnatal development of woodchucks (Marmota monax).  Canadian Journal of Zoology 69:1040-1047.

Tuesday, May 24, 2011

First Fawn of the Year.

Today marked the first observed fawn of the season.

Dave and I were out tracking radio-tagged box turtles when I saw it. 

I could tell by the "beep" on the telemetry reciever, that I was getting close to the turtle.  When that happens, one tends to get tunnel-vision (focused only on what's immediately at one's feet, to avoid accidentally stepping on the turtle).  No more than five feet to my right, I heard a small commotion and looked to see a very young fawn jump up and run off into the woods.

I've gotten within 2-3 feet of fawns in the past (also while tracking herps with radio telemetry equipment), but these were in Wisconsin.  I didn't realize that the batteries on my camera were dead when I took it into the field today, and it wouldn't have mattered because the fawn was up and running before I had known it was there.  Regardless, I didn't get good pictures.

But, below are a few pictures of the last young fawn I ran into in the woods.  This was from 2005 and this individual wouldn't budge until I got into almost an arm's length of it (hence the nice photos). 

The date on the pictures from the day of upload were (surprise) May 24th, 2005. 

Exactly 6 years ago today!

Sunday, May 22, 2011


Photo courtesy of M. Forsberg.

Checked the drift fences with two of my students on Friday, May 13th.

We were all excited to find a Copperhead (Agkistrodon contortix) in one of the funnel traps.

The individual was a sub-adult female.

In our neck of the woods, it's a relatively common species and may even end up in suburban/urban areas. 

As a venomous snake, Copperheads are often treated harshly by humans.  Even by folks that claim to like "wildlife".  I can understand the fear venomous critters promote and, as a father, I can understand the concern folks have about them in suburban/urban landscapes.  I wish there was a good solution for this problem....but there doesn't seem to be.  This is mostly due to the fact that there's not many places to go in the eastern US if you're a snake that aren't frequented by...or at least visted by.....people. 

This means there is lots of potential for interaction between humans and things that may accidentally do humans harm.  I say 'accidentally' because, let's face it, venomous snakes don't seek out humans to bite.  Bites occur when the snake is threatened.  Unfortunately, the snake may feel threatened even if you don't know it's there.  The Copperhead blends in so well, that it's not suprising folks unknowingly step on them, or place their hands near them. 

But, to put this in perspective, I've spent literally hundreds of hours at my study sites near campus, which are confirmed Copperhead locations.  These sites are comprised mostly of good Copperhead habitat (better habitat than found in many urban/suburban backyards).  Despite this, I have yet to just walk up on one in the field, and all of the individuals I've seen were captured in drift fences.  I imagine I've walked by oodles of them without knowing.

Regardless, dealing with a Copperhead in your backyard is a much different issue than killing a Copperhead that you happen to come upon while hiking in the woods.

But, I'm a strange person and I empathize with the critters that folks fear or dislike.  Especially the critters that, despite being loathed by humanity, are able to hang on. 

Regardless....if one can separate themselves from the fact that it's a venomous snake, its an incredibly handsome critter.

Photo courtesy of M. Forsberg

Thursday, May 19, 2011

The Right-of-Way Wanderers.

The Cuddeback is one of my "rover" cameras.  I move it around every few months at this site trying to find interesting stuff.  My Bushnells are the workhorse "fixed" cameras that remain in one place at my sites (hopefully for a year per location).

On September 23th, 2010 I moved my Cuddeback to a location along a transmission line Right-of-Way (ROW).  This ROW runs through the study site, and cuts a large tract of relatively undisturbed deciduous hardwood forest in two.  In the process, it crosses a stream and runs into an open pasture nearby.  The ROW therefore creates an easy travel corridor through the woodland, while also crossing a water source, before emptying into an open field.  I had high hopes for carnivores, particularly Bobcat (Lynx rufus). 

So, I decided to check out the ROW for a camera location in late September, 2010. Although ROWs have upsides, they have downsides: namely, its hard to conceal a camera when mounting it along a ROW through public property that may be frequented by hikers and powerline employees.  As such I couldn't put it right on the edge of the woods facing into the ROW, which is what I wanted to do.  I had to put it slightly back into the woods.  Because I was going to use some scent lures and bait, I also made sure I focused on hilltops when scoping out camera set locations....I wanted the wind to get that scent out from up on that hill.

I came across a wildlife trail running perpindicular to the ROW from the woods.  It was up on a hill in between the open pasture to the southeast and the stream crossing to the northwest.  It seemed like it had what I envisioned. 

Above: an aerial photo of the region with an outline of the study area.  Note the ROW transmission line bisecting the property that is clearly visible.

So, I drug an old stump (probably from some ROW clearing) in front of the camera.  I dug a small hole at the base of the stump for bait.  It was my plan to use the stump for the scent lures and coyote urine spray, while putting potential bait in the hole (trying to simulate the classic "dirt hole" set that traditional trappers use).

Basically, though, for two months this spot yielded deer.

....nothing but deer.

Oh, and a few squirrels......

Even the occassional construction vehicle, moving along the Right-of-Way to perform maintenance.

I was beginning to think this was a dud camera set. 

Then...after two months...things started to get interesting.  I had been placing scent lures in front of the camera for weeks.  A dab of commercial coyote gland lure one week, the next week gray fox gland lure...every time finishing it off with a spray or two of coyote urine.  A squirrel carcass once.  The unused turkey neck from our Thanksgiving dinner another time.  One week, I finally went through the trouble to drag a few nuggets of excrement from my faithful pooch out to the camera and set it there.

That seemed to finally do the trick.

At last, a carnivore....the Gray Fox (Urocyon cinereoargenteus)....who takes a minute to mark on top of my dog's excrement.

...a few days later, another fox investigates the handiwork.....

....a pair of Gray Fox investigate on December 13th....


Around December 15, 2010 I upped the ante.  I picked up the ribs/spine of a roadkilled deer off of a side-road that I'd been watching.  The county hadn't come to pick it up for weeks.  It was mostly picked clean, but still juicy and with plenty of meat on the bone.  I hauled this out to the spot and wired it to a stake in front of the camera.

The first visitors were a pair of 'possums (Dildelphis virginiana), a common scavenger 'round these parts.....

A Barred Owl (Strix varia) also stopped by (more on this later).......

...as did another Gray......

A 'possum AND a white-tailed deer....

A hawk...based on its relative commoness in the area, I'm going to guess Red-Shouldered Hawk (Buteo lineatus), but that's just a guess.

In December I caught something that is amazingly rare in the southeast: SNOW!

The one and only Racoon (Procyon lotor) captured on this camera.  Had I put this deer rib cage out in a setting closer to water....'coons would have raided it on the first night.  As it was, I only got this big old ridge runnin' raccoon to stop off for a gnaw.

A very nice Gray Fox shot in the early parts of the new year (sniffing about where I had sprayed the 'yote urine on the log)........

A deer in mid-leap....

More 'possums.....

Finally, a Gray Fox slinks past the set, but must not stick around long for this is the only picture of him on this night.

And even though I was reluctant to move the camera (I don't know why), a picture in the last batch that I looked through changed my mind.

Look close.  It's exactly what one never wants to see on their camera trap: a picture of some dude possibly checking it out from the seat of his vehicle.

So, the camera had to get moved.