Herpin' In the Sandhills Part VI: Whip-cracking!

There are a few snake species found here in the Southeastern US that I desperately wanted to see after moving here a coupla years ago.  I've been lucky enough to see a few of them already, several during the previous posts about our trip to the sandhills (see past posts on Cottonmouths, Scarlet Kingsnakes, a variety of amphibians,  some awesome constrictors, and a few cool odds-n-ends).

The reason I saved my account of finding this species for last is because I think it's my favorite.  I don't really know why.....but aside from the Eastern Kingsnake (Lampropeltis getula), the Eastern Diamondback Rattler (Crotalus adamanteus) and the Coral Snake (Micrurus fulvius), I've wanted to see a Coachwhip (Masticophis = Coluber flagellum) very badly!

I'd found one of my four most-saught after species early in the season last year.  Two of the species in that list have eluded me (as they are rare in our state), but I finally was able to find the fourth snake on that list during our trip to the sandhills in April.

Above: the habitat where the first Coachwhip was found.

There's just something about the common name for this species that always sounded cool to me.  It's different than many common names applied to species of wildlife, which are often just the most obvious and basic description of their appearance.

Five-lined Skink.

Bluebird

Short-tailed Shrew

Red-winged Blackbird

Two-lined Salamander

White-footed Mouse

BORING!

How about this:  COACHWHIP! 

Sort of descriptive...because the animal does, in fact, look like a bullwhip...or some kind of whip that carriage drivers would have carried.  But it is so much cooler than some basic descrptive name that could have been applied to this species like Brown-Tailed Black Snake....or something equally as lame.

The name even sounds tough....like it could beat you up and steal your lunch money:  COACHWHIP!  (and, yes, it does help when it's written in all caps).

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We found two Coachwhips during our trip.  The first was a juvenile individual that the students in the herp class we were tagging along with found.  A very cool little specimen (and my first wild Coachwhip).  But, as I mentioned regarding the Cottonmouths....it's neat when someone finds them and you see them...but it's cooler still when you find them yourself.

How fortunate we were that Jeff knew the Sandhills area so well.  We visited a spot that he knew about where peices of tin had been scattered around, and started flipping.  Normally a sure-fire way to catch snakes.  However, it had been cool and alittle rainy during our trip and we were alittle nervous stuff wouldn't show. 

Luckily, our worries were unwarranted!

After the second or third piece of tin....success!  A huge adult Coachwhip.  And a very beautiful one, at that.  Check out that jet-black head and those nice rings leading to the beautifully patterned tail (see the close-up shot of the tail pattern in the pictures below).

Check out how big this guy was!  Almost six foot tip to tip. 

Look at the incredible scale/color pattern on the tail (below).  Stunning! 

You can also get a feeling for how long the tail is in this picture.  The "vent" (or area where the snakes goes to the bathroom out of, near my right pinky) is visible in this picture.  Basically a snake's tail starts at the vent.....



He was also pretty easy to handle due to the cool weather, which I'm told is not typical for this snake.  Jeff and Ed recounted stories of folks they know getting tagged by Coachwhips....apparently they have an penchant for nailing over-enthusiastic Herp-nuts in the face!

The cool weather also worked in our favor for picture taking.  This is normally a pretty jittery species.  Although previously placed within the Genus Masticophis, it is currently in the Genus Coluber....which also includes a species we encounter around our study areas alot:  the quick-moving Racer (Coluber constrictor).  Coachwhips are definately fast.  They've been clocked at maximum speed of 3.73 miles/hr (6.01 km/hr) by Mosauer (1935)!!  Not bad for a critter with no arms and legs. 

A snake moving that fast through scrub and brush is basically gone before the person trying to catch them even realizes what they've seen.  So for us to be able to catch and photograph them was incredible.

So, much like Racers, Coachwhips are sleek and fleet predators that use their speed to actively forage and chase down food.  I like to think of them as a "run-n-gun" type forager :).  In addition to that maximum speed of nearly 4 mph that I mentioned before, they have been clocked to prowl normally at a speed of roughly 0.3 mph (Mosauer 1935). While hunting, they are known to crawl with their head and neck off of the ground (Cooper et al, 1990), but will lower their heads and barrel forward when prey is detected. 

They eat just about anything, including many of the lightning fast little lizard species found in their habitats: racerunners (Cnemidophorus sp.), fence lizards (Sceloperus sp.) and skinks (Plestiodon sp.).  Mammals, birds and other snakes are also consumed.  Work by Hamilton and Pollock (1956) found reported the following food items in the stomachs of 45 Coachwhips analyzed: Lizards (68.9%), mammals (17.8%), snakes (8.9%), insects (8.9%), birds (2.2%); and turtles (2.2%).

According to Ernst and Ernst (2003) there is an interesting folk tale associated with Coachwhips.  This states that if pestered by a human, a Coachwhip will quickly grab the leg of the hapless homonid with the front part of its body and lash them with the long, thin ends of their tails. 

Believe it or not (and I was shocked by this), such claims are completely untrue!  ;)

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And with that, I finally conclude my series of posts about our herpin' trip to the Sandhills in spring of 2011.  It was a great trip and I've got to thank Jeff and Ed for taking time out of their weekends to show us around, not for any real scientific purpose...but just to have some fun.

We all need to have alittle fun now and then, don't we?

Thanks for a great trip, guys!!

Literature Cited:

Cooper, W.E., Jr., D.G. Buth and L.J. Vitt. 1990. Prey odor discrimination by ingestively naive coachwhip snakes (Masticophis flagellum). Chemoecology 1:86-91.

Ernst, C.H., and E.M. Ernst. 2003.  Snakes of the United States and Canada.  Smithonian Press.

Hamilton, W.J., Jr., and J.A. Pollock. 1956. The food of some colubrid snakes from Fort Benning, Georgia. Ecology 37:519-526.

Mosauer, W. 1935. How fast can snakes travel?  Copeia 1935:6-9.

A Mystery No More!

The case of the mystery animal has been solved (see The Mystery, posted Feb. 23, 2011)!
Earlier this month we got the picture below. 

Not a very clear shot, but still....had to be a mink.

Also, at about 7:30 am on the morning of May 30th, Dave and I walked down to the main part of the largish river that borders one of our study sites (not far from where our camera was stolen recently...grrrr).  We were setting a turtle trap for the week, and in the process of lugging the equipment down to the water line.  The banks there are steep and the County Park and Rec. department has actually installed a set of metal stairs for folks to walk down and launch canoes.  We reached the bottom of the stairs and I happened to glance across the river just at the right time.

"Hey, look!  There's a mink!"

On the opposite bank we saw the little mustelid bound along some rocks that lined the shore.  Then, it ran up the mud bank into some shrubby vegetation.  After a second or two it came back down to the water's edge and bounded upstream until we lost sight of it.  A quick glance at the muddy banks on our side of the river also revealed mink tracks.  So, either it was the same individual, or a number of them had been out and about. 

Always cool to see them in-situ and in real time!

This is only the third live mink I've seen in person. 

The first was a very young juvenile (with its eyes still closed) that was crying at a burrow entrance along the banks of a wetland that I was doing amphibian surveys in.  This was a while ago...back in spring of 2001, I think, in Houston County, Minnesota.  I never saw the parent. 

The second was an adult that I saw bounding along the gravel shoulder of a county road that ran parallel to a little stream.  This was Jefferson County, Wisconsin.  Probably 2007, if memory serves me....

But finally we got a picture that I'm comfortable calling a mink.  The pics of this critter came few and far between in recent months.  From February 9th through the 20th, one of these passed the camera on 5 different occassions.  Since then, there's been only two pictures, including the two associated with this post.

The picture above represents the last (and best) Mink picture we've gotten on-site in a year of camera trapping there.

Not the nice Mink picture I was hoping for, but still a Mink.  I even put out shellfish oil as a lure for two weeks, hoping it would come up and smile for the camera, but only raccoons paid any attention to it.  The water levels have gotten very low this month and I think it's just become too much work for Minks to climb up the bank at this location now.

So...finally....I pulled the camera.  It had been at this spot for over five months.  It's given me about everything I need from that particular location, I think.  Today, in fact, the Cuddeback got relocated to a brand-spanking new set location for another important purpose. 

Hopefully, it will be successful, and I'll share cool results with you in the future.

If not...well...such is the fate of most camera trapping endeavors.  ;)

Notes on the Ecology of Mink:

The Mink (Neovison vison, previously Mustela vison) has an elongated tubular body, with small ears.  The fur is fairly luxurious (the reason it is often farmed for clothing) and dark brown.  The Tail is sometimes darker brown or black and there is a white spot on the chin and chest.  It is found throughout much of the U.S. and Canada....with the exception of hot and dry locations in the southwestern US.  It has also been introduced, or escaped farming operations, to become established in numerous parts of Europe (reviewed by Lariviere, 1999).

Reproduction-. Much like another member of the family Mustelidae that I recently posted about (the Otter), the mink is an induced ovulator that can undergo delayed implantation (Hansson 1947).  Most mating occurs in March, and parturitioni occurs in late June (which coincides with the DOR individual with enlarged nipples that we found last week). 

Habitat and Diet-.  This species is almost always associated with aquatic habitats and they are not particularly picky about what type, it seems.  I've observed them in wetlands, along large rivers and also associated with small order streams.  They often take occupancy of old muskrat dens with multiple entrances that are close to water (reviewed by Lariviere 1999). 

The Mink is a carnivore.   It will consume a wide variety of foods, such as aquatic invertebrates, fish, amphibians, reptiles, birds and mammals (such as muskrats; reviewed by Lariviere 1999).  The main components of the diet often depend on what the locally available prey is (Ben-David et al. 1997).  They can be a primary predator of waterfowl and their eggs.  This species is not particularly adept at hunting in open water, and usually does its aquatic hunting from shore.  This it accomplished by located prey from above the surface of the water, or by focusing their efforts on prey in their refuges (Poole and Dunstone, 1976).

Avoiding Competition-.  It would seem that perhaps the mink and the otter could be direct competitors, as they are both aquatic mammals, with overlapping geographic ranges and similar diets.  Interestingly, where these two species are sympatric (i.e. found together) they often reduce competitive tension through resource partitioning in regards to habitat and diet (Ben-David et al. 1996).  Comparatively, the River Otter (Lontra canadensis) consumes more invertebrates (like crayfish) and fish than the Mink.  The mink then focuses more on mammals and birds....while also being found in slightly drier habitats and having a greater propensity to forage on-land compared to the River Otter (Gilbert and Nancekivel, 1982; Humphrey and Zinn, 1982).

Literature Cited:

Ben-David, M., R.T. Bowyer, and J.B. Faro. 1996. Niche separation by mink and river otters: coexistence in a marine environment. Oikos 75:41-48.

Ben-David, M., T.A. Hanley, D.R. Klein, and D.M. Schell. 1997. Seasonal changes in diets of coast and riverine mink: the role of spawning Pacific salmon.  Canadian Journal of Zoology 75:803-811.

Gilbert, F.F., and E.G. Nancekivel. 1982. Food habits of mink (Mustela vison) and otter (Lutra canadensis) in northeastern Alberta. Canadian Journal of Zoology 60:1282-1288.

Hansson, A. 1947. The physiology of reproduction in mink (Mustela vison, Schreb) with special reference
to delayed implantation. Acta Zoologica 28:1-136.

Humphrey, S.R. and T.L. Zinn. 1982. Seasonal habitat use by river otters and Everglads mink in Florida. The Journal of Wildlife Management 46:375-381.

Laviriere, S. 1999.  Mustela vison.  Mammalian Species 608:1-9.  Published by the American Society of Mammalogists.

Poole, T.B. and N. Dunstone. 1976. Underwater predatory behaviour of the American mink (Mustela vison). Journal of Zoology 178:395-412.

Week's End Survey Round Up V: The Copperhead, the Peeper of Spring, and the Misfortuned Furbearers

Well, despite the theft of our survey equipment, this week wasn't all bad!

Let me start with another bit of scenery.

Surprinsingly, the location above resulted in another interesting scenic photograph (see last week's post). 

This one, however, is interesting because of the pronounced rays of light coming from the upper right.  I also find it interesting because if one compares this picture to the one taken at the same location only a week ago, you can get a feeling for how much variation there is in the appearance of photos on these cameras.

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The Juvenile Copperhead (Agkistrodon contortix).  We captured this little guy in one of our grassland drift fences.  He was in a funnel trap.  This is the fourth Copperhead captured in this particular drift fence since last August.  So, not very common.  I've posted about finding Copperheads before, and catching a venomous snake never really looses its thrill.  Plus, these snakes are gorgeous!  Juveniles have an additional dimension to their beauty: the tail   The tails of juvenile copperheads are a bright yellow-white (see below).

This is because juvenile Copperheads hunt using a strategy called caudal luring. Copperheads are ambush predators, so they sit in one spot and wait for prey to come by.....then they strike.  Juvenile Copperheads increase their chances of ambushing prey with the aid of caudal luring.  This is accomplished by moving their yellow-white tail-tip in a serpentine fashion so that it resembles a worm....or some other bit of prey.  This tail movement then attracts frogs and lizards (which are a staple food item for young Copperheads).  Once the frog or lizard is close enough, the baby Copperhead strikes.

For a great document that summarizes and investigates information on the ecology of the Copperhead, see Fitch (1960).

Above: the juvenile Copperhead captured in our drift fence this week.  Note the yellow-white tail tip.

Above: a nice head shot of the little Copperhead.  I'll say it again, they are a handsome-looking snake!

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The metamorphosed Spring Peeper (Pseudacris crucifer):  It's the time of year when the amphibians species who laid eggs in the early spring are now having larvae metamorphose into tiny juveniles.  This week, for the first time, we started seeing froglets and tiny terrestrial salamanders.

One example was this tiny Spring Peeper froglet that I captured while tracking Box Turtles with radio telemetry equipment.  I happened to look down just as the little critter hopped out of my way.  It took alittle effort to catch such a minute (and delicate) amphibian while not injuring it, but I managed.

These frogs are some of the earliest breeders in the state, along with the Upland Chorus Frog (Pseudacris feriarum).  I heard both species calling in the ephemeral wetlands on-site as early as February of this year.  This is only the second individual of this species that we've captured at this site.  The individual captured previously was an adult....so click on the link to see the difference in size from the juvenile pictured below.

Above: newly metamorphosed frogs are usually small, but they are even smaller for members of the Genus Pseudacris.  These frogs are diminutive as adults, and as juveniles....well you can see the size compared to my thumb in this picture.

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The D.O.R. Mink (Neovison vison).  A Dead-On-Road, or DOR, animal is something one never wants to come across.  It really puts a downer on the day.  So...if I'm not at risk of putting myself or others in danger...I try and at least get something useful out of the carcass.  I don't have the facilities to make mammals into suitable museum specimens, but if it is an uncommon species and the carcass is still in good shape...I try to at least snap photos, get location information, note associated habitat, and take some measurements.  I then send this to the appropriate regulatory and/or museum folks.

For herps....it's alittle easier (no skinning involved, you just need access to a chemical fixative and preservative and some jars).  I always try to make specimens out of the DOR herps I find, if possible.

Anyways, we saw this poor mink dead in the middle of the road as we drove to the sites this Monday.  It was killed near a stream-crossing....with a fairly dense wooded riparian (i.e., stream-associated) buffer.  The carcass was fresh and in good shape.  We got some photos of the feet, head and etc..

Also turns out, it was a female with enlarged nipples, which meant that she was nursing young nearby.  Those young may not have very good odds of survival anymore.

While taking pictures, I attempted to snap some of the critters feet (with Dave's help).  Having pictures of the feet really helps one see what they should be looking for when identifying tracks in the mud.

Thought I'd share the feet/paw pictures.

I'll post more information about Mink in the future....

Above: the right front paw of the road-killed mink.  Check out the slight webbing between the toes.  Also important to note is the shape of the inter-digital pad (i.e., pad between the toes).  It's that pad which gives mink tracks that crescent-shaped imprint directly below where the toes register in their tracks.

Above: The rear left paw of the road-killed mink.  Again, note the webbing and crescent-shaped inter-digital pad.  Also, five toes...but you may be able to see why one of those toes doesn't always make an impression.

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The D.O.R. Gray Fox (Urocyon cinereoargenteus).  The downside of being a wild animal in suburbia, is that you face mortality from a variety of sources that you otherwise wouldn't face in a more natural setting.  A great example of which is mortality due to vehicular traffic (see also Temple et al. 2010).  I'll post more specifics about carnivores in suburban lanscapes at a later date...but for now....I'll tell you about the road-killed Gray Fox we had the opportunity to see this week.

Above: the road-killed Gray Fox that we were told about on 6/23/2011.

This individual was not encountered at our normal study sites (nor on the road as we drove to our study sites).  Dave and I were working in the office one afternoon...data entry...data analysis....etc., when a colleague stopped by.

He told us of a freshly dead fox on the road not far from campus.  He said it had not been there in the morning, but was there now (several hours later).  He said it looked mostly intact.

Dave and I jumped up and hopped in my truck to check it out. 

Within about 30 seconds we found him......laying stiff in the road just about at the middle of a busy suburban intersection.  So busy, in fact, it had a stop light.  On one side of the road was suburbia...densely packed with houses.  On the other side was a large wooded buffer associated with a corporate headquarters of some kind.

We drug the little fella off of the road with garden rake and donned some gloves.  Took some measurements, got a GPS reading, and snapped some photos.  The body was pretty stiff with rigor mortis, but I was able to pry the legs apart enough to see that it was a male.  It was in perfect condition....the skull appeared intact...the pelt in good shape aside from being split along the shoulder and part of the front leg.  Would have made a fantastic museum specimen.  Unfortunately, I don't have a good facility to deal with a dead critter this large.

So we had to leave him there.  Seems like a massive waste, but we submitted our data to the state wildlife commission.

Among the photos we took were some good shots of the paws.  As with the mink, I think seeing the actual paws of an animal can be very helpful in learning to identify tracks in the wild.

The pictures below are all of the front right paw.  Due to rigor mortis, I couldn't get a very good shot of the back paws (and we were trying to do this along a busy roadway...so we were working quickly).

Above: in this picture, the pads of the digits (i.e. toes) are in focus.  You can really see the details of these pads, including the dermal pappillae (i.e. which essentially are the "finger prints" of this individual fox). 

Above: in this picture, the interdigital pad (closer to the heel) is in better focus and you can also see the dewclaw (near the thumb of my glove).  The dewclaws don't usually register in the track the animal makes.

Above: the same paw with a ruler for scale.  The Gray Fox really is a pretty small critter.

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The Gravid Wormsnake (Carphophis amoenus):  This is a very commonly captured species at our sites, and I've reported capturing them in the past.  However, on Thursday we first noticed definitive evidence that the females at one of our sites are gravid (i.e. carrying eggs).  I had thought previous females looked as if they might have eggs....but the one we caught this Thursday has eggs that are clearly visible in the second picture below.  

It's that time of year for the egg-laying snakes and turtles!

Above: the gravid female and juvenile wormsnakes captured in an upland forest drift fence this week.  They were found in one of the pitfall traps.

Above: the whitish blobs in her belly (visible through her ventral scales) are individual eggs.  It appears she has four eggs ready to be laid.

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The Southern Two-lined Salamander (Eurycea cirrigera).  We captured this juvenile in a pitfall trap along one of our lowland forest drift fences.  It is the first time we've captured Two-Lined Sallys in the drift fences at this site (although we'd found them flipping rocks in the stream edge nearby).  We hadn't seen any this year at this site.  At our other site, we captured an adult in an upland drift fence back in May.

There's not much to add.....the pictures are just cool.

In addition, it's just another example of the juvenile amphibians we're seeing this week.

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The metamorphosed Spotted Salamander (Ambystoma maculatum).  You may recall that last week we were still seeing larval Spotted Salamanders (note: as larvae most salamanders are fully aquatic, breathing with gills and spending all of their time in water).  Last month we found many larvae in the ephemeral wetlands on-site, but slowly the numbers we captured began to dwindle, which meant they were metamorphosing (i.e. transforming from aquatic larvae to land-dwelling adults and leaving the water).  But until this week, we hadn't captured any juveniles that had metamorphosed and began living terrestrially (i.e. on land).

Finally, we captured a pair of them in the pitfall trap of a lowland forest drift fence.

Above: a small juvenile Spotted Salamander, just beginning his new life as a land-dwelling organism.

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The Adult Eastern Ratsnake (Pantherophis alleghaniensis).  You may recall that we captured a juvenile Eastern Ratsnake a few weeks back in a lowland forest drift fence.  In that post, I made mention of how different adult individuals look compared to juveniles.  Well, here's another chance to see what I mean!

This adult female was captured in a funnel trap along a grassland drift fence at the same site that we caught the juvenile.

You can see, she's very black....no real discernible pattern.

A very cool snake!  Back home, these are very rare (listed as "Special Concern" by the Wisconsin Department of Natural Resources).  Here, they are one of the most common large constrictors encountered (I've even caught them in the university's "community garden" just outside my office door).

Funny what a difference geography makes.

Above: although it may be possible to confuse the Eastern Ratsnake with the Black Racer (Coluber constrictor), there are two basic differences that most folks can figure out.  (1) if its warm out, the Racer will be gone almost immediately after you see it....they are FAST....while the Ratsnake is a bit more pokey.  (2) if you can capture the snake (and you will probably get bitten in the process...trust me) look at the underside.  The Racer's belly is basically solid-black with the exception of the area around the chin.  Although it also has a white chin, the Ratsnake often has a "checkerboard" pattern along parts of the belly....not the solid-black scales of the Racer.



Hopefully, we'll have more to report from our surveys next week.  And hopefully we wont have any more camera thefts!
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Literature Cited:

Fitch, H.S. 1960. Autecology of the copperhead.  University of Kansas Publications of the Museum of Natural History 13:85-288.

Temple, D.L. et al. 2010. Spatial ecology, survival and cause-specific mortality of gray foxes (Urocyon cinereoargenteus) in a longleaf pine ecosystem.  American Midland Naturalist 163:413-422.

Otter Pups?

This week, as we scoured the river banks for good tracks to make plaster casts of, we again checked on our otter latrine.

The otters are still using the latrine site that is down the bank and closer to the water (having all but abandoned the latrine on the upper bank where the camera is).

I debated moving the camera down to the new latrine.  However, seeing as there's a low-life camera thief about....and it would be hard to move it and not have it somewhat exposed....I'm reluctant.

Anyways, this week we noticed something new about our otter scat: some of the scat appears to be from offspring: its much smaller than the other scat deposited there recently, and smaller than any of the scat I've seen at that site before.

Above: The new otter latrine site as of 6/23/2011.

Above: Note the smaller scat that is now present (example circled in red).  Compare to the much large scat at the top of the picture.

I wish I could get pictures of the actual pups and not just their leavings...... 

I just don't think I can risk another camera to do it!

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Notes on River Otter Reproduction:

According to Melquist et al. (2003) a significant amount of research has been conducted on the reproductive biology of River Otters.   One of the most interesting aspects of otter reproduction, in my opinion, is that they are capable of delayed implantation.  Many members of the Family Mustelidae (including several species of otter) are capable of this.  Delayed implantation is a phenomena by which the fertilized embryo does not immediately implant to the uterine wall.....instead it goes into a state of developmental dormancy.  This state of dormancy may last for extended periods of time (sometimes hundreds of days; reviewed by Melquist et al., 2003).  The advantage of delayed implantation is that the animal can then time implantation of the embryo, so that the energetically demanding action of being a pregnant female AND nursing newborn pups occurs at a time when resources are highest.  I'd say that's a pretty cool survival strategy!

Otters are also induced ovulators, unlike female white-tailed deer, coyotes, racoons, etc. who go into estrus at regular intervals (usually the same time each year)..which is called spontaneous ovulation.  For River Otters, the act of copulation with a male causes the female's ova to be released for fertilization.  This strategy is also similar to that of many felines (such as African Lions), who are also often induced ovulators.

Parturiation (i.e. birth) dates vary for this species, and range from January to May, depending on geographic location, and litter size varies from 1 to 6 pups (reviewed by Melquist et al., 2003).

Literature Cited:

Melquist, W.E., P.J. Polechla, Jr., D. Toweill. 2001.  River Otter (Lontra canadensis). In Wild Mammals of North America: biology, management and conservation (second edition), G.A. Feldhammer, B.C. Thompson and J.A. Chapman (eds.).  The Johns Hopkins University Press

SONUVA....BLEEPITY BLEEPING BLEEP!

Well, camera thieves struck!

Yesterday, we set a camera at a new location along a river.  There had been significant otter activity in the area...we had seen a mink there last month....there was a beaver sighting at the time of camera deployment AND we'd observed yellow-crowned night herons nearby.

Perfect place, right?

WRONG! 

I broke all of my own rules, which was stupid. 

We were in a rush.  So I forgot to put my name on the camera (stupid).  We didn't have a security box, so I just python locked the camera through the plastic brackets on the camera body (stupid).  AND the water in the river was low, so I didn't realize how easy it would be for someone to rock-hop over to the bank where the camera was (stupid).

We were only going to leave it there for a few days, and we'd be by the spot every day to check on the cam.  I figured we were safe (stupid).

The worst part is that the camera wasn't the only thing stolen.  We had placed it somewhat near the turtle trap we'd been deploying as part of our surveys.  This morning, I waded out towards the turtle trap...and didn't see it at first (figured I was just missing it in the water from a distance).  Then, I glanced over to the camera and saw the python lock around the tree with NO camera attached.

"Someone stole the camera", I said to Dave.

"They also got the turtle trap", Dave responded.

We looked over to see the two cinder blocks that we use to secure the trap laying in the water...between them the metal of the sardine can used as bait reflected the sun weakly through the murky river.

The had busted the plastic brackets on the body of the camera to steal it.   Then they waded into the river and untied the blocks, dumped the bait can and stole the trap.

Idiots.

Guess I'll inform the police......

The camera was not the highest quality (a Tasco, that we were trying out). 

I hope it doesn't work and the thieves get some sort of shock from an electrical short, or something....

Had such high hopes for some nice otter and mink pics, too.

Mr. Thief...whoever you are...just remember....Karma's a bitch.

Herpin' In the Sandhills Part V: Filling in the Gaps

Above: habitat typical of the southern Hognose snake (Heterodon simus).  Jeff allowed us to help him track an individual that he had tagged with a radio transmitter (see Dave above with the antennae).  Unfortunately, the individual was underground and we didn't get to see it.  Cool habitat, though!

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I'm going to take you both back to the Sandhills and back in time (to April of 2011).  I'm nearing the end of my series about our trip to the sandhills, which has already covered the Cottonmouth, the Scarlet Kingsnake, some cool amphibians, and the Cornsnake and Bullsnake.

Before I end with possibly my favorite encounter of the trip  -I must really stress the word possibly in this sentence- , I'm going to fill in the gaps with a few more reptile encounters that aren't really long enough to justify their own post at this point.  This is especially true considering that this trip is already going to result in SIX blog posts!
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The Banded Watersnake (Nerodia fasciata).  Up in our neck of the woods we have the Northern Watersnake (Nerodia sipedon), which I've posted about before.  In the Sandhills, for some reason, the Northern Watersnake is replaced with the Banded Watersnake.  Both have similar ecological needs (habitat, food, etc.).  Why one likes the Sandhills and one likes the Piedmont...who knows?  Maybe the Banded Watersnake can better handle the drier conditions in the Sandhills?  The two species are found sympatrically (together) in the areas where the Piedmont and the Sandhills meet, and will apparently hybridize (reviewed by Gibbons and Dorcas in their 2004 book: North American Watersnakes: a natural history, University of Oklahoma Press). 

Regardlesss, this species was fairly common around the hatchery.  I saw more than one dive into the water from the rip-rap along the banks before I could hope to get a hand on them (and I have to admit being more hesitant here, because I knew there were Cottonmouths around). 

I've found very similar scenarios in the upper Midwest with fish hatcheries and watersnakes (although up there we only have the Northern Watersnake).  These hatcheries attract amphibians, which are a primary food source for most watersnake species.  In fact, I recall catching a few Northern Watersnakes in Wisconsin at a hatchery, only to have one vomit up three freshly eaten Bullfrog tadpoles.

The biggest issue with watersnakes is that they are stinky!  If you grab one be prepared to get musked with some of the most unpleasant-smelling fluid that comes from an animal, this side of a skunk.

Oh....and they're also biters...but that's as much a badge of honor as anything.  I actually prefer the biting to the musking.   ;)

Above: three pictures of a Banded Watersnake that was captured at the hatchery during our trip to the Sandhills.  If you ask me, it's quite a pretty individual. The pattern on the head is very nice.

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Yellow-Bellied Sliders (Trachemys scripta scripta):  There is a drainage ditch that runs through a portion of the fish hatchery property.  There is a point where this ditch runs into a cement pit....and the water is apparently then directed back to a natural stream...or maybe the sewer...I'm not sure.  Anyways, it's a trap for alot of herps...they fall in and can't get out.  I'm told that folks who visit the hatcher and are in-the-know always check the pit.

This time, the pit contained a handful of hatchling Yellow-Bellied Sliders.

Above: two pictures of hatchling Yellow-Bellied Sliders found in the cement trap at the hatchery.  Note the black dots on the humeral scutes of the plastron.  These distinguishes this species from the River Cooter.

Yellow-bellied sliders can be difficult to distinguish from the River Cooter (Pseudemys concinna concinna).  Both are dark with yellow lines around their heads and arms....both have yellow plastrons (lower shells).  But most of the time the Yellow-bellied Slider has characteristic dark circles or dots on the humeral scutes near the head (see pictures above).

These turtles are related to the Red-eared Slider (Trachemys scripta elegans), which is often sold in pet stores.  The Red-eared Slider is also an invasive species in many areas around the world, as pets are often released in water bodies outside of their natural geographic range.

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Southestern Five-lined Skink (Plestiodon inexpectatus):  I've posted about finding the plain-old Five-Lined Skink (Plestiodon fasciatus) back up in the Piedmont.  The Southeastern Five-Lined Skink is very similar....and basically can be distinguised by counting the number of labial, or mouth, scales between the eye and the nostril, or looking at the size of the scales that line the underside of the tail.  Either way, it requires you to catch them and scrutinize them pretty closely. 

We found oodles of these guys flipping boards and pieces of tin....pretty much everywhere we went.  

Members of this genus (Plestiodon, which used to be Eumeces) are very common in our fine state.  Usually associated with fallen woody debris (bark, logs, leaf-litter) in woodlands or semi-open woodlands.  They root around for invertebrates.  The picture of the male, sporting the red-head, is one I've posted before.  This was an individual that we found on our Sandhills trip.

Above:  Skinks like to bite!  It's a last ditch effort to escape predation.  They will also undergo what is technically referred to as caudal autotomy.  This is where an individual purposefully separates its tail from its body.  The animal usually does this when captured by a predator.....the tail keeps wiggling after it has been separated, and apparently distracts the predator enough for the skink to make a hasty escape.

Above: Skinks even make good living jewelry for the fashion-savy individual on a budget.

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Only one more post focused on what we found during our trip to the sandhills is forthcoming. 

Stay tuned!

Week's End Survey Round Up IV: Applied Knowledge.

It's rare that a camera trap picks up nice photographs of scenery.  Usually, it requires the camera to take pictures without an animal in-frame...and then it assumes you've chosen a spot for your camera based on it's scenic value (and I never do...I'm choosing based on potential wildlife activity in the area, and the two things never seem to coincide for me).

Anyways, the picture above really struck me for some reason.  The green is so saturated in the picture...everything's lush...the sun barely peeking through in the upper right corner.  It's not a scenic mountain vista or anything, but a simple riparian corridor.

Just looks nice, is all.

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Well, we've added another stop to our trapping survey circuit every day. 

This one is as much for fun/practice as it is for real data acquisition....you'll see what I mean by this in a second....

Basically, after the Mammal Tracking and Small Vertebrate Survey Workshop that was held at the university (taught by Jim Halfpenny, and myself).....we had left-over Plaster of Paris.  It was technically Jim's.....but he said, rather than trying to ship it home, or lug it on the plane, he'd just give it to us (very nice of him!). 

Dave was a workshop participant.  I co-taught, but focused on surveys with drift fences, coverboards, etc., so I didn't get to do the tracking/casting part of the workshop.  I had done track casting in the past (as a participant in one of Jim's other workshops that the university sponsored last year).  But, I hadn't done it since last year.  So I'm rusty. 

Luckily Dave remembered alot of the rules about mixing the plaster.  It's important to get the plaster to the right consistency, or it wont dry fast enough.

Above: it helps to set up a work station for the mixing, if such a spot is available.  Here, we prep the plaster on a stairway installed for putting canoes into the river.

While the plaster is being mixed, someone else builds a wall of dirt around the desired tracks.

Above: prepping the area around a pair of suspected Mink tracks for plaster.

Above:  preparing the mixture for two nice sets of suspected Coyote tracks.  These tracks were not far from the huge pile of 'yote scat I posted about last week.  The location is along an entrance road into a state natural area, where a puddle is often present and the soil is saturated.  Great for tracks!

Then, the plaster gets dumped in.

Above: Dave pouring the plaster over some suspected Mink tracks from along the river bank.

And then you wait....

The plaster is such that it dries and solidifies even on saturated soil and mud.  So, after a half hour to 45 minutes.....the plaster is ready to be removed, rinsed and the cast gets dried in the sun for a while....

Above: the pair of suspected coyote tracks with plaster poured on top and waiting to dry.

Above: our track-cast library after the first week.

So, to-date we've been making track casts of species we already had evidence of on-site (i.e., Raccoons, Mink, Eastern Gray Squirrel, Coyote).  So, we aren't neccessarily proving anything we didn't already know.

However, being able to cast tracks is a great skill.  You can use it to gain quality evidence of a species' presence on-site, if you don't have camera traps available.  Having the casts on-hand also means that they can be used as a teaching tool in the future.  It's a way for both of us to hone our tracking skills...and apply some knowledge picked up during the worskshop taught by a tracking expert.

It's also fun as hell!  Ironically, Knapperbill over at the Rural Path also had some fun with casting tracks this week.
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The Common Snapping Turtle (Chelydra serpentina).

This little fella was in the path we were walking along this week.  He was only about 40 yds from the edge of a large old field/grassland, but over 100 yds from the nearest water source (a small feeder stream).

What was a turtle this little doing so far from water?  It's obviously dangerous for a little turtle to leave the water at this age (even a little snapping turtle).  Their shells are pretty soft at this age, and...as you can see...when they are this small, they are completely passive.

One could argue that it's a hatchling, just emerging from the nest...the size is almost correct.  But just a tad big.

It's not completely outside the realm of possibility to assume that this animal was laid in a nest somewhere near the edge of the grassland.  Plenty of sun there to keep the nest warm and the eggs developing.  Female snappers will travel HUGE distances to lay eggs (1.6 km, or nearly one mile, reported for females in Michigan, Congdon et al., 1987).  Thus, travelling over 100 yds from the nearest stream is no problem for a nesting female.

But, most females lay eggs from May 15-June 15 in North America.  The incubation period is 75-95 days...so I wouldn't expect hatchlings to poke out until late August.

Females of some species will "double-clutch" in a year (lay one nest of eggs in the spring/summer and another again in late summer).  These hatchlings may hatch in the nest in fall, but overwinter in the nest and then emerge the following spring.  This phenomena has not been observed often in the Common Snapping Turtle, to my knowledge.

So...I'm alittle stumped on why this little fella was where we found it.

Houdini:  This adult White-spotted Slimy Salamander (Plethodon cylindraceus) caught me by surprise.  I wasn't surprised we caught one (they are our most frequent salamander).  I was surprised by the fact that this one has managed to squeeze itself almost entirely through the mesh of our funnel trap!  How on earth it got its head through is beyond me (the head looks about 20% wider than the mesh apertures to me).  They must be flexible.  Plus, it doesn't hurt to be....well...slimy.

When we came up to the fence, he was caught at the pelvis.  He wasn't stuck too bad, but becuase of the angle I think he just couldn't get enough purchase to pull himself through mesh the rest of the way.

We gently helped him through and he was none-the-worse-for-wear, aside from alittle skin missing from the tail.

The Larval Salamander:  There are several ephemeral wetlands at one of our sites.  "Ephemeral" meaning that they hold water part of the year, but not all year.  Usually, in the summer when it's dry....these wetlands dry up.  In the winter/spring, however, they have water.  This makes them perfect breeding habitat for amphibians.  Primarily due to the fact that, because they are ephemeral, fish cannot live in these wetlands.  Fish eat amphibian larvae and eggs.  So, no fish = good news for amphibians.  The importance of these small ephemeral wetlands cannot be overstated, from a standpoint of biodiversity conservation.

We usually toss a few minnow traps in these little wetlands.  It allows us to see what sort of amphibians are breeding in the ponds.  We've found many tadpoles, mostly Hylids (probably Upland Chorus Frogs and Cope's Gray Treefrogs, as both have been heard breeding around the ponds).

We've also been getting salamander larvae for several months, although the numbers we're catching are smaller these days.  We catch larvae of primarily Ambystomatid salamanders, or salamanders of the Genus Ambystoma.  I'm fairly certain the species is Ambystoma maculatum (the Spotted Salamander).  They are very common in aquatic ecosystems around here, and I captured adults near the ponds this spring (see A Good Day for Herps, posted on March 23, 2011).  It's possible that these are the larvae of Ambystoma opacum (the Marbled Salamander), as we found them hanging around the ponds last fall.

These just sort of look like Spotted Salamander larvae to me.  You can almost see the little dull spots forming on these guys already in the pictures below.

Not very scientific, I know!

Above: the salamander larvae captured in minnow traps on 6/14/2011.  Note the external gills, which look like fleshy lumps near the neck.  In the water, the gill filaments separate and the gills appear large and bushy.

Literature Cited:

Congdon, et a. 1987. Morphological constraints on egg size: a challenge to optimal egg size theory? Proceedings of the National Academy of Sciences 84:4145-4147.