Saturday, September 29, 2012

Is This Photo Real: Ten Foot Rattler in George West With Jackrabbit

I often get e-mails from people asking me about the authenticity of snake photographs. For example, a couple months ago I received an e-mail from a newspaper editor in Louisiana with the photo on the right attached. The entire e-mail consisted of a single line: "Do you think this photo is real?"

I could have answered, "Yep, that's a real photo of a snake." and gone about my day. But, I don't think that's what people really want to know. What they should be asking me is, "Is this snake really as large as I perceive it to be?"

I am sometimes accused of beating a dead horse on this blog, because many of my rattlesnake posts hit on a similar theme. It's true that I am running out of new and interesting ways of saying that when you look at a photograph, objects that are close to the camera (i.e., in the foreground) appear larger than objects that are in the background. This can cause the object in the foreground to seem very large when there is nothing else there. 

Those that accuse me of retreading familiar territory over and over again underestimate the internet phenomenon that is the myth of the giant dead rattlesnake. It doesn't seem to matter how many times I explain the photo tricks, whenever a new photograph pops up we have to start over again.

In any case, I did not write a blog based on the picture above when I first received it because there was no associated story, and it's no fun to write about (or read about, I presume) a picture without any sensational "details". Besides, it seemed like an isolated incident and hadn't gone viral.

Cut to a few months later, and the internet forums (like, here, here, and here) are abuzz with this picture.

And, now we have this:
" I have killed several over 6' and seen a bunch killed over 6', but I do not remember any with a body girth like this one has.
Killed near George West.
That’s a big Jackrabbit!! 
Keep your snake boots on,,,,,,,they make you so much more safe and secure,,,,,,,,,"
In addition to this text, one of the forums I link to above notes that this photograph was taken by a friend, and that the snake was ten feet long (3 meters) and again, eating a jackrabbbit. 

Okay-now we have something to work with. 

Presumably the author is referring to George West, Texas. The first problem is the rabbit identification. Now, this is not exactly my area of expertise but I think that the white puffy tail (together with the color patterning) means that this animal is a cottontail rabbit. Assuming that the location is correct, then this is probably a Desert Cottontail, Sylvilagus audubonii (can I get some feedback from mammal folks in the Comments?). This is an impressive meal to swallow whole, but cottontails are generally about half the size of jackrabbits, give or take.

The snake in the picture is a Western Diamondback Rattlesnake, Crotalus atrox. You can tell by the diamond-shaped patterning and the black and white tail. This species is found throughout Texas (except for the eastern portion of the state), including in and around George West. Western Diamondbacks could reach six feet long (1.8 meters) but this would be an extremely rare and giant snake. There has never been a Western Diamondback Rattlesnake (or any other rattlesnake species, for that matter) that, when reliably measured, came anywhere close to ten feet long. As I mention elsewhere, 

"There are no ten foot rattlesnakes...There are no eleven foot rattlesnakes.  There are no fourteen foot rattlesnakes. They don't exist.  Period. Want to know why I feel confident saying these things? Check out my FAQ. If an eight foot rattlesnake is found, there needs to be compelling proof presented because it is one of the top two or three biggest rattlesnakes ever found in the history of humans or rattlesnakes."

So, my verdict is that this is a real photo of a Western Diamondback Rattlesnake eating a cottontail. It looks large because of standard camera tricks that you should all be familiar with but it's likely about five feet long (1.5 meters), based on my best guess.

Friday, September 28, 2012

Friday Roundup: The Rattlesnake that Was a Hognose but Wasn't


Don't Worry, It's Not a Rattlesnake: When a snake was found crawling through Union Station in Chicago, Illinois last week, workers feared it was a rattlesnake. When an animal control company came to capture the animal, they reassured everybody that it wasn't a venomous rattlesnake, it was actually an Eastern Hognose Snake, Heterodon platirhinos. Actually, they were only half-right. Interestingly, the nature center that received the snake (why didn't anybody consider just letting it go?) did not catch the error either. It's a Northern Watersnake, Nerodia sipedon. The nature center correctly notes that Eastern Hognose Snakes prefer sandy soils, not exactly prime habitat for watersnakes. I have contacted the nature center to tell them of the correct identification so that they don't start wondering why their new arrival is starting to look a little dehydrated.


Support Nongame Wildlife in Georgia: When it comes to animals like bear, deer, turkey, and quail, there is seldom a shortage of the funds necessary to protect their populations. This is because they are considered game animals, in other words, these are the species that are frequently hunted, and there is a lot of interest in making sure these species stick around. However, when it comes to animals that are considered nongame wildlife, money can be hard to come by. The nongame division of the Georgia Department of Natural Resources gets money primarily from things like specialty license plates. So, if you're in Georgia, consider selecting a nongame wildlife tag. Speaking of nongame wildlife, the Gopher Tortoise, Gopherus polyphemus, (Georgia's official state reptile) is facing some serious conservation issues.

Close Encounters of the Stingray Kind: People pay a lot of money to swim with and feed stingrays (while disrupting their normal movement and foraging behaviors). You would think these ladies would look a little more excited at the opportunity to get up close and personal with one.

Be Glad the Fish Aren't Biting: A wakeboarder in Idaho suffers a tragic accident and loses several of his fingers on the water. Two months later, a fisherman finds one of the fingers in a fish he's cleaning.

Just Because It Is Cool: Check out this spectacular photo of two massive sharks hovering in the open ocean.

Are We Stumped? Finally, we are still waiting for someone to give us a definitive identification on this snake, possibly from Uruguay.


Wednesday, September 26, 2012

Readers Write In: The U.S.D.A. Needs You to Identify this Snake

"Hi Dave,

I received this picture from Josh F. with the U.S. Department of Agriculture asking if I could identify the snake (I couldn't other than to say it's a ratsnake-looking Colubrid). Josh told me the following info on the snake:

Snake was found roaming free in a cargo box (shipped from Uruguay) at the Miami International Airport. We don't know what type of cargo was in the box, but we do know it was not a shipment for the pet trade. Miami airport called Venom One (Miami-Dade Fire Rescue Venom Response Team) to have them ID the snake. They recognized it as not native but couldn't ID it, so they sent the snake on to the Florida Museum of Natural History in Gainesville where it now resides (as of yet unidentified).

Thanks!

Melissa M.
Auburn, Alabama"

And I thought this Gopher Snake from California last week was exotic. The only snake from South America I can reliably identify is an Anaconda. Thousands of animals from all over the world stop through Miami International Airport each year, many are destined for the pet trade, others are stowaways. This snake could be from anywhere but we have to assume that although it spent the day in Florida, it went to sleep the night before in Uruguay. 

So, I am counting on you, esteemed readership. What is this snake? I have my guess but I don't feel too confident about it.


Update: a number of people have complained about the picture quality so I've tried to clean it up.


Tuesday, September 25, 2012

Readers Write In: Can We Identify This Snake Before it is Killed?

"Hi Dr. Steen,

Earlier today I managed to capture a snake at the Fisheries station - genetics station where I work, I'm sure it's poisonous although I don't know my snakes, and I'm looking to get rid of it without killing it.  If you have any interest in wanting it, or have any advice on who to give it to, that would be great.  I didn't catch it outdoors or anything, I caught it inside where it still stays in a bin.

Could you help me with this, I don't like killing things if I don't have to.

Mike F.

Auburn, Alabama"


I have found that as a general rule, the less people know about snakes the more likely they are to identify any snake as venomous (I guess it's better safe than sorry). So I wasn't completely convinced by Mike's identification.

However, the venomous Cottonmouth, Agkistrodon piscivorus, loves to hang around fisheries ponds (free dinner!). So, I knew there was a distinct possibility that Mike had come across (and captured) one of these vipers. And they're not very popular.

I asked Mike to quickly send me a picture so I could first confirm that his snake really was a potentially dangerous species. At the same time, I brought a couple colleagues that were still in Auburn into the loop so that if the snake was a Cottonmouth, they could quickly and safely relocate the animal before it was given a death sentence. I got the impression that if Mike's supervisors thought this was a venomous snake, then they would require him to kill it, and he didn't want to do that. If it wasn't venomous, Mike was comfortable releasing the snake.

What do you think happened to the snake? 






Monday, September 24, 2012

Readers Write In: Who Would Win in a Fight, a Coral Snake or Black Racer?


"Dr Steen:  I have often heard (and read) that Black Racers keep all venomous species away.  My amateur Herpist friend pointed out that Elapidae (for readers, this is the family of snakes that includes coral snakes and cobras) eat other snakes.

Question:  If an Eastern Coral and a Black Racer came together, what would happen?  Would the Racer bully the Coral away?  Or would the Coral eat the Racer?

Thank you for any info you can provide.


Carmen"

    It's the age-old question-What would happen when two predators meet (i.e., who would win in a fight?)?

    First off, I think it is a misconception that Black Racers, Coluber constrictor, keep venomous species away. Black Racers are one of the most abundant snakes in the southeastern United States; if they were territorial or kept snakes away then there would be nowhere for other species to go. In my snake trapping and surveying efforts, I frequently find all kinds of snakes, including Black Racers, in the same area.

    That said, although other species, such as Indigo Snakes, Drymarchon couperi, are more famous for eating venomous snakes, Black Racers do it too. By no means are other snakes the primary prey of Black Racers, they are just not very picky about what they eat (the practice of eating snakes is called ophiophagy). Just check out these pictures of a Black Racer eating a Copperhead, Agkistrodon contortrix, in North Carolina. I have also seen pictures of a Black Racer eating an Eastern Diamondback Rattlesnake, Crotalus adamanteus (I wouldn't have believed it if I hadn't seen it). 

    However, I looked through the snake books that I had and I couldn't find any instances of a Black Racer eating a Coral Snake, Micrurus fulvius. That doesn't mean it can't happen, just that nobody has documented it yet. I did find some pictures online of this culinary event but I couldn't determine if it was a staged encounter.

    Coral Snakes, on the other hand, are well-known for eating snakes, including Black Racers. In fact, reptiles are their primary prey.

    So, what would happen if these two snakes met? I think it's likely that the bigger of the animals would try to eat the smaller one. And, if they were the same size...My guess is that they wouldn't take any chances and they'd both hightail it in different directions. 

   I would be interested to know if any readers have seen or heard of interactions between these two species.



-----------
Want to Learn More?

DR Jackson, & R Franz (1981). Ecology of the eastern coral snake (Micrurus fulvius) in northern peninsular Florida Journal of Herpetology, 37, 213-228


Sunday, September 23, 2012

Readers Write In: What Is This Snake In My Kitchen?


"Hello,

I am an Auburn faculty and yesterday night I found a small snake (about a foot long and a quarter to half inch thick) inside the kitchen of my home. I tried to capture it unharmed but because it was too quick even on the slippery vinyl floor of the kitchen and as the only implement I had at hand was a long-snouted pair of scissors, I had to catch it with the scissors which caused a wound. I have it in a bottle, and it is still alive, but not sure whether at this point it would be merciful to kill it or let it back into the wild. Also, I have no idea if it is venomous or not. I don’t feel good about injuring it and am emailing you to ask what the best course of action is now. 

Thanks for any help/advice you can provide.

HN
Auburn, AL"

  This is an unfortunate situation for everyone involved, but mostly for the baby snake, dangerous only to small frogs and fish. When informed of the species, HN told me that the next time an unwelcome serpent appears he will remove the snake in a way that is safer for the animal. Although I recommended releasing his guest, assuming that the wound wasn't too severe (reptiles are tough animals), HN was sad to report that the snake had died since his initial e-mail.

  What did HN find in this kitchen? How can you tell?


Saturday, September 22, 2012

Readers Write In: Can We Positively Identify This as a Rattlesnake?

"Can you positively identify this as a rattlesnake?  I found this in my front yard and it is now in a box. Help! 

Thanks for your help.

Judy"


   I told Judy that I was sorry to disappoint her but I could not positively identify this as a rattlesnake. I could however, positively tell her that it was not a rattlesnake.

  It was clear to me that this snake was not from the southeastern United States (where most of my identification requests come from). Although I was fairly certain about identity of this snake, a resident of the western United States, I asked Judy for some more information just to be sure.

"We found it in front of our house in the foothills of Fremont.  Both my daughter and granddaughter froze when they saw it strike towards our cattle dog.  The small snake continued to strike and hiss at everything that got near it.  We got it in a box by using a toy fishing net.  We will give it to our landscapers to release it away from the homes.  With your help in identification this snake will be released somewhere in the Mission area foothills. Now we've just found a tarantula walking around.  I feel like I'm living in 'Wild Kingdom'.

Judy
Fremont, CA"

 When harmless and non-venomous snakes try to defend themselves, they are often mistaken for rattlesnakes. This might be because many different snakes shake their tail when they are threatened. Without taking a close look, a shaking tail might look like a rattle...but it's not.


 I've never seen the snake Judy found in her front yard, but there is a close relative living in my neck of the woods. This species is also a big hisser, but it's just a big bluff...they very rarely bite.

  What kind of snake is this?




Friday, September 21, 2012

Friday Roundup: Psychic Crocodiles and Making Way for Tigers

Can Crocodiles Predict Earthquakes? Over at the Croc Blog, Adam Britton takes on a recent report suggesting that a captive (actually the largest crocodile in captivity) crocodile in the Philippines may have predicted an earthquake seconds before it occurred. Crocodilians are very good at detecting subtle and low frequency vibrations. This is because they use these vibrations to communicate and detect prey. So, although this crocodile may have reacted to some vibrations just prior to an earthquake, it's a stretch to say that there were any predictions involved.

Living Alongside Wild...Tigers: There have been a lot of reports about a recent scientific article demonstrating that people and tigers and India have worked out a clever way of sharing the same space.  People don't want to run into potentially dangerous felines when they're walking to work and tigers don't want to encounter anybody that could be a potential poacher. So, when they need to use the same paths, they do it at different times of the day.

Amazing Wildlife Photography: This is a must-see, a slide-show (with narration) of some incredible wildlife shots submitted to this year's Veolia Environment Wildlife Photographer of the Year Competition. Which pictures stood out to you?

Conservation on the Cayman Islands: A great summary of the conservation threats and hopes facing a handful of species found only on these small Caribbean islands.

Indigo Snake Conservation in Alabama: In his blog, Life is Short but Snakes Are Long, Andrew Durso provides a great summary of the recent research surrounding the reintroduction of the Indigo Snake in Conecuh National Forest.

I Hear You: An columnist for the Henderson State University (Arkansas) newspaper vents about a constant parade of dead rattlesnake pictures and outlandish reptile myths.


----------------

Want to Learn More?

Carter NH, Shrestha BK, Karki JB, Pradhan NM, & Liu J (2012). Coexistence between wildlife and humans at fine spatial scales. Proceedings of the National Academy of Sciences of the United States of America, 109 (38), 15360-5 PMID: 22949642

Monday, September 10, 2012

Upcoming Event: Alabama Partners in Amphibian and Reptile Conservation Annual Meeting




  This just in from L.A.W. guest blogger Brian Folt, a great opportunity to get updated on important amphibian and reptile research and conservation in Alabama and nearby:    

   The Alabama Chapter of Partners in Amphibian and Reptile Conservation (ALAPARC) is holding its annual meeting September 28-30 at the Dauphin Island Sea Lab. For those interested in the ecology, biology, and conservation of southeastern herpetofauna, this may be an informative and fun meeting to attend. Check out the meeting website for more details. Friday and Saturday there are field outings planned to look for local animals; specifically, researchers from University of Alabama – Birmingham will be leading a search for Diamondback Terrapins (Malaclemys terrapin), while folks from Auburn University will be leading other (likely more exciting) adventures. There are still slots available for presentations (either talks or posters), so don’t hesitate to share with everyone about what you have been doing to study and conserve herpetofauna (Alabama or otherwise).

            So far, the list of talks includes:

David Nelson – Road-kill survey of Alabama Red-bellied Turtles (Pseudemys alabamensis) on the Mobile Bay Causeway – XI

Craig Guyer – Get ready for name changes: Emerging taxonomic issues in Alabama’s herpetofauna

Andrew Cantrell – Thinking outside the box: Recycling materials for herpetofaunal research

Thane Wibbels – History of the Kemp’s Ridley Sea Turtle in the Gulf of Mexico: The biology and politics of saving an endangered species

Jimmy Stiles – Eastern Indigo Snake (Drymarchon couperi) repatriation in Alabama


Chris Murray – Alligators in Alabama: Ecology and management of a population at Eufala 
        National Wildlife Refuge

Brian Folt -- The Alabama Riverfrog Initiative: Recent successes and a call to arms

B. Folt – The distribution and status of the Alligator Snapping Turtle (Macrochelys temminckii) in Alabama

Scott Goetz – The natural history and conservation of Canebrake Rattlesnakes (Crotalus horridus) in Virginia

Sean Graham -- The impacts of invaders: Basal and acute stress glucocorticoid profiles and immune function in the Eastern Fence Lizard (Sceloporus undulatus) threatened by invasive ants (Solenopsis invicta)

A number of folks have also signed up to present posters!

Sierra Stiles – Habitat use of introduced Eastern Indigo Snakes (Drymarchon couperi) in Alabama

Melissa Miller – Habitat association of snakes in Everglades National Park with implications for Alabama snakes


Kristin Bakkegard – Movement within a population of the federally-endangered Red Hills Salamander (Phaeognathus hubrichti)

Kayla Beiser – Epigenetic influences of methylation inhibitors on Dmrt1 expression in the Pond Slider (Trachemys scripta)

    And I hear the organizers stocked up on great beverages for festivities. Registration ends September 14, so get on the horn, folks! Hopefully we’ll see you all there.

Tuesday, September 4, 2012

Readers Write In: Now This is a Rattlesnake

  It must be snake season, based on the number of identification requests I'm receiving lately. At least when it comes to rattlesnakes, that makes sense. In the southeastern United States, rattlesnakes tend to mate in the late summer and fall. During this time, it's more likely to find a big male rattlesnake cruising through your yard or crossing the road as they look for females. Just ask Anne.

"Subject: Info please

Hi,

I live in Georgia and just shot this snake a few minutes ago.  Can you please identify it for me?  Since I didn't want to get too close, it appears to have 10-12 rattles.  Also, is it possible to ID a male vs. female?

Thank you so much and I hope you are having a nice Labor Day.

Anne

Georgia"

   I was happy to inform Anne that the snake she found was a Timber Rattlesnake, Crotalus horridus, a large, venomous species found throughout the eastern and central United States. In colder climates, Timber Rattlesnakes den together in large groups during the winter, often in rocky areas. In the spring, they'll emerge and search for things like squirrels and rats to eat. The species has become very rare in the northeastern United States but it is still hanging on in Georgia.

   It's hard to see a big beautiful snake killed, so, in answering Anne, I told her that I hoped she hadn't killed it for no good reason. She responded, "Thank you so much for the information concerning the Timber Rattlesnake.  I would never kill a snake that was in the woods, minding his own business. As I was walking to the mailbox, this snake became aggressive." 

  Although the safest course of action when encountering a venomous snake is to head in the other direction, I can understand wanting to get rid of a large venomous snake around the home. That's why I created this brochure, which I provided to Anne.

  Determining whether this rattlesnake is a male or female is a little trickier. Male lizards and snakes have paired reproductive organs called hemipenes (singular: hemipenis). These structures are internal (except during mating) and best imagined as pockets. By inserting a small probe into a snake's cloaca (the opening that has both excretory and reproductive functions), you can determine if there are hemipenes. Basically, if the probe goes in relatively far, you know that you're within the pocket of a hemipenis. This is the method that I use when conducting a snake study because it's important be accurate.

   Using a probe is a sure-fire way of determining a snake's sex. However, there are ways to guess. Male rattlesnakes fight for breeding opportunities. These fights are usually won by the larger animal. As a result, bigger males tend to have a greater chance of passing on their genes. As a result and over time, male rattlesnakes became larger, on average, than females (who don't normally engage in combat). So, if you find a very big rattlesnake, there's a good chance it's a male. Edit: Melissa Amarello notes (in the comments) that another theory explaining this difference in size suggests females stop growing after they become sexually active while males keep getting bigger. Another way to sex snakes is by looking at the tail. Because male tails contain hemipenes, they are usually bulkier and longer than those of females.

Sunday, September 2, 2012

Readers Write In: Is This A Rattlesnake?

  Most of the snake identification requests I receive are from people worried that a harmless snake they found around their home or business (usually a ratsnake) is actually a potentially dangerous and venomous species. This message is a little different.

"Subject: Can u identify this

I know its a baby it was out front of the firehouse this morning in Goose Creek SC guys are saying baby rattle snake.

Thanks

Steve S.

Goose Creek, South Carolina"

   This isn't the first time Goose Creek has made it onto this blog. There are actually rattlesnakes in the area, but this is not one of them.

   Distinguished readership, please try to identify this snake. Do not be shy if you are not a snake expert; by offering your guesses we will know similar and confusing species and can then offer suggestions on telling them apart.

   For those of you that are relatively confident about the species identification, I offer the following challenges:

1. In addition to identifying the species, describe how you came to your conclusion, including how you differentiated this snake from any close relatives, if any.

2. Is this snake an adult or a juvenile? How can you tell (besides the size)?

3. Describe some interesting natural history information related to #2 (if you answered #2 correctly, you will understand #3).

4. Describe the morphology and behavior that may make it easy for some people to mistake this snake for a rattlesnake.

Steve has already received my answer but now I am looking forward to hearing yours.