Podcast on social rattlesnake behavior

If you'd like to take a break from reading, but not rattlesnake behavior, check this out:
The Reptile Living Room: Rattlesnake Behavior with Dr. Rulon Clark

This is a great interview with my friend Rulon Clark about his research, including social behavior of timber rattlesnakes. Dr. Clark is now a professor at San Diego State University, where his lab continues to do cool stuff with rattlesnakes and other reptiles (for example, check out Strike, Rattle, & Roll).

Scenes from a new den

We were recently told about a new social rattlesnake den in the Galiuro Mountains. We hiked in to check it out, saw one western diamond-backed rattlesnake (Crotalus atrox), and decided to set up one of our timelapse cameras. The video below is from the first two days of our monitoring, and we were a little surprised at all the activity:



That video is a little long and it’s easy to miss all the visitors, so here are stills of all the reptiles we spotted.






This is a juvenile Sonoran whipsnake (Coluber bilineatus). The closely related striped whipsnake (Coluber taeniatus) often shares dens with Arizona black rattlesnakes (Crotalus cerberus; see Are aggregations of Arizona black rattlesnakes stable and complex social groups?).







A gila monster (Heloderma suspectum)! It is not unusual for Gila monsters to share dens with western diamond-backed rattlesnakes and Sonoran Desert Tortoises (Gopherus morafkai). However, this Gila checks out the den only to turn around and leave. Could it be looking for a date? It's awfully late in the year for Gilas to be out and about.







Patch-nosed snake (Salvadora spp.) This is not a snake we have yet seen in any of our other dens. In this video, the patch-nosed appears to be checking the den out before moving on. Future videos may show if this snake continues to use the den.

There were a couple feathered reptiles here too (birds). Did we miss anyone? Who else will show up at the new den? Stay tuned...

Stop Roundups!

Sorry for the interuption from our regularly scheduled program, but this is important.
Enjoy our blog posts?
Like snakes?
Then consider signing this petition to stop the unnecessary and cruel rattlesnake slaughter:
Ask Texas Department of Parks and Wildlife To End Rattlesnake Roundups

A day in the life of a rattlesnake family

Rattlesnakes take care of their babies.

Yep, they really do. But, what does "care" look like in a snake? Do they feed their young like a mother bird? Do they keep them warm? Do they protect them from predators? With the exception of feeding, rattlesnakes care for their offspring in familiar ways. The following is a timelapse video (taken at 1 minute intervals) that illustrates a typical day for a new rattlesnake family. The large, black snake is Cap Mama, a female Arizona black rattlesnake that gestated with four other females and gave birth in late August to seven neonates. This video was taken when the neonates are just two or three days old.


Now let's look a little closer at some of the behaviors in the video:


Before the neonates emerge for the day, Cap Mama looks out as if making sure it is safe for the neonates to come out. Here she looks toward the camera...



And then she looks away from the camera. We have observed this "lookout" behavior by several different females.



The neonate in the foreground of this photo is starting to stray from the group and Cap Mama notices.



A gentle tap from Cap Mama reminds the neonate to stay with the group. We have also observed the females blocking neonates from straying too far (see A rattlesnake helper?).



The neonate responds by returning to the group and Cap Mama heads back in as well.



In this rattlesnake species, adults are darker than neonates and thus may be able to gain heat easier. By allowing neonates to sit on and near her, Cap Mama may be provisioning her offspring with heat (rattlesnakes are ectotherms: they depend on their environment for heat instead of producing their own like we do). And Cap Mama's larger size means she'll garner and release heat, perhaps even into the night when the family is tucked away in their refuge. Keeping warm helps a young snake develop, shed, and get ready to leave the nest and hunt on its own.

A rattlesnake helper?

Priscilla, Lois, and Arli spent their pregnancy together at a rookery from May through August, 2010. Arli moved away to a private nest shortly before giving birth.
Priscilla & House, 1 September 2010

On 30 August 2010 we observed Priscilla (pregnant adult female) discouraging House (neonate / newborn) from potential exposure to a human predator. Because Priscilla was pregnant at this time, House had a different mother. To our knowledge, this is the first observation of helping - where an animal cares for another's offspring - in a snake. Perhaps this is why some female rattlesnakes aggregate during gestation and remain together after giving birth.

15:27 Priscilla (adult female) and House (neonate) are at rest in a shaded rock shelter.

15:28 House moves restlessly in cover and then begins to move toward open ground.

15:29 Priscilla swiftly confronts House before he wanders away from cover; her posture is unusually rigid.

15:31 House stops, turns around, and coils in cover. Priscilla's head returns to her coils.

Ménage à trois (part 2)

(if you haven't already, see part 1)


When we left our 3 gophersnakes, Bluto had just interrupted courtship between Popeye and Olive Oyl and was biting Popeye repeatedly along his body. Popeye released his bite-grip on Olive Oyl and she fled so fast that we were unable to follow. Bluto continued biting Popeye, making him to wince but not retaliate. Instead, Popeye seeks refuge in a nearby burrow. In his fervid biting, Bluto barely notices that Popeye has escaped, actually biting himself a couple times by mistake. Finally realizing that his competitor is sidelined, Bluto resumes searching for Olive Oyl, who had a 2 ½ minute head start.

Bluto appears to be in a hurry, and while he initially showed brief reactions to close encounters with us, he no longer expresses concern. He flicks his tongue almost continuously, halting almost imperceptibly several times a second to deliver particles into his mouth. Undoubtedly, Bluto is following traces of Olive Oyl, but apparently her trail is not clear. He travels in wide loops, backtracks, and even ascends a pine tree. Perhaps Olive Oyl has passed through this area more than once. And the wind must make his search even harder!

Popeye’s urges can wait no longer. We find him peering from the burrow only 3 minutes after entering. After five more minutes, he locates Olive Oyl’s scent trail, and heads off in the same direction as the other two.

He appears to be a little more careful than Bluto, pausing to hone in on the path ahead. We try to keep tabs on both males as they move about, but we are distracted by a beautiful rattlesnake and Popeye slips away.



After about an hour Popeye reappears, coming within just a few meters of Bluto. He appears to pass Bluto, and we again lose him as he cruises on through the vegetation. Finally, at 1417, 80 minutes after we last saw her, we find Olive Oyl being courted by Popeye on open ground beneath a tree, 113 meters NE of their roadside rendezvous (see part 1). Moments later, Bluto finds the pair, Olive Oyl slips away, and conflict begins anew.

In a repeat of part 1, Popeye is first to find and court Olive Oyl, but they are interrupted by latecomer Bluto, and the female flees. With an enduring calm, Popeye once again slips from Bluto's sway.

To be concluded...

Desert Dining

On a humid Sonoran Desert evening we met up with Roger Repp and Gordon Schuett at their study site along with some old friends from near and far. Wandering the washes, we find a juvenile desert rodent stumbling out of a hackberry bush into the dry stream channel. It turns at our approach and manages a couple of hops away before spiraling onto one side. While at first we attribute its ungainly locomotion to its youth or perhaps being blinded by a flashlight, it soon becomes clear: its situation is dire.



Six minutes after encountering the rodent, we spot a tiger rattlesnake (Crotalus tigris) emerge from the bushes about 10 meters downstream. It’s a beautiful male with a long, intact rattle, and he’s intent on finding his meal. This next video clip shows him scent trailing his prey.



Tiger rattlesnake venom is extremely potent, and this one knows his prey couldn’t get far. His search is slow but methodical; he may turn away momentarily, but he is quick to correct course and close in on his meal. In the following video, the tiger passes very close to the rodent, visible above the stick to the left. Portions of the film are sped up 3 times.



Observations like this are infrequently witnessed. By searching on foot, keeping our minds open to what may come, and being willing to sit and watch what unfolds were we able to observe this feeding event. That, and quite a lot of luck....

In the interest of full disclosure, this snake was captured after feeding. He is now being radio-tracked by Roger and Gordon, and further updates on this snake’s life will be available on Roger’s Suizo Report, posted regularly to John Murphy's blog: http://squamates.blogspot.com/p/roger-repps-suzio-report-page.html