How old is a rattlesnake with one rattle

Diet Rattlesnakes eat mostly rodents, but may also eat insects and other reptiles. Behavior When rattlesnakes sense a threat, different species have developed various ways to protect themselves. Conservation Most species are stable, but one species and one subspecies are federally listed as threatened. Fun Fact Although rattlesnakes may seem scary to people, they play a very important role in their ecosystems by controlling small mammal populations.

Donate Today. Sign a Petition. Donate Monthly. Nearby Events. All trick, no treat? The high price of harvesting cocoa for chocolate Read More. Read More. Learn More. Inquire at your local conservation commission, zoo, or at exotic pet stores about observing rattlesnakes in captivity during breeding and reproduction.

Rattlesnakes are viviparous and give birth to live young, so you will need to observe a live birth to know the exact age of a rattlesnake. Communicate your interest in observing a live birth and monitoring the age of an individual group of newborn rattlesnakes. Get any necessary permits or permission required. Request permission to continuously film the area with the pregnant rattlesnakes so there's no chance of you missing the big moment.

Set your videocamera to mark the date and time. Record when rattlesnakes are born. Isolate, mark or tag the group to distinguish them from rattlesnakes born earlier or later after obtaining permission from owners or supervisors where you are observing the rattlesnakes.

Once the rattlesnakes are tagged, if their tag or mark is recorded with the date of their birth, you can look up their date of birth in the future to tell the age of the snake.

All have been shedding over the past few weeks. Like other animals, baby snakes grow rapidly, so they must replace the corneal layer frequently to accommodate rapidly expanding bodies. Since shedding frequency is highly correlated with growth rate, juveniles usually shed several times per year. Growth rate and shedding frequency slows with size and age, with large adult rattlesnakes sometimes shedding less than once per year.

Rattle growth is a fundamental part of the shedding process for rattlesnakes. The rattle is made of keratin, the same stuff as the acellular matrix of the corneal skin layer — and your fingernails.

Each time the snake generates a new corneal layer and prepares to shed the old one, it also produces a new rattle segment. Thus the newest segment is always at the base of the tail and contains live tissue — much like the base of your fingernail. And because each new segment is the width of the tail, young rapidly-growing rattlesnakes produce a tapered rattle photo below. The rattle is made up of loose, hollow, interlocking segments. The two hidden lobes fit loosely inside the older adjacent segments photo, below.

Rattlesnakes are born with a tiny hard cap on the end of the tail. I like to use the analogy of an eraser on a pencil — which is the approximate size of the newborn snake and the cap.

During every subsequent shed, the old corneal layer will simply be an open tube that slips over the rattle. When a shedding cycle begins, formation of the new rattle segment is usually noticeable before the eyes turn blue photo, below. Injecting acrylic paint into the first hollow segment allows me to identify rattlesnakes visually, with each animal receiving a unique color combination.

The paint also allows me to record how often they shed. In Female 05 above , note that her birth button and the next two or three segments are already missing.

The location of her original paint tells us that she has shed four times in the 40 months since she was first marked. The slight taper at the end of her rattle provides a hint of her age: considering the number of segments I think are missing and that snakes grow much faster and shed more frequently when young, I estimate that I originally captured her in her third or fourth year, making her about seven years old in this photo.

Once all of the tapered segments at the end are lost, we have no way of estimating how old she is from the rattle. You can also see that the rattle segments produced by Fem 05 photo, above as a young rattlesnake are noticeably larger than the more recent thin segments.

This happens in the middle of rattles, too, with some segments being wide and robust while others are thin. I think rattle segments are a bit like tree rings in that good conditions with lots of food produce wider thicker segments. In the case of adult females like 05 above, it likely reflects the shift in resource allocation more below when she became sexually mature. It is worth mentioning that this snake had reproduced three years in a row when this photo was made and she produced the four recent thin rattle segments and her body condition was very poor after three consecutive litters.

In almost all rattlesnake species, adult males are larger than adult females. Yet the growth rate of baby males and females is indistinguishable until they reach sexual maturity. Once they start reproducing, however, female growth slows. We believe this happens because females start diverting most nutritional resources to the production of offspring, leaving much less available for their own growth.

Males, on the other hand, are free to continue devoting their resources to increased body size — which is advantageous for fending off predators while searching for females and for battling other males for access to receptive females click here for video of males fighting. The one sure thing is that each rattle segment does not represent one year.

The addition of rattle segments is well correlated with growth rate which, in turn, depends on age and food intake. We can make a pretty good estimate of age from a complete unbroken rattle and even when a few segments are missing, so long as some significant taper remains at the end. But for older snakes with broken rattles having no taper, there is just no way to know how many segments are missing.

So how long can rattlesnakes live? I have personally kept some southern California species in captivity over twenty years. We noticed that female rattlesnakes tend to hang out with one another.

Taylor has observed males and females spending time together in the time leading up to the mating season, which she thinks may be related to mate guarding. Even more surprising is that female rattlesnakes tend to hang out together when they are pregnant, and potentially give birth together.

Mother rattlesnakes look after their young for a period after their birth until their first shed. Search-Icon Created with Sketch. KQED is a proud member of. Always free. Sign In. KQED Inform. Save Article Save Article. Deep Look. Josh Cassidy. Jul 30, Failed to save article Please try again. Rattlesnakes are aggressive animals that are looking for trouble.