by David F. Kramer
Turtles and tortoises are among the longest living animals in the world, much less in the reptile kingdom. A decision to own one as a pet could very well include a lengthy commitment, perhaps even as far as making allowances for your reptile friend’s care in your will. While turtle ownership will probably not need the help of your attorney, it’s bound to be a pet you’ll enjoy for years to come.
It’s common knowledge that the immense Galapagos tortoise can live to well over 100 years. The longest verified tortoise lifespan was 188 years. On average, the lifespan of a turtle is 30-40 years, with sea turtles averaging between 80-100 years; it takes about 20 to 40 years just to reach maturity and be able to breed. Box turtles and tortoises can live for 50-100 years on average.
However, the Painted Turtle, found in 45 states, southern Canada and Northern Mexico, is a uniquely hearty character, as well as a very popular pet. A staggering 99 out of 100 of this species generally survive from one year into the next and can easily live 30 years or more. But that’s not all; some scientists postulate that they could potentially survive for 300 years, though for obvious reasons this has yet to be verified.
The bulk of risks to the life of a turtle are when they are small, young, and vulnerable to natural predators. Once they reach maturity, they are far more likely to continue to survive. A turtle kept in captivity with specialized care and diet should, of course, live longer than its wild counterparts, provided that care and maintenance is taken to ensure that. Indeed, the turtle is skilled at the game of life.
Many turtle owners are undoubtedly curious as to the age of their pets. Well, here’s the bad news: Short of being present when they’re hatched, there really is no definitive way to know. There are, however, a variety of ways to approximate a turtle’s age and make some fairly educated guesses that might satisfy a pet owner’s curiosity. It’s not difficult to do, and it simply involves taking a good long look at your reptile companion, as well as its living environment.
Comparing the size of your turtle to one of the same species as an adult is good start. However, once they reach adulthood, they will stop growing as they continue to age, so this simple check is by no means certain. Keep in mind that females grow larger than males, so this will also need to be taken into account.
If your turtle was bred in captivity, you can probably shave a few years off its age as turtles tend to grow much faster when their diet is rich and they are well cared for. Turtles will only be able to breed once they reach maturity, so knowing if your turtle has ever bred can also help approximate its age. Water turtles generally reach maturity between 5 to 8 years of age, and for tortoises it can be as much as 20 years to reach full maturity.
Also, as a turtle lives, the time and elements do take their toll on a turtle’s shell and skin, even if it has spent its life in captivity. Any dent, chip, or discoloration on the shell might be symptomatic of a long life, but it could also be the result of a single tumble out of a tank, or even from the basking place of a young turtle.
Much like the rings on the trunk of a tree, a turtle develops rings in the blastron scutes (belly scales) as it ages. However, simply counting them and assuming each one represents a year would be a mistake. The rings on a turtle denote periods of growth rather than lengths of time. In some years in a turtle’s life it may grow a great deal, and in others it may grow very little, if at all. A thicker ring could indicate a growth spurt, even if this took very little time over the life of a turtle.
While rings might indicate periods of growth later in life, the markings are still relative in making guesses as to its current age. So again, it’s more than a matter of just counting rings.
Dr. Adam Denish of Rhawnhurst Animal Hospital in Pennsylvania has seen, up close and personal, just how long some turtles can survive.
“I actually have a tortoise client in my practice that has an amazing history with their family pet. They own a tortoise that was living in Queen Victoria's gardens in the 1880s in London,” he says. “They have direct provenance to account for the age of the tortoise. If you saw this amazing 52 pound animal, you would assume it was old by its shell, but never would you think it would be over 130 years old.”
According to Dr. Denish, a visit to your veterinarian can also help you to estimate the age of your pet turtle.
“By the same token, I see at least a few tortoises a month that are so badly deformed from previous disease that they look old. The conformation of the shell, the quality of the scutes, the color of the shell, and the texture of the skin and shell are all signs that allow me to guess the age of the animal,” saod Dr. Denish.
But again, even from a veterinary standpoint, that’s still just a guess.
So, is knowing your turtle’s age all that important? Dr. Denish says no.
“In truth, it only matters in a few circumstances. First, if breeding is going to be considered, it will allow you to know when the pet can be bred. Second, it helps you to know what size that turtle will be when an adult. That helps you to make sure that you have an appropriately sized enclosure for that pet. Finally, it helps in some species when you need to know the proper diet for a newborn, a juvenile, an adult, or a geriatric. To me, it is most important to research the species you are considering to make sure it is appropriate for you regarding temperament, size, care requirements, and costs.”