Are turtles nocturnal or diurnal?
Being nocturnal is a habit that makes animals sleep during the day while being active at night. But diurnal animals possess just the opposite behavior. So to answer whether turtles are nocturnal or diurnal is not that straightforward answer; some species are nocturnal, some species are diurnal, and some diurnal species sometimes exhibit nocturnal behavior.
Most tortoises are diurnal; North American box turtles are diurnal, while their cousins Asian Box Turtles are nocturnal; species such as cooters, red-eared sliders, painted turtles are diurnal; Kinosternon (mud turtles), and Sternotherus odoratus (common musk turtles), Chelydra serpentinam, Macrochelys temminckii (alligator), Chelus fimbriatus from South America and snapping turtles are nocturnal; sea turtles are diurnal.
Though we classify some species as nocturnal and diurnal, it’s not all that clear, as we can sometimes see classically diurnal species actively foraging for their food in the night or typically nocturnal species up and happily swimming during the day. Hence, we can call Turtles and Tortoises are Cathemeral.
What is Diurnal?
Diurnal animals are active when the sun is up, meaning during the day, and sleep when the sun sets, meaning at night. Most animals are diurnal such as humans, dogs, elephants, squirrels, honeybees, deers, gorillas, etc.
What is Nocturnal?
Contrary to diurnals, nocturnal animals are awake during the night and sleep during the day. Some examples of nocturnal animals are owls, leopards, bandicoots, bats, beavers, rats, etc.
Humans love to categorize and dissect everything according to our logical mind; that is why we ask whether turtles are nocturnal or diurnal? While some animals fit in these categories neatly while others don’t; unfortunately, everything in the world is not that black and white; we continue to deny the grey area or even other colors for that matter. Well, coming to our question, are turtles nocturnal or diurnal? We forget there is something other than diurnal and nocturnal, i.e., Cathemeral.
Going by the definition of diurnal and nocturnal, our immortal pets don’t fall under either of the two categories strictly; even the species that are termed nocturnal, such as alligators, might be swimming during the day whereas, diurnal sea turtles might stay up the whole night to dig a hole to lay eggs at the shore.
Tortoises and turtles do not follow any clear pattern of activities; they switch their activities for various reasons and seasons, such as food, climate, etc.
Some turtles exhibit nocturnal behaviors to protect themselves from predation, as most predators are nocturnal. So, it is not their preference but more of a matter of survival.
Turtles in captivity, your primarily nocturnal pet turtle, can adapt to become diurnal as soon as they sense there is no danger lurking around them during the night. Moreover, they don’t need to hunt for their food as in the wild. Also, the human activity around them during the day keeps them awake.
Hence, it is more apt to call tortoises and turtles are cathemeral than either nocturnal or diurnal.
Characteristics of nocturnal animals
- Nocturnal animals prefer to stay active at night rather than during the day.
- They either have a few or no cone cells. However, they have a lot of rod cells in their retina that enables good night vision in them.
- Most of the nocturnal animals are colorblind.
- Primarily, nocturnal animals prefer to communicate by sound.
- Additionally, nocturnal animals have some extrasensory abilities such as enhanced hearing, smell, etc.
Characteristics of diurnal animals
- Unlike nocturnals, diurnals prefer to stay active during the daytime.
- They possess a lot of cone cells in their retina that serves them good daylight vision.
- Diurnals can see colors distinctly in the light.
- They use combined methods when it comes to communication, where vision plays a vital role.
The night activities of turtles
Indeed, some turtles are nocturnal, but what do they exactly do during the night hours? They keep themselves involved in various activities that make their nighttime more active than they would be in the day.
Turtle species like Mud and Musk are more active at night, foraging at the bottom of the ponds. On the other hand, common musk, alligators, snapping turtles lay their eggs during the night. Mata Turtles from South America are also highly nocturnal. So, even they stay pretty active all night long.
Though Sea turtles are diurnal, they swim to the shore during the night and dig a hole to lay eggs. Similarly, the diurnal Green Turtle exhibits nocturnal activities.
Can a turtle see in the dark?
Yes, turtles can see in the dark like us once their eyes adjust to the darkness; but their night vision cannot be tagged an excellent one. In fact, their night vision is quite similar to us humans.
Similar to us, their iris narrows and pupil constricts during the day. It enables lesser light into their eyes and makes sure that they do not get overwhelmed by the amount of light they are receiving.
So, in darkness, the pupils of the turtles’ eyes enlarge widely to allow more light. And this makes them see in the dark or when there’s a lesser amount of light. However, their eyes fail to adjust immediately when their ambiance becomes dark all of a sudden. But once adjusted, they can see pretty well in the dark. In addition, studies show that turtles can see more colors than a human can.
Why are some turtles not nocturnal?
While some turtles are nocturnal, some are not owing to several factors. Such turtles tend to stay active during day hours as most of their activity occurs at that time. Moreover, they also have certain limitations, making them relatively inactive at night.
- The turtle species that are not nocturnal lack peripheral vision, which makes their eyes take some time to adjust in darkness. However, their vision is not as clear as in the daytime, even after getting adjusted.
- For a nocturnal animal, it is crucial to possess the necessary senses that can aid in their communication and navigation in the dark.
- Most turtles, in general, cannot hear well; they lack the essential eardrum or tympanum, which prevents them from sharp hearing.
- Moreover, turtles need UVB light exposure to make their bones healthier and stronger during the daytime. So, being diurnal allows them to stay active during the day and bask under the sun, maintaining good bone health.
Hence, some species of turtles prefer to spend their life as diurnal and not being nocturnal. However, a few can adapt to both situations.
Are sea turtles nocturnal?
Are turtles nocturnal when it comes to their sea/marine species? Sea turtles are diurnal. They sleep at night by floating on the water surface or prefer tucking themselves into a coral crevice or rock.
Usually, juvenile turtles sleep on the water surface and rest with their front flippers folded back into their shell.
But the egg-laying female sea turtles come ashore during the night to make a hole in the sand to deposit their eggs to keep them safe from predators. Also, some turtle species hatch in the night and try to navigate by moving towards the brightest place.
However, Odisha Beach, India, witnessed hundreds of thousands of sea turtles nesting during the day last year. Experts concur that the daytime nesting could be because people are under lockdown, and the turtles feel comfortable nesting during the daytime.
Are Pet turtles nocturnal?
In captivity, turtles follow the routine of their masters; mostly, they sleep during the night and get active during the day like their masters. Also, it may not be a conducive atmosphere for their sleep during the day as the humans around them carry out different activities.
We should not forget that the foremost existential need of all living creatures is food; in captivity, the food supply comes when the master is awake; the master attends to all their physical and emotional needs during the day when they are awake. Automatically, the pet turtles exhibit the traits of diurnal.
As we know, turtle basks under sunlight; most turtle owners create a separate basking area for their pet to bask; some owners might even provide UVB light in the basking area for shell and bone growth and overall growth and the health of their turtle.
Are painted turtles nocturnal?
As we have seen, pet turtles sleep when their master sleeps and awake when their master is up, and painted turtles are no exception. Hence, painted turtles exhibit diurnal behavior; during the day, they dine, bask, and they are busy looking for their mates during the mating season.
Are Box turtles nocturnal?
Most box turtles are diurnal, but some species of box turtles are nocturnal, such as Asian box turtles; however, their cousins from North America are diurnal.
Does the box turtle have eyelids?
Unlike mammals, reptiles do not have eyelashes to protect their eyes. However, they have a different way to protect their eyeballs; a nictitating membrane, a third eyelid that slides horizontally from the side; this membrane is translucent allows them to see with the closed eyelids. It’s pretty helpful while swimming like us humans use pair of goggles.
Are red eared sliders nocturnal?
Red-eared sliders are diurnal; leave the water to sunbathe; hence it’s essential to have a basking area assigned for your pet red-eared. They generally sleep at the bottom or float on the surface using their inflated throat.
They are not nocturnal because they don’t have good hearing senses but have well-developed sensory touch.
Are turtles nocturnal? Parting Thoughts
Are turtles nocturnal? As we have discussed in the article, it is not a straightforward yes or no answer. It depends on species and other conditions such as the surrounding environment, water temperature, humidity, many things that influence their sleeping behavior. Hence, it is tough to say whether turtles are solely nocturnal or other reasons behind their sleeping behavior. That is why its apt to refer them as Cathemeral.
You would need to look for information on your pet’s species and accordingly do the needful. However, if you find something abnormal in their sleeping behavior, do not delay rushing to a vet.