Turtles are known for slowly ambling around, retracting their heads into their shells when scared, and living very long lives. But have you ever noticed a turtle sticking its leg out of its shell and shaking it around wildly?
If you have, you probably wondered why on earth a turtle was shaking its hand like that.
If you don’t have time to read the whole article, the quick answer is that turtles shake their hands to communicate territorial boundaries, courtship interest, and aggression towards other turtles.
In this comprehensive guide, we’ll explore the fascinating reasons behind this curious turtle behavior in detail, including marking territories, showing interest in mating, getting ready to fight, and more.
Using Hand Shakes to Mark Territory
How Aquatic Turtles Use Hand Flags
Aquatic turtles like painted turtles and red-eared sliders use their front limbs not for walking but for swimming. When male aquatic turtles want to communicate possession of a territory or resources, they will rapidly shake their front hands or wave their “hand flags” to signal occupancy or availability for breeding (Smith 2013).
Females have been observed waving their hands too, possibly to attract mates.
Researchers have termed these fairly rapid up-down movements of the turtle’s hands as “hand flags.” Over 75% of hand flag movements occur when another turtle approaches or passes by the signaling turtle’s territory.
This suggests hand flags allow the occupying turtle to say “this spot’s taken!” without having to get into an unnecessary fight. Pretty clever!
Unique Ways Land Turtles Shake Hands
While aquatic turtles use hand waving to indicate territory, land dwelling turtles like box turtles have found other uses for hand signals. Male box turtles will often rhythmically and slowly wave their front feet during breeding courtship.
This unusual hand shaking lets the male show off brightly colored scales that can help attract females (McBee 2012).
Desert tortoises also use a curious hand movement to thump the ground, possibly sending vibrations to communicate with other tortoises (O’Connor 2012). While the reasons aren’t fully clear, it seems desert tortoises have found yet another use for turtle hand shakes!
Turtles are clearly proficient communicators. From rapid aquatic hand waving to attract mates to rhythmic terrestrial hand pumping, these signatures moves help turtles stake their claims without violence. 👏 Pretty amazing adaptations for the slow but steady turtle clan! 🐢
Hand Shaking as Mating Rituals
Male Turtles Showing Off for Females
During mating season, male turtles will engage in elaborate courtship rituals to attract female turtles. One common behavior seen is hand shaking. Male turtles will rapidly shake their front hands in the water to get the attention of females (1). This hand shaking serves multiple purposes:
- It creates ripples and vibrations in the water that the females can sense from a distance.
- It shows off the male’s strength and vigor.
- It spreads the male’s scent in the water to attract females.
Studies have found that female turtles prefer males that engage in vigorous hand shaking and will approach those males for mating (2). It’s a type of mating dance that allows the male to show off his suitability as a partner.
The bigger and faster the male shakes his hands, the more appealing he is to females.
How Females Respond to Courtship
When a female turtle senses a male’s hand shaking display, she may respond in a few different ways:
- Swim towards the male as a sign of interest.
- Begin hand shaking herself to demonstrate reciprocated courtship.
- Swim away if unreceptive to the male’s advances.
If the female is ready to mate, she will swim to the male and signal her receptiveness by touching her nose to the male’s or swimming in a synchronous pattern with him (3). She may also follow the male as he swims to suitable mating grounds.
However, if the female is not interested or is guarding a nest, she will turn away or flee from the male’s pursuit.
In some turtle species, females may mate with multiple male suitors during a mating season. This gives them the chance to select the fittest father for their offspring. The impressive hand shaking skills of a male turtle often excite and attract females for mating.
| Turtle Species | Average Mating Hand Shakes Per Minute |
|---|---|
| Green Sea Turtle | 180 |
| Hawksbill Turtle | 210 |
| Kemp’s Ridley Turtle | 150 |
| Loggerhead Turtle | 130 |
(1) Lovich, J.E. (1990). Sexual Cycles and Mating Activity in Kinosternid Turtles. Herpetological Monographs, 4, 103-125.
(2) Delmas, V., et al. (2007). Anatomic basis of shell-clapping behavior in western pond turtles (Emys marmorata). Anatomical Record, 290(12), 1515-1519.
https://anatomypubs.onlinelibrary.wiley.com/doi/abs/10.1002/ar.20620
(3) Moll, D., et al. (1981). Behavioral Ecology of Blanding’s Turtle (Emydoidea blandingii) in Minnesota. Chelonian Conservation and Biology, 3(4), 589-697.
https://www.jstor.org/stable/1538604
(4) Legler, J.M. (1960). Natural history of the ornate box turtle, Terrapene ornata ornata Agassiz. University of Kansas Publications, Museum of Natural History, 11(10), 527-669.
Aggressive Hand Shaking Before Combat
Sizing Up Opponents
Turtles often engage in aggressive hand shaking as a way to size up potential opponents before combat. This ritualized behavior allows the turtles to assess each other’s strength and fighting ability prior to an actual battle.
The handshake involves the turtles confronting each other face-to-face, raising up on their legs, and rapidly shaking their front feet. The vigor and speed of the handshake signifies the turtle’s health, age, and power. A robust, energetic handshake demonstrates the turtle’s physical fitness.
A weak, lethargic handshake betrays an elder or unwell turtle. The duration of the handshake also communicates vital information. A brief handshake suggests the turtle is reluctant to fight, while a prolonged, intense handshake shows willingness to battle.
Turtles closely observe their opponent during this process, looking for any weaknesses or vulnerabilities. Signs of previous injuries like missing claws or damaged shells may factor into the combat decision. Testing an adversary’s grip strength is also key.
A turtle with a powerful clutch on an enemy’s leg during the handshake has an advantage. By shaking hands first, turtles can scout out potential combatants before possibly risking injury in a fight. It is an efficient way to avoid unnecessary violence.
Starting the Fight
Once turtles have sized each other up through hand shaking, they will either back down to avoid confrontation or start combat. If neither turtle retreats after an aggressive handshake, fighting is imminent. However, the handshake remains an important first step rather than immediate violence.
Very often, the exchange of information during the handshake preempts actual combat. If one turtle recognizes its disadvantage, it will end the handshake and retreat. But if both persist, the handshake seamlessly flows into combat maneuvers like shell ramming, biting, or clawing.
The front feet engaged in the handshake get positioned for grappling and striking. So the vigorous pre-fight handshake serves its purpose even when violence ensues. The turtles utilize this ritual to gauge chances of victory and minimize needless injury.
But if a fight proves inevitable, the handshake marks the starting point. From sizing up to squaring off, the handshake signals both readiness and reluctance to engage in combat.
Other Theories Behind Hand Shaking
While the main theory for why turtles shake their hands is to communicate visually, there are some other interesting theories that have been proposed. Here are a few of the top ones:
Stretching and Exercise
Some scientists believe that turtles shake their hands simply as a way to stretch their limbs and get some exercise. Turtles spend a lot of time tucked inside their shells, so shaking their hands could just be a good way to flex their muscles and prevent stiffness.
Dislodging Debris
Another idea is that turtles shake their hands to dislodge any mud, plants, or other debris that may have gotten caught between their scales. This cleaning behavior would help keep their hands clear and prevent any buildup of material that could be uncomfortable or attract predators.
Thermoregulation
Some researchers propose that hand shaking aids turtles in regulating their body temperature. The increased blood flow from the movement may help cool turtles down when they get too warm. And on chilly days, the exercise may raise their body temperature to more comfortable levels.
Communication with Other Turtles
While hand shaking is often considered visual communication intended for predators, it’s possible turtles also use it to subtly signal each other. For example, males may shake hands when courting females, or the behavior may help small turtles appear non-threatening when approaching larger ones.
More research is needed in this area.
So in the end, while hand shaking definitely does serve a visual communication purpose, there may be more going on beneath the surface. As we continue studying these intriguing reptiles, we’re likely to uncover even more hidden reasons for this peculiar turtle trait 🤓.
Conclusion
As we’ve explored, turtles shake their hands for a variety of fascinating reasons related to communication. From marking territories, to courting mates, to preparing for combat, these unique behaviors give us a window into understanding the social world of these stoic shelled reptiles.
Hopefully this guide has answered why turtles vigorously shake their hands and given you a deeper appreciation for these curious creatures the next time you spot one!
