Reproduction, Parenting, and Social Lives of Stingrays

A deeper look at a stingray’s family life

How Do Stingrays Reproduce?

Stingrays, like their close relatives the sharks, use internal fertilization. Males possess claspers—modified pelvic fins—used to transfer sperm to the female. Copulation can be rough; males often bite the female’s fins to hold on during mating, leading to observable bite marks and even thicker skin in females as a protective adaptation. Their cloaca handles both reproduction and excretion [1].

Most stingray species are ovoviviparous, meaning embryos develop inside eggs that remain within the mother's body until they hatch. The young are born live, having been nourished first by yolk and later by a nutrient-rich uterine secretion called histotroph or "uterine milk" [2]. This reduces predation risk during early development, giving newborns a head start in life.

Do Stingrays Care for Their Young?

Despite this maternal investment during gestation, most species of stingrays do not exhibit postnatal parental care. Once born, the pups—miniature replicas of adults—are fully functional and independent. Some species, like the giant freshwater stingray (Urogymnus polylepis), may stay near the mother for a short time post-birth, but this behavior is not well understood and isn’t seen as active parenting [3].

Stingray pups can begin feeding themselves immediately, using their specialized stingray teeth to crush prey like mollusks and crustaceans [4].

Do Stingrays Have Social Lives?

Stingrays are generally considered solitary animals. For much of the year, individuals lead independent lives, burying themselves in sediment to ambush prey or avoid predators. However, certain species like the round stingray (Urobatis halleri) do make seasonal groups, especially during mating seasons. These gatherings may be driven by environmental cues like water temperature or the presence of estuarine habitats [5].  If you notice an abnormally large number of stingrays, it may be that you've caught one of these groups -- exercise more caution than usual, to avoid getting stung. In California, Seal Beach is especially known for its large population of stingrays, earning it the nickname “Ray Bay”. If you're curious to learn more about other stingray hotspots, checkout our post about where and when you are most likely to get stung.

While some aspects of stingray mating are well understood, others are still mysterious. Scientists know that male stingrays will bite female stingray’s fins during mating. However, mating only occurs when a specific portion of the female’s fins are bitten, and male stingrays sometimes bite other portions of the female. Scientists are unsure why this other biting behavior happens, but it could be that the stingrays exchange other information during these non-mating bites [6].

Do Stingrays Communicate or Play?

It was previously believed that stingrays do not produce sounds, but recent data has put this in question. Scientists have observed and recorded stingrays making noise when they are approached. Additionally, the sounds produced are within the frequency range that Elasmobranchs (which include both sharks and stingrays) can hear! They suspect that the sounds are intended to startle sharks or other predators away [7].

Stingrays likely communicate with each other primarily through body language, touch, and possibly electrical signals. During mating, tactile cues such as biting and fin contact are essential [6]. Researchers have conducted experiments replicating the electric field generated by a stingray, and found that other stingrays seem to respond to the generated signal. They suspect that this helps stingrays detect each other during mating [8].

Stingrays and Human Interaction

Stingrays typically use their stingray barb only in self-defense, but accidental injuries can happen when people step on stingrays. These stingray barb injuries can be extremely painful due to the stingray venom, although they are rarely fatal [9]. Even so, it’s common for people to worry “can a stingray kill you?”. While the pain from a stingray sting is intense, the real danger lies in the wound itself, not the venom [10]. The stingray barb can sometimes break off in the wound, making the wound much worse than it would otherwise be , or even requiring surgery to remove the barb. Additionally, the wound exposes the injury to lots of unfamiliar bacteria, which can lead to infection and sometimes sepsis. Here's a post where you can read more about how best to treat a stingray sting.

The best ways to prevent an unwanted stingray sting are to practice the stingray shuffle when entering shallow water, pay attention to beach warning signs and beach flags (purple flags indicate dangerous marine life like stingrays), and wear protective gear like DragonSkin stingray resistant booties

Footnotes

[1] Nordell, S.E. Observations of the mating behavior and dentition of the round stingray,Urolophus halleri . Environ Biol Fish 39, 219–229 (1994). https://doi.org/10.1007/BF00005124

[2] https://en.wikipedia.org/wiki/Urolophidae

[3] https://en.wikipedia.org/wiki/Stingray

[4] Gilliam, D. S., & Sullivan, K. M. (1993). Diet and Feeding Habits of the Southern Stingray Dasyatis americana in the Central Bahamas. Bulletin of Marine Science, 52(3), 1007-1013.

[5] Vaudo, Jeremy & Lowe, Christopher. (2006). Movement patterns of the round stingray Urobatis halleri(Cooper) near a thermal outfall. Journal of Fish Biology. 68. 1756 - 1766. 10.1111/j.0022-1112.2006.01054.x. 

[6] Nordell, S.E. Observations of the mating behavior and dentition of the round stingray,Urolophus halleri . Environ Biol Fish 39, 219–229 (1994). https://doi.org/10.1007/BF00005124

[7] Fetterplace, L. C., Esteban, J. J. D., Pini‐Fitzsimmons, J., Gaskell, J., & Wueringer, B. E. (2022). Evidence of sound production in wild stingrays. Ecology, 103(11), e3812.

[8] Tricasa, Timothy C.; Michael, Scott W.; Sisneros, Joseph A. (December 1995). "Electrosensory optimization to conspecific phasic signals for mating". Neuroscience Letters. 202 (1–2): 129–132. doi:10.1016/0304-3940(95)12230-3. PMID 8787848.

[9] https://www.poison.org/articles/how-to-prevent-and-treat-stingray-injuries-201

[10] https://animals.howstuffworks.com/fish/stingray.htm