Adult stingrays provide protection for their offspring until the young reach a certain level of physical maturity, somewhere around the age of 3. From birth, however, the young stingrays find their own food, a task made much easier by the fact that they are born naturally good swimmers. Ovoviviparous, stingray give birth to fully-proportioned young, an evolutionary advantage that provides the young stingrays with a better chance at finding nourishment while getting some protection from their adult counterparts.
Stingrays are ovoviviparous, meaning they produce eggs that grow within the mother's body and then hatch either within the body or immediately after release. In fact, the biggest difference between stingrays and the closely related skate is that stingrays give birth to live young while skates lay eggs. The number of young stingrays born in this way depends on the size and age of the mother, with larger females giving birth to larger numbers of young, anywhere between one and 12. Birth tends to occur once a year.
Birth to Maturity
Newly born stingrays swim just as well as their parents, yet have little in way of natural defenses beyond their small, venomous stinging tails. As such, the mothers tend to provide some protection while the young develop, usually until the young rays reach maturity or the young rays learn to hide themselves. In the wild, stingrays tend to live between 15 and 25 years, so it takes about three years for a newly born stingray to reach maturity.
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Mother stingrays may provide protection for their young, but the young are able to swim well enough to fend for themselves in terms of finding food. As with most ovoviviparous species, the adult stingrays do not need to spend significant amounts of energy or time caring for and feeding their young. The fact that young stingrays are born fully formed, just to smaller proportions than their adult counterparts, means that they possess the necessary equipment for finding food.
In the wild, both adult and young stingrays tend to be nocturnal, hunting at night and sleeping during the day. Stingray mouths are located on the bottom of the animal, so they are bottom-feeders, swimming along the bottom and disturbing sands and mud to find invertebrates, worms and shellfish. Stingrays occasionally eat small fish, clams, shrimps and tunicates. Stingray mouths are suited primarily for crushing their food, with indigestible fragments being spit out.