Question: does the barb on a stingray grow back

Answer: Yes, There are reports of stingers breaking off in wounds, but this may be rare. This would not be fatal to the stingray as it will be regrown at a rate of about 1.25 to 2 centimetres (0.49 to 0.79 in) per month (though with significant variations depending on the size of the stingray and the exact species). Contact with the stinger causes local trauma (from the cut itself), pain, swelling, and muscle cramps from the venom, and possible later infection from bacteria or fungi. Immediate injuries to humans include, but are not limited to: poisoning, punctures, severed arteries and veins, and occasionally death. Fatal stings are very rare, but can happen, infamously including Steve Irwin. In Irwin's case, the stinger penetrated his thoracic wall, causing massive trauma.