The mating frenzy 'makes them almost blind to the exterior world,' she adds, making them vulnerable to threats, such as tourism, fishing, and boat traffic. Piggyback leaping leaves a rash on the female’s back, Palacios says-a finding that future researchers may be able to use to determine whether a female is sexually mature.įirst, however, Venables points out that researchers must be able to distinguish these rashes from other abrasions-and understand how long they last on the body-before they can be effectively used as a sign of maturity.ĭevil rays, which are incredibly shy, typically don’t tend to approach humans, and can be easily frightened away.īut, during this encounter, 'the animals didn't care about presence, they were even bumping into them,' says Palacios. It was previously believed that males need to bite a female's pectoral fin before trying to copulate, but that wasn't seen here. ( You think dating is hard? Try being one of these animals.) 'Imagine you're just swimming at the surface and someone jumps on you from behind again, and again, and again,' says Palacios.

This happened to one female over 135 times.

The study also describes another new behavior, called piggyback leaping, when the male leading the chase in a courtship train leaps on top of the female, lifts his tail, and starts rapidly thrusting his clasper, or reproductive organ. Video ByShawn Heinrichs Piggyback leaping These abrasions are a result of a pre-mating behavior called “piggyback leaping,” in which a male jumps on top of a female that he's pursuing. Small abrasions visible on the backs of these Munk’s devil rays are a new indicator of courtship activity for this species. “We know so little about mobula rays,” says Stephanie Venables, senior scientist from Marine Megafauna Foundation, who was not involved in the study: “Reproductive behavior is one of the most important aspects of their life history to understand so these findings will be really important for protection.”

This behavior gives the rays a faster way to select a mate, explains Palacios: 'If you're in a courtship train, you need to chase the same female for hours or even days'-but in the vortex males can choose their best match from 30 or 40 females. ( See a rare view of a manta ray courtship train deep in the sea.) The researchers also saw courtship trains-when male mobula rays chase a female to try to mate with her-weaving in and out of the larger vortex. The circling motion was more relaxed: the rays were touching each other, and they weren't unfurling their cephalic fins-the horn-like appendages in front of their face-to eat. Mobulas are known to create vortex formations when feeding or resting, but this is the first time vortexes have been reported in a mating context. Palacios, co-founder of Mobula Conservation, whose study examines courtship and mating behaviors in three mobula species: spinetail, bentfin, and munk’s devil rays.

'It's amazing to see a vortex of mobulas,' says Marta D. New drone footage shows 122 individuals taking part in this five-hour display in Mexico’s Baja California, with different mating groups joining and leaving the main formation over time. This is a “courtship vortex”: a previously undescribed behavior among munk’s devil rays ( Mobula munkiana) that has now been captured on film in a study conducted by the conservation nonprofit Manta Trust. Beneath the waves, a tornado of hundreds of devil rays swirl in a dizzying dance that goes on for hours. Splashes at the surface give an indication of the commotion below.

Manta ray bite