Few people have been lucky enough to encounter a school of mobula rays. Using their wing-like fins to propel themselves out of the water, the small rays breach and bellyflop, looking something like flying tortillas as they cruise through the world's oceans.
Using an aerial drone, zoologist and wildlife photographer Mark Carwardine managed to capture this rare footage when a school of rays gathered in the hundreds off the east coast of Baja, Mexico.
Mobula rays can propel themselves to heights of more than two metres (6.5ft), often remaining airborne for several seconds before splashing back down. "I spend every winter running whale-watching trips in Baja California, Mexico – it’s one of my favourite places on the planet," Carwardine wrote on YouTube. "And [this was] something quite extraordinary."
The rays feed on plankton and small fish, so surface waters offer particularly good pickings. Those horn-like protrusions on the front of the head are known as cephalic fins – you've probably seen them before on the closely related manta ray – and they assist in feeding by funnelling food to the mouth.
Many possible explanations have been put forward to explain the rays' acrobatic displays. The behaviour might be linked to everything from hunting and courting to parasite removal. Scientists also believe the breaching acts as a form of communication, both within the same school and with neighbouring rays.
Summoning other rays to the table might mean sharing resources, but it could also allow for a broader choice of mates and better odds against predators. Of course, it's also possible that these fish are just having a bit of fun.
Like their shark cousins, these so-called "devil rays" take many years to reach maturity, making them especially sensitive to fishing pressure. The gestation period is long, lasting about 25 months, and results in only one, possibly two, pups born in summer. And because the rays follow schools of fish, bycatch in drift gill nets can seriously affect local stocks.
There is still a lot to be learned about these elusive aerialists, but footage like this can help us better understand their movements and behaviour – and that's critical information for experts who are working to protect them.
Human Impact
Human Impact
Oceans
