Gervais' beaked whales are easily one of the most elusive mammals to swim through our oceans. Most of the information we have about them comes from studies of corpses that have washed ashore, and the first live whale was only spotted about 20 years ago.

On February 27, photographer and videographer Patrick Dykstra captured what may be the first drone or aerial footage of Gervais' beaked whales. He was filming about three miles off the west coast of Dominica in the Caribbean Sea. Dykstra and his Picture Adventure Expeditions team accidentally came across the rare beaked whales when they were filming sperm whales for an upcoming production.

Autopsies from Gervais' beaked whale corpses tell us that the animals eat cephalopods, so Dykstra says the whales were probably drawn to squid that the sperm whales in the area were feeding on.

"We thought we saw dolphins at first," Dykstra says. "[Gervais' beaked whales are] certainly not something you expect to see. There's been less than 10 live sightings anywhere in the world, ever."

After taking a closer look at the drone footage, Dykstra and his team saw they had filmed a family, with two males, one female, and a calf. They brought their footage to Polish beaked whale expert Wojtek Bachara and Antonio Mignucci, an oceanographer and founder of the Caribbean Stranding Network conservation database, who confirmed the sighting.

"Although it's not much, it's a new window in the lives of an incredibly rare species," Dykstra told National Geographic via email.

Whale, What Do We Have Here?

This isn't the first time Dykstra has filmed rare whales. In October, he captured footage of elusive blue whales, the largest animals on our planet, possibly making a heat run for a potential mate. But Gervais' beaked whales are even harder to catch on film, and this footage is a National Geographic exclusive.

The species wasn't documented until a specimen was found floating in the English Channel in 1840. Other footage of the whales comes from shaky cell phone cameras, but Dykstra's could be the first professional footage out there.

Watch: 'Flirting' Blue Whales Caught on Camera

"I don't know of anybody who has Gervais' [unmanned] aerial footage right now," says Dee Allen, research program officer at the Maryland-based Marine Mammal Commission. "They're really fascinating animals to follow because they're such a challenge to find."

From a distance, Gervais' beaked whales can sometimes be confused with the 21 other species of beaked whale. Gervais' beaked whales have a slightly bulging forehead and a pronounced, narrow beak. Their coloring is dark gray or bluish-black, with pale gray undersides and a belly marked with irregular white blotches. The whales weigh about 2,640 pounds and can stretch 15 to 17 feet long. Their lifespan is 27 years, but some research has shown they might be able to live up to 48. (Related: "Mysterious New Whale Species Discovered in Alaska")

Allen says the main identifier for Gervais' beaked whales is the location of their two white teeth. Mature males of the genus Mesoplodon have a single pair of front teeth in their lower jaw that erupt as they age. These teeth can be seen in males when their mouths are closed, but they are hidden in females. One of the males also has a few scars, which Allen says are likely the result of encounters with other competing males. (Related: "Do Beaked Whales Have Internal Antlers?")

"The real key in narrowing down the species here is the size, shape, and location of the teeth in the lower jaw," Allen told National Geographic via email after viewing the footage. "Aerial images such as these, both from manned aircraft and drones, can give us a new perspective on the lives of these whales."

Just Keep Swimming

When they're swimming, beaked whales tightly tuck their flippers in to their spindle-shaped bodies. They are deep divers, capable of plunging thousands of feet below the ocean's surface into the cold darkness. They can hold their breath down there under pressures that would crush the lungs and cut off oxygen in humans and shallow-water whales. These dives can last an hour or longer, and the whales make them several times each day to hunt for food. (Related: "Do Whales Get the Bends?")

"They're only at the surface for such a short amount of time," Allen says. "They're functioning in this extreme environment and they're managing to survive, which is pretty amazing."

Despite their hardiness, Gervais' beaked whales may be threatened, since information on them is so scarce. They have accidentally been taken as bycatch in fishing gear, like pound nets, driftnets, and gillnets, and they may be sensitive to increasing noise pollution. Like other marine species, Gervais' beaked whales are threatened by the warming waters and other side effects that come along with climate change. (Read: "Climate Change Is Suffocating Large Parts of the Ocean")