Pelagornis sandersi, the Largest Flying Sea Bird

Move over, Big Bird. There’s a new feathered giant in town, and this one can actually fly.

Well, it could fly when it was alive. Pelagornis sandersi (Pelagornis S. for short) has been dead for about 25 million years, but we only just identified its remains [PDF].

Fossilized bones from this giant sea bird were originally discovered in South Carolina in 1983 when workers were excavating to create a new terminal for the Charleston International Airport (during the bird’s life, Charleston would have been submerged under 33 feet of water). But the bird wasn’t studied until recently when Dr. Daniel Ksepka, the Curator of Science at the Bruce Museum in Greenwich, Conn., got his hands on it.

"This is pushing the boundary of what we know about avian size,” Ksepka said, “and I'm very confident that the wingspan is the largest we've seen in a bird capable of flight."

How large? Pelagornis S. could spread its wings to span about 24 feet. For reference, that’s the width of an official FIFA soccer goal from pole to pole. It belongs to a family of seabirds called Pelagornithids, which lived all over the world and only became extinct about three million years ago. These birds were characterized by the bony teeth on the outside of their beaks, which they used to impale their prey—probably sea snacks like eels and squid.

But this bird weighed close to 50 pounds. How did it take flight? Researchers think it had to get a good, long running start like a hang glider. Once aloft, its long, slender wings prevented drag and helped it ride wind currents for extended periods of time without needing to expel energy by flapping. "I think they just waited on the beach for a strong wind to carry them aloft," Ksepka said.

The previous record holder for longest wingspan—23 feet wide—belonged to the extinct Argentavis magnificens. This bird also had to get a running start because it was too heavy to take flight from a standstill. Today, the title goes to the royal albatross, which spans just 11.5 feet.

Researchers aren’t sure what killed the Pelagornithids, but they hope to find out. “Pelagornithids were like creatures out of a fantasy novel—there is simply nothing like them around today,” Ksepka said [PDF].