Seven-year-old Aidan Isenstadt likes to collect stuff. He likes looking for bugs, mostly, and different kinds of rocks and coins.

Last month, he and scores of others tried their hands at looking for dinosaur fossils at the Dinosaur Park in Laurel. And barely five minutes after he began his search, Aidan found what looked like a piece of a jawbone, about 11/2 inches long, with holes where the teeth should be.

"First, I showed it to my dad, then to one of the people who worked there," he said. His dad, Bill Isenstadt of Elkridge, was surprised.

So was Dave Hacker, an amateur paleontologist and a volunteer at the park.

"I was gushing," Hacker said. "I knew what it was immediately, and I knew it was something we had never found out there before, and I said so."

Matthew Carrano, the curator of dinosaurs at the Smithsonian Institution's National Museum of Natural History, saw the fossil a few weeks later.

"It's part of the lower jaw of a meat-eating dinosaur, a predatory dinosaur," he said. "It's small, but the texture of the bone is very grainy, almost like wood, which is very common in juvenile dinosaurs."

He said meat-eaters in the region at the time ranged from 5-foot-long raptors to 30-foot giants. As for Aidan's dinosaur, Carrano said, "my hunch is, it's more likely one of these smaller-sized animals. … Its whole head would have been about 8 inches long."

Aidan's find ranks as the first jawbone from a meat-eating dinosaur ever found in Maryland, and the first from the Early Cretaceous period anywhere in the Eastern United States.

Immediately after Aidan found his fossil, Hacker and Peter Kranz, president of the Dinosaur Fund, which runs the park's programs for the Maryland National Capital Parks and Planning Commission, roped off the area. That was to protect any more jaw fragments that might lie there until a careful search could be organized. Two more fragments were found, one of which fit Aidan's perfectly.

The remains appear to date from about 116 million years ago, Carrano said, a time when what is now the Route 1 corridor in Maryland was part of a coastal bayou. For more than a century, the deposit exposed at Dinosaur Park has been yielding fragmentary remains of dinosaurs, turtles, crocodiles, snails, mussels and pine cones.

And the discovery rate has increased sharply since the park opened to the public last October.

Almost as soon as they opened the gates, 9-year-old Gabrielle Block, of Annandale, turned up a dinosaur tailbone. Since then, the park has attracted more than 2,500 visitors, who have found dinosaur and crocodile teeth, a partial dinosaur limb bone, turtle shell fragments and more. All have gone to the Smithsonian Institution.

"It's been just a few months," Carrano said, "and already they've found things that are new. It's exciting, because this is going to go on for years and years. I think it's going to be a treasure trove."

Further study and cleaning of Aidan's fossil could reveal more about the animal, and perhaps lead to a more precise identification of the species.

"There might be more clues in there," Carrano said. "There might be a tooth or two in some of the sockets. Some work remains to be done to be more specific."

Aidan Isenstadt likes any sort of dinosaur. He's liked them "maybe since I was three." Big and scary as they are, he said, "I know that now they're just bones … They can't hurt us or anything."

And for as long as the Smithsonian Institution keeps this bit of dinosaur jawbone, Carrano said, Aidan's name will be listed in the museum's catalog as its discoverer.

Dinosaur Park is open to the public on the first and third Saturdays of every month, from noon to 4 p.m. It's located in the 13200 block of Mid-Atlantic Boulevard, off Contee Road west of Rte 1 in Laurel. For information, call 301-627-1286.

frank.roylance@baltsun.com

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Maryland weather blog: Frank Roylance on meteorology

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