Editor’s note: The Ocracoke Preservation Society has a wonderful shell collection. For details from an earlier story, click here.
By Peter Vankevich
One access road to the Pamlico Sound on Ocracoke that doesn’t require an ORV permit is Devil Shoals Road. This roughly half a mile road is located across from the campground and adjacent to the Hammock Hills nature trail.
Unless necessary, this is a road to walk rather than drive. From spring into fall, one can see and hear several interesting bird species: Gray Catbirds, House and Carolina Wrens, Prairie Warblers, Common Yellowthroats, Eastern Towhee, Brown Thrasher and, as you approach the marsh, Clapper Rails. It’s also a hot spot to see small fiddler crabs.
This spring, the road was resurfaced to provide better access for non-4WD vehicles. The material consists of groundup seashells, but these aren’t your typical shells. Some of these are prehistoric. Many along the sides of the road were fully or near fully intact. Although the intact shells are now mostly gone, there are still broken up remnants that can challenge identification.
Dr. Doug Wolfe, the N.C. Shell Club’s historian, had an opportunity to walk the road during the club’s annual visit to Ocracoke and Portsmouth islands in March.
Calling it “conchological sleuthing,” he marveled at the many species non-native to North Carolina, including at least 30 fossil species and hypothesized there were two distinct and distant locations whence these shells originated.
The road closest to the entrance was paved mainly with ocean quahog shells. In North America, this species ranges from Greenland to Cape Hatteras, and is harvested commercially off the coasts of New England, New Jersey and Delaware. Because ocean quahogs are one of the longest-lived (300 to 500 years) mollusks known to science, Wolfe said their catch must be carefully monitored and regulated to prevent serious population decline.
Mixed in with the ocean quahog shells were small numbers of other species that would have been incidental by-catch in the commercial fishery: Northern moon snail, northern whelk and New England Neptune. Some of these species still contained the rotting snail, indicating that the material had been obtained within the past month or two from a commercial facility that had shucked the ocean quahogs. Atlantic deep-sea scallops were present in small numbers, probably also as incidental by-catch.
Farther in from the highway, the sides of the road got more interesting as there were many Pliocene fossils, including extinct vase and left-handed cone shells that lived 1.8 to 6 million years ago. Among these fossils were several species ancestral to the modern Florida fighting conch, apple murex, olives and spiny jewel box that occur off Cape Lookout.
Another beautiful fossil gastropod he found on the road edge is the extinct species Pleioptygma carolinensis, originally (1840) described as a volute, later considered to be in the family of miters, and now assigned to the recently (1989) named subfamily Pleioptygmatinae, which is represented by a single living species found in the Caribbean off Honduras.
He speculated that the fossilized shells came from commercial marl pits near Sarasota, Fla., which is the only location in which he has seen them. Marl is a calcium carbonate or lime-rich mud which contains variable amounts of clays and silt.
Why, he wondered, would someone haul these all the way from Florida rather than from a North Carolina marl pit in Carteret County or near New Bern or Wilmington?
Mike Barber, spokesperson for the Cape Hatteras National Seashore, said since the shells came from a contracted commercial source, he was unable to provide exact origins, except to confirm Wolfe’s thesis–the shells were indeed brought in from Delaware and Florida.
Those interested in the shells of Ocracoke should be aware that unusual shells found along a road, as in this case, do not necessarily show up from a major storm.