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Atlantic Oyster Drill

Urosalpinx cinerea

The Atlantic oyster drill is a small snail with a pointed, ribbed shell. (The Southeastern Regional Taxonomic Center, South Carolina Department of Natural Resources)
The Atlantic oyster drill is a small snail with a pointed, ribbed shell. (The Southeastern Regional Taxonomic Center, South Carolina Department of Natural Resources)

The Atlantic oyster drill is a small, predatory snail with a pointed, ribbed shell. It lives on reefs, rocks and pilings throughout the middle and lower Chesapeake Bay.

Appearance:

  • Oval-shaped shell with a pointed spire (tip)
  • Varies in color from gray or purplish to tan or yellowish-white
  • 5-6 raised whorls
  • Brown, spiraling vertical ribs
  • Thin, flared lip with small teeth
  • Grows to about 1 inch long

Habitat:

  • Lives on oyster reefs, rocks, pilings and bay grass beds in shallow waters

Range:

  • Found year-round in the middle to lower Chesapeake Bay
  • Cannot survive in the upper Bay’s low-salinity waters

Feeding:

  • Feeds mainly on oysters, but will also eat barnacles, mussels and other small mollusks
  • Secretes an enzyme to soften an oyster’s shell, then drills pin-sized holes through the shell to reach the oyster’s soft parts inside.

Reproduction and Life Cycle:

  • Spawns throughout the summer
  • Lays distinctive leathery, vase-shaped eggs that attach to a hard surface
  • Larvae crawl from the eggs within 6-8 weeks

Other Facts:

  • A significant oyster predator, particularly in parts of the lower Bay
  • Oyster drills are gastropods, a type of mollusk that includes whelks, snails and slugs

Sources and Additional Information:




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