SLOAN, N.J.B.; Florida Institute of Technology: Burial Tolerances of Reef-Building Sabellariid Worms from the East Coast of Florida

Worm reefs run parallel to shore on the central east coast of Florida from Cape Canaveral to Miami. These rock reefs are a complex, multifaceted habitat. Sabellariid worms serve as foundation species for worm reefs. These reefs can change the local geology by stabilizing sands and providing a natural block to wave energy for coastal beaches. Little is known about the ability of Sabellariid worms to deal with burial. This study was to determine duration and depth of burial that can be tolerated by the Sabellariid worm, Phragmatopoma lapidosa. Worm rock samples were buried at depths of 1 cm intervals between 1-10 cm, and at 15 cm, 25 cm and 40 cm for the duration of 72 hours, 144 hours and 216 hours to determine if depth of burial and/or time of burial affected the mortality of P. lapidosa. One week after samples were unburied, worms were recounted to determine delayed effects, which are defined as a change in the number of living worms either due to an increase in mortality or a decrease in perceived mortality due to dormancy during burial. Mean mortality was found to be significantly different between time and depth, with mortality increasing with both greater duration and greater depth. Delayed effects found an increase in mean mortality rates by greater than 30%. P. lapidosa showed some adaptability to burial by vertically extending their tubes. By extending their tubes, worm samples at lower burial depths were able to build out of the sand. This building not only decreased their mortality but that of those worms around them. Worm rock samples in deep sediments or for longer time treatments showed a blackening of their tubes and a sulfide smell due to anoxic conditions created by the input of organic material.