Physical Effects of Beach Nourishment on Sea Turtle Nesting, Delray Beach, Florida. Environmental Impact Research Program.
Abstract
A large percentage of all sea turtle nests in the United States are located in beaches that have been nourished or renourished. Questions have been raised about how physical changes in the beaches will affect the nesting activities of these sea turtles that use nourished beaches for nesting. Delray Beach had a harder consistency from both previous nourishments and the 1984 renourishment. The cause of the harder consistency is unclear. However, finer grain size, layering of sand grains, the cohesion of silt-clay particles, equipment operation on the beach, and weight of the sand-water slurry from the hydraulic pumping are probable contributors to a harder consistency. Effects of nourishment on nesting loggerhead turtles include: (1) eggs and hatchlings were not affected negatively by the nourished sand; (2) nest depth and frequency of false digs may be affected by the harder consistency, but this effect was not evident in this study; (3) nest shape and nest digging time may be affected by sand consistency; (4) the number of nests per emergence appears to have declined following the nourishment; (5) aragonite sand may negatively affect piping hatchlings; and (6) a scrap formed at Delray Beach and will form at most beaches. The scrap may block some turtles from nesting, while some may scale the scarp, particularly if the scarp is sloped.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1987
- Accession Number
- ADA189051
Entities
People
- David A. Nelson
- John Fletemeyer
- Karen Mauck