Abstract:
A network of volunteers, under the guidance of the North Carolina Sea Turtle Protection
Program, monitors and protects loggerhead nests laid on state beaches. Although volunteers are
encouraged to allow nest incubation to proceed naturally and with minimal intervention, some
volunteers will relocate freshly laid nests that are threatened by possible inundation by high
tides, heavy beach traffic, or under a sloughing escarpment.
Nest relocation may have negative effects: it may reduce hatching success, alter incubation
duration, and reduce hatchling fitness. Thus an evaluation of hatching success and incubation
duration at nesting areas under the protection of the NC Sea Turtle Protection Program is
warranted.
My objective for the evaluation was to use loggerhead sea turtle (Caretta caretta) nest activity
data from four high-density North Carolina nesting areas – Bald Head Island, Cape Lookout
National Seashore, Cape Hatteras National Seashore, and Topsail Island – to assess statistically
the management technique of nest relocation in North Carolina. Using 1997 to 2001 data,
provided by the North Carolina Sea Turtle Protection Program, I evaluated hatching success and
incubation duration among in-situ nests, relocated nests, and in-situ nests affected by tidal
inundation.
During each of the five years, 1997 to 2001, the average number of nests moved on the study’s
four North Carolina nesting areas approached 40 to 60 percent. The evaluation of hatching
success showed a tendency of more loggerhead hatchlings hatching in in-situ nests than in
relocated nests. Also, the evaluation indicated a tendency of in-situ nests having longer
incubation durations than relocated nests.
The evaluation showed relocated nests might have shorter incubation periods, and thus present
nest relocation techniques in North Carolina might be skewing northern sub-population sexratios
more in favor of female hatchling production.
I formulated a series of nest relocation recommendations with the evaluation results: use nest
relocation as a last resort, only relocate nests that will be over-washed daily by high tides, do not
base nest relocation measures on previous summer storms, and do not relocate nests in heavy
foot traffic areas.
