Nest Science Overview

N.E.S.T. has a long history of collecting scientific data for use in sea turtle research. Our goal is to help find out more about sea turtle behavior so that everyone can better protect sea turtles and the habitat critical to their survival. N.E.S.T. volunteers assess the location, collect valuable nest data and measurements, and evaluate the hatching success of each nest. We also collect necropsy data and samples to learn a turtle’s cause of death and assess if more can be done to protect them. In 2010 we began participation in a collaborative multi-state DNA study collecting DNA samples from each nest laid along the Outer Banks. Since 2017, we began listening at nest sites with specialized microphones for vocalizations and sounds produced by hatchlings as they emerge from their shells and work together to dig out of the sand. Data collected by N.E.S.T. has been included in numerous studies, scientific papers and graduate theses.[1]

Recently N.E.S.T. has focused on gathering additional information on our northern sea turtle nests to help researchers, nest parents and other volunteers. For example, what real life sand temperatures are too cold or too hot for sea turtles to hatch? How can we better anticipate when nests will hatch? What constitutes a lethal nest over-wash? Can we anticipate hatch times through listening to nests? Are we able to estimate the ratio of male versus female hatchlings in a nest by comparing our nest temperature data to published temperature dependent sex determination studies?

In 2017 in order to help answer these questions, N.E.S.T. initiated several new pilot projects: 1) create an extensive temperature database by placing temperature data loggers (upgraded to Bluetooth in 2018) in all nests; 2) compare nest temperature data with incubation times, hatching success and sex-ratio estimates 3) use data to help nest parents better predict when hatchlings will emerge from the nests; 4) listen with specialized microphones to nests close to hatching time to determine if the timing and duration of nest noises can alert to a hatch; 5) video some nest hatchings and excavations with an infrared camera so that visitors and volunteers can see at least some of the hatches they missed (this one is for fun!).

Volunteers excavate a successful nest to determine % of eggs that hatched and health of nest.  Photo by S. Westheiden

Volunteers confirm a nest and collect data on nest location.

[1] A few of the papers and theses that incorporate nesting and/or necropsy data collected by our volunteers include:

Avens, Larisa. Taylor, J. Christopher. Goshe, Lisa R. Jones, T. Todd. Hastings, Mervin. Use of skeletochronological analysis to estimate the age of leatherback sea turtles Dermochelys coriacea in the western North Atlantic. Endangered Species Research. Vol. 8: 165–177, 2009.
Chan, Valerie Ann. Spatial and Temporal Trends in Sea Turtle Stranding in North Carolina, 1980-2003. Masters Thesis. Nicholas School of the Environment, Duke University. Durham, NC. 2004.
Cluse WM. Boat activity and sea turtle mortality: exploring the severity of the problem in North Carolina waters. Master’s Thesis. Nicholas School of the Environment, Duke University, Durham, NC. 2002.
Cobb, Mara. Use of Caretta Caretta Nest Temperatures to Predict Hatchling Emergence. Senior Thesis. University of North Carolina Wilmington. 2020.
Goshe, LR. Avens, L. Scarf, F.S. Southwood, A.L. Estimation of age at maturation and growth of Atlantic green turtles (Chelonia mydas) using skeletochronology. Marine Biology. 57:1725–1740. 2010.
Hart, K.M. Mooreside, P. Crowder, C.B. Interpreting the spatio-temporal patterns of sea turtle strandings: Going with the flow. Biologicval Conservation Vol. 129. 283-290. 2006.
Mooreside, P.D. Integration of Physical Oceanography with Spatio-Temporal Patterns of Stranded Sea Turtles in North Carolina. Master’s Thesis. Nicholas School of the Environment, Duke University, Durham, NC. 2000.
Mrosovsky, N. Ryan, G.D. James, M.C. Leatherback turtles: The menace of plastic. Marine Pollution Bulletin. Vol. 58. 287-289. 2009.
Rush, M.D. An evaluation of nest relocation as a Loggerhead Sea Turtle (Caretta caretta) Management Technicque in North Carolina. Master’s Thesis. Nicholas School of the Environment, Duke University, Durham, NC. 2003.
Shamblin, B.M. Dodd, M.G. Bagely, D.A. et al. Genetic structure of the southeastern United States loggerhead turtle nesting aggregation: evidence of additional structure within the peninsular Florida recovery unit. Marine Biology, 158:571-587. 2001.
Snover, M.L. Hohn, A.A. Validation and interpretation of annual skeletal marks in loggerhead (Caretta caretta)and Kemp’s ridley (Lepidochelys kempii) sea turtles. Fish Bulletin. 102:682-692. 2004.