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Egg turning behavior and incubation temperature in Forster’s terns in relation to mercury contamination

February 15, 2018

Egg turning behavior is an important determinant of egg hatchability, but it remains relatively understudied. Here, we examined egg turning rates and egg temperatures in Forster’s terns (Sterna forsteri). We used artificial eggs containing a data logger with a 3-D accelerometer, a magnetometer, and a temperature thermistor to monitor parental incubation behavior of 131 tern nests. Overall, adults turned their eggs an average (±SD) of 3.8 ± 0.8 turns h-1, which is nearly two times higher than that of other seabirds. Egg turning rates increased with nest initiation date. We also examined egg turning rates and egg temperatures in relation to egg mercury contamination. Mercury contamination has been shown to be associated with reduced egg hatchability, and we hypothesized that mercury may decrease egg hatchability via altered egg turning behavior by parents. Despite the high variability in egg turning rates among individuals, the rate of egg turning was not related to mercury concentrations in sibling eggs. These findings highlight the need for further study concerning the potential determinants of egg turning behavior.

Citation Information

Publication Year 2018
Title Egg turning behavior and incubation temperature in Forster’s terns in relation to mercury contamination
DOI 10.1371/journal.pone.0191390
Authors Gregory T. Taylor, Joshua T. Ackerman, Scott A. Shaffer
Publication Type Article
Publication Subtype Journal Article
Series Title PLoS ONE
Series Number
Index ID 70195764
Record Source USGS Publications Warehouse
USGS Organization Western Ecological Research Center