News on PIFSC Sea Turtle Research

▶ In April, Shawn Murakawa, a biologist in the Marine Turtle Research Program (MTRP) successfully defended her University of Hawaii Master's thesis in Animal Sciences. Her thesis was entitled "Determination of growth spurts in Hawaiian green sea turtles using skeletochronology and histological analysis of gonads". Shawn conducted her research and graduate course work with support from the NOAA Advanced Studies Program.

▶ T. Todd Jones of the Marine Turtle Assessment Program has been collaborating with MTRP leader George Balazs on a project to measure the drag load imposed by Chelonibia barnacles on Hawaiian green turtles. Using barnacles obtained by MTRP decades ago, along with photo documentation, Jones is developing protocols for measuring the drag in wind-tunnel simulation studies to be conducted at the University of British Columbia in Vancouver, Canada.

▶ PIFSC scientist Denise Parker of the University of Hawaii Joint Institute for Marine and Atmospheric Research is first author of a manuscript entitled "Variability in transmission duration of dual satellite tags on sea turtles tracked in the North Pacific Ocean." In the manuscript, she and colleagues George Balazs and Marc Rice (Hawaii Preparatory Academy) describe a novel approach to estimating the most likely survival status of a sea turtle by measuring variation in transmitter duration between paired, identical satellite tags placed on each of 21 turtles: 16 loggerheads, 2 green turtles, and 3 olive ridleys. Transmitter durations ranged from 0-898 days. In 42% of the turtles studied, transmitters stopped sending signals with no significant difference between the pair of satellite tags in the duration of transmissions. However, in the other 58% of cases, paired transmitters showed significant differences in duration of transmissions, with durations ranging from 5-347 days. Overall, results suggest that early cessation of transmission does not always indicate turtle mortality. After the manuscript clears the Center's internal review and approval process, the authors will submit it to the peer-reviewed journal Pacific Science.