Tagging Project aids in Endangered Sea Turtle Conservation
12 February 2024
From Anna Marie G. Gonzales, Navy Region Hawaii Public Affairs
JOINT BASE PEARL HARBOR-HICKAM, Hawaii - Sea turtles are an important part of the culture and natural resource heritage of Hawaii and are a key part of the marine ecosystem, reminding us that it is our responsibility to protect threatened or endangered species in our ocean.
Recently, researchers from the National Oceanic and Atmospheric Administration’s (NOAA) Fisheries, also known as the National Marine Fisheries Service and the Pacific Islands Fisheries Science Center (PIFSC) attached satellite transmitters to the shells of green (honu) and hawksbill (honu’ea) sea turtles in Pearl Harbor to begin collecting data about their daily behaviors and movements to understand and reverse declining population trends.
The telemetry tagging effort is part of a 10-year Interagency Agreement (IAA) between Naval Facilities Engineering Systems Command (NAVFAC) Hawaii and the NMFS PIFSC. The joint program is being funded by the Navy and is the first ever turtle tagging study to document the movements and ranges of endangered sea turtles in Pearl Harbor.
“We are excited about this project because we’ve had conversations with our Navy partners since at least 2020 about the need for data on sea turtles in Pearl Harbor,” said Summer Martin, NOAA research biologist supervisor. “We all worked together to make this project happen, and it’s one that aligns well with our mission to produce high quality scientific data to understand and recover sea turtle populations.”
“Our mission is to support the recovery of threatened and endangered sea turtle populations which include conducting surveys and tagging to understand how many turtles there are, where they are, how they use and move between different areas such as those used for feeding and breeding, which are typically in separate locations,” added Martin.
The IAA provides an opportunity to streamline and expedite agreements through the coordination of resources and elimination of unnecessary duplication, without entering into a memorandum of agreement or memorandum of understanding.
“Having an interagency agreement with the science center also allows us to look into other projects that we can partner on together so it opens a wide door for us to collaborate,” said Nicole Olmsted, natural resources specialist for NAVFAC Hawaii.”
The NOAA team began the project in January conducting small boat surveys and turtle capture operations every week and shared the process of the project.
“Two freedivers conducted snorkel surveys to observe turtles and were strategic about their captures,” said Martin. “Once they get a turtle, they bring it safely to the surface and work together with the team to transfer the turtle to the boat where they typically capture several turtles in one spot and then bring them back to the dock for processing.”
Before the processing began, the team ensured the turtles were calmed by putting a towel over their eyes and letting them settle into a comfortable position.
“The processing includes all the biological measurements, ID tags, photos, and tissue samples for molecular studies and then the satellite tag is attached using epoxy and a thin strip of fiberglass which is a painless process for the turtle,” said Martin. “The tags are painted with antifouling paint and then the turtles are released back into the water where they were captured.”
Telemetry tagging is a device that uses sensors on aquatic animals, like sea turtles, to record data about the animals and the ocean which helps researchers discover where the animals go and the environment they are in.
“Our goal is to place satellite tags on 20 turtles this year, and so far the team has deployed 13 satellite tags on green sea turtles over the course of four field days,” said Martin. “Telemetry tagging has been around for a few decades and technology has gotten better, especially with Fastloc GPS capability which is accurate to about 20 meters (65 ft.). Packets of data are transmitted to satellites and available for us to download and analyze.”
Over time the collected data will help scientists produce a better understanding of their habitat, growth rates, migration maps and more.
“While you can also find other types of turtles in Hawaii, this project focuses on green and hawksbill turtles because we know they exist in Pearl Harbor and we want to understand how they are using this local habitat,” said Martin.
Green Sea Turtles also known as chelonia mydas grow to about 3-4 ft. long, weighing 250-400 lbs. and living for 70+ years; while Hawksbill turtles, also known as eretmochelys imbricata grow to about 2-3.5 ft. long, weighing 100-150 lbs. with a lifespan of 50+ years.
In addition to the tagging, white alpha-numeric numbers are etched onto the turtles shells where people who find these turtles can help report their location.
“The shell etching numbers start with “P” for Pearl Harbor and are going in sequence for captures that are part of this project. Anyone in the area that sees one of these turtles can report it online through our Honu Count Program,” added Martin.
“Entanglement is a huge hazard so one way to protect turtles is to remove trash from the ocean including fishing gear and nets,” said Olmsted. “Maintain a safe distance from them and do not attempt to touch them. It’s also important to follow speed limits during boating to avoid strikes.”
Helpful tips to protect aquatic animals:
1. Space - Give turtles space in and out of the water 10 feet is a respectful viewing distance.
2. Nesting - Report any suspected nesting activity or hatchlings because we don’t always know where they are. Nesting season is during the summer months.
3. Numbered Turtles - Report any sightings of numbered turtles to Honu Count (find the Honu Count Sighting Survey on www.fisheries.noaa.gov) It’s a great way to contribute to research and monitoring.
4. Stranded Turtles - Report any sick, injured, or dead turtles to the statewide NOAA hotline (888) 256-9840.