Updates on the DLNR Sea Turtle Program

In the CNMI, the green sea turtle is currently listed as Threatened under the Endangered Species Act, while the Hawksbill is listed as Endangered; both are protected federally and locally by law. Because they are protected, the CNMI DLNR receives funds from NOAA’s Pacific Islands Regional Office to study sea turtle nesting and foraging populations.

The sea turtle research and monitoring program started in 2005. Since then our goals have been to collect scientific data to support adaptive resource management, mitigate local threats to sea turtles and their habitat, and to build community support for sea turtle conservation through education and outreach.

The program consists of four components:

-Morning and night nest monitoring, which involves documenting non-nesting emergences and nests on six Saipan beaches, performing nest inventories to determine hatch and emergence success rates, flipper- and satellite-tagging nesting turtles at night, and taking tissue samples for genetic analysis from nesting turtles or dead hatchlings. We also perform rapid assessment nest counts on Tinian and Rota beaches once a year.

-A nearshore (in-water) capture/tagging program at six locations on Saipan, Tinian, and Rota that have been identified as potential critical habitat areas for immature green and hawksbill turtles.

-A stranding and salvage program, which involves recovering injured, sick, or dead sea turtles, performing necropsies (animal autopsies), collecting organ tissue, skin, and bone samples for lab analysis, and carapaces for educational presentations.

-An education and outreach program that involves performing outreach presentations at local schools, education expos, and community events. This includes our stranding response advertising campaign to let the community know that if they see a sick, dead, or injured turtle it is OK to help! They can report it by calling our stranding hotline at 287-8537, which spells CTRTLES.

CNMI sea turtle stats:

-Over 700 immature turtles hand-captured, tagged, and released on Saipan, Tinian, and Rota waters, of which 660 were green turtles and 50 were hawksbill turtles. DNA tissue sample lab results of this study have shown that CNMI immature turtles originate from other Micronesian islands, such as Yap and Marshall Island rookeries.

-The in-water study has also shown that CNMI’s foraging turtle population is made up of 98 percent juveniles (<2.7 feet in shell length) and 2 percent adults. It takes a juvenile green turtle 30 to 35 years before it matures, reproduces, and replaces itself in the gene pool. Their protection at this life stage is critical if the population is to have a chance to recover! -In-water study results have also shown CNMI immature green turtles maintain a diet of 95 percent macroalgae in coral reef habitats. This translates to sea turtles providing an important ecological service in helping prevent algae overgrowth on corals, which in turn ultimately helps to support healthy fish populations! -In a collaborative project with NOAA’s Pacific Islands Fisheries Science Center, 11 sub-adult turtles captured in-water have been fitted with satellite transmitters in order to track their movements and dive behaviors. Out of these, so far a single hawksbill has migrated out of Tinian waters to Guam, the remainder continue to forage on local reefs. -We have also satellite-tagged six adult turtles on our beaches and through this study have determined that Saipan’s nesting turtles are migrating from Okinawa, Japan, the Philippines, and one calls local waters its home. -From these combined satellite telemetry studies, preliminary results show that most CNMI turtles are a shared international resource; crossing political boundaries in up to 2,500-mile migrations from foraging areas to nesting areas. -In a different collaborative project with the National Institute of Standards and Technology, blood and scute scraping samples were taken from 23 Saipan and Tinian turtles for contaminant analysis (to detect the presence and levels of heavy metals and PFC pollutants in their bodies). This study is ongoing and pollutant levels in CNMI sea turtle results are not yet available. -Data results show a nesting population of from one to 15 adult green turtles nest in the CNMI in any one year. Since 2006, a total of 47 green turtles have nested on Saipan monitored beaches. Of these, 36 percent were permanently removed from the nesting population by directed take (illegal hunting). -This past season (2013/2014) staff documented a total of six nesting green turtles on Saipan (of these one was poached and another was nearly poached from Tank Beach) and two on Tinian (Rota numbers were unknown due to beach erosion from Typhoon Halong prior to our annual rapid assessment). A total of 42 nests were laid this season (one of which was poached on Chulu Beach, Tinian) with a lower than average hatch success rate of 69 percent and emergence success rate of 59 percent. -Flipper-tagged adult Saipan turtles have been found to return to nest every three to six years. Each female lays an average of seven nests in a single nesting season. Each nest contains an average of 91 eggs. Average hatch success rate is 80 percent, while average emergence success rate is 71 percent. -Stranding and salvage recoveries have totaled 69 since 2005. Of these, the cause of stranding or death was determined. Summary: boat strike/collisions, 2; marine debris/entanglement, 2; parasites/emaciation, 9; sharks/predators, 1; Unknown, 1; and directed take (illegal hunting), 54. -Since 2009, education outreach efforts have reached over 10,100 students, volunteers, and workshop participants at over 120 events/presentations. It has been a pleasure for our research team to participate in this shared conservation effort in hopes that future CNMI generations may be able to enjoy sea turtles! -If you have information regarding sea turtle poaching activities, call the NOAA Enforcement hotline at 671-472-7200, CNMI DFW Enforcement at 670-989-6095, Crime Stoppers hotline at 323-PARA, or 911. (By TAMMY SUMMERS, NOAA Affiliate)