Sea Turtle Assessment Research Projects

The Sea Turtle Assessment program supports NOAA Fisheries Science Center-led projects and works to improve the quality of sea turtle assessments by addressing themes drawn from the 2013 Sea Turtle Assessment Status and Research Needs report, Endangered Species Act recovery plans and 5-year reviews, and the 2004 marine protected species stock assessment implementation plan (SAIP), including data and analysis gaps. Projects have included those that collect data and conduct research and analyses related to stock identification, abundance and distribution, life history and vital rates, and anthropogenic impacts For more information regarding the Sea Turtle Program Contact: Erin McMichael, erin.mcmichael@noaa.gov, NMFS Office of Science and Technology.

Funded Projects:

2024-2026

• Robust design mark-recapture modeling to improve abundance and trend estimates and optimize survey design for turtle populations in the Pacific Islands Region (PIFSC, PIRO)
• Evaluation of a novel leatherback satellite tag anchor to allow deployments in longline fisheries (SEFSC, NEFSC, OPR, PIFSC)
• Integrating new genomic markers and sample collection to improve stock assessments of Atlantic loggerhead, leatherback and green turtles (SWFSC, SEFSC)
• Using skeletochronology and multiple recaptures to validate epigenetic aging (DNA methylation) for multiple sea turtle populations and species (SWFSC, SEFSC, PIFSC)
• Establishing sex-markers to determine hatchling sex ratios for Hawaiian green turtles in light of climate impacts: validation and application of a novel epigenomic technique (PIFSC)
• Comprehensive genomics assessment of Pacific leatherbacks to improve understanding of population structure, connectivity and the precision of stock ID (SWFSC, PIFSC)
• Estimating green turtle abundance at two U.S. foraging sites and establishing best practices for UAS-based marine turtle monitoring (SWFSC, SEFSC)

2022-2023

2020-2021

• Applying new genomics tools to assess leatherback population vital rates; age to maturity and breeding sex ratios (SWFSC)
• Establishing novel methods for determining reproductive status and age-at-maturity in sea  turtles (SWFSC)
• Assessing abundance, distribution, and dive behavior of western Pacific leatherback turtles off the U.S. West Coast in the context of declining nesting trends and ongoing bycatch risk (SWFSC)
• Evaluating use of Near Infrared Spectroscopy (NIRS) for rapid characterization of sea turtle age and sex, with potential for non-invasive sampling (SEFSC)
• Demographic structure and breeding sex ratios of central Pacific hawksbill turtles (SWFSC)
• Tracking reproductively active adult green turtles after the loss of the iconic index nesting beach for the Central North Pacific Distinct Population Segment (PIFSC)
• Updated analysis for management to improve estimation of anthropogenic impact on the NWA loggerhead population (NEFSC)

2018-2019

• Population vital rates of leatherbacks; age to maturity and breeding sex ratios (SWFSC)
• Incorporating climate impacts into marine turtle population assessment models (PIFSC)
• Establishing life history parameters for sea turtles: age, size, growth validation, and age-at-neritic recruitment (SWFSC)
• Leatherback Turtles (Dermochelys coriacea) foraging areas and movement in the Gulf of Mexico (SEFSC)
• Population genetics and demographic assessment of central Pacific hawksbill turtles (SWFSC and PIFSC)

2016-2017

• Comparing Pacific and Atlantic leatherback population vital rates using genetic approaches (SWFSC)
• Improving stock boundary delineation and demographic parameters for green turtles (SWFSC)
• Improving population vital rate data for the Hawaiian green sea turtle (PIFSC)
• Quantifying marine turtle bycatch in small scale coastal fisheries of the Western Pacific (PIFSC)
• Assessing changes in the abundance and foraging habitat of western Pacific leatherback turtles off the U.S. West Coast in the context of a strong El Niño and decadal-scale climate variation (SWFSC)
• Atlantic Kemp’s ridley age, growth dynamics, habitat use, and trophic ecology, with comparison to the Gulf of Mexico (SEFSC and NEFSC)

2015

• Refining methods for characterizing and monitoring sea turtle population sex ratios (SWFSC and SEFSC)
• Fine scale genetic population assessment of leatherback turtles (SWFSC)
• Occurrence and distribution of loggerhead turtles off of southern California, USA (SWFSC)
• Space use, movement, and distribution of leatherback turtles (Dermochelys coriacea) in the Gulf of Mexico II (SEFSC)
• Projecting the effects of climate change on leatherback turtle habitat within the U.S. Northeast Shelf (NEFSC)
• Using satellite telemetry data to estimate loggerhead availability to aerial observers in the poorly-understood northern Northwest Atlantic Ocean (NEFSC)

2014

• Stock structure, connectivity and breeding sex ratios of Pacific hawksbills (SWFSC)
• Establishing sex ratios of sea turtle foraging populations: validation of a novel testosterone hormone assay technology and sex assessment for five species (SWFSC)
• Establishing demographic parameters for loggerhead turtles in the northeastern Pacific Ocean: growth rates, age determination, annual habitat use, and population connectivity (SWFSC)
• Synthesis and analysis of environmental data to inform the interpretation of in-water and survey data and to improve assessment quality (NEFSC)
• Characterization of loggerhead sea turtle abundance and habitat use at a seasonal 'hot spot' using mark-recapture, autonomous underwater vehicle (AUV) surveys and telemetry (SEFSC)
• Space use, movement, and distribution of leatherback turtles (Dermochelys coriacea) in the Gulf of Mexico (SEFSC)
• Nearshore habitat usage of juvenile Kemp’s ridleys in the Northern Gulf Of Mexico (SEFSC)

2013

• Establishing demographic parameters of green turtles along the U.S. West Coast: survival rates, abundance, sex ratios, age validation, age at neritic recruitment, and population connectivity (SWFSC)
• Tracking the sea turtle "lost years": early dispersal,  survival, foraging ecology and habitat use of oceanic stage sea turtles in the Gulf of Mexico (SEFSC)
• Stock structure, connectivity and breeding sex ratios of eastern Pacific hawksbills (SWFSC)
• Tracking juvenile leatherbacks in the central Pacific Ocean (PIFSC)
• Assessing abundance and foraging habitat affinities of western Pacific leatherback turtles in coastal waters of California, USA (SWFSC)
• Improving capacity of stock assessment for sea turtles: using ocean circulation modeling to inform genetic mixed stock analysis (SWFSC and PIFSC)

2012

• Second meeting of the Pacific Leatherback Assessment Working Group (PIFSC and SWFSC)
• Applying new genetic approaches to improve quality of population assessment of green and loggerhead turtles (SWFSC)
• Annual survival of Peninsular Florida nesting loggerhead turtles (SEFSC)
• Application of new genetic approaches to obtain population vital rate parameters in leatherbacks (SWFSC)
• Northwest Atlantic loggerhead nesting variability and trends: a mechanistic modeling approach to understand the synergistic effects of climate and fisheries (NEFSC)

2011

• 2011 aerial survey of distribution and abundance of western Pacific leatherback turtles (Dermochelys coriacea) in coastal waters of Oregon and Washington (SWFSC)
• Applying new genetic approaches to improve quality of population assessment of leatherback turtles (SWFSC)
• Establishing life history parameters for marine turtles: sex ratios, age validation, and age at neritic recruitment (SWFSC)
• Assessment of age and size at maturation and adult stage duration for loggerhead sea turtles in the western North Atlantic (SEFSC)
• Neonate loggerhead dispersal, behavior, and survivorship in the Western North Atlantic (SEFSC)

2010

• Aerial survey of distribution and abundance of western Pacific leatherback turtles (Dermochelys coriacea) in coastal waters of Oregon and Washington (SWFSC)
• Elucidating stock boundaries and Distinct Population Segment structure for green turtles (SWFSC)
• Stable isotope analysis of marine turtle tissues and further development of 'isotopic map' for the Pacific Ocean (SWFSC)
• Pelagic survival of juvenile loggerheads (SEFSC)