Migration Corridors and Threats in the Gulf of Mexico and Florida Straits for Loggerhead Sea Turtles - Along migration corridors, animals can face natural and anthropogenic threats that differ from those in breeding and non-breeding residence areas. Satellite telemetry can aid in describing the timing and location of these migrations. We use this tool with switching state-space modeling and line kernel density estimates to identify migration corridors of post-nesting adult female loggerhead sea turtles (Caretta caretta, n = 89 tracks) that nested at five beaches in the Gulf of Mexico. Turtles migrated in both neritic and oceanic areas of the Gulf of Mexico with some exiting the Gulf. High-use migration corridors were found in neritic areas to the west of Florida and also in the Florida Straits. Repeat tracking of post-nesting migrations for eight turtles showed variability in track overlap, ranging from ∼13 to 82% of tracks within 10 km of each other. Migration primarily occurred in July and August. We document the longest known post-nesting migration to-date of a wild adult female loggerhead of >4,300 km, along with an apparent stopover of about 1 month. Migration corridors overlaid on three spatially explicit anthropogenic threats (shipping density, commercial line fishing, and shrimp trawling) showed hotspots in the Florida Straits, off the northwest Florida coast and off the coast of Tampa Bay. Identifying where and at what intensity multiple human activities and natural processes most likely occur is a key goal of Cumulative Effects Assessments. Our results provide the scientific information needed for designing management strategies for this threatened species. Information about this loggerhead migration corridor can also be used to inform adaptive management as threats shift over time.TSA Magazine ArchivesDownload back issues of Turtle Survival, the TSA's annual publication, below. Members receive the full-color magazine each year, as a benefit of their membership in the TSA. To purchase print copies of back issues, visit our STORE!DONATE HERE
ORIGINAL RESEARCH
published: 09 April 2020
doi: 10.3389/fmars.2020.00208
Edited by:
Michael Paul Jensen,
Southwest Fisheries Science Center
(NOAA), United States
Reviewed by:
Mariana M. P. B. Fuentes,
Florida State University, United States
Antonios D. Mazaris,
Aristotle University of Thessaloniki,
Greece
*Correspondence:
Autumn R. Iverson
ariverson@ucdavis.edu
Specialty section:
This article was submitted to
Marine Megafauna,
a section of the journal
Frontiers in Marine Science
Received: 22 November 2019
Accepted: 17 March 2020
Published: 09 April 2020
Citation:
Iverson AR, Benscoter AM,
Fujisaki I, Lamont MM and Hart KM
(2020) Migration Corridors
and Threats in the Gulf of Mexico
and Florida Straits for Loggerhead
Sea Turtles. Front. Mar. Sci. 7:208.
doi: 10.3389/fmars.2020.00208
Migration Corridors and Threats in
the Gulf of Mexico and Florida Straits
for Loggerhead Sea Turtles
Autumn R. Iverson1* , Allison M. Benscoter2, Ikuko Fujisaki3, Margaret M. Lamont4 and
Kristen M. Hart2
1 Cherokee Nation Technologies, Contracted to Wetland and Aquatic Research Center, U.S. Geological Survey, Davie, FL,
United States, 2 Wetland and Aquatic Research Center, U.S. Geological Survey, Davie, FL, United States, 3 Fort Lauderdale
Research and Education Center, University of Florida, Davie, FL, United States, 4 Wetland and Aquatic Research Center, U.S.
Geological Survey, Gainesville, FL, United States
Along migration corridors, animals can face natural and anthropogenic threats that differ
from those in breeding and non-breeding residence areas. Satellite telemetry can aid in
describing the timing and location of these migrations. We use this tool with switching
state-space modeling and line kernel density estimates to identify migration corridors
of post-nesting adult female loggerhead sea turtles (Caretta caretta, n = 89 tracks) that
nested at five beaches in the Gulf of Mexico. Turtles migrated in both neritic and oceanic
areas of the Gulf of Mexico with some exiting the Gulf. High-use migration corridors were
found in neri