title: The reproductive hormone cycle of adult female American alligators from a barrier island population.
abstract: Comparatively, little data are available detailing the geographic variation that exists in the reproductive endocrinology of adult alligators, especially those living in barrier islands. The Merritt Island National Wildlife Refuge (MI) is a unique barrier island environment and home to the Kennedy Space Center (FL, USA). Seasonal patterns of sex steroids were assessed in adult female American alligators from MI monthly from 2008 to 2009, with additional samples collected at more random intervals in 2006, 2007, and 2010. Plasma 17β-estradiol and vitellogenin concentrations peaked in April, coincident with courtship and mating, and showed patterns similar to those observed in adult female alligators in other regions. Plasma concentrations of progesterone, however, showed patterns distinctly different than those reported for alligator populations in other regions and remained relatively constant throughout the year. Plasma DHEA peaked in July around the time of oviposition, decreased in August, and then remained constant for the remaining months, except for a moderate increase in October. Circulating concentrations of DHEA have not been previously assessed in a female crocodilian, and plasma concentrations coincident with reproductive activity suggest a reproductive and/or behavioral role. Interestingly, plasma testosterone concentrations peaked in May of 2008, as has been shown in female alligator populations in other regions, but showed no peak in 2009, demonstrating dramatic variability from year to year. Surveys showed 2009 to be particularly depauperate of alligator nests in MI, and it is possible that testosterone could serve as a strong indicator of breeding success.
authors.affiliation: Department of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USADepartment of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA heather.hamlin@maine.edu.
authors.forename: Heather J
authors.initials: HJ
authors.lastname: Hamlin
authors.affiliation: Department of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Russell H
authors.initials: RH
authors.lastname: Lowers
authors.affiliation: Department of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USADepartment of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Satomi
authors.initials: S
authors.lastname: Kohno
authors.affiliation: Department of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Naoko
authors.initials: N
authors.lastname: Mitsui-Watanabe
authors.affiliation: Department of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USADepartment of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Haruna
authors.initials: H
authors.lastname: Amano
authors.affiliation: Department of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Hara
authors.affiliation: Department of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Ohta
authors.affiliation: Department of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USADepartment of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Miyagawa
authors.affiliation: Department of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USADepartment of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Taisen
authors.initials: T
authors.lastname: Iguchi
authors.affiliation: Department of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USADepartment of BiologyUniversity of Florida, Gainesville, Florida, USASchool of Marine SciencesUniversity of Maine, 5751 Murray Hall, Orono, Maine 04469, USAInnovative Health ApplicationsKennedy Space Center, Merritt Island, Florida, USAInstitute of Environmental EcologyEnvironmental Risk Research Center, IDEA Consultants, Inc., Yaizu, Shizuoka, JapanFaculty of Fisheries SciencesHokkaido University, Hokkaido, JapanSchool of Marine ScienceKitasato University, Kanagawa, JapanDepartment of Veterinary MedicineFaculty of Agriculture, Tottori University, Tottori, JapanDepartment of Basic BiologyFaculty of Life Science, The Graduate School for Advanced Studies (SOKENDAI), Okazaki, Aichi, JapanOkazaki Institute for Integrative BioscienceNational Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi, JapanHollings Marine LaboratoryDepartment of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Louis J
authors.initials: LJ
authors.lastname: Guillette
mesh_terms: D000489:Alligators and Crocodiles / Q000097:blood*; D000818:Animals; D003380:Courtship; D003687:Dehydroepiandrosterone / Q000097:blood; D004958:Estradiol / Q000097:blood; D005260:Female; D005431:Florida; D006728:Hormones / Q000097:blood*; D010058:Oviposition; D010507:Periodicity; D011374:Progesterone / Q000097:blood; D012098:Reproduction; D012621:Seasons; D012726:Sexual Behavior, Animal; D013739:Testosterone / Q000097:blood; D013997:Time Factors; D014819:Vitellogenins / Q000097:blood
chemical_list: D006728:Hormones; D014819:Vitellogenins; D013739:Testosterone; D003687:Dehydroepiandrosterone; D011374:Progesterone; D004958:Estradiol