Immature Sea Turtles in Gullivan Bay, Ten Thousand Islands, Southwest Florida

An in-water survey for immature endangered and threatened sea turtles in the coastal waters of southwest Florida during 1997-2003 yielded 191 Kemp\u27s ridley (Lepidochelys kempi), 15 loggerhead (Caretta caretta), 13 green (Chelonia mydas), and one hybrid hawksbill (Eretmochelys imbricata)-loggerhead turtle. Mean carapace lengths were 40.3 cm minimum straightline carapace length (MSCL) for Kemp\u27s ridley, 65.5 cm MSCL for loggerhead, and 51.6 cm MSCL for green turtles. Fibropapilloma tumors were found on seven of the green turtles and one loggerhead turtle. The mean growth rate of recaptured Kemp\u27s ridleys was 6.3 cm/yr. The nearshore waters of Gullivan Bay in the Ten Thousand Islands are an important developmental habitat for the highly endangered Kemp\u27s ridley turtle, and to a lesser degree, immature loggerhead and green turtles

Seasonal Migration of Immature Kemp\u27s Ridley Turtles (Lepidochelys kempii Garman) Along the West Coast of Florida

Six immature Kemp\u27s ridley turtles (Lepidochelys hempii) were monitored via satellite telemetry to investigate their winter migration on the west coast of Florida. All turtles departed from Cedar Keys in late Nov., migrated southward in Dec., and overwintered in offshore waters from Anclote Keys to Captiva Island during Jan., 120 km and 296 km from Cedar Keys, respectively. Turtles migrated northward in Feb. and began returning to Cedar Keys in March. Five of the turtles occupied relatively small (3.8-48.0 km2) postmigration foraging ranges through Aug. The sixth turtle returned to Waccasassa Bay, east of Cedar Keys, but locational data were insufficient for postmigration analysis. Mean sea surface temperature (SST) used by turtles in Nov. decreased from 23.6 ± 1.9 C during the first 2 weeks to 17.1 ± 1.5 C during the latter 2 weeks, and corresponded to their departure from Cedar Keys. Mean SST used by turtles in Jan. increased from 14.0 ± 1.6 C during the first 2 weeks to 16.6 ± 1.4 C during the latter 2 weeks, and corresponded to the onset of their northward migration. Turtles traveled up to 13-56 km offshore to maximum depths of 15-31 m. Higher proportions of satellite location classes requiring four or more uplinks were obtained during winter months suggesting that turtles spent more time at the surface during their migrations. Further studies are needed to determine possible size-specific differences in depth use and migration patterns, to identify benthic habitats used by Kemp\u27s ridleys during winter migrations, and to determine what anthropogenic impacts occur within their migratory routes along the Florida coast

A Molecular Assessment of Speciation and Evolutionary History of the Globally Distributed Spotted Eagle Ray (Aetobatus narinari)

The spotted eagle ray (Aetobatus narinari), a species of conservation concern (Near Threatened IUCN category) is commonly associated with coral reef ecosystems worldwide where it is likely to play an important predatory role. Currently described as a single, circumglobally distributed species, geographic differences in parasite diversity have led to suggestions that A. narinari may constitute a species complex. There has been no systematic evidence to support this suggestion, however. If multiple species of spotted eagle ray exist, each will likely posses decreased geographic ranges and population sizes, altering the impacts of threats and requiring separate assessments of conservation needs. We assessed the validity of A. narinari as a single cosmopolitan species using 1570bp of sequence data from two mitochondrial genes (cytochrome b and COI) and the nuclear ribosomal ITS2 locus. Individuals from four major geographic regions were examined: western north Atlantic, and western, central, and eastern Pacific. Phylogenies for each locus concordantly described three distinct lineages (western north Atlantic, western/central Pacific, and eastern Pacific) with no genetic exchange among regions. Genetic distances among the most divergent lineages were comparable to taxonomically uncontroversial batoid and teleost congener pairs. Using combined genealogical concordance and genetic distance results, we recommend 1) that the western/central Pacific lineage be recognized as a distinct species from the western north Atlantic and eastern Pacific lineages, and 2) the western north Atlantic and eastern Pacific lineages, separated by the Isthmus of Panama, be given subspecies status. Dramatically higher nucleotide diversity and sequence divergence coupled with a basal position in multiple phylogenetic analyses support an Indo-West Pacific origin for the A. narinari species complex, with subsequent migration into the Atlantic. Evolutionary relationships among lineages suggest a westerly migration around the southern tip of Africa, with intensification of the Benguela coldwater upwelling system a possible vicariant mechanism underlying speciation

Origin of immature loggerhead sea turtles (Caretta caretta) at Hutchinson Island, Florida: evidence from mtDNA markers

Loggerhead sea turtles (Caretta caretta) are migratory, long-lived, and slow maturing. They are difficult to study because they are seen rarely and their habitats range over vast stretches of the ocean. Movements of immature turtles between pelagic and coastal developmental habitats are particularly difficult to investigate because of inadequate tagging technologies and the difficulty in capturing significant numbers of turtles at sea. However, genetic markers found in mitochondrial DNA (mtDNA) provide a basis for predicting the origin of juvenile turtles in developmental habitats. Mixed stock analysis was used to determine which nesting populations were contributing individuals to a foraging aggregation of immature loggerhead turtles (mean 63.3 cm straight carapace length [SCL]) captured in coastal waters off Hutchinson Island, Florida. The results indicated that at least three different western Atlantic loggerhead sea turtle subpopulations contribute to this group: south Florida (69%), Mexico (20%), and northeast Florida-North Carolina (10%). The conservation and management of these immature sea turtles is complicated by their multinational genetic demographics

Immature Sea Turtles in Gullivan Bay, Ten Thousand Islands, Southwest Florida

An in-water survey for immature endangered and threatened sea turtles in the coastal waters of southwest Florida during 1997-2003 yielded 191 Kemp\u27s ridley (Lepidochelys kempi), 15 loggerhead (Caretta caretta), 13 green (Chelonia mydas), and one hybrid hawksbill (Eretmochelys imbricata)-loggerhead turtle. Mean carapace lengths were 40.3 cm minimum straightline carapace length (MSCL) for Kemp\u27s ridley, 65.5 cm MSCL for loggerhead, and 51.6 cm MSCL for green turtles. Fibropapilloma tumors were found on seven of the green turtles and one loggerhead turtle. The mean growth rate of recaptured Kemp\u27s ridleys was 6.3 cm/yr. The nearshore waters of Gullivan Bay in the Ten Thousand Islands are an important developmental habitat for the highly endangered Kemp\u27s ridley turtle, and to a lesser degree, immature loggerhead and green turtles

Species Delineation and Evolutionary History of the Globally Distributed Spotted Eagle Ray (Aetobatus narinari)

The spotted eagle ray (Aetobatus narinari), a large coral reef–associated batoid of conservation concern, is currently described as a single, circumglobally distributed species. However, geographic differences in its morphology and parasite diversity have raised unconfirmed suspicions that A. narinari may constitute a species complex. We used 1570 bp of mitochondrial and nuclear sequence data (cytochrome b, cytochrome coxidase subunit I, and internal transcribed spacer 2) to assess the validity of A. narinari as a single cosmopolitan species and infer its evolutionary history. Specimens from 4 major geographic regions were examined: the Central Atlantic, Eastern Pacific, Western Pacific, and Central Pacific. Phylogenies described 3 distinct, reciprocally monophyletic lineages with no genetic exchange among regions. Based on combined genealogical concordance and genetic distance criteria, we recommend that the Western/Central Pacific lineage be recognized as a distinct species from lineages in the Central Atlantic and Eastern Pacific. The latter 2 lineages, separated by the Isthmus of Panama, are proposed as subspecies. A basal position in phylogenetic analyses and statistical parsimony results support an Indo-West Pacific origin for the A. narinari species complex, with subsequent westerly dispersal around the southern tip of Africa into the Atlantic and then into the Eastern Pacific

Ecology of east Florida sea turtles : proceedings of the Cape Canaveral, Florida Sea Turtle Workshop, Miami, Florida, February 26-27, 1985 /

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