We examined habitat selection by green turtles Chelonia mydas at Dry Tortugas National Park, Florida, USA. We tracked 15 turtles (6 females and 9 males) using platform transmitter terminals (PTTs); 13 of these turtles were equipped with additional acoustic transmitters. Location data by PTTs comprised periods of 40 to 226 d in varying months from 2009 to 2012. Core areas were concentrated in shallow water (mean bathymetry depth of 7.7 m) with a comparably dense coverage of seagrass; however, the utilization distribution overlap index indicated a low degree of habitat sharing. The probability of detecting a turtle on an acoustic receiver was inversely associated with the distance from the receiver to turtle capture sites and was lower in shallower water. The estimated daily detection probability of a single turtle at a given acoustic station throughout the acoustic array was small (<0.1 in any year), and that of multiple turtle detections was even smaller. However, the conditional probability of multiple turtle detections, given at least one turtle detection at a receiver, was much higher despite the small number of tagged turtles in each year (n = 1 to 5). Also, multiple detections of different turtles at a receiver frequently occurred within a few minutes (40%, or 164 of 415, occurred within 1 min). Our numerical estimates of core area overlap, co-occupancy probabilities, and habitat characterization for green turtles could be used to guide conservation of the area to sustain the population of this species.
Citation Information
Publication Year | 2016 |
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Title | Habitat selection by green turtles in a spatially heterogeneous benthic landscape in Dry Tortugas National Park, Florida |
DOI | 10.3354/ab00647 |
Authors | Ikuko Fujisaki, Kristen M. Hart, Autumn R. Sartain-Iverson |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Aquatic Biology |
Index ID | 70169971 |
Record Source | USGS Publications Warehouse |
USGS Organization | Wetland and Aquatic Research Center |