A Preliminary Assessment of Hawksbill Turtles In Palm Beach County Waters Larry Wood, Marinelife Center of Juno Beach, Florida
Project objectives Characterize Palm Beach County’s hawksbill population structure Investigate the relationships between individuals of this population and other populations Test the feasibility of photo-identification Investigate the role of hawksbills in the reef community Establish the importance of Palm Beach County reefs as developmental habitat for this Critically Endangered species
Area of Focus
Larry’s ledge 47 yellowtail shark canyon, 44 43 28 02 31 a.k.a. n.w. double 16 12 27 33 45 07 30 ledges mid-reef nun’s ledge 42 26 0405 11 10 Jolly Jeff’s
governor’s walk 23 25 32 21 37 01 north double ledges 38 29 17 13 22 36 19 24 03 15 08 41 39 6-7 windows, turtle mound Ron’s “south rock breakers” teardrop
Size class of captures (n=54) 20 18 16 14 # of captures 12 10 8 6 4 2 0 0-10 11-20 21-30 31-40 41-50 51-60 61-70 71-80 81-90 straight carapace length (cm)
Depth at capture (n=54) 25 20 # captures 15 10 5 0 0-5 6-10 11-15 16-20 21-25 depth (m)
Photographic Identification
Epibiont patterning
Cranial scute pigmentation
Results so far… 54 turtles captured in 51 days diving 24 confirmed re-sightings representing 13 turtles Longest records: 220, 250, 680* days All seen in close proximity to capture site Efficacy of hand-capture proven 21% have Milliporina (Hydrozoa) colonies on carapace
The next year… Tissue samples to be analyzed for stock assessment Blood collection for gender determination Begin to characterize reef habitats with digital videography Expand study area
Many Thanks! Dr. Anne Meylan, Amy Fifer, Chris Johnson, Dave Cowan, Mike O’Neil, all dive assistants
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