Lightning Talk

1. Measuring changes to sea
turtle nesting beaches and
their effects on nesting
success using LiDAR data
Kristina Yamamoto, PhD
http://surfspots-gps.com

2. Current Knowledge/Limitations
• Green turtles – like vegetation
• Leatherbacks and loggerheads – do not like
vegetation
• Multiple beaches – rarity
• Beach as a whole – rarity
• Morphological features – rare
• Studies over time - rare

3. LiDAR Background
pitch
roll
z
y
x
yaw
z
y
x
• Laser signals sent
as pulses from
typically in the
ultraviolet (UV),
visible, and near
infrared (NIR)

4. LiDAR Cloud
http://www.pobonline.com/POB/Home/Images/pob1009_woolpert03_LiDAR_Point.jpg

5. Study Species: Loggerhead
• Caretta caretta
• Big head
http://www.supergreenme.com/data/images/27/500x333_Loggerhead_Sea_Turtle-Georgia-Aquarium.jpg /

6. Study Species: Green
• Chelonia mydas
• Soup turtle
http://greatescapetravel.com/

7. Study Species: Leatherback
• Dermochelys
coriacea
• Half the size of a
VW beetle
http://fwie.fw.vt.edu/VHS/reptiles/turtles/leatherback-sea-turtle/leatherback-seaturtle2.jpg/

8. Study Area
One of the largest loggerhead rookeries in the world, one of the largest
green turtle nesting areas in the Atlantic ,and the only continuously used
nesting area in the continental United States for leatherbacks

9. Study Data
Name
Dates
LiDAR topo: Airborne Topographic Mapper
(ATM) II
1999
LIDAR topo/bathy: Joint Airborne LiDAR
Bathymetry Technical Center of Expertise
(JALBTX) using the Compact Hydrographic
Airborne Rapid Total Survey (CHARTS)
system
2004, 2006
Florida Fish and Wildlife Conservation
Commission nesting data
1999-2008

10. Current Knowledge/Limitations
• Green turtles – like vegetation
• Leatherbacks and loggerheads – do not like
vegetation
• Multiple beaches – rarity
• Beach as a whole – rarity
• Morphological features – rare
• Studies over time - rare

11. Methods
• 1999, 2004, and 2006 LiDAR data compared
• How do sea turtle nesting beaches change
over time?
• How does this affect sea turtle nesting
success?
1999
2004
2006

12. Methods
Variables to be Compared Between Beaches
Volume
Elevation
Slope
Beach length, width, area
Orientation
Aspect
Surface roughness
Pixel position

13. Change to Beach Variables
• How does the volume of beaches change over
time?
• Is there a geographic or morphologic pattern?
1999
2004
2006

14. Results: Changes to Beach Variables
Beach
Boca Raton Beaches
Deerfield/Hillsboro Beaches
Delray Beach
Ft Lauderdale Beach
Golden Beach
Gulfstream
Gulfstream Park
Hollywood/Hallandale Beach
John U. Lloyd Beach State Park
Kreusler Park
Lake Worth Municipal Beach
Lantana
Macarthur State Park
Ocean Inlet Park
Ocean Reef Park
Pompano/Lauderdale-by-the-Sea
Singer Island
Sloan's Curve
1999
Volume
0.656
0.654
0.607
0.988
0.143
0.101
0.005
0.626
0.268
0.040
0.022
0.009
0.134
0.025
0.001
1.418
0.102
0.040
2004
Volume
0.813
0.660
0.615
1.193
0.170
0.099
0.006
0.743
0.275
0.035
0.022
0.010
0.199
0.035
0.001
1.934
0.108
0.053
2006
Volume
0.881
0.035
0.708
1.006
0.146
0.136
0.006
0.411
0.284
0.025
0.021
0.007
0.265
0.038
0.011
1.916
0.213
0.079
• No geographic pattern or orientation
correlation with beach change in volume

15. 2: Beach Change over Time
Change to Beach Variables
Is the difference in the amount of sand present
in a beach related to change in other beach
characteristics?
1999
2004
2006

16. 2: Beach Change over Time
Results: Changes to Beach Variables
• Weak correlations to change in volume with
change in other variables
Variable
Change in minimum elevation
Change in maximum elevation
Change in maximum slope
Change in average slope
Change in minimum TPI
Change in maximum TPI
Change in standard deviation of TPI
Change in standard deviation of rugosity
R2
Variable coefficient
0.31
-88940.26
0.18
44982.07
0.21
8490.37
0.13
33350.83
0.22
-113775.60
0.20
55026.90
0.15
183321.30
0.16
3058584.90

17. 2: Beach Change over Time
Results: Changes to Beach Variables
• For minimum elevation, 90% of the beaches
decreased their minimum elevation between
1999 and 2004
• 83% gained between 2004 and 2005
• Similar trends seen for standard deviation of
elevation, maximum slope, and minimum and
standard deviation of TPI

18. 2: Beach Change over Time
Change to Beach Variables
How do changes to beach morphology affect
nesting success?
1999
2004
2006

19. 2: Beach Change over Time
Results: Change in nesting success
Caretta caretta
Variable
R2
Change in minimum elevation
Variable coefficient
Change in maximum slope
0.184
0.158
7.435
-0.809
Change in minimum TPI
0.113
8.919
Change in maximum TPI
0.229
6.400
Chelonia mydas
Variable
Change in mean TPI
R2
Variable coefficient
0.210
645.121

20. 2: Beach Change over Time
Conclusion
• Broad generalizations about the effects of
beach volume changes to a beach’s
morphology cannot be made for this study
area – beaches act as individuals
• Nesting success for Chelonia mydas and
Caretta caretta were not wholly affected by
the observed changes to their nesting beaches