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Impacts of the Deepwater
Horizon Oil Spill on Red
Snapper (Lutjanus
campechanus) Larvae in the
Northern Gulf of MexicoJeff Fang
Dr. Frank J. Hernandez, Jr.
University of Southern Mississippi
Gulf Coast Research Lab
About Me• Hometown: Seattle, WA
• University of Portland (2015), OR
o B.S. Biology
• Minor: Psychology
Dr. Frank J. Hernandez, Jr.
• Ph.D. in Evolution, Ecology, and
Organismal Biology
• Lower food web dynamics
o Natural and human impacts on aquatic and marine ecosystems
• Southern Arkansas University
Dr. Jesse E. Filbrun
• Fisheries oceanography
• Current Projects
o Natural Resource Damage Assessment
o Marine Debris
o Gulf of Mexico Research Initiative (GoMRI)*
• Year 4
IntroductionDeepwater Horizon
Oil SpillRed Snapper
April 20, 2010 – September
19, 2014(Hoffman et al. 2011)
Spawn from May/June to
September/October(Moran and Morais 1998; Kulaw 2012)
Hatch ~24 – 27 hours after
fertilization(Rabalais et al. 1980)
Macondo Well
100 mi south, 1500 m deep (Atlas et al. 2011)
Larvae occupy shallow waters
15 – 30 m deep(Szedlmayer et al. 2014)
Introduction• Survival affected by mortality events
• Investigate diets (gut content), growth (size at age), and condition (size)
Null Hypothesis• H01: Larval red snapper diets, growth, and
condition will not differ across periods (before, during, and after the oil spill).
Methods: Overview• Fisheries Oceanography of Coastal Alabama (FOCAL)
o Long-term ichthyoplankton and zooplankton survey
o 2004 – 2011
• Sample Sites:
o T20: 20 m deep
o T35: 35 m deep
• 357 Red snapper larvae
Methods: Condition • Imaging
oCamera-mounted dissecting microscope
• 5x magnification
Methods: Condition
8458_Fish_01_L_campechanus
4.89 mm
Methods: Growth • Otolith extraction
• Imaging
• Measuring
o Longest radius
o Daily rings
• Size vs. Age
Results: Condition
Notochord length (mm)
0 2 4 6 8 10 12 14 16
De
pth
at
pe
cto
ral fin
(m
m)
0
1
2
3
4
5
6
Notochord length (mm)
0 2 4 6 8 10 12 14 16
De
pth
at
an
us (
mm
)
0
1
2
3
4
5
Notochord length (mm)
0 2 4 6 8 10 12 14 16
He
ad
le
ngth
(m
m)
0
1
2
3
4
5
6
Notochord length (mm)
0 2 4 6 8 10 12 14 16
He
ad
he
igh
t (m
m)
0
1
2
3
4
5
6
Notochord length (mm)
0 2 4 6 8 10 12 14 16
Eye
dia
me
ter
(mm
)
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
Notochord length (mm)
0 2 4 6 8 10 12 14 16
Lo
we
r ja
w le
ng
th (
mm
)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
DPF = 0.401 NL - 0.119r = 0.94, P < 0.001
DA = 0.318 NL - 0.237r = 0.94, P < 0.001
HL = 0.383 NL - 0.003r = 0.96, P < 0.001
HH = 0.354 NL + 0.010r = 0.95, P < 0.001
ED = 0.113 NL - 0.009r = 0.96, P < 0.001
LJL = 0.201 NL + 0.001r = 0.96, P < 0.001
r P r P
Depth at pectoral fin (DPF) 0.93 < 0.001 -0.18 0.00
Depth at anus (DA) 0.89 < 0.001 -0.15 0.01
Head length (HL) 0.71 < 0.001 0.41 < 0.001
Head height (HH) 0.94 < 0.001 -0.02 0.71
Eye diameter (ED) 0.65 < 0.001 0.00 0.94
Lower jaw angle length (LJL) 0.62 < 0.001 0.20 < 0.001
NMS Axis 1 (R2 = 0.92) NMS Axis 2 (R
2 = 0.05)
Body dimension
Results: Condition
Results: Condition
NMS Axis 1 (R2 = 0.92)
NM
S A
xis
2 (
R2 =
0.0
5)
MayJuneJulyAugustSeptemberOctober
MRPPA = 0.06P < 0.0001
May Jun Jul Aug Sep Oct
NM
S A
xis
1 (
R2 =
0.9
2)
-4
-3
-2
-1
0
1
2
3
4
MRPPA = 0.06P < 0.0001
Shallow Body Deep Body
Sh
allo
w B
od
yD
ee
p B
od
y
Results: Condition
NMS Axis 1 (R2 = 0.92)
NM
S A
xis
2 (
R2 =
0.0
5)
Station T20Station T35
MRPPA = 0.02P < 0.0001
Station T20 Station T35
NM
S A
xis
1 (
R2 =
0.9
2)
-4
-3
-2
-1
0
1
2
3
4
MRPPA = 0.02P < 0.0001
Shallow Body Deep Body
Sh
allo
w B
od
yD
ee
p B
od
y
Conclusion• Morphometrics: Condition
o Fish caught in earlier months were smaller-bodied
than fish in later months
o Fish caught at T20 were smaller-bodied than those at
T35
Conclusion: Future Direction
• Otolith (length at age), gut (diet),
isotope (diet), and dry weight
(weight at length/condition)
analyses still pending
Conclusion• Other studies:
o 2010 and 2011 were the worst recruitment years
since 1994 (SEDAR 2013)
o Red snapper abundance was lower after the spill
(Patterson and Jagoe)
o Preliminary results show a decline in growth rate at
age after 2010 (Herdter and Murawski 2014)
o No decline in juvenile red snapper abundance in 2011
(Szedlmayer et al. 2014)
Reflection
Acknowledgements • NOAA-NGI Diversity Internship Program
o Natalie Ortell & Tina-Miller Way
• Dauphin Island Sea Lab
• University of Southern Mississippi
• Gulf Coast Research Labo Frank Hernandez, Jesse Filbrun, John Ransom, Carla
Culpepper, Liz Hunt, Ann Evans, Cher Griffin, Jana Herrmann, Jessica Carrier, Lanora Vasquez Del Mercado, Lillian Collins, Sarah Muffelman, Sandra Huynh, Charles Hem, Olivia Lestrade, Page Vick
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