Seagrass,Seagrass,Seagrass,Seagrass,algal blooms &algal blooms &
th IRLth IRLthe IRLthe IRL
C JacobyC Jacoby
Is the IRL important?Is the IRL important?•• Comprises 3 Comprises 3 waterbodieswaterbodies
St t h 156 ilSt t h 156 ilNew Smyrna Beach
•• Stretches 156 milesStretches 156 miles•• Spans 5 countiesSpans 5 counties
Banana RiverBanana River
Mosquito LagoonMosquito Lagoon
•• National Estuary ProgramNational Estuary Program•• Generates $3.7BGenerates $3.7B
Banana RiverBanana River
Indian RiverIndian River
–– $1.3B recreation$1.3B recreation–– $0.9B real estate values$0.9B real estate values
Indian RiverIndian River
•• Supports 15,000 jobsSupports 15,000 jobs•• Supports > 4 000 speciesSupports > 4 000 species West Palm BeachSupports > 4,000 speciesSupports > 4,000 species
Is seagrass important?Is seagrass important?
•• Ecological rolesEcological rolesgg–– habitat (> 80% of valued fish use)habitat (> 80% of valued fish use)–– food (e.g., manatees)food (e.g., manatees)( g )( g )–– improves water qualityimproves water quality
oo absorb nutrientsabsorb nutrientsoo reduce sediment reduce sediment resuspensionresuspension
Is seagrass important?Is seagrass important?•• Management roleManagement role
l i i d d t t i t l dl i i d d t t i t l d–– lagoon impaired due to nutrient loadslagoon impaired due to nutrient loads–– TMDL & BMAP establishedTMDL & BMAP established
l t i tl t i t l tl t–– lower nutrients lower nutrients clearer waterclearer water–– clearer water clearer water greater light penetrationgreater light penetration
d & i t t li htd & i t t li ht–– seagrass needs & integrates lightseagrass needs & integrates light–– deep edge of meadow = metric of successdeep edge of meadow = metric of success
What does the TMDL mean?What does the TMDL mean?
N th IRLNorthern IRL
Banana Ri er Lagoon
WaterbodyReductionTN TP
River LagoonN-IRL 22% 44%BRL 40% 62%
Central IRL
C-IRL 51% 47%
Central IRL
What does impairment mean What does impairment mean to seagrass?to seagrass?
Seagrass assessment1986 – 1989
How has seagrass been How has seagrass been doing?doing?
2.5
acre
s)
Melbourne
(hec
tare
= 2
rass
cov
er
Vero Beach
Sea
gr
How has seagrass been doing?How has seagrass been doing?
2 500
3,000Port St. John
1,000
1,500
2,000
2,500
Port St. John
2.5
acre
s)
0
500
Eau Gallie (hec
tare
=
600
800
1,000
1,200Eau Gallie
rass
cov
er
0
200
400
600
Sea
g
What led to improvement?What led to improvement?
2.5
acre
s)(h
ecta
res
= ra
ss c
over
(S
eagr
Drought &Vero WWTP discharge
‘04 hurricanessurge & flushing
Mini-drought
Drought &IRFWCD di h
TS Fayflushing
surge & flushing IRFWCD discharge
What led to improvement?What led to improvement?
60
70
Vero Beach – S. Central IRL
~62”30‐yr mean* = 56.6” Inter-decadal
drop of ~12” in moving average ch
es)
20
30
40
50
60~50”
m g gannual rainfall
~20% reduction in watershed e
rain
fall
(in
0
10
20 watershed nutrient loadings
Aver
age
What changed?What changed?
2010 2011 2012
Two phytoplankton (microalgal) blooms
Dec 24Oct 3
2010
Apr 1 July 3
2011
Sep14 Oct 23 Dec 8 Mar 18
2012
Superbloom in the north –record magnitude & duration
2° bloom in CIRL –long duration
What happened to seagrass?What happened to seagrass?
5
88
9
5
88
9
5
88
92009 to 2011 to2010 to-100 -100 200 0-100 200200 00
Percentage gain (green), loss (red) & sustained loss (black)
9
11
13
14
17
19
9
11
13
14
17
19
9
11
13
14
17
19
2009 to2010
2011 to2012
2010 to2011
89
21
22
23
25
28
89
21
22
23
25
28
89
21
22
23
25
28
30
32
34
74
37
39
30
32
34
74
37
39
30
32
34
74
37
39
41
43
45
47
49
51
41
43
45
47
49
51
41
43
45
47
49
51
75
55
75
55
75
55
What happened to seagrass?What happened to seagrass?
•• SeagrassesSeagrasses shadedshadedSeagrassesSeagrasses shadedshaded•• SeagrassesSeagrasses lostlost
lagoonlagoon wide ~ 32 000 acreswide ~ 32 000 acres–– lagoonlagoon--wide ~ 32,000 acreswide ~ 32,000 acres–– BRL ~ 21,000 acresBRL ~ 21,000 acres
NIRL ~ 5 000 acresNIRL ~ 5 000 acres–– NIRL ~ 5,000 acresNIRL ~ 5,000 acres–– CIRL ~ 6,000 acresCIRL ~ 6,000 acres
Why did this happen?Why did this happen?Eutrophication
progressionschemescheme
IncreasedIncreasednutrient deliverynutrient delivery
Enhanced growthEnhanced growthEnhanced growthEnhanced growthphytoplankton &phytoplankton &
macroalgaemacroalgae
Increased shading &Increased shading &benthic respirationbenthic respiration
Seagrass lossSeagrass lossSeagrass lossSeagrass lossAdapted from C.M. Duarte (1995)
Why did this happen?Why did this happen?Following C-1 Canalconstruction
Historical watersheds(Pre-1920s)
B f 572 000
Melbourne‐TillmanWater Control District
Before 572,000 acresAfter 1.4 million acresMore than double!
St. Johns River Basin
Indian River Lagoon Basin
Why did this happen?Why did this happen?1920s 1940s 1970s 1990s
DevelopmentDevelopmentAgricultureNaturalWaterOther
Why did this happen?Why did this happen?600000
Total zooplankton
400000
500000
95%
CL
300000
bers
m-3
±
200000
Mea
n nu
mb
0
100000M
2004 2005 2006 2007 2009 2010 2011
Why did Why did thsths happen?happen?6
V1 V2 V3 V4 V5 V6
4
5
SE
Chione sp. (venus clam)16.3–27.7 °C32 6 37 2
3
4
num
ber ± 32.6–37.2
1
2
Mea
n
0
1
2008 2009 2010 2011 2012Year
Why did this happen?Why did this happen?
25V1 V2 V3 V4 V5 V6
Anomalocardia a beriana20
SE
Anomalocardia auberiana(pointed venus)
10
15
num
ber ±
S
5
10
Mea
n
02008 2009 2010 2011 20122008 2009 2010 2011 2012
Year
What will happen next?What will happen next?
•• Seagrass recovery?Seagrass recovery?g yg y•• Repeat of bloom conditions?Repeat of bloom conditions?•• Improve understandingImprove understandingImprove understandingImprove understanding
–– IRL 2011 Scientific ConsortiumIRL 2011 Scientific Consortium–– IRL Symposium 2013IRL Symposium 2013IRL Symposium 2013IRL Symposium 2013–– this symposiumthis symposium
•• “Assist” recovery“Assist” recovery•• Assist recoveryAssist recovery•• Prevent occurrencePrevent occurrence