Florida Bay Update: The return of seagrass dieoff

Penny Hall Jim Fourqurean

Butler et al 1995 MEPS

Peterson et al 2006 MEPS

Fourqurean and Robblee 1999 Estuaries Fourqurean et al 1993 Estuaries==ne Coastal and Shelf Sci

Borum et al. (2005) Journal of Ecology

“Die-off” only refers to turtle grass; Shoal grass and manatee grass have survived Confirmed die-off area (in red) indicates where dead turtle grass has been observed; Red ≠ 100% dead, the area includes live turtle grass patches of varying size Impacted = mixed healthy and dead

Rankin Lake

Thalassia

Halodule

Syringodium

199519

9619

9719

9819

9920

0020

0120

0220

0320

0420

0520

0620

0720

0820

0920

1020

1120

1220

1320

14

2015

S20

15 F

0

1

2

3

4

5

199519

9619

9719

9819

9920

0020

0120

0220

0320

0420

0520

0620

0720

0820

0920

1020

1120

1220

1320

14

2015

S20

15 F

0

1

2

3

4

5

199519

9619

9719

9819

9920

0020

0120

0220

0320

0420

0520

0620

0720

0820

0920

1020

1120

1220

1320

14

2015

S20

15 F

0

1

2

3

4

5

Johnson Key Basin

199519

9619

9719

9819

9920

0020

0120

0220

0320

0420

0520

0620

0720

0820

0920

1020

1120

1220

1320

14

2015

S20

15 F

0

1

2

3

4

5Thalassia

Halodule

Syringodium 19

9519

9619

9719

9819

9920

0020

0120

0220

0320

0420

0520

0620

0720

0820

0920

1020

1120

1220

1320

14

2015

S20

15 F

0

1

2

3

4

5

199519

9619

9719

9819

9920

0020

0120

0220

0320

0420

0520

0620

0720

0820

0920

1020

1120

1220

1320

14

2015

S20

15 F

0

1

2

3

4

5

Total Seagrass September vs. May 2015

+3<Mean BB≤+4 +4<Mean BB≤+5

-1<Mean BB≤1 +1<Mean BB≤+2 +2<Mean BB≤+3

-1>Mean BB≤-2 -2>Mean BB≤-3 -3>Mean BB≤-4 -4>Mean BB≤-5

Total Seagrass May 2015

0=Mean BB 0<Mean BB≤1 1<Mean BB≤2 2<Mean BB≤3

3<Mean BB≤4

4<Mean BB≤5

Total Seagrass September 2015

0=Mean BB 0<Mean BB≤1 1<Mean BB≤2 2<Mean BB≤3

3<Mean BB≤4

4<Mean BB≤5

-15-10

-505

101520

0 3 6 9 12Month

Mon

thly

Wat

er F

lux (c

m)

Nuttle et al. 2000 Water Resources Research 36(7)1805-1822

Rainfall

Evaporation

Runoff R-E

Water balance in Florida Bay is nearly a balance between rainfall and evaporation, so every freshwater source is important in moderating salinity in the central bay