Spatial dynamics of Scleractinian coral populations in the Florida Keys.

Dione W. SwansonSteven G. Smith

Jerald S. AultMark ChiapponeSteven L. Miller

Leanne M. Rutten

Habitat use = amount of space utilized by a population of animals or plants over a fixed period of time

Habitat use analysis:

Requires quantification of habitat abundance in the environment (area) coupled with population abundance metrics

Partitions variation in population abundance

Identifies areas where physical and biological factors that affect population dynamic rates may vary

How do coral populations utilizeHow do coral populations utilizehabitat space in the Florida Keyshabitat space in the Florida Keys

coral reef ecosystem?coral reef ecosystem?

Process inferences from empirical data:Process inferences from empirical data:Juvenile abundance Juvenile abundance Adult abundance and size distributionsAdult abundance and size distributionsPrevalence of mortality factorsPrevalence of mortality factorsEstimates of dead surface areaEstimates of dead surface area

BNP

UpperKeys

MiddleKeys

LowerKeysDry Tortugas

TortugasBank DTNP

Miami

Key West

Dry Tortugas

LowerKeys

TortugasBank DTNP

Key WestMiddleKeys

Miami

BNP

UpperKeys

1999-2002

2005-2006

311 Sites

241 Sites

LRSG

PHBLRHB

HRSG

MPR

OPR

Reef Terrace

Low-Relief Hardbottom

Rocky Outcrops

Pinnacles

Low-ReliefSpur & Groove

Medium Profile Reef

High-ReliefSpur & Groove

Patchy Hardbottom in Sand

Reef Terrace PatchReefs

Florida

Dry Tortugas Miami

Benthic surveysAdult colonies (post-recruits)

coral colonies > 4 cm

10 m x 1.0 m belt transects (20 m2 per site)

Juvenile colonies (recruits)coral colonies < 4 cm

Ten (65-cm x 48-cm) quadrats(3.12m2 per site)

Habitat UseHabitat Use• Probability of use (proportion occurrence)

• Per unit amount of use (density)

• Population amount of use (abundance)

Example species: Montastraea cavernosaMontastraea cavernosa

Densit

y (

no

. co

lonie

s/m

2)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Habitat class

PR IRT SFR MFRA MFRB DFR

Pro

port

ion o

ccu

rren

ce

0.0

0.2

0.4

0.6

0.8

1.0

1.2

De

nsit

y (

no.

colo

nie

s/m

2)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Sampling strata

MPROPR

IRT

HRSG (<6m

)

LRHB (<

6m)

LRSG (<

6m)

LRHB (6

-15m

)

LRSG (6

-15m

)

PHB (6-1

5m)

LRSG (>

15-2

1m)

LRSG (>

21-3

3m)

Pro

po

rtio

n o

cc

urr

en

ce

0.0

0.2

0.4

0.6

0.8

1.0

1.2

M. cavernosa: FL Keys

Near shore

Near shore

Off shore

Off shore

patchreef

shallowfore reef

midforereef

deepfore reef

patchreef

shallowfore reef

midforereef

deepfore reef

Pe

r u

nit

am

ou

nt

of

use

Pro

ba

bil

ity o

f u

se

De

nsit

y (

# c

olo

nie

s/m

2)

0.0

0.5

1.0

1.5

2.0

Habitat class

TBANK-hig

h co

mpl

TBANK-low

com

pl

DTNP-hig

h co

mpl

(>15

-33m

)

DTNP-low

com

pl (>

15-3

3m)

DTNP-hig

h co

mpl

(<6-

15m

)

DTNP-low

com

pl (<

6-15

m)

M/L

Key

s-fo

rere

ef (>

15-3

3m)

L Key

s-fo

rere

ef (6

-15m

)

M/L

Key

s-fo

rere

ef (<

6m)

M/L

Key

s-pa

tchr

eef

B/U K

eys-

fore

reef

(>15

-33m

)

U/M K

eys-

fore

reef

(6-1

5m)

B/U K

eys-

fore

reef

(<6m

)

B/U K

eys-

patc

hree

f (<6

m)

BNP-fore

reef

(6-1

5m)

Pro

po

rtio

n o

cc

urr

en

ce

0.0

0.2

0.4

0.6

0.8

1.0

1.2

*

*

**

*

M. cavernosa

15 Habitat classes

Habitat classes %(A)

Adults (>4 cm) %(PA)

Juveniles (<4 cm) %(PJ)

TBANK-high compl 3.36 14.09 4.09

TBANK-low compl 11.89 12.06 21.99*

DTNP-high compl (>15-33m) 1.31 5.58 1.59

DTNP-low compl (>15-33m) 5.54 5.02 8.55

DTNP-high compl (<6-15m) 0.63 0.78* 0.84

DTNP-low compl (<6-15m) 14.73 12.22* 20.43

M/L Keys-forereef (>15-33m) 7.13 12.07* 11.33

L Keys-forereef (6-15m) 5.60 5.54 9.74*

M/L Keys-forereef (<6m) 2.25 0.78 0.55

M/L Keys-patch reef 8.13 18.03 4.33

B/U Keys-forereef (>15-33m) 2.48 2.08 3.19*

U/M Keys-forereef (6-15m) 13.78 4.49 10.16*

B/U Keys-forereef (<6m) 4.91 0.77 0.40

B/U Keys-patch reef 14.08 6.00* 2.03

BNP-fore reef (6-15m) 4.18 0.48 0.77*

Population use:M. cavernosa - adult vs. juvenile

Maximum diameter (cm)

0 10 20 30 40 50 60 70 80 90100

110120

130140

150160

170180

190200

210

Co

lon

y a

bu

nd

an

ce

0.0

5.0e+6

1.0e+7

1.5e+7

2.0e+7

2.5e+7

3.0e+7

3.5e+7

4.0e+7

4.5e+7

M. cavernosa: Population size structure

n = 1608 (1999-2002)n = 2003 (2005-2006)

p < 0.0001

juv > adult (p<0.05)

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0 10 20 30 40 50 60 70 80 90100

110120

130140

150160

170180

190200

2100.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

De

nsit

y (

no

./m

2)

Maximum diameter (cm)

Positive habitat use

T. Bank – high complexity

DTNP – high complexity(>15-33m)

M/L Keys patch reef

(+/neutral)

(+/neutral)

(+/-)

4.04%

1.37%

8.50%

n = 352 (2005-2006)

n = 202 (1999-2002)

n = 212 (1999-2002)

n = 150 (1999-2002)

n = 195 (2005-2006)

n = 702 (2005-2006)

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0 10 20 30 40 50 60 70 80 90100

110120

130140

150160

170180

190200

2100.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

De

nsit

y (

no

./m

2)

Maximum diameter (cm)

Neutral habitat use

DTNP – low complexity(>15-33m)

L Keys forereef (6-15m)

BNP/U Keys forereef (>15-33m)

(neutral/neutral)

1999-2002 (neutral/neutral)

(+/neutral)

5.80%

5.85%

1.46%

n = 66 (1999-2002)

n = 151 (1999-2002)

n = 51 (1999-2002)

n = 25 (2005-2006)

n = 115 (2005-2006)

n = 43 (2005-2006)

2005-2006 (neutral/+)

p = 0.035p = 0.035

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0 10 20 30 40 50 60 70 80 90100

110120

130140

150160

170180

190200

2100.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

De

nsit

y (

no

./m

2)

Maximum diameter (cm)

Negative habitat useNegative habitat use

BNP/U Keys forereef (<6m)

U/M Keys forereef (6-15m)

M/L Keys forereef (<6m)

(-/-)

(-/-)

2.35%

14.41%

5.14%

n = 149 (1999-2002)

n = 130 (1999-2002)

n = 28 (1999-2002)

n = 36 (2005-2006)

n = 72 (2005-2006)

n = 25 (2005-2006)

2005-2006 (-/neutral)1999-2002 (-/-)

Disease Algal overgrowth

Total live tissue SA

(cm2)

Total recent dead SA

(cm2)

Recent dead SA

(cm2) %p

Recent dead SA

(cm2) %p

Domain 2.328E+11 1.236E+09 4.267E+08 0.692 1.038E+08 3.611

TBANKTBANK--high compl high compl 4.071E+10 2.845E+08 2.254E+08 1.996 3.693E+07 3.128

DTNPDTNP--high compl (>15high compl (>15--33m)33m) 1.386E+10 2.348E+08 2.014E+08 7.356 1.011E+06 0.853

M/L KeysM/L Keys--patch reefpatch reef 9.295E+10 4.299E+08 0.00 0.000 3.473E+07 0.994

DTNP-low compl (>15-33m) 7.408E+09 2.923E+06 0.00 0.000 0.00 0.000

L Keys-forereef (6-15m) 1.288E+10 1.077E+08 0.00 0.000 2.091E+05 1.724

B/U Keys-forereef (>15-33m) 2.292E+09 1.079E+07 0.00 0.000 0.00 0.000

M/L KeysM/L Keys--forereef (<6m)forereef (<6m) 6.666E+08 4.947E+06 0.00 0.000 0.00 0.000

U/M KeysU/M Keys--forereef (6forereef (6--15m)15m) 2.375E+09 2.491E+07 0.00 0.000 5.398E+05 2.778

B/U KeysB/U Keys--forereef (<6m)forereef (<6m) 6.499E+08 2.262E+07 0.00 0.000 0.00 0.000

Population prevalence and total surface area estimates

Conclusions

Population-dynamic rates

Spatially explicit population metricsHabitat use

Sustainability metrics