Marine Sanctuaries Conservation Series MSD-03-1

U.S. Department of Commerce January 2003

National Oceanic and Atmospheric Administration

National Ocean Service

Office of Ocean and Coastal Resource Management

Marine Sanctuaries Division

Pre-Construction Coral Survey of the M/V Wellwood

Grounding Site

April 23-24, 2002
About the Marine Sanctuaries Conservation Series

The National Oceanic and Atmospheric Administration’s Marine Sanctuary Division (MSD)

administers the National Marine Sanctuary Program. Its mission is to identify, designate,

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series will facilitate integration of natural sciences, socioeconomic and cultural sciences,

education, and policy development to accomplish the diverse needs of NOAA’s resource

protection mandate.
Pre-Construction Coral Survey of the M/V Wellwood

Grounding Site

April 23-24, 2002

Steve Gittings, Science Coordinator

NOAA, Office of the National Marine Sanctuaries

Silver Spring, MD

January 2003

 

Silver Spring, Maryland

January 2003

U.S. Department of Commerce

Donald L. Evans, Secretary

National Oceanic and Atmospheric Administration

VADM Conrad C. Lautenbacher, Jr. (USN-ret.)

Under Secretary of Commerce for Oceans and Atmosphere

National Ocean Service

Jamie Hawkins, Acting Assistant Administrator

Marine Sanctuaries Division

Daniel J. Basta, Director
DISCLAIMER

Report content does not necessarily reflect the views and policies of the National Marine

Sanctuary Program or the National Oceanic and Atmospheric Administration, nor does the

mention of trade names or commercial products constitute endorsement or recommendation for

use.

REPORT AVAILABILITY

Electronic copies of this report may be downloaded from the National Marine Sanctuaries

Program web site at www.sanctuaries.nos.noaa.gov. Hard copies may be available from the

following address:

National Oceanic and Atmospheric Administration

Marine Sanctuaries Division

SSMC 4, N/ORM62

1305 East-West Highway

Silver Spring, MD 20910

COVER PHOTO CREDITS

Upper Left: The M/V Wellwood aground. Florida Keys National Marine Sanctuary.

Upper Right: Coral broken during the grounding. Florida Keys National Marine Sanctuary.

Lower Left: Restoration modules. Coastal Planning and Engineering Incorporated.

Lower Right: Map of restoration sites. Florida Keys National Marine Sanctuary.

CONTACT

Dr. Steve Gittings

National Science Coordinator

NOAA/National Marine Sanctuaries Program

N/ORM 62, SSMC-4, 11645

1305 East West Highway

Silver Spring, MD 20910

(301) 713-3125 X130

Steve.Gittings@noaa.gov

SUGGESTED CITATION

Gittings, Steve. 2002. Pre-Construction Coral Survey of the M/V Wellwood Grounding Site.

Marine Sanctuaries Conservation Series MSD-03-01. U.S. Department of Commerce, National

Oceanic and Atmospheric Administration, Marine Sanctuaries Division, Silver Spring, MD. 16

pp.
i

ABSTRACT

This report documents abundance and cover for selected elements of the benthic coral

reef assemblage at the site of the 1984 grounding of the M/V Wellwood on Molasses Reef,

Florida Keys. The purpose of the effort was to establish a pre-construction baseline before the

installation of reef modules at the site. The installation process is intended to stabilize fractured

substrates that were recently exposed by storm impacts, and to provide three-dimensional relief

in order to enhance reef community recovery. It is hoped that the restoration effort will result in

a biological assemblage with the character of the transition community that would exist there had

the incident not occurred. To date, the assemblage has developed the character of a

comparatively featureless hard ground similar in composition to hard ground areas and transition

zones surrounding the grounding site. These data will allow scientists and resource managers to

better track the trajectory of recovery following the installation of modules. Direct counts of

scleractinian and gorgonian corals, hydrocorals of the genus Millepora, and zoanthids of the

genus Palythoa were made in three areas within and around the grounding site. The site is

poorly developed with respect to scleractinian colony size and cover compared to surrounding

areas. Key scleractinian species necessary for the development of topographic relief in the area

denuded by the grounding are not well represented in the current community. Though gorgonian

cover and richness is similar in all study areas, gorgonian community recovery in the damaged

area is not complete. Unlike surrounding areas, one species, Pseudopterogorgia americana,

accounts for over half of all corals at the grounding site, over 80% of all gorgonians, and nearly

all the coral cover. Based on these findings and other observations made in the 18 years since

the grounding, recommendations are made that should be considered in the course of human

intervention targeted at stabilizing and enhancing the site.

KEY WORDS

Grounding, restoration, coral abundance, coral cover, recovery
ii

TABLE OF CONTENTS

Page

Abstract................................................................................................... i

Table of Contents....................................................................................... ii

List of Tables and Figures............................................................................. iii

Introduction............................................................................................. 1

Methods and Survey Areas............................................................................ 2

Findings.................................................................................................. 3

Discussion................................................................................................ 12

References................................................................................................ 15

Acknowledgements..................................................................................... 16
iii

LIST OF FIGURES AND TABLES

Page

Figure 1. Grounding Location of the Freighter M/V Wellwood.............................. 2

Figure 2. Abundance of Selected Benthic Organisms in Area Damaged..................... 4

Figure 3. Benthic Diversity in Survey Areas...................................................... 5

Figure 4. Mean Number of Taxa Per Quadrat in Three Areas................................. 6

Figure 5. Grounding Site Abundances 1986 and 2002........................................ 6

Figure 6. Hard Ground Abundances 1984-86 and 2002....................................... 7

Figure 7. Benthic Cover in Three Study Areas................................................... 8

Figure 8. Juvenile Corals............................................................................ 9

Table 1. List of Benthic Organism Colonies ................................................... 10

Table 2. Proportion of Abundance and Cover of Gorgonians and Benthic Space

Competitors Accounted for by Pseudopterogorgia americana................... 11

Figure 9. Evenness of Gorgonian Community in Three Study Areas......................... 12

1

INTRODUCTION

On August 4, 1984, the 122-m freighter M/V Wellwood ran aground on Molasses Reef, in

the Florida Keys National Marine Sanctuary. Damage to reef areas above approximately 8-m

depth was extensive, particularly at the final resting site of the vessel. Under the bow and

amidships, the broad tops of forereef spurs were destroyed and ground flat by the vessel’s hull,

and linear piles of boulders and coral fragments were formed as the bow plowed over the reef.

Nearly all corals were destroyed in an area totaling approximately 1500 m2

. Many corals and

sponges seaward of the final resting site were damaged or destroyed by cables used to haul the

vessel off the reef 12 days following the grounding.

Coral, algae, and fish surveys were conducted numerous times in the years following the

Wellwood grounding. Between 1984 and 1994, most data indicated that benthic community

succession at the grounding site resulted in a community more like that of nearby hard grounds

than the original transition zone assemblage that likely inhabited the location prior to the 1984

incident (Precht et al., 2001). Biological assemblages were dominated by a limited number of

gorgonian and scleractinian species with high recruitment rates (Gittings et al., 1993; Smith et

al., 1998). Gorgonian corals composed most of the cover. Very few framework building hard

corals had recruited to the site, and their slow growth precluded the development of pre-existing

topographic complexity, a factor vital to continued development of diverse invertebrate and fish

assemblages.

Storms in the late 1990s disrupted and/or removed significant portions of destabilized

reef framework from the grounding site, as well as attached benthic organisms. Restoration

activities planned for 2002 are intended to stabilize remaining at-risk surfaces and enhance

community development by the addition of topographic complexity and vertical structure.

Transplantation of selected coral species is also planned following the stabilization of the

substrate.

This survey was conducted to provide information on coral abundance and cover in the

area to be restored as well as reference areas nearby. The data establish a pre-construction

baseline in these communities and allow scientists and resource managers to track the trajectory

of recovery following enhancement. The purpose is to determine whether the restoration effort

will result in a biological assemblage with the character of the transition community that would

exist there had the incident not occurred or whether the assemblage continues to develop the

character of a hard ground.
2

METHODS AND SURVEY AREAS

Population and cover estimates were made in 18 one square meter quadrats in each of

three areas at and around the Wellwood grounding site (Figure 1). Estimates were made for all

observed species of scleractinian and gorgonian corals, hydrocorals of the genus Millepora, and

zoanthids of the genus Palythoa. Juvenile corals were considered those under 4 cm in diameter.

Because many small specimens were not identifiable in the field to species, some taxa were

identified only to genus. Percent cover estimates were made visually in the four quadrants of

each square meter quadrat, then averaged. Gorgonian cover within each quadrat was estimated

from above, equivalent to canopy cover for terrestrial vegetation.

WW

HG

TR

Area WW (Wellwood) was the flattened substrate created when the vessel ran aground.

Portions of this area were later removed by storms and are the target of restoration efforts. In

order to make later assessments of the effects of restoration activities within the site,

measurements were not made randomly. They were made in square meter quadrats in an

Figure 1. Grounding location of the freighter Wellwood, indicating areas of damage

and sampling sites occupied in 2002 (WW, HG, and TR; see text for descriptions).
3

alternating pattern along a transect running from the edge of one area to be restored across an

area to be left undisturbed to a second crater 25 m from the first.

Two “reference areas” were also surveyed near the grounding site:

• Area HG (hard ground) is an undisturbed area 25-50 m southeast of WW. It contains

a hard ground assemblage and limited relief. Surveys conducted since the grounding

showed that the recovering coral assemblage at the grounding site is becoming like

that of the hard ground (Precht et al., 2001).

• Area TR (transition zone) is an area that would have been forward (NNE) of the

Wellwood as it lay aground. It is a transition zone between former shallow Acropora

palmata stands and deeper hard ground assemblages. At the time of the grounding,

this area probably contained the type of assemblage destroyed by the grounding.

With the relief added to the grounding site by the addition of reef modules, it is expected

that the assemblage at the grounding site (corals, fish, etc.) will progress toward that of the

transition zone. Therefore, surveys were made in both hard ground and transition zone

environments surrounding the grounding site.

Measurements were not made in a shallower, high relief area to the west of the grounding

site even though they had been in surveys conducted between 1984 and 1990 (Area XBW of

Gittings, 1988 and Gittings et al., 1990, 1993). This is because the shallow water communities

in that area do not factor into the restoration objectives. That is, the objective of restoration is to

re-establish relief comparable to the transition zone that existed prior to the grounding of the

vessel, not that of the shallower zones nearby. Instead, surveys were conducted in Area TR.

FINDINGS

I. Community succession in the area denuded by the Wellwood has resulted in an

assemblage that is, for the most part, similar in composition to surrounding hard

ground areas and transition zones.

Figure 2 shows the abundance of gorgonians, scleractinians, and other significant benthic

space competitors (excepting algae) in the three areas surveyed. No sponges were encountered

in the quadrats. The grounding site and the transition zone averaged 28 colonies per square

meter. The hard ground area had approximately 32 colonies per square meter and a significantly

higher abundance of gorgonians than that in the transition zone (p=0.027, ANOVA). No other

significant differences in abundance existed among the areas.
4

WW TR HG

0

10

20

30

Scleractinians

Gorgonians

Hydrocorals

Palythoa

Benthic Populations

Area

Number/m2

*

*

Figure 2. Abundance of selected benthic organisms in the area damaged by the Wellwood

(WW), in an undamaged transition zone to the northeast of the grounding site (TR)

and in an undamaged hard ground community nearby (HG). Standard error bars are

shown. (* indicates where significant differences were found)

Richness of the dominant benthic taxa was also similar in all three areas surveyed (see

Figure 3), suggesting that recruitment has resulted in substantial recovery in the area damaged by

the Wellwood in 1984. Approximately 20 taxa (the range was from 19 to 21) were encountered

in each of the three areas surveyed.
5

WW TR HG

0

10

20

30

Total Taxa

Gorgonians

Scleractinians

Hydrocorals

Palythoa

Benthic Diversity

Area

Taxa in Surveys

Figure 3. Diversity, measured as the cumulative number of taxa encountered, of scleractinians,

gorgonians, zoanthids and hydrocorals in each of the survey areas.

While cumulative richness was similar in each area, the number of taxa per quadrat was

lower at the grounding site than at either reference site (Figure 4; p=0.014, ANOVA). The range

of the number of taxa in the samples, however, was similar for all areas (between 5 and 11 taxa).

Given the similarity in abundance estimates in all three sets of samples, it is not clear how to

explain this finding. It is possible that patchiness among individual species has resulted in

greater clustering in the grounding site, affecting local (i.e. small scale) richness.

Species that compose the recovering community at the grounding site are those found in

surrounding areas. Figures 5 and 6 show abundance data from a 1984-1986 study (Gittings,

1988) alongside the 2002 data for all species encountered in quadrats in the grounding site and

the hard ground area. Figure 5 shows considerable increases in abundance for several genera,

including Pseudopterogorgia, Gorgonia, Millepora, Porites, Agaricia, and Siderastrea.

Significantly, these genera are also dominant in the hard ground area (Figure 6) and present

abundances for most taxa are similar in both areas.
6

WW TR HG

0

2

4

6

8

10

Area

Taxa/m2

*

Figure 4. Mean number of taxa per quadrat (with standard error) in the three areas (n=18 for

each area). (* indicates where significant differences were found) AGSP DISP EUFA FAFR MIAL MOCA POSP SISP STMI BRAS ERCA EUSP GOVE MUSP PLSP PSEU

PSSPPTSP

0

2

4

6

8

1986

2002

Grounding Site Taxa

Number/m2

15.11

Grounding Site Abundances - 1986 and 2002

Figure 5. Abundances of species of scleractinians, gorgonians, hydrocorals, and zoanthids at the

grounding site of the M/V Wellwood in 1986 (Gittings, 1988) and in 2002 (this

assessment). Taxon codes are found in Table 1. Vertical line separates gorgonian

corals (right side) from other benthic taxa.
7

ACCE

ACPAAGSP

CONA

DICHDICL

DILA

DISR

EUFAFAFR

ISSI

MASP

MAAR

MEME

MIAL

MOAN

MOCA

MYSP

PALYPOSP

SCSP

SISP

SOSP

STMI

BRAS

ERCA

EUSP

GOVE

MUFLMUSP

PLSP

PSSPPTSP

0

2

4

6

8

1984-6

2002

Hard Ground Abundances 1984-86 and 2002

Hard Ground Taxa

Number/m2

18.0

Figure 6. Abundances of species of scleractinians, gorgonians, hydrocorals, and zoanthids found

in the hard ground area between 1984 and 1986 by Gittings (1988) and in 2002.

Taxon codes are those found in Table 1. Vertical line separates gorgonians (right side)

from other benthic competitors.

II. The grounding site is poorly developed with respect to scleractinian colony size and

cover compared to surrounding areas.

Coral cover data (Figure 7) show that the three areas surveyed have similar gorgonian cover,

averaging around 7%. Furthermore, total cover (ranging from 7 to 10%) did not differ

significantly among areas. Scleractinian cover, however, was very low in the damaged area,

accounting for almost none of the measurable cover in the 18 quadrats surveyed. Though high

variation among samples resulted in only a borderline significant difference between this and the

other areas (p=0.06), it is clear that scleractinian cover remains very low even after 18 years of

recovery from the impacts of the ship grounding.
8

WW TR HG

0

2

4

6

8

10

12

Gorg. Cvr

Scler. Cvr

Hydro. Cvr

Palythoa Cvr

Benthic Cover

Area

Percent Cover

Figure 7. Percent cover of gorgonians, scleractinians, hydrocorals, and zoanthids in the three

study areas.

The difference in scleractinian community development is evident in colony size data

(Figure 8). Nearly 70% of colonies encountered in the grounding area were less than 4 cm in

diameter (a size generally considered to represent juveniles). The remaining colonies were only

slightly larger. In the other areas, only 36% of colonies were less than 4 cm, and a large number

of substantially larger colonies were observed. It should be noted, however, that there are a few

larger scleractinians in the grounding area that survived the incident by being in depressions that

were not impacted by the hull of the vessel, but none of these were in the quadrats surveyed

during the 2002 site visit.
9

WW TR HG

0

20

40

60

80

Juvenile Corals

Area

Percent of Scleractinians

Figure 8. The proportion of scleractinian corals surveyed in each area that were less than 4 cm

in diameter and therefore considered to be non-reproductive juvenile colonies.

III. Scleractinian species required for the development of topographic relief in the area

denuded by the grounding are not currently well represented.

Of the 28 taxa in the 54 quadrats surveyed, 19 to 21 occurred in any single area (see Table 1).

Among scleractinians, it may be significant that certain species in the undamaged references

areas were not found at the grounding site. Specifically, frame-building species like

Montastraea faveolata, M. franksi, and Diploria spp. were absent from samples in the grounding

site, a finding consistent with previous studies here and at other grounding sites (e.g. Gittings et

al., 1990; Smith et al., 1998; Miller and Barimo, 2001). On the other hand, Siderastrea siderea,

which can also form large colonies, was present. These species are broadcast spawning corals,

which generally are found only rarely as recruits on reefs. Most recruits at the grounding site

brood larvae following internal fertilization, resulting in considerably more localized

recruitment. This may account for the differences in abundance among species. It should also

be noted that even in the reference areas, the abundance of frame-building species was low, and

all three areas were dominated by small colonies of species in the genera Agaricia and Porites,

few of which typically contribute substantially to habitat relief.
10

Table 1. Benthic organisms in survey areas (number of colonies/m2

, rounded to the nearest 0.1)

examined between 1984 and 1986, or in 2002. Codes for each species refer to those in Figures 5

and 6. Blank cells indicate that the species was not encountered.

TAXA Wellwood

(WW)

Transition

Zone (TR)

Hard Ground

(HG)

1986 2002 2002 1984-

6 2002

Scleractinians

Acropora cervicornis (ACCE) 0.0

Acropora palmata (ACPA) 0.0

Agaricia spp. (AGSP) 0.3 1.5 3.1 1.6 2.6

Colpophyllia natans (CONA) 0.0

Dichocoenia stokesii (DICH) 0.2 0.9 0.1

Diploria clivosa (DICL) 0.0

Diploria labrynthiformes (DILA) 0.1 0.0 0.1

Diplora strigosa (DISR) 0.0

Diplora spp. (DISP) 0.1

Eusmilia fastigiata (EUFA) 0.1 0.1 0.0

Favia fragum (FAFR) 0.4 0.1 0.1 0.1 0.1

Isophyllia sinuosa (ISSI) 0.0

Leptoseris cucullata (LECU) 0.1 0.2

Madracis sp. (MASP) 0.0 0.1

Manicina areolata (MAAR) 0.0

Meandrina meandrites (MEME) 0.0 0.1

Montastraea cavernosa (MOCA) 0.1 0.4 0.1 0.4 0.1

Montastraea annularis complex

(MOAN)

0.2 0.2

Mycetophyllia sp. (MYSP) 0.0

Porites spp. (POSP) 0.3 1.8 1.2 0.7 2.6

Scolymia sp. (SCSP) 0.0

Siderastrea radians (SISP) 0.4 0.2

Siderastrea siderea (SISP) 1.3 0.7 0.4

Siderastrea spp. (SISP) 0.8

Solenastrea spp. (SOSP) 0.0 0.1

Stephanocoenia michelini (STMI) 0.1 0.0 0.1

Gorgonians

Briareum asbestinum (BRAS) 0.1 0.1 0.9 1.4 1.3

Erythropodium caribaeorum

(ERCA)

0.1 0.1 0.9

Eunicea spp. (EUSP) 0.2 0.1 0.6

Gorgonia flabellum (GOFL) 0.1

Gorgonia ventalina (GOVE) 0.1 2.1 0.8 0.2

Muricea spp. (MUSP) 0.1 0.0
11

TAXA Wellwood

(WW)

Transition

Zone (TR)

Hard Ground

(HG)

1986 2002 2002 1984-

6 2002

Plexaura spp. (PLSP) 0.1 0.1 0.3 0.2 1.0

Pseudoplexaura spp. (PSEU) 0.1

Pseudopterogorgia americana

(PSSP)

1.4 14.6 12.4 7.1 17.0

Pseudopterogorgia bipinnata

(PSSP)

0.5 1.2 1.0

Pterogorgia spp. (PTSP) 0.1 0.6 0.0 0.2

Hydrocorals

Millepora spp. (MIAL) 0.8 4.2 3.8 3.7 4.0

Zoanthids - Colonial anemones

Palythoa spp. (PALY) 0.4 1.8 0.1 0.3

Total Number of Taxa 12 19 21 31 20

IV. Though gorgonian cover and richness is similar in all study areas, gorgonian

community recovery in the damaged area is not complete.

Among the gorgonians, all areas were dominated by the sea plume Pseudopterogorgia

americana, both in terms of abundance and cover, with the most disproportionate population

occurring in the grounding area. Table 2 shows that roughly half of all benthic colonies in each

area were P. americana, and nearly all gorgonian cover is accounted for by this species. Figure

9 shows that the apportionment of individuals among gorgonian species (i.e., evenness) is lowest

in the grounding area, a fact that is explained by the higher proportion of P. americana relative

to other species. Lower diversity measures in the grounding area suggest that even though

gorgonian cover is similar among the sites, gorgonian community development has still not

recovered completely in the grounding area.

Table 2. Proportion of abundance and cover of gorgonians and all benthic space competitors

accounted for by Pseudopterogorgia americana.

Pseudopterogorgia americana as a

percent of:

Wellwood

(WW)

Transition

Zone (TR)

Hard Ground

(HG)

Gorgonian Colonies 82 75 79

Gorgonian Cover 99 99 92

All Benthic Colonies 52 45 53

All Benthic Cover 97 66 83
12

WW TR HG

0.0

0.1

0.2

0.3

0.4

0.5

Gorgonian Evenness

Area

Evenness

Figure 9. Evenness of gorgonian community in the three study areas. Evenness was measured

as H’/ln(S), where H’ is Shannon-Weaver species diversity and S is the number of taxa

observed.

DISCUSSION

The casual observer swimming over the Wellwood grounding site would most likely not

recognize it as having been disturbed. It is clearly a low relief area that is quite different in

character from what it was prior to the grounding, but not knowing that, the observer would find

it similar in appearance to hard ground areas nearby. Coral cover, diversity, and abundances are

all similar to those in surrounding communities with similar relief. Dr. Margaret Miller, who

surveyed the site in 1999, has a largely similar impression of the current status of the site

(unpubl. data, pers. comm.).

It is only with detailed examination of the species assemblages that one can distinguish

the grounding site from other areas at similar depth. A good observer might notice the lack of

large corals in the grounding area, but the aerial extent of the flattened reef is small enough that

larger colonies beyond the area might be visible, leaving few signs of the location’s uniqueness.

Nevertheless, the grounding site has certainly not recovered its original character, which

was that of a transitional area between a shallow, Acropora palmata dominated zone and a

slightly deeper hard ground assemblage. It contained moderate to high relief (see Precht et al.,

2001) and diversity. While species diversity and population levels are currently close to those of

transition zone and hard ground assemblages in the vicinity, cover of hard corals and the

populations of certain key species necessary for continued structural development are lacking.
13

As has been noted previously, natural recovery of topographic relief at the grounding site

of the Wellwood will take decades (Gittings, 1988; Gittings et al., 1990, 1993; Precht et al.,

2001). Data from this survey show that even two decades of biological production has not been

enough to create noticeable relief at the site. This limits the potential for recovery of other

assemblages that depend on vertical relief and habitat complexity, including fish and benthic

infauna (Szmant, 1997; Ebersole, 2001; Precht et al., 2001).

On the other hand, physical processes have created substantial relief at the site. Storms

during the last several years have mobilized framework originally loosened by the grounding,

excavating depressions more than a meter deep and several meters in diameter. The result is a

habitat with greater complexity than existed at any time since the grounding, and with newly

available interstices and vertical relief. While very little coral growth currently exists on the

exposed reef rock, it is likely that one to two decades of recruitment would result in populations

comparable to surrounding undamaged areas.

Unfortunately, there may be additional reef material that was destabilized by the

grounding. Future storms would be likely to interrupt community development by further

excavating the damaged area and causing collateral damage. Stabilization of these areas may

help deter such events, but care should be taken to limit to the extent possible the loss of recently

created habitats during upcoming restoration efforts.

Where extensive concrete addition is required, attempts should be made to maintain as

high a structural complexity as possible, particularly microhabitat complexity. During this

survey, counts in a 1m2 quadrat on top of a smooth concrete slab poured soon after the grounding

(H. Hudson, pers. comm.) yielded the lowest abundances of any made during the visit. Coral

abundances were only 54% of the mean elsewhere in the area (56% for gorgonians and 36% for

scleractinians). Cover was only 15% of the area mean. A large number of fish bites (scrape

marks) were visible on the slab, suggesting that fish may limit coral recruitment on such

surfaces. This may be because the flat surfaces are more easily accessible than the complex

surfaces of natural reef material. High microhabitat structural complexity in framework restored

by humans may be necessary to limit grazing effects on recruitment.

Transplantation work will follow construction efforts directed at stabilizing substrate and

increasing three-dimensional structure. It should be recognized that most, if not all, the species

present in undamaged zones adjacent to the grounding are also present at the grounding site

itself. Nearly all have recruited since 1984, but some are adults that survived the grounding and

remain in place. Thus, the objective of transplantation need not be to ensure full diversity at the

grounding site. More appropriate would be to transplant large adult colonies of species that are

important habitat creators, such as the Montastraea annularis and Diploria spp. complexes. This

may help restore a more natural appearance to the area as well as serve a function in generating

attractive habitat for fish and benthic organisms (see Spieler et al., 2001). With regards to

gorgonian transplantation, it is recommended that species selected be those that are rare in the

damaged area compared to surrounding hard ground and transition areas. These include

Briareum asbestinum, Plexaura spp. and Pterogorgia spp. While these will not significantly

enhance topographic aspects of the environment, they will increase complexity and diversity

within the restored area, improving its appearance. Large Gorgonia ventalina sea fans would
14

have a similar effect, but they currently appear to be fairly rare in the vicinity of the grounding

site. In fact, more G. ventalina were found in the grounding site than in surrounding habitats

during the survey, though all were very small specimens.

The grounding site and the restoration efforts also provide an opportunity to employ new

methods of restoration that may enhance the rate or quality of community recovery. The

addition of sea urchins such as Diadema antillarum could reduce algae competition and enhance

coral growth. Techniques could also be used to enhance the settlement of corals, including the

use of chemical attractants (Morse et al., 1994) and seeding of the reef or reef modules with

larvae taken from adult corals (Szmant, 1997) during spawning episodes.
15

REFERENCES

Ebersole, J.P. 2001. Recovery of fish assemblages from ship groundings on coral reefs in the

Florida Keys National Marine Sanctuary. Bull. Mar. Sci. 69(2): 655-671.

Gittings, S.R. 1988. The recovery process in a mechanically damaged coral reef community.

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ACKNOWLEDGMENTS

My thanks go to Bill Valley for making the field work possible, to Margaret Miller for

providing data from previous visits to the Wellwood site, to Harriet Sopher and Lisa Symons for

offering up the opportunity, and to Lynn Takata for assistance with the manuscript.