Survey of Benthic Macroinfauna and Levels of Chemical Contaminants in 

Sediments and Biota at Gray’s Reef National Marine Sanctuary 

(FY01 Annual Report for the 2000-2002 Site Characterization Study of Gray’s Reef National 

Marine Sanctuary) 

September 2001 

Submitted by 

Jeffrey Hyland, Cynthia Cooksey, Leonard Balthis, Geoff Scott, and Daniel Bearden 

NOAA National Ocean Service, National Centers for Coastal Ocean Science, 219 Fort Johnson 

Road, Charleston, SC 29412-9110 

Submitted to 

Gray’s Reef National Marine Sanctuary Office 

NOAA National Ocean Service 

Office of National Marine Sanctuaries 

10 Ocean Science Circle 

Savannah, GA 31411 

NOAA  National Ocean Service  National Centers for Coastal Ocean Science 

NAT OI NALOCEAN IC AND ATMOSPHER IC ADM IN ISTRATIO

U

N

.S .DEPA RTMENT O F COMMERCE
2

1. Introduction 

A study is being conducted to assess the condition of 

benthic macroinfauna and contaminant levels in 

sediments and biota of the Gray’s Reef National Marine 

Sanctuary (GRNMS) and nearby inner-shelf waters off 

the coast of Georgia. Benthic research in the sanctuary by 

previous investigators has focused largely on live-bottom 

assemblages associated with rocky outcrops (Fig. 1). In 

contrast, there has been limited work on the ecology of 

unconsolidated sandy substrates which surround the 

rocky-reef structures and characterize much of the innershelf area in the general vicinity of Gray’s Reef. The 

present study is providing a first-ever quantitative 

baseline on levels of potential environmental 

contaminants and condition of the infaunal organisms 

living within these substrates. The soft-bottom benthos is 

a key component of coastal ecosystems, playing vital 

roles in detrital decomposition, nutrient cycling, and 

energy flow to higher trophic levels. Moreover, because 

of their relatively stationary existence within the 

sediments, benthic infauna (Fig. 2) can serve as reliable 

indicators of potential environmental disturbances to the 

seafloor. Such information is of direct importance to the development of management plans for 

the Sanctuary, as a contribution to our understanding of the overall ecology of this system and as 

a baseline for monitoring any future changes due to either natural or anthropogenic influences. 

The present benthic survey is a 

component of a larger, ongoing 

coordinated site characterization of 

the sanctuary by the GRNMS 

Office and three NCCOS Centers 

(CCMA, CCFHR, and CCEHBR). 

2. Objectives and Scope 

The study is designed around a twoyear field effort with one sampling 

event in each year. The first cruise 

was conducted April 3-7, 2000 

(NOAA Ship FERREL Cruise FE00-06-GR) and the second was 

conducted April 29-May 5, 2001 

(NOAA Ship FERREL Cruise FE01-08-MA: Leg 1). Cruise reports 

are available upon request (email 

<jeff.hyland@noaa.gov>). 

Figure 1. Live bottom habitat at Grays Reef

National Marine Sanctuary. Photo courtesy 

of Karen Angle.

Figure 2. Examples of benthic macroinfaunal at GRNMS.
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Objectives of the first year of sampling were to: (1) assess baseline condition of macroinfauna 

(> 0.5 mm), concentrations of chemical contaminants in sediments, and contaminant bodyburdens in target benthic species within the sanctuary boundaries; and (2) provide a quantitative 

basis for tracking potential changes in these properties with time due to either natural or human 

events. To address Year-1 objectives, 20 stations were established all within the sanctuary 

boundaries (Figs. 3 and 4). A random sampling design was applied to support probability-based 

estimates of the percentage of area with degraded versus non-degraded condition relative to 

various measured environmental indicators. The resulting sampling framework is a 58-km2 grid 

of 20 individual cells, each of which is 2.9 km2

, and which together are representative of the total 

area of the sanctuary (Fig. 4). One station was randomly located within each cell. 

At each of the 20 Year-1 stations, samples were collected for characterization of general habitat 

conditions (depth, temperature, salinity, pH, DO, TOC, grain size), concentrations of sediment 

contaminants (metals, pesticides, PCBs, PAHs), diversity and abundance of macroinfauna (> 0.5 

mm), and aesthetic quality (presence of anthropogenic debris, visible oil, noxious sediment odor, 

and water clarity based on secchi depths). Target benthic species (the turkey wing arc shell Arca

zebra and black sea bass Centropristis striata) also were collected in selected areas (by divers for 

the molluscs and by fish traps for the bass) and analyzed for contaminant levels in tissues. 

Figure 3. Sampling design for benthic survey.
4

The second year of sampling included additional sites outside the sanctuary in nearby inner-shelf 

areas (Fig. 3). Sampling was conducted at a total of 20 stations: three cross-shelf transects of 

five stations each, including one station in Grays Reef serving as the seaward end of the middle 

transect, and an additional five stations within the sanctuary boundaries. The three cross-shelf 

transects provide the means to examine spatial patterns in benthic communities and sediment 

contaminant levels in relation to both natural factors (e.g., depth) and potential anthropogenic 

factors (e.g., proximity to land-based sources of contaminants). An important goal here is to 

determine the extent to which land-based sources of pollutants and other materials are 

transported through river systems to the offshore shelf environment, inclusive of GRNMS, and 

the potential effects that these materials may have on biological resources along the way. Nearfield versus far-field comparisons at similar offshore depths as the sanctuary (focusing on 

outermost stations along the three transects) are being used as well to test for additional patterns 

in biological resources in relation to reef proximity (including, for example, potential biological 

interactions such as predation effects from foraging by reef species). Sampling also was 

conducted at six of the previous Year-1 stations within the sanctuary boundaries, including the 

outermost station along the middle transect, to provide a basis for examining potential betweenyear temporal variability. 

At each of the 20 

Year-2 stations, as 

before, samples were 

collected for 

characterization of 

diversity and 

abundance of benthic 

fauna, concentration 

of sediment 

contaminants, general 

habitat parameters 

(depth, temperature, 

salinity, TOC, grain 

size), and aesthetic 

quality (presence of 

debris, oil slicks, 

noxious sediment 

odor, and water 

clarity based on 

secchi depths). 

Bottom trawls for 

demersal fishes and 

macroinvertebrates 

and bongo nets for 

ichthyoplankton also were taken opportunistically at each of the cross-shelf transect sites as part 

of a companion survey conducted by the NOAA CCFHR. The two synoptic data sets will be 

compared to examine predator-prey relationships and other potential benthic-pelagic interactions. 

Figure 4. Site locations within GRNMS. The random sampling framework allows 

unbiased statistical estimation of the percentage of area with degraded vs. nondegraded condition relative to various measured environmental variables. Each cell 

= 2.9 km2

. 
5

3. Current Progress and Preliminary Findings 

All field sampling for this project has been completed. Samples from the recent Year-2 survey 

(April 29-May 5, 2001) are still being processed and resulting data will be presented in an 

overall final report in fall 2002. The following description of conditions within the sanctuary is 

based on data from the analysis of Year-1 samples collected April 3-7, 2000. 

Key habitat characteristics 

within the sanctuary (Fig. 5) 

consist of: (1) inner-shelf 

depths, typically between 17-

20 m (full range was 14.5-

21.1 m); (2) euhaline 

(oceanic) salinities around 34 

ppt; (3) very high DO levels 

around 8 mg/L, which are well 

above a reported benthic 

hypoxic effect threshold of 

about 1.4 mg/L (Diaz and 

Rosenberg 1995) as well as 

most State standards of 5 

mg/L or lower; (4) low levels 

of organic carbon in 

sediments, typically between 

1-2 mg/g; and, (5) coarse 

sediments consisting mostly of sand with some shell hash and gravel-size particles. There was 

no fine (silt-clay) fraction of sediment apparent in these samples. The coarse (> 62 micron) 

fraction comprised 99-100% of the sediment at all stations. A more detailed record of these 

variables by station is presented in Appendix A. 

Appendix B lists means and ranges in concentrations of various chemical contaminants measured 

in this study (i. e., pesticides, PAHs, PCBs, and metals) and, where available, corresponding 

sediment quality guidelines (SQG) for interpreting the biological significance of the observed 

contaminant levels. Two types of SQGs are included: (1) Effects Range-Low (ERL) and Effects 

Range-Median (ERM) values of Long et al. (1995, updated from Long and Morgan 1990); and 

(2) Threshold Effects Level (TEL) and Probable Effects Level (PEL) values of MacDonald et al. 

(1996). ERL and TEL values are both lower-threshold bioeffect limits, below which adverse 

effects of the contaminants on sediment-dwelling organisms are not expected to occur. In 

contrast, ERM and PEL values both represent midrange concentrations of chemicals above 

which adverse effects are more likely to occur. Concentration-to-SQG comparisons were based 

on the lower ERL and upper ERM values for most chemicals (see appendix); in some cases, 

however (e.g., where updated ERL and ERM values were not available), the alternative TEL and 

PEL values were used. 

Figure 5. Key habitat characteristics at GRNMS in April 2000 (n = 20 

sites). Boxes are interquartile ranges, horizontal lines within boxes are 

medians and wisker endpoints are high/low extremes. Note in the last plot 

that values of % sand-gravel fall within a very narrow range of 99-100%.
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Sediments were fairly clean with respect to presence of chemical contaminants. Ninety-five % 

of the area of the sanctuary had sediments with all measured contaminants below corresponding, 

lower-threshold ERL/TEL guidelines (Fig. 6). There were no stations with “high” levels of 

contamination — defined here as one or more contaminants present at concentrations above 

upper-threshold ERM/PEL guideline values, or multiple (three or more) contaminants present at 

moderate concentrations between these lower and upper bioeffect thresholds. One station, 

representing just 5% of the sanctuary’s area, had a moderate concentration of copper (103 g/g) 

that was above the lower-threshold ERL guideline value of 34 g/g, but still below the higher 

ERM value of 270 g/g. Though the source could be natural or anthropogenic, the concentration 

of copper at this station was higher than the concentrations typically observed in other 

southeastern coastal areas remote from contaminant sources (Windom et al. 1989). 

In comparison to 

conditions at Gray’s Reef, 

sediment contamination in 

neighboring estuaries is 

much higher (Fig. 6). For 

example, based on data 

from 252 sites sampled 

throughout southeastern 

estuaries from 1994-97, as 

part of the Environmental 

Monitoring and 

Assessment Program 

(EMAP), it can be 

estimated that 24% of the 

area of this region has 

high sediment 

contamination (J. Hyland, 

unpublished data). This 

percentage is obviously 

higher than the zero % 

incidence observed presently within the sanctuary. Another 15% of southeastern estuaries had 

moderate levels of contamination. 

The generally low levels of sediment contamination throughout the sanctuary is a satisfying 

result from a resource-management perspective. Yet it is important to recognize that man-made 

pesticides (DDT, chlorpyrifos) and other chemical substances directly associated with human 

activities (PCBs, PAHs) were detectable in these sediments, though not at concentrations likely 

to cause significant bioeffects (see Appendix B). Their presence even at trace concentrations 

provides direct evidence that such materials are capable of reaching the offshore sanctuary 

environment, either by atmospheric fallout or cross-shelf transport from land. It is especially 

interesting that this list includes a relatively non-persistent pesticide like chlorpyrifos. 

Appendix C lists means and ranges in contaminant concentrations measured in the tissues of two 

bottom-dwelling organisms, black sea bass Centropristis striata and the turkey wing ark shell 

Figure 6. Comparison of sediment contamination (% area) at GRNMS during 

the present study vs. southeastern estuaries sampled during EMAP (unpublished 

data from senior author). 
7

Arca zebra. FDA 

human-health 

guidelines (either action 

levels or levels of 

concern) are included 

where available for 

comparison. There 

were no exceedances of 

the FDA guideline 

values in any of these 

19 samples (10 

individual fish fillets 

and 9 arc-shell 

composites). Moderate 

concentrations of lead, 

however, just below the 

Level of Concern value 

of 3 μg/g dry weight, 

were found in one fish sample (2.6 μg/g) and one arc-shell sample (2.9 μg/g). Similar to results 

for sediments, tissues of both species contained trace concentrations of additional man-made 

pesticides (DDT, chlorpyrifos, dieldrin, lindane, heptachlor epoxide) and other chemical 

substances associated with human sources (PCBs, PAHs). The fact that immobile organisms like 

the arks are picking up these contaminants, albeit at low concentrations, is further evidence that 

such materials are making their way to the offshore sanctuary environment, either by air or 

underwater cross-shelf transport. 

The benthic infauna inhabiting sandy substrates within the sanctuary are comprised mostly of 

polychaete worms, molluscs, and arthropods (Fig. 7). These three major taxonomic groups 

Figure 7. Relative composition of major taxonomic groups of macroinfauna at 

GRNMS. Data based on 3 replicate grabs (0.04 m2

) at each of 20 stations. 

Table 1. Dominant macroinfaunal species at GRNMS contributing to >= 1% of total species 

abundance individually and to 75% of cumulative % abundance collectively. 

Taxon Group 

Average 

Density 

(#/m2

) 

% of Total 

Abundance 

Cum % 

Abundance 

% Station 

Occurrence 

Ervilia sp. A* Bivalve 4938 55.9 55.9 75 

Caecum johnsoni Gastropod 301 3.4 59.3 95 

Crassinella lunulata Bivalve 268 3.0 62.4 100 

Branchiostoma spp. Chordate 251 2.8 65.2 95 

Aspidosiphon muelleri Sipunculid 218 2.5 67.7 95 

Spiophanes bombyx Polychaete 164 1.9 69.5 100 

Spio pettiboneae Polychaete 158 1.8 71.3 100 

Oxyurostylis smithi Cumacean 155 1.7 73.0 100 

Ophiuroidea Ophiuroid 125 1.4 74.5 90 

Actiniaria Anthozoan 102 1.2 75.6 80 

* Possible new subspecies of Ervilia concentrica. 
8

represent 90% or more of the fauna, both by percentage of species and abundance. The 

dominant (10 most abundant) taxa were the bivalves Ervilia sp. A and Crassinella lunata; 

gastropod Caecum johnsoni; chordate Branchiostoma spp. (lancelets); sipunculid Aspidosiphon 

muelleri; polychaetes Spiophanes bombyx and Spio pettiboneae; unidentified ophiuroids; and 

unidentified actiniarian anthozoans (Table 1). The abundance of each of these 10 taxa was at 

least 1% of the total faunal abundance and their cumulative abundance accounted for 75.6% of 

total abundance. All 10 taxa also exhibited a very high frequency of occurrence, each being 

present in at least 75% of the samples. 

The top dominant taxon at Gray’s Reef was Ervilia sp. A, which represented 55.9% of the total 

abundance and occurred in 75% of the samples (Table 1). Its presence is important in that the 

specimens may represent a new subspecies of Ervilia concentrica. In addition, Ervilia is very 

important from a trophic perspective. Sedberry (1985), for example, reported that the largest 

percentage by number (38%) of prey consumed by tomtate, Haemulon aurolineatum, in the 

South Atlantic Bight consisted of Ervilia. Another dominant infaunal species occurring at 

Gray’s Reef, the lancelet Branchiostoma spp., was reported by Sedberry as representing the 

largest volume (41.6%) of 

prey consumed by tomtate. 

The dominant species in 

Table 1 are very different 

from the list of dominant 

(10 most abundant) 

invertebrate species 

collected at Gray’s Reef 

during an earlier (1980-

81) MMS-sponsored 

survey of living marine 

resources of the south 

Atlantic OCS (MRRI 

1982). Eight of the 10 

dominant species found 

during the MMS survey 

were crustaceans 

(Luconacia incerta, 

Elasmopus sp. A, 

Erichthonius brasiliensis, 

Lembos smithi, Caprella 

equilibra, Podocerus sp., 

Photis sp., and 

Leptochelia sp.) and the 

remaining two were 

polychaetes (Lumbrieris 

inflata and Polycirrus 

carolinensis). None of 

these species were among 

Table 2. Characteristics of benthic macroinfaunal (> 0.5mm) at 

stations sampled in GRNMS, April 2000. Three replicate grabs 

(0.04m2 each) were taken at each station. 

Station Mean No. Taxa 

(per grab) 

Total No. 

Taxaa

Mean Density 

(No./m2) 

H ́

Diversityb

1 32 66 2542 4.96 

2 58 113 5775 5.11 

3 53 102 5217 5.25 

4 52 96 4492 5.29 

5 57 98 4083 5.61 

6 31 62 2617 4.39 

7 32 57 2233 4.86 

8 59 117 9850 4.28 

9 41 84 3125 5.16 

10 64 115 7967 4.82 

11 34 71 6650 2.37 

12 49 96 5933 4.52 

13 40 81 40642 0.82 

14 45 89 50258 0.71 

15 46 94 4300 4.78 

16 27 53 1642 4.88 

17 42 80 3608 3.59 

18 41 85 5900 3.64 

19 47 91 1858 4.91 

20 45 86 423 5.32 

a. Grand total from all 20 stations = 349 taxa. 

b. Calculated using base 2 logarithms. 
9

the list of dominants collected in the present study (though some occurred at lower densities as 

subdominants). Also, the abundant and trophically important Ervilia sp. A and Branchiostoma

spp. noted above were absent in the MMS study. This contrast in faunal composition between 

studies is due largely to differences in sampling approaches. During the MMS study, for 

example, divers used suction samplers to collect macroinvertebrates from veneers of sand closely 

associated with live-bottom outcrops and avoided large open patches of sand that were the focus 

of the present study. In addition, sampling at Gray’s Reef during the MMS study was conducted 

over a limited area at a single station (IS02), while the present study was conducted at multiple 

stations intended to be more representative of the total area of the sanctuary. 

The macroinfaunal assemblages of Gray’s Reef are highly diverse. From just this one sampling 

occasion (60 individual, 0.04 m2 grab samples) a total of 349 different species were identified 

(Table 2). The total number of species found at each station (based on three grabs per station) 

ranged from 53 to 117. Mean number of species per replicate sample ranged from 27 to 64 and 

mean H' diversity ranged from 0.71 to 5.61. Van Dolah et al. (1997) reported a similarly high 

diversity of macroinfauna, with mean numbers of species ranging from 34 to 70 species/0.04m2

, 

in a study conducted with comparable methods in inner-shelf sands off the coast of South 

Carolina. Although a difference in methods precludes direct comparisons, the earlier MMS 

sampling at Gray’s Reef also showed a high diversity of macroinvertebrates in sandy substrates 

interspersed among live-bottom (MRRI 1982). 

The high diversity of 

benthic fauna at Gray’s 

Reef is further 

illustrated in Fig. 8, 

which compares mean 

number of species, H', 

and abundance per grab 

at sanctuary sites to 

these same attributes at 

sites of similar salinity 

sampled throughout 

southeastern estuaries as 

part of EMAP (J. 

Hyland, unpublished 

data). Typically, the 

two measures of 

diversity (number of 

species and H') were 

about twice as high as 

those associated with 

the neighboring 

estuaries. Inter-quartile ranges for both measures were much higher and did not overlap with the 

estuarine sites. Abundances were about the same. 

Figure 8. Comparison of benthic species richness, diversity and abundance at 

GRNMS sites (n = 20) vs. estuarine sites of similar salinity (> 30 ppt) in EMAP 

Carolinian Province (n = 38). Boxes are interquartile ranges, horizontal lines 

within boxes are medians and wisker endpoints are high/low extremes. Base 2 

logarithms were used to calculate H ́.
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These results serve as a basis to put aside a frequent misconception that the wide expanses of 

“featureless” sandy bottom surrounding live-bottom outcrops within the sanctuary are a 

“biological desert” and that diverse and abundant marine life occur only where hard bottom is 

emergent. Such a pattern may be true for assemblages of larger and more visible epifaunal 

species that require hard substrates for attachment. However, there are highly diverse and 

abundant assemblages of infaunal organisms inhabiting the unconsolidated sands that 

characterize much of the surrounding seafloor. These fauna are important as major prey to 

higher trophic levels and serve other vital roles in the ecology of the Gray’s Reef ecosystem. 

4. Implications for Coastal Management 

Data from the initial April 2000 survey suggest that contaminants in sediments and biota 

generally are at background reference levels, below probable-effect sediment quality and human 

health guidelines. Moreover, highly diverse and abundant macroinfaunal assemblages were 

observed at most stations throughout the sanctuary. These results, together with the absence of 

historical development of this portion of the OCS, provide reasonable evidence for suggesting 

that the sanctuary is currently in “good health” with respect to sediment quality and biotic 

integrity of the benthos and that present conditions can be used as a baseline for tracking any 

future changes. The presence of trace concentrations of pesticides, PCBs, and PAHs in both 

sediments and biota demonstrates that chemical substances from human sources are capable of 

reaching the offshore sanctuary environment and thus should be monitored to ensure that future 

problems do not develop. 

The ability to monitor potential changes relative to present baseline conditions is greatly 

facilitated by the probabilistic sampling design used in this study. As noted earlier, the sampling 

framework consisted of a population of 20 cells, each of which contained a randomly selected 

station, and which together are representative of the total area of the sanctuary. Under this 

design, each sampling point (station) is a statistically valid probability sample. Thus, 

percentages of the sanctuary with degraded vs. non-degraded environmental condition relative to 

selected indicators can be estimated based on conditions observed at individual sampling points. 

The percentage of overall degraded area, for example, can be computed by dividing the summed 

areas of individual cells in which impacts were observed by the total area of the sanctuary. 

Statistical confidence intervals around these estimates can be calculated as well. 

Figure 9 further illustrates how one might use these data to monitor potential changes in 

sediment quality with time. In this example, a combination of benthic species richness and 

sediment contamination is selected as an indicator of sediment quality. Criteria for evaluating 

high vs. low sediment contamination follows those defined earlier in Fig. 6. In addition, a 

threshold value of < 30 species/grab is suggested here as a criterion for evaluating potentially 

“degraded” vs. “non-degraded” condition with respect to species richness. Note that this specific 

value was derived by selecting a number just below the lower 10th percentile point from the 

cumulative frequency distribution of species richness values measured presently at Gray’s Reef 

sites. Because we are assuming these data to be representative of baseline reference conditions, 

this value can be regarded as a lower reference-range limit. Lower reference-range limits 

derived in the same fashion for H' and density, although not included in Fig. 9, were < 0.80/grab 

and < 2000/m2

, respectively. 
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Having defined evaluation criteria for both sets of variables, one can now estimate the 

percentage of area within the sanctuary that showed co-occurring evidence of an impaired 

benthos and contaminated sediments. Combining measures in such a “weight-of-evidence” 

approach has been shown to be a very effective tool for assessing pollution-induced degradation 

of the benthos (Chapman 1990). Figure 9 shows that in the Year 2000, zero % of the sanctuary 

area had low species richness (indicative of a potentially impaired benthos) accompanied by high 

sediment contamination. 

With the baseline established, one can then address the final question of how the condition of the 

sanctuary with respect to these variables is changing with time. The size of the change relative 

to some pre-determined set of management action criteria (such as the ones chosen arbitrarily in 

Fig. 9) provides a basis for deciding whether or not to apply specific mitigation measures. 

Selection of specific management action criteria should be based on a consensus of agreement 

among cognizant managers, science advisors, and stakeholders. However, regardless of what 

criteria are selected, the goal is to use this information as a basis for identifying the onset of a 

potential problem and whether the size of the affected area is growing so that corrective actions 

can be taken before the problem becomes too severe. Similarly, this information can be used to 

track recovery of potentially impacted areas to background conditions. As human activities in 

coastal regions continue to grow, it would be prudent to incorporate such approaches to help in 

identifying and managing potential environmental pressures that could follow. 

Figure 9. Examples of how probability-based sampling data could be used to monitor potential changes in 

sediment quality with time at GRNMS. Y-axis is % area exhibiting poor sediment quality, as indicated by 

combined evidence of low benthic species richness (e.g., < 30 species/grab) accompanied by high sediment 

contamination (e.g., 1 ERM or  3 ERL exceedances). 
12

5. Conclusions 

In general, chemical contaminants in sediments throughout the sanctuary are at background 

levels, below probable bioeffect guidelines. A low-level spike of copper, between 

corresponding lower- and upper-threshold ER-L and ER-M sediment quality guideline 

values, was observed at one station. Also, trace concentrations of man-made pesticides 

(DDT, chlorpyrifos) and other chemical substances from human sources (PCBs, PAHs) were 

detected in these sediments, though not at concentrations likely to cause significant 

bioeffects. The low sediment contamination is most likely attributable to the remote location 

of this offshore environment and the sandy nature of the substrate (e.g., absence of a silt-clay 

fraction). 

Contaminants in tissues of target benthic species are below human-health guidelines (where 

available) based on a limited sample population (10 fillets of black sea bass and 9 arc-shell 

composites). Moderate concentrations of lead, however, just below the FDA Level of 

Concern value of 3 μg/g dry weight, were found in one fish sample (2.6 μg/g) and one arcshell sample (2.9 μg/g). Similar to results for sediments, tissues of both species contained 

trace concentrations of additional chemical contaminants associated with human sources 

(pesticides, PCBs, PAHs), further demonstrating that such materials are making their way to 

the offshore sanctuary environment, either by air or underwater cross-shelf transport from 

land. 

The vast stretches of sands throughout the sanctuary support a highly diverse and abundant 

infaunal community, a finding which should change a frequent misconception that these 

“featureless” substrates surrounding live-bottom rocky outcrops are “biological desserts.” 

Measures of diversity (number of species and H'), for example, are about twice as high as 

those observed for the benthos in neighboring estuaries of comparable high salinity. 

The probabilistic sampling design applied in this study provides a powerful quantitative tool 

for assessing current status in conditions of the sanctuary and for using this information as a 

baseline for tracking any future changes due to natural or anthropogenic influences. At 

present, zero % of the sanctuary area shows any significant evidence of impaired benthic 

condition coupled to adverse levels of chemical contaminants in sediments. However, the 

presence of trace concentrations of pesticides, PCBs, and PAHs in both sediments and biota 

demonstrate that chemical substances originating from human activities are capable of 

reaching the offshore sanctuary environment and thus should be monitored to ensure that 

future problems do not develop. 

Results of this study provide information on current environmental conditions and future 

monitoring strategies to use in the development of revised sanctuary management plans. 

6. Acknowledgments 

This work was sponsored by the NOAA National Marine Sanctuaries (NMS) Program. Special 

recognition is extended to Reed Bohne (NOAA/GRNMS Office), Charlie Alexander 

(NOAA/NMS Headquarters), Nathalie Valette-Silver (NOAA/NCCOS Headquarters), and Jon 

Hare (NOAA/NCCOS/CCFHR) for program coordination; to Barry Vittor & Associates 

(Mobile, AL) for analysis of macroinfaunal samples, TOC, and particle-size; to Peter Jenkins, 
13

Aaron Dias, Eric Strozier, Scott Sivertsen, and Brian Shaddrix (NOAA/NCCOS/CCEHBR) for 

analysis of contaminants in sediments and tissues; and to Cathy Sakas, Greg McFall, and Ralph 

Rogers (NOAA/GRNMS Office), as well as the crew of the NOAA Ship FERREL, for assistance 

with sample collections. 

7. References 

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assessment, April 2000. Final Report to NOAA under contract No. 50-DGNC-0-90024, 

NOAA NOS, Charleston, SC. 

Chapman, P.M. 1990. The sediment quality triad approach to determining pollution-induced 

degradation. Science Total Environment, 97(98): 815-825. 

Diaz, R.J., & R. Rosenberg. 1995. Marine benthic hypoxia: A review of its ecological effects and 

the behavioral responses of benthic macrofauna. Oceanography & Marine Biology: an 

Annual Review, 1995, 33: 245-303. 

FDA. 1984. Polychlorinated biphenyls (PCBs) in fish and shellfish; Reduction of Tolerances; 

Final Decision. Federal Register, Vol. 49, No. 100. 21 CFR Part 109. 

FDA. 1993a. Guidance document for arsenic in shellfish. Center for Food Safety and Applied 

Nutrition. U.S. Food and Drug Administration, Washington, DC. 

FDA. 1993b. Guidance document for cadmium in shell-fish. Center for Food Safety and Applied 

Nutrition. U.S. Food and Drug Administration, Washington, DC. 

FDA. 1993c. Guidance document for chromium in shell-fish. Center for Food Safety and 

Applied Nutrition. U.S. Food and Drug Administration, Washington, DC. 

FDA. 1993d. Guidance document for lead in shellfish. Center for Food Safety and Applied 

Nutrition. U.S. Food and Drug Administration, Washington, DC. 

FDA. 1993e. Guidance document for nickel in shellfish. Center for Food Safety and Applied 

Nutrition. U.S. Food and Drug Administration. Washington, DC. 

FDA. 1994. Action levels for poisonous or deleterious substances in human food and animal 

feed. Department of Health and Human Services, Public Health Service, Food and Drug 

Administration. Washington, DC. 

Long, E.R., D.D. MacDonald, S.L. Smith, & F.D. Calder. 1995. Incidence of adverse biological 

effects within ranges of chemical concentrations in marine and estuarine sediments. 

Environmental Management, 19: 81–97. 
14

Long, E.R. & L.G. Morgan. 1990. The potential for biological effects of sediment-sorbed 

contaminants tested in the National Status and Trends Program. NOAA Tech. Memo. 

NOS OMA 52, NOAA, Silver Spring, MD. 

MacDonald, D.D, R.S. Carr, F.D. Calder, E.R. Long, & C.G. Ingersoll. 1996. Development and 

evaluation of sediment quality guidelines for FL coastal waters. Ecotoxicology, 5: 253-

278. 

Marine Resources Research Institute (MRRI). 1982. South Atlantic OCS Area Living Marine 

Resources Study, Year II. Vols. I-III. Final Report submitted by MRRI (S.C. Wildlife 

and Marine Resources Department) under Contract AA551-CT1-18 to Minerals 

Management Service, Washington, D.C. 

Sedberry, G.R. 1985. Food and feeding of the tomtate, Haemulon aurolineatum (Pisces, 

Haemulidae), the South Atlantic Bight. Fishery Bulletin, 83(3): 461-466. 

Van Dolah, R.F., P.H. Wendt, D.A. Goldman, A.B. Wrona, R.A. Pardieck, & M.V. Levisen. 

1997. An Assessment of Benthic Infaunal Assemblages and Sediments in the Vicinity of 

the Charleston Ocean Dredged Material Disposal Area. Final Report submitted by 

Marine Resources Research Institute (S.C. Department of Natural Resources) to U.S. 

Army Corps of Engineers Charleston District. 59 p and 3 appendices. 

Windom, H.L., S.J. Schropp, F.D. Calder, J.D. Ryan, R.G. Smith Jr., L.C. Burney, F.G. Lewis, 

and C.H. Rawlinson. Natural trace metal concentrations in estuarine and coastal marine 

sediments of the southeastern United States. Environmental Science and Technology, 23: 

314-320. 
Appendix A. Summary of station location, water quality and sediment data for stations sampled within GRNMS 

Modification of table from Barry A. Vittor & Associates, Inc. (2001). 

Bottom Water 

Station Latitude Longitude Depth (m) Temp ( ̊C) Salinity (ppt) D.O. (mg/L) pH TOC (mg/g) % Gravel % Sand 

1 31.4199 ̊ 80.9099 ̊ 17.5 17.8 33.6 8.4 7.9 1.1 0.00 99.87 2 31.4160 ̊ 80.8876 ̊ 19.3 17.9 33.7 8.2 7.9 1.1 3.36 96.14 3 31.4192 ̊ 80.8670 ̊ 19.4 17.9 33.8 8.3 7.9 1.5 0.00 99.45 4 31.4107 ̊ 80.8586 ̊ 20.8 17.9 33.8 8.2 7.9 1.2 0.00 99.74 5 31.4154 ̊ 80.8381 ̊ 21.1 17.6 34.1 8.2 7.9 0.8 0.00 99.82 6 31.4061 ̊ 80.9123 ̊ 18.0 17.9 34.0 7.9 7.9 1.3 0.00 99.79 7 31.3968 ̊ 80.8965 ̊ 16.0 17.9 34.0 7.9 7.9 1.3 0.00 99.53 8 31.3948 ̊ 80.8686 ̊ 14.5 18.2 33.9 8.1 7.6 4.9 9.41 90.04 9 31.3949 ̊ 80.8619 ̊ 19.7 18.2 33.9 8.2 7.9 1.2 0.00 99.56 

10 31.4058 ̊ 80.8328 ̊ 19.0 17.7 34.1 8.2 7.9 1.4 4.39 94.73 11 31.3912 ̊ 80.9058 ̊ 16.7 17.9 34.0 7.9 8.0 1.9 0.00 99.69 12 31.3898 ̊ 80.8962 ̊ 17.0 17.9 34.1 7.9 8.0 4.2 0.00 99.37 13 31.3869 ̊ 80.8748 ̊ 18.7 17.9 34.2 7.9 8.0 1.8 0.00 99.46 14 31.3829 ̊ 80.8595 ̊ 19.3 18.0 33.7 7.7 8.0 1.4 3.57 96.19 15 31.3834 ̊ 80.8402 ̊ 18.1 18.0 33.9 7.7 8.0 1.5 0.00 99.76 16 31.3768 ̊ 80.9184 ̊ 15.2 18.0 34.1 8.0 8.0 1.3 3.55 96.18 17 31.3671 ̊ 80.8978 ̊ 19.6 17.9 34.3 7.9 8.0 19.7 15.53 83.79 

18 31.3830 ̊ 80.8784 ̊ 17.0 17.9 34.3 7.9 8.0 2.7 6.25 93.38 19 31.3628 ̊ 80.8537 ̊ 19.0 18.0 33.9 7.6 8.1 1.6 0.00 99.29 20 31.3735 ̊ 80.8413 ̊ 19.2 18.0 33.9 7.7 8.0 1.3 2.23 97.51 
Appendix B. Summary of contaminant concentrations and sediment quality guideline (SQG) exceedances at GR

2000 (n = 20 sites). Concentrations of analytes below method detection limits are reported as < MDL; in such cawas used for data computations (e.g., averaging across all stations). 

Range SQG # 

Analyte Average Min Max ER-L/TELa ER-M/PELb ER-L/T

Metals (μg/g dry wt., unless otherwise indicated) Aluminum (%) 0.04 0.01 0.07 -- -- -- Arsenic 0.98 0.12 3.15 8.2 70 0 Cadmium 0.03 < MDL 0.23 1.2 9.6 0 Chromium 0.02 < MDL 0.26 81 370 0 Copper 5.30 < MDL 103.00 34 270 1 Iron (%) 0.16 0.04 0.39 -- -- -- Lead 0.52 0.01 2.19 46.7 218 0 Manganese 17.15 7.36 35.60 -- -- -- Mercury < MDL < MDL < MDL 0.15 0.71 0 Nickel 2.38 0.91 5.00 20.9 51.6 0 Selenium 0.03 < MDL 0.21 -- -- -- Silver 0.05 < MDL 0.93 1.0 3.7 0 Tin < MDL < MDL < MDL -- -- -- Zinc 9.43 < MDL 40.80 150 410 0 PAHs (ng/g dry wt.) Acenaphthene < MDL < MDL < MDL 16 500 0 Acenaphthylene < MDL < MDL < MDL 44 640 0 Anthracene < MDL < MDL < MDL 85.3 1100 0 Benzo(a)anthracene < MDL < MDL < MDL 261 1600 0 Benzo(a)pyrene < MDL < MDL < MDL 430 1600 0 
Range SQG # 

Analyte Average Min Max ER-L/TELa ER-M/PELb ER-L/T

Benzo(b)fluoranthene < MDL < MDL < MDL -- -- -- Benzo(e)pyrene < MDL < MDL < MDL -- -- -- Benzo(g,h,i)perylene < MDL < MDL < MDL -- -- -- Benzo(j+k)fluoranthene < MDL < MDL < MDL -- -- -- Biphenyl < MDL < MDL < MDL -- -- -- Chrysene+Triphenylene < MDL < MDL < MDL -- -- -- Dibenz(a,h+a,c)anthracene < MDL < MDL < MDL 63.4 260 0 Dibenzothiophene < MDL < MDL < MDL -- -- -- 2,6 Dimethylnaphthalene < MDL < MDL < MDL -- -- -- Fluoranthene < MDL < MDL < MDL 600 5100 0 Fluorene < MDL < MDL < MDL 19 540 0 Indeno(1,2,3-cd)pyrene < MDL < MDL < MDL -- -- -- 1-Methylnaphthalene 2.08 < MDL 9.12 -- -- -- 2-Methylnaphthalene 4.05 < MDL 16.30 70 670 0 1-Methylphenanthrene < MDL < MDL < MDL -- -- -- Naphthalene 8.11 < MDL 32.50 160 2100 0 Perylene < MDL < MDL < MDL 240 1500 0 Phenanthrene < MDL < MDL < MDL -- -- -- Pyrene < MDL < MDL < MDL 665 2600 0 1,6,7 Trimethylnaphthalene < MDL < MDL < MDL -- -- -- Total PAHsc 14.24 < MDL 57.82 4022 44792 0 PCBs (ng/g dry wt.) Total PCBs 1.12 0.12 1.77 22.7 180 0 Pesticides (ng/g dry wt.) Aldrin < MDL < MDL < MDL -- -- -- 

Appendix B (Continued). 
Range SQG # 

Analyte Average Min Max ER-L/TELa ER-M/PELb ER-L/T

Alpha-chlordane < MDL < MDL < MDL -- -- -- Chlorpyrifos 0.02 < MDL 0.13 -- -- -- Dieldrin < MDL < MDL < MDL 15.2d 0.715e 0 Endosulfan ether < MDL < MDL < MDL -- -- -- Endosulfan I < MDL < MDL < MDL -- -- -- Endosulfan II < MDL < MDL < MDL -- -- -- Endosulfan lactone < MDL < MDL < MDL -- -- -- Endosulfan sulfate < MDL < MDL < MDL -- -- -- Heptachlor < MDL < MDL < MDL -- -- -- Heptachlor epoxide < MDL < MDL < MDL -- -- -- Hexachlorobenzene < MDL < MDL < MDL -- -- -- Lindanef < MDL < MDL < MDL 0.32d 0.99e 0 Mirex < MDL < MDL < MDL -- -- -- Trans-nonachlor < MDL < MDL < MDL -- -- -- DDDg < MDL < MDL < MDL -- -- -- DDEg < MDL < MDL < MDL -- -- -- DDTg 0.00 < MDL 0.09 -- -- -- Total DDTh 0.00 < MDL 0.09 1.58d 46.1e 0 a SQG value is the ERL value from Long et al. (1995), unless noted otherwise. b SQG value is the ERM value from Long et al. (1995), unless noted otherwise. c Without Perylene. d TEL value from MacDonald et al. (1996). e PEL value from MacDonald et al. (1996). f Gamma BHC. g DDD = 2 ́4 ́-DDD + 4 ́4 ́-DDD; DDE = 2 ́4 ́-DDE + 4 ́4 ́-DDE; DDT = 2 ́4 ́-DDT + 4 ́4 ́-DDT. h Total DDTs = 2 ́4 ́-DDD + 4 ́4 ́-DDD + 2 ́4 ́-DDE + 4 ́4 ́-DDE + 2 ́4 ́-DDT + 4 ́4 ́-DDT. 
Appendix C. Summary of contaminant concentration ranges observed in edible tissues of black sea bass and arc 

sites in April 2000. All concentrations are reported on a dry-weight basis. FDA guideline values are included (whave been converted to dry weight by multiplying published wet-weight values by a factor of 5. Concentrations o

method detection limits are reported as < MDL; in such cases, a value of zero was used for data computations (e.all stations). 

Black Sea Bass (n=10) Arc Shell (n=9) Analyte Average Range Average Range 

G

Metals (μg/g dry wt.) 

Aluminum 48.72 40.40 61.80 89.86 59.30 182.00 Arsenic 58.52 6.76 89.30 63.57 < MDL 93.00 

Cadmium < MDL < MDL < MDL 4.01 < MDL 7.79 

Chromium < MDL < MDL < MDL < MDL < MDL < MDL Copper 0.41 0.19 1.17 5.96 < MDL 8.02 Iron 1.90 < MDL 16.90 147.89 60.70 294.00 Lead 0.30 < MDL 2.64 0.40 < MDL 2.92 

Manganese 0.13 < MDL 0.55 17.11 < MDL 26.70 Mercury 0.23 0.11 0.59 0.05 < MDL 0.12 

Nickel 2.20 < MDL 21.70 1.37 < MDL 3.80 

Selenium 2.83 2.43 3.35 6.79 5.13 10.30 Silver 0.05 < MDL 0.18 3.24 1.60 4.66 Tin < MDL < MDL < MDL < MDL < MDL < MDL Zinc 24.33 < MDL 47.30 114.11 < MDL 211.00 

PAHs (ng/g dry wt.)Acenaphthene < MDL < MDL < MDL < MDL < MDL < MDL Acenaphthylene < MDL < MDL < MDL < MDL < MDL < MDL Anthracene < MDL < MDL < MDL < MDL < MDL < MDL Benzo(a)anthracene < MDL < MDL < MDL < MDL < MDL < MDL Benzo(a)pyrene < MDL < MDL < MDL < MDL < MDL < MDL Benzo(e)pyrene < MDL < MDL < MDL < MDL < MDL < MDL 
Black Sea Bass (n=10) Arc Shell (n=9) Analyte Average Range Average Range 

G

Benzo(b)fluoranthene < MDL < MDL < MDL < MDL < MDL < MDL Benzo(g,h,i)perylene < MDL < MDL < MDL < MDL < MDL < MDL Benzo(j+k)fluoranthene < MDL < MDL < MDL < MDL < MDL < MDL Biphenyl < MDL < MDL < MDL < MDL < MDL < MDL Chrysene+Triphenylene < MDL < MDL < MDL < MDL < MDL < MDL Dibenz(a,h+a,c)anthracene < MDL < MDL < MDL < MDL < MDL < MDL Dibe

nzot

hiop

hene < MDL < MDL < MDL 0.15 < MDL 1.32 

2,6 Dimethylnaphthalene < MDL < MDL < MDL < MDL < MDL < MDL Fluoranthene < MDL < MDL < MDL < MDL < MDL < MDL Fluorene < MDL < MDL < MDL < MDL < MDL < MDL Indeno(1,2,3-cd)pyrene < MDL < MDL < MDL < MDL < MDL < MDL 1-Methylnaphthalene < MDL < MDL < MDL < MDL < MDL < MDL 2-Methylnaphthalene 2.62 < MDL 26.20 16.07 < MDL 48.50 1-Methylphenanthrene < MDL < MDL < MDL < MDL < MDL < MDL Naphthalene < MDL < MDL < MDL 6.87 < MDL 61.80 Perylene < MDL < MDL < MDL < MDL < MDL < MDL Phenanthrene < MDL < MDL < MDL < MDL < MDL < MDL Pyrene < MDL < MDL < MDL < MDL < MDL < MDL 1,6,7 Trimethylnaphthalene < MDL < MDL < MDL < MDL < MDL < MDL Total PAHs w/o Perylene 2.62 < MDL 26.20 22.93 < MDL 110.30 PCBs (ng/g dry wt.) Total PCBs 10.52 5.23 19.90 2.11 1.25 2.68 Pesticides (ng/g dry wt.)Aldrin < MDL < MDL < MDL < MDL < MDL < MDL Alpha-chlordane < MDL < MDL < MDL < MDL < MDL < MDL Chlorpyrifos 0.10 < MDL 0.60 0.14 < MDL 0.84 

Appendix C. (continued) 
Black Sea Bass (n=10) Arc Shell (n=9) Analyte Average Range Average Range 

G

DDDd < MDL < MDL < MDL < MDL < MDL < MDL DDEd 0.73 0.35 1.93 0.26 < MDL 0.41 DDTd 0.09 < MDL 0.26 < MDL < MDL < MDL Total DDTse 0.82 0.35 2.19 0.26 < MDL 0.41 Dieldrin 0.10 < MDL 0.41 0.04 < MDL 0.35 Endosulfan ether 0.02 < MDL 0.24 < MDL < MDL < MDL Endosulfan I < MDL < MDL < MDL < MDL < MDL < MDL Endosulfan II < MDL < MDL < MDL < MDL < MDL < MDL Endosulfan lactone < MDL < MDL < MDL < MDL < MDL < MDL Endosulfan sulfate < MDL < MDL < MDL < MDL < MDL < MDL Heptachlor 0.03 < MDL 0.10 < MDL < MDL < MDL Heptachlor epoxide 0.27 < MDL 2.69 2.87 2.18 3.59 

Hexachlorobenzene 0.07 < MDL 0.13 0.01 < MDL 0.06 Lindane 0.79 0.15 1.34 0.94 0.73 1.13 Mirex 0.22 < MDL 0.86 < MDL < MDL < MDL 

Trans-nonachlor 0.17 < MDL 0.39 < MDL < MDL < MDL 

Lipids (% dry wt.) 1.53 0.85 3.00 6.20 4.73 7.18 a FDA Level of Concern for contaminant in shellfish. Value is lowest of multiple values reported by FDA for humans of various ages c

crustaceans or mollusks at the 90th percentile consumption rate. Values (converted from wet weight to dry weight) are from: FDA 1993

Cd, FDA 1993c for Cr, FDA 1993d for Pb, FDA 1993e for Ni. 

b FDA Action Level for poisonous or deleterious substances in human food and animal feed (level for edible portion of fish is given). Fc FDA Tolerance for unavoidable residues of PCBs in fish and shellfish. FDA 1984. d DDD = 2 ́4 ́-DDD + 4 ́4 ́-DDD; DDE = 2 ́4 ́-DDE + 4 ́4 ́-DDE; DDT = 2 ́4 ́-DDT + 4 ́4 ́-DDT. Classification used by FDA 1994. e Total DDTs = 2 ́4 ́-DDD + 4 ́4 ́-DDD + 2 ́4 ́-DDE + 4 ́4 ́-DDE + 2 ́4 ́-DDT + 4 ́4 ́-DDT. 

Appendix C. (continued)