PATUXENT RIVER OIL SPILL: 

ASSESSMENT OF IMPACTS 

ON BENTHOS 

Final Report

Prepared for 

Swanson Creek Natural Resource Damage 

Assessment Trustee Council 

Under Contract With 

Entrix 

10 Corporate Circle, Suite 100 

New Castle, Delaware 

Prepared by 

Roberto J. Llansó 

Jon Vølstad 

Versar, Inc. 

9200 Rumsey Road 

Columbia, Maryland 21045 

November 1, 2001 
Foreword 

ii 

FOREWORD 

 This document, Patuxent River Oil Spill: Assessment of Impacts on Benthos, was 

prepared by Versar, Inc., at the request of the Swanson Creek NRDA Trustee Council under 

contract No. 729901, Task Order 0100, between Versar, Inc., and Entrix. The report assesses 

impacts on the benthic communities of Swanson Creek and the Patuxent River at Chalk Point 

as a result of the oil spill of 7 April 2000. 
Abstract 

iii 

ABSTRACT 

On 7 April 2000, approximately 126,000 gallons of oil were spilled into the Patuxent 

River in the vicinity of Chalk Point. An assessment of the potential impacts from the oil spill on 

benthic communities was conducted in conjunction with scheduled Chesapeake Bay Program 

monitoring activities. Macroinfauna and sediment characteristics were analyzed in Swanson 

Creek in the immediate vicinity of the spill and compared to the mainstem of the Patuxent River 

and to Hunting Creek, a presumably undisturbed control creek. Significant differences in 

benthic community parameters between Swanson Creek and both Hunting Creek and the 

Patuxent mainstem were found 3-6 months after the spill. These differences were mostly 

restricted to the upper portion of Swanson Creek, and indicated changes in benthic community 

structure (e.g., reduced diversity, increased abundance of pollution-indicative species) that were 

similar to those commonly reported for anthropogenic impacts. Benthic community structure as 

measured by the Chesapeake Bay index of biotic integrity was also classified predominately as 

degraded in this region. The impact, however, if attributable to the oil spill, appeared localized 

and of relatively low magnitude. 
Table of Contents 

iv 

TABLE OF CONTENTS

Page 

FOREWORD.................................................................................................................................ii 

ABSTRACT .................................................................................................................................iii 

1.0 INTRODUCTION............................................................................................................1-1

2.0 METHODS .....................................................................................................................2-1 

 2.1 APPROACH .......................................................................................................2-1 

 2.1.1 River Component.................................................................................2-1 

2.1.2 Creek Component................................................................................2-3 

 2.2 FIELD AND LABORATORY PROCEDURES.....................................................2-3 

 2.3 DATA ANALYSIS ...............................................................................................2-4 

3.0 RESULTS ......................................................................................................................3-1 

3.1 RIVER COMPONENT ........................................................................................3-1 

3.2 CREEK COMPONENT.......................................................................................3-2 

3.3 BENTHIC INDEX OF BIOTIC INTEGRITY.........................................................3-3 

4.0 DISCUSSION.................................................................................................................4-1 

5.0 REFERENCES...............................................................................................................5-1 

APPENDICES 

A BOTTOM ENVIRONMENT AND BENTHOS, SPRING..................................... A-1 

 B BOTTOM ENVIRONMENT AND BENTHOS, SUMMER................................... B-1 

F:\DATA\WPSHARED\DEPT.74\Entrix\12777-R.doc
List of Figures 

v 

LIST OF FIGURES 

Figure Page 

1 Oil spill location (source: Maryland DNR web site) ........................................................1-3 

2 Patuxent River. Sites sampled in June 2000 ................................................................2-5 

3 Patuxent River. Sites sampled in September 2000.......................................................2-6 

4 June mainstem comparisons .........................................................................................3-4 

5 September mainstem comparisons................................................................................3-5 

6 Station 074, May 1991-2000 ..........................................................................................3-6 

7 Station 074, August-September 1990-2000...................................................................3-7 

8 Mean abundance at the impact station in Chalk Point and at a control 

station in the Chester River, 1990-2000.........................................................................3-8 

9 June creek comparisons ................................................................................................3-9 

10 June creek comparisons (continued) ...........................................................................3-10 

11 September creek comparisons ....................................................................................3-11 

12 Percent abundance composition at June creek and river sites....................................3-12 

13 Percent abundance composition at September creek and river sites ..........................3-13 

14 Benthic community condition at creek and river sites in September 2000...................3-13 

15 Benthic community condition at LTB Patuxent River sites in September 2000............3-14 
Introduction 

1-1 

1.0 INTRODUCTION 

 On 7 April 2000, approximately 126,000 gallons of oil were spilled into the Patuxent 

River in the vicinity of Chalk Point. The spill resulted from a rupture of a pipeline owned by the 

Potomac Electric Power Company (PEPCO). Versar was directed by the natural resources 

trustees to assess the impacts (if any) on the benthic communities of subtidal soft-bottom 

habitats near Chalk Point. Versar’s study is intended to provide background information to aid 

in the natural resource damage assessment process. 

 The spill occurred in sensitive marsh areas of Swanson Creek adjacent to the PEPCO 

Chalk Point generating station (Figure 1). Although booms deployed immediately after the spill 

contained much of the oil within Swanson Creek, an undetermined amount of oil leaked into the 

Patuxent River during a storm on the night of April 8. Cleanup operations recovered over 

45,000 gallons of oil. In addition to Swanson Creek, potentially affected areas included the 

main Patuxent River downstream of Chalk Point and shallow embayments and creeks south of 

the town of Benedict. Visual assessments conducted within a month of the spill revealed no oil 

in samples from creek or river bottom sediments (Swanson Creek Marsh Joint Information 

Center Press Release of 1 May 2000). Some oil, however, was observed in association with 

the intertidal zones of shorelines. A reconnaissance field visit made to the spill site by Versar 

found a substantial amount of oil within the marsh areas (Harriott 2000). This last study, 

conducted on 17 and 18 April 2000, mapped wetland vegetation types along Swanson Creek 

(1.6 Km upstream and 0.8 Km downstream of the spill location) and provided observations of 

physical impacts on the marsh. 

 The present study was conducted in conjunction with the Maryland Chesapeake Bay 

Long-Term Benthic Monitoring Program (LTB) with the objective of determining whether the 

benthos were adversely affected by the oil spill. LTB has monitored the health of benthic 

communities in Chesapeake Bay since 1984. As part of its bay-wide sampling design, LTB 

collects annual samples at fixed and random locations throughout the Patuxent River. Fixed 

locations are used to evaluate trends in benthic community condition over time. Random 

locations are used to estimate the percentage of river bottom that meets the Chesapeake Bay 

Benthic Community Restoration Goals. The Restoration Goals are benchmarks that describe 

the characteristics of benthic assemblages expected in non-degraded habitats of Chesapeake 

Bay. LTB has accumulated an extensive data base of benthic and water quality data in the 

region. This study was integrated with on-going LTB efforts so that LTB data, as well as 

common locations and platforms for the collection of samples, could be used. 

 Benthic organisms are generally included in monitoring programs and environmental 

impact assessments because they are reliable and sensitive indicators of habitat quality in 

aquatic environments. Most benthic organisms have limited mobility and cannot avoid changes 

in environmental conditions (Gray 1979). Benthos live in bottom sediments where exposure to 

contaminants and low dissolved oxygen is generally high, although relative exposure to 

contaminants in sediments depends on a variety of factors. Benthic communities include 

diverse taxa representing a variety of physiological tolerances to environmental conditions. 

They respond, therefore, to changes in environmental conditions, both natural and 

anthropogenic, in a variety of ways, and are sensitive indicators and integrators of 
Introduction 

1-2 

environmental change (Pearson and Rosenberg 1978, Warwick 1986, Dauer 1993, Wilson and 

Jeffrey 1994). 
Introduction 

1-3 

Figure 1. Oil spill location (source: Maryland DNR web site). 
Methods 

2-1 

2.0 METHODS 

2.1 APPROACH 

 The study consisted of river and creek subtidal benthic assessments. The river 

component consisted of revisiting sites in the mainstem of the Patuxent River that were 

previously sampled as part of LTB, plus the addition of new sites. The creek component 

allocated random samples to Swanson Creek in the immediate vicinity of the spill, and to a 

presumably undisturbed nearby creek (Hunting Creek). Figures 2 and 3 show the sampling 

locations. Samples were also collected in Indian Creek and Trent Hall Creek, but these 

samples were not examined in this study. Sampling was conducted on 29-30 June 2000 upon 

contract award and in conjunction with the next scheduled LTB sampling event on 27-29 

September 2000. 

2.1.1 River Component 

The sampling approach was based on the Before-After-Control-Impact design (BACI) 

(Stewart-Oaten et al. 1986, Underwood 1991) with modifications to take advantage of the large 

data set collected by the LTB program. The LTB data included samples from several years (up 

to five years for random locations and up to 17 years for a fixed location at Chalk Point) before 

the perturbation at both the impact site in the Patuxent River and control sites in nearby rivers 

(for example, the Potomac and Chester Rivers). The BACI design allows for natural differences 

between Control and Impact locations, as well as for changes between the Before and After 

period that influence the sites in a similar way. We tested whether the mean Impact-Control 

difference changed before and after the oil spill. We used data collected by LTB in May 1991-

2000 and August-September 1990-2000 at two fixed locations (impact Station 074 and control 

Station 068), and data collected in August-September 1995-2000 at several random locations in 

the main Patuxent near Chalk Point. These data were supplemented by additional collections 

from random sites sampled specifically for this study (Table 1). 

For the oil spill assessment, the main Patuxent River was sampled at 12 sites in June 

2000 and at 10 sites in September 2000. Sites were located in the Chalk Point region between 

the Highway 231 bridge at Benedict and Holland Cliff upstream (Figures 2 and 3). Of the 12 

June sites, six were sampled in 1990-1993 as part of LTB (Table 1). The other six were newly 

established in order to increase coverage in the area immediately adjacent to Chalk Point. The 

random sites used in June 1990-1993 did not adequately cover this area. The 10 September 

sites were all previously sampled in 1998 or 1999 as part of LTB. 
Methods 

2-2 

Table 1. Data available for the Patuxent River oil spill benthic assessment.

Sampling Date Location Source Number of Samples

River Component 

June 1990-1993 Main Patuxent LTB 3 per year

June 2000 Main Patuxent This study 12

September 1995 Main Patuxent LTB 3

September 1997 Main Patuxent LTB 1

August 1998 Main Patuxent LTB 3

August 1999 Main Patuxent LTB 7

September 2000 Main Patuxent LTB 4

September 2000 Main Patuxent This study 10

May 1991-1994 Station 074 LTB 1 per year

May 1996-2000 Station 074 LTB 3 per year

Aug.-Sept. 1990-1994 Station 074 LTB 1 per year

Aug.-Sept. 1995-2000 Station 074 LTB 3 per year

May 1991-1992 Station 068 LTB 2 per year

May 1993-1994 Station 068 LTB 1 per year

May 1996-2000 Station 068 LTB 3 per year

Aug.-Sept. 1990-1992 Station 068 LTB 1 per year

September 1993 Station 068 LTB 2

August 1994 Station 068 LTB 1

Aug-Sept. 1995-2000 Station 068 LTB 3 per year

Creek Component 

June 2000 Upper Swanson This study 3

June 2000 Lower Swanson This study 7

June 2000 Hunting This study 10

September 2000 Upper Swanson This study 10

September 2000 Lower Swanson This study 10

September 2000 Hunting This study 10
Methods 

2-3 

2.1.2 Creek Component 

No previous benthic data were available from Swanson Creek. Therefore, Hunting 

Creek was selected for comparison. Ten sites were randomly allocated to each creek in June 

2000 (Table 1, Figure 2). In September, sampling effort in Swanson Creek was increased to 20 

sites allocated proportionally among two strata (Table 1, Figure 3). In addition, 10 sites were 

sampled in each of Hunting Creek, Indian Creek, and Trent Hall Creek. Indian Creek and Trent 

Hall Creek were sampled as requested by the trustees; however, the samples were archived 

pending potential future analysis. 

In order to provide estimates of seasonal variability, half of the sites sampled in June 

were revisited in September (Figure 3). Sites to be revisited were selected at random. In upper 

Swanson Creek, three sites had been sampled in June, but one was associated with marsh 

vegetation and was excluded from consideration. Therefore, only two sites were revisited in 

upper Swanson Creek. Additional September sites in all creeks were aimed at providing 

increased spatial coverage. 

2.2 FIELD AND LABORATORY PROCEDURES 

 Sediment samples were collected using a Young grab, which samples an area of 440 

cm2

 to a depth of 10 cm. One sample per site was taken. With the exception of the 1990-1993 

LTB samples, collected with a Wildco box corer, the same gear and methods were used for all 

collections. Grab samples were sieved through a 0.5-mm mesh screen, and the organisms 

retained on the screen were preserved in a 10% formalin solution and stained. In the 

laboratory, organisms were counted, identified, and their biomass (ash-free dry weight) 

measured following LTB protocols. Ash-free dry weight was determined for each species by 

drying the organisms to a constant weight at 60 o

C followed by ashing in a muffle furnace at 500 o

C for four hours. Because most species of oligochaetes need to be slide mounted for 

identification, species-specific biomass for oligochaetes could not be provided except for 

Tubificoides spp., which do not need slide mounting for identification. All sorting and 

identification were conducted at Versar. 

 Surface and bottom water temperature, conductivity, salinity, and dissolved oxygen 

concentration were measured at most sites using a Hydrolab multiprobe. The unit became 

inoperable at a few sites, so for these sites water quality parameter values are not available. 

Surface sediment for silt-clay and organic carbon content analysis was collected from an 

additional grab sample at each site. Surface sediment (top 2 cm) samples were also taken at 

each site for analysis of PAH concentration. PAH samples were frozen and archived as 

directed by the trustees. 

Sediment grain size analysis followed procedures described in Folk (1980). Sand was 

separated from silt-clay by wet sieving and the percent silt-clay fraction (particles smaller than 

63 microns) was determined by weighing. Percent organic carbon (TOC) was determined by 

combustion at 550 o

C in a carbon analyzer (Exeter Analytical Inc. CE440 Elemental Analyzer) 

for four hours. Analysis of TOC samples was provided by the Chesapeake Biological 

Laboratory. 
Methods 

2-4 

2.3 DATA ANALYSIS 

 Data from the river component was analyzed using the BACI design outline above. LTB 

stations 074 and 068 were compared. Station 068 is located in the upper Chester River and 

has habitat characteristics similar to station 074. Benthic community condition at station 068 

meets the benthic community restoration goals and therefore can be used as a reference. The 

BACI design could not be applied to LTB random data collected 1995-2000 in the vicinity of 

Chalk Point because there were no comparable post-spill data outside the Patuxent River 

available at this time. However, data were analyzed for differences in benthic community 

parameters across years using a generalized linear model (see below). 

 In addition to the above analysis, September data were interpreted in the context of 

measures of benthic community health using the Chesapeake Bay benthic index of biotic 

integrity (B-IBI, Weisberg et al. 1997, updated in Alden et al. 2002). The B-IBI takes into 

account the natural range of variability within reference areas in Chesapeake Bay. The B-IBI is 

based on a number of summer time benthic invertebrate attributes such as total abundance and 

biomass, diversity, abundance of pollution indicative species, and biomass of pollution sensitive 

species (Weisberg et al. 1997, see Appendix B of this report for details). The index is calculated 

by scoring each attribute as either 5, 3, or 1 depending on whether the value of the attribute 

approximates, deviates slightly from, or deviates strongly from values at the best reference sites 

in similar habitats. These scores are then averaged across attributes to obtain an index value. 

Index values of 3 or more are considered to meet the restoration goals. 

 For the creek component, we assessed the magnitude of the impact by comparing sites 

near to and distant from the spill source. Data were analyzed with ANOVA (alpha level = 0.05) 

using the General Linear Model procedure in SAS for unbalance designs (SAS Institute, Inc., v. 

8). Abundance and biomass data were standardized to values per square meter and log 

transformed to lessen the sensitivity of the method to large abundances. The log transformation 

stabilizes the variance and reduces or eliminates dependence between the variance and the 

mean. 
Methods 

2-5 

Figure 2. Patuxent River. Sites sampled in June 2000. 
Methods 

2-6 

Figure 3. Patuxent River. Sites sampled in September 2000. 
Results 

3-1 

3.0 RESULTS 

For each comparison (e.g., Patuxent mainstem vs. LTB), Shannon diversity (H’, with 

log2), number of species, abundance, and biomass are presented below. Whenever the number 

of samples for a comparison is greater than 1 (see Table 1), we have plotted the mean plus or 

minus one standard error. All statistical analyses are based on means. Shannon diversity and 

number of species should be interpreted with caution for those comparisons where the number 

of samples varies among locations, as a higher number of species would be expected with 

increased replication. To be consistent with LTB protocols, epifaunal organisms were excluded 

from calculations except where indicated. All organisms collected during this study are listed in 

the appendices. The appendices summarize water quality measurements, sediment 

parameters, and benthic community data for all sites. 

3.1 RIVER COMPONENT 

 Shannon diversity and number of species from samples collected in the Patuxent 

mainstem in June 2000 did not differ significantly (p=0.064 and 0.861, respectively) from 1990-

1993 collections, either individually (LTB 93, LTB 92, etc., Figure 4) or as a group (LTB 90-93). 

Total abundance and biomass, however, were significantly lower in June 2000 than in June 

1990-1993 (p<0.001) (Figure 4). Inclusion of epifaunal organisms did not change these results. 

The large variability in the biomass data was due to the bivalve Rangia cuneata. Collections 

with few, relatively large individuals of this species tend to skew the data. Rangia usually 

accounts for a large portion of the biomass in the upper Patuxent River. 

 Shannon diversity, number of species, abundance, and biomass from samples collected 

in the Patuxent mainstem in September 2000 did not differ significantly from 1995-1999 summer 

collections (p=0.214, 0.055, 0.169, and 0.836, respectively) or from LTB 2000 collections 

(Figure 5). The year 1997 did not count in the comparison because it did not have a variance 

estimate. As before, inclusion of epifaunal organisms did not change these results. The 

exclusion of Rangia cuneata from the analysis resulted in relatively similar biomass patterns 

across years in the remaining community (Figure 5e). 

 Benthic community parameters for station 074 in May 2000 were within the range of 

typical values observed at this station for Shannon diversity, abundance, and biomass, and 

higher than average values for number of species (Figure 6). In September 2000, all four 

benthic community parameters were within the range of values typical of summer benthic 

collections, and within the “good range” of B-IBI thresholds (>1.7 for Shannon diversity, 500-

6000 individuals m-2 for abundance, 1-30 g m-2 for biomass) (Figure 7). Application of the BACI 

design revealed no significant differences in the relative mean abundance between the impact 

(Station 074) and the control site (Station 068) from before the spill to after the spill, indicating 

that there was no effect of the perturbation (Figure 8). Note that there was no major decline in 

the difference between impact and control sites after the spill. 

3.2 CREEK COMPONENT 
Results 

3-2 

 Comparisons between Swanson Creek, Hunting Creek, and the Patuxent mainstem 

revealed differences in benthic community parameters and species composition. Upper 

Swanson Creek most often accounted for the differences. Shannon diversity was significantly 

lower (p<0.001) in upper Swanson Creek in June 2000 than in lower Swanson Creek, Hunting 

Creek, or the Patuxent mainstem (Figure 9a). Number of species and abundance were 

significantly higher (p<0.001) in upper Swanson Creek (Figures 9b and 9c), but biomass did not 

differ significantly among locations (p=0.146), most likely as a result of the large variability in 

biomass observed in the Patuxent mainstem (Figure 9d). The polychaete Streblospio benedicti

and, to a lesser extent, the oligochaete Tubificoides spp. accounted for the large difference in 

abundance between upper Swanson Creek and the other three locations in June 2000 (Figure 

10). Streblospio was particularly abundant at station SC-02, with densities over 17,000 

individuals per square meter. Sediments from this station, adjacent to the marsh, were 

obviously oiled and contained a large proportion of organic matter (TOC = 14.7%, see Appendix 

A). When the abundance of Streblospio and Tubificoides was excluded, the abundance of the 

remaining of the community became more similar among locations (Figure 10c). Inclusion of 

epifaunal organisms in the analysis did not change these results. 

 In September 2000, Shannon diversity was significantly lower (p=0.043) in upper 

Swanson Creek than in lower Swanson Creek, Hunting Creek, or the Patuxent mainstem 

(Figure 11a). Number of species also differed significantly among locations. The Patuxent 

mainstem accounted for this difference, with significantly higher number of species (p=0.005) 

than Swanson Creek and Hunting Creek (Figure 11b). Upper Swanson Creek, however, did not 

differ significantly in number of species from lower Swanson Creek or Hunting Creek, even 

though Swanson Creek sites more often had lower species numbers than sites elsewhere 

(Figure 11b). Similar patterns were found for abundance (Figure 11c). Although some sites in 

upper Swanson Creek were impoverished, Patuxent mainstem sites exhibited the largest 

abundance (p=0.009). Biomass was significantly lower (p=0.015) in upper Swanson Creek than 

in the other three locations (Figure 11d). Inclusion of epifaunal organisms resulted in nonsignificant differences among locations for Shannon diversity (p=0.056). 

 In addition to community parameters, differences in the proportion of abundance of taxa 

classified as bivalves, crustaceans, oligochaetes, polychaetes, and others (including epifauna) 

were revealed. Overall, upper Swanson Creek had fewer bivalves and crustaceans than lower 

Swanson Creek, Hunting Creek, or the Patuxent mainstem in both June 2000 (Figure 12) and 

September 2000 (Figure 13). In June 2000, polychaetes were obviously dominant in upper 

Swanson Creek, and this pattern was still evident in September 2000, although much more 

attenuated. Notably, polychaetes also exhibited higher abundance in lower Swanson Creek 

than in Hunting Creek or the Patuxent mainstem in June 2000 (Figure 12), but not in September 

2000. 

3.3 BENTHIC INDEX OF BIOTIC INTEGRITY 

 For each of the September 2000 creek and river sites, B-IBI values and the 

corresponding benthic community condition are presented in Appendix B and Figure 14. Details 

of the B-IBI metric values and scores are provided in the appendix. In calculating the B-IBI, we 
Results 

3-3 

used low mesohaline metrics even though some sites in Swanson Creek had point-in-time 

salinity values slightly below 5.0 ppt (within the range of oligohaline habitats). We used low 

mesohaline metrics because benthic community structure in this region is typical of low 

mesohaline habitats, and long-term salinity averages are within the low mesohaline range (i.e., 

5-12 ppt). 

 Of the 10 sites in upper Swanson Creek, two met the benthic community restoration 

goals and 8 were degraded or severely degraded (see Appendix B). One of the “good” sites, 

SC-017, was only marginally so. Of the 10 sites in lower Swanson Creek, 8 met the benthic 

community restoration goals and two were degraded. In Hunting Creek, 6 sites met the goals, 3 

were degraded, and one was marginally degraded. All sites in the main Patuxent River met the 

restoration goals except the upper most site in the river (Figure 14). 

 Figure 15 shows benthic community condition at LTB sites sampled in the Patuxent 

River. Most sites in the lower Patuxent were degraded in the summer of 2000, while sites in the 

Chalk Point region further upstream met the restoration goals. 
3-4 

Figure 4. June mainstem comparisons. N/A= not available. 

Biomass (g m-2)

0.0

100.0

200.0

300.0

PATX

MAINSTEM

LTB 90-93 LTB 93 LTB 92 LTB 91 LTB 90

N/A

Abundance m-2

0

2000

4000

6000

8000

10000

12000

14000

PATX

MAINSTEM

LTB 90-93 LTB 93 LTB 92 LTB 91 LTB 90

Number of Species

4.0

6.0

8.0

10.0

12.0

14.0

16.0

PATX

MAINSTEM

LTB 90-93 LTB 93 LTB 92 LTB 91 LTB 90

Shannon Diversity

0.0

1.0

2.0

3.0

4.0

PATX

MAINSTEM

LTB 90-93 LTB 93 LTB 92 LTB 91 LTB 90

a) 

b) 

c) 

d) 
3-5 

Shannon Diversity

0.0

1.0

2.0

3.0

4.0

PATX

MAINSTEM

LTB 00 LTB 99 LTB 98 LTB 97 LTB 95

Abundance m-2

0

2000

4000

6000

8000

10000

12000

14000

PATX

MAINSTEM

LTB 00 LTB 99 LTB 98 LTB 97 LTB 95

Biomass (g m-2)

0.0

10.0

20.0

30.0

40.0

50.0

60.0

PATX

MAINSTEM

LTB 00 LTB 99 LTB 98 LTB 97 LTB 95

Number of Species

4.0

6.0

8.0

10.0

12.0

14.0

16.0

PATX

MAINSTEM

LTB 00 LTB 99 LTB 98 LTB 97 LTB 95

a) 

b) 

c) 

d) 

Figure 5. September 

mainstem comparisons. 

Dotted lines indicate thresholds used to score each metric 

of the Chesapeake Bay B-IBI. 
3-6 

Biomass (g m-2)

0.0

2.0

4.0

6.0

8.0

PATX

MAINSTEM

LTB 00 LTB 99 LTB 98 LTB 97 LTB 95

e) 

Figure 5. September mainstem comparisons (continued). Biomass in 5e excludes the 

bivalve Rangia cuneata. 
3-7 

Figure 6. Station 074, May 1991-2000. N/A= not available. 

Abundance m-2

0

5000

10000

15000

20000

25000

30000

00 99 98 97 96 95 94 93 92 91

N/A

Number of Species

4.0

6.0

8.0

10.0

12.0

14.0

16.0

00 99 98 97 96 95 94 93 92 91

N/A

a) 

b) 

c) 

d) 

Shannon Diversity

0.0

1.0

2.0

3.0

4.0

00 99 98 97 96 95 94 93 92 91

N/A

Biomass (g m-2)

0.0

50.0

100.0

150.0

200.0

00 99 98 97 96 95 94 93 92 91

N/A
3-8 

Biomass (g m-2)

0.0

10.0

20.0

30.0

40.0

50.0

60.0

00 99 98 97 96 95 94 93 92 91 90

Abundance m-2

0

2000

4000

6000

8000

10000

12000

14000

00 99 98 97 96 95 94 93 92 91 90

Number of Species

4.0

6.0

8.0

10.0

12.0

14.0

16.0

00 99 98 97 96 95 94 93 92 91 90

Shannon Diversity

0.0

1.0

2.0

3.0

4.0

00 99 98 97 96 95 94 93 92 91 90

a) 

b) 

c) 

d) 

Figure 7. Station 074, August-September 1990-2000. Dotted lines are thresholds used to 

score each metric of the Chesapeake Bay B-IBI. 
3-9 

Figure 8. Mean abundance at the impact station in Chalk Point and at a control station in the Cheste

and difference between the impact and the control station. The arrow indicates the time of the oil 

-5000

0

5000

1000015000200002500030000
3-10 

Biomass (g m-2)

0.0

2.0

4.0

6.0

8.0

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATX

MAINSTEM

Abundance m-2

0

2000

4000

6000

8000

10000

12000

14000

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATX

MAINSTEM

Number of Species

4.0

6.0

8.0

10.0

12.0

14.0

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATX

MAINSTEM

Shannon Diversity

0.0

1.0

2.0

3.0

4.0

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATX

MAINSTEM

a)

b)

c)

d)

Figure 9. June creek comparisons. 
3-11 

Remaining Abundance m-2

0

500

1000

1500

2000

2500

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATX

MAINSTEM

Tubificoides spp. Abundance m-2

0

200

400

600

800

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATX

MAINSTEM

Streblospio benedicti Abundance m-2

0

2000

4000

6000

8000

10000

12000

14000

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATX

MAINSTEM

a)

b)

c)

Figure 10. June creek comparisons (continued). Remaining abundance is total 

abundance exclusive of Streblospio benedicti and Tubificoides spp. 
3-12 

Biomass (g m-2)

0.0

2.0

4.0

6.0

8.0

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATX

MAINSTEM

 39.6

Abundance m-2

0

500

1000

1500

2000

2500

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATX

MAINSTEM

Number of Species

4.0

6.0

8.0

10.0

12.0

14.0

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATX

MAINSTEM

Shannon Diversity

0.0

1.0

2.0

3.0

4.0

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATX

MAINSTEM

a)

b)

c)

d)

Figure 11. September creek comparisons. Dotted lines indicate thresholds used to score 

each metric of the Chesapeake Bay B-IBI. 
Results 

3-13 

0

20

40

60

80

100

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATUXENT

MAINSTEM

Percent

BIVAL

CRUS

OLIGO

POLY

OTHER

June 2000

Figure 12. Percent abundance composition at June creek and river sites.

0

20

40

60

80

100

UPPER

SWANSON

LOWER

SWANSON

HUNTING PATUXENT

MAINSTEM

Percent

BIVAL

CRUS

OLIGO

POLY

OTHER

September 2000

Figure 13. Percent abundance composition at September creek and river sites. 
Results 

3-14 

Figure 14. Benthic community condition at creek and river sites in September 2000. 
Results 

3-15 

Figure 15. Benthic community condition at LTB Patuxent River sites in September 2000. 
Discussion 

4-1 

4.0 DISCUSSION 

 The effects of oil spills on benthic organisms vary as a function of the severity and 

spatial extent of the event. The effects of oil spills and chronic hydrocarbon inputs on benthic 

organisms have been previously documented (e.g., Samiullah 1985, Gray et al. 1990, 

McGuinness 1990, Agard et al. 1993, Clarke 1993). Large hydrocarbon concentrations in 

sediment are toxic to many organisms and may cause widespread mortality. However, in 

systems that experience aperiodic disturbances such as those related to high summer 

temperatures and low dissolved oxygen, sensitive species are usually eliminated (Diaz and 

Rosenberg 1995). Structural and organizational changes in the community following aperiodic 

disturbances may lead to pollution resistant communities. This may have been the case in the 

upper Patuxent River. Communities in the upper Patuxent River are likely to be resilient to 

stress. Although we are not certain of the degree to which the oil affected the bottom 

sediments, alterations to community structure were noticeable only in Swanson Creek, and 

these were apparently limited to quantitative changes in abundance, a response consistent with 

systems that experience aperiodic disturbance (Diaz 1994). 

 Benthic community parameters for sites in the mainstem of the Patuxent River in 

September 2000 were within the range of values expected for the region. In June 2000, 

abundance and biomass in the Patuxent mainstem were lower than what would be expected 

based on historical data collected in 1990-1993. However, results from the adjacent station 074 

did not indicate depressed abundance or biomass in May 2000 compared to the long-term 

average. One caveat is in order here. Estuarine benthic communities are extremely dynamic. 

Large fluctuations in abundance over time are usually common among numerically dominant 

species, especially during the spring months (April-June) when settlement and growth occur 

rapidly and densities of organisms often overshoot the carrying capacity of the environment. 

Our study is not more than a snapshot in time, limited by the constrains inherent in evaluating 

impacts from unpredictable events. With this in mind, the differences in abundance and 

biomass in the Patuxent mainstem between 2000 and 1990-1993 could be explained in several 

ways. Inter-annual variations in abundance, for example, often result from intrinsic variation in 

the population of a species, or from seasonal or annual variations in environmental factors. The 

year 2000 was extremely wet, with low dissolved oxygen occurring near Chalk Point as early as 

June (see Appendix). The overall effect of such unusual year may have been of a reduction in 

the size of the benthic populations. 

 Results from the creek component did suggest an impact in upper Swanson Creek; 

however the magnitude of the impact does not appear to have been extensive. There was no 

widespread mortality that might be associated with toxic effects. The three upper Swanson 

Creek sites sampled in June 2000 had very high densities of Streblospio benedicti, which was 

reflected in low diversity values. The average number of species at these sites, however, was 

the highest among the three locations. The average number of species was still relatively high 

in September 2000, although variability in the data indicated some sites in upper Swanson 

Creek as having low species richness. Sublethal effects may have occurred, but such effects 

usually go undetected. More evident were the changes in species composition. Upper 

Swanson Creek had proportionally fewer bivalves and crustaceans than the other three 
Results 

4-2 

locations. With oil pollution, polychaetes are enhanced while crustaceans are suppressed by 

the oil impact (Peterson et al. 1996). These results, however, should be viewed with caution. 

The natural, unaltered condition of Swanson Creek cannot be observed after the spill, and 

therefore we do not know what the benthic community would have been in the absence of the 

spill. 

 The large abundance of Streblospio benedicti in upper Swanson Creek is more difficult 

to explain, but it may have been related to organic enrichment. Quantitative changes in 

abundance with organic enrichment of the sediment are typical of opportunist species. The 

largest Streblospio densities were associated with the marsh fringe, where samples were 

obviously oiled. In this case the response may have been elicited by either the oil or the marsh 

vegetation. In general, distinguishing between the effects of organic enrichment and the effects 

of contaminant toxicity is difficult, especially when related to oil pollution. Polychaetes were 

dominant in both upper and lower Swanson Creek in June 2000. But whatever effect organic 

enrichment may have had on the community, differences in species abundance and 

composition among locations were much more attenuated in September. 

 It has been suggested that to describe the impact of oil pollution, a combination of 

community and species-based parameters should be used (Daan et al. 1992). The B-IBI 

provides such combination. The B-IBI uses measures of standing stock, diversity, species 

composition, and trophic composition. The B-IBI is applicable in summer, where the differences 

among reference and degraded sites are greatest (Alden et al. 1997). The application of the BIBI to Chalk Point data revealed that benthic community condition was worst in upper Swanson 

Creek, just around the area where cleaning and oil recovery activities were conducted after the 

spill. Whether the oil, the cleaning operation itself, or some other factor were responsible for the 

observed alterations to community structure in Swanson Creek is unknown. Ultimately, it is the 

magnitude of the impact that actually matters, especially because of the implications that these 

changes may have for economically important resources. However, given the data collected by 

this study, it is not possible to relate these changes directly to food webs. Alterations to 

abundance and species composition are most severe if sustained over the long-term or at large 

spatial scales. The information gathered during the present study suggests that the impact may 

have been largely ephemeral and of small spatial extent. However, this distinction can only be 

discerned with further sampling. Further monitoring may also help determine the time 

necessary for recovery. 

 In conclusion, this study found significant differences in benthic community parameters 

between Swanson Creek and both Hunting Creek and the Patuxent mainstem in the vicinity of 

Chalk Point 3-6 months after the spill. These differences were mostly restricted to the upper 

portion of Swanson Creek. Benthic community condition as measured by the Chesapeake Bay 

benthic index of biotic integrity was also classified predominately as degraded in this region. 

Provided that these differences are attributable to an impact from the oil spill, the impact 

appeared to be localized and of relatively low magnitude. The analysis of PAH samples may 

help determine a relationship between oil and benthic community condition. 
References 

5-1 

5.0 REFERENCES 

Agard, J.B. R., J. Gobin, and R.M. Warwick. 1993. Analysis of marine macrobenthic 

community structure in relation to pollution, natural oil seepage and seasonal 

disturbance in a tropical environment (Trinidad, West Indies). Mar. Ecol. Prog. Ser.

92:233-243. 

Alden, R.W., III, D.M. Dauer, J.A. Ranasinghe, L.C. Scott, and R.J. Llansó. 2002. Statistical 

Verification of the Chesapeake Bay Benthic Index of Biotic Integrity. Environmetrics. In 

Press. 

Alden, R.W., III, S.B. Weisberg, J.A. Ranasinghe, and D.M. Dauer. 1997. Optimizing temporal 

sampling strategies for benthic environmental monitoring programs. Mar. Pollut. Bull.

34:913-922. 

Clarke, K.R. 1993. Non-parametric multivariate analysis of changes in community structure. 

Aust. J. Ecol. 18:117-143. 

Daan, R., H. van Het Groenewoud, S.A. de Jong, and M. Mulder. 1992. Physio-chemical and 

biological features of a drilling site in the North Sea, 1 year after discharges of oilcontaminated drill cuttings. Mar. Ecol. Prog. Ser. 91:37-45. 

Dauer, D.M. 1993. Biological criteria, environmental health and estuarine macrobenthic 

community structure. Mar. Pollut. Bull. 26:249-257. 

Diaz, R.J. 1994. Response of tidal freshwater macrobenthos to sediment disturbance. 

Hydrobiologia. 278:201-212. 

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

and the behavioural responses of benthic macrofauna. Ocean. Mar. Biol. Ann. Rev.

33:245-303. 

Folk, R.L. 1980. Petrology of Sedimentary Rocks. Hemphill Publishing, Austin, TX. 

Gray, J.S. 1979. Pollution-induced changes in populations. Phil. Trans. R. Soc. Lond. B. 

286:545-561. 

Gray, J.S., K.R. Clarke, R.M. Warwick, and G. Hobbs. 1990. Detection of initial effects of 

pollution on marine benthos: An example from the Ekofisk and Eldfisk oilfields, North 

Sea. Mar. Ecol. Prog. Ser. 66:285-299. 

Harriott, S. 2000. Swanson Creek Wetland Characterization and Vegetation Species 

Identification. Prepared for Maryland Department of Natural Resources, Power Plant 

Research Program, by Versar, Inc., Columbia, MD. 
References 

5-2 

McGuinness, K.A. 1990. Effects of oil spills on macroinvertebrates of saltmarshes and 

mangrove forests in Botany Bay, New South Wales, Australia. J. Exp. Mar. Biol. Ecol.

142:121-136. 

Pearson, T.H. and R. Rosenberg. 1978. Macrobenthic succession in relation to organic 

enrichment and pollution of the marine environment. Oceanogr. Mar. Biol. Ann. Rev.

16:229-311. 

Peterson, C.H., M.C. Kennicutt, II, R.H. Green, P. Montagna, D.E. Harper, Jr., E.N. Powell, and 

P.F. Roscigno. 1996. Ecological consequences of environmental perturbations 

associated with offshore hydrocarbon production: a perspective on long-term exposures 

in the Gulf of Mexico. Can. J. Fish. Aquat. Sci. 53:2637-2654. 

Samiullah, Y. 1985. Biological effects of marine oil pollution. Oil and Petrochemical Pollution

2:235-264. 

Stewart-Oaten, A., W.W. Murdoch, and K.R. Parker. 1986. Environmental impact assessment: 

“Pseudoreplication” in time. Ecology 67:929-940. 

Underwood, A.J. 1991. Beyond BACI: Experimental designs for detecting human 

environmental impacts on temporal variations in natural populations. Aust. J. Mar. 

Freshwater Res. 42:569-587. 

Warwick, R.M. 1986. A new method for detecting pollution effects on marine macrobenthic 

communities. Mar. Biol. 92:557-562. 

Weisberg, S.B., J.A. Ranasinghe, D.M. Dauer, L.C. Schaffner, R.J. Diaz, and J.B. Frithsen. 

1997. An estuarine benthic index of biotic integrity (B-IBI) for Chesapeake Bay. 

Estuaries 20:149-158.

Wilson, J.G. and D.W. Jeffrey. 1994. Benthic biological pollution indices in estuaries. Pages 

311-327. In: J.M. Kramer (ed.), Biomonitoring of Coastal Waters and Estuaries. CRC 

Press, Boca Raton, Florida. 
Appendix A

A-1

APPENDIX A

BOTTOM ENVIRONMENT AND

BENTHOS SPRING
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: HC-01  | Location: Hunting Creek Habitat: Low Mesohaline Date: June 30, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.0 Salinity (ppt): 5.6 Temperature (C): 2 | Dissolved Oxygen (mg/l): 3.06 Sediment Silt-Clay (%): 93.55 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 1.99 Pollution Indicative Species Abundance (%) 44 | Abundance (#/m2) 2829 Pollution Indicative Species Biomass (%) 14 | Biomass (g/m2) 0.49 Pollution Sensitive Species Abundance (%) 9 | Carnivore-Omnivore Abundance (%) 3.25 Pollution Sensitive Species Biomass (%) 69 | Deep Deposit Feeder Abundance (%) 8.13  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 1242 | 1242.0 1242 12 | Leptocheirus plumulosus | 1012 | 1012.0 1012 10 | Tubificoides spp. | 230 | 230.0 230 2 | Rangia cuneata | 138 | 138.0 138 1 | Marenzelleria viridis | 92 | 92.0 92  | Cyathura polita | 46 | 46.0 46  | Neomysis americana (Epi) | 23 | 23.0 23  | Carinoma tremaphoros | 23 | 23.0 23  | Littoridinops tenuipes (Epi) | 23 | 23.0 23  | Coelotanypus spp. | 23 | 23.0 23  | Ameroculodes species complex | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ---------------------------------------------------------------------------------------------------------

| Total Abundance | 2875 | 

 | Total Abundance (w/o Epifauna) | 2829 |  | Number of Taxa | 11 |  | Number of Taxa (w/o Epifauna) | 9 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Marenzelleria viridis | 0.2530 | 0.2530 0.2530 0.2 | Leptocheirus plumulosus | 0.0644 | 0.0644 0.0644 0.0 | Rangia cuneata | 0.0529 | 0.0529 0.0529 0.0 | Streblospio benedicti | 0.0483 | 0.0483 0.0483 0.0 | Cyathura polita | 0.0322 | 0.0322 0.0322 0.0 | Coelotanypus spp. | 0.0207 | 0.0207 0.0207 0.0 | Carinoma tremaphoros | 0.0115 | 0.0115 0.0115 0.0 | Littoridinops tenuipes (Epi) | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Ameroculodes species complex | 0.0023 | 0.0023 0.0023 0.0 | Neomysis americana (Epi) | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 0.4957 |  | Total Biomass (w/o Epifauna) | 0.4876 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: HC-02  | Location: Hunting Creek Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.0 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 96.21 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.84 Pollution Indicative Species Abundance (%) 16 | Abundance (#/m2) 1909 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 2.25 Pollution Sensitive Species Abundance (%) 22 | Carnivore-Omnivore Abundance (%) 9.64 Pollution Sensitive Species Biomass (%) 61 | Deep Deposit Feeder Abundance (%) 12.05  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 759 | 759.0 759 7 | Streblospio benedicti | 299 | 299.0 299 2 | Tubificoides spp. | 207 | 207.0 207 2 | Macoma balthica | 161 | 161.0 161 1 | Rangia cuneata | 138 | 138.0 138 1 | Marenzelleria viridis | 69 | 69.0 69  | Cyathura polita | 69 | 69.0 69  | Carinoma tremaphoros | 46 | 46.0 46  | Littoridinops tenuipes (Epi) | 46 | 46.0 46  | Neanthes succinea | 46 | 46.0 46  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC ABUNDANCE (per sq. meter) - Contd.  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma mitchelli | 46 | 46.0 46  | Hypereteone heteropoda | 23 | 23.0 23  | Heteromastus filiformis | 23 | 23.0 23  | Leucon americanus | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------

| Total Abundance | 1955 | 

 | Total Abundance (w/o Epifauna) | 1909 |  | Number of Taxa | 14 |  | Number of Taxa (w/o Epifauna) | 13 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 1.1017 | 1.1017 1.1017 1.1 | Macoma mitchelli | 0.7406 | 0.7406 0.7406 0.7 | Marenzelleria viridis | 0.2024 | 0.2024 0.2024 0.2 | Leptocheirus plumulosus | 0.0851 | 0.0851 0.0851 0.0 | Rangia cuneata | 0.0437 | 0.0437 0.0437 0.0 | Cyathura polita | 0.0391 | 0.0391 0.0391 0.0 | Streblospio benedicti | 0.0138 | 0.0138 0.0138 0.0 | Carinoma tremaphoros | 0.0092 | 0.0092 0.0092 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Littoridinops tenuipes (Epi) | 0.0046 | 0.0046 0.0046 0.0 | Neanthes succinea | 0.0046 | 0.0046 0.0046 0.0 | Hypereteone heteropoda | 0.0012 | 0.0012 0.0012 0.0 | Heteromastus filiformis | 0.0012 | 0.0012 0.0012 0.0 | Leucon americanus | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 2.2483 |  | Total Biomass (w/o Epifauna) | 2.2438 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: HC-03  | Location: Hunting Creek Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.0 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 94.71 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.47 Pollution Indicative Species Abundance (%) 42 | Abundance (#/m2) 2116 Pollution Indicative Species Biomass (%) 1 | Biomass (g/m2) 1.92 Pollution Sensitive Species Abundance (%) 9 | Carnivore-Omnivore Abundance (%) 10.87 Pollution Sensitive Species Biomass (%) 60 | Deep Deposit Feeder Abundance (%) 15.22  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 851 | 851.0 851 8 | Leptocheirus plumulosus | 552 | 552.0 552 5 | Tubificoides spp. | 299 | 299.0 299 2 | Littoridinops tenuipes (Epi) | 138 | 138.0 138 1 | Cyathura polita | 115 | 115.0 115 1 | Macoma balthica | 69 | 69.0 69  | Hypereteone heteropoda | 46 | 46.0 46  | Neanthes succinea | 46 | 46.0 46  | Ameroculodes species complex | 46 | 46.0 46  | Carinoma tremaphoros | 23 | 23.0 23  | Heteromastus filiformis | 23 | 23.0 23  | Melita nitida (Epi) | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  | Rangia cuneata | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | Total Abundance | 2277 |  | Total Abundance (w/o Epifauna) | 2116 |  | Number of Taxa | 14 |  | Number of Taxa (w/o Epifauna) | 12 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 1.0971 | 1.0971 1.0971 1.0 | Macoma mitchelli | 0.4347 | 0.4347 0.4347 0.4 | Neanthes succinea | 0.2323 | 0.2323 0.2323 0.2 | Cyathura polita | 0.0529 | 0.0529 0.0529 0.0 | Leptocheirus plumulosus | 0.0368 | 0.0368 0.0368 0.0 | Streblospio benedicti | 0.0299 | 0.0299 0.0299 0.0 | Littoridinops tenuipes (Epi) | 0.0161 | 0.0161 0.0161 0.0 | Carinoma tremaphoros | 0.0069 | 0.0069 0.0069 0.0 | Ameroculodes species complex | 0.0069 | 0.0069 0.0069 0.0 | Rangia cuneata | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Heteromastus filiformis | 0.0046 | 0.0046 0.0046 0.0 | Hypereteone heteropoda | 0.0023 | 0.0023 0.0023 0.0 | Melita nitida (Epi) | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.9332 |  | Total Biomass (w/o Epifauna) | 1.9159 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: HC-04  | Location: Hunting Creek Habitat: Low Mesohaline Date: June 30, 2 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.2 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 86.05 Total Carbon (%):2 ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.14 Pollution Indicative Species Abundance (%) 37 | Abundance (#/m2) 1771 Pollution Indicative Species Biomass (%) 10 | Biomass (g/m2) 0.25 Pollution Sensitive Species Abundance (%) 9 | Carnivore-Omnivore Abundance (%) 2.60 Pollution Sensitive Species Biomass (%) 63 | Deep Deposit Feeder Abundance (%) 16.88  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 667 | 667.0 667 6 | Leptocheirus plumulosus | 598 | 598.0 598 5 | Tubificoides spp. | 299 | 299.0 299 2 | Littoridinops tenuipes (Epi) | 69 | 69.0 69  | Rangia cuneata | 69 | 69.0 69  | Cyathura polita | 46 | 46.0 46  | Marenzelleria viridis | 23 | 23.0 23  | Ameroculodes species complex | 23 | 23.0 23  | Leucon americanus | 23 | 23.0 23  | Macoma balthica | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 1840 |  | Total Abundance (w/o Epifauna) | 1771 |  | Number of Taxa | 10 |  | Number of Taxa (w/o Epifauna) | 9 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 0.1127 | 0.1127 0.1127 0.1 | Leptocheirus plumulosus | 0.0529 | 0.0529 0.0529 0.0 | Melita nitida (Epi) | 0.0322 | 0.0322 0.0322 0.0 | Marenzelleria viridis | 0.0276 | 0.0276 0.0276 0.0 | Streblospio benedicti | 0.0276 | 0.0276 0.0276 0.0 | Rangia cuneata | 0.0207 | 0.0207 0.0207 0.0 | Littoridinops tenuipes (Epi) | 0.0161 | 0.0161 0.0161 0.0 | Tubificoides spp. | 0.0069 | 0.0069 0.0069 0.0 | Ameroculodes species complex | 0.0023 | 0.0023 0.0023 0.0 | Leucon americanus | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 0.3003 |  | Total Biomass (w/o Epifauna) | 0.2842 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: HC-05  | Location: Hunting Creek Habitat: Low Mesohaline Date: June 30, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.7 Salinity (ppt): 4.6 Temperature (C): 2 | Dissolved Oxygen (mg/l): 3.6 Sediment Silt-Clay (%): 54.99 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.16 Pollution Indicative Species Abundance (%) 30 | Abundance (#/m2) 4830 Pollution Indicative Species Biomass (%) 3 | Biomass (g/m2) 1.37 Pollution Sensitive Species Abundance (%) 9 | Carnivore-Omnivore Abundance (%) 9.05 Pollution Sensitive Species Biomass (%) 23 | Deep Deposit Feeder Abundance (%) 7.62  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 2231 | 2231.0 2231 22 | Streblospio benedicti | 1495 | 1495.0 1495 14 | Cyathura polita | 299 | 299.0 299 2 | Tubificoides spp. | 230 | 230.0 230 2 | Rangia cuneata | 161 | 161.0 161 1 | Heteromastus filiformis | 138 | 138.0 138 1 | Carinoma tremaphoros | 115 | 115.0 115 1 | Ameroculodes species complex | 69 | 69.0 69  | Apocorophium lacustre (Epi) | 46 | 46.0 46  | Hobsonia florida | 46 | 46.0 46  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC ABUNDANCE (per sq. meter) - Contd.  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Edwardsia elegans | 23 | 23.0 23  | Melita nitida (Epi) | 23 | 23.0 23  | Edotea triloba (Epi) | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 4922 |  | Total Abundance (w/o Epifauna) | 4830 |  | Number of Taxa | 14 |  | Number of Taxa (w/o Epifauna) | 11 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma mitchelli | 0.6072 | 0.6072 0.6072 0.6 | Cyathura polita | 0.2369 | 0.2369 0.2369 0.2 | Leptocheirus plumulosus | 0.2323 | 0.2323 0.2323 0.2 | Heteromastus filiformis | 0.1012 | 0.1012 0.1012 0.1 | Rangia cuneata | 0.0874 | 0.0874 0.0874 0.0 | Carinoma tremaphoros | 0.0506 | 0.0506 0.0506 0.0 | Streblospio benedicti | 0.0460 | 0.0460 0.0460 0.0 | Melita nitida (Epi) | 0.0046 | 0.0046 0.0046 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Ameroculodes species complex | 0.0046 | 0.0046 0.0046 0.0 | Apocorophium lacustre (Epi) | 0.0046 | 0.0046 0.0046 0.0 | Edotea triloba (Epi) | 0.0023 | 0.0023 0.0023 0.0 | Hobsonia florida | 0.0023 | 0.0023 0.0023 0.0 | Edwardsia elegans | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.3858 |  | Total Biomass (w/o Epifauna) | 1.3743 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: HC-06  | Location: Hunting Creek Habitat: Low Mesohaline Date: June 30, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.2 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 96.72 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.56 Pollution Indicative Species Abundance (%) 0 | Abundance (#/m2) 1932 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 5.65 Pollution Sensitive Species Abundance (%) 44 | Carnivore-Omnivore Abundance (%) 19.05 Pollution Sensitive Species Biomass (%) 83 | Deep Deposit Feeder Abundance (%) 4.76  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 667 | 667.0 667 6 | Macoma balthica | 483 | 483.0 483 4 | Rangia cuneata | 276 | 276.0 276 2 | Neanthes succinea | 161 | 161.0 161 1 | Carinoma tremaphoros | 115 | 115.0 115 1 | Cyathura polita | 92 | 92.0 92  | Heteromastus filiformis | 69 | 69.0 69  | Macoma mitchelli | 46 | 46.0 46  | Tubificoides spp. | 23 | 23.0 23  | Neomysis americana (Epi) | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 1955 |  | Total Abundance (w/o Epifauna) | 1932 |  | Number of Taxa | 10 |  | Number of Taxa (w/o Epifauna) | 9 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter) -  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 4.4850 | 4.4850 4.4850 4.4 | Macoma mitchelli | 0.7061 | 0.7061 0.7061 0.7 | Cyathura polita | 0.1610 | 0.1610 0.1610 0.1 | Leptocheirus plumulosus | 0.1403 | 0.1403 0.1403 0.1 | Neanthes succinea | 0.0713 | 0.0713 0.0713 0.0 | Rangia cuneata | 0.0529 | 0.0529 0.0529 0.0 | Carinoma tremaphoros | 0.0276 | 0.0276 0.0276 0.0 | Neomysis americana (Epi) | 0.0092 | 0.0092 0.0092 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Heteromastus filiformis | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 5.6558 |  | Total Biomass (w/o Epifauna) | 5.6467 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: HC-07  | Location: Hunting Creek Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.0 Salinity (ppt): 5.4 Temperature (C): 2 | Dissolved Oxygen (mg/l): 2.31 Sediment Silt-Clay (%): 96.30 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.26 Pollution Indicative Species Abundance (%) 38 | Abundance (#/m2) 4577 Pollution Indicative Species Biomass (%) 2 | Biomass (g/m2) 1.39 Pollution Sensitive Species Abundance (%) 13 | Carnivore-Omnivore Abundance (%) 6.03 Pollution Sensitive Species Biomass (%) 84 | Deep Deposit Feeder Abundance (%) 9.55  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 1748 | 1748.0 1748 17 | Leptocheirus plumulosus | 1564 | 1564.0 1564 15 | Tubificoides spp. | 437 | 437.0 437 4 | Marenzelleria viridis | 299 | 299.0 299 2 | Rangia cuneata | 161 | 161.0 161 1 | Cyathura polita | 138 | 138.0 138 1 | Carinoma tremaphoros | 115 | 115.0 115 1 | Littoridinops tenuipes (Epi) | 115 | 115.0 115 1 | Ameroculodes species complex | 69 | 69.0 69  | Edotea triloba (Epi) | 69 | 69.0 69  | Edwardsia elegans | 23 | 23.0 23  | Americamysis almyra (Epi) | 23 | 23.0 23  | Macoma balthica | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 -------------------------------------------------------------------------------------------------------- | Total Abundance | 4784 |  | Total Abundance (w/o Epifauna) | 4577 |  | Number of Taxa | 13 |  | Number of Taxa (w/o Epifauna) | 10 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Marenzelleria viridis | 0.7222 | 0.7222 0.7222 0.7 | Macoma balthica | 0.2691 | 0.2691 0.2691 0.2 | Leptocheirus plumulosus | 0.1150 | 0.1150 0.1150 0.1 | Cyathura polita | 0.1081 | 0.1081 0.1081 0.1 | Rangia cuneata | 0.0759 | 0.0759 0.0759 0.0 | Carinoma tremaphoros | 0.0437 | 0.0437 0.0437 0.0 | Streblospio benedicti | 0.0414 | 0.0414 0.0414 0.0 | Littoridinops tenuipes (Epi) | 0.0184 | 0.0184 0.0184 0.0 | Tubificoides spp. | 0.0092 | 0.0092 0.0092 0.0 | Americamysis almyra (Epi) | 0.0069 | 0.0069 0.0069 0.0 | Edwardsia elegans | 0.0046 | 0.0046 0.0046 0.0 | Edotea triloba (Epi) | 0.0046 | 0.0046 0.0046 0.0 | Ameroculodes species complex | 0.0046 | 0.0046 0.0046 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.4235 |  | Total Biomass (w/o Epifauna) | 1.3936 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: HC-08  | Location: Hunting Creek Habitat: Low Mesohaline Date: June 30, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.0 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 95.30 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.84 Pollution Indicative Species Abundance (%) 16 | Abundance (#/m2) 1909 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 2.01 Pollution Sensitive Species Abundance (%) 25 | Carnivore-Omnivore Abundance (%) 16.87 Pollution Sensitive Species Biomass (%) 94 | Deep Deposit Feeder Abundance (%) 19.28  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 552 | 552.0 552 5 | Tubificoides spp. | 368 | 368.0 368 3 | Streblospio benedicti | 299 | 299.0 299 2 | Macoma balthica | 207 | 207.0 207 2 | Carinoma tremaphoros | 138 | 138.0 138 1 | Rangia cuneata | 138 | 138.0 138 1 | Cyathura polita | 115 | 115.0 115 1 | Edwardsia elegans | 23 | 23.0 23  | Hypereteone heteropoda | 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  | Procladius spp. | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | Total Abundance | 1909 |  | Total Abundance (w/o Epifauna) | 1909 |  | Number of Taxa | 11 |  | Number of Taxa (w/o Epifauna) | 11 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 1.5571 | 1.5571 1.5571 1.5 | Cyathura polita | 0.1909 | 0.1909 0.1909 0.1 | Marenzelleria viridis | 0.0874 | 0.0874 0.0874 0.0 | Leptocheirus plumulosus | 0.0621 | 0.0621 0.0621 0.0 | Rangia cuneata | 0.0552 | 0.0552 0.0552 0.0 | Carinoma tremaphoros | 0.0460 | 0.0460 0.0460 0.0 | Streblospio benedicti | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Edwardsia elegans | 0.0012 | 0.0012 0.0012 0.0 | Hypereteone heteropoda | 0.0012 | 0.0012 0.0012 0.0 | Chironomidae larvae | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 2.0115 |  | Total Biomass (w/o Epifauna) | 2.0115 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: HC-09  | Location: Hunting Creek Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.8 Salinity (ppt): 4.9 Temperature (C): 2 | Dissolved Oxygen (mg/l): 4.5 Sediment Silt-Clay (%): 89.80 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.10 Pollution Indicative Species Abundance (%) 13 | Abundance (#/m2) 3496 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 2.35 Pollution Sensitive Species Abundance (%) 19 | Carnivore-Omnivore Abundance (%) 5.92 Pollution Sensitive Species Biomass (%) 68 | Deep Deposit Feeder Abundance (%) 9.21  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 1932 | 1932.0 1932 19 | Rangia cuneata | 506 | 506.0 506 5 | Streblospio benedicti | 460 | 460.0 460 4 | Tubificoides spp. | 230 | 230.0 230 2 | Cyathura polita | 138 | 138.0 138 1 | Heteromastus filiformis | 92 | 92.0 92  | Neanthes succinea | 46 | 46.0 46  | Edotea triloba (Epi) | 46 | 46.0 46  | Macoma mitchelli | 46 | 46.0 46  | Carinoma tremaphoros | 23 | 23.0 23  | Melita nitida (Epi) | 23 | 23.0 23  | Macoma balthica | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | Total Abundance | 3565 |  | Total Abundance (w/o Epifauna) | 3495 |  | Number of Taxa | 12 |  | Number of Taxa (w/o Epifauna) | 10 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 1.2604 | 1.2604 1.2604 1.2 | Neanthes succinea | 0.3174 | 0.3174 0.3174 0.3 | Rangia cuneata | 0.2346 | 0.2346 0.2346 0.2 | Leptocheirus plumulosus | 0.2001 | 0.2001 0.2001 0.2 | Macoma mitchelli | 0.1495 | 0.1495 0.1495 0.1 | Cyathura polita | 0.1127 | 0.1127 0.1127 0.1 | Carinoma tremaphoros | 0.0345 | 0.0345 0.0345 0.0 | Edotea triloba (Epi) | 0.0207 | 0.0207 0.0207 0.0 | Streblospio benedicti | 0.0184 | 0.0184 0.0184 0.0 | Heteromastus filiformis | 0.0184 | 0.0184 0.0184 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Melita nitida (Epi) | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 2.3725 |  | Total Biomass (w/o Epifauna) | 2.3506 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: HC-10  | Location: Hunting Creek Habitat: Low Mesohaline Date: June 30, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.0 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 95.35 Total Carbon (%):2 ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.36 Pollution Indicative Species Abundance (%) 29 | Abundance (#/m2) 1472 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 1.07 Pollution Sensitive Species Abundance (%) 17 | Carnivore-Omnivore Abundance (%) 4.69 Pollution Sensitive Species Biomass (%) 90 | Deep Deposit Feeder Abundance (%) 10.94  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 575 | 575.0 575 5 | Streblospio benedicti | 437 | 437.0 437 4 | Tubificoides spp. | 161 | 161.0 161 1 | Littoridinops tenuipes (Epi) | 138 | 138.0 138 1 | Macoma balthica | 92 | 92.0 92  | Rangia cuneata | 69 | 69.0 69  | Marenzelleria viridis | 46 | 46.0 46  | Cyathura polita | 46 | 46.0 46  | Carinoma tremaphoros | 23 | 23.0 23  | Americamysis almyra (Epi) | 23 | 23.0 23  | Melita nitida (Epi) | 23 | 23.0 23  | Ameroculodes species complex | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | Total Abundance | 1656 |  | Total Abundance (w/o Epifauna) | 1472 |  | Number of Taxa | 12 |  | Number of Taxa (w/o Epifauna) | 9 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 0.8073 | 0.8073 0.8073 0.8 | Leptocheirus plumulosus | 0.0782 | 0.0782 0.0782 0.0 | Cyathura polita | 0.0782 | 0.0782 0.0782 0.0 | Marenzelleria viridis | 0.0621 | 0.0621 0.0621 0.0 | Rangia cuneata | 0.0230 | 0.0230 0.0230 0.0 | Littoridinops tenuipes (Epi) | 0.0161 | 0.0161 0.0161 0.0 | Streblospio benedicti | 0.0092 | 0.0092 0.0092 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Carinoma tremaphoros | 0.0046 | 0.0046 0.0046 0.0 | Americamysis almyra (Epi) | 0.0023 | 0.0023 0.0023 0.0 | Melita nitida (Epi) | 0.0012 | 0.0012 0.0012 0.0 | Ameroculodes species complex | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.0880 |  | Total Biomass (w/o Epifauna) | 1.0684 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: HIS-074  | Location: LTB Fixed Site Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 3.4 Salinity (ppt): 7.2 Temperature (C): 2 | Dissolved Oxygen (mg/l):2.8 Sediment Silt-Clay (%): 90.64 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.04 Pollution Indicative Species Abundance (%) 5 | Abundance (#/m2) 1748 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 4.20 Pollution Sensitive Species Abundance (%) 23 | Carnivore-Omnivore Abundance (%) 15.79 Pollution Sensitive Species Biomass (%) 88 | Deep Deposit Feeder Abundance (%) 55.26  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 943 | 943.0 943 9 | Macoma balthica | 414 | 414.0 414 4 | Carinoma tremaphoros | 138 | 138.0 138 1 | Hypereteone heteropoda | 69 | 69.0 69  | Neanthes succinea | 69 | 69.0 69  | Heteromastus filiformis | 23 | 23.0 23  | Streblospio benedicti | 23 | 23.0 23  | Leptocheirus plumulosus | 23 | 23.0 23  | Ameroculodes species complex | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 (Station: H --------------------------------------------------------------------------------------------------------- | Total Abundance | 1748 |  | Total Abundance (w/o Epifauna) | 1748 |  | Number of Taxa | 10 |  | Number of Taxa (w/o Epifauna) | 10 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter) .  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 3.6961 | 3.6961 3.6961 3.6 | Macoma mitchelli | 0.2967 | 0.2967 0.2967 0.2 | Carinoma tremaphoros | 0.1196 | 0.1196 0.1196 0.1 | Neanthes succinea | 0.0621 | 0.0621 0.0621 0.0 | Tubificoides spp. | 0.0115 | 0.0115 0.0115 0.0 | Hypereteone heteropoda | 0.0069 | 0.0069 0.0069 0.0 | Heteromastus filiformis | 0.0023 | 0.0023 0.0023 0.0 | Ameroculodes species complex | 0.0023 | 0.0023 0.0023 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Leptocheirus plumulosus | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 4.1999 |  | Total Biomass (w/o Epifauna) | 4.1999 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: PR-01  | Location: Patuxent River Habitat: Low Mesohaline Date: June 30, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 4.7 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 98.13 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.67 Pollution Indicative Species Abundance (%) 16 | Abundance (#/m2) 414 Pollution Indicative Species Biomass (%) 1 | Biomass (g/m2) 0.95 Pollution Sensitive Species Abundance (%) 22 | Carnivore-Omnivore Abundance (%) 33.33 Pollution Sensitive Species Biomass (%) 73 | Deep Deposit Feeder Abundance (%) 22.22  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 92 | 92.0 92  | Tubificoides spp. | 69 | 69.0 69  | Carinoma tremaphoros | 69 | 69.0 69  | Hypereteone heteropoda | 69 | 69.0 69  | Leptocheirus plumulosus | 69 | 69.0 69  | Heteromastus filiformis | 23 | 23.0 23  | Leucon americanus | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 414 |  | Total Abundance (w/o Epifauna) | 414 |  | Number of Taxa | 7 |  | Number of Taxa (w/o Epifauna) | 7 |  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter) -  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 0.6969 | 0.6969 0.6969 0.6 | Heteromastus filiformis | 0.1058 | 0.1058 0.1058 0.1 | Carinoma tremaphoros | 0.0943 | 0.0943 0.0943 0.0 | Leptocheirus plumulosus | 0.0322 | 0.0322 0.0322 0.0 | Hypereteone heteropoda | 0.0161 | 0.0161 0.0161 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Leucon americanus | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 0.9488 |  | Total Biomass (w/o Epifauna) | 0.9488 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: PR-02  | Location: Patuxent River Habitat: Low Mesohaline Date: June 30, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 3.1 Salinity (ppt): 9.7 Temperature (C): 2 | Dissolved Oxygen (mg/l):0.61 Sediment Silt-Clay (%): 70.27 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.39 Pollution Indicative Species Abundance (%) 23 | Abundance (#/m2) 483 Pollution Indicative Species Biomass (%) 1 | Biomass (g/m2) 1.11 Pollution Sensitive Species Abundance (%) 47 | Carnivore-Omnivore Abundance (%) 23.81 Pollution Sensitive Species Biomass (%) 97 | Deep Deposit Feeder Abundance (%) 14.29  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 230 | 230.0 230 2 | Hypereteone heteropoda | 69 | 69.0 69  | Tubificoides spp. | 46 | 46.0 46  | Carinoma tremaphoros | 46 | 46.0 46  | Imm. Tubificid w/o Cap. Chaete | 23 | 23.0 23  | Streblospio benedicti | 23 | 23.0 23  | Mucrogammarus mucronatus (Epi| 23 | 23.0 23  | Ameroculodes species complex | 23 | 23.0 23  | Leucon americanus | 23 | 23.0 23  | Ischadium recurvum (Epi) | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | Total Abundance | 529 |  | Total Abundance (w/o Epifauna) | 483 |  | Number of Taxa | 10 |  | Number of Taxa (w/o Epifauna) | 8 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 1.0810 | 1.0810 1.0810 1.0 | Ischadium recurvum (Epi) | 0.0230 | 0.0230 0.0230 0.0 | Carinoma tremaphoros | 0.0138 | 0.0138 0.0138 0.0 | Hypereteone heteropoda | 0.0115 | 0.0115 0.0115 0.0 | Mucrogammarus mucronatus (Epi| 0.0023 | 0.0023 0.0023 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Ameroculodes species complex | 0.0012 | 0.0012 0.0012 0.0 | Leucon americanus | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.1376 |  | Total Biomass (w/o Epifauna) | 1.1123 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: PR-03  | Location: Patuxent River Habitat: Low Mesohaline Date: June 30, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 3.5 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 92.37 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.51 Pollution Indicative Species Abundance (%) 6 | Abundance (#/m2) 667 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 1.74 Pollution Sensitive Species Abundance (%) 58 | Carnivore-Omnivore Abundance (%) 10.34 Pollution Sensitive Species Biomass (%) 72 | Deep Deposit Feeder Abundance (%) 10.34  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 322 | 322.0 322 3 | Leptocheirus plumulosus | 92 | 92.0 92  | Tubificoides spp. | 69 | 69.0 69  | Rangia cuneata | 46 | 46.0 46  | Edwardsia elegans | 23 | 23.0 23  | Carinoma tremaphoros | 23 | 23.0 23  | Hypereteone heteropoda | 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  | Streblospio benedicti | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 667 |  | Total Abundance (w/o Epifauna) | 667 |  | Number of Taxa | 10 |  | Number of Taxa (w/o Epifauna) | 10 |  ---------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter) - Contd.  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 1.0419 | 1.0419 1.0419 1.0 | Macoma mitchelli | 0.4324 | 0.4324 0.4324 0.4 | Marenzelleria viridis | 0.2001 | 0.2001 0.2001 0.2 | Carinoma tremaphoros | 0.0253 | 0.0253 0.0253 0.0 | Rangia cuneata | 0.0138 | 0.0138 0.0138 0.0 | Hypereteone heteropoda | 0.0115 | 0.0115 0.0115 0.0 | Leptocheirus plumulosus | 0.0046 | 0.0046 0.0046 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Streblospio benedicti | 0.0023 | 0.0023 0.0023 0.0 | Edwardsia elegans | 0.0023 | 0.0023 0.0023 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.7365 |  | Total Biomass (w/o Epifauna) | 1.7365 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: PR-04  | Location: Patuxent River Habitat: Low Mesohaline Date: June 30, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 2.3 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 89.90 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.58 Pollution Indicative Species Abundance (%) 4 | Abundance (#/m2) 966 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 2.76 Pollution Sensitive Species Abundance (%) 26 | Carnivore-Omnivore Abundance (%) 23.81 Pollution Sensitive Species Biomass (%) 59 | Deep Deposit Feeder Abundance (%) 11.90  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 391 | 391.0 391 3 | Macoma balthica | 138 | 138.0 138 1 | Cyathura polita | 115 | 115.0 115 1 | Macoma mitchelli | 92 | 92.0 92  | Tubificoides spp. | 69 | 69.0 69  | Carinoma tremaphoros | 69 | 69.0 69  | Hypereteone heteropoda | 46 | 46.0 46  | Heteromastus filiformis | 46 | 46.0 46  --------------------------------------------------------------------------------------------------------- | Total Abundance | 966 |  | Total Abundance (w/o Epifauna) | 966 |  | Number of Taxa | 8 |  | Number of Taxa (w/o Epifauna) | 8 |  ----------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter) - Contd.  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 1.4122 | 1.4122 1.4122 1.4 | Macoma mitchelli | 0.9936 | 0.9936 0.9936 0.9 | Cyathura polita | 0.2162 | 0.2162 0.2162 0.2 | Leptocheirus plumulosus | 0.1058 | 0.1058 0.1058 0.1 | Carinoma tremaphoros | 0.0184 | 0.0184 0.0184 0.0 | Hypereteone heteropoda | 0.0115 | 0.0115 0.0115 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Heteromastus filiformis | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 2.7601 |  | Total Biomass (w/o Epifauna) | 2.7601 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: PR-05  | Location: Patuxent River Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 3.8 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 88.23 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.17 Pollution Indicative Species Abundance (%) 13 | Abundance (#/m2) 1909 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 9.31 Pollution Sensitive Species Abundance (%) 53 | Carnivore-Omnivore Abundance (%) 8.43 Pollution Sensitive Species Biomass (%) 98 | Deep Deposit Feeder Abundance (%) 30.12  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 989 | 989.0 989 9 | Tubificoides spp. | 460 | 460.0 460 4 | Streblospio benedicti | 115 | 115.0 115 1 | Imm. Tubificid w/o Cap. Chaete | 92 | 92.0 92  | Neanthes succinea | 92 | 92.0 92  | Hypereteone heteropoda | 46 | 46.0 46  | Neomysis americana (Epi) | 23 | 23.0 23  | Carinoma tremaphoros | 23 | 23.0 23  | Heteromastus filiformis | 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  | Leptocheirus plumulosus | 23 | 23.0 23  | Ameroculodes species complex | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | Total Abundance | 1932 |  | Total Abundance (w/o Epifauna) | 1909 |  | Number of Taxa | 12 |  | Number of Taxa (w/o Epifauna) | 11 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 9.1126 | 9.1126 9.1126 9.1 | Neanthes succinea | 0.0920 | 0.0920 0.0920 0.0 | Marenzelleria viridis | 0.0644 | 0.0644 0.0644 0.0 | Neomysis americana (Epi) | 0.0207 | 0.0207 0.0207 0.0 | Heteromastus filiformis | 0.0115 | 0.0115 0.0115 0.0 | Tubificoides spp. | 0.0069 | 0.0069 0.0069 0.0 | Hypereteone heteropoda | 0.0046 | 0.0046 0.0046 0.0 | Leptocheirus plumulosus | 0.0046 | 0.0046 0.0046 0.0 | Carinoma tremaphoros | 0.0046 | 0.0046 0.0046 0.0 | Streblospio benedicti | 0.0046 | 0.0046 0.0046 0.0 | Ameroculodes species complex | 0.0023 | 0.0023 0.0023 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 9.3300 |  | Total Biomass (w/o Epifauna) | 9.3093 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: PR-06  | Location: Patuxent River Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 2.9 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 96.38 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.21 Pollution Indicative Species Abundance (%) 5 | Abundance (#/m2) 2001 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 4.08 Pollution Sensitive Species Abundance (%) 32 | Carnivore-Omnivore Abundance (%) 5.75 Pollution Sensitive Species Biomass (%) 90 | Deep Deposit Feeder Abundance (%) 50.57  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 920 | 920.0 920 9 | Macoma balthica | 552 | 552.0 552 5 | Leptocheirus plumulosus | 184 | 184.0 184 1 | Neanthes succinea | 92 | 92.0 92  | Streblospio benedicti | 69 | 69.0 69  | Rangia cuneata | 69 | 69.0 69  | Imm. Tubificid w/o Cap. Chaete | 46 | 46.0 46  | Heteromastus filiformis | 46 | 46.0 46  | Neomysis americana (Epi) | 23 | 23.0 23  | Cyathura polita | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | Total Abundance | 2024 |  | Total Abundance (w/o Epifauna) | 2001 |  | Number of Taxa | 10 |  | Number of Taxa (w/o Epifauna) | 9 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 3.6662 | 3.6662 3.6662 3.6 | Neanthes succinea | 0.3381 | 0.3381 0.3381 0.3 | Leptocheirus plumulosus | 0.0276 | 0.0276 0.0276 0.0 | Rangia cuneata | 0.0253 | 0.0253 0.0253 0.0 | Tubificoides spp. | 0.0092 | 0.0092 0.0092 0.0 | Neomysis americana (Epi) | 0.0069 | 0.0069 0.0069 0.0 | Heteromastus filiformis | 0.0069 | 0.0069 0.0069 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Cyathura polita | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 4.0838 |  | Total Biomass (w/o Epifauna) | 4.0769 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: PR-07  | Location: Patuxent River Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.8 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 91.97 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.42 Pollution Indicative Species Abundance (%) 2 | Abundance (#/m2) 3036 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 3.60 Pollution Sensitive Species Abundance (%) 28 | Carnivore-Omnivore Abundance (%) 12.88 Pollution Sensitive Species Biomass (%) 75 | Deep Deposit Feeder Abundance (%) 7.58  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 1564 | 1564.0 1564 15 | Macoma balthica | 345 | 345.0 345 3 | Rangia cuneata | 345 | 345.0 345 3 | Tubificoides spp. | 207 | 207.0 207 2 | Carinoma tremaphoros | 161 | 161.0 161 1 | Cyathura polita | 161 | 161.0 161 1 | Neanthes succinea | 69 | 69.0 69  | Streblospio benedicti | 69 | 69.0 69  | Ameroculodes species complex | 46 | 46.0 46  | Heteromastus filiformis | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC ABUNDANCE (per sq. meter) - Contd.  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Marenzelleria viridis | 23 | 23.0 23  | Edotea triloba (Epi) | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  | Apocorophium lacustre (Epi) | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 3082 |  | Total Abundance (w/o Epifauna) | 3036 |  | Number of Taxa | 14 |  | Number of Taxa (w/o Epifauna) | 12 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 2.4380 | 2.4380 2.4380 2.4 | Neanthes succinea | 0.3611 | 0.3611 0.3611 0.3 | Leptocheirus plumulosus | 0.2530 | 0.2530 0.2530 0.2 | Macoma mitchelli | 0.1656 | 0.1656 0.1656 0.1 | Cyathura polita | 0.1472 | 0.1472 0.1472 0.1 | Rangia cuneata | 0.1035 | 0.1035 0.1035 0.1 | Heteromastus filiformis | 0.0598 | 0.0598 0.0598 0.0 | Carinoma tremaphoros | 0.0437 | 0.0437 0.0437 0.0 | Marenzelleria viridis | 0.0207 | 0.0207 0.0207 0.0 | Ameroculodes species complex | 0.0046 | 0.0046 0.0046 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Edotea triloba (Epi) | 0.0012 | 0.0012 0.0012 0.0 | Apocorophium lacustre (Epi) | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 3.6019 |  | Total Biomass (w/o Epifauna) | 3.5995 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: PR-08  | Location: Patuxent River Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m):3.9 Salinity (ppt): 6.8 Temperature (C): 2 | Dissolved Oxygen (mg/l): 3.25 Sediment Silt-Clay (%): 88.63 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.90 Pollution Indicative Species Abundance (%) 13 | Abundance (#/m2) 1817 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 4.80 Pollution Sensitive Species Abundance (%) 24 | Carnivore-Omnivore Abundance (%) 21.52 Pollution Sensitive Species Biomass (%) 75 | Deep Deposit Feeder Abundance (%) 15.19  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 552 | 552.0 552 5 | Macoma balthica | 368 | 368.0 368 3 | Neanthes succinea | 230 | 230.0 230 2 | Carinoma tremaphoros | 161 | 161.0 161 1 | Streblospio benedicti | 138 | 138.0 138 1 | Imm. Tubificid w/o Cap. Chaete | 115 | 115.0 115 1 | Tubificoides spp. | 92 | 92.0 92  | Heteromastus filiformis | 69 | 69.0 69  | Rangia cuneata | 46 | 46.0 46  | Marenzelleria viridis | 23 | 23.0 23  | Edotea triloba (Epi) | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  -------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | Total Abundance | 1840 |  | Total Abundance (w/o Epifauna) | 1817 |  | Number of Taxa | 12 |  | Number of Taxa (w/o Epifauna) | 11 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 3.5880 | 3.5880 3.5880 3.5 | Neanthes succinea | 0.7935 | 0.7935 0.7935 0.7 | Macoma mitchelli | 0.1909 | 0.1909 0.1909 0.1 | Leptocheirus plumulosus | 0.1104 | 0.1104 0.1104 0.1 | Carinoma tremaphoros | 0.0483 | 0.0483 0.0483 0.0 | Heteromastus filiformis | 0.0253 | 0.0253 0.0253 0.0 | Marenzelleria viridis | 0.0184 | 0.0184 0.0184 0.0 | Rangia cuneata | 0.0115 | 0.0115 0.0115 0.0 | Streblospio benedicti | 0.0092 | 0.0092 0.0092 0.0 | Edotea triloba (Epi) | 0.0046 | 0.0046 0.0046 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 4.8036 |  | Total Biomass (w/o Epifauna) | 4.7990 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: PR-09  | Location: Patuxent River Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 2.5 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 93.55 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.93 Pollution Indicative Species Abundance (%) 20 | Abundance (#/m2) 920 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 4.78 Pollution Sensitive Species Abundance (%) 32 | Carnivore-Omnivore Abundance (%) 15.00 Pollution Sensitive Species Biomass (%) 93 | Deep Deposit Feeder Abundance (%) 30.00  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Heteromastus filiformis | 207 | 207.0 207 2 | Macoma balthica | 184 | 184.0 184 1 | Streblospio benedicti | 161 | 161.0 161 1 | Carinoma tremaphoros | 115 | 115.0 115 1 | Rangia cuneata | 92 | 92.0 92  | Tubificoides spp. | 46 | 46.0 46  | Leptocheirus plumulosus | 46 | 46.0 46  | Neomysis americana (Epi) | 23 | 23.0 23  | Imm. Tubificid w/o Cap. Chaete | 23 | 23.0 23  | Cyathura polita | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | Total Abundance | 943 |  | Total Abundance (w/o Epifauna) | 920 |  | Number of Taxa | 11 |  | Number of Taxa (w/o Epifauna) | 10 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 4.4045 | 4.4045 4.4045 4.4 | Macoma mitchelli | 0.2300 | 0.2300 0.2300 0.2 | Rangia cuneata | 0.0552 | 0.0552 0.0552 0.0 | Carinoma tremaphoros | 0.0414 | 0.0414 0.0414 0.0 | Streblospio benedicti | 0.0184 | 0.0184 0.0184 0.0 | Cyathura polita | 0.0115 | 0.0115 0.0115 0.0 | Neomysis americana (Epi) | 0.0092 | 0.0092 0.0092 0.0 | Leptocheirus plumulosus | 0.0069 | 0.0069 0.0069 0.0 | Heteromastus filiformis | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 4.7898 |  | Total Biomass (w/o Epifauna) | 4.7806 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: PR-10  | Location: Patuxent River Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 2.0 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 94.79 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.46 Pollution Indicative Species Abundance (%) 28 | Abundance (#/m2) 1219 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 46.59 Pollution Sensitive Species Abundance (%) 52 | Carnivore-Omnivore Abundance (%) 1.89 Pollution Sensitive Species Biomass (%) 99 | Deep Deposit Feeder Abundance (%) 13.21  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Rangia cuneata | 368 | 368.0 368 3 | Streblospio benedicti | 345 | 345.0 345 3 | Macoma balthica | 253 | 253.0 253 2 | Heteromastus filiformis | 92 | 92.0 92  | Tubificoides spp. | 69 | 69.0 69  | Littoridinops tenuipes (Epi) | 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  | Leptocheirus plumulosus | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  | Procladius spp. | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 1242 |  | Total Abundance (w/o Epifauna) | 1219 |  | Number of Taxa | 10 |  | Number of Taxa (w/o Epifauna) | 9 |  --------------------------------------------------------------------------------------------------------- Continued . . .
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Rangia cuneata | 45.3836 | 45.3836 45.3836 45.3 | Macoma balthica | 1.0281 | 1.0281 1.0281 1.0 | Macoma mitchelli | 0.0736 | 0.0736 0.0736 0.0 | Marenzelleria viridis | 0.0483 | 0.0483 0.0483 0.0 | Heteromastus filiformis | 0.0391 | 0.0391 0.0391 0.0 | Streblospio benedicti | 0.0138 | 0.0138 0.0138 0.0 | Leptocheirus plumulosus | 0.0046 | 0.0046 0.0046 0.0 | Littoridinops tenuipes (Epi) | 0.0046 | 0.0046 0.0046 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Chironomidae larvae | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 46.5981 |  | Total Biomass (w/o Epifauna) | 46.5935 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: PR-11  | Location: Patuxent River Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 4.7 Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 88.58 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 1.83 Pollution Indicative Species Abundance (%) 28 | Abundance (#/m2) 4462 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 3.01 Pollution Sensitive Species Abundance (%) 64 | Carnivore-Omnivore Abundance (%) 8.25 Pollution Sensitive Species Biomass (%) 91 | Deep Deposit Feeder Abundance (%) 2.58  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Apocorophium lacustre (Epi) | 10833 | 10833.0 10833 108 | Rangia cuneata | 2438 | 2438.0 2438 24 | Streblospio benedicti | 1288 | 1288.0 1288 12 | Littoridinops tenuipes (Epi) | 575 | 575.0 575 5 | Cyathura polita | 322 | 322.0 322 3 | Balanus improvisus (Epi) | 207 | 207.0 207 2 | Edotea triloba (Epi) | 161 | 161.0 161 1 | Gammarus daiberi (Epi) | 161 | 161.0 161 1 | Polydora cornuta | 115 | 115.0 115 1 | Tubificoides spp. | 92 | 92.0 92  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC ABUNDANCE (per sq. meter) - Contd.  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Marenzelleria viridis | 92 | 92.0 92  | Rhithropanopeus harrisi (Epi)| 69 | 69.0 69  | Neomysis americana (Epi) | 23 | 23.0 23  | Edwardsia elegans | 23 | 23.0 23  | Carinoma tremaphoros | 23 | 23.0 23  | Heteromastus filiformis | 23 | 23.0 23  | Macoma balthica | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  | Turbellaria (Epi) | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 16514 |  | Total Abundance (w/o Epifauna) | 4462 |  | Number of Taxa | 19 |  | Number of Taxa (w/o Epifauna) | 11 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Rangia cuneata | 2.3368 | 2.3368 2.3368 2.3 | Apocorophium lacustre (Epi) | 0.8004 | 0.8004 0.8004 0.8 | Cyathura polita | 0.2645 | 0.2645 0.2645 0.2 | Balanus improvisus (Epi) | 0.2208 | 0.2208 0.2208 0.2 | Rhithropanopeus harrisi (Epi)| 0.1702 | 0.1702 0.1702 0.1 | Macoma mitchelli | 0.1173 | 0.1173 0.1173 0.1 | Marenzelleria viridis | 0.1081 | 0.1081 0.1081 0.1 | Carinoma tremaphoros | 0.0920 | 0.0920 0.0920 0.0 | Gammarus spp. (Epi) | 0.0713 | 0.0713 0.0713 0.0 | Macoma balthica | 0.0529 | 0.0529 0.0529 0.0 | Littoridinops tenuipes (Epi) | 0.0414 | 0.0414 0.0414 0.0 | Edotea triloba (Epi) | 0.0345 | 0.0345 0.0345 0.0 | Streblospio benedicti | 0.0253 | 0.0253 0.0253 0.0 | Polydora cornuta | 0.0069 | 0.0069 0.0069 0.0 | Neomysis americana (Epi) | 0.0046 | 0.0046 0.0046 0.0 | Turbellaria (Epi) | 0.0046 | 0.0046 0.0046 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Edwardsia elegans | 0.0023 | 0.0023 0.0023 0.0 | Heteromastus filiformis | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 4.3574 |  | Total Biomass (w/o Epifauna) | 3.0096 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: PR-12  | Location: Patuxent River Habitat: Oligohaline Date: June 30, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m):5.8 Salinity (ppt): 3.2 Temperature (C): 2 | Dissolved Oxygen (mg/l): 3.12 Sediment Silt-Clay (%): 92.57 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.47 Pollution Indicative Species Abundance (%) 35 | Abundance (#/m2) 1817 Pollution Indicative Species Biomass (%) 7 | Biomass (g/m2) 0.29 Pollution Sensitive Species Abundance (%) 11 | Carnivore-Omnivore Abundance (%) 5.06 Pollution Sensitive Species Biomass (%) 42 | Deep Deposit Feeder Abundance (%) 24.05  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 621 | 621.0 621 6 | Tubificoides spp. | 437 | 437.0 437 4 | Ameroculodes species complex | 391 | 391.0 391 3 | Rangia cuneata | 161 | 161.0 161 1 | Carinoma tremaphoros | 69 | 69.0 69  | Littoridinops tenuipes (Epi) | 69 | 69.0 69  | Gammarus daiberi (Epi) | 69 | 69.0 69  | Apocorophium lacustre (Epi) | 46 | 46.0 46  | Marenzelleria viridis | 23 | 23.0 23  | Leptocheirus plumulosus | 23 | 23.0 23  | Macoma balthica | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  | Cryptochironomus spp. | 23 | 23.0 23  | Hobsonia florida | 23 | 23.0 23  -------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | Total Abundance | 2001 |  | Total Abundance (w/o Epifauna) | 1817 |  | Number of Taxa | 14 |  | Number of Taxa (w/o Epifauna) | 11 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Marenzelleria viridis | 0.0736 | 0.0736 0.0736 0.0 | Macoma mitchelli | 0.0483 | 0.0483 0.0483 0.0 | Rangia cuneata | 0.0483 | 0.0483 0.0483 0.0 | Carinoma tremaphoros | 0.0460 | 0.0460 0.0460 0.0 | Ameroculodes species complex | 0.0437 | 0.0437 0.0437 0.0 | Streblospio benedicti | 0.0207 | 0.0207 0.0207 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Apocorophium lacustre (Epi) | 0.0046 | 0.0046 0.0046 0.0 | Littoridinops tenuipes (Epi) | 0.0023 | 0.0023 0.0023 0.0 | Hobsonia florida | 0.0023 | 0.0023 0.0023 0.0 | Gammarus spp. (Epi) | 0.0023 | 0.0023 0.0023 0.0 | Leptocheirus plumulosus | 0.0012 | 0.0012 0.0012 0.0 | Macoma balthica | 0.0012 | 0.0012 0.0012 0.0 | Chironomidae larvae | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 0.3006 |  | Total Biomass (w/o Epifauna) | 0.2914 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: SC-01  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.1 Salinity (ppt): 5.9 Temperature (C): 2 | Dissolved Oxygen (mg/l): 6.0 Sediment Silt-Clay (%): 90.55 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 1.38 Pollution Indicative Species Abundance (%) 75 | Abundance (#/m2) 2185 Pollution Indicative Species Biomass (%) 5 | Biomass (g/m2) 1.14 Pollution Sensitive Species Abundance (%) 10 | Carnivore-Omnivore Abundance (%) 5.26 Pollution Sensitive Species Biomass (%) 31 | Deep Deposit Feeder Abundance (%) 8.42  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 1656 | 1656.0 1656 16 | Tubificoides spp. | 184 | 184.0 184 1 | Rangia cuneata | 115 | 115.0 115 1 | Carinoma tremaphoros | 69 | 69.0 69  | Marenzelleria viridis | 69 | 69.0 69  | Cyathura polita | 46 | 46.0 46  | Macoma mitchelli | 46 | 46.0 46  | Littoridinops tenuipes (Epi) | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 2208 |  | Total Abundance (w/o Epifauna) | 2185 |  | Number of Taxa | 8 |  | Number of Taxa (w/o Epifauna) | 7 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma mitchelli | 0.4255 | 0.4255 0.4255 0.4 | Carinoma tremaphoros | 0.2829 | 0.2829 0.2829 0.2 | Marenzelleria viridis | 0.2185 | 0.2185 0.2185 0.2 | Rangia cuneata | 0.0759 | 0.0759 0.0759 0.0 | Cyathura polita | 0.0690 | 0.0690 0.0690 0.0 | Streblospio benedicti | 0.0621 | 0.0621 0.0621 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Littoridinops tenuipes (Epi) | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.1374 |  | Total Biomass (w/o Epifauna) | 1.1362 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: SC-02  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: June 30, 20 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.7 Salinity (ppt): 4.2 Temperature (C): 2 | Dissolved Oxygen (mg/l): 8.13 Sediment Silt-Clay (%): 53.30 Total Carbon (%):1 ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 0.88 Pollution Indicative Species Abundance (%) 87 | Abundance (#/m2) 20401 Pollution Indicative Species Biomass (%) 45 | Biomass (g/m2) 1.58 Pollution Sensitive Species Abundance (%) 1 | Carnivore-Omnivore Abundance (%) 3.16 Pollution Sensitive Species Biomass (%) 36 | Deep Deposit Feeder Abundance (%) 4.62  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 17733 | 17733.0 17733 177 | Hobsonia florida | 966 | 966.0 966 9 | Tubificoides spp. | 874 | 874.0 874 8 | Cyathura polita | 299 | 299.0 299 2 | Procladius spp. | 115 | 115.0 115 1 | Carinoma tremaphoros | 92 | 92.0 92  | Edotea triloba (Epi) | 92 | 92.0 92  | Edwardsia elegans | 69 | 69.0 69  | Heteromastus filiformis | 69 | 69.0 69  | Marenzelleria viridis | 69 | 69.0 69  | Chironomus spp. | 46 | 46.0 46  | Neanthes succinea | 23 | 23.0 23  | Polydora cornuta | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | Total Abundance | 20493 |  | Total Abundance (w/o Epifauna) | 20401 |  | Number of Taxa | 14 |  | Number of Taxa (w/o Epifauna) | 13 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 0.7130 | 0.7130 0.7130 0.7 | Cyathura polita | 0.5428 | 0.5428 0.5428 0.5 | Hobsonia florida | 0.0989 | 0.0989 0.0989 0.0 | Heteromastus filiformis | 0.0897 | 0.0897 0.0897 0.0 | Carinoma tremaphoros | 0.0529 | 0.0529 0.0529 0.0 | Marenzelleria viridis | 0.0276 | 0.0276 0.0276 0.0 | Edotea triloba (Epi) | 0.0161 | 0.0161 0.0161 0.0 | Tubificoides spp. | 0.0138 | 0.0138 0.0138 0.0 | Edwardsia elegans | 0.0115 | 0.0115 0.0115 0.0 | Neanthes succinea | 0.0092 | 0.0092 0.0092 0.0 | Macoma mitchelli | 0.0092 | 0.0092 0.0092 0.0 | Polydora cornuta | 0.0069 | 0.0069 0.0069 0.0 | Chironomidae larvae | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.5928 |  | Total Biomass (w/o Epifauna) | 1.5767 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: SC-03  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: June 30, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.2 Salinity (ppt): 6.0 Temperature (C):27 | Dissolved Oxygen (mg/l): 5.62 Sediment Silt-Clay (%): 96.79 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.55 Pollution Indicative Species Abundance (%) 47 | Abundance (#/m2) 966 Pollution Indicative Species Biomass (%) 1 | Biomass (g/m2) 1.84 Pollution Sensitive Species Abundance (%) 28 | Carnivore-Omnivore Abundance (%) 19.05 Pollution Sensitive Species Biomass (%) 68 | Deep Deposit Feeder Abundance (%) 7.14  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 460 | 460.0 460 4 | Cyathura polita | 138 | 138.0 138 1 | Tubificoides spp. | 69 | 69.0 69  | Rangia cuneata | 69 | 69.0 69  | Carinoma tremaphoros | 46 | 46.0 46  | Marenzelleria viridis | 46 | 46.0 46  | Leptocheirus plumulosus | 46 | 46.0 46  | Macoma mitchelli | 46 | 46.0 46  | Ameroculodes species complex | 23 | 23.0 23  | Macoma balthica | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 966 |  | Total Abundance (w/o Epifauna) | 966 |  | Number of Taxa | 10 |  | Number of Taxa (w/o Epifauna) | 10 |  --------------------------------------------------------------------------------------------------------- Continued . . 
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter) - Contd.  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 0.9154 | 0.9154 0.9154 0.9 | Macoma mitchelli | 0.5244 | 0.5244 0.5244 0.5 | Cyathura polita | 0.2254 | 0.2254 0.2254 0.2 | Marenzelleria viridis | 0.0851 | 0.0851 0.0851 0.0 | Rangia cuneata | 0.0299 | 0.0299 0.0299 0.0 | Streblospio benedicti | 0.0253 | 0.0253 0.0253 0.0 | Carinoma tremaphoros | 0.0184 | 0.0184 0.0184 0.0 | Leptocheirus plumulosus | 0.0092 | 0.0092 0.0092 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Ameroculodes species complex | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.8355 |  | Total Biomass (w/o Epifauna) | 1.8355 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: SC-04  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.9 Salinity (ppt): 5.4 Temperature (C): 2 | Dissolved Oxygen (mg/l): 6.43 Sediment Silt-Clay (%): 9.98 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.14 Pollution Indicative Species Abundance (%) 18 | Abundance (#/m2) 1725 Pollution Indicative Species Biomass (%) 5 | Biomass (g/m2) 0.31 Pollution Sensitive Species Abundance (%) 16 | Carnivore-Omnivore Abundance (%) 6.67 Pollution Sensitive Species Biomass (%) 35 | Deep Deposit Feeder Abundance (%) 58.67  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Heteromastus filiformis | 943 | 943.0 943 9 | Streblospio benedicti | 322 | 322.0 322 3 | Marenzelleria viridis | 115 | 115.0 115 1 | Rangia cuneata | 115 | 115.0 115 1 | Tubificoides spp. | 69 | 69.0 69  | Edwardsia elegans | 46 | 46.0 46  | Leptocheirus plumulosus | 46 | 46.0 46  | Cyathura polita | 46 | 46.0 46  | Carinoma tremaphoros | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 1725 |  | Total Abundance (w/o Epifauna) | 1725 |  | Number of Taxa | 9 |  | Number of Taxa (w/o Epifauna) | 9 |  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter) -  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Heteromastus filiformis | 0.1610 | 0.1610 0.1610 0.1 | Marenzelleria viridis | 0.0391 | 0.0391 0.0391 0.0 | Rangia cuneata | 0.0368 | 0.0368 0.0368 0.0 | Cyathura polita | 0.0345 | 0.0345 0.0345 0.0 | Streblospio benedicti | 0.0161 | 0.0161 0.0161 0.0 | Edwardsia elegans | 0.0069 | 0.0069 0.0069 0.0 | Leptocheirus plumulosus | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Carinoma tremaphoros | 0.0023 | 0.0023 0.0023 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 0.3082 |  | Total Biomass (w/o Epifauna) | 0.3082 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: SC-04-XX  | Location: Habitat: Low Mesohaline Date: June 30, 2000  | Gear: Modified Box Corer Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.51 Pollution Indicative Species Abundance (%) 20 | Abundance (#/m2) 14800 Pollution Indicative Species Biomass (%)  | Biomass (g/m2) 6.46 Pollution Sensitive Species Abundance (%) 17 | Carnivore-Omnivore Abundance (%) 10.54 Pollution Sensitive Species Biomass (%)  | Deep Deposit Feeder Abundance (%) 53.51  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Heteromastus filiformis | 7480 | 7480.0 7480 74 | Streblospio benedicti | 2560 | 2560.0 2560 25 | Marenzelleria viridis | 1400 | 1400.0 1400 14 | Cyathura polita | 520 | 520.0 520 5 | Leptocheirus plumulosus | 480 | 480.0 480 4 | Rangia cuneata | 480 | 480.0 480 4 | Carinoma tremaphoros | 400 | 400.0 400 4 | Hypereteone heteropoda | 280 | 280.0 280 2 | Tubificoides spp. | 240 | 240.0 240 2 | Imm. Tubificid w/o Cap. Chaete | 200 | 200.0 200 2 --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC ABUNDANCE (per sq. meter) - Contd.  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Neanthes succinea | 200 | 200.0 200 2 | Macoma mitchelli | 200 | 200.0 200 2 | Edwardsia elegans | 160 | 160.0 160 1 | Macoma balthica | 120 | 120.0 120 1 | Hobsonia florida | 80 | 80.0 80  --------------------------------------------------------------------------------------------------------- | Total Abundance | 14800 |  | Total Abundance (w/o Epifauna) | 14800 |  | Number of Taxa | 15 |  | Number of Taxa (w/o Epifauna) | 15 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter) -  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Heteromastus filiformis | 2.2960 | 2.2960 2.2960 2.2 | Marenzelleria viridis | 1.1480 | 1.1480 1.1480 1.1 | Macoma mitchelli | 0.8160 | 0.8160 0.8160 0.8 | Rangia cuneata | 0.7320 | 0.7320 0.7320 0.7 | Macoma balthica | 0.5440 | 0.5440 0.5440 0.5 | Cyathura polita | 0.3120 | 0.3120 0.3120 0.3 | Neanthes succinea | 0.2880 | 0.2880 0.2880 0.2 | Carinoma tremaphoros | 0.0960 | 0.0960 0.0960 0.0 | Hypereteone heteropoda | 0.0880 | 0.0880 0.0880 0.0 | Streblospio benedicti | 0.0640 | 0.0640 0.0640 0.0 | Leptocheirus plumulosus | 0.0520 | 0.0520 0.0520 0.0 | Edwardsia elegans | 0.0160 | 0.0160 0.0160 0.0 | Hobsonia florida | 0.0040 | 0.0040 0.0040 0.0 | Tubificoides spp. | 0.0020 | 0.0020 0.0020 0.0 | Oligochaeta | 0.0020 | 0.0020 0.0020 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 6.4600 |  | Total Biomass (w/o Epifauna) | 6.4600 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: SC-05  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.4 Salinity (ppt): 4.9 Temperature (C): 2 | Dissolved Oxygen (mg/l): 7.71 Sediment Silt-Clay (%): 66.05 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 1.34 Pollution Indicative Species Abundance (%) 80 | Abundance (#/m2) 4968 Pollution Indicative Species Biomass (%) 29 | Biomass (g/m2) 0.69 Pollution Sensitive Species Abundance (%) 2 | Carnivore-Omnivore Abundance (%) 7.41 Pollution Sensitive Species Biomass (%) 47 | Deep Deposit Feeder Abundance (%) 4.63  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 3933 | 3933.0 3933 39 | Hobsonia florida | 391 | 391.0 391 3 | Heteromastus filiformis | 138 | 138.0 138 1 | Tubificoides spp. | 92 | 92.0 92  | Cyathura polita | 92 | 92.0 92  | Procladius spp. | 92 | 92.0 92  | Chironomus spp. | 69 | 69.0 69  | Edwardsia elegans | 46 | 46.0 46  | Carinoma tremaphoros | 46 | 46.0 46  | Edotea triloba (Epi) | 46 | 46.0 46  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC ABUNDANCE (per sq. meter) - Contd.  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Laeonereis culveri | 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  | Rangia cuneata | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 5014 |  | Total Abundance (w/o Epifauna) | 4968 |  | Number of Taxa | 13 |  | Number of Taxa (w/o Epifauna) | 12 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter) -  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Cyathura polita | 0.2576 | 0.2576 0.2576 0.2 | Streblospio benedicti | 0.2047 | 0.2047 0.2047 0.2 | Heteromastus filiformis | 0.0828 | 0.0828 0.0828 0.0 | Rangia cuneata | 0.0644 | 0.0644 0.0644 0.0 | Hobsonia florida | 0.0345 | 0.0345 0.0345 0.0 | Carinoma tremaphoros | 0.0299 | 0.0299 0.0299 0.0 | Edwardsia elegans | 0.0069 | 0.0069 0.0069 0.0 | Edotea triloba (Epi) | 0.0069 | 0.0069 0.0069 0.0 | Marenzelleria viridis | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Laeonereis culveri | 0.0023 | 0.0023 0.0023 0.0 | Chironomidae larvae | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 0.7004 |  | Total Biomass (w/o Epifauna) | 0.6935 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: SC-06  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.3 Salinity (ppt): 6.1 Temperature (C): 2 | Dissolved Oxygen (mg/l): 4.32 Sediment Silt-Clay (%): 97.81 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.49 Pollution Indicative Species Abundance (%) 16 | Abundance (#/m2) 713 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 2.62 Pollution Sensitive Species Abundance (%) 48 | Carnivore-Omnivore Abundance (%) 12.90 Pollution Sensitive Species Biomass (%) 99 | Deep Deposit Feeder Abundance (%) 35.48  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 253 | 253.0 253 2 | Macoma balthica | 138 | 138.0 138 1 | Marenzelleria viridis | 92 | 92.0 92  | Streblospio benedicti | 92 | 92.0 92  | Cyathura polita | 69 | 69.0 69  | Rangia cuneata | 46 | 46.0 46  | Littoridinops tenuipes (Epi) | 23 | 23.0 23  | Hypereteone heteropoda | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 736 |  | Total Abundance (w/o Epifauna) | 713 |  | Number of Taxa | 8 |  | Number of Taxa (w/o Epifauna) | 7 |  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 2.3230 | 2.3230 2.3230 2.3 | Marenzelleria viridis | 0.1426 | 0.1426 0.1426 0.1 | Cyathura polita | 0.1150 | 0.1150 0.1150 0.1 | Rangia cuneata | 0.0184 | 0.0184 0.0184 0.0 | Tubificoides spp. | 0.0092 | 0.0092 0.0092 0.0 | Streblospio benedicti | 0.0092 | 0.0092 0.0092 0.0 | Littoridinops tenuipes (Epi) | 0.0069 | 0.0069 0.0069 0.0 | Hypereteone heteropoda | 0.0023 | 0.0023 0.0023 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 2.6266 |  | Total Biomass (w/o Epifauna) | 2.6197 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: SC-07  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.0 Salinity (ppt): 5.2 Temperature (C):  | Dissolved Oxygen (mg/l): 8.73 Sediment Silt-Clay (%): 88.94 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 1.58 Pollution Indicative Species Abundance (%) 73 | Abundance (#/m2) 9982 Pollution Indicative Species Biomass (%) 20 | Biomass (g/m2) 1.15 Pollution Sensitive Species Abundance (%) 2 | Carnivore-Omnivore Abundance (%) 11.52 Pollution Sensitive Species Biomass (%) 42 | Deep Deposit Feeder Abundance (%) 3.23  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 7153 | 7153.0 7153 71 | Hobsonia florida | 1219 | 1219.0 1219 12 | Edwardsia elegans | 667 | 667.0 667 6 | Tubificoides spp. | 253 | 253.0 253 2 | Carinoma tremaphoros | 184 | 184.0 184 1 | Tanypus neopunctipennis | 138 | 138.0 138 1 | Cyathura polita | 92 | 92.0 92  | Heteromastus filiformis | 69 | 69.0 69  | Chironomus spp. | 46 | 46.0 46  | Marenzelleria viridis | 46 | 46.0 46  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC ABUNDANCE (per sq. meter) - Contd.  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 46 | 46.0 46  | Rangia cuneata | 46 | 46.0 46  | Neanthes succinea | 23 | 23.0 23  | Edotea triloba (Epi) | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Total Abundance | 10005 |  | Total Abundance (w/o Epifauna) | 9982 |  | Number of Taxa | 14 |  | Number of Taxa (w/o Epifauna) | 13 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter) -  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 0.2898 | 0.2898 0.2898 0.2 | Streblospio benedicti | 0.2392 | 0.2392 0.2392 0.2 | Marenzelleria viridis | 0.1817 | 0.1817 0.1817 0.1 | Carinoma tremaphoros | 0.1656 | 0.1656 0.1656 0.1 | Edwardsia elegans | 0.1403 | 0.1403 0.1403 0.1 | Heteromastus filiformis | 0.0644 | 0.0644 0.0644 0.0 | Hobsonia florida | 0.0391 | 0.0391 0.0391 0.0 | Edotea triloba (Epi) | 0.0322 | 0.0322 0.0322 0.0 | Rangia cuneata | 0.0184 | 0.0184 0.0184 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Neanthes succinea | 0.0023 | 0.0023 0.0023 0.0 | Cyathura polita | 0.0023 | 0.0023 0.0023 0.0 | Chironomidae larvae | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.1811 |  | Total Biomass (w/o Epifauna) | 1.1420 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: SC-08  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.3 Salinity (ppt): 5.7 Temperature (C): 2 | Dissolved Oxygen (mg/l): 4.59 Sediment Silt-Clay (%): 93.75 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.87 Pollution Indicative Species Abundance (%) 13 | Abundance (#/m2) 345 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 1.65 Pollution Sensitive Species Abundance (%) 60 | Carnivore-Omnivore Abundance (%) 26.67 Pollution Sensitive Species Biomass (%) 43 | Deep Deposit Feeder Abundance (%) 6.67  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Cyathura polita | 69 | 69.0 69  | Macoma balthica | 69 | 69.0 69  | Marenzelleria viridis | 46 | 46.0 46  | Streblospio benedicti | 46 | 46.0 46  | Macoma mitchelli | 46 | 46.0 46  | Carinoma tremaphoros | 23 | 23.0 23  | Heteromastus filiformis | 23 | 23.0 23  | Rangia cuneata | 23 | 23.0 23  -------------------------------------------------------------------------------------------------------- | Total Abundance | 345 |  | Total Abundance (w/o Epifauna) | 345 |  | Number of Taxa | 8 |  | Number of Taxa (w/o Epifauna) | 8 |  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma mitchelli | 0.6279 | 0.6279 0.6279 0.6 | Macoma balthica | 0.4646 | 0.4646 0.4646 0.4 | Heteromastus filiformis | 0.2760 | 0.2760 0.2760 0.2 | Marenzelleria viridis | 0.1748 | 0.1748 0.1748 0.1 | Cyathura polita | 0.0644 | 0.0644 0.0644 0.0 | Carinoma tremaphoros | 0.0299 | 0.0299 0.0299 0.0 | Rangia cuneata | 0.0115 | 0.0115 0.0115 0.0 | Streblospio benedicti | 0.0046 | 0.0046 0.0046 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.6537 |  | Total Biomass (w/o Epifauna) | 1.6537 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: SC-09  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.1 Salinity (ppt): 6.1 Temperature (C): 2 | Dissolved Oxygen (mg/l): 4.02 Sediment Silt-Clay (%): 99.35 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.71 Pollution Indicative Species Abundance (%) 17 | Abundance (#/m2) 644 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 3.17 Pollution Sensitive Species Abundance (%) 53 | Carnivore-Omnivore Abundance (%) 32.14 Pollution Sensitive Species Biomass (%) 79 | Deep Deposit Feeder Abundance (%) 14.29  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 161 | 161.0 161 1 | Cyathura polita | 138 | 138.0 138 1 | Streblospio benedicti | 115 | 115.0 115 1 | Tubificoides spp. | 92 | 92.0 92  | Carinoma tremaphoros | 46 | 46.0 46  | Rangia cuneata | 46 | 46.0 46  | Rhithropanopeus harrisi (Epi)| 23 | 23.0 23  | Neanthes succinea | 23 | 23.0 23  | Leptocheirus plumulosus | 23 | 23.0 23  -------------------------------------------------------------------------------------------------------- | Total Abundance | 667 |  | Total Abundance (w/o Epifauna) | 644 |  | Number of Taxa | 9 |  | Number of Taxa (w/o Epifauna) | 8 |  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 2.4495 | 2.4495 2.4495 2.4 | Neanthes succinea | 0.5911 | 0.5911 0.5911 0.5 | Cyathura polita | 0.0437 | 0.0437 0.0437 0.0 | Carinoma tremaphoros | 0.0322 | 0.0322 0.0322 0.0 | Rangia cuneata | 0.0322 | 0.0322 0.0322 0.0 | Leptocheirus plumulosus | 0.0138 | 0.0138 0.0138 0.0 | Streblospio benedicti | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Rhithropanopeus harrisi (Epi)| 0.0046 | 0.0046 0.0046 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 3.1786 |  | Total Biomass (w/o Epifauna) | 3.1740 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 ========================================================================================================= | Station: SC-10  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: June 30, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.0 Salinity (ppt): 5.9 Temperature (C): 2 | Dissolved Oxygen (mg/l): 4.84 Sediment Silt-Clay (%): 96.98 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: Condition: Not Applicable # Attributes Score | Value Score Va | Shannon-Weiner Index 2.29 Pollution Indicative Species Abundance (%) 35 | Abundance (#/m2) 644 Pollution Indicative Species Biomass (%) 11 | Biomass (g/m2) 0.18 Pollution Sensitive Species Abundance (%) 28 | Carnivore-Omnivore Abundance (%) 7.14 Pollution Sensitive Species Biomass (%) 83 | Deep Deposit Feeder Abundance (%) 32.14  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 230 | 230.0 230 2 | Tubificoides spp. | 207 | 207.0 207 2 | Rangia cuneata | 69 | 69.0 69  | Marenzelleria viridis | 46 | 46.0 46  | Cyathura polita | 46 | 46.0 46  | Littoridinops tenuipes (Epi) | 23 | 23.0 23  | Ameroculodes species complex | 23 | 23.0 23  | Macoma balthica | 23 | 23.0 23  -------------------------------------------------------------------------------------------------------- | Total Abundance | 667 |  | Total Abundance (w/o Epifauna) | 644 |  | Number of Taxa | 8 |  | Number of Taxa (w/o Epifauna) | 7 |  --------------------------------------------------------------------------------------------------------- Co
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SPRING 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 0.0552 | 0.0552 0.0552 0.0 | Marenzelleria viridis | 0.0552 | 0.0552 0.0552 0.0 | Rangia cuneata | 0.0253 | 0.0253 0.0253 0.0 | Streblospio benedicti | 0.0207 | 0.0207 0.0207 0.0 | Cyathura polita | 0.0161 | 0.0161 0.0161 0.0 | Ameroculodes species complex | 0.0069 | 0.0069 0.0069 0.0 | Littoridinops tenuipes (Epi) | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 0.1886 |  | Total Biomass (w/o Epifauna) | 0.1817 |  ---------------------------------------------------------------------------------------------------------
Appendix B

APPENDIX B

BOTTOM ENVIRONMENT AND

BENTHOS SUMMER
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: HC-03  | Location: Hunting Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.9 Salinity (ppt): 6.92 Temperature (C): 2 | Dissolved Oxygen (mg/l): 6.9 Sediment Silt-Clay (%): 95.85 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 2.60 Condition: Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 1.42 1 Pollution Indicative Species Abundance (%) 0 | Abundance (#/m2) 276 1 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 4.54 3 Pollution Sensitive Species Abundance (%) 75 | Carnivore-Omnivore Abundance (%) 25.00 Pollution Sensitive Species Biomass (%) 97 | Deep Deposit Feeder Abundance (%) 8.33  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 184 | 184.0 184 1 | Carinoma tremaphoros | 46 | 46.0 46  | Heteromastus filiformis | 23 | 23.0 23  | Cyathura polita | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 4 |  | Number of Species (w/o Epifauna) | 4 |  | Abundance | 276 |  | Abundance (w/o Epifauna) | 276 |  |--------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  |-------------------------------------------------------------------------------------------------------- | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 4.3401 | 4.3401 4.3401 4.3 | Cyathura polita | 0.1035 | 0.1035 0.1035 0.1 | Heteromastus filiformis | 0.0621 | 0.0621 0.0621 0.0 | Carinoma tremaphoros | 0.0391 | 0.0391 0.0391 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 4.5448 |  | Biomass (w/o Epifauna) | 4.5448 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: HC-04  | Location: Hunting Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.4 Salinity (ppt): 7.23 Temperature (C): 2 | Dissolved Oxygen (mg/l): 6.5 Sediment Silt-Clay (%): 82.07 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.00 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 1.87 3 Pollution Indicative Species Abundance (%) 48 | Abundance (#/m2) 897 3 Pollution Indicative Species Biomass (%) 5 | Biomass (g/m2) 1.55 3 Pollution Sensitive Species Abundance (%) 15 | Carnivore-Omnivore Abundance (%) 56.41 Pollution Sensitive Species Biomass (%) 86 | Deep Deposit Feeder Abundance (%) 2.56  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Coelotanypus spp. | 414 | 414.0 414 4 | Leptocheirus plumulosus | 299 | 299.0 299 2 | Melita nitida (Epi) | 161 | 161.0 161 1 | Cyathura polita | 92 | 92.0 92  | Macoma balthica | 46 | 46.0 46  | Tubificoides spp. | 23 | 23.0 23  | Streblospio benedicti | 23 | 23.0 23  |-------------------------------------------------------------------------------------------------------- | Number of Species | 7 |  | Number of Species (w/o Epifauna) | 6 |  | Abundance | 1058 |  | Abundance (w/o Epifauna) | 897 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 0.9108 | 0.9108 0.9108 0.9 | Cyathura polita | 0.4347 | 0.4347 0.4347 0.4 | Leptocheirus plumulosus | 0.1219 | 0.1219 0.1219 0.1 | Coelotanypus spp. | 0.0782 | 0.0782 0.0782 0.0 | Melita nitida (Epi) | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.5721 |  | Biomass (w/o Epifauna) | 1.5652 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: HC-05  | Location: Hunting Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 2.0 Salinity (ppt): 5.67 Temperature (C): 2 | Dissolved Oxygen (mg/l): 8.5 Sediment Silt-Clay (%): 40.62 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 2.60 Condition: Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 2.32 3 Pollution Indicative Species Abundance (%) 20 | Abundance (#/m2) 1794 5 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 0.71 1 Pollution Sensitive Species Abundance (%) 8 | Carnivore-Omnivore Abundance (%) 15.38 Pollution Sensitive Species Biomass (%) 64 | Deep Deposit Feeder Abundance (%) 53.85  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 828 | 828.0 828 8 | Streblospio benedicti | 368 | 368.0 368 3 | Carinoma tremaphoros | 184 | 184.0 184 1 | Heteromastus filiformis | 138 | 138.0 138 1 | Leptocheirus plumulosus | 115 | 115.0 115 1 | Cyathura polita | 92 | 92.0 92  | Rhithropanopeus harrisi (Epi)| 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  | Macoma balthica | 23 | 23.0 23  | Rangia cuneata | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 10 |  | Number of Species (w/o Epifauna) | 9 |  | Abundance | 1817 |  | Abundance (w/o Epifauna) | 1794 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Rangia cuneata | 0.1794 | 0.1794 0.1794 0.1 | Cyathura polita | 0.1495 | 0.1495 0.1495 0.1 | Carinoma tremaphoros | 0.1081 | 0.1081 0.1081 0.1 | Marenzelleria viridis | 0.1058 | 0.1058 0.1058 0.1 | Heteromastus filiformis | 0.0966 | 0.0966 0.0966 0.0 | Rhithropanopeus harrisi (Epi)| 0.0713 | 0.0713 0.0713 0.0 | Leptocheirus plumulosus | 0.0414 | 0.0414 0.0414 0.0 | Macoma balthica | 0.0230 | 0.0230 0.0230 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Streblospio benedicti | 0.0023 | 0.0023 0.0023 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 0.7797 |  | Biomass (w/o Epifauna) | 0.7084 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: HC-06  | Location: Hunting Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.3 Salinity (ppt): 6.60 Temperature (C): 2 | Dissolved Oxygen (mg/l): 6.7 Sediment Silt-Clay (%): 96.92 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 4.60 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.69 5 Pollution Indicative Species Abundance (%) 9 | Abundance (#/m2) 2783 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 5.56 5 Pollution Sensitive Species Abundance (%) 24 | Carnivore-Omnivore Abundance (%) 14.05 Pollution Sensitive Species Biomass (%) 91 | Deep Deposit Feeder Abundance (%) 31.40  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 943 | 943.0 943 9 | Macoma balthica | 529 | 529.0 529 5 | Tubificoides spp. | 437 | 437.0 437 4 | Imm. Tubificid w/o Cap. Chaete | 230 | 230.0 230 2 | Heteromastus filiformis | 207 | 207.0 207 2 | Carinoma tremaphoros | 184 | 184.0 184 1 | Cyathura polita | 161 | 161.0 161 1 | Neanthes succinea | 46 | 46.0 46  | Streblospio benedicti | 23 | 23.0 23  | Melita nitida (Epi) | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  |--------------------------------------------------------------------------------------------------------

 | Number of Species | 11 | 

 | Number of Species (w/o Epifauna) | 10 |  | Abundance | 2806 |  | Abundance (w/o Epifauna) | 2783 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000 

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  |-------------------------------------------------------------------------------------------------------- | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 4.8806 | 4.8806 4.8806 4.8 | Leptocheirus plumulosus | 0.2852 | 0.2852 0.2852 0.2 | Cyathura polita | 0.1817 | 0.1817 0.1817 0.1 | Macoma mitchelli | 0.1541 | 0.1541 0.1541 0.1 | Neanthes succinea | 0.0230 | 0.0230 0.0230 0.0 | Heteromastus filiformis | 0.0184 | 0.0184 0.0184 0.0 | Tubificoides spp. | 0.0115 | 0.0115 0.0115 0.0 | Carinoma tremaphoros | 0.0023 | 0.0023 0.0023 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Melita nitida (Epi) | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 5.5603 |  | Biomass (w/o Epifauna) | 5.5491 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: HC-09  | Location: Hunting Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.8 Salinity (ppt): 5.89 Temperature (C): 2 | Dissolved Oxygen (mg/l): 8.9 Sediment Silt-Clay (%): 91.77 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.00 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 1.37 1 Pollution Indicative Species Abundance (%) 6 | Abundance (#/m2) 1035 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 0.24 1 Pollution Sensitive Species Abundance (%) 8 | Carnivore-Omnivore Abundance (%) 8.89 Pollution Sensitive Species Biomass (%) 85 | Deep Deposit Feeder Abundance (%) 82.22  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 805 | 805.0 805 8 | Limnodrilus hoffmeisteri | 46 | 46.0 46  | Leptocheirus plumulosus | 46 | 46.0 46  | Cyathura polita | 46 | 46.0 46  | Carinoma tremaphoros | 23 | 23.0 23  | Coelotanypus spp. | 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  | Melita nitida (Epi) | 23 | 23.0 23  | Macoma balthica | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 9 |  | Number of Species (w/o Epifauna) | 8 |  | Abundance | 1058 |  | Abundance (w/o Epifauna) | 1035 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter) -  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Cyathura polita | 0.1012 | 0.1012 0.1012 0.1 | Macoma balthica | 0.0989 | 0.0989 0.0989 0.0 | Leptocheirus plumulosus | 0.0207 | 0.0207 0.0207 0.0 | Carinoma tremaphoros | 0.0115 | 0.0115 0.0115 0.0 | Marenzelleria viridis | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Coelotanypus spp. | 0.0012 | 0.0012 0.0012 0.0 | Melita nitida (Epi) | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 0.2438 |  | Biomass (w/o Epifauna) | 0.2426 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: HC-11  | Location: Hunting Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.4 Salinity (ppt): 6.24 Temperature (C): 1 | Dissolved Oxygen (mg/l): 5.0 Sediment Silt-Clay (%): 98.42 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.40 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.34 3 Pollution Indicative Species Abundance (%) 16 | Abundance (#/m2) 1288 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 4.90 3 Pollution Sensitive Species Abundance (%) 35 | Carnivore-Omnivore Abundance (%) 16.07 Pollution Sensitive Species Biomass (%) 98 | Deep Deposit Feeder Abundance (%) 48.21  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 483 | 483.0 483 4 | Macoma balthica | 391 | 391.0 391 3 | Imm. Tubificid w/o Cap. Chaete | 138 | 138.0 138 1 | Carinoma tremaphoros | 92 | 92.0 92  | Cyathura polita | 69 | 69.0 69  | Coelotanypus spp. | 46 | 46.0 46  | Leptocheirus plumulosus | 46 | 46.0 46  | Streblospio benedicti | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 8 |  | Number of Species (w/o Epifauna) | 8 |  | Abundance | 1288 |  | Abundance (w/o Epifauna) | 1288 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter) - Contd.  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M ========================================================================================================= | Macoma balthica | 4.5287 | 4.5287 4.5287 4.5 | Cyathura polita | 0.3082 | 0.3082 0.3082 0.3 | Carinoma tremaphoros | 0.0345 | 0.0345 0.0345 0.0 | Leptocheirus plumulosus | 0.0161 | 0.0161 0.0161 0.0 | Coelotanypus spp. | 0.0092 | 0.0092 0.0092 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 4.9013 |  | Biomass (w/o Epifauna) | 4.9013 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: HC-12  | Location: Hunting Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.4 Salinity (ppt): 5.99 Temperature (C): 18 | Dissolved Oxygen (mg/l): 5.4 Sediment Silt-Clay (%): 99.25 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 4.60 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 1.77 3 Pollution Indicative Species Abundance (%) 7 | Abundance (#/m2) 2024 5 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 5.11 5 Pollution Sensitive Species Abundance (%) 13 | Carnivore-Omnivore Abundance (%) 9.09 Pollution Sensitive Species Biomass (%) 89 | Deep Deposit Feeder Abundance (%) 73.86  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 1334 | 1334.0 1334 13 | Macoma balthica | 253 | 253.0 253 2 | Carinoma tremaphoros | 138 | 138.0 138 1 | Imm. Tubificid w/o Cap. Chaete | 138 | 138.0 138 1 | Leptocheirus plumulosus | 46 | 46.0 46  | Macoma mitchelli | 46 | 46.0 46  | Coelotanypus spp. | 23 | 23.0 23  | Heteromastus filiformis | 23 | 23.0 23  | Cyathura polita | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 9 |  | Number of Species (w/o Epifauna) | 9 |  | Abundance | 2024 |  | Abundance (w/o Epifauna) | 2024 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter) - Contd.  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 4.3654 | 4.3654 4.3654 4.3 | Macoma mitchelli | 0.4439 | 0.4439 0.4439 0.4 | Cyathura polita | 0.1955 | 0.1955 0.1955 0.1 | Carinoma tremaphoros | 0.0759 | 0.0759 0.0759 0.0 | Tubificoides spp. | 0.0184 | 0.0184 0.0184 0.0 | Coelotanypus spp. | 0.0092 | 0.0092 0.0092 0.0 | Leptocheirus plumulosus | 0.0023 | 0.0023 0.0023 0.0 | Heteromastus filiformis | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 5.1129 |  | Biomass (w/o Epifauna) | 5.1129 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: HC-13  | Location: Hunting Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.9 Salinity (ppt): 6.12 Temperature (C): 1 | Dissolved Oxygen (mg/l): 4.4 Sediment Silt-Clay (%): 2.05 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.00 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.62 5 Pollution Indicative Species Abundance (%) 44 | Abundance (#/m2) 2599 3 Pollution Indicative Species Biomass (%) 2 | Biomass (g/m2) 1.47 3 Pollution Sensitive Species Abundance (%) 11 | Carnivore-Omnivore Abundance (%) 33.63 Pollution Sensitive Species Biomass (%) 76 | Deep Deposit Feeder Abundance (%) 11.50  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 1012 | 1012.0 1012 10 | Laeonereis culveri | 621 | 621.0 621 6 | Heteromastus filiformis | 276 | 276.0 276 2 | Rangia cuneata | 161 | 161.0 161 1 | Hypereteone heteropoda | 138 | 138.0 138 1 | Leptocheirus plumulosus | 138 | 138.0 138 1 | Marenzelleria viridis | 92 | 92.0 92  | Carinoma tremaphoros | 46 | 46.0 46  | Cyathura polita | 46 | 46.0 46  | Tubificoides spp. | 23 | 23.0 23  | Neanthes succinea | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  | Apocorophium lacustre (Epi) | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 --------------------------------------------------------------------------------------------------------- | Number of Species | 13 |  | Number of Species (w/o Epifauna) | 12 |  | Abundance | 2622 |  | Abundance (w/o Epifauna) | 2599 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  --------------------------------------------------------------------------------------------------------- | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Rangia cuneata | 1.0350 | 1.0350 1.0350 1.0 | Laeonereis culveri | 0.1196 | 0.1196 0.1196 0.1 | Macoma mitchelli | 0.0874 | 0.0874 0.0874 0.0 | Heteromastus filiformis | 0.0736 | 0.0736 0.0736 0.0 | Marenzelleria viridis | 0.0575 | 0.0575 0.0575 0.0 | Cyathura polita | 0.0345 | 0.0345 0.0345 0.0 | Streblospio benedicti | 0.0230 | 0.0230 0.0230 0.0 | Leptocheirus plumulosus | 0.0161 | 0.0161 0.0161 0.0 | Hypereteone heteropoda | 0.0138 | 0.0138 0.0138 0.0 | Carinoma tremaphoros | 0.0092 | 0.0092 0.0092 0.0 | Neanthes succinea | 0.0023 | 0.0023 0.0023 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Apocorophium lacustre (Epi) | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 1.4743 |  | Biomass (w/o Epifauna) | 1.4711 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: HC-14  | Location: Hunting Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.4 Salinity (ppt): 6.57 Temperature (C): 1 | Dissolved Oxygen (mg/l): 4.0 Sediment Silt-Clay (%): 91.90 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 2.60 Condition: Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 2.28 3 Pollution Indicative Species Abundance (%) 12 | Abundance (#/m2) 368 1 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 1.94 3 Pollution Sensitive Species Abundance (%) 50 | Carnivore-Omnivore Abundance (%) 18.75 Pollution Sensitive Species Biomass (%) 99 | Deep Deposit Feeder Abundance (%) 25.00  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 138 | 138.0 138 1 | Tubificoides spp. | 92 | 92.0 92  | Leptocheirus plumulosus | 46 | 46.0 46  | Cyathura polita | 46 | 46.0 46  | Coelotanypus spp. | 23 | 23.0 23  | Streblospio benedicti | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 6 |  | Number of Species (w/o Epifauna) | 6 |  | Abundance | 368 |  | Abundance | 368 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 1.7641 | 1.7641 1.7641 1.7 | Cyathura polita | 0.1702 | 0.1702 0.1702 0.1 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Coelotanypus spp. | 0.0023 | 0.0023 0.0023 0.0 | Streblospio benedicti | 0.0023 | 0.0023 0.0023 0.0 | Leptocheirus plumulosus | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Total Biomass | 1.9445 |  | Biomass (w/o Epifauna) | 1.9445 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: HC-15  | Location: Hunting Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.4 Salinity (ppt): 6.63 Temperature (C): 1 | Dissolved Oxygen (mg/l): 4.4 Sediment Silt-Clay (%): 97.32 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 2.20 Condition: Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 2.23 3 Pollution Indicative Species Abundance (%) 40 | Abundance (#/m2) 460 1 Pollution Indicative Species Biomass (%) 1 | Biomass (g/m2) 1.64 3 Pollution Sensitive Species Abundance (%) 25 | Carnivore-Omnivore Abundance (%) 45.00 Pollution Sensitive Species Biomass (%) 97 | Deep Deposit Feeder Abundance (%) 35.00  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Coelotanypus spp. | 161 | 161.0 161 1 | Tubificoides spp. | 138 | 138.0 138 1 | Macoma balthica | 69 | 69.0 69  | Cyathura polita | 46 | 46.0 46  | Imm. Tubificid w/o Cap. Chaete | 23 | 23.0 23  | Leptocheirus plumulosus | 23 | 23.0 23  | Melita nitida (Epi) | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 7 |  | Number of Species (w/o Epifauna)| 6 |  | Abundance | 483 |  | Abundance (w/o Epifauna) | 460 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 1.3754 | 1.3754 1.3754 1.3 | Cyathura polita | 0.2300 | 0.2300 0.2300 0.2 | Coelotanypus spp. | 0.0184 | 0.0184 0.0184 0.0 | Leptocheirus plumulosus | 0.0161 | 0.0161 0.0161 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Melita nitida (Epi) | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 1.6445 |  | Biomass (w/o Epifauna) | 1.6433 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: PR-13  | Location: Patuxent River Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.2 Salinity (ppt): 8.84 Temperature (C): 1 | Dissolved Oxygen (mg/l): 4.4 Sediment Silt-Clay (%): 28.84 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 4.60 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 3.15 5 Pollution Indicative Species Abundance (%) 2 | Abundance (#/m2) 2139 5 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 4.97 3 Pollution Sensitive Species Abundance (%) 31 | Carnivore-Omnivore Abundance (%) 41.94 Pollution Sensitive Species Biomass (%) 82 | Deep Deposit Feeder Abundance (%) 20.43  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Carinoma tremaphoros | 483 | 483.0 483 4 | Leptocheirus plumulosus | 345 | 345.0 345 3 | Macoma balthica | 299 | 299.0 299 2 | Cyathura polita | 276 | 276.0 276 2 | Heteromastus filiformis | 207 | 207.0 207 2 | Tubificoides spp. | 184 | 184.0 184 1 | Macoma mitchelli | 115 | 115.0 115 1 | Neanthes succinea | 69 | 69.0 69  | Imm. Tubificid w/o Cap. Chaete | 46 | 46.0 46  | Glycinde solitaria | 46 | 46.0 46  | Podarkeopsis levifuscina | 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  | Rangia cuneata | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 --------------------------------------------------------------------------------------------------------- | Number of Species | 13 |  | Number of Species (w/o Epifauna)| 13 |  | Abundance | 2139 |  | Abundance (w/o Epifauna) | 2139 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  --------------------------------------------------------------------------------------------------------- | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 3.1970 | 3.1970 3.1970 3.1 | Cyathura polita | 0.5336 | 0.5336 0.5336 0.5 | Macoma mitchelli | 0.5037 | 0.5037 0.5037 0.5 | Rangia cuneata | 0.3634 | 0.3634 0.3634 0.3 | Heteromastus filiformis | 0.1472 | 0.1472 0.1472 0.1 | Carinoma tremaphoros | 0.0920 | 0.0920 0.0920 0.0 | Leptocheirus plumulosus | 0.0713 | 0.0713 0.0713 0.0 | Neanthes succinea | 0.0322 | 0.0322 0.0322 0.0 | Marenzelleria viridis | 0.0230 | 0.0230 0.0230 0.0 | Glycinde solitaria | 0.0023 | 0.0023 0.0023 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Podarkeopsis levifuscina | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 4.6969 |  | Biomass | 4.6969 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: PR-14  | Location: Patuxent River Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 2.1 Salinity (ppt): 7.70 Temperature (C): 1 | Dissolved Oxygen (mg/l): 3.7 Sediment Silt-Clay (%): 66.23 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 4.20 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 3.17 5 Pollution Indicative Species Abundance (%) 35 | Abundance (#/m2) 1679 5 Pollution Indicative Species Biomass (%) 1 | Biomass (g/m2) 5.64 5 Pollution Sensitive Species Abundance (%) 28 | Carnivore-Omnivore Abundance (%) 34.25 Pollution Sensitive Species Biomass (%) 85 | Deep Deposit Feeder Abundance (%) 21.92  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Coelotanypus spp. | 345 | 345.0 345 3 | Macoma balthica | 322 | 322.0 322 3 | Leptocheirus plumulosus | 230 | 230.0 230 2 | Imm. Tubificid w/o Cap. Chaete | 207 | 207.0 207 2 | Cyathura polita | 138 | 138.0 138 1 | Tubificoides spp. | 115 | 115.0 115 1 | Macoma mitchelli | 115 | 115.0 115 1 | Carinoma tremaphoros | 46 | 46.0 46  | Heteromastus filiformis | 46 | 46.0 46  | Neanthes succinea | 46 | 46.0 46  | Streblospio benedicti | 46 | 46.0 46  | Marenzelleria viridis | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 12 |  | Number of Species (w/o Epifauna) | 12 |  | Abundance | 1679 |  | Abundance (w/o Epifauna) | 1679 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  --------------------------------------------------------------------------------------------------------- | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 4.3999 | 4.3999 4.3999 4.3 | Macoma mitchelli | 0.3657 | 0.3657 0.3657 0.3 | Cyathura polita | 0.3220 | 0.3220 0.3220 0.3 | Neanthes succinea | 0.2783 | 0.2783 0.2783 0.2 | Coelotanypus spp. | 0.0805 | 0.0805 0.0805 0.0 | Marenzelleria viridis | 0.0805 | 0.0805 0.0805 0.0 | Heteromastus filiformis | 0.0575 | 0.0575 0.0575 0.0 | Leptocheirus plumulosus | 0.0529 | 0.0529 0.0529 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Carinoma tremaphoros | 0.0012 | 0.0012 0.0012 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 5.6431 |  | Biomass (w/o Epifauna) | 5.6431 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: PR-15  | Location: Patuxent River Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 5.5 Salinity (ppt): 8.86 Temperature (C): 1 | Dissolved Oxygen (mg/l): 3.6 Sediment Silt-Clay (%): 95.43 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 4.60 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.56 5 Pollution Indicative Species Abundance (%) 3 | Abundance (#/m2) 3197 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 9.52 5 Pollution Sensitive Species Abundance (%) 18 | Carnivore-Omnivore Abundance (%) 16.55 Pollution Sensitive Species Biomass (%) 87 | Deep Deposit Feeder Abundance (%) 18.71  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 1403 | 1403.0 1403 14 | Tubificoides spp. | 506 | 506.0 506 5 | Macoma balthica | 483 | 483.0 483 4 | Carinoma tremaphoros | 299 | 299.0 299 2 | Neanthes succinea | 115 | 115.0 115 1 | Cyathura polita | 92 | 92.0 92  | Macoma mitchelli | 92 | 92.0 92  | Imm. Tubificid w/o Cap. Chaete | 46 | 46.0 46  | Heteromastus filiformis | 46 | 46.0 46  | Streblospio benedicti | 46 | 46.0 46  | Coelotanypus spp. | 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  | Melita nitida (Epi) | 23 | 23.0 23  | Leucon americanus | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 --------------------------------------------------------------------------------------------------------- | Number of Species | 14 |  | Number of Species (w/o Epifauna) | 13 |  | Abundance | 3220 |  | Abundance (w/o Epifauna) | 3197 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  --------------------------------------------------------------------------------------------------------- | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 8.1029 | 8.1029 8.1029 8.1 | Neanthes succinea | 0.3634 | 0.3634 0.3634 0.3 | Macoma mitchelli | 0.3404 | 0.3404 0.3404 0.3 | Leptocheirus plumulosus | 0.2530 | 0.2530 0.2530 0.2 | Cyathura polita | 0.2093 | 0.2093 0.2093 0.2 | Heteromastus filiformis | 0.1288 | 0.1288 0.1288 0.1 | Carinoma tremaphoros | 0.0759 | 0.0759 0.0759 0.0 | Marenzelleria viridis | 0.0207 | 0.0207 0.0207 0.0 | Tubificoides spp. | 0.0069 | 0.0069 0.0069 0.0 | Coelotanypus spp. | 0.0069 | 0.0069 0.0069 0.0 | Leucon americanus | 0.0046 | 0.0046 0.0046 0.0 | Streblospio benedicti | 0.0023 | 0.0023 0.0023 0.0 | Melita nitida (Epi) | 0.0023 | 0.0023 0.0023 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 9.5185 |  | Biomass (w/o Epifauna) | 9.5162 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: PR-16  | Location: Patuxent River Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.5 Salinity (ppt): 6.86 Temperature (C): 2 | Dissolved Oxygen (mg/l): 5.6 Sediment Silt-Clay (%): 88.90 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 5.00 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.64 5 Pollution Indicative Species Abundance (%) 7 | Abundance (#/m2) 2323 5 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 6.59 5 Pollution Sensitive Species Abundance (%) 32 | Carnivore-Omnivore Abundance (%) 13.86 Pollution Sensitive Species Biomass (%) 97 | Deep Deposit Feeder Abundance (%) 47.52  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 759 | 759.0 759 7 | Macoma balthica | 644 | 644.0 644 6 | Carinoma tremaphoros | 184 | 184.0 184 1 | Heteromastus filiformis | 184 | 184.0 184 1 | Leptocheirus plumulosus | 184 | 184.0 184 1 | Imm. Tubificid w/o Cap. Chaete | 161 | 161.0 161 1 | Cyathura polita | 115 | 115.0 115 1 | Macoma mitchelli | 46 | 46.0 46  | Neanthes succinea | 23 | 23.0 23  | Streblospio benedicti | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 10 |  | Number of Species (w/o Epifauna) | 10 |  | Abundance | 2323 |  | Abundance (w/o Epifauna) | 2323 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 6.0835 | 6.0835 6.0835 6.0 | Cyathura polita | 0.3588 | 0.3588 0.3588 0.3 | Carinoma tremaphoros | 0.0621 | 0.0621 0.0621 0.0 | Heteromastus filiformis | 0.0483 | 0.0483 0.0483 0.0 | Macoma mitchelli | 0.0322 | 0.0322 0.0322 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Neanthes succinea | 0.0012 | 0.0012 0.0012 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Leptocheirus plumulosus | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 6.5906 |  | Biomass (w/o Epifauna) | 6.5906 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: PR-17  | Location: Patuxent River Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.5 Salinity (ppt): 7.94 Temperature (C): 1 | Dissolved Oxygen (mg/l): 3.8 Sediment Silt-Clay (%): 89.93 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 4.60 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.08 3 Pollution Indicative Species Abundance (%) 6 | Abundance (#/m2) 2392 5 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 6.46 5 Pollution Sensitive Species Abundance (%) 24 | Carnivore-Omnivore Abundance (%) 11.54 Pollution Sensitive Species Biomass (%) 94 | Deep Deposit Feeder Abundance (%) 62.50  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 1357 | 1357.0 1357 13 | Macoma balthica | 460 | 460.0 460 4 | Leptocheirus plumulosus | 138 | 138.0 138 1 | Cyathura polita | 115 | 115.0 115 1 | Imm. Tubificid w/o Cap. Chaete | 92 | 92.0 92  | Carinoma tremaphoros | 69 | 69.0 69  | Coelotanypus spp. | 69 | 69.0 69  | Heteromastus filiformis | 46 | 46.0 46  | Neanthes succinea | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 --------------------------------------------------------------------------------------------------------- | Number of Species | 10 |  | Number of Species (w/o Epifauna) | 10 |  | Abundance | 2392 |  | Abundance (w/o Epifauna) | 2392 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 5.6465 | 5.6465 5.6465 5.6 | Cyathura polita | 0.4278 | 0.4278 0.4278 0.4 | Macoma mitchelli | 0.2231 | 0.2231 0.2231 0.2 | Neanthes succinea | 0.0575 | 0.0575 0.0575 0.0 | Leptocheirus plumulosus | 0.0483 | 0.0483 0.0483 0.0 | Carinoma tremaphoros | 0.0299 | 0.0299 0.0299 0.0 | Coelotanypus spp. | 0.0115 | 0.0115 0.0115 0.0 | Heteromastus filiformis | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 6.4572 |  | Biomass (w/o Epifauna) | 6.4572 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: PR-18  | Location: Patuxent River Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 2.1 Salinity (ppt): 6.49 Temperature (C): 1 | Dissolved Oxygen (mg/l): 4.6 Sediment Silt-Clay (%): 88.56 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 4.60 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.77 5 Pollution Indicative Species Abundance (%) 5 | Abundance (#/m2) 2116 5 Pollution Indicative Species Biomass (%) 1 | Biomass (g/m2) 2.66 3 Pollution Sensitive Species Abundance (%) 20 | Carnivore-Omnivore Abundance (%) 16.30 Pollution Sensitive Species Biomass (%) 87 | Deep Deposit Feeder Abundance (%) 35.87  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 667 | 667.0 667 6 | Leptocheirus plumulosus | 644 | 644.0 644 6 | Cyathura polita | 184 | 184.0 184 1 | Macoma balthica | 184 | 184.0 184 1 | Melita nitida (Epi) | 92 | 92.0 92  | Carinoma tremaphoros | 69 | 69.0 69  | Neanthes succinea | 69 | 69.0 69  | Macoma mitchelli | 69 | 69.0 69  | Imm. Tubificid w/o Cap. Chaete | 46 | 46.0 46  | Heteromastus filiformis | 46 | 46.0 46  | Marenzelleria viridis | 46 | 46.0 46  | Streblospio benedicti | 46 | 46.0 46  | Hypereteone heteropoda | 23 | 23.0 23  | Rangia cuneata | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000 

 --------------------------------------------------------------------------------------------------------- | Number of Species | 14 |  | Number of Species (w/o Epifauna) | 13 |  | Abundance | 2208 |  | Abundance (w/o Epifauna) | 2116 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  --------------------------------------------------------------------------------------------------------- | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 1.8377 | 1.8377 1.8377 1.8 | Cyathura polita | 0.2530 | 0.2530 0.2530 0.2 | Rangia cuneata | 0.2047 | 0.2047 0.2047 0.2 | Macoma mitchelli | 0.1150 | 0.1150 0.1150 0.1 | Leptocheirus plumulosus | 0.1058 | 0.1058 0.1058 0.1 | Hypereteone heteropoda | 0.0414 | 0.0414 0.0414 0.0 | Marenzelleria viridis | 0.0368 | 0.0368 0.0368 0.0 | Neanthes succinea | 0.0322 | 0.0322 0.0322 0.0 | Heteromastus filiformis | 0.0161 | 0.0161 0.0161 0.0 | Carinoma tremaphoros | 0.0138 | 0.0138 0.0138 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Melita nitida (Epi) | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 2.6646 |  | Biomass (w/o Epifauna) | 2.6634 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: PR-19  | Location: Patuxent River Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.2 Salinity (ppt): 6.41 Temperature (C): 2 | Dissolved Oxygen (mg/l): 3.6 Sediment Silt-Clay (%): 18.74 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.40 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 3.01 5 Pollution Indicative Species Abundance (%) 13 | Abundance (#/m2) 2737 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 181.06 1 Pollution Sensitive Species Abundance (%) 31 | Carnivore-Omnivore Abundance (%) 26.05 Pollution Sensitive Species Biomass (%) 99 | Deep Deposit Feeder Abundance (%) 28.57  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 690 | 690.0 690 6 | Rangia cuneata | 667 | 667.0 667 6 | Streblospio benedicti | 345 | 345.0 345 3 | Carinoma tremaphoros | 253 | 253.0 253 2 | Neanthes succinea | 253 | 253.0 253 2 | Laeonereis culveri | 138 | 138.0 138 1 | Marenzelleria viridis | 92 | 92.0 92  | Heteromastus filiformis | 69 | 69.0 69  | Polydora cornuta | 69 | 69.0 69  | Cyathura polita | 69 | 69.0 69  | Macoma balthica | 46 | 46.0 46  | Imm. Tubificid w/o Cap. Chaete | 23 | 23.0 23  | Mytilopsis leucophaeata (Epi)| 23 | 23.0 23  | Leptocheirus plumulosus | 23 | 23.0 23  | Gammarus daiberi (Epi) | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 --------------------------------------------------------------------------------------------------------- | Number of Species | 15 |  | Number of Species (w/o Epifauna) | 13 |  | Abundance | 2783 |  | Abundance (w/o Epifauna) | 2737 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  --------------------------------------------------------------------------------------------------------- | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Rangia cuneata | 179.9911 |179.9911 179.9911 179.9 | Marenzelleria viridis | 0.3289 | 0.3289 0.3289 0.3 | Neanthes succinea | 0.2760 | 0.2760 0.2760 0.2 | Macoma balthica | 0.2507 | 0.2507 0.2507 0.2 | Mytilopsis leucophaeata (Epi)| 0.2392 | 0.2392 0.2392 0.2 | Laeonereis culveri | 0.0690 | 0.0690 0.0690 0.0 | Cyathura polita | 0.0621 | 0.0621 0.0621 0.0 | Heteromastus filiformis | 0.0368 | 0.0368 0.0368 0.0 | Carinoma tremaphoros | 0.0345 | 0.0345 0.0345 0.0 | Polydora cornuta | 0.0092 | 0.0092 0.0092 0.0 | Gammarus spp. (Epi) | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Leptocheirus plumulosus | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 181.3090 |  | Biomass (w/o Epifauna) | 181.0629 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: PR-20  | Location: Patuxent River Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.9 Salinity (ppt): 6.13 Temperature (C): 1 | Dissolved Oxygen (mg/l): 4.2 Sediment Silt-Clay (%): 73.78 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.00 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 3.01 5 Pollution Indicative Species Abundance (%) 36 | Abundance (#/m2) 2898 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 117.59 1 Pollution Sensitive Species Abundance (%) 12 | Carnivore-Omnivore Abundance (%) 23.02 Pollution Sensitive Species Biomass (%) 99 | Deep Deposit Feeder Abundance (%) 27.78  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 920 | 920.0 920 9 | Tubificoides spp. | 621 | 621.0 621 6 | Neanthes succinea | 299 | 299.0 299 2 | Carinoma tremaphoros | 253 | 253.0 253 2 | Rangia cuneata | 207 | 207.0 207 2 | Rhithropanopeus harrisi (Epi)| 138 | 138.0 138 1 | Polydora cornuta | 138 | 138.0 138 1 | Imm. Tubificid w/o Cap. Chaete | 115 | 115.0 115 1 | Cyathura polita | 92 | 92.0 92  | Gammarus daiberi (Epi) | 92 | 92.0 92  | Heteromastus filiformis | 69 | 69.0 69  | Marenzelleria viridis | 46 | 46.0 46  | Macoma mitchelli | 46 | 46.0 46  | Hypereteone heteropoda | 23 | 23.0 23  | Leptocheirus plumulosus | 23 | 23.0 23  | Ameroculodes species complex | 23 | 23.0 23  | Macoma balthica | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 --------------------------------------------------------------------------------------------------------- | Number of Species | 17 |  | Number of Species (w/o Epifauna)| 15 |  | Abundance | 3122 |  | Abundance (w/o Epifauna) | 2898 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (per sq. meter)  --------------------------------------------------------------------------------------------------------- | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Rangia cuneata | 116.4766 |116.4766 116.4766 116.4 | Rhithropanopeus harrisi (Epi)| 0.7636 | 0.7636 0.7636 0.7 | Macoma balthica | 0.3105 | 0.3105 0.3105 0.3 | Neanthes succinea | 0.2921 | 0.2921 0.2921 0.2 | Cyathura polita | 0.1679 | 0.1679 0.1679 0.1 | Marenzelleria viridis | 0.1403 | 0.1403 0.1403 0.1 | Macoma mitchelli | 0.0782 | 0.0782 0.0782 0.0 | Carinoma tremaphoros | 0.0391 | 0.0391 0.0391 0.0 | Hypereteone heteropoda | 0.0368 | 0.0368 0.0368 0.0 | Heteromastus filiformis | 0.0253 | 0.0253 0.0253 0.0 | Gammarus spp. (Epi) | 0.0161 | 0.0161 0.0161 0.0 | Streblospio benedicti | 0.0115 | 0.0115 0.0115 0.0 | Polydora cornuta | 0.0046 | 0.0046 0.0046 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 | Leptocheirus plumulosus | 0.0012 | 0.0012 0.0012 0.0 | Ameroculodes species complex | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 118.3683 |  | Biomass (w/o Epifauna) | 117.5886 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: PR-21  | Location: Patuxent River Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.8 Salinity (ppt): 5.90 Temperature (C): 2 | Dissolved Oxygen (mg/l): 4.6 Sediment Silt-Clay (%): 92.04 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.00 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.30 3 Pollution Indicative Species Abundance (%) 15 | Abundance (#/m2) 1334 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 61.32 1 Pollution Sensitive Species Abundance (%) 10 | Carnivore-Omnivore Abundance (%) 20.69 Pollution Sensitive Species Biomass (%) 99 | Deep Deposit Feeder Abundance (%) 48.28  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 621 | 621.0 621 6 | Carinoma tremaphoros | 253 | 253.0 253 2 | Streblospio benedicti | 207 | 207.0 207 2 | Marenzelleria viridis | 69 | 69.0 69  | Macoma mitchelli | 69 | 69.0 69  | Rangia cuneata | 46 | 46.0 46  | Heteromastus filiformis | 23 | 23.0 23  | Leptocheirus plumulosus | 23 | 23.0 23  | Cyathura polita | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 9 |  | Number of Species (w/o Epifauna) | 9 |  | Abundance | 1334 |  | Abundance (w/o Epifauna) | 1334 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Rangia cuneata | 60.3934 | 60.3934 60.3934 60.3 | Marenzelleria viridis | 0.7130 | 0.7130 0.7130 0.7 | Macoma mitchelli | 0.0621 | 0.0621 0.0621 0.0 | Heteromastus filiformis | 0.0529 | 0.0529 0.0529 0.0 | Cyathura polita | 0.0506 | 0.0506 0.0506 0.0 | Carinoma tremaphoros | 0.0414 | 0.0414 0.0414 0.0 | Streblospio benedicti | 0.0046 | 0.0046 0.0046 0.0 | Leptocheirus plumulosus | 0.0023 | 0.0023 0.0023 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 61.3214 |  | Biomass | 61.3214 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: PR-22  | Location: Patuxent River Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 4.6 Salinity (ppt): 4.25 Temperature (C): 1 | Dissolved Oxygen (mg/l): 5.0 Sediment Silt-Clay (%): 98.25 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 1.40 Condition: Severely Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 1.51 1 Pollution Indicative Species Abundance (%) 15 | Abundance (#/m2) 299 1 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 0.01 1 Pollution Sensitive Species Abundance (%) 0 | Carnivore-Omnivore Abundance (%) 7.69 Pollution Sensitive Species Biomass (%) 33 | Deep Deposit Feeder Abundance (%) 76.92  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 207 | 207.0 207 2 | Carinoma tremaphoros | 23 | 23.0 23  | Imm. Tubificid w/o Cap. Chaete | 23 | 23.0 23  | Streblospio benedicti | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 5 |  | Number of Species (w/o Epifauna) | 5 |  | Abundance | 299 |  | Abundance (w/o Epifauna) | 299 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 0.0023 | 0.0023 0.0023 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Carinoma tremaphoros | 0.0012 | 0.0012 0.0012 0.0 | Macoma mitchelli | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 0.0069 |  | Biomass (w/o Epifauna) | 0.0069 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-01  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.1 Salinity (ppt): 4.65 Temperature (C): 1 | Dissolved Oxygen (mg/l): 5.7 Sediment Silt-Clay (%): 99.22 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.40 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.56 5 Pollution Indicative Species Abundance (%) 22 | Abundance (#/m2) 506 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 2.27 3 Pollution Sensitive Species Abundance (%) 18 | Carnivore-Omnivore Abundance (%) 36.36 Pollution Sensitive Species Biomass (%) 87 | Deep Deposit Feeder Abundance (%) 18.18  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 138 | 138.0 138 1 | Coelotanypus spp. | 115 | 115.0 115 1 | Tubificoides spp. | 92 | 92.0 92  | Macoma balthica | 69 | 69.0 69  | Carinoma tremaphoros | 46 | 46.0 46  | Cyathura polita | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 7 |  | Number of Species (w/o Epifauna) | 7 |  | Abundance | 506 |  | Abundance (w/o Epifauna) | 506 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 1.8262 | 1.8262 1.8262 1.8 | Macoma mitchelli | 0.1840 | 0.1840 0.1840 0.1 | Cyathura polita | 0.1518 | 0.1518 0.1518 0.1 | Leptocheirus plumulosus | 0.0713 | 0.0713 0.0713 0.0 | Carinoma tremaphoros | 0.0184 | 0.0184 0.0184 0.0 | Coelotanypus spp. | 0.0161 | 0.0161 0.0161 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 2.2724 |  | Biomass (w/o Epifauna) | 2.2724 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-03  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.1 Salinity (ppt): 5.03 Temperature (C): 1 | Dissolved Oxygen (mg/l): 5.3 Sediment Silt-Clay (%): 97.16 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 2.60 Condition: Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 2.60 5 Pollution Indicative Species Abundance (%) 25 | Abundance (#/m2) 460 1 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 4.21 3 Pollution Sensitive Species Abundance (%) 30 | Carnivore-Omnivore Abundance (%) 40.00 Pollution Sensitive Species Biomass (%) 96 | Deep Deposit Feeder Abundance (%) 20.00  | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Coelotanypus spp. | 115 | 115.0 115 1 | Tubificoides spp. | 92 | 92.0 92  | Macoma balthica | 92 | 92.0 92  | Leptocheirus plumulosus | 69 | 69.0 69  | Cyathura polita | 46 | 46.0 46  | Carinoma tremaphoros | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 7 |  | Number of Species (w/o Epifauna) | 7 |  | Abundance | 460 |  | Abundance (w/o Epifauna) | 460 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 3.9146 | 3.9146 3.9146 3.9 | Cyathura polita | 0.1311 | 0.1311 0.1311 0.1 | Macoma mitchelli | 0.1311 | 0.1311 0.1311 0.1 | Coelotanypus spp. | 0.0161 | 0.0161 0.0161 0.0 | Leptocheirus plumulosus | 0.0115 | 0.0115 0.0115 0.0 | Carinoma tremaphoros | 0.0046 | 0.0046 0.0046 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 4.2101 |  | Biomass (w/o Epifauna) | 4.2101 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-05  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.8 Salinity (ppt): 3.95 Temperature (C): 1 | Dissolved Oxygen (mg/l): 7.0 Sediment Silt-Clay (%): 71.66 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 2.60 Condition: Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 2.97 5 Pollution Indicative Species Abundance (%) 23 | Abundance (#/m2) 897 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 0.86 1 Pollution Sensitive Species Abundance (%) 15 | Carnivore-Omnivore Abundance (%) 35.90 Pollution Sensitive Species Biomass (%) 52 | Deep Deposit Feeder Abundance (%) 33.33  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 253 | 253.0 253 2 | Streblospio benedicti | 184 | 184.0 184 1 | Laeonereis culveri | 115 | 115.0 115 1 | Carinoma tremaphoros | 92 | 92.0 92  | Cyathura polita | 69 | 69.0 69  | Heteromastus filiformis | 46 | 46.0 46  | Rangia cuneata | 46 | 46.0 46  | Chironomus spp. | 23 | 23.0 23  | Edwardsia elegans | 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 --------------------------------------------------------------------------------------------------------- | Number of Species | 11 |  | Number of Species (w/o Epifauna) | 11 |  | Abundance | 897 |  | Abundance (w/o Epifauna) | 897 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Laeonereis culveri | 0.2691 | 0.2691 0.2691 0.2 | Cyathura polita | 0.2346 | 0.2346 0.2346 0.2 | Marenzelleria viridis | 0.1265 | 0.1265 0.1265 0.1 | Rangia cuneata | 0.0874 | 0.0874 0.0874 0.0 | Heteromastus filiformis | 0.0644 | 0.0644 0.0644 0.0 | Carinoma tremaphoros | 0.0598 | 0.0598 0.0598 0.0 | Macoma mitchelli | 0.0138 | 0.0138 0.0138 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Edwardsia elegans | 0.0012 | 0.0012 0.0012 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Chironomidae larvae | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 0.8602 |  | Biomass (w/o Epifauna) | 0.8602 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-06  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 99.32 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.80 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.37 3 Pollution Indicative Species Abundance (%) 9 | Abundance (#/m2) 506 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 4.65 3 Pollution Sensitive Species Abundance (%) 40 | Carnivore-Omnivore Abundance (%) 18.18 Pollution Sensitive Species Biomass (%) 94 | Deep Deposit Feeder Abundance (%) 27.27  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 161 | 161.0 161 1 | Tubificoides spp. | 138 | 138.0 138 1 | Leptocheirus plumulosus | 69 | 69.0 69  | Coelotanypus spp. | 46 | 46.0 46  | Cyathura polita | 46 | 46.0 46  | Macoma mitchelli | 46 | 46.0 46  --------------------------------------------------------------------------------------------------------- | Number of Species | 6 |  | Number of Species (w/o Epifauna) | 6 |  | Abundance | 506 |  | Abundance (w/o Epifauna) | 506 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 4.1814 | 4.1814 4.1814 4.1 | Cyathura polita | 0.2277 | 0.2277 0.2277 0.2 | Macoma mitchelli | 0.2277 | 0.2277 0.2277 0.2 | Leptocheirus plumulosus | 0.0115 | 0.0115 0.0115 0.0 | Coelotanypus spp. | 0.0046 | 0.0046 0.0046 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 4.6540 |  | Biomass (w/o Epifauna) | 4.6540 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-07  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6, 2000  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.8 Salinity (ppt): 4.07 Temperature (C): 1 | Dissolved Oxygen (mg/l): 6.8 Sediment Silt-Clay (%): 92.44 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 2.20 Condition: Marginal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.68 5 Pollution Indicative Species Abundance (%) 10 | Abundance (#/m2) 437 1 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 0.60 1 Pollution Sensitive Species Abundance (%) 21 | Carnivore-Omnivore Abundance (%) 57.89 Pollution Sensitive Species Biomass (%) 38 | Deep Deposit Feeder Abundance (%) 26.32  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Carinoma tremaphoros | 115 | 115.0 115 1 | Tubificoides spp. | 69 | 69.0 69  | Laeonereis culveri | 69 | 69.0 69  | Cyathura polita | 69 | 69.0 69  | Heteromastus filiformis | 46 | 46.0 46  | Streblospio benedicti | 46 | 46.0 46  | Marenzelleria viridis | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 7 |  | Number of Species (w/o Epifauna) | 7 |  | Abundance | 437 |  | Abundance (w/o Epifauna) | 437 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Laeonereis culveri | 0.2208 | 0.2208 0.2208 0.2 | Cyathura polita | 0.1955 | 0.1955 0.1955 0.1 | Carinoma tremaphoros | 0.1104 | 0.1104 0.1104 0.1 | Heteromastus filiformis | 0.0345 | 0.0345 0.0345 0.0 | Marenzelleria viridis | 0.0322 | 0.0322 0.0322 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 0.5957 |  | Biomass | 0.5957 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-08  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 99.15 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.80 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.72 5 Pollution Indicative Species Abundance (%) 13 | Abundance (#/m2) 1035 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 4.78 3 Pollution Sensitive Species Abundance (%) 31 | Carnivore-Omnivore Abundance (%) 31.11 Pollution Sensitive Species Biomass (%) 91 | Deep Deposit Feeder Abundance (%) 28.89  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 276 | 276.0 276 2 | Macoma balthica | 207 | 207.0 207 2 | Leptocheirus plumulosus | 184 | 184.0 184 1 | Coelotanypus spp. | 138 | 138.0 138 1 | Cyathura polita | 115 | 115.0 115 1 | Carinoma tremaphoros | 46 | 46.0 46  | Heteromastus filiformis | 23 | 23.0 23  | Neanthes succinea | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 9 |  | Number of Species (w/o Epifauna) | 9 |  | Abundance | 1065 |  | Abundance (w/o Epifauna) | 1035 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 3.8778 | 3.8778 3.8778 3.8 | Cyathura polita | 0.5129 | 0.5129 0.5129 0.5 | Macoma mitchelli | 0.1748 | 0.1748 0.1748 0.1 | Leptocheirus plumulosus | 0.1058 | 0.1058 0.1058 0.1 | Coelotanypus spp. | 0.0345 | 0.0345 0.0345 0.0 | Heteromastus filiformis | 0.0322 | 0.0322 0.0322 0.0 | Carinoma tremaphoros | 0.0299 | 0.0299 0.0299 0.0 | Tubificoides spp. | 0.0069 | 0.0069 0.0069 0.0 | Neanthes succinea | 0.0046 | 0.0046 0.0046 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 4.7794 |  | Biomass (w/o Epifauna) | 4.7794 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-09  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.1 Salinity (ppt): 5.37 Temperature (C): 1 | Dissolved Oxygen (mg/l): 5.1 Sediment Silt-Clay (%): 99.51 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 4.20 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.59 5 Pollution Indicative Species Abundance (%) 17 | Abundance (#/m2) 529 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 9.54 5 Pollution Sensitive Species Abundance (%) 30 | Carnivore-Omnivore Abundance (%) 39.13 Pollution Sensitive Species Biomass (%) 95 | Deep Deposit Feeder Abundance (%) 4.35  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 161 | 161.0 161 1 | Coelotanypus spp. | 92 | 92.0 92  | Macoma balthica | 92 | 92.0 92  | Cyathura polita | 69 | 69.0 69  | Carinoma tremaphoros | 46 | 46.0 46  | Macoma mitchelli | 46 | 46.0 46  | Heteromastus filiformis | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 7 |  | Number of Species (w/o Epifauna) | 7 |  | Abundance | 529 |  | Abundance (w/o Epifauna) | 529 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 8.8113 | 8.8113 8.8113 8.8 | Macoma mitchelli | 0.3105 | 0.3105 0.3105 0.3 | Cyathura polita | 0.2760 | 0.2760 0.2760 0.2 | Leptocheirus plumulosus | 0.0943 | 0.0943 0.0943 0.0 | Carinoma tremaphoros | 0.0253 | 0.0253 0.0253 0.0 | Coelotanypus spp. | 0.0138 | 0.0138 0.0138 0.0 | Heteromastus filiformis | 0.0115 | 0.0115 0.0115 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 9.5427 |  | Biomass | 9.5427 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-11  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.4 Salinity (ppt): 5.31 Temperature (C): 1 | Dissolved Oxygen (mg/l): 5.6 Sediment Silt-Clay (%): 98.67 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.80 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.74 5 Pollution Indicative Species Abundance (%) 19 | Abundance (#/m2) 966 3 Pollution Indicative Species Biomass (%) 1 | Biomass (g/m2) 3.00 3 Pollution Sensitive Species Abundance (%) 21 | Carnivore-Omnivore Abundance (%) 33.33 Pollution Sensitive Species Biomass (%) 87 | Deep Deposit Feeder Abundance (%) 16.67  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Leptocheirus plumulosus | 299 | 299.0 299 2 | Coelotanypus spp. | 161 | 161.0 161 1 | Tubificoides spp. | 138 | 138.0 138 1 | Macoma balthica | 138 | 138.0 138 1 | Carinoma tremaphoros | 92 | 92.0 92  | Cyathura polita | 69 | 69.0 69  | Heteromastus filiformis | 23 | 23.0 23  | Streblospio benedicti | 23 | 23.0 23  | Macoma mitchelli | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 9 |  | Number of Species (w/o Epifauna) | 9 |  | Abundance | 966 |  | Abundance (w/o Epifauna) | 966 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 2.3736 | 2.3736 2.3736 2.3 | Cyathura polita | 0.2576 | 0.2576 0.2576 0.2 | Leptocheirus plumulosus | 0.1380 | 0.1380 0.1380 0.1 | Macoma mitchelli | 0.0920 | 0.0920 0.0920 0.0 | Carinoma tremaphoros | 0.0506 | 0.0506 0.0506 0.0 | Heteromastus filiformis | 0.0483 | 0.0483 0.0483 0.0 | Coelotanypus spp. | 0.0345 | 0.0345 0.0345 0.0 | Streblospio benedicti | 0.0046 | 0.0046 0.0046 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 3.0015 |  | Biomass (w/o Epifauna) | 3.0015 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-12  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.1 Salinity (ppt): 5.03 Temperature (C): 1 | Dissolved Oxygen (mg/l): 5.1 Sediment Silt-Clay (%): 98.87 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.00 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.21 3 Pollution Indicative Species Abundance (%) 12 | Abundance (#/m2) 920 3 Pollution Indicative Species Biomass (%) 1 | Biomass (g/m2) 1.62 3 Pollution Sensitive Species Abundance (%) 5 | Carnivore-Omnivore Abundance (%) 15.00 Pollution Sensitive Species Biomass (%) 47 | Deep Deposit Feeder Abundance (%) 47.50  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 437 | 437.0 437 4 | Leptocheirus plumulosus | 184 | 184.0 184 1 | Macoma mitchelli | 115 | 115.0 115 1 | Coelotanypus spp. | 92 | 92.0 92  | Carinoma tremaphoros | 23 | 23.0 23  | Streblospio benedicti | 23 | 23.0 23  | Cyathura polita | 23 | 23.0 23  | Macoma balthica | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 7 |  | Number of Species (w/o Epifauna) | 7 |  | Abundance | 920 |  | Abundance (w/o Epifauna) | 920 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma mitchelli | 0.7475 | 0.7475 0.7475 0.7 | Macoma balthica | 0.5704 | 0.5704 0.5704 0.5 | Cyathura polita | 0.1978 | 0.1978 0.1978 0.1 | Leptocheirus plumulosus | 0.0575 | 0.0575 0.0575 0.0 | Coelotanypus spp. | 0.0230 | 0.0230 0.0230 0.0 | Carinoma tremaphoros | 0.0115 | 0.0115 0.0115 0.0 | Tubificoides spp. | 0.0092 | 0.0092 0.0092 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 1.6180 |  | Biomass (w/o Epifauna) | 1.6180 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-13  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.2 Salinity (ppt): 5.87 Temperature (C): 1 | Dissolved Oxygen (mg/l): 4.6 Sediment Silt-Clay (%): 98.90 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.80 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.35 3 Pollution Indicative Species Abundance (%) 7 | Abundance (#/m2) 1219 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 4.66 3 Pollution Sensitive Species Abundance (%) 54 | Carnivore-Omnivore Abundance (%) 32.08 Pollution Sensitive Species Biomass (%) 96 | Deep Deposit Feeder Abundance (%) 5.66  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 437 | 437.0 437 4 | Leptocheirus plumulosus | 322 | 322.0 322 3 | Cyathura polita | 230 | 230.0 230 2 | Coelotanypus spp. | 92 | 92.0 92  | Tubificoides spp. | 46 | 46.0 46  | Carinoma tremaphoros | 46 | 46.0 46  | Heteromastus filiformis | 23 | 23.0 23  | Neanthes succinea | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 8 |  | Number of Species (w/o Epifauna) | 8 |  | Abundance | 1219 |  | Abundance (w/o Epifauna) | 1219 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 4.0572 | 4.0572 4.0572 4.0 | Cyathura polita | 0.4439 | 0.4439 0.4439 0.4 | Leptocheirus plumulosus | 0.1012 | 0.1012 0.1012 0.1 | Neanthes succinea | 0.0207 | 0.0207 0.0207 0.0 | Carinoma tremaphoros | 0.0184 | 0.0184 0.0184 0.0 | Coelotanypus spp. | 0.0115 | 0.0115 0.0115 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Heteromastus filiformis | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 4.6552 |  | Biomass (w/o Epifauna) | 4.6552 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-14  | Location: Swanson’ Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.1 Salinity (ppt): 5.25 Temperature (C): 1 | Dissolved Oxygen (mg/l): 4.9 Sediment Silt-Clay (%): 99.10 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 2.60 Condition: Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 2.37 3 Pollution Indicative Species Abundance (%) 42 | Abundance (#/m2) 874 3 Pollution Indicative Species Biomass (%) 3 | Biomass (g/m2) 2.71 3 Pollution Sensitive Species Abundance (%) 18 | Carnivore-Omnivore Abundance (%) 50.00 Pollution Sensitive Species Biomass (%) 68 | Deep Deposit Feeder Abundance (%) 13.16  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Coelotanypus spp. | 368 | 368.0 368 3 | Leptocheirus plumulosus | 184 | 184.0 184 1 | Macoma balthica | 92 | 92.0 92  | Tubificoides spp. | 69 | 69.0 69  | Cyathura polita | 69 | 69.0 69  | Heteromastus filiformis | 46 | 46.0 46  | Macoma mitchelli | 46 | 46.0 46  --------------------------------------------------------------------------------------------------------- | Number of Species | 7 |  | Number of Species (w/o Epifauna) | 7 |  | Abundance | 874 |  | Abundnace (w/o Epifauna) | 874 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma balthica | 1.7204 | 1.7204 1.7204 1.7 | Macoma mitchelli | 0.5543 | 0.5543 0.5543 0.5 | Cyathura polita | 0.1426 | 0.1426 0.1426 0.1 | Heteromastus filiformis | 0.1311 | 0.1311 0.1311 0.1 | Coelotanypus spp. | 0.0897 | 0.0897 0.0897 0.0 | Leptocheirus plumulosus | 0.0690 | 0.0690 0.0690 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 2.7094 |  | Biomass | 2.7094 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-15  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 1.1 Salinity (ppt): 4.55 Temperature (C): 1 | Dissolved Oxygen (mg/l): 5.3 Sediment Silt-Clay (%): 62.86 Total Carbon (%):  ========================================================================================================= ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.80 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.88 5 Pollution Indicative Species Abundance (%) 3 | Abundance (#/m2) 667 3 Pollution Indicative Species Biomass (%) 2 | Biomass (g/m2) 1.59 3 Pollution Sensitive Species Abundance (%) 27 | Carnivore-Omnivore Abundance (%) 37.93 Pollution Sensitive Species Biomass (%) 52 | Deep Deposit Feeder Abundance (%) 10.34  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Carinoma tremaphoros | 138 | 138.0 138 1 | Macoma mitchelli | 138 | 138.0 138 1 | Leptocheirus plumulosus | 115 | 115.0 115 1 | Cyathura polita | 92 | 92.0 92  | Tubificoides spp. | 69 | 69.0 69  | Rangia cuneata | 46 | 46.0 46  | Coelotanypus spp. | 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  | Macoma balthica | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 9 |  | Numnber of Species (w/o Epifauna) | 9 |  | Abundance | 667 |  | Abundnance (w/o Epifauna) | 667 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter) -  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma mitchelli | 0.6371 | 0.6371 0.6371 0.6 | Macoma balthica | 0.5589 | 0.5589 0.5589 0.5 | Cyathura polita | 0.1932 | 0.1932 0.1932 0.1 | Rangia cuneata | 0.0805 | 0.0805 0.0805 0.0 | Coelotanypus spp. | 0.0391 | 0.0391 0.0391 0.0 | Carinoma tremaphoros | 0.0368 | 0.0368 0.0368 0.0 | Leptocheirus plumulosus | 0.0322 | 0.0322 0.0322 0.0 | Marenzelleria viridis | 0.0069 | 0.0069 0.0069 0.0 | Tubificoides spp. | 0.0023 | 0.0023 0.0023 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 1.5870 |  | Biomass (w/o Epifauna) | 1.5870 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-16  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6, 20 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.6 Salinity (ppt): 4.58 Temperature (C): 2 | Dissolved Oxygen (mg/l): 6.9 Sediment Silt-Clay (%): 75.97 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 2.20 Condition: Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 2.24 3 Pollution Indicative Species Abundance (%) 36 | Abundance (#/m2) 3841 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 2.62 3 Pollution Sensitive Species Abundance (%) 3 | Carnivore-Omnivore Abundance (%) 14.97 Pollution Sensitive Species Biomass (%) 15 | Deep Deposit Feeder Abundance (%) 44.31  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 1541 | 1541.0 1541 15 | Streblospio benedicti | 1380 | 1380.0 1380 13 | Laeonereis culveri | 345 | 345.0 345 3 | Heteromastus filiformis | 138 | 138.0 138 1 | Cyathura polita | 115 | 115.0 115 1 | Hobsonia florida | 92 | 92.0 92  | Edwardsia elegans | 46 | 46.0 46  | Macoma mitchelli | 46 | 46.0 46  | Carinoma tremaphoros | 23 | 23.0 23  | Imm. Tubificid w/o Cap. Chaete | 23 | 23.0 23  | Tanytarsus spp. | 23 | 23.0 23  | Neanthes succinea | 23 | 23.0 23  | Polydora cornuta | 23 | 23.0 23  | Edotea triloba (Epi) | 23 | 23.0 23  | Rangia cuneata | 23 | 23.0 23  | Apocorophium lacustre (Epi) | 23 | 23.0 23  =========================================================================================================
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 --------------------------------------------------------------------------------------------------------- | Gammarus daiberi (Epi) | 23 | 23.0 23  | Hirudinea (Epi) | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 18 |  | Number of Species (w/o Epifauna) | 14 |  | Abundance | 3933 |  | Abundance (w/o Epifauna) | 3841 |  --------------------------------------------------------------------------------------------------------- | BENTHIC BIOMASS (Grams per sq. meter) -  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Laeonereis culveri | 1.6077 | 1.6077 1.6077 1.6 | Cyathura polita | 0.4094 | 0.4094 0.4094 0.4 | Macoma mitchelli | 0.3312 | 0.3312 0.3312 0.3 | Heteromastus filiformis | 0.1357 | 0.1357 0.1357 0.1 | Neanthes succinea | 0.0460 | 0.0460 0.0460 0.0 | Carinoma tremaphoros | 0.0391 | 0.0391 0.0391 0.0 | Streblospio benedicti | 0.0184 | 0.0184 0.0184 0.0 | Tubificoides spp. | 0.0138 | 0.0138 0.0138 0.0 | Hirudinea (Epi) | 0.0115 | 0.0115 0.0115 0.0 | Gammarus spp. (Epi) | 0.0115 | 0.0115 0.0115 0.0 | Edotea triloba (Epi) | 0.0092 | 0.0092 0.0092 0.0 | Hobsonia florida | 0.0092 | 0.0092 0.0092 0.0 | Edwardsia elegans | 0.0069 | 0.0069 0.0069 0.0 | Polydora cornuta | 0.0012 | 0.0012 0.0012 0.0 | Rangia cuneata | 0.0012 | 0.0012 0.0012 0.0 | Apocorophium lacustre (Epi) | 0.0012 | 0.0012 0.0012 0.0 | Chironomidae larvae | 0.0012 | 0.0012 0.0012 0.0 | Oligochaeta | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 2.6554 |  | Biomass (w/o Epifauna) | 2.6220 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-17  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6, 2 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.8 Salinity (ppt): 4.05 Temperature (C): 1 | Dissolved Oxygen (mg/l): 6.5 Sediment Silt-Clay (%): 92.42 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.00 Condition: Marginal # Attributes Score | Value Score Va | Shannon-Weiner Index 1.00 1 Pollution Indicative Species Abundance (%) 84 | Abundance (#/m2) 575 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 0.50 1 Pollution Sensitive Species Abundance (%) 12 | Carnivore-Omnivore Abundance (%) 16.00 Pollution Sensitive Species Biomass (%) 97 | Deep Deposit Feeder Abundance (%) 80.00  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 460 | 460.0 460 4 | Cyathura polita | 69 | 69.0 69  | Carinoma tremaphoros | 23 | 23.0 23  | Streblospio benedicti | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 4 |  | Number of Species (w/o Epifauna) | 4 |  | Abundance | 575 |  | Abundance (w/o Epifauna) | 575 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter) -  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Cyathura polita | 0.4876 | 0.4876 0.4876 0.4 | Carinoma tremaphoros | 0.0092 | 0.0092 0.0092 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 0.5025 |  | Biomass | 0.5025 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-18  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 97.48 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 1.80 Condition: Severely Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 0.54 1 Pollution Indicative Species Abundance (%) 0 | Abundance (#/m2) 184 1 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 0.10 1 Pollution Sensitive Species Abundance (%) 0 | Carnivore-Omnivore Abundance (%) 0.00 Pollution Sensitive Species Biomass (%) 0 | Deep Deposit Feeder Abundance (%) 100.00  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 161 | 161.0 161 1 | Heteromastus filiformis | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 2 |  | Number of Species (w/o Epifauna) | 2 |  | Abundance | 184 |  | Abundance (w/o Epifauna) | 184 |  ======================================================================================================== | BENTHIC BIOMASS (Grams per sq. meter) -  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Heteromastus filiformis | 0.0966 | 0.0966 0.0966 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 0.0978 |  | Biomass (w/o Epifauna) | 0.0978 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-19  | Location: Swanson’s Creek Habitat: Oligohaline Date: September 6 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.6 Salinity (ppt): 2.84 Temperature (C): 2 | Dissolved Oxygen (mg/l): 7.5 Sediment Silt-Clay (%): 94.45 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 3.80 Condition: Meets Goal # Attributes Score | Value Score Va | Shannon-Weiner Index 2.73 Oligohaline Pollution Indicative Spp. Abund. 26 | Abundance (#/m2) 690 Tolerance Score 9 | Biomass (g/m2) 3.03 Oligohaline Pollution Sensitive Spp. Abund. 16 | Carnivore-Omnivore Abundance (%) 63.33 Tanypodinae/Chironomidae Abundance Ratio 0 | Deep Deposit Feeder Abundance (%) 6.67 5  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Laeonereis culveri | 207 | 207.0 207 2 | Marenzelleria viridis | 115 | 115.0 115 1 | Cyathura polita | 115 | 115.0 115 1 | Chironomus spp. | 69 | 69.0 69  | Streblospio benedicti | 69 | 69.0 69  | Tubificoides spp. | 46 | 46.0 46  | Carinoma tremaphoros | 46 | 46.0 46  | Macoma mitchelli | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 7 |  | Number of Species (w/o Epifauna) | 7 |  | Abundance | 690 |  | Abundance (w/o Epifauna) | 690 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Laeonereis culveri | 1.0005 | 1.0005 1.0005 1.0 | Marenzelleria viridis | 0.7705 | 0.7705 0.7705 0.7 | Cyathura polita | 0.6279 | 0.6279 0.6279 0.6 | Macoma mitchelli | 0.5589 | 0.5589 0.5589 0.5 | Carinoma tremaphoros | 0.0736 | 0.0736 0.0736 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Chironomidae larvae | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 3.0348 |  | Biomass (w/o Epifauna) | 3.0348 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-20  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6, 200 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.8 Salinity (ppt): 4.37 Temperature (C): 1 | Dissolved Oxygen (mg/l): 6.5 Sediment Silt-Clay (%): 97.20 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 2.60 Condition: Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 1.97 3 Pollution Indicative Species Abundance (%) 0 | Abundance (#/m2) 253 1 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 1.32 3 Pollution Sensitive Species Abundance (%) 9 | Carnivore-Omnivore Abundance (%) 9.09 Pollution Sensitive Species Biomass (%) 2 | Deep Deposit Feeder Abundance (%) 54.55  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Tubificoides spp. | 115 | 115.0 115 1 | Macoma mitchelli | 69 | 69.0 69  | Carinoma tremaphoros | 23 | 23.0 23  | Heteromastus filiformis | 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 5 |  | Number of Species (w/o Epifauna) | 5 |  | Abundance | 253 |  | Abundance (w/o Epifauna) | 253 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma mitchelli | 0.8993 | 0.8993 0.8993 0.8 | Carinoma tremaphoros | 0.3404 | 0.3404 0.3404 0.3 | Heteromastus filiformis | 0.0437 | 0.0437 0.0437 0.0 | Marenzelleria viridis | 0.0391 | 0.0391 0.0391 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 ---------------------------------------------------------------------------------------------------------- | Biomass | 1.3236 |  | Biomass (w/o Epifauna) | 1.3235 |  ----------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-21  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6, 2 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 2.4 Salinity (ppt): 4.43 Temperature (C): 2 | Dissolved Oxygen (mg/l): 7.0 Sediment Silt-Clay (%): 82.00 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 1.80 Condition: Severely Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 2.46 3 Pollution Indicative Species Abundance (%) 53 | Abundance (#/m2) 989 3 Pollution Indicative Species Biomass (%) 7 | Biomass (g/m2) 0.66 1 Pollution Sensitive Species Abundance (%) 9 | Carnivore-Omnivore Abundance (%) 32.56 Pollution Sensitive Species Biomass (%) 12 | Deep Deposit Feeder Abundance (%) 9.30  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Streblospio benedicti | 460 | 460.0 460 4 | Carinoma tremaphoros | 138 | 138.0 138 1 | Cyathura polita | 92 | 92.0 92  | Macoma mitchelli | 92 | 92.0 92  | Tubificoides spp. | 69 | 69.0 69  | Coelotanypus spp. | 69 | 69.0 69  | Edwardsia elegans | 23 | 23.0 23  | Procladius sublettei | 23 | 23.0 23  | Heteromastus filiformis | 23 | 23.0 23  | Gammarus daiberi (Epi) | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 10 |  | Number of Species (w/o Epifauna) | 9 |  | Abundance | 1012 |  | Abundance (w/o Epifauna) | 989 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Macoma mitchelli | 0.3335 | 0.3335 0.3335 0.3 | Carinoma tremaphoros | 0.1127 | 0.1127 0.1127 0.1 | Cyathura polita | 0.0851 | 0.0851 0.0851 0.0 | Heteromastus filiformis | 0.0759 | 0.0759 0.0759 0.0 | Streblospio benedicti | 0.0253 | 0.0253 0.0253 0.0 | Coelotanypus spp. | 0.0230 | 0.0230 0.0230 0.0 | Tubificoides spp. | 0.0046 | 0.0046 0.0046 0.0 | Gammarus spp. (Epi) | 0.0046 | 0.0046 0.0046 0.0 | Edwardsia elegans | 0.0023 | 0.0023 0.0023 0.0 | Chironomidae larvae | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 0.6682 |  | Biomass (w/o Epifauna) | 0.6636 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-22  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6,  | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): 0.8 Salinity (ppt): 4.31 Temperature (C): 1 | Dissolved Oxygen (mg/l): 6.5 Sediment Silt-Clay (%): 97.37 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 2.20 Condition: Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 2.46 3 Pollution Indicative Species Abundance (%) 21 | Abundance (#/m2) 644 3 Pollution Indicative Species Biomass (%) 0 | Biomass (g/m2) 0.66 1 Pollution Sensitive Species Abundance (%) 25 | Carnivore-Omnivore Abundance (%) 57.14 Pollution Sensitive Species Biomass (%) 45 | Deep Deposit Feeder Abundance (%) 14.29  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Neanthes succinea | 207 | 207.0 207 2 | Cyathura polita | 138 | 138.0 138 1 | Streblospio benedicti | 115 | 115.0 115 1 | Tubificoides spp. | 92 | 92.0 92  | Macoma mitchelli | 46 | 46.0 46  | Chironomus spp. | 23 | 23.0 23  | Marenzelleria viridis | 23 | 23.0 23  -------------------------------------------------------------------------------------------------------- | Number of Species | 7 |  | Number of Species (w/o Epifauna) | 7 |  | Abundance | 644 |  | Abundance (w/o Epifauna) | 644 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Neanthes succinea | 0.2852 | 0.2852 0.2852 0.2 | Cyathura polita | 0.2599 | 0.2599 0.2599 0.2 | Macoma mitchelli | 0.0736 | 0.0736 0.0736 0.0 | Marenzelleria viridis | 0.0368 | 0.0368 0.0368 0.0 | Tubificoides spp. | 0.0012 | 0.0012 0.0012 0.0 | Streblospio benedicti | 0.0012 | 0.0012 0.0012 0.0 | Chironomidae larvae | 0.0012 | 0.0012 0.0012 0.0 --------------------------------------------------------------------------------------------------------- | Biomass | 0.6589 |  | Biomass (w/o Epifauna) | 0.6589 |  ---------------------------------------------------------------------------------------------------------
 BOTTOM ENVIRONMENT AND BENTHOS, CHALK POINT OIL SPILL, SUMMER 2000

 ========================================================================================================= | Station: SC-23  | Location: Swanson’s Creek Habitat: Low Mesohaline Date: September 6 | Gear: Young Grab Sampled Area: 0.044 sq.m  ========================================================================================================= | BOTTOM ENVIRONMENT  ========================================================================================================= | Depth (m): Salinity (ppt): Temperature (C):  | Dissolved Oxygen (mg/l): Sediment Silt-Clay (%): 94.60 Total Carbon (%):  ========================================================================================================= | BENTHIC INDEX OF BIOTIC INTEGRITY  ========================================================================================================= | B-IBI Score: 1.00 Condition: Severely Degraded # Attributes Score | Value Score Va | Shannon-Weiner Index 0.00 1 Pollution Indicative Species Abundance (%) 100 | Abundance (#/m2) 23 1 Pollution Indicative Species Biomass (%) 100 | Biomass (g/m2) 0.00 1 Pollution Sensitive Species Abundance (%) 0 | Carnivore-Omnivore Abundance (%) 100.00 Pollution Sensitive Species Biomass (%) 0 | Deep Deposit Feeder Abundance (%) 0.00  ========================================================================================================= | BENTHIC ABUNDANCE (per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Coelotanypus spp. | 23 | 23.0 23  --------------------------------------------------------------------------------------------------------- | Number of Species | 1 |  | Number of Species (w/o Epifauna)| 1 |  | Abundance | 23 |  | Abundance (w/o Epifauna) | 23 |  ========================================================================================================= | BENTHIC BIOMASS (Grams per sq. meter)  ========================================================================================================= | | Rep 1 | Mean Std.Dev Min M --------------------------------------------------------------------------------------------------------- | Coelotanypus spp. | 0.0012 | 0.0012 0.0012 0.0 ---------------------------------------------------------------------------------------------------------

 | Biomass | 0.0012 | 

 | Biomass (w/o Epifauna) | 0.0012 | 

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