• TABLE OF CONTENTS
HIDE
 Front Cover
 Title Page
 Table of Contents
 Introduction
 Methods
 Results
 Discussion
 Summary
 Recommendations
 References






Group Title: Technical paper -- Florida Sea Grant College Program ; no. 33
Title: Criteria for beach nourishment
CITATION PDF VIEWER PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00075985/00001
 Material Information
Title: Criteria for beach nourishment biological guidelines for sabellariid worm reef
Series Title: Technical paper Florida Sea Grant College
Physical Description: 34 p. : ill. ; 28 cm.
Language: English
Creator: Nelson, Walter G
Main, Martin B
Florida Sea Grant College
Publisher: Marine Advisory Program, Florida Cooperative Extension Service
Place of Publication: Gainesville Fla
Publication Date: 1985
 Subjects
Subject: Beach nourishment -- Florida   ( lcsh )
Reefs -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
bibliography   ( marcgt )
non-fiction   ( marcgt )
 Notes
Bibliography: Bibliography: p. 31-34.
Statement of Responsibility: Walter G. Nelson, Martin B. Main.
General Note: Grant NA80AA-D-00038.
Funding: This collection includes items related to Florida’s environments, ecosystems, and species. It includes the subcollections of Florida Cooperative Fish and Wildlife Research Unit project documents, the Florida Sea Grant technical series, the Florida Geological Survey series, the Howard T. Odum Center for Wetland technical reports, and other entities devoted to the study and preservation of Florida's natural resources.
 Record Information
Bibliographic ID: UF00075985
Volume ID: VID00001
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved, Board of Trustees of the University of Florida
Resource Identifier: oclc - 13188595

Downloads

This item has the following downloads:

PDF ( PDF )


Table of Contents
    Front Cover
        Front Cover
    Title Page
        Title Page
    Table of Contents
        Table of Contents
    Introduction
        Page 1
        Page 2
        Page 3
    Methods
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
    Results
        Page 9
        Page 10
        Page 11
        Page 12
        Page 13
        Page 14
        Page 15
        Page 16
        Page 17
        Page 18
        Page 19
        Page 20
        Page 21
        Page 22
    Discussion
        Page 23
        Page 24
        Page 25
        Page 26
        Page 27
    Summary
        Page 28
    Recommendations
        Page 29
        Page 30
    References
        Page 31
        Page 32
        Page 33
        Page 34
Full Text
/O0

j3
r.3


FILLE 6Ul


Criteria for Beach Nourishment:
Biological Guidelines
for Sabellariid Worm Reef


By Walter G. Nelson and Martin B. Main


FLORIDA SEA GRANT COLLEGE


TECHNICAL PAPER NO. 33




~I 'c ~


CRITERIA FOR BEACH NOURISHMENT: BIOLOGICAL GUIDELINES
FOR SABELLARIID WORM REEF





Walter G. Nelson
Martin B. Main




Department of Oceanography and Ocean Engineering
Florida Institute of Technology
Melbourne, Florida 32901





Project No. R/C-S-20
Grant No. NA80AA-D-00038




Technical Papers are duplicated in limited quantities for specialized
audiences requiring rapid access to information and may receive only
limited editing. This paper was compiled by the Florida Sea Grant College
with support from NOAA Office of Sea Grant, U.S. Department of Commerce,
grant number NA80AA-D-00038. It was published by the Sea Grant Extension
Program which functions as a component of the Florida Cooperative Extension
Service, John T. Woeste, Dean, in conducting Cooperative Extension work in
Agriculture, Home Economics, and Marine Sciences, State of Florida, U.S.
Department of Agriculture, U.S. Department of Commerce, and Boards of County
Commissioners, cooperating. Printed and distributed in furtherance of the
Acts of Congress of May 8 and June 14, 1914. The Florida Sea Grant College
is an Equal Employment Opportunity-Affirmative Action employer authorized
to provide research, educational information and other services only to
individuals and institutions that function without regard to race, color,
sex, or national origin.







TECHNICAL PAPER NO. 33
July 1985








TABLE OF CONTENTS


Page
Introduction 1


Methods 4
Burial Experiments 4
Siltation Experiment 6
Sulfide Toxicity Experiments 6
Sediment Analysis 7


Results 9
Burial Experiments 9
Siltation Experiment 9
Sulfide Toxicity Experiments 13
Sediment Analysis 13


Discussion 23
Burial Experiments 23
Siltation Experiment 24
Sulfide Toxicity Experiments 24
Sediment Analysis 26
Life History 27


Sumnary 28


Recommendations 29


References 31









INTRODUCTION

Beach nourishment is presently the method of choice in Florida
for combating severe erosion of beaches where valuable oceanfront prop-
erty is threatened. Numerous areas along the urbanized southeast and
southwest coasts of Florida where erosion problems exist also have
sabellariid worm communities, often associated with Anastasia
formation rock outcrops occurring in the surf zone. The Anastasia for-
mation, with beach rock outcrops, extends frcm Anastasia Island
opposite St. Augustine southward for 150 mi to Boca Raton. There it
grades into the Miami oolite formation. On the west coast, Anastasia
beach rock has been observed from a point north of Ten Thousand
Islands in Collier county to Siesta Key near Sarasota (Puri and
Vernon, 1964). Kirtley and Tanner (1968) identify 4 species of worm
of the family Sabellaridae in Florida and show a range distribution of
these species from Panama City east and south to Ten Thousand Islands
on the Gulf coast and from Amelia Island south to Daytona Beach Shores
and again frmn Cape Canaveral to Miami Beach on the east coast. Con-
cern over possible damage to these habitats has caused Florida Depart-
ment of Environmental Regulation to deny or delay the issue of permits
for beach re-nourishment and inlet sand-bypassing projects in areas
where worm camnunities are known to occur. However, only extremely
minimal information on biological parameters of these systems is avail-
able for decision making by state permitting agencies.
One of these worm species is of particular interest. Phragmata-
pcma lapidosa (Fig. 1) is known to create wave resistant reef
formations in the intertidal and shallow surf zones (1-4 m) along the
south coast of Florida from Cape Canaveral to Key Biscayne (Kirtley,
1966; Gram, 1968; Gore et al., 1978; Kirtley and Tanner, 1968;
Kreuger, 1974). These reefs act as anti-erosion agents by decreasing
wave action (Multer and Milliman, 1967), and possibly by trapping sand
from the littoral drift on the landward side of the reefs (Kirtley and
Tanner, 1968). An examination of coastal engineering aspects of worm
reefs by Mehta (1973) concluded that they were valuable in reducing
coastal erosion. Kirtley and Tanner (1968) report that the worm reef
in the intertidal area of south Florida's east coast appears to have a
direct relationship with beach rock and may aid in accumulation and
lithification of this material. Since the reef and beach rock have
high material strength, they are important factors in shoreline
development. In essence, these reef structures act as offshore
breakwaters. The reef orientation appears to be perpendicular to the
prevailing energy, as observed for the southeast trend of the Rio Mar
reef at Vero Beach which is perpendicular to the prevailing
northeasternly waves. Mehta (1973) suggests this orientation is
optimal for sand particle collection by the organisms.
In terms of its impact on sediment distribution, P. lapidosa
has been shown to selectively remove finer sand particles for use in
tubes, resulting in better sorting of beach sediments (Multer and
Milliman, 1967; Gram, 1968), while the reef structures can modify long-
shore transport (Mehta, 1973). These worms also use heavy minerals
and flat shell fragments in their tube building while cracks and
crevisses in the reef trap other sediment and shell material, result-
ing in a change in the sediment distribution pattern of the beaches
near reefs.

























































Illustration of Phragmatopoma lapidosa in its sand
grain tube. The worm on the left is shown in its feeding
position. The worm on the right is shown withdrawn into
its tube with the tube entrance blocked by modified setae
termed opercular palae. Redrawn from Kirtley, 1966.


Figure 1.











The ecological role of worm reefs in the near-shore environment
is largely unknown, although some work has been done on larval develop-
ment and settlement of the worms (Eckelbarger, 1976, 1978; Mauro,1975;
Kreuger, 1974). It is known that large numbers of species are associ-
ated with the worm reef structures (Gore et al., 1978; Van Montfrans,
1981; H. Rudolph, pers. comm.), significantly increasing species diver-
sity in the relatively species poor surf zone. Thus worm reefs can be
presumed to be important elements in the surf zone both from the bio-
logical and geological point of view, and concern over damage to these
systems is warranted.
In spite of the apparent importance of P. lapidosa reef struc-
tures, much basic information needed for making permit decisions is
lacking. Specifically, no information is available on the detrimental
effects of beach nourishment in the area of worm reefs. Information
on stress tolerance of P. lapidosa is limited to the studies of
Mulhern (1976) who has described acute oil toxicity for P.
lapidosa and Kavanaugh (1979) who has determined the effects of
cadmium on this species. No information for P. lapidosa is avail-
able on tolerances to sediment burial, siltation or exposure to hydro-
gen sulfide, all of which might occur during beach nourishment. This
is significant since Clark (1978) has described extensive mortality
among P. lapidosa following beach nourishment at Sebastian Inlet,
Florida, yet the precise cause of the mortality was not clearly determ-
ined and natural causes may have been responsible. For example,
little is known of th life span of P. lapidosa and it has been sug-
gested that worm reef colony life span may be as little as 3 months in
areas of active sand movement (T. Campbell, A. V. Strock & Assocs.,
pers. comm.).
It has been the purpose of this project to provide the basic
biological and geological data together with summary guidelines which
will allow Florida Dept. of Environmental Regulation and project
engineers to make necessary permitting and design decisions for beach
nourishment projects in worm reef areas. Towards this end, the
present work seeks to determine the tolerance of P. lapidosa to
sediment burial the tolerance of these organisms to exposure to
hydrogen sulfide, the tolerances of these organisms to heavy silt
loads in the water as well as sediment grain size utilization patterns
for this species.








METHODS
Iairge: ploct (- ol Ilvl.iy wurmn rooel' w!rc coL[htLocd l or each expor i-
ment from the north jetty at the Sebastian Inlet State Recreation Area
and transported in containers of seawater to the laboratory where they
were cut into blocks of approximately equal.size (5x5x8 cm). These
samples were immediately transferred to aquaria containing unfiltered,
aerated seawater and allowed to acclimate for 24 hours prior to an
experiment. Methodogies for individual experiments are described
below.
Procedures following each experiment were the same. Upon comple-
tion of a designated treatment, samples were placed in aerated aquaria
with unfiltered seawater and allowed a recovery period. Recovery per-
iods were of sufficient duration (one hr for the burial and siltation
experiments and 6 hrs for the sulfide experiments) to allow the worms
to begin actively pumping at the tube openings. Duplicate live counts
of worms were made for each sample, with recoil from touch by a
dissecting needle being the criterion used to indicate a living worm.
Samples were then fixed in a formalin/ rose bengal stain solution and
later disaggregated to obtain counts (heads only) of the total abundan-
ce of worms for each sample. Per cent survivorship of each sample was
determined from the ratio of the mean live count over the total abunda-
nce count from the disaggregated sample.
Percent survivorship data were transformed with the angular trans-
formation (arcsin square root) and inspected for compliance to assumpt-
ions of normality and homogeneity of variances by the Kolmogorov-Smirn-
ov test and the Fmax test, respectively. All experimental treat-
ments used three replicates. Analysis of variance (ANOVA) was utiliz-
ed in each case to determine the significance of treatment effects on
survival (Sokal & Rohlf, 1981), while the T-method for unplanned compa-
risons (Sokal & Rohlf, 1981) was used for comparisons of treatment
means.

Burial Experiments

Burial experiments tested the response of P. lapidosa to bur-
ial by five different sediment types over periods of 25, 48 and 72
hrs. The burial materials were beach sediments with grain size distri-
butions (Table 1) ranging from coarse to fine sediments (A, B, C, D),
as well as an estuarine muddy sand (E). The estuarine muddy sand was
similar in grain size distribution to the finest fraction of the beach
sediment (Table 1), but contained approximately twice the organic mat-
ter. All beach sediments were obtained from the ocean beach adjacent
to the laboratory and were wet sieved to obtain the appropriate size
classes. The estuarine muddy sand was collected from the Indian River
lagoon approximately one mile south of the Sebastian Inlet and was not
sieved. All sediments were allowed to air-dry prior to use, and sub-
samples of each material were analysed for grain size distribution.
Although separate collections of sediment were made for the February
and July experiments, Table 1 indicates that the grain size distribu-
tions of the treatments used in each experiment were basically sim-
ilar. The control consisted of worm reef blocks unexposed to sediment
burial. Burial experiments were conducted in February (1-4, 21-24)
and July (8-11), 1984. The first February experiment tested beach











Table 1. Grain size analysis of sediments used in the burial
experiments. Values are weight percent. Sediment types A,
B, C, D are sieved fractions of beach sand; type E is
unsieved estuarine sediment.


February Experiments
Sieve Size (mn)
Sediment Type 4 2 1 0.5 0.25 0.125 0.625


A 23.4 59.4 15.2 1.6
B 9.6 83.7 6.6 0.1
C 15.8 65.2 24.6 3.8 0.1
D 0.1 31.7 41.1 25.6
E 0.3 0.5 1.3 13.4 32.5 23.8 25.5


July Experiment
Sieve Size (mn)
Sediment Type 4 2 1 0.5 0.25 0.125 0.625


A 24.5 60.1 13.8 1.1 0.3 0.1 0.3
B 11.8 81.1 6.0 0.8 0.2 0.1
C 0.7 12.9 56.3 26.7 3.1 0.2
D 0.3 1.1 7.1 5.1 30.4 35.8 19.7
E 0.5 0.9 1.8 11.6 36.0 23.4 24.8






Table 2. Salinity and temperature fluctuations during the February and
July burial experiments.



Date Salinity (ppt) Temperature (OC)
Range Mean Range Mean


February 1-4 34-35 34.8 17.0-20.0 18.3

February 21-24 34-35 34.8 18.5-23.0 21.5

July 8-11 35-36 35.5 28.0-30.5 29.2








sediments A and D (Table 1), while the second tested sediment types C,
D and E. All five sediment types were tested simultaneously in the
July experiment. Studies were conducted in February and July to deter-
mine whether there might be seasonal differences in the response of
P. lapidosa to the burial treatments. Seawater in the tanks was
exchanged daily for fresh seawater transported directly from the
ocean.
Experimental design consisted of four 15 1 aquaria partitioned
into three sections with plexiglass dividers to assist in location of
sets of samples. Each section housed three samples of P. lapidosa
which were placed in a vertical orientation on a layer of beach sand.
All sections of the aquaria received aeration continuously during the
experiment. Burial treatment consisted of instantaneous burial to a
depth of approximately 18 cm (dictated by aquarium height) by a given
type of sediment. Salinity and water temperature were measured daily.

Siltation Experiment

The siltation experiment was designed to determine the mortality
of P. lapidosa in response to high concentrations of suspended
silt. Twelve replicate sample blocks of worm reef were placed in each
of four 15 1 aquaria. Blocks were held in place by a weighted wood
dowel framework to prevent damage to blocks resulting from the water
movement in the aquaria required to keep the silt in suspension. Silt
loads were added to the tanks by dry weight, with treatments consist-
ing of a control (no silt), 2.0, 4.0 and 6.0 g/l. The silt utilized
in these experiments was commercially available Fuller's earth (Fisher
No. F-90, technical grade). Fuller's earth is composed of attapulgite
and montmorillonite, two naturally occurring clays. The median grain
size of Fuller's earth is reported to be less than 0.0005 mm, and 82%
of the particles are less than 0.002 mm (O'Conner et al., 1977; Sherk
et al., 1976). Suspension of the silt was maintained by a continuous-
ly operating motor which propelled a single paddle in each tank at a
rate of 17 full strokes per minute. Turbidity levels were measured
daily by analysing water samples with a Hach 2100A Turbidimeter.
Three replicate samples of worm reef were removed from each of
the treatment tanks at intervals of 24, 48, 72 and 96 hrs. Salinity,
temperature and dissolved oxygen were recorded daily throughout the
experiment. The siltation experiment was performed from June 7-11,
1984.

Sulfide Toxicity Experiments

Two separate studies were performed, a preliminary 12 hr study
and a second 48 hr study. Experimental sulfide treatments were prepar-
ed using both deoxygenated and oxygenated seawater, using seawater
obtained from the region of the Gulf Stream. The seawater had first
been filterred with 0.3 micron glass fiber filters. Oxygen was strip-
ped from the seawater by bubling nitrogen through it. Dissolved
oxygen levels were measured with a YSI Model 57 Dissolved Oxygen meter
and oxygen probe which had been checked for accuracy with the Winkler
titration method. Dissolved oxygen levels were adjusted to <0.2 mg/l
and 6.0 mg/1 for the deoxygenated and oxygenated treatments, respectiv-
ely. Sulfide treatments were prepared according to general procedures










as outlined by Theede et al. (1969). Stock solutions were prepared by
dissolving 5 g of Na2S 9H20 per 1 with serial dilution to
appropriate experimental concentrations. A total of nine treatments
were tested in the preliminary 12 h study. These consisted of two
controls without sulfide addition (C = oxygenated seawater, N =
deoxygenated seawater), sulfide concentrations on the order of magnitu-
de of 10 M in both types of seawater (AS46= oxygenated, NS4 = deoxy-
genated), on the order of magnitude of 10 M in both types of sea-
water (AS6 oxygenated, NS6 = deoxygenated) and on the order of magni-
tude of 10 M in both types of seawater (AS9 oxygenatedd NS9 =
deoxygenated). The 48 hr study omitted the 10 M concentrations.
Concentrations of H S measured inhe stock solutions were 4.3 mg/l
and .048 mg/l for tIe 10 and 10 levels, respectively, for the
48 hr experiment.
Worm reef samples were placed into 0.95 1 glass jars containing
the treatment solutions and the jars were sealed with screw caps. In
both experiments, three replicates per treatment were used. All treat-
ments were analysed for sulfide content at the beginning and end of
the experiments by photometric procedures as described in Standard
Methods for the Examination of Water and Wastewater, 15th edition
(1980). Both experiments were conducted in the laboratory at 230 C
during December 1984.

Sediment Analysis

Samples of living worm reef were collected from six locations
along Florida's southeast coast. These locations were:

1. Bear Cut; Key Biscayne, Dade Co., (south side of channel).
2. Boynton Inlet; Palm Beach Co., (south beach).
3. Jupiter Inlet; Palm Beach Co., (north beach).
4. Fort Pierce Inlet; Indian River Co., (inside the inlet).
5. Vero Beach, St. Lucie Co., (pier piling, north Vero Beach).
6. Sebastian Inlet; Brevard Co. (north jetty).

Sample locations 1-3 were sampled August 25-26, 1984, locations 4-5 on
June 8, 1984, and location six on May 12 and November 2, 1984. Worm
reef samples were fixed in a formalin'-seawater solution for transporta-
tion to the laboratory where they were cut into three smaller samples
each approximately 5x5x5 cm in size. For each sample, the inner dia-
meter of the worm tube openings were measured with calipers fo5 25
individuals. Additionally, the number of tube openings per cm was
measured. Samples were then mechanically disaggregated and immersed
in chlorine bleach until all organic matter had been dissolved (Multer
& Milliman, 1967). These samples were then repeatedly washed with
distilled water, each time allowing the fine particles to settle
before decanting and repeating the procedure. Samples were dried at
900 C for at least 12 hrs, and then sieved using U. S. standard
sieves at 1 phi intervals. The calcium carbonate content was determin-
ed for each size class of sediment via acid digestion (Multer &
Milliman, 1967). Sediment samples were also taken from beaches
adjacent to the sites of the worm reef collections and were analysed
for grain size distribution and calcium carbonate content. To deter-
mine whether P. lapidosa selects certain grain sizes for tube








building, a concentration factor was computed as given by Multer &
Milliman (1967) and Scholl (1958). This factor is simply the ratio of
the weight percent in a given size class of worm reef sand to that of
the beach sand. A value greater than 1.0 indicates that the worm is
preferentially sorting sediment of this grain size from the beach sand
(Multer & Milliman, 1967). Mean and median grain sizes, sorting and
skewness (Innan, 1952) were averaged for the replicated samples from
each location.









RESULTS

Burial Experiments

Salinity data recorded during the burial experiments show little
fluctuation in salinity due to the daily changes of water in the
aquaria. Temperature regimes were considerably lower in the February
experiments than in the July study (Table 2).
The percent survival data for the burial experiments were analy-
zed using two-way ANOVA with replication. Analyses of the February
experiments indicate mortality was not significantly different among
sediment treatments in either experiment. A significant time effect
was present, however, in both of the February studies (Table 3), indic-
ating an increased mortality for all treatments the longer the animals
were held in the laboratory. The interaction term was non-significant
in both cases.
Different results were found for the single July experiment. As
in the February experiment, a significant increase in mortality over
time occurred. A highly significant effect due to sediment type was ob-
served, and the interaction of sediment type and duration of the exper-
iment was also significant (Table 4).
Graphical comparison of the group means using the T-method for un-
planned comparisons (Sokal & Rohlf, 1981) indicates that for the first
24 hrs, no significant differences in survival existed among the diffe-
rent sediment treatments, nor does survival differ significantly among
the controls over the 72 hr of the experiment (Fig. 2). Survival decr-
eases significantly after 48 hrs for all treatments where sediment was
added. After 72 hrs, the finer beach sediments (type D) and the estua-
rine muddy sand (E) caused the highest mortality of all treatments,
while that for the coarser sediments was not greatly different from
that for the 48 hr treatment. It is this disproportionate mortality
in the fine sediment treatments at 72 hrs which presumably gives rise
to the significant interaction term.

Siltation Experiment

For the siltation experiment, turbidity measurements were made at
the beginning of the experiment to obtain background turbidity levels
(initial), immediately after silt addition (t = 0), and daily for the
4 day duration of the experiment. Table 5 summarizes the turbidity
data. Background turbidity data resulted from the filling of the
aquaria with the seawater which had been transported from the surf
zone, an area where turbidity is generally high due to wave activity.
Background turbidity decreased with time in the control tank until 48
hrs, after which it remained relatively constant. In the silt addi-
tion treatments, the increased turbidities at 96 hrs versus 24 hrs
reflect increased sediment suspension as samples, which tended to
baffle the wave action, were removed from the aquaria. Salinity
remained constant throughout the experiment at 36 ppt. Temperatures
ranged from 26 26.80 C, while dissolved oxygen ranged from 5.9 -
6.0 mg/l.
The percent survival data from the siltation experiment were
analysed using a two-way ANOVA with replication (Table 6 ). Survival
was not significantly different among the silt treatments and no signi-









Table 3. Two-way analysis of variance results comparing percent
survivorship (arcsin square root transformed) anong treat-
for the two February burial experiments. Grain size distribu-
tions for the sediment types used are given in Table 1.



Experiment 1. Feb. 1-4, 1984.
Sediment treatments: control, A, D.
Time treatments: 25, 48, 72 hrs.

Source of Variation df Mean Square F Significance


Sediments 2 0.869 0.012 p>.05
Time 2 368.095 5.241 p<.05
Interaction 4 105.256 1.499 p>.05
Error 18 70.237


Experiment 2. Feb. 21-24, 1984.
Sediment treatments: control, B, C, E.
Time treatments: 25, 48, 72 hrs.

Source of Variation df Mean Square F Significance


Sediments 3 21.260 0.568 p>.05
Time 2 659.227 17.624 p<.05
Interaction 6 36.285 0.970 p>.05
Error 24 37.405



Table 4. Two-way analysis of variance results comparing percent
survivorship (arcsin square root transformed) anong treat-
ments for the July burial experiment. Grain size distribu-
tions for the sediment types used are given in Table 1.



July 8-11, 1984.
Sediment treatments: control, A, B, C, D, E.
Time treatments: 25, 48, 72 hrs.

Source of Variation df Mean Square F Significance


Sediments 5 1559.63 25.49 p<.001
Time 2 3490.55 57.05 p<.001
Interaction 10 380.57 6.22 p<.001
Error 36 61.18

























































S A B C D
c
0


Sediment Treatments (mm)


Figure 2.


Mean percent survivorship of Phragmatopoma lapidosa at
25, 48 and 72 hrs following burial by 5 different sediment
types for the July experiment. Grain size distributions
for each sediment type are given in Table 1.









Table 5. Turbidity data for the duration of the siltation experiment.
Data are nepholometric turbidity units (ntu).



Time Elapsed (hrs)
Treatment Initial 0 24 48 72 96


Control 20 23 12 6 5 6
2.0 g/l 37 1625 1150 1000 1200 1300
4.0 g/l 26 2625 1875 2062 2562 2875
6.0 g/l 24 3812 3000 3125 3562 3750




Table 6. Two-way analysis of variance results comparing percent
survivorship (arcsin square root transformed) among treat-
ments for the siltation experiment.



June 7-11, 1984.
Silt treatments: control, 6.0 g/l, 4.0 g/l, 2.0 g/l.
Time treatments: 24, 48, 72, 96 hrs.

Source of Variation df Mean Square F Significance


Silt 3 59.620 1.782 p>.05
Time 3 300.437 8.979 p<.001
Interaction 9 45.905 1.372 p>.05
Error 32 33.459



Table 7. One-way analysis of variance results comparing percent
survivorship (arcsin square root transformed) among treat-
ments for the 12 hr exposure to sulfide experiment.
Treatments listed below are described in the text.



December 3-4, 1984.
S-lfide treatments: C, N, AS4, NS4, AS6, NS6, AS9, NS9.

Source of Variation df Mean Square F Significance


Sulfide 7 38.542 1.837 p>.05
Error 16 20.976










ficant interaction effect was present. Survival of the organisms was
found to decrease significantly with time.

Sulfide Toxicity Experiments

Survival data fram the initial 12 hr study were analysed using
one-way ANOVA. ANOVA results indicate that for periods of up to 12
hrs, survival is not significantly affected by the sulfide treatments
tested (Table 7).
Survival data from the 48 hr experiment was analyzed with a
two-way ANOVA with replication, which indicated significantly differ-
ent effects on survival by the various treatments (Table 8). Mortal-
ity was shown to increase significantly over the duration of the exper-
iment. The interaction term of concentration of sulfide versus dura-
tion of exposure was also significant.
Comparison of the group means (T-method, Sokal & Rohlf, 1981) for
the first 24 hrs indicates that mean survival did not differ significa-
ntly among treatments (Fig. 3). After 48 hrs, the control treatments
(C,N) did not differ significantly from any of the 24 hr treatments,
while the treatments containing sulfide caused significantly greater
mortality than all but one of the 24 hr treatments. The treatment con-
taining the highest sulfide level together with deoxygenated seawater
(NS4) caused significantly greater mortality than all other treatments
after 48 hr (Fig. 3). The response of the worms in this treatment is
probably largely responsible for the significant interaction term
between sulfide concentration and duration of exposure.
Initial stock concentrations of 4.5 mg S/1 and 0.05 mg S/l were
used to prepare the 10 M and 10 M treatments, respectively (Fig.
4). Analysis of sulfide concentrations in experimental jars at 24 hrs
indicates that sulfide concentrations were generally below initial
concentrations, with the exception of the NS6 treatment. The reduc-
tion of sulfide concentrations is presumably the result of interaction
with oxygen either present in the water (AS6, AS4), or through oxygen
entering the jars over time (NS6, NS4). The rank order of sulfide con-
centrations at this time follows the order predicted based on treat-
ments, however. After 48 hrs, sulfides are present in jars of all
treatments at concentrations not related to original treatment levels,
indicating sulfide production in the jars was occurring at this point.


Sediment Analysis

Summary grain size statistics for sediments from worm tubes are
given in Table 9 while statistics for samples from the adjacent beach
are given in Table 10. Mean sediment grain size of worm reef sedi-
ments ranged from 1.3 1.83 phi (Table 9) as compared with a range of
0.33 2.87 phi (Table 10) from beach sediments. Worm reef samples
were all well to moderately sorted (Table 9). Beach sediments for
Jupiter Inlet and Fort Pierce Inlet were the only samples which were
poorly sorted (Table 10). No consistent pattern of skewness was seen
for either the worm reef or beach samples (Tables 9, 10).
Tables 11 and 12 give the complete size distribution data for
both the worm reef and beach samples. Figure 5 compares the mean and
median grain size for worm reef and beach samples. This figure indi-








Table 8. Two-way analysis of variance results comparing percent
survivorship (arcsin square root transformed) among treat-
ments for the 48 hr exposure to sulfide experiment.
Treatments listed below are described in the text.



December 17-19, 1984.
Sulfide treatments: C, N, AS4, NS4, AS6, NS6.
Time treatments: 24, 48 hrs.

Source of Variation df Mean Square F Significance


Sulfide 5 213.88 5.65 p<.05
Time 1 2409.41 83.46 p<.001
Interaction 5 163.10 7.41 p<.001
Error 24 28.87











Table 9. Summary statistics (phi units) for the analysis of sediment
derived from living worm reef.



Location Median Mean Sorting Skewness


Sebastian Inlet (5/12) 1.31 1.37 0.63 0.10
Sebastian Inlet (11/2) 1.15 1.30 0.69 0.22
Vero Beach 1.55 1.69 0.83 0.08
Fort Pierce Inlet 0.99 1.32 0.91 0.36
Jupiter Beach 1.78 1.83 0.62 0.08
Boynton Inlet 1.68 1.44 0.44 -0.55
Bear Cut 1.50 1.55 0.71 0.07














- C0


95-




70

85-
S24 h



75- 60

J,

> 65-



w 50 50

I z
uJ

40-


35-



25 30 24 h
048 h 48h




15 20 I I I I
C N AS6 NS6 AS4 NS4
SULFIDE TREATMENTS



Figure 3. Mean survivrship shown both as percent and as degrees
(arcsin square root transformed data) for Phragmatopoma
lapidosa at 24 and 48 hrs following exposure to H S. A
description of each treatment is given in the text.








stock
24 hour
48 hour


5.0-


4.0o 4


3.0O


2.0O


I.0O-


*ll


4 ~ I L


C N AS6 NS6 AS4

SULFIDE TREATMENTS


Figure 4.


Concentrations of H S at 24 and 48 hrs for each
treatment. Stock solution concentrations are also
indicated.


NS4


%- L


'












Sunmary statistics (phi units) for the
from beaches adjacent to worm reef.


analysis of sediment


location Median Mean Sorting Skewness


Sebastian Inlet (5/12) 1.48 1.37 0.77 -0.14
Sebastian Inlet (11/2) 0.72 0.68 0.68 -0.06
Vero Beach 1.94 2.05 0.75 0.15
Fort Pierce Inlet 0.30 0.33 1.06 0.03
Jupiter Beach 2.48 2.87 1.21 0.32
Boynton Inlet 2.51 2.50 0.38 -0.03
Bear Cut 1.11 1.04 0.69 -0.10









Table 17. Measurements of average inner diameter of tubes and
average tube density per cm for Phragmatopoma
lapidosa for locations along the southeast coast of
Florida.



Location Inner Diameter Std. Dev. Density2
(cm) (No./an)


Sebastian Inlet (5/12) 0.17 0.02 5.8
Sebastian Inlet (11/2) 0.18 0.01 4.4
Vero Beach 0.18 0.01 4.2
Fort Pierce inlet 0.20 0.01 2.8
Jupiter Beach 0.20 0.01 5.3
Boynton Inlet 0.21 0.01 4.8
Bear Cut 0.17 0.01 2.0


Table 10.







0.125-


















0.25


A
* 0


A A


0


BEACH SEDIMENTS

A mean grain size
* medium grain size

WORM REEF

A mean grain size
0 medium grain size


I I I I I I I


VI--
I--wj I
0-0
CO .OD


> D _J I
gZ

UW-
U,


CP
oo
Wuc;.
CO I
CO


z
2
<_J C\J

w -
U)


W1
a ,
(D


SAMPLING SITE AND DATE


Figure 5.


Comparison of mean and median grain size for %orm reef
sediment versus sediment from adjacent beaches for sample
sites along the southeast ooast of Florida.


3.00



2.75


2.50



2.25



2.00


A






0 i


0.50 -


1.75 -


1.50


1.25-



1.00 -


.75



.50



.25


.00 L


a)


-~--------'~-~-








Table 11. Size distribution of
weight percent.


sediment from worm reef samples.


Values are mean


Size Fraction (nm)
0.5 0.25 0.125


0.625 <0.625


Sebastian Inlet (5/12) -- -- 0.6 33.0 50.8 9.8 5.2 0.6
Sebastian Inlet (11/2) 0.1 0.2 0.9 42.4 41.0 10.4 4.0 1.0
Vero Beach -- 0.1 1.0 21.2 52.1 16.2 7.5 1.9
Fort Pierce Inlet -- 0.1 4.0 46.1 31.6 9.2 7.8 1.2
Jupiter Beach -- -- 0.1 8.3 59.5 27.2 2.3 2.6
Boynton Inlet -- -- 0.4 15.5 53.2 28.2 2.3 0.4
Bear Cut -- 0.2 0.9 22.5 54.2 19.0 0.9 2.4






Table 12. Size distribution of sediment from beach samples. Values are nean
weight percent.



Size Fraction (nm)
Location 4.0 2.0 1.0 0.5 0.25 0.125 0.625 <0.625


Sebastian Inlet (5/12) --- 0.8 5.6 18.8 52.5 22.0 0.1 0.4
Sebastian Inlet (11/2) -- 0.8 15.2 48.5 33.7 1.7 0.1 --
Vero Beach -- 0.5 15.7 5.3 43.0 39.0 10.5 -
Fort Pierce Inlet 4.2 6.7 26.1 39.7 16.4 4.6 2.4 0.1
Jupiter Beach -- 0.1 0.4 4.2 21.1 49.8 1.2 23.3
Boynton Inlet -- -- 0.1 0.9 8.4 82.3 8.0 0.2
Bear Cut -- 0.8 6.2 33.5 51.7 7.7 -- -


Location








Concentration factors (weigth % worm
each sediment size fraction.


reef / weight % beach sand) for


Size Fraction (rrn)
Location 4.0 2.0 1.0 0.5 0.25 0.125 0.625 <0.625


Sebastian Inlet (5/12) --- 0.0 0.1 1.8 1.0 0.5 86.7 1.7
Sebastian Inlet (11/2) -- 0.2 0.1 0.9 1.2 6.0 36.4 48.5
Vero Beach -- 0.3 0.1 4.0 1.2 0.4 0.7 9.4
Fort Pierce Inlet -- 0.0 0.2 1.2 1.9 2.0 3.3 23.8
Jupiter Beach -- 0.2 0.2 2.0 2.8 0.6 1.9 0.1
Boynton Inlet --- 0.3 4.4 17.2 6.3 0.3 0.3 1.7
Bear Cut --- 0.3 0.1 0.7 1.1 2.5 28.7 118.0






Table 14. Mean percent carbonate for each sediment size fraction for the worm
reef sediment.



Size Fraction (mn)
Location 4.0 2.0 1.0 0.5 0.25 0.125 0.625 <0.625


Sebastian Inlet (5/12) -- 90.0 96.4 96.2 93.2 64.9 19.3 20.5
Sebastian Inlet (11/2) 90.7 81.3 95.8 96.8 92.8 72.3 19.3 16.6
Vero Beach -- 100 95.6 81.5 77.0 76.4 23.4 15.8
Fort Pierce Inlet -- 58.3 98.9 93.0 89.0 70.4 18.4 25.2
Jupiter Beach -- 100 92.3 88.3 84.5 85.5 59.2 64.6
Boynton Inlet -- 100 91.4 91.7 93.3 87.1 58.6 80.7
Bear Cut -- 33.3 92.3 88.3 84.5 85.5 59.2 64.6


Table 13.








Table 15. Mean percent carbonate for each sediment size fraction for the beach
samples.



Size Fraction (mn)
Location 4.0 2.0 1.0 0.5 0.25 0.125 0.625 <0.625


Sebastian Inlet (5/12) -- 99.6 93.8 59.3 24.8 20.4 8.4 13.5
Sebastian Inlet (11/2) -- 99.1 94.0 59.2 26.8 21.5 20.0 66.7
Vero Beach -- 99.6 98.4 71.7 25.1 20.5 8.2 10.3
Fort Pierce Inlet 99.3 96.7 70.9 38.0 27.0 9.6 11.4
Jupiter Beach -- 100 69.0 89.1 54.7 35.6 9.7 15.7
Boynton Inlet -- 100 94.3 -74.3 40.9 36.8 18.6 10.5
Bear Cut -- 100 69.0 89.1 54.7 35.6 9.7 15.7






Table 16. Concentration factors for carbonate (weigth % worm reef / weight %
beach sand) for each sediment size fraction.



Size Fraction (mn)
Location 4.0 2.0 1.0 0.5 0.25 0.125 0.625 <0.625


Sebastian Inlet (5/12) -- 0.9 1.0 1.6 3.8 3.2 2.3 1.5
Sebastian Inlet (11/2) -- 0.8 1.1 1.6 3.3 3.2 0.9 0.4
Vero Beach -- 1.0 1.0 1.1 3.1 3.7 2.9 1.5
Fort Pierce Inlet -- 0.6 1.0 1.3 2.3 2.6 1.9 2.2
Jupiter Beach -- 1.0 1.3 1.0 1.5 2.4 6.1 4.1
Boynton Inlet -- 1.0 1.0 1.2 2.3 2.1 3.2 7.7
Bear Cut -- 0.3 1.3 1.0 1.5 2.4 6.1 4.1









cates that the mean grain size selected by the worms fell in a conside-
rably smaller range (0.5 0.25 am) than that for the beach sediments
(0.84 0.125 mm). On beaches with relatively coarse sands (Fort
Pierce, Sebastian Inlet 11-2, Bear Cut) the worms concentrated finer
sand fractions relative to the beach sand. On beaches with finer
sands (Jupiter, Boynton, Vero Beach), the worms tended to concentrate
coarser size fractions relative to the beach sediment. Concentration
factors for all sediment size classes are given in Table 13, and con-
firm the relationship suggested by Fig. 5. At all sites except
Jupiter Beach, which had the finest mean grain size sediments of the
locations sampled the worms concentrated particles less than 0.063
nm.
The mean percent of carbonate, an indication of shell material,
is given for each size class for the worm reef samples (Table 14) and
the beach samples (Table 15). Percentage carbonate decreased with
decreasing grain size for both types of samples. Table 16 gives the
concentration factor for carbonate in each size fraction, indicating a
tendency for the worms to concentrate carbonate fractions in most
cases in the finer grain sizes.
The mean inner diameter of worm reef tubes ranged from 0.17 -
0.21 mm (Table 17). The mean number of tubes per cm ranged from
2.0 5.8 (Table 17).










DISCUSSION

Burial Experiments

The response patterns of Phraqmatopoma lapidosa to the types
of environmental disturbance which might be associated with beach nour-
ishment are variable depending on the nature of the stress and the
physical environmental conditions in which the stress is applied. For
example, the results of the burial experiment indicate that P.
lapidosa can tolerate burial by any of the tested sediment types for
up to 25 hours without suffering significantly increased mortality.
At relatively cooler temperatures (17 23 o C), burial by any of the
sediment types results in no significant increase in mortality rela-
tive to controls for up to 72 hrs. However, at warmer temperatures
(28 310 C), significantly increased mortality occurs after 48 hrs
for all sediment types. At higher temperatures, mortality due to
burial by fine sediments was greatly increased. The statistical
analysis suggests the presence of a synergistic interaction between
fine sediment size and duration of burial which is particularly harm-
ful at higher water temperatures.
Water temperature may influence survivorship in several ways.
Firstly, solubility of oxygen in seawater is less at higher tempera-
tures (Riley & Skirrow, 1965). Secondly, respiratory demands will be
greater at higher temperatures, and it has been noted for a variety of
marine organisms that mortality is increased at low oxygen levels when
temperature is high (Vernberg & Vernberg, 1972). The decrease in poro-
sity of fine sediments (Rhoads, 1974) would result in more rapid
oxygen depletion than in fine sediments. Increased bacterial action
at high temperature may also be a contributing factor. Once anoxic
conditions in the sediment become established, bacterial break-down of
organic material may lead to formation of sulfides and H S, which
are often highly toxic to organisms (Theede et al., 1969 In the sum-
mer burial experiments, the presence of sulfides was qualitatively
noted, especially in the fine sediment treatments after 72 hrs. It is
probable, therefore, that the synergistic effect on mortality observed
was due to increased toxic sulfide production in the fine sediment
treatments together with the decreased oxygen availability of these
sediments.
Mauer et al. (1978, 1981a, 1981b, 1982) examined the responses to
burial of several burrowing polychaetes as well as several species of
bivalves and crustaceans. They found that that temperature did not
have a clear effect on mortality, but rather influenced the percentage
of animals which migrated upward through the sediment. Upward
migration through sediment overburden appears to reduce mortality for
many of organisms tested which have been tested (Mauer et al., 1978,
1981a, 1981b, 1982; Chang & Levings, 1978). Since Phragmatopcma
lapidosa is a sessile tube dweller, it will be unable to migrate
upward through the sediment.
Taylor & Littler (1982) have reported on the tolerance to burial
of a congener of Phragmatopama lapidosa, Phragmatopoma
californica. They found that burial for 5 days in the laboratory at
16' C resulted in mortality in excess of 95%. Field studies of P.
californica in a sand-influenced, rocky intertidal area indicated
decreases in worm cover which resulted from sand burial. Taylor &








Littler (1982) concluded that P. californica is relatively intoler-
ant of burial as compared with such species as the anemone
Anthopleura elegantissima which can survive burial for up to three
months.

Siltation Experiment

High concentrations of silt in the water column resulting from
dredging, beach nourishment or even natural storm run off events can
negatively affect aquatic organisms. These effects may be either
sub-lethal (O'Conner et al., 1977; Sherk et al., 1976) or lethal
(O'Conner et al., 1976). Sessile organisms may be particularly sensit-
ive to silt in the water because of their inability to move elsewhere
to avoid it. Corals, for example, have been shown to be sensitive to
the presence of silt resulting from dredging (Hudson, 1981; Bak, 1978)
and beach nourishment (Wershoven & Wershoven, 1984). Phragmatopoma
lapidosa, however, showed no indication of a negative response over
a four day period of exposure to extremely high silt levels. Experime-
ntal turbidities were 2 orders of magnitude greater than maximum
levels reported from surf zones from either the west or east coast of
Florida (Pinellas County, 31 JTU, Saloman & Naughton, 1979; Sebastian
Inlet beach, 50 NTU, D. K. Stauble, Dept. of Oceanography & Ocean
Engineering, Florida Institute of Technology, unpub. data). Silt
loads were comparable to that measured in the immediate vicinity of a
dredge discharge or that of a flood-stage river (O'Conner et al.,
1976). The presence of high silt loads in the water column do not
appear detrimental to P. lapidosa adults as long as the silt does
not bury the worms. In high energy beach situations, silt tends to be
rapidly removed from the beach nourishment sand and dispersed in the
long-shore drift system (Stauble et al., 1983). Should physical condi-
tions not disperse the silt from the near-shore zone, burial of worm
reef and subsequent mortality, as indicated by the results of the
burial experiments, might follow. This condition was observed follow-
ing beach nourishment in the Pompano Beach Lauderdale-by-the-Sea
area with resultant damage to coral (Wershoven & Wershoven, 1984).
Despite the apparent tolerance of adults to high silt loads, the
tolerance of larval stages or newly settled individuals to this stress
remains unknown.

Sulfide Toxicity Experiments

The presence of sulfides and H2S are generally correlated with
a lack of oxygen and often occur in poorly oxygenated, muddy substra-
tes. Theede et al. (1969) have shown that tolerance to sulfides is
correlated with tolerance to low oxygen conditions and that species
from mud bottom substrates are generally more tolerant than those from
hard or sandy bottoms. Given this relation, it would be expected that
P. lapidosa, which occurs in well oxygenated areas might be relati-
vely intolerant of the presence of sulfides. At the highest sulfide
concentration in oxygen deficient seawater (4.2 mg/1), 50% mortality
of P. lapidosa occurred at between 24 and 48 hrs. Only 3 of 14
species, all of them crustaceans, tested by Theede et al. (1969)
possessed a lower tolerance than P. lapidosa, suggesting that
indeed it may be relatively sensitive to sulfides.










Mortality of P. lapidosa in the high sulfide concentration
treatment with oxygenated water after 48 hrs was significantly less
than for the same treatment of sulfide in deoxygenated water. This is
because the presence of oxygen immediately began to decrease the conce-
ntration of sulfide, which was confirmed by the measurement after 24
hrs of sulfide concentrations in these treatments. Mortality in the
oxygenated, high sulfide treatment (AS4) after 24 hrs was about 20%,
while sulfide concentration had dropped from 4.25 to 0.8 mg/l.
Interpretation of this sulfide exposure experiment is complicated
by the fact that sulfide production occurred in the jars of all
treatments during the experiment. This can be seen as early as the 24
hour sample where decomposition rate calculations (see below) would
predict only 0.016 mg/1 H2S given the initial concentration for
treatment AS4, while a mean of 0.82 mg/l was actually found. Part of
this difference may be the slightly lower temperature of the
experiment (23" C) versus that for the rate constant (250 C)
determination, but sulfide production was clearly seen in all
treatments at 48 hrs. At that time, observed sulfide levels were no
longer related to initial treatment concentrations. It is certainly
clear that from measured sulfide levels, treatment NS4 experienced the
highest level of exposure for at least the first 24 hrs, and it was
indeed this treatment which experienced the greatest mortality after
48 hrs. Other treatments which became exposed to sulfide only after
24 hrs (the controls: C, N) certainly had a lower total duration of
exposure.
Extrapolating the results of the laboratory sulfide experiments
to a field situation where beach nourishment is taking place is
difficult. That sulfides can be present during such projects is indic-
ated by a report from a beach nourishment project in North Carolina
where estuarine sediments were dredged and placed on the beach (Reilly
& Bellis, 1979, 1983) and H2S was qualitatively detected. Theede et
al. (1969) suggest values up to 6-7 mg/l of sulfides may not be uncom-
mon for mud bottoms. However, in the presence of oxygen, sulfide oxid-
ises to sulphate if oxygen concentration is high, or first produces
intermediate compounds such as sulphur, sulphite, thiosulphate and
tetrathionate if oxygen concentration is relatively low (Richards,
1965). In the near shore habitats of P. lapidosa the seawater
should be saturated with oxygen. At 25^ C in oxygen-saturated
seawater, approximately 1 mg/l of HS takes 30 hours for complete
oxidation of sulfides (Richards, 1965). At lower oxygen concentra-
tions, the reaction is slowed considerably, with only half of the
sulfides being oxidised in 60 hours. Low temperatures also consider-
ably slow the reaction, with the reaction at 6.50 C being 4 times
slower than at 250 C.
Use of the rate constant given by Richards (1965) allows calcula-
tion of the half life of sulfides by the formula

(1) k = .693 / t
.5
where k is the rate constant equal to 0.23/hr at 250 C and t is
the half-life. With the half-life, it is possible to estimate the
quantity of H2S at any time given some initial concentration of









H2S using the formula

(2) qt = q0 (5)t/t5

where q, is the quantity of H2S at time t and q0 is the initial
concentration of H2S. Assuming water with H2S at 6 mg/l entered
the surf zone and was uniformly mixed with wter saturated with oxygen
at 250 C, the concentration of HS at 12 hours would be only 0.38
mg/1. It would fall to only 0.02 mg/1 at 24 hours, and would be essen-
tially 0 by 48 hours. This suggests that for a single event introduc-
ing H2S into its environment, if P. lapidosa can survive expo-
sure to H S for 24 hours, then minimal damage should subsequently
occur. T? results of the sulfide exposure experiments after 24 hrs
suggest no significantly increased mortality to P. lapidosa occurr-
ed in this time frame.
Decreased temperature would decrease the decomposition rate of
sulfides. Using the rate constant given by Richards (1965) for 6.50
C., an initial concentration of 6 mg/1 would leave 2.8, 1.3, and 0.28
mg/1 at 12, 24 and 48 hours, respectively. This could potentially
increase the mortality of P. lapidosa, although the role of temper-
ature in influencing mortality in response to sulfide exposures is not
ccnpletely known. Theede et al. (1969) found that isolated invertebr-
ate tissue survived combined sulfide exposure and oxygen deficiency
better at colder temperatures.

Sediment Analysis

The sedimentary characteristics of worm tubes of the family
Sabellariidae have been previously examined for Sabellaria
vulgaris by Rees (1976), for Phragmatopoma californica by Scholl
(1958), and for Phragmatopoma lapidosa by Kirtley (1966), Multer &
Milliman (1967), and Gram (1968). Sedimentary analyses in the present
study generally confirm the conclusions of these previous studies.
P. lapidosa tends to remove the relatively finer sands from the
beach sediments as indicated by Multer & Milliman (1967) and Gram
(1968). In all samples except that from the Jupiter Inlet area,
concentration of sediments smaller than 0.0625 nm was indicated. The
Jupiter Inlet beach had the finest sediments of all sites sampled.
However, for the entire sediment distribution, mean grain size for
worm reef was greater than that for beach sand at three locations and
less than that for beach sand at three locations. This pattern
reflects the tendency of P. lapidosa to utilize a limited size
range of sand grains for its tubes. Multer & Milliman (1967) found
this size range to be mainly between 0.5 and 0.125 mm, which was
confirmed in the present broader survey of sites in southeast Florida.
Multer & Milliman (1967) suggest the concentration of particles
smaller than 0.0625 mm is due to the use of these particles as mortar
between larger sand grains. The present study also found that worms
tend to concentrate CaOD in the form of shell fragments in their
tubes as was found by Multer & Milliman (1967) and Gram (1968).
The suggestion of Gram (1968) that removal of finer sediments by
P. lapidosa results in an improved sorting of beach sediments is
not supported by the present data. Of seven sample occasions, beach
sediment was better sorted in 3 cases, less well sorted in 3 cases,










and equal in sorting in one case. Examination of the data of Multer &
Milliman (1967) also fails to support Gram's proposal as a general
case.

Life History

Field studies of the sabellariid Phragmatopcma californica
(Taylor & Littler, 1982; Littler et al., 1983) have suggested that
this species has an opportunistic life history strategy. This conclu-
sion is based on the continuous occurrence of viable gametes and the
continuous presence of larvae in the plankton which allow it to rapid-
ly colonize space trade available by unpredictable disturbances. In
contrast to many opportunistic species, P. californica can resist
invasion by other species and persist in areas of low disturbance. In
areas receiving periodic stress (sand-burial), P. californica can
establish colonies, but mortality from the stress prevents persistence
of the colonies.
Ecklebarger (1976) has shown that P. lapidosa also carry sex
products during all months of the year, although actual presence of
larvae in the plankton and larval settlement occurred in only a few
months of the year. Ecklebarger (1976) concluded that spawning could
be a year-round event. Larval developmental characteristics of P.
lapidosa are very similar to those of P. californica
(Ecklebarger, 1977). Ecklebarger (1976) also notes the susceptibility
of P. lapidosa colonies to temperature stress which resulted in a
die-off of intertidal colonies in the Seminole Shores, Florida area.
Observation of P. lapidosa colonies in inshore areas near Ocean
Ridge, Florida found the worm colonies to be patchily distributed,
with an average life span of three months, due to sand movement (T. J.
Campbell, A. V. Strock & Assoc., pers. comrn.).
The similarities between P. californica and P. lapidosa
are suggestive that the later species may also be a basically opportun-
istic species which can persist for considerable periods in benign hab-
itats but which may be frequently removed in more physically variable
areas by natural causes, particularly temperature stress and burial by
sand.









SUMMARY


The results of experiments designed to test the tolerance of
Phragmatopma lapidosa to stresses which might result from beach
nourishment are summarized below.

1) Phragmatopoma lapidosa appears tolerant of very high
silt loads and can tolerate silt levels 100 times natural
levels for at least four days without increased mortality.

2) Phragmatopoma lapidosa can tolerate burial by
sediment for only 24 hrs at summer temperatures. This
species may tolerate burial for at least 72 hrs at cooler
winter temperatures.

3) Burial with finer sediments results in significantly
increased mortality as compared with coarser sediments,
presumably due to the decreased porosity of the fine
sediments which limits oxygen transport through pore water.

4) Phragmatopoma lapidosa does not appear particularly
well adapted to surviving burial, but may instead use an
opportunistic larval strategy which allows recolonization of
areas which have been buried and re-exposed.

5) Phragmatopoma lapidosa appears able to tolerate
exposure to sulfides for 24 hrs at levels likely to be
released in a single exposure event. Repeated exposure
which results in continuous exposure to sulfides at levels
in the mg/1 range may result in considerable mortality.

6) Phragmatopana lapidosa does not appear particularly
sensitive to the grain size composition of beach sediments
since it occurs adjacent to beaches with a wide range of
mean grain sizes. The worm's ability to select the grain
sizes which it requires, primarily in the range 0.5 0.125
mm, which is a range present on most beaches, would allow it
to occur in most sandy areas where hard substrate for attach-
ment also occurs.










RECOMMENDATIONS


1) Use of reducing sediments containing H2S as beach fill
material should be avoided. Oxidation of sulfides is rapid
in oxygenated water, but continuous sediment pumping opera-
tions might result in exposure to sulfides beyond the toler-
ance of the animals.

2) Fill placement would be preferable during cool water
periods because of the increased period of time that burial
could be survived.

3) The presence of fine sediments in beach fill which may
result in siltation does not appear to be of major concern
with regard to Phragmatopoma lapidosa, as long as the
silt does not completely bury the organisms. It should be
recognized that other organisms associated with beach rock
outcrops whose tolerances have not been determined may be
less tolerant of suspended silt.

4) In areas slated for beach nourishment, mapping of inter-
tidal and subtidal rock outcrops and estimation of percent
coverage of Phragmatopoma lapidosa should be carried out
prior to beach nourishment. Presence of beach rock or other
hard substrate is necessary for establishment of worm
colonies, but is not evidence that worm colonies are indeed
present. Given the probable life history pattern of P.
lapidosa, most colonies may be ephemeral, and the presence
of significant coverage should be verified before nourish-
ment projects are redesigned or denied because of specific
concerns over worm reef. In many cases, the outcroppings
which are close inshore may be frequently buried by sand
naturally and may support only temporary communities of
organisms.

5) While it appears that Phragmatopoma lapidosa adults
may be able to tolerate to a degree some of the stresses
associated with beach nourishment, additional information on
the species would be highly beneficial. Confirmation of the
presumed opportunistic strategy of P. lapidosa is need-
ed. More extensive observations of the seasonality of lar-
val presence in the plankton and of larval settlement are
desirable. Evaluation of the tolerances of larvae and newly
settled individuals to beach nourishment stresses would
allow determination of whether effects on larvae present a
potential problem.

6) It must be remembered that although Phragmatcpama lapidosa
may tolerate the stresses of beach nourishment to same degree,
the diverse group of organisms associated with worm reef may be
more sensitive. No data for the tolerances of these associated
organisms is now available. Also, even where Phragmatopoma
lapidosa is absent, there is often an extensive hard bottom
community whose composition, ecology, and tolerance to stress is
29








virtually unknown. A cautious approach is advisable until these
data gaps are filled.








REFERENCES

Bak, R. P. M. 1978. Lethal and sublethal effects of dredging on reef
corals. Mar. Poll. Bull. 9:14-16.

Chang, B. D. & C. D. Levings. 1978. Effects of burial on the heart
cockle Clinocardium nuttallii and the Dungeness crab Cancer
magister. Estuar. Coast. Mar. Sci. 7:409-412.

Clark, K.B. 1978. Summary of monitoring of seagrasses and sabellarid
worm-reefs at Sebastian Inlet Florida. II. Post dredging report.
Unpublished report to the Sebastian Inlet Tax District
Commission.

Eckelbarger, K.J. 1976. Larval development and population aspects of
the reef-building polychaete Phragmatopoma lapidosa from the
east coast of Florida. Bull. Mar. Sci. 26:117-132.

Eckelbarger, K.J. 1977. Larval development of Sabellaria
floridensis from Florida and Phragmatopama californica from
southern California (Polychaeta:Sabellariidae), with a key to the
sabellariid larvae of Florida, and a review of development in the
family. Bull. Mar. Sci. 27:241-255.

Eckelbarger, K.J. 1978. Metamorphosis and settlement in the
Sabellariidae. In: Chia, F. and Rice, M. eds., Settlement and
Metamorphosis of Marine Larvae, pp. 145-164. Elsevier, New York.

Gore, R.H., L.E. Scotto & L. J. Becker. 1978. Camrunity composition,
stability, and trophic partitioning in decapod crustaceans
inhabiting some subtropical sabellariid worm reefs. Bull. Mar.
Sci. 28:221-248.

Gram, R. 1968. A Florida sabellariid reef and its effect on
sedimentary distribution. J. Sed. Petr. 38:863-868.

Hudson, J. H. 1981. Growth rates in Montastraea annularis: a
record of environmental change in Key Largo Coral Reef Sanctuary,
Florida. Bull. Mar. Sci. 31:444-459.

Inman, D. L. 1952. Measures for describing the size distribution of
sediments. J. Sed. Petr. 22:125-145.

Kavanaugh, B. A. 1779. The effects of cadmium on the reef-forming
sabellariid polychaete Phragmatopcma lapidosa. M. S. thesis,
Florida Institute of Technology, Melbourne, Fl. pp 51.

Kirtley, D.W. 1966. Intertidal reefs of sabellariidae (Annelida,
Polychaeta) along the coast of Florida. Masters thesis. Florida
State University, Tallahassee.

Kirtley, D. W. 1967. Worm reefs as related to beach stabilization.
Shore and Beach 35:31-34.


31


VII- I'8-,_~ U-- ,,. ---







Kirtley. D.W. 1968. The reef builders. Natural History. 77:40-55.

Kirtley, D.W. 1974. Geological Society of America annual meeting,
Miami Beach, Floirda, November 18-20, 1974. Unpublished field
guide.

Kirtley, D.W. and W. F. Tanner. 1968. Sabellariid worms: builders of a
major reef type. J. Sed. Petr. 38:73-78.

Kreuger, P.J. 1974. Transplantation and settling studies concerning
the sabellariid Phragmatopama lapidosa onto artificial
concrete substrates. Masters thesis. Florida Institute of
Technology, Melbourne Fl. pp. 72.

Littler, M. M., D. R. Martz & D. S. Littler. 1983. Effects of
recurrent sand deposition on rocky intertidal organisms:
importance of substrate heterogeneity in a fluctuating
environment. Mar. Ecol. Prog. Ser. 11:129-139.

Mauro, N.A. 1975. The premetamorphic development rate of
Phragmatopama lapidosa Kinberg, 1867, compared with that in
temperate sabellariids (Polychaeta:Sabellariidae). Bull. Mar.
Sci. 25:387-392.

Maurer, D. R. T. Keck, J. C. Tinsman, W. A. Leathem, C. A. Wethe, M.
Huntzinger, C. Lord & T. M. Church. 1978. Vertical migration of
benthos in simulated dredged material overburdens. Vol. 1. Marine
benthos. U. S. Army Engineers Waterways Experimental Station,
Tech. Rept. D-78-35, 1-97.

Maurer, D. R., T. Keck, J. C. Tinsman & W. A. Leathem. 1981a. Vertical
migration and mortality of benthos in dredged material part I:
mollusca. Mar. Env. Res. 4:299-319.

Maurer, D. R., T. Keck, J. C. Tinsman & W. A. Leather. 1981b. Vertical
migration and mortality of benthos in dredged material part II:
crustacea. Mar. Env. Res. 5:301-317.

Maurer, D. R., T. Keck, J. C. Tinsman & W. A. Leathem. 1982. Vertical
migration and mortality of benthos in dredged material part
III: polychaeta. Mar. Env. Res. 6:49-68.

Mehta, A.J. 1973. Coastal engineering study of sabellariid reefs:
Report of hydraulic model study to the Harbor Branch Foundation
Laboratory, Ft. Pierce, Fl. Gainesville, Coastal and
Oceanographic Engineering Lab, Eng. and Indust. Exper. Sta.,
Univ. Florida. 67p.

Mulhern, E. 1976. A toxicity study of three refined fuel oils and a
reference toxicant with respect to the sabellariid worm
Phramatopama lapidosa. Masters thesis. Florida Institute of
Technology, Melbourne, Fl. pp. 45.









Multer, H. G. & T. D. Milliman. 1967. Geologic aspects of sabellariid
reefs in southeastern Florida. Bull. Mar. Sci. 17:257-267.

O'Conner, J. M., D. A. Neumann & J. A. Sherk, Jr. 1976. Lethal effects
of suspended sediments on estuarine fish. U. S. Army Corps of
Engineers, Coastal Engineering Research Center, Tech. Pap. 76-20.

O'Conner, J. M., D. A. Newmann & J. A. Sherk, Jr. 1977. Sublethal
effects of suspended sediments on estuarine fish. U. S. Army
Corps of Engineers, Coastal Engineering Research Center, Tech.
Pap. 77-3.

Puri, H. S. & N. O. Vernon. 1964. Summary of the geology of Florida
and a guidebook to the classic exposures. Special Publ. #5.
Florida Geol. Survey. pp. 312.

Rees, C. P. 1976. Sand grain size distribution in tubes of
Sabellaria vulgaris Verill. Chesapeake Sci. 17:59-61.

Rhoads, D. C. 1974. Organism-sediment relations on the muddy sea
floor. In: H. Barnes, ed. Oceanography and Marine Biology: an
Annual Review. Vol. 12, pp. 263-300. London, Allen & Unwin.

Reilly, F. J., Jr. & V. J. Bellis. 1978. A study of the ecological
impact of beach noursihment with dredged materials on the
intertidal zone. East Carolina Univ. Inst. for Coast. & Mar.
Resources Tech. Rept. No. 4. pp. 107.

Reilly, F. J., Jr. & V. J. Bellis. 1983. The ecological impact of
beach nourishment with dredged materials on the intertidal zone
at Bogue Banks, North Carolina. U. S. Army Corps of Engineers,
Coastal Engineering Research Center, Misc. Rept. 83-3.

Richards, F. A. 1965. Anoxic basins and fjords. In:Riley J. P. & G.
Skirrow, eds. Chemical Oceanography. Vol. 1. Academic Press, New
York. pp. 712.

Riley J. P. & G. Skirrow, eds. 1965. Chemical oceanography. Vol. 1.
Academic Press, New York. pp. 712.

Salaman, C. H. & S. P. Naughton. 1979. Fishes of the littoral zone,
Pinellas County, Florida. Florida Sci. 42:85-93.

Scholl, D. W. 1958. Effects of an arenaceous tube-building polychaete
upon the sorting of a beach sand at Abalone Cove, California.
Compass Magazine, 35:276-283.

Sherk, J. A., Jr., J. M. O'Conner & D. A. Neumann. 1976. Effects of
suspended solids on selected estuarine plankton. U. S. Army Corps
of Engineers, Coastal Engineering Research Center, Misc. Rept.
76-1.

Sokal, R. R. & F. J. Rohlf. 1981. Biometry. W. H. Freeman, San
Francisco, pp. 859.


--?~C~-~*l-l~l*--*rCII11









Stauble, D. K., M. E. Hansen, R. L. Hushla & L. E. Parson. 1983.
Biological and physical monitoring of beach erosion control
project, Indialantic/Melbourne Beach, Florida. Part I: Physical
monitoring. Unpublished report to the U. S. Army Corps of
Engineers, Jacksonville District.

Taylor, P. R. & M. M. Littler. 1982. The roles of ccnpensatory
mortality, physical disturbance, and substrate retention in the
development and organization of a sand-influenced, rocky
intertidal ccamunity. Ecology 63:135-146.

Theede, H., A. Panat, K. Hiroki & C. Schlieper. 1969. Studies on the
resistance of marine bottom invertebrates to oxygen-deficiency
and hydrogen sulfide. Mar. Biol. 2:325-337.

Van Montfrans, J. 1981. Decapod crustaceans associated with worm rock
(Phramatcpcma lapidosa Kinberg)'in southeastern Florida.
Masters thesis. Florida Atlantic University, Boca Raton, Fl. pp.
290.

Vernberg, W. B. & F. J. Vernberg. 1972. Environmental Physiology of
Marine Animals. Springer-Verlag, New York, pp. 346.

Wershoven, R. & Wershoven, J. 1984. Pampano Beach Lauderdale-by-the
Sea beach nourishment project and its effects on the coral reefs.
Unpublished rept. to the Broward County Environmental Quality
Control Board.




University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs