18

Mogelbexrg, D.D., B.F. Morris and J. Cadwaller. 1983. Sessile
fauna and flora. Bermuda Biol. Sta. Spec. Publ. 22:225-234.

Morgan, S.G., C.S. Manooch, III, D.L. Mason and J.W. Goy. 1985.

. Pelagic fish predation on Cerataspis, a vare larval genus of
ocenaic penaeoids. Bull. Mar. Sci. 36:249-259.

Morris, B.F., J. Cadwallader, J. Geiselman and J.N. Butler. 1976.
Transfer of petroleum and biogenic hydrocarbons in the
Sargassum community. Pages 235-259 in H.L. Windom and R,A. Duce
(eds.), Marine Pollutant Transfer. p.c. Heath and Co.
Lexington, MA.

Morris, B.F. and D.D. Mogelberg. 1973. Identification manual
to the pelagic Sargassum fauna. Bermuda Biol. Sta. Spec. Publ.
ll, 63 p.

Parr, A.D. 1939. Quantitative observations on the pelagic
Sargassum vegetation of the western North Atlantic. Bull.
Bingham Oceanogr. Coll., Yale Univ. 6(7):1-94.

Paul, V-J. 1987. Feeding deterrent effects of algal natural
preducts. Bull. Mar. Sci. 41:514-522.

Peres, J.M. 1982. Specific pelagic assemblages. Pages 314-372
in 0. Kinne (ed,), Marine Ecology, Vol. 5, pt. 1, John Wiley
and Sons, New York.

Phlips, E.J., M. Willis, and A. Verchick. 1986. Aspects of
nitrogen fixation in Sargassum communities off the coast of

Florida. J. Exp. Mar. Biol. Ecol. 102:99-119.


12

Literature Cited

Adams, J.A. 1960. A contribution to the biology and post-

‘larval development of the sargassum fish, Histrio histrio

Linnaeus), with a discussion of the Sargassum complex. Bull.
Mar. Sci. Gulf Carib. 10:55-82.

Beardsley, G.L., Jr. 1967. Age, growth, and reproduction of the
Golphin, Coryphaena hippurus, in the Straits of Florida. Copeia
1967:441-451.

Beebe, W. and J. Vee-Van. 1928. The fishes of Port~Au-Prince
Bay, Haiti. Zoologica 10:1~279.

Berry, F.H. 1959. Young jack crevalles (Carunx species) off
the southeastern Atlantic coast of the United States. Fish.
Bull., U.S. 59:417-535.

Berry, F.H. and L.E. Vogele. 1961. Filefishes (Monocanthidae)
of the western north Atlantic. Fish. Bull., U.S. 61:61-109.

Blake, N.J. and D.L. Johnson. 1976. Oxygen production-consumption
of the pelagic Sargassum community in a flow-through system with
arsenic additions. Deep-Sea Res. 23:773-778.

Bohlke, J.E. and C.C.G. Chaplin. 1968. Fishes of the Bahamas
and adjacent tropical waters. Livingston, Wynnewood, PA,
771 p.

Bortone, S.A.,; P.A. Hastings and S.B. Collard. 1977. The
pelagic Sargassum ichthyofauna of the eastern Gulf of Mexico.

Northeast Gulf Sci. 1:60-67.



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3

critical depth (~ 100 m) can withstand the hydrostatic pressure and
will ultimately rise to the surface. There is also, however, a
time-at-depth relationship that can influence the true critical
depth at which buoyancy is lost and the algae sink to the bottom
(Johnson and Richardson, 1977). Peres (1982) questioned the
ability of any sargassum to return to the surface after being
downwelled. When buoyancy is lost, sargassum sinks slowly to the
bottom (about 2 days to reach 5000 m) and provides a resource for
bottom dwelling consumers (Schoener and Rowe, 1970).

The contribution of sargassum to total primary production in
the western North Atlantic is variable and dependent on the region
examined and on accumulated biomass. Carpenter and Cox (1974)
estimated average production across the western Sargasso Sea at
1.0 mg c m“d', with higher values frequently occurring at
localities on the continental shelf and in the northern Sargasso
Sea (above 30°N). Howard and Menzies (1969) found production
highest in the Gulf Stream, lowest on the shelf, and intermediate
in the Sargasso Sea. These authors estimate sargassum probably
contributes about 0.5% of the total primary production in the
region, but nearly 60% of the total in the upper 1 m of the water
column (Howard and Menzies, 1969; Carpenter and Cox, 1974; Hanson,
1977; Peres, 1982). In addition, epiphytic cyanobacteria

(Dichothrix and Oscillatoriay contribute significantly to overall

production and nitrogen fixation within the immediate sargassum
community (Carpenter, 1972; Carpenter and Cox, 1974; Phlips and

Zeman, 1990). Both sargassum and its associated blue-green algae


19

Phlips, E.J. and C. Zeman. 1990. Photosynthesis, growth and
nitrogen fixation by epiphytic forms of filamentous
cyanobacteria from pelagic sargassum. Bull. Mar. Sci.

z 47:613-621.

Prescott, G.W. 1968. The algae: A review. Houghton Mifflin,
Boston, Mass., 436 p.

Randall, J.E. 1968. Caribbean reef fishes. T.F.H. Publications,
Inc., Jersey City, N.J. 318 p.

Robins, C.R., R.M. Bailey, C.E. Bond, J.R. Brooker, E.A.

Lachner, R.N. Lea, and W.B. Scott. 1991. Common and
scientific names of fishes from the United States and Canada,
Fifth edition. Am. Fish. Soc. Spec. Publ. 20, 183 p.

Ryland, J.S. 1974. Observations on some epibionts of gulf-weed,
Sargassum natans (L.) Meyen. J. Exp. Mar. Biol. Ecol. 14:17-25.

Ryther, J.M. 1956. The Sargasso Sea. Sci. Am. 194(1):98-104.

Schoener, A. and G.T. Rowe. 1970. Pelagic Sargassum and its
presence among the deep-sea benthos. Deep-Sea Res.
17:923-925.

Schwartz, F.J. 1988. Aggregations of young hatchling loggerhead
sea turtles in the sargassum off North Carolina. Mar. Turtle
Newsletter 42:9-10.

Schwartz, F.J. 1989. Biology and ecology of sea turtles
frequenting North Carolina. Pages 307-331, in R.Y. George and
A.W. Hulbert (ed.), North Carolina Coastal Oceanography

Symposium, NOAA-NURP Rep. 89-2.


25
Table 1. Contd.

Order Cyclopoida
Macrochiron avirostrum
M. hudsoni
M. sargassi
Copilia mediterranea

Order Thoracica
Conchoderma virgatum
Lepas anatifera
L. anserifera
L. australis
L. fascicularis
L. hilli
L. pectinata

Class Malacostraca
Order Decapoda

Alpheus sp.
Cerataspis monstrosa
C. petiti

Hippolyte coerulescens
H. ensiferus

H. tenuirostris

H. zoztericola
Latreutes ensiferus
L. fucorum

Leander tenuicornis
Palaemon natator

P. pelagicus

Planes minutus
Portunus sayi

P. spinimanus
Sergestes oculatus
Tozeuma carolinense
Virbius acuminatus

Order Isopoda
Anatanais normani
Bagatus minutus
Bopyroides latreuticola
Bopyrus squillarum
Idotea baltica
1. metallica
I. whymperi


21

Taylor, W.R. 1960. Marine algae of the eastern tropical and
subtropical coasts of the Americas. Univ. Mich. Press, Ann
Arbor, 870 p.

Teal, J. and M. Teal. 1975. The Sargasso Sea. Little, Brown,
Boston, MA, 216 p.

Trapnell, D., A.H. Knap and J.N. Butler. 1983. Hydrocarbons
in some fauna of the Sargassum community. Bermuda Biol. Sta.
Spec. Publ. 22:271-296.

Weis, J.S. 1968. Fauna associated with pelagic sargassum in
the Gulf Stream. Am. Midl. Nat. 80:554-558.

Winge, O. 1923. The Sargasso Sea, its boundaries and vegetation.
Rep. Dan. Oceanogr. Exped. 1908-1910 3(2): 3-34.

Winston, J.E. 1982. Drift plastic - an expanding niche for
a marine invertebrate? Mar. Pollut. Bull. 13:348-351.

Witham, R. 1988. Drifting Sargassum weed: safe haven or increased
risk for hatchling sea turtles? NOAA Tech. Memo. NMFS~SEFC-
214:129-130.

Woodcock, A.M. 1950. Subsurface pelagic Sargassum. J. Mar.
Res. 9:77-92.

Yeatman, H.C. 1962. The problem of dispersal of marine littoral
copepods in the Atlantic Ocean, including some redescriptions

of species. Crustaceana 4:253-272.


16

y, M.E. and W. Fenical. 1988. Marine Plant ~ herbivore
interactions: The ecology of chemical defense. Annu. Rev.
Ecol. Syst. 19:111-145.

Hay, M.E., P.E. Renaud and W. Fenical. 1988. Large mobile
yersus small sedimentary herbivores and their resistance to
seaweed chemical defenses. Oecologia 75:246-252.

Howard, K.L. and R.J. Menzies. 1969. Distribution and production
of Sargassum in the waters off the Carolina coast. Bot. Mar.
123244-254.

Hoyt, W.D. 1918. Marine algae of Beaufort, N.C., and adjacent
regions. Bull. U.S. Bur. Fish. 36:367-560.

Humm, H.d. 1979. The marine algae of virginia. Va- Inst. Mar.
Sci., Spec. Pap. Mar. Sci. No. 3.

Hurka, M. 1971. Factors influencing the gas composition in the
vesicles of Sargassum. Mar. Biol. 11:82-89.

Johnson, D.L. and R.S. Braman. 1975. The speciation of arsenic
and the content of germanium and mercury in members of the
pelagic Sargassum community. Deep-Sea Res. 22:503-507-

Johnson, D.L. and P.L. Richardson. 1977. On the wind-induced

sinking of Sargassum. J. Exp. Mar. Biol. Ecol. 28:255-267.

Kingsford, M.J3. 1990. Linear oceanographic features: a focus

for research on recruitment processes. Aust. J. Ecol.
15:391-401.
Kohlimeyer, J- 1971. Fungi from the Sargasso Sea. Mar. Biol

8:344-350.


8

Large predatory species associated with the sargassum habitat
include jacks, dolphins (Coryphaenidae), barracudas (Sphyraenidae) ,
mackerels and tunas (Scombridae), swordfish (Xiphiidae), and
billfishes (Istiophoridae) (Gibbs and Collette, 1959; Stephens,
1965; Dooley, 1972; Fedoryako, 1980; Carr, 1986; C. Manooch, pers.
somm.). It is believed that dolphin, a much sought after game and
feed fish, takes shelter under flatoam (including sargassum)
because cf the enhanced availability of prey (Dooley, 1972).
Filefish, triggerfish, jacks, flyingfish (Exocoetidae), and puffers
(Tetradontidae) are among the species identified in dolphin
stomachs (Gibbs and Collette, 1959; Dooley, 1972; Manooch et ale,
i984). Fragments of sargassum were also commonly found. Manooch
et al. (1984) stated "The close association (=dependence) of
dolphin with fish and invertebrates that form the sargassum

community is unmistakable". Manooch and Mason (1983) also reported

finding sargassum fragments in 26% of yellowfin tuna, Thunnus
albacaras, stomachs they examined as well as in 12% of blackfin tuna,

T. atlaniicus. They believed the material was ingested incidentally
with normal prey.

There is less known about the ichthyoplankton associated with
the habitat, but it seems likely that the same hydrodynamic
mechanisms that drive the formation of sargassum rafts, i.e.,
convergence of surface water within shear zones or Langmuir cells,
will also aggregate surface oriented organisms (Kingsford, 1990).

There is some evidence that this is the case for swordfish, Xiphias


31

Table 2 (Contd).

Scombridae
Acanthocybium solandri
Auxis thazard
Euthynnus alletteratus
Kaisuwonus pelamis
Scomber japonicus
Scomberomorus cavalla
Thunnus albacares
T. atlanticus

Xiphiidae
Xiphias gladius

Istiophoridae
Istiophorus platypterus
Makaira nigricans
Tetrapturus albidus

Stromateidae
Centrolophus sp.
Cubiceps pauciradiatus
Hyperoglyphe bythites
Hi. perciformis
Peprilus triacanthus
Psenes cyanophrys

Balistidae
Aluterus heudeloti
A, monoceros
A. schoepfi
A, scriptus
Balistes capriscus
Cantherhines macrocerus
C. pullus
Canthidermis maculata
C. sufflamen
Monacanthus ciliatus
M. hispidus
M. setifer
M. tuckeri
Xanthichthys ringens

Ostraciidae
Lactophrys sp.

* *

+b ee ee ee OF

wahoo

frigate mackerel
Little tunny
skipjack tuna
chub mackerel
king mackerel
yellowfin tuna
blackfin tuna

swordfish

sailfish
blue marlin
white marlin

ruff

bigeye cigarfish
black driftfish
barrelfish
butterfish
freckled driftfish

dotterel filefish
unicorn filefish
orange filefish
scrawled filefish
gray triggerfish
whitespotted filefish
orangespotted filefish
rough triggerfish
ocean triggerfish
fringed filefish
planehead filefish
slender filefish
pygmy filefish
sargassum triggerfish

boxfish


28

Table 2. Fishes associated with pelagic Sargassum in the North
Atlantic and Gulf of Mexico.® * = early life stage present
(i.e. egg, larvae or juvenile). Nomenclature follows
Robins et al. (1991).

Common Name

Carcharhinidae

Carcharhinus falciformis silky shark

C. limbatus blacktip shark

C. longimanus oceanic whitetip shark
Clupeidae

Sardinella aurita Spanish sardine
Gadidae

Urophycis earlli * Carolina hake

U. floridana * southern hake
Antennariidae

Histrio histrio * sargassumfish

Exocoetidae

Cypselurus furcatus spotfin flyingfish

C. melanurus * Atlantic flyingfish

Exocoetus obtusirostris * oceanic two-wing

flyingfish

Hemiramphus balao balao

H. brasiliensis ballyhoo

Hirundichthys affinis * fourwing flyingfish

Hyporhamphus unifasciatus silverstripe halfbeak

Parexocoetus brachypterus

Belonidae
Tylosurus acus

Fistulariidae
Fistularia tabacaria

sailfin flyingfish

agujon

bluespotted cornetfish

Centriscidae
Macroramphosus scolopax longspine snipefish
Syngnathidae
Hippocampus erectus * lined seahorse
H. reidi * longsnout seahorse
Microphis brachyurus * opposum pipefish
Syngnathus floridae * dusky pipefish
S. louisianae * chain pipefish _
S. pelagicus * sargassum pipefish
S. springeri * bull pipefish


5

shapes and coloration affording them the additional advantage of
camouflage among the floating plants. Others are less specialized
and utilize the habitat for foraging or protection from predators.
Community structure is variable; influenced by season, geographic
location, and algal "age" (Weis, 1968; Fine, 1970; Butler et al.
1983; Stoner and Greening, 1984). Weis (1968) also noted
differences in epibiont diversity between species of sargassum. —
an important factor in the structure of the community is related
to compounds occurring in the exudate released by the algae during
growth. Tannins produced on the distal growing tips of sargassum
have an inhibitory effect on colonizing epibionts (Conover and
Sieburth, 1964; Sieburth and Conover, 1965). This antifouling
effect lasts a short time and a succession of bacteria, hydroids,
bryozoans, and blue-green algae rapidly follow (Winge, 1923;
Conover and Sieburth, 1964; Ryland, 1974). Carpenter and Cox
(1974) also suggest that low epibiont density within some areas of
the Sargasso Sea may be nutrient limited rather than limited by the
antibiotic activity of sargassum exudates. Natural chemical
compounds, including phenolic compounds, produced by algae may also
serve as a deterrent to herbivores (Paul, 1987; Hay and Fenical,
1988; Hay et al., 1988; Steinberg, 1988).

For details of community metabolism, respiration, trophic web
and chemistry, we refer the reader to the works of Culliney (1970),
Burns and Teal (1973), Smith et al. (1973), Johnson and Braman
(1975), Blake and Johnson (1976), Hanson, (1977), Geiselman (1983),

Morris et al. (1976), and Trapnell et al. (1983).


4
epiphytes are adapted to conditions of strong sunlight, that is,
photosynthesis is not inhibited at high light intensities (Phlips,
et al., 1986).

é A survey conducted in the Sargasso Sea from 1933 to 1935
(Parr, 1939) estimated sargassum biomass at 524 to 1642 mg m?,
Stoner's (1983) estimates in the Sargasso Sea from the years 1977
to 1981 were less than 6% of those earlier estimates. He suggested
that the decline may have been anthropogenically influenced.
Subsequent analysis of Stoner's data, however, concluded that there
had been no significant change in the biomass of sargassum from
1933 to 1981, except in an area northeast of the Antilles. This
apparent decline was attributed to seasonal variation in sargassum
abundance or long-term current shifts, and apparently not to
pollution (Butler et al. 1983; Butler and Stoner, 1984). Reliable
estimates of total biomass are not available, however, as no
directed statistical study encompassing the vast range of these

species has been conducted.

Habitat Utilization
Pelagic sargassum supports a diverse community of marine
organisms including micro- and macro~epiphytes (Carpenter, 1970;
Carpenter and Cox, 1974; Mogelberg et al., 1983), fungi (Winge,
1923; Kohimeyer, 1971), more than 100 species of invertebrates
(Table 1), over 100 species of fishes (Table 2), and four species
ef sea turtles (Carr, 1987a; Manzella and Williams, 1991). Some

inhabitants, unique to the sargassum habitat, have evolved unusual


17
Langmuir, I. 1938. Surface motion of water induced by wind.
Science 87:119-123.
Manooch, C.S., III and W.T. Hogarth. 1983. Stomach contents
‘ and giant trematodes from wahoo, Acanthocybium solanderi, collected
along the south Atlantic and Gulf coasts of the United States.
Bull. Mar. Sci. 33:227-238.

Manooch, C.S., III and D.L. Mason. 1983. Comparative food of

yellowfin tuna, Thunnus albacares, and blackfin tuna, Thunnus

atlanticus, (Pisces: Scombridae) from the southeastern and Gulf
of Mexico coasts of the United States. Brimleyana 9:33-52.

Manocch, C.S., III, D.L. Mason and R.S. Nelson. 1984. Food and
gastrointestinal parasites of dolphin  Coryphaena_ hippurus
collected along the southeastern and Gulf coasts of the United
States. Bull. Jpn. Soc. Sci. Fish. 50:1511-1525.

Manooch, C.S., III, D.L. Mason and R.S. Nelson. 1985. Food of
little tunny Euthynnus alletteratus collected along the southeastern
and Gulf coasts of the United States. Bull. Jpn. Soc. Sci.
Fish. 51:1207-1218.

Manzella, S. and J. Williams. 1991. Juvenile head-started
Kemp's ridleys found in floating grass mats. Mar. Turtle
Newsletter 52:5-6.

Minerals Management Service. 1990. Final environmental report
on proposed exploratory drilling offshore North Carolina,
Vol. 1. U.S. Department of the Interior, Minerals Management
Service, Atlantic OCS Region. Environmental Assessment

Section, Herndon, VA.


7
et al. (1985) through stomach content analysis of several large
epipelagic predatory fishes. They found the large mysis of the
penaeoids, Cerataspis monstrosa and C. periti, frequently co-occurred with
sargassum in the stomachs of surface feeding tuna (Scombridae) and
dolphin Coryphaena hippurus. Nothing is known about the adult stage or

life history of these rare crustaceans.

Vertebrates - Fishes

There is a well known assemblage of small fishes associated
with sargassum rafts, many of which serve as forage for
commercially or recreationally exploited species (Table 2). Dooley
(1972) described 54 species from 23 families in the sargassum
community of the Florida Current, while Bortone et al. (1977)
reported 40 species from 15 families in the eastern Gulf of Mexico.
Only 14 species from 11 families are known from the Sargasso Sea
(Fedoryako, 1980; 1989).

Young jacks (Carangidae) live among the protective branches
of sargassum and feed heavily on copepods and larval decapods.
Apparently sargassum carries along a resident plankton population
capable of sustaining these voracious predators (Yeatman, 1962).
Sub-adult jacks range further from the rafts but dart in to feed
on shrimp and young fishes living in the sargassum. The filefishes
and triggerfishes (Balistidae) are also abundant and feed primarily
on hydroids, encrusting bryozoans, and other invertebrates.

Another major predator is the voracious sargassumfish, Histrio histrio,

which selectively preys upon shrimp and young fish (Adams, 1960).


23

Table 1. Invertebrates and primitive chordates associated with

pelagic Sargassum®. Taxonomy follows Brusca and Brusca
(1990).

Phylum Sarcomastigophora

Class Granuloreticulosea
Order Foraminiferida

Planorbulina acervalis
Rosalina sp.

Phylum Cnidaria

Class Hydrozoa
Order Hydroida

Aglaeophenia latecarinata
A, minuta

A. perpusilla

A, rigida

Aglaeophenoides mammillata

Antenella secundaria
Campanularia volubilis
Cladocryne pelagica
Clytia bicophora

C. cylindrica

C. johnstoni

C. longicyatha

C. noliformis

C. rarideniata

C. simplex
Desmocyphus pumilus
Dynamena quadridentata
Eucopella sargassicola
Gemmaria sp.
Gonothyraea gracilis
G. integra

Halecium nanum
Hebella calcarata
Laomedea sp.

Obelia bicuspidata

O. dichotoma

O. geniculata

Class Anthozoa
Order Actiniaria

Anemonia sargassensis

O. hyalina
Plumularia catharina
P. corrugata

P. diaphana

P. floridana

. Margaretta

. megalocephala

. obligua

. Sargassi

. Setaceoides

. Strictocarpa
Scandia mutabilis
Setularia amplectens
S. brevicyathus

S. cornicina

S. exigua

S. flowersi

S. gracilis
S. inflata
S.
5.

wrote

. mayeri

. rathbuni
S. stookeyi
S. turbinata
S. versluysi
Syncoryne mirabilis
Zanclea costata
Z. gemmosa


NOAA Technical Memorandum
NMES-SEFSC-296

x
‘ome

os

°C
% <
rene

UTILIZATION OF THE SARGASSUM HABITAT BY
MARINE INVERTEBRATES AND VERTEBRATES - A REVIEW

L. Coston-Clements, L.R. Settle, D.E. Hoss and F.A. Cross

October 1991

U.S. DEPARTMENT OF COMMERCE

Robert A. Mosbacher, Secretary

NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION

John A. Knauss, Administrator

NATIONAL MARINE FISHERIES SERVICE

William W. Fox, Jr. Assistant Administrator
for Fisheries

This Technical Memorandum series is used for documentation and timely
communication of preliminary results, interim reports, or similar special-purpose
information. Although the memoranda are not subject to complete formal review,

editorial control, or detailed editing, they are expected to reflect sound professional
work.


10

Hatchling turtles are thought to actively seek out frontal
zones and hence sargassum rafts. These areas are then utilized for
forage and protection during the "lost year" (Carr 1986; 1987a,b).
Witham (1988) suggested an alternative hypothesis for this
association. He noted that it remains untested as to whether sea
turtles actually benefit from their association with sargassum or
whether they are at increased risk from predation, entanglement,

and stranding.

Summary

The pelagic sargassum habitat of the northwestern Atlantic
consists of both truly pelagic forms and flotsom detached from
coastal regions. While within the neuston it provides numerous
species of invertebrates and vertebrates a source of food, shelter,
and substrate. Community structure varies with season, location,
and algal age.

While the relationship of many species within this habitat is
well understood, others remain less well known. This is
particularly true for egg and larval stages of fishes, some
crustaceans, and juvenile sea turtles. Functional relationships
between the animals and the habitat have not been elucidated (e.9.,
we do not know the effect of the loss of sargassum on fish or sea
turtle populations). Because estimates of oceanic biomass of
sargassum are variable and inadequate, we also do not have a clear

understanding the population dynamics of the sargassum habitat,


9
gladius, larvae and cobia, Rachycentron canadum, eggs near the Guif
Stream frontal zone (Hassler and Rainville, 1975; J.J. Govoni,
pers. comm.). In addition to feeding and shelter, adults of some
odeanic pelagic fishes use sargassum as a spawning substrate
(Dooley, 1972; Peres, 1982) or as a nursery area for larvae and
juveniles. Most notable among these are the flyingfishes (Winge,
1923; Breder, 1938) which are a major component of the diet of

large oceanic fishes.

Vertebrates-Sea Turtles

During the pelagic stage, hatchling loggerhead, Caretta caretta,
green, Chelonia mydas, Kemp's ridley, Lepidochelys kempi, and hawksbill,
Eretmochelys imbricata, sea turtles have been observed in sargassum off
Florida, Georgia, North Carolina, and Texas (Smith, 1968;
Fletemeyer, 1978; Carr and Meylan, 1980; Carr, 1986; 1987a;
Schwartz, 1988; 1989; Manzella and Williams, 1991; Schwartz, pers.
comm.). Hundreds of loggerhead hatchlings, both dead and alive,
were found in the wrack of sargassum deposited on the shore at
Cocoa Beach, Florida following a hurricane in September, 1979 (Carr
and Meylan, 1980). Stomach contents of the dead hatchlings showed
that almost all contained sargassum floats and leafy parts.
Schwartz (1988) reported numerous loggerhead hatchlings captured
during commercial trawling for sargassum. This observation
constitutes the largest known aggregation of loggerhead hatchlings

encountered off the North Carolina coast.


Table 2 (Contd).

Mullidae
Mullus auratus
Pseudupeneus maculatus
Upeneus parvus

‘ Kyphosidae
Kyphosus incisor
K. sectatrix

Chaetodontidae
Chaetodon ocellatus
C. striatus

Pomacentridae
Abudefduf saxatilis
A. taurus
Pomacentrus variabilis

Mugilidae
Mugil cephalus
M. curema

Sphyraenidae
Sphyraena barracuda
S. borealis

Polynemidae
Polydactylus virginicus

Labridae
Bodianus pulchellus
Thalassoma bifasciatum

Blenniidae
unidentified

Acanthuridae
Acanthurus randalli

Trichiuridae
Unidentified

30

*

red goatfish
spotted goatfish
dwarf goatfish

yellow chub
Bermuda chub

spotfin butterflyfish
banded butterflyfish

sergeant major
night sergent
cocoa damselfish

striped mullet
white mullet

great barracuda
northern sennet

barbu

spotfin hogfish
bluehead

blenny
gulf surgeonfish

snake mackerel


29
Table 2 (Contd).

Serranidae
Epinephelus inermis ~~

Priacanthidae
Pristigenys alta

Apogonidae
Apogon maculatus

Rachycentridae
Rachycentron canadum

Echeneidae
Phtheirichthys lineatus

Carangidae
Caranx bartholomaei
C. erysos
C. dentex
C. hippos
C. latus
C. ruber :
Chloroscombrus chrysurus
Decapterus macerellus
D. punctatus
D. tabl
Elagatis bipinnulata
Naucrates ductor
Seler crumenophthalmus
Seriola dumerili
S. fasciata
S. rivoliana
S. zonata
Trachurus lathami

Coryphaenidae
Coryphaena hippurus

Lutjanidae
Rhomboplites aurorubens

Lobotidae
Lobotes surinamensis

Sparidae
Pagrus pagrus

+e bb Re

+ bh et ee

marbled grouper

short bigeye

flamefish

cobia

slender suckerfish

yellow jack

blue runner
white trevally
crevalle jack
horse-eye jack
bar jack
Atlantic bumper
mackerel scad
round scad
redtail scad
Yainbow runner
pilotfish

bigeye scad
greater amberjack
lesser amberjack
almaco jack
banded rudderfish
rough scad

dolphin

vermilion snapper

tripletail

red porgy


Invertebrates

The invertebrate fauna consists of both sessile and motile
forms (Table 1). Epizoans include colonial hydroids, encrusting
bryozoans, the polychaete Spirorbis, barnacles, pycnogonids, and the
tunicate Diplosoma. Oider Plants gradually become heavily encrusted
with these organisms and uitimately sink. This biomass then
gxadually disintegrates, providing valuable nourishment for animals
in deeper water (Parr, 1939; Weis, 1968; Schcener and Rowe, 1970;
Butler et al. 1983). Conspicuous among the motile fauna are
decapoa crustaceans, particularly the Portunus crabs, and shrimps
Latreures and Leander, various molluscs, including the sargassum snail
Litiopa meianostoma, polychaetes, flatworms, and nudibranchs. Fine
(1970) found very high numbers of portunids in his late summer
samples in the Gulf Stream and Sargasso Sea. Only Portunus sayi is
commonly considered a resident of the community; the remaining
megalopa and juveniles are transitory and utilize the habitat as
a nursery.

Dooley (1972) examined stomach contents of the eight most
abundant fish species yielding further insight into the
invertebrate component of the sargassum community. These included
hydroids, copepods, phylosoma larvae, shrimp zoea and postlarvae,
crabs, pycnogonids, barnacles, tunicates, polychaetes, bivalves,
gastropods, and platyhelminthes. The presence of two rather

enigmatic members of the sargassum fauna were revealed by Morgan


20

Schwartz, F.3., W.T. Hogarth and M.P. Weinstein. 1982. Marine
and freshwater fishes of the Cape Fear Estuary, North
Carolina, and their distribution in relation to environmental
factors. Brimleyana 7:17-37.

Sieburth, J. McN. and J.T. Conover. 1965. Sargassum tannin,
an antibiotic which retards fouling. Nature 208:52-53.

Smith, K.L., Jr., K.A. Burns and E.J. Carpenter. 1973.
Respiration of the pelagic Sargassum community. Deep-Sea Res.
202213-217.

Smith, W.G. 1968. A neonate Atlantic loggerhead turtle,
Caretta caretla, captured at sea. Copeia 1968:880-881.

Steinberg, P.D. 1988. Effects of quantitative and qualitative
variation in phenolic compounds on feeding in three species
of marine invertebrate herbivores. J. Exp. Biol. Ecol.
126:221-237.

Stephens, W.M. 1965. Summer cruise to the Sargasso Sea. Sea
Frontiers 11:108-123.

Stommel, H. 1965. The Gulf Stream. Univ. Calif. Press, Berkeley,
248 p.

Stoner, A.W. 1983. Pelagic sargassum: evidence for a major
decrease in biomass. Deep-Sea Res. 30(4A) 3469-474.

Stoner, A.W. and H.S. Greening. 1984. Geographic variation
in the macrofaunal associates of pelagic Sargassum and some
biogeographic implications. Mar. Ecol. Prog. Ser.

20:185-192.


26

Table 1. Contd.

Janira minuta
Paradynamene benjamensis
Probopyrus latreuticola

Order Amphipoda
Ampithoe longimana
A. pelagica
Biancolina brassicaecephala
Caprella danilevskii
Hemiaegina minuta
Luconacia incerta
Sunampithoe pelagica
Vibilia pelagica

Phylum Tardigrada
Order Heterotardigrada

Styraconyx sargassi

Phylum Mollusca
Class Gastropoda
Order Mesogastropoda

Bittium sp.
Litiopa melanostoma
Rissoa sp.

Order Thecosomata
Creseis spinifera

Order Nudibranchia
Aeolidiella occidentalis
Corambella depressa
Cuthona pumilio
Doridella obscura
Doto pygmaea
Fiana pinnata
Glaucus atlanticus
Scyllaea pelagica
Spurilla sargassicola
S. neapolitana
Tethys protea

Class Cephalopoda
Order Teuthoida

Onychia caribaea


2
consider the pelagic forms a separate and distinct species group
having evolved from benthic species (Winge, 1923; Parr, 1939;
Friedrich, 1969; Butler et al., 1983; Stoner and Greening, 1984).
Supporting evidence includes the lack of sexual reproduction
characteristic of benthic forms, the loss of a basal holdfast, and
the number of endemic organisms in the associated community (10

invertebrates and 2 vertebrates). Benthic forms, such as 5S.

filipendula; occur in the open ocean in small quantities, but should
be considered flotsam (Hoyt, 1918; Winge, 1923; Parr, 1939; Dooley,
1972).

Sargassum circulates. between 20° and 40° N latitude and 30°W
longitude and the western edge of the Florida Current/Gulf Stream,
with an apparent center of distribution within the North Atlantic
Central Gyre between 28° and 34°N latitude (Fig. 1) (Winge 1923;
Ryther, 1956; Dooley, 1972; Butler et al. 1983). Large quantities
also occur on the continental shelf. Some of this material is cast
upon beaches along the eastern seaboard (Hoyt, 1918; Humm, 1979;
Winston, 1982), while much of it remains on the shelf or is
entrained into the Gulf Stream. Throughout the region, sargassum
frequently aggregates into large windrows in response to wind
forcing (Winge, 1923; Langmuir, 1938; Faller and Woodcock, 1964)
er shear currents along frontal boundaries (Stommel, 1965).
Woodcock (1950) demonstrated that sargassum can be downwelled along
such convergence zones; the depth of descent being dependent on the
buoyancy of individual algal clumps and the magnitude. of the

Langmuir circulation cell. Clumps that do not sink below a


13

Breder, C.M., Jr. 1938. A contribution to the life histories
of Atlantic Ocean flyingfishes. Bull. Bingham Oceanogr.
Coll., Yale Univ. 6(5):1-126.

Brusca, R.C. and G.J. Brusca. 1990. Invertebrates. Sinauer
Associates, Inc., Sunderland, MA. 922 p.

Burns, K.A. and J.M. Teal. 1973. Hydrocarbons in the pelagic
Sargassum community. Deep-Sea Res. 20:207-211.

Butler, J.N., B.F. Morris, J. Cadwaller and A.W. Stoner. 1983.
Studies of Sargassum and the Sargassum community. Bermuda Biol.
Sta. Spec. Publ. 22:1-85.

Butler, J.N. and A.W. Stoner. 1984. Pelagic Sargassum: has
its biomass changed in the last 50 years? Deep-Sea Res.
31:1259-1264.

Caldwell, D.K. 1959. Observations on tropical marine fishes
from the northeastern Gulf of Mexico. Quart. J. Fla. Acad.
Sci. 22:69-74.

Carpenter, E.J. 1970. Diatoms attached to floating Sargassum
in the western Sargasso Sea. Phycologia 9:271-274.

Carpenter, E.J. 1972. Nitrogen fixation by a blue-green
epiphyte on pelagic Sargassum. Science 178:1207-1209.

Carpenter, E.J. and J.L. Cox. 1974. Production of pelagic
Sargassum and a blue-green epiphyte in the western Sargasso Sea.
Limnol. Oceanogr. 19:429-435.

Carr, A. 1986. Rips, FADS, and little loggerheads. BioScience

36(2) 92-100.


15

Fedoryako, B.I. 1989. A comparative characteristic of oceanic

fish assemblages associated with floating debris. J.
é Ichthyol. 29(3):128-137.

Fine, M.L. 1970. Faunal variations on pelagic Sargassum. Mar.
Biol. 7:112-122.

Fletemeyer, J.R. 1978. Underwater tracking evidence of neonate
loggerhead sea turtles seeking shelter in drifting Sargassum.
Copeia 1978:148-149.

Friedrich, M. 1969. Marine biology. (Translated from German
by G. Vevers). Univ. Washington Press, Seattle, 474 p.

Geiselman, J. 1983. The food web of the Sargassum community.

Bermuda Biol. Sta. Spec. Publ. 22:260-270.

Gibbs, R.M., Jr. and B.B. Collette. 1959. On the identification,
distributions, and biology of the dolphins, Coryphaena hippurus
and C. equisetis. Bull. Mar. Sci. Gulf and Carib. 9:117-152.
Hanson, R.B. 1977. Pelagic Sargassum community metabolism -
carbon and nitrogen. J. Exp. Mar. Biol. Ecol. 29:107-118.
Hassler, W.W. and R.P. Rainville. 1975. Techniques for
hatching and rearing cobia, Rachycentron canadum, through larval

and juvenile stages. Univ. N.c., Sea Grant Publ. UNC-sG-
75-30.

Hastings, P.A. and S.A. Bortone. 1976. Additional notes on
tropical marine fishes in the northern Gulf of Mexico. Fla.

Sci. 39:123-125.


Introduction
Numerous species of brown algae (Class Cyclosporeae: Order
Fucales: Family Fucaceae) of the genus Sargassum occur throughout the
world's tropical and temperate oceans. The pelagic complex in the

wéstern North Atlantic is comprised primarily of Sargassum natans and

S. fluitans. Both species are hyponeustonic and fully adapted to a

pelagic existence (Parr, 1939). Known commonly as gulf-weed, sea
holly, or sargassum, they are characterized by a brushy, highly
branched thallus (stem) with numerous leaf-like blades and berry-
like pneumatocysts (floats). These floating plants may be up to
several meters in length but are typically much smaller. See Hoyt
(1918), Winge (1923), Parr (1939), Taylor (1960), Prescott (1968),
and Humm (1979) for detailed descriptions of the various species.

Sargassum floats contain mostly oxygen with some nitrogen and
carbon dioxide, and are responsible for buoyancy. Oxygen content
is dependent on the oxygen partial pressure of the surrounding
medium and independent of photosynthetic activity’ (Hurka, 1971).
Woodcock (1950) also found diurnal fluctuations in gas pressure
within the floats, and attributed it to similar changes in oxygen
partial pressure during daylight and darkness.

There is some debate as to whether sargassum found in the Gulf
Stream, Gulf of Mexico, Caribbean Sea, and the North Atlantic
Central Gyre is material detached from littoral plants in the
Antilles and other tropical regions during storms (Peres, 1982) or
whether the oceanic components are a separate species group

independent of their coastal littoral relatives. Most researchers


24

Table 1. Contd.

Phylum Platyhelminthes
Class Turbellaria
Order Acoela

Amphiscolopus sargassi

Order Polycladida
Acerotisa notulata
Holoplana grubei
Stylochus mertensi
S. pellucidus
Gnescioceros sargassicola

Phylum Annelida
Class Polychaeta
Order Phyllodocida
Alciope contrainii
Harmothoe dearborni
Platyneris coccinea
P. dumerillii

Order Sabellida
Spirorbis corrugatus

Order Amphinomida
Amphinome rostrata

Phylum Arthropoda
Class Pycnogonida
Anoplodactylus petiolatus
Endeis spinosa
Tanystylum orbiculaire

Class Branchiopoda
Order Cladocera

Evadne spinifera

Class Maxillopoda

Order Harpacticoida
Amonardia phyllopus
Dactylopodia tisboides
Harpacticus gurneyi
Paradactylopodia oculata
Paralaophonte congenera
Scutellidium longicauda


NOTICE:

The National Marine Fisheries Service (NMFS) does not approve, recommend or endorse any
proprietary product or proprietary material in this publication. No reference shall be made to NMFS,
nor to this publication furnished by NMFS, in any advertising or sales promotion which would indicate
or imply that NMFS approves, recommends or endorses any proprietary product or proprietary material
mentioned herein, or indirectly, the advertised product to be used or purchased because of this NMFS
publication.

This report should be cited as follows:

Coston-Clements, L., L.R. Settle, D.E. Hoss and F.A. Cross. 1991. Utilization of the
Sargassum habitat by marine invertebrates and vertebrates - a review. NOAA Technical
Memorandum NMFS-SEFSC-296, 32 p.

Copies may be obtained by writing:

National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161

or

National Marine Fisheries Service, NOAA
Southeast Fisheries Science Center
Beaufort Laboratory

101 Pivers Island Road

Beaufort, NC 28516-9722

Cover illustration from Teal and Teal, 1975.


32

Table 2 (Contd).

Fami Species Common Name
Tetraodontidae
Chilomycterus antennatus bridled burrfish
C. schoepfi striped burrfish
Diodon holocanthus *  ballonfish
D. hystric *. porcupinefish
Sphoeroides spp. * puffers
Molidae
Mola sp. sunfish

List compiled from: Beebe and Vee-Van, 1928; Breder, 1938;
Berry, 1959; Caldwell, 1959; Gibbs and Collette, 1959; Adams,
1960; Berry and Vogele, 1961; Dawson, 1962; Stephens, 1965;
Beardsley, 1967; Béhlke and Chaplin, 1968; Randall, 1968;
Weis, 1968; Friedrich, 1969; Fine, 1970; Dooley, 1972; Hassler
and Rainville, 1975; Teal and Teal, 1975; Hastings and
Bortone, 1976; Bortone et al., 1977; Fedoryako, 1980; Schwartz
et al., 1982; Manooch and Hogarth, 1983; Manooch and Mason,
1983; Manooch et al., 1984; Manooch et al., 1985; Carr, 1986;
Fedoryako, 1989; Minerals Management Service, 1990; J. Govoni,
pers. comm.; C. Manooch, pers. comm.; L. Settle, unpubl. data.


27
Table 1. Contd.

Phylum Ectoprocta
Class Gymnolaemata
Order Cheilostomata

Aetea anguina
Membranipora turberculata
Thalamoperella falcifera

Phylum Chordata
Class Ascidiacea
Order Aplousobranchia

Diplosoma gelatinosum

* List compiled from Winge,1923; Parr, 1939; Adams, 1960;
Yeatman, 1962; Weis, 1968; Friedrich, 1969; Fine, 1970; Dooley,
1972; Morris and Mogelberg, 1973; Ryland, 1974; Teal and Teal,
1975; Peres, 1982; Butler et al., 1983; Deason, 1983; Stoner and
Greening, 1984; and Morgan et al., 1985.


11
i.e., what is the standing crop, the productivity and the effect

of harvesting on living marine resources?

: Acknowledgments
We would like to express our thanks to Drs. J. J. Govoni and
F. Jd. Schwartz for providing unpublished data, Drs. W. W. Kirby-
Smith and R. E. Robbins for assistance with the invertebrate

taxonomy, and to Dr. C. S. Manooch, III for review of the report.

Personal Communications
Dr. J. J. Govoni, National Oceanic and Atmospheric Administration,
National Marine Fisheries Service, Southeast Fisheries Science

Center, Beaufort Laboratory, Beaufort, North Carolina, 28516.

Dr. CC. S. Manooch, III, National Oceanic and Atmospheric
Administration, National Marine Fisheries Service, Southeast
Fisheries Science Center, Beaufort Laboratory, Beaufort, North

Carolina, 28516.

Dr. F. J. Schwartz, University of North Carolina, Institute of
Marine Science, 3407 Arendell Street, Morehead City, North

Carolina, 28557.


14
cavr, A 19878 perspective on the pelagic stage of sea turtle
xx, A. °

development. Conserv: piol- 1(2)#103-121.

carr, A. 1987b. Impact of nondegradable marine debris on the
, A. .

A ecology and survival outlook of sea turtles. Mar. Pollut.
Bull. 18:352~-356.

carr, A. and A.B. Meylan 4980. Evidence of passive migration of
, Ao Be °

green turtle patchiings in Sargassum. Copeia 1980:366-368.

conover, J.T. and J. MeN gieburth. 1964. Effect of Sargassum
, oT. ° °

distribution on its epipiota and antibacterial activity. Bot.
Mar. 6:147-157.

culliney, J.L 1970 Measurements of reactive phosphorus
, Jobe .

associated with pelagic Sargassum in the northwest Sargasso Sea.

; »304-306-
Limnol. Oceanogr. 15130473

pawson, C.E. 1962. New records and notes on fishes from the
, CoE. :

north central culf of Mexico. Copeia 1962:442-444.

peason, E 1983 Meiofauna of pelagic Sargassum. Bermuda
, Ee .

2102-113.
Biol. Sta. Spec. Publ- 22:102-11

pocley, J.K 1972 Fishes associated with the pelagic sargassum
, o.K. °

. . sion of the sargassum community.
complex, with 4 discus $ y

Contrib. Mar. Sci- 16:1732-

paller, AJ. and A.H wooacock: 1964. The spacing of windrows
, A.J. oH.

of Sargassum in the 0ce@ J. Mar. Res. 22:22-29.

pedoryako, B.I 1980 qhe qchthyofauna of the surface waters of
; BI. .

the Sargasso sea gouthwest of Bermuda. J. Ichthyol.

20(4) :1-9-