(DRAFT) - Taxonomy
Species searobin, northern
Species Id M010501
Date 26 AUG 96
TAXONOMY
NAME - searobin, northern
OTHER COMMON NAMES - web-fingered searobin, grunter, cuckoo-fish, common gurnard, red-winged searobin, pigfish, flying-fish, flying-toad, american gurnard, searobin, robin and green-eyes
ELEMENT CODE -
CATEGORY - Fish
PHYLUM AND SUBPHYLUM - Vertebrata,
CLASS AND SUBCLASS - Teleostomi, Actinopterygii
ORDER AND SUBORDER - Perciformes, Cottoidei
FAMILY AND SUBFAMILY - Trigidae, Triglini, Peristediini
GENUS AND SUBGENUS - Prionotus,
SPECIES AND SSP - carolinus,
SCIENTIFIC NAME - Prionotus carolinus
AUTHORITY - Linnaeus
TAXONOMY REFERENCES - 180
COMMENTS ON TAXONOMY -
Although Trigla was the first genus used in classification of searobins from
American waters, today it is not a recognized genus for North American
searobins but rather the European counterpart to the American genus
Prionotus. Trigla was first used by Linnaeus, after Artedi, in his tenth
edition of Systema Naturae (1758-1759), in which binomial nomenclature has
its recognized beginning. Prionotus was first used by Lacepede in his
"Histoire Naturelle des Poissons" (1798-1803).
Objective synonymy:
Trigla palmipes
Mitchill, 1814, Trans. Lit. Philos. Soc. N.Y. 1: 431, pl. 4, fig.5 (New
York Harbor).
Prionotus pilatus
Storer, 1848, Proc. Boston Soc. Nat. Hist. 2: 77 (Mass. Bay).
Storer, 1846, "Synopsis, 270, 1846".
Storer, 1867, Hist. Fish. Mass. p. 68, pl. 6, fig 1 (Mass. Bay).
Gill, 1873, Cat. Fish East Coast N. Am. p. 21 (name only).
Goode and Bean, 1879, Bull. Essex Inst. p. 12.
Prionotus palmipes
Storer, 1867, Hist. Fish. Mass., p. 66, pl. 5, fig. 1 (Tisbury, Mass.).
Jordan and Gilbert, 1883b, Proc. U.S. Nat. Mus. P. 614.
Jordan and Gilbert, 1883c, Synop. Fish. N. Am. p. 734.
Jordan, 1887b, Cat. Fish. N. A., p. 114 (name only).
Goode, 1885, Nat. Hist. Aquatic Animals, p. 255, pl. 71 (Beesley's Point,
N.J.).
Taxonomy - 1 (DRAFT) - Taxonomy
Species searobin, northern
Species Id M010501
Date 26 AUG 96
Prionotus affinis
Hildebrand and Schroeder, 1928, Bull. U.S. Bur. Fish. 43(1): 315, fig. 188
(off Kent Island, Md. and Old Point Comfort, Va.).
Taxonomic status:
The northern searobin was originally classified as Trigla carolina in 1771.
Since then the genus has changed to Prionotus and several species names have
been used. The first review of the genus was made in 1887 by Jordan and
Hughes in which the name Prionotus carolinus was used. With the exception
of Hildebrand and Schroeder (1928) who called it Prionotus affinis, the name
Prionotus carolinus has been accepted since 1887.
Standard common names, vernacular names:
The standard common name adapted by the American Fisheries Society is
northern searobin. Vernacular names include: web-fingered searobin,
grunter, cuckoo-fish, common gurnard, red-winged searobin, pigfish,
flying-fish, flying-toad, American gurnard, searobin, robin, green-eyes.
Members of the family Triglidae are often referred to as "gurnards" (akin to
French "grogner"-to grunt, growl, grumble) because of the grunting sound
they emit. They should not be confused with the "flying gurnard" (family
Dactylopteridae, genus Dactylopterus). The only other fish sometimes
referred to as gurnard is Callionymus draco. According to one source,
"gurnard" is the European terminology and "searobin" American *180*.
Taxonomy - 2 (DRAFT) - Status
Species searobin, northern
Species Id M010501
Date 26 AUG 96
STATUS
Coded Status
Sport Fish
See Comments
REFERENCES FOR STATUS - 180
COMMENTS ON STATUS -
Sport fishery - Searobins are good fighters and they are comparable in
quality to a kingfish or whiting as food. Dispite this, they are generally
considered a nuisance to most fisherman as they are spiny to handle and
there is relatively little of them that can be eaten.
Commercial fishery - Searobins are considered trash fish and are taken
incidentally with the food fish catch or with the trash fish catch *180*.
Status - 1 (DRAFT) - Distribution
Species searobin, northern
Species Id M010501
Date 26 AUG 96
DISTRIBUTION
Distribution - 1 HABITAT ASSOCIATIONS
NATIONAL WETLAND INVENTORY CODES
NWI NWICLS NWIMOD NWISPEC
Marine BB2 V 1
Marine BB2 V 1
Estuarine FL2 V 1
Estuarine FL2 V 1
Marine BB2 V 1
Marine BB2 V 1
REFERENCES FOR NWI - 180
COMMENTS ON HABITAT ASSOCIATIONS -
Northern searobins can be found from the estuaries to the edge of the
continental shelf and they prefer a sandy bottom. They tend to keep to the
bottom but swim actively and are sometimes caught close to the surface.
Studies show that the larvae are found over the entire width of the
continental shelf from New York to Cape Hatteras, North Carolina.
Juveniles are regularly mixed with adults in ocean surveys. Few are
reported in estuarine surveys. Adult and juvenile searobins north of Cape
Hatteras migrate from mid-shelf and far-shelf waters inshore into the Long
Island, New York area in April. In May they are found inshore from Block
Island, Rhode Island to Cape Hatteras and they remain there until
September when a few start migrating to mid-shelf waters again. South of
Cape Hatteras northern searobin appear to be scattered over the shelf most
of the year although there are no summer data available *180*.
Habitat Associations - 1 (DRAFT) - Food Habits
Species searobin, northern
Species Id M010501
Date 26 AUG 96
FOOD HABITS
TROPHIC LEVEL -
CARNIVORE
REFERENCES FOR TROPHIC LEVEL - 180
LIFESTAGE FOOD FOOD PART
General Annelids Not Specified
General Crustaceans Not Specified
General Bivalve Molluscs Not Specified
General Squid, Octopus Not Specified
General Clupeiformes Not Specified
General Pleuronectiformes Not Specified
Adult Clupeiformes Not Specified
Adult Annelids Not Specified
Adult Bivalve Molluscs Not Specified
Adult Clupeiformes Not Specified
Adult Pleuronectiformes Not Specified
Adult Crustaceans Not Specified
Juvenile Copepods Not Specified
REFERENCES FOR GENERAL FOOD - 180
REFERENCES FOR ADULT FOOD - 180
REFERENCES FOR JUVENILE FOOD - 180
COMMENTS ON FOOD -
Stomachs and intestines of this species have yielded a variety of material.
In one specimen were found a young herring, several young clams, two shrimp,
and a pebble. Small specimens have yielded shrimp in large numbers,
amphipods and other small crustaceans, squid and lamellibranch mollusks,
annelids, and seaweed. Another source listed shrimp, crabs, amphipods,
squid, bivalve mollusks, annelid worms, small fish (i.e. herring, menhaden,
winter flounder), seaweed, and any bait *180*.
COMMENTS ON ADULT FOOD -
The major diet items of older fish are Mysis americana (Mysidacea), Gammarus
locusta (Amphipoda) and/or various other amphipods, depending on location.
(Decapoda), various annelids, cumacean, gastropods, pelecypods, fish, and
eggs along with sand and seaweed were consumed in small amounts *180*.
COMMENTS ON JUVENILE FOOD -
While copepods were eaten in large quantities by young-of-the-year northern
searobin from the Woods Hole, Massachusetts area, they were not consumed by
older fish. A significantly greater food diversity has been noted in
younger specimens of northern searobin *180*.
Food Habits - 1 (DRAFT) - Environment Associations
Species searobin, northern
Species Id M010501
Date 26 AUG 96
ENVIRONMENTAL ASSOCIATIONS
G = General A = Adult
LIM = Limiting RA = Resting Adult
J = Juvenile FA = Feeding Adult
RJ = Resting Juvenile BA = Breeding Adult
FJ = Feeding Juvenile P = Pupae
L = Larvae E = Egg
RL = Resting Larvae
FL = Feeding Larvae
LIFESTAGE ENVIRONMENTAL ASSOCIATIONS
G Water Temperature: Specified in Comments
G
G Bottom Type [Aquatic]: Sand
G Relation to Substrate: Unattached - normally free living
A Water Depth Preference: Specified in Comments
J Water Depth Preference: Specified in Comments
A Estuarine habitat zone: bay
A Estuarine habitat zone: sound
A Estuarine habitat zone: offshore
J Estuarine habitat zone: offshore
REFERENCES FOR ENVIRONMENTAL ASSOC_ - 180
REFERENCES FOR RESTING ADULT ENVIRONMENTAL ASSOC_ - 180
REFERENCES FOR RESTING JUVENILE ENVIRONMENTAL ASSOC_ - 180
COMMENTS ON ENVIRONMENTAL ASSOCIATIONS -
TEMPERATURE: Searobin species entered New England waters at water
temperatures slightly above 4.4 deg C and left at temperatures a little
below 15.5 deg C. The northern searobin in the Delaware river left at
higher temperatures: of the 794 caught, only 10 were taken after September
when the temperaure fell below 18 deg C. Northern searobin can tolerate a
temperature difference of 13 deg C. Temperatures range from 9 deg C
inshore in the summer to 6 deg C offshore in the winter.
SALINITY: No northern searobin were taken below 20 o/oo and only a few
below 27 o/oo in the Delaware River.
SUBSTRATE: Northern searobin prefer a sandy substrate.
HABITAT ZONES: The species is found from the estuaries to the edge of the
continental shelf *180*.
COMMENTS ON RESTING ADULT ENVIRONMENTAL ASSOC_ -
WATER DEPTH: Adult and juvenile northern searobin north of Cape Hatteras
migrate from mid-shelf (15-60 fm) and far-shelf (60-200 fm) waters inshore
(0-15 fm) into the Long Island, New York area.
HABITAT ZONE: The species can be found from the estuaries to the edge of
the continental shelf *180*.
Environment Associations - 1 (DRAFT) - Environment Associations
Species searobin, northern
Species Id M010501
Date 26 AUG 96
COMMENTS ON RESTING JUVENILE ENVIRONMENTAL ASSOC_ -
WATER DEPTH: Adult and juvenile northern searobin north of Cape Hatteras
migrate from mid-shelf (15-60 fm) and far-shelf (60-200 fm) waters inshore
(0-15 fm) into the Long Island, New York area.
HABITAT ZONE: Juveniles are regularly mixed with adults in ocean surveys.
Few are reported in estuarine surveys *180*.
Environment Associations - 2 (DRAFT) - Life History
Species searobin, northern
Species Id M010501
Date 26 AUG 96
LIFE HISTORY
MORPHOLOGY: External adult morphology: Searobins typically have broad,
moderately spiny heads, slender bodies triangular in cross section, large
fan-like pectorals with the lower three rays separate and modified for
feeling or "walking" on the bottom, two separate dorsal fins (one spiny and
one soft-rayed), and ventral fins located under the pectoral fins.
Dorsal rays usually 13, sometimes 14. Anal rays usually 12, infrequently 11
or 13 (in about 2% of specimens each).
Attached pectoral rays usually 14, sometimes 13 (in about 8%), or 15. Gill
rakers usually 1 on upper limb, sometimes 2 rarely none, lower limb usually
with 11 or 12, often 13, rarely 10; combined number on both limbs 11-15;
tubercles 1-3 on upper limb and 3-6 on lower. Maxillary ending on a
vertical nearer posterior nostril than eye, a little in advance of normal
position of buccal spinule. Spines on head moderately delevoped: buccal,
rostral, and supplemental preopercular spines disappearing at about 70, 150,
and 170 mm, respectively, but individual variability of size at
disappearance very pronounced; lachrymal plate moderately projecting, its
serrature moderately developed. Occipital groove fairly marked in the
smaller specimens, its middle and greater portion disappearing with growth,
generally only a small terminal part present in large specimens, sometimes a
trace of middle part appreciable also in large specimens. Chest fully
scaled. (The chest fully scaled on 2 specimens 28 mm, nearly as in adult;
in 2 specimens 28 mm, and 4 specimens 27 mm, the chest is all scaled or
nearly so but not as fully imbricated as in adult; in one each 26 and 23
mm, the chest naked.) First 3 dorsal spines graduated, the third longest,
fourth spine slightly shorter or subequal to third. Anterior 3 dorsal
spines and first ray moderately serrate; the first ray unbranched. Second
ray branched except in infrequent variants. Pectoral not having its distal
edge emarginate; fourth ray (from top) longest, the rays decreasing in
length both ways, the lower posterior margin making a broad curve; the fin
reaching to over base of fifth to eighth anal ray. Caudal well emarginate.
Measurements of 6 specimens 131-198 mm: depth 18-20, head 33-35, maxillary
10.5-13, interorbital 4-5; eye 6-7. Pectoral measurements segregated by
geographic regions.
Color pattern variable and changing with growth; young specimens typically
with a cross banded pattern; upper part of body having alternate areas of
dark and light shades, usually better marked when viewed from dorsal aspect;
one dark area under spinal dorsal, two under soft dorsal, one each near its
beginning and near its end, a narrow one at caudal base; this pattern often
well or fairly marked in the small specimens, varying from faint to being
sharply outlined, often irregularly spotted or blotched; the juvenile
pattern tending to disappear with growth, usually absent in large specimens
or only a trace left in occasional examples; after disappearance of cross
banded pattern, some variants having a row of whitish spots or areas at
dorsal profile, usually one between the two fins, two at soft dorsal base,
one at caudal base, occasionally white spots up to six in number, the white
spots especially marked in dark variants; in addition to cross banded
pattern, anterior part of body usually with many small crowded diffuse
spots, only moderately darker than ground color, often the small spots few
or absent; the larger specimen often with very small whitish or pearly
spots following rows of scales. Pectoral almost uniformly dark to black;
often a variable area along upper margin and sometimes also along lower
Life History - 1 (DRAFT) - Life History
Species searobin, northern
Species Id M010501
Date 26 AUG 96
margin whitish; sometimes one or two broad, irregular, oblique cross areas
of a slightly lighter tinge; upper region sometimes with faintly outlined
small spots of a slightly darker shade than ground color. Spinal dorsal
spot confined between fourth and fifth spines, usually placed more or less
below edge of fin, usually partly or wholy surrounded by a narrow hyaline or
whitish area; this fin usually with lengthwise or oblique, continuous or
broken hyaline bands.
Fresh coloration is a grayish or reddish brown upper body with five dark
saddlelike blotches along the back. Ventrally the body is dirty white or
pale yellow. Dorsal fins are grayish with pale spots and stripes and with a
black spot between the fourth and fifth spines. Caudal fin gray to brown;
anal fin brown; ventrals yellow to brown. Pectorals yellow to orange
marked with two broad dusky bars; one medially and the other on the outer
third. Pectoral filaments orange.
Eggs: The eggs are spherical in form at 1 to 1.5 mm in diameter. They are
slightly yellowish in color but highly transparent. The yolk sphere
contains a variable number (10 to 25) of oil globules of unequal size
scattered over the surface. As development advances, some of these globules
may become aggregated. Usually, however, they remain distributed more or
less uniformly over the surface of the yolk. The egg membrane is thin and
horny.
Embryo: Within 20 hr after fertilization the embryo is well differentiated
and extends halfway around the circumference of the yolk sphere. The
blastopore is not yet closed. The embryo shows 10 to 12 somites and
pigmentation has already begun. Numerous yellow and black pigment cells are
present over the entire surface of the embryo and in the adjacent areas of
the extra-embryonic blastoderm. Pigment cells arises earliest in the embryo
and gradually become apparent in the remoter parts of the blastoderm.
Yellow pigment arises somewhat earlier than black pigment in these embryos.
At 42 hr after fertilization both black and yellow chromatophores are larger
and fewer in number than during the earlier stages. They are now sparsely
distributed over the surface of the embryo and throughout the
extra-embryonic blastoderm.
Larvae: Newly hatched larvae are approximately 2.8 mm in length. The yolk
sac is relatively small and still contains oil globules. The head is not
markedly deflected. The vent is located just posterior to the yolk sac.
The pectoral fins are prominent (the depth of either dorsal or ventral fin
fold is greater than the depth of the body posterior to the vent). Black
and yellow chromatophores are sparsely scattered over the head, the anterior
region of the trunk, and the dorsolateral and ventrolateral aspects of the
trunk farther posteriorly. The body is marked further by two transverse
yellow bands, one just posterior to the pectoral fins, the other
approximately halfway from the vent to the posterior end of the body. These
bands of pigment extend onto the fin folds. The general color of the head
and pectoral fins is yellowish. As development advances a material
reduction of the yellow pigment becomes apparent. Five days after hatching
the yellow markings characteristic of the newly hatched larvae are no longer
apparent. The head and the pectoral fins still show yellow pigment. Some
yellow chromatophores also remain at the vent and at the former location of
the posterior transverse band. Black chromatophores are sparsely scattered
Life History - 2 (DRAFT) - Life History
Species searobin, northern
Species Id M010501
Date 26 AUG 96
over the body and a few appear also in the dorsal and ventral fin folds.
The posterior caudal region remains practically free from pigment.
Larval fish five days old have grown to a length of 3.1 to 3.4 mm. The head
is relatively large. The pectoral fins are large and prominent. Young fish
4 mm in length are characterized by a very large head and relatively great
depth of the body in the anterior region of the trunk. The ground color of
the body remains yellowish. Black chromatophores occur sparsely scattered
over the dorsal and lateral aspects of the body and in a series along the
ventrolateral aspect of the body near the base of the ventral-fin fold.
In young fish 8 to 10 mm in length the dorsal, anal, and caudal fins are
becoming well differentiated, and the free rays of the pectoral fins
characteristic of the species are already present. The general color of the
body and the distribution of black chromatphores remain essentially as in
the preceding stage.
Juveniles: In young fish 25 to 30 mm in length the general color of the
body has become darker, and the trunk is marked by heavily pigmented areas
that give it a transversely banded appearance. The fins are well
differentiated. The head is long and somewhat pointed and shows bony the
structure characteristic of the adult. The young fish are gradually
assuming the appearance of the adults and already show many of the
diagnostic characters of the species.
REPRODUCTION: Sexuality: The species is heterosexual. Hermaphroditism is
not reported.
Maturity: Northern searobin reach sexual maturity at an age of 2-3 years
and about 200 mm, corresponding to about 85 g, in the Chesapeake Bight.
One-year-olds (14 cm) from New England waters were capable of producing ripe
eggs, however the ovaries were small and the number of eggs few.
Mating: There is indirect evidence that searobins produce a staccato call
thought to characterize the breeding season as opposed to a grunting sound
they usually emit.
Fertilization: Fertilization is external.
Gonads: Developing testis are opaque white and elongate (approximately
40x10 mm in an adult). Eggs are not visible to the eye. Ovaries are yellow
to orange.
Ripe testis are opaque white. Ripe ovaries are yellow to orange, eggs are
now visible, granular in texture, have faint to prominent blood vessels, and
are triangular in shape. Adult specimen 240 and 265 mm in length and
ovaries weighing 10.66 to 9.27 g respectively.
Conspicious "variability" of egg size and development throughout is
reported. The largest eggs, whether ripe or partially so, are not grouped
but are scattered amongst less developed eggs of diverse sizes. Correlated
with this is the fact that few eggs are ripe at any one time and the
breeding season is somewhat prolonged. The diameter of the largest eggs
taken from several ripe ovaries averaged 0.2 mm to 1.0 mm.
Spawning: In a study of northern searobin from the continental shelf of
the Chesapeake Bight gonads of sexually mature fish began to increase in
size in March. By May, some fish were gravid, and in July the running ripe
condition was observed. Running ripe fish were prevalent in August and
Life History - 3 (DRAFT) - Life History
Species searobin, northern
Species Id M010501
Date 26 AUG 96
early September. Most fish were spent by November, except for a few males.
The gonads of fish caught in February appear little different from those
found in November. The incomplete data indicated that the spawning season
in 1966 in the Chesapeake Bight was July, August, and at least part of
September. Spawning reportedly occurred earlier at Woods Hole in June,
July, and early August.
Embryos: Eggs develop in a manner typical of pelagic teleostean eggs. They
are somewhat larger than the eggs of Tautoga onitis, and therefore
development advances somewhat less rapidly. The volume of protoplasm in
proportion to the volume of yolk is relatively small, yet the blastodisc is
relatively thick; consequently, during the early stages of cleavage the
blastodern covers a relatively small area of the surface of the yolk sphere.
The first act of cleavage occurs within 1.5 hr of fertilization. The
successive acts of cleavage follow each other very regularly. The early
blastoderms are usually more nearly symmetrical than are those of Tautoga
onitis or either of the other species described.
LONGEVITY: It was determined from a study of otoliths that the oldest fish
in Chesapeake Bight samples was 11 years (298 mm, 326 g).
HARDINESS: Northern searobin can tolerate a temperature difference of 13
deg C. Temperatures range from 19 deg C inshore in the summer to 6 deg C
offshore in the winter.
PREDATORS: Dusky shark, sand bar shark, man.
COMPETITORS: No information available.
PARASITES: Nematodes (Ascarids - immature; encapsuled in peritoneum)
Cestodes (Rhynchobothrium - encysted on viscera, and Tetrarhynchus
bisulcatus Linton - encysted in stomach and intestine)
Trematodes (Distomum appendiculatum Rudolphi - intestine, Distomum sp. -
intestine, and Diplostomum sp. - intestine)
NUTRITION AND GROWTH: Feeding: The digging and "feeling" movement
exhibited by the modified pectorals of searobins has been connected with the
search for food. In 1884, searobins were observed using their modified
pectorals to stir up the weeds and sand to rout out the small animals on
which they fed. This observation was supported by findings that blinded
anosmic searobins responded by digging when food extracts were placed in the
water proximal to their modified pectorals.
Although research indicates that the modified pectorals are involved with
the detection of food, other findings indicate that searobins most likely
feed on organisms on or just above the bottom rather than burrowed in the
bottom. This conclusion was reached when the stomach contents of searobins
were compared with the most abundant organisms listed in bottom samples of
the same area and little correlation was found.
Food: A typical description of northern searobin stomach content from the
Woods Hole region was made in 1901: Stomachs and intestines of this species
have yielded a variety of material. In one specimen were found a young
herring, several small clams (Mya), two shrimp (Palaemonetes), and a pebble.
Life History - 4 (DRAFT) - Life History
Species searobin, northern
Species Id M010501
Date 26 AUG 96
Small specimens have yielded shrimp in large numbers, amphipods and other
small crustaceans, squid and lamellibranch mollusks, annelids, and seaweed.
One small specimen had four young winter flounder in its stomach.
The following general listing was given in 1963: shrimp, crabs, amphipods,
squids, bivalve mollusks, annelid worms, small fish (i.e. herring, menhaden,
winter flounder), seaweed, any bait.
Growth rate: Northern searobin in New England waters reach a maximum of
381-406 mm with fish less than 305 mm common.
A statistically significant difference was found in the weight of male and
female northern searobin of the same length from the New York Bight. While
length-weight slopes for the two sexes did not differ significantly
(P>0.05), the intercepts did (P<0.01). Calculated weights of females 200 mm
long were found to be 4% heavier than males of the same length.
Length-weight equations and sample size (n) for northern searobin from trawl
surveys in the New York Bight from June 1974 to June 1975 were:
log10 W = -4.9951 + 2.9935 (log10 L), n = 257 males
log10 W = -5.0242 + 3.0135 (log10 L), n = 248 females
W = weight (g)
L = fork length (mm)
MIGRATION: A seasonal migration occurs north of Cape Hatteras; inshore
during spring months and offshore in late fall. Not enough data is
available to determine if there is inshore-offshore migration south of Cape
Hatteras or the extent of a north-south migration, if any.
SCHOOLING: There is no evidence of schooling although occasional large
catches of fish are reported in the results of the National Marine Fisheries
Service spring and fall groundfish surveys offshore near the 100 fathom
line. These catches range from 300 to several thousand fish with one catch
of 39,280 reported off Maryland in the 1973 spring groundfish survey. In
general, searobins are taken regularly, with the numbers varying with the
time of year and the distance from shore.
RESPONSE TO STIMULI: Auditory: It may be possible to elicit a staccato
call from searobins, thought to characterize the breeding season, by playing
imitations and recordings of the call into the water. In a controlled study
of response to sound made by an iron ball hitting the side of a wooden tank
it was found that P. carolinus exhibited unmistakable tendencies to gather
near the sound center.
Optical: It was reported that as a result of visual disturbances, the
searobin exhibited ventilatory pauses, and changes both in rate and
amplitude and an associated transitory bradycardia (of the heart).
Chemical: Researchers found that blinded anosmic searobins showed a strong
digging response when extracts of rotted clams, worms, or squid were applied
to the water near their modified pectoral fins. The response to fresh
extracts was weaker. The fish had a positive response to milk. The digging
response was elicited also by application of several amino acids. When the
lips or mouth were stimulated, the animals responded by swallowing or
gulping instead of digging.
Life History - 5 (DRAFT) - Life History
Species searobin, northern
Species Id M010501
Date 26 AUG 96
POPULATION: Sex ratio: The sex ratio of searobins was found to be
approximately 1:1 in the Chesapeake Bight and the New York Bight.
Size and age composition: From interpretation of a length-frequency graph,
180-300 mm in length fish is present in the Chesapeake Bight year-round.
This size class includes fish from I-VIII years in age. A second
length-frequency group, less than 180 mm, was also present year-round.
These fish are age groups 0 or I and the progression of their modal length
depends on the season.
ABUNDANCE AND DENSITY: Relative abundance: Northern and striped searobin
were reported to be in the ratio of 2.5:1 from June to September in Buzzards
Bay and Vineyard South, Massachusetts. A similar ratio was obtained in the
New York Bight.
Results of National Marine Fisheries Service sport fishing surveys in the
northeastern United States from June 1973 to June 1974 rank searobins tenth
in weight of "other finfish" falling behind bluefish, striped bass,
weakfish, tautog, scup, dogfish, other (miscellaneous species), spot, and
black seabass in descending order. They ranked higher than croakers,
cunner, cusk, black drum, red drum, kingfishes, Spanish mackerel, puffers,
shad, skates, smelt, tilefish, and toadfish.
Of the 21 groups of "other finfish" mentioned above, ICNAF commercial
landings record searobins varying usually from 9th to 18th in weight over a
12 year period with a single high rank of third in 1968. They were usually
greater than the angler, tilefish, wolffishes, bluefish, croaker, black
seabass, spot ,and squeateague.
Actual abundance: No information available *180*.
LIFE HISTORY CODES -
Foraging Sites: Standing water - Limnetic zone
Foraging Sites: Standing water: Profundal zone
Breeding/Spawning Season: June
Breeding/Spawning Season: July
Breeding/Spawning Season: August
Breeding/Spawning Season: September
Spawning Site: Sand
Parental Care of Young: No care given young
REFERENCES FOR LIFE HISTORY- 180
Life History - 6 (DRAFT) - Management Practices
Species searobin, northern
Species Id M010501
Date 26 AUG 96
MANAGEMENT PRACTICES
RESULT MANAGEMENT PRACTICE
Existing Regulating commercial harvest levels
REFERENCES FOR EXISTING MANAGEMENT PRACTICES - 180
COMMENTS ON MANAGEMENT PRACTICES -
At present searobins fall within the category "other finfish." A total
allowable catch (TAC) is set by ICNAF for these fish collectively. The TAC
recommended by the NMFS for 1977 was 150,000 tons. On attainment of the
quota all fisheries are terminated and subsequently only incidental catches
(1% of the total weight of all other fish on board) are allowed *180*.
Management Practices - 1 (DRAFT) - References
Species searobin, northern
Species Id M010501
Date 26 AUG 96
References
180* Roberts, S.C. 1978. Biological and fisheries data on northern searobin,
Prionotus carolinus (Linnaeous). National Marine Fisheries Service, NOAA,
TR No. 13, Highlands, New Jersey, 53 pp.
References - 1