(DRAFT) - Taxonomy
Species pigfish
Species Id M010022
Date 26 AUG 96
TAXONOMY
NAME - pigfish
OTHER COMMON NAMES -
ELEMENT CODE -
CATEGORY - Fish
PHYLUM AND SUBPHYLUM - Chordata,
CLASS AND SUBCLASS - Osteichthyes,
ORDER AND SUBORDER - Perciformes,
FAMILY AND SUBFAMILY - Haemulidae,
GENUS AND SUBGENUS - Orthopristis,
SPECIES AND SSP - chrysoptera,
SCIENTIFIC NAME - Orthopristis chrysoptera
AUTHORITY - Linnaeus
TAXONOMY REFERENCES - 76
Taxonomy - 1 (DRAFT) - Status
Species pigfish
Species Id M010022
Date 26 AUG 96
STATUS
Coded Status
Unclassified
REFERENCES FOR STATUS - 76
COMMENTS ON STATUS -
Pigfish are common inhabitants of warm gulf waters. They are frequently
taken by sport anglers, especially in Florida waters, and are considered to
be a good quality food fish; however, they have only limited economic
importance. Pigfish are often trapped and used for live bait. They are
also used as a source of food by other predatory species.*76*
Status - 1 (DRAFT) - Distribution
Species pigfish
Species Id M010022
Date 26 AUG 96
DISTRIBUTION
Distribution - 1 HABITAT ASSOCIATIONS
Habitat Associations - 1 (DRAFT) - Food Habits
Species pigfish
Species Id M010022
Date 26 AUG 96
FOOD HABITS
TROPHIC LEVEL -
CARNIVORE
REFERENCES FOR TROPHIC LEVEL - 76
LIFESTAGE FOOD FOOD PART
Juvenile Crustaceans Not Specified
Juvenile Copepods Not Specified
Juvenile Polychaetes Not Specified
Adult Crustaceans Not Specified
REFERENCES FOR ADULT FOOD - 76
REFERENCES FOR JUVENILE FOOD - 76
COMMENTS ON FOOD -
Feeding habits of pigfish vary with growth stage; they are primarily
benthic carnivores as adults, possibly feeding nocturnally, while young fish
are planktivorous. A shift in diet has been found relative to increasing
length for pigfish taken from Crystal River, Florida. Small fish eat mostly
copepods, while larger fish shift to a diet of amphipods, shrimps, and
other benthic organisms. Two distinct feeding phases have been found.
Smaller pigfish (16-30mm) are planktivorous (eating copepods, mysids, and
postlarval shrimp), followed by a two-phase carnivorous stage in which
benthic invertebrates were the major food items. The transition from
planktivore to carnivore is gradual beginning at about 26 mm SL, and is
complete by 41-45mm SL. Polychaetes are important in the diet of pigfish
longer than 30 mm, but as fish grow larger than 55 mm, caridean and penaeid
shrimp are consumed more frequently.*76*
Food Habits - 1 (DRAFT) - Environment Associations
Species pigfish
Species Id M010022
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
LIM Water Temperature: Specified in Comments
LIM
G Dissolved Oxygen: Specified in Comments
J Bottom Type [Aquatic]: Rooted aquatic vegetation
A Bottom Type [Aquatic]: Mud or silt
A Bottom Type [Aquatic]: Sand
A Bottom Type [Aquatic]: Rooted aquatic vegetation
REFERENCES FOR ENVIRONMENTAL ASSOC_ - 76
REFERENCES FOR LIMITING ENVIRONMENTAL ASSOC_ - 76
REFERENCES FOR FEEDING ADULT ENVIRONMENTAL ASSOC_ - 76
REFERENCES FOR FEEDING JUVENILE ENVIRONMENTAL ASSOC_ - 76
COMMENTS ON ENVIRONMENTAL ASSOCIATIONS -
Temperature and Salinity:
Temperature and salinity values of 25.2 degrees C and 25 ppt were found in
Crystal River, Florida, when pigfish were most abundant. During December
to April, when pigfish were taken less frequently, values of 15.9 degrees C
and 26.5 ppt were recorded. In another study, pigfish were collected from
Florida waters at temperatures of 19.5 to 30.6 degrees C. and salinities
of 17.2 to 44.1 ppt. A temperature range of 13.7 to 36 degrees C and a
salinity range of 0 to 38 ppt was provided on the basis of published
values for pigfish throughout the gulf. A tolerance range of 19.1
to 35 ppt (mean - 28.9ppt) and 17.5 to 32.5 degrees C was reported for
pigfish collected in Tampa Bay, Florida. In Barataria Bay, Louisiana,
pigfish were taken between 6.2 and 24.3 ppt and between 17.3 and 30.0
degrees C. Pigfish apparently avoid low-temperature water migrating to
deeper water during the winter. Pigfish were absent in collections made at
water temperatures of 12 to 14 degrees C; however adults were abundant
when waters of St. Andrew Bay, Florida, warmed to 16.5 to 31.0 degrees C.
Pigfish were not collected when water temperatures in Pinellas County,
Florida dropped below 12.5 degres C. They were killed during a cold
wave that caused water temperatures to drop to 4.5 degrees C.
Salinity:
Low salinity areas also appear to be avoided by pigfish. In Charlotte
Environment Associations - 1 (DRAFT) - Environment Associations
Species pigfish
Species Id M010022
Date 26 AUG 96
Harbor, Florida, pigfish were not taken in waters with salinity values less
than 15 ppt. In one study, all pigfish less than 50 mm TL and greater than
200 mm TL in Texas gulfwaters were found in salinities greater than 25 ppt;
no specimens were taken in less than 10 ppt. A mass mortality of pigfish
was noted (as well as other species) after a hurricane caused salinities to
drop from 23.5 ppt to 9.7 ppt over a 4-day period in Goose Cove Florida.
However, it was probably the rapid drop rather than the low salinity that
caused the mortality.
Dissolved Oxygen:
Pigfish were collected from waters with dissolved oxygen concentrations of
2.1 to 11.8 ppm in Cape Fear Estuary, North Carolina.
Substrate:
Juvenile pigfish in Crystal River were found on shallow flats with
considerable plant growth during spring and early summer. As the summer
and fall progressed, juvenile pigfish moved to deep flats and the edges of
channels. Adults were taken from deeper flats and channels with sparse
vegetation. Adult pigfish occurred most frequently over mud bottoms and
occasionally over sandy, vegetated areas, hard substrates such as reefs and
jetties and offshore platforms.*76*
Environment Associations - 2 (DRAFT) - Life History
Species pigfish
Species Id M010022
Date 26 AUG 96
LIFE HISTORY
Morphology and Identification Aids:
Body ovate-elliptical, considerably compressed, its depth contained 2.6 to
3.0 times in standard length (SL). Posterior edge of upper jaw not reaching
to below eye; two pores and a median groove on chin; jaws with a narrow
band of slender teeth; preopercular margin very slightly serrate; gill
rakers short and slender, about 12 on lower limb of first arch. Dorsal fin
with 12 or 13 spines and 15 or 16 soft rays; anal fin with 3 spines and 12
or 13 soft rays; dorsal and anal fin spines enclosed in a deep scaly
sheath, the soft rays naked. Scales ctenoid; pored lateral-line scales 55
to 58; 10 longitudinal rows of scales above the lateral line and 19 rows
below.*76*
Color of body: light blue-gray above, shading gradually into silver below;
each scale of body with a blue center, the edge with a bronze spot; these
spots form distinct orange-brown stripes extending obliquely upward and
backward on back and sides, those below being nearly horizontal; head with
bronze spots; fins yellow-bronze with dusky margins.*76*
Spawning:
Pigfish mature by their second year of life. It was concluded that spawning
in gulf waters near Cedar Key, Florida, was probably in spring, since small
young-of-the-year first appeared in May. A bimodal frequency curve for that
month was also noted, suggesting that pigfish in this area of the gulf may
have two breeding peaks or "growth spurts". Adult females taken during July
from the Cedar Key area showed some signs of maturing gonads; however, they
were far from ripe. After comparing average monthly lengths and seasonality
of fish in other areas, it was concluded that pigfish apparently spawn in
about March in gulf waters near Crystal River, Florida. Ripe males were
found in Texas gulf waters in March and April and it was suggested that the
fish probably spawn there before June.
Other studies from the Gulf of Mexico also indicate that spawning occurs in
the late winter or spring: Tampa Bay, Florida, March-May; eastern Gulf of
Mexico, January-May ; and Horn Island, Mississippi, March-April. Pigfish
larvae were found off Port Aransas from late February through June.
Spawning may occur in open water prior to inshore migrations during
March-April in St. Andrew Bay, Florida.
Pigfish spawn during March to June along the inside shores of Bogue and
Shackleford Banks, North Carolina, and within the harbor and estuaries on
the outer shores of these banks. Spawning apparently takes place during the
early evening hours.*76*
Eggs: Pigfish eggs are buoyant, highly transparent, and spherical (0.7 to
0.8 mm in diameter). The eggs have a single oil globule (rarely two or
three) that averages 0.16 mm in diameter. Pigfish eggs are easily confused
with those of silver perch (Bairdiella chrysoura). This problem is
magnified by the fact that the two species spawn at nearly the same time and
in similar areas.*76*
Larvae:
Pigfish larvae can be separated from those of other haemulids (grunts) by
the presence of 11 soft rays in the anal fin. In the eastern gulf, one peak of
of abundance of pigfish larvae was found in late winter and spring, mainly
Life History - 1 (DRAFT) - Life History
Species pigfish
Species Id M010022
Date 26 AUG 96
inside a depth of 50 m.*76*
Juveniles:
Juvenile pigfish are fully scaled by 25 mm SL and achieve adult form by 70
mm SL. At 25 mm, they have a prominent dark midlateral band with
an additional dark band from the nape to the base of the
second dorsal fin. The mid-lateral bands often disappear at a length
of approximately 40 mm SL, but the anterior position of the lower band may
remain longer. Juvenile pigfish have yellow and green horizontal lines
along their sides that are most prominent on the cheeks and opercles.
Researchers working in an area of thermal effluent near Crystal River,
Florida, first noted young-of-the-year pigfish in trawl samples taken during
June. Juvenile pigfish (smallest, 12.5 mm SL) were first taken in April
from Tampa and St. Andrew Bay, Florida. Juveniles were most abundant during
May in Cedar Key, Florida. In Alligator Harbor, Florida, juveniles were
reported present by June. Smallest pigfish were collected in shallow bays
along the Texas gulf coast.
Juvenile pigfish may associate with other species of fish. In Charlotte
Harbor, Florida, young pigfish (16-25 mm SL) were found in mixed schools
with small pinfish.*76*
Adults:
Adult pigfish are common in the northern and more saline coastal areas of
the Gulf of Mexico. Adult pigfish have been found in Cedar Key Florida
throughout the year, but are most abundant during summer months. Along the
coastal areas of north Florida, pigfish have been reported to be among the
most abundant finfish collected.
Adult pigfish also occur in the offshore and open-shelf areas of the Gulf of
Mexico. Pigfish may be more abundant in offshore waters than inshore in the
southern regions of the Gulf of Mexico. Pigfish are also abundant on the
shell banks off Campeche, Mexico.*76*
Growth Characteristics:
Pigfish reach a maximun length of 46 cm SL and a weight of 0.9 kg (2 lb).
Few pigfish older than 3 years old and very few age 4 fish have been taken
along the Atlantic coast. Based on information available on growth of
pigfish in gulf waters, growth rates range from 7 mm SL/mo to 9.3 mm SL/mo
from June to October. Growth during October to April slows to 3.1 mm SL/mo
to 5.5 mm SL/mo.*76*
Predators:
Pigfish are prey of Atlantic sharpnose sharks, spotted seatrout, and
weakfish. Other large piscivores, such as snapper and grouper, probably
also prey on pigfish.*76*
Parasites and Diseases:
Pigfish have been reported to be parasitized by a monogenetic trematode that
infests the gill filaments. Pigfish were killed by red tides in Tampa Bay,
Florida.*76*
REFERENCES FOR LIFE HISTORY- 76
Life History - 2 (DRAFT) - Management Practices
Species pigfish
Species Id M010022
Date 26 AUG 96
MANAGEMENT PRACTICES
COMMENTS ON MANAGEMENT PRACTICES -
Pigfish are taken in seines, traps, trawls, and by handlines. *76*
Management Practices - 1 (DRAFT) - References
Species pigfish
Species Id M010022
Date 26 AUG 96
References
76* Sutter, F. C., T. D. McIlwain. 1987. Species Profiles: Life
Histories and Environmental Requirements of Coastal Fishes and
Invertebrates (Gulf of Mexico) -- Pigfish. U.S. Fish and
Wildlife Service Biol. Rep. 82(11.71) pp 11.
References - 1