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Catfishes - Family Ictaluridae, habitats, characteristics, fishing methods.
Catfishes - family Ictaluridae is also known as the North American freshwater catfishes range from very
small to very large fish. There are 38 species of this family known from the United States. The catfishes
are scaleless fishes with a spinous ray in the front of the dorsal fin and each pectoral fin. The
catfishes are restricted to fresh waters in North America from southern Canada to Guatemala. There are
about 65 species. Local catfishes are divided into four groups, the flathead catfish, madtoms, bullheads,
and the channel catfish. The madtoms can inflict a painful wound with the pectoral spines and their
associated venom glands, but they are not as likely to be seen as often as the other catfishes because of
their miniature size, their secretive nature, and their rarity or scattered distribution. The channel
catfish and most madtoms inhabit rather rapidly flowing waters; bullheads and flathead catfishes are
usually in slowly moving waters. All catfish are spring spawners. One or both bullhead parents guard their
eggs and young. The flathead catfish attains a weight in excess of 50 lbs in our waters and the channel
catfish may exceed 40 lbs. Catfishes are omnivorous and feed largely on invertebrates, including aquatic
insects and their larvae. Catfishes tend to be nocturnal and benthic.
Catfishes are popular sport fish. Some species are raised commercially for human consumption, and the tiny
ones are part of the forage base of small fishes in their home lakes or streams. Some madtoms are
considered indicators of water quality. In all ictalurids, the five anterior vertebrae are modified and
are known as Weberian ossicles. These function in transmitting vibrations (sound) to auditory receptors in
the brain.
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They do not have scales, with a tough, smooth skin, and possess 2 to 4 pairs of long sensory
whiskers or barbels around their mouth - 4 on the chin, and 4 on the upper jaw (2 on the snout, and
1 on each corner of the mouth). They have 3 median fins: anal, adipose, and dorsal. The anal fin has
a long base and is located on the underside of the fish. The dorsal fin is located on the back and
has a single sharp spine near the gills in the front part at the leading edge of the dorsal fin. In
some species these spines may contain poison. The adipose fin is a small, fatty fin situated between
the dorsal fin and the tail. There are 2 sets of paired fins, the pelvic and pectoral fins. Both
pectoral fins have a single spine along the front section of the fin, which inflict the notorious
sting of the catfish.
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All species are equipped with spines which may inflict wounds of varying discomfort from a
short period of numbness and moderate swelling to extreme discomfort and swelling that may last for
several days, especially the madtoms have poison glands associated with these spines that are which can
inflict a painful, but not dangerous, wound. The armament of the pectoral spines (serrae) and the anal and
caudal fin ray counts are important taxonomic characters in the ictalurids. On madtoms, the adipose fin, a
fleshy lobe between the dorsal fin and the tail fin, is joined with the tail fin. On other catfish, the
adipose fin is separate. Some catfish have moderately to deeply forked tails. Albinism, which results in a
white-colored, pink-eyed catfish, is known to occur.
Catfish spawn in spring to early summer. All species of catfish build nests. Both males and
females may contribute to nest site selection and construction and guarding of nests and young. catfish
and bullheads frequently select holes under overhanging banks in rivers and reservoirs as nesting sites,
although bullheads also nest in open areas. Madtoms typically spawn under slab rocks, but many spawn in
enclosed areas such as cans or other containers. The female is clasped by the male and is stimulated to
deposit a mass of sticky eggs. The male or both parents guard the nest and protect the young for a time.
Young catfish form tight schools and separate individually only to hide when they have been frightened.
Adult catfishes are most active at night. When they are active in daytime, it is generally in muddy,
clouded water. They have poor vision and use the sense of smell and the taste buds on the skin, lips and
barbels to find food.
Nuptial males of all catfish develop swollen lips and dorsal head musculature, and typically do not feed
during nesting.
Flathead catfish are one of the biggest fish, may grow to more than 100 pounds. Flathead
catfish have the scaleless, strong, long and slender body and the well-developed pectoral and dorsal fin
spines typical of catfish. They have very wide and depressed flat-looking head. The square or rounded tail
is slightly indented. The dorsal fin is high, and the lower jaw projects past the upper jaw. The color is
yellowish brown to dark, even purplish brown, with black or brown mottling on lighter brown sides. The
belly is grayish or yellowish white. The chin barbels are white to yellow, the fins are mottled, and the
anal fin, which has fewer than 16 rays, is short and rounded. Except for very large adults, flathead
catfish have a white tip on the upper lobe of the caudal fin. Young flathead catfish and young adults are
often nearly black dorsally and have a white blotch on the tip of the dorsal lobe of the caudal fin. The
posterior end of the adipose fin is not attached to the dorsal surface of the body. The pectoral fin spine
has well developed posterior and anterior serrae. They can live to at least 19 years old. This catfish is
an excellent sport and food fish, and may locally be called mudcat or yellow cat.
Flathead catfish are found in medium to large rivers and reservoirs, streams and lakes,
usually over hard bottoms. They prefer deep, sluggish pools, with logs and other submerged debris that can
be used as cover. It typically spends daylight hours associated with cover such as caves, undercut banks,
brush piles, or log jams. Juveniles are commonly found in riffle areas where they feed mostly on immature
aquatic insects. Adults forage at night in a wide variety of habitats, including riffles so shallow that
the dorsal fin may be exposed Young flatheads live in rocky or sandy runs in the river and in the riffles.
Flatheads grow fairly rapidly and mature sexually at about 15 inches and 5 years old. The
flathead is a loner and a traveler, leading a solitary existence except at spawning time. Flatheads spawn
in early summer, later than channel catfish. The flathead�s spawning behavior is like that of other
catfish. The adults form pairs and build nests in natural cavelike depressions in the bank, or they may
hollow out a cavity under an underwater object, like a log or boulder, or similar object. Their compact
egg masses contain from 4,000 to 100,000 eggs. The male guards the nest after spawning and the newly
hatched fry, becoming aggressive toward the female.
Next to the flathead catfish, the channel catfish is the largest catfish. Weights of up to
15 pounds are not unusual at lengths of about 30 inches. The channel cat has a deeply forked tail, with
tail lobes that are sharply pointed. In bigger fish, the fork is less noticeable or disappears. Channel
cats have 24 to 30 rays on the anal fin, a small, fleshy adipose fin that is separated from the tail, and
typical catfish spines on its dorsal and pectoral fins. The barbels are black and long. The channel
catfish is pale gray to olive dorsally and white to yellowish belly. The sides of the young and often of
adults silvery-gray and have scattered dark spots. The median fins have dusky to black borders. Except for
some large adults, especially the males, channel catfish have small, irregular spots on the sides and
back. None of the other catfishes has these spots. Males become darker, almost blue-black, during spawning
time. The posterior tip of the adipose fin is free from the dorsal surface of the body. The profile from
the dorsal spine to the snout is rounded as is the edge of the anal fin. The eye is larger and more
dorsally placed than that of the blue catfish.
The channel catfish is an adaptable fish, usually found in clear, warm lakes and moderately
large to large rivers, over clean sand, riffle, gravel or rock-rubble bottoms where it spends daylight
hours associated with some cover in quiet pool areas. It is generally not found in the muddied,
weed-choked waters that some other catfish species frequent. Channel cats, especially young fish, may be
found in fast-flowing water. Usually, channel catfish prefer deep pools and runs in rivers that have
alternating pool and riffle habitats. This is the most versatile of catfish that also found in reservoirs,
lakes and farm ponds, and even in some of the larger trout streams.
Channel cats feed mostly at night, but may forage on the bottom, where it�s dim during the
day. Channel catfish, especially young fish usually feed on the surface. Like other catfish, at night they
depend on their barbels and their sense of taste to find food. Even so, channel cats are believed to be
more of a sight-feeder than other catfishes, because of their clear-water habitat. Adults may feed almost
exclusively on other fish, but typically also consume crayfish, mollusks, immature mayflies and
caddisflies, and occasional aquatic vegetation.
Channel catfish spawn during late spring or early summer, in May to early June, when the
water temperature ranges from 75 to 85�F (22-30�C), with 80�F the optimum. Both sexes may participate in
nest site selection and construction, but most male prepares the nest, which is usually a depression or
hole in an undercut bank, or an excavated burrow under logs or rocks, sometimes in sunken, hollow logs or
abandoned muskrat holes. In clear ponds, spawning channel cats must have semi-darkened shelters, either
natural or provided. From reservoirs, channel catfish sometimes move upstream to spawn in tributary
rivers. A female channel cat may lay 2,000 to 70,000 eggs per year, depending on fish size. After
spawning, the males protect the adhesive egg mass and aerate and clean the eggs by fanning their fins. The
males also guard the hatched fish for a time. Nuptial males develop swollen lips and dorsal head
musculature, and typically do not feed during nesting. Young channel cats are insect-eaters, feeding on
mayfly nymphs, caddis larvae and midge larvae. As they grow, they switch to fish, crayfish and mollusks,
but still feed on aquatic insects, and occasionally eat plant matter.
Channel catfish are fast and powerful swimmers and provide excellent sport when taken by
angling. They are considered a high quality food fish.
This medium-sized catfish has a back and upper sides that are light blue-gray to dark
slate-gray. This shades lighter, with gray or blue markings, toward the belly, which becomes silvery or
yellow-white. The chin barbels are whitish. The caudal fin is somewhat forked, but the fin�s lobes are not
as sharply pointed as are those of the channel catfish, and may be somewhat rounded, especially in older
fish. The head is very broad. Young white catfish are slender. Older fish become heavy bodied and
robust-looking. The spine on each pectoral fin has a sawtoothed back edge. The anal fin has 25 or fewer
rays. The maximum size for the white catfish is about 24 inches.
White catfish live in channels, pools and backwaters in rivers or streams, mostly in
sluggish current over mud bottoms. They go into swift water, but not as much as channel catfish. Of all
the catfishes, white catfish are the most tolerant of salt water. They live in brackish bays and tidewater
sections of streams. They also live in lakes and river impoundments. In habitat preference, white catfish
are midway between the channel catfish, which uses firmer bottoms and swift currents, and bullheads, which
live in slow water over soft, silty bottoms.
The white catfish�s spawning habits are similar to the channel catfish, it has less of a
tendency to migrate when looking for a spawning site. Male white catfish excavate a burrow nest or use an
existing hole. The sticky egg mass is deposited there by the female. The male briefly guards the eggs and
the young. White catfish eat some plant material, but they eat mostly animal life like midge larvae and
other aquatic insects, crustaceans and fish.
The blue catfish inhabits the largest rivers and some large reservoirs. It typically occurs
in deep waters with firm substrates and considerable current. This is a large catfish, with unconfirmed
records of up to 315 lbs, and it is an excellent food and sport fish. It is pale gray to dark blue
dorsally, with a white belly, and fins with dusky margins. The posterior tip of the adipose fin is free
from the dorsal surface of the body. The back slopes steeply from the dorsal fin to the snout, giving the
head a wedge-shaped appearance, and the edge of the anal fin is straight.
Spawning of blue catfish occurs in spring, beginning as early as April and extending into
June farther north. It is thought that nesting habits are similar to channel catfish; both sexes may
participate in nest site selection and construction, but males primarily care for eggs and young.
Life span of blue catfish is unknown, but most likely exceeds 20 years. Young under 125 mm
(5 in.) feed primarily on zooplankton, while adults feed on burrowing mayflies, crayfishes, native
fingernail (Sphaeriidae) and unionid clams, introduced Asiatic clams and zebra mussels, and other fishes.
The stonecat is one of the largest members of the madtoms, a group of small fishes in the
catfish family. The madtoms are not well-known because most are little fish and hide during the day, even
burying themselves in the gravel, emerging to feed at night. The slender-shaped stonecat grows to about 12
inches long, but averages 6 to 8 inches. Its back is yellow-olive to slate-gray or blue-gray. The sides
are lighter, with yellow or pink tints. Its underparts are yellow or white. The tail is rounded or
square-looking, with a light border. The adipose fin is completely bound to the body, a trait that
distinguishes the madtoms. The upper jaw is much longer than the lower jaw. Its upper barbels are gray.
The chin barbels are white. There is a light-yellow or whitish oval-shaped spot on the rear portion of the
dorsal fin.
There are pale dorsal areas behind the head and at the posterior end of the dorsal fin. The adipose fin is
fused to the back along its entire length and the pale margin of the caudal fin is enlarged at the
posteriodorsal corner. The stonecat has no or few and weak sawteeth on the back edges of its pectoral
spines. The anal fin has 15 to 18 rays. The pectoral fin spine has 3 or 4 anterior barbs near the tip.
Habitat: The stonecat lives in rocky riffles or rapids in moderate sized warmwater creeks
and small to large warm rivers. It is also found over gravelly wind-swept and wave-stirred shoals of
lakes. The word �stone� in its name refers to where it likes to live. It is a warmwater fish and avoids
cold water that occupies gentle riffle areas with coarse substrates. It occasionally occurs both in tiny
streams and in rivers as large as the lower Mississippi.
Life history: Sexual maturity occurred at age 3 at about 3.5 in (90 mm). Stonecats spawn in
early summer, when water temperatures from 77�F(25�C) to 82�F. Females produce 200-1,200 eggs per year,
about 100-500 of which are laid in each nest in compact clusters beneath flat stones or other similar
structures. One of the parents, presumably the male, guards the nest. The opaque, yellow eggs are attached
in a compact, sticky mass to the underside of flat stones or similar objects in flowing water. The parents
guard the eggs and young for a time. Like most other catfish, stonecats feed at night and have a varied
diet, especially consuming fishes and aquatic insect larvae such as midges, caddises, stoneflies and
mayflies, as well as crustaceans and other small invertebrates.
The yellow bullhead�s natural range is the Atlantic and Gulf Coast watersheds from New York
to northern Mexico. They may grow 18 or 19 inches long, but most are much smaller. Yellow bullheads have a
long anal fin with 24 to 27 rays. Like the brown bullhead, there are 5 to 8 saw-like teeth on the back
edges of the pectoral spines. The rear edge of the tail fin is nearly straight or rounded. The posterior
tip of the adipose fin is free from the dorsal surface of the body. The armament of the pectoral spine
(the serrae) is moderately developed. Nuptial males develop swollen lips, large nuchal humps, and dorsal
head musculature; they typically do not feed during nesting periods.
They are yellow-olive to brown dorsally, shading to a lighter yellow-olive on the sides, and occasionally
may be slightly mottled. The belly is bright-yellow or whitish. The chin barbels are white or yellow.
Their fins are uniformly dusky, with a black margin typically evident on the anal and caudal fins. The
caudal fin is truncate to rounded and the chin barbels are a pale yellowish to white.
Habitat: The yellow bullhead is tolerant of low oxygen and highly silted water. It can
withstand pollution that many other fishes cannot tolerate. Yellow bullheads prefer backwaters and slow
currents in streams and rivers.They are most abundant in ponds and reservoirs, especially where there is a
mucky bottom and dense aquatic vegetation. Also live in sluggish creeks and rivers with aquatic habitats,
logs, stumps and water weeds.
Food habits are similar to those of the black bullhead, with adults feeding after dark and
utilizing a wide variety of aquatic invertebrates. Midge larvae are the predominant food item, and other
immature insects, snails, fingernail clams, crustacea, and fish are often eaten. The yellow bullhead has a
tendency to consume larger quantities of sewerage at outfalls and aquatic vegetation than has been noted
for the black bullhead.
Yellow bullheads spawn in spring, earlier than for black bullheads, usually in April and
May, with both males and females participating in nest construction. The nest can range from a shallow
depression in the muddy bottom to a two-foot-deep burrow in the stream or lake bank, usually near
protective rocks or stumps. The females produce from 1,700 to 4,300 eggs, depositing 300-700 eggs per
spawning act. The care of the sticky, yellowish-white eggs and the hatched fry is the duty primarily of
the male, which guards the young fish until they are about 2 in (50 mm) long. Nuptial males develop
swollen lips and dorsal head musculature, and typically do not feed during nesting. Yellow bullheads are
omnivores and eat aquatic insect larvae, snails, freshwater clams, crayfish, small fish and other
underwater animal life, as well as plant material. They have an excellent sense of smell, which helps them
locate food in muddy water.
The brown bullhead is the most widely distributed bullhead, found across Pennsylvania in
suitable habitat. It is native to Atlantic and Gulf Coast watersheds, from eastern Canada to Alabama. It
was also originally found in the Great Lakes system, Hudson Bay and the Mississippi River watershed. It
has also been widely introduced. Its species name �nebulosus� means �clouded,� referring to the fish�s
mottled sides.
Brown bullheads average 12 to 15 inches. The upper part of the head, back and sides are dark
to light yellow-brown or olive-brown, shading to grayish white or yellowish white on the belly. The sides
have brown or black mottling. The brown bullhead�s chin barbels are dark, grayish black, but may have
whitish color at the base. These help to distinguish the brown bullhead from the black bullhead, which is
known from a few northwestern Pennsylvania counties. The black bullhead�s chin barbels are all black. The
brown bullhead�s caudal fin is square-tipped, or slightly rounded. Its strong pectoral fin spines have
five to eight sawlike teeth on their rear edges. The anal fin has 18 to 24 rays, usually 22 or 23.
Brown bullheads live in several habitat types, but they are found mostly in ponds and the
bays of larger lakes, and in slow-moving sections and pools of warmwater streams. They are
bottom-dwellers, usually living over soft mud or muck, where there is plenty of underwater vegetation.
Brown bullheads can sometimes be found as deep as 40 feet. They are tolerant of very warm water
temperatures, high carbon dioxide and low oxygen levels, and levels of pollution that other fish cannot
tolerate.
Brown bullheads spawn in late spring, May to June, when water temperatures reach 70�F,
usually in the daytime. Both males and females participate in nest construction, which can be a shallow
saucer on the bottom mud or sand, or among roots of aquatic plants, near the protection of stumps, rocks
or downed trees around the shoreline or in coves, or in the mouth of a creek. Nests can also be excavated
holes or natural burrows, under sunken boards and logs, and in hollow stumps. The water depth for spawning
ranges from 6 inches to several feet.
The females produce from 2,000 to 13,000 cream-colored, mucous-covered eggs. Sometimes one
or both parents eat some of the eggs. Both male and female brown bullheads cooperate in protecting the
nest, eggs and young. The parents fan and stir the eggs with their fins, aerating them sometimes cleaning
them inside their mouth. Hatched brown bullheads are pitch-black and may be mistaken for tadpoles. One or
both parents shepherd the loose ball of fry for several weeks, until the young are about one inch long.
Like other catfish, brown bullheads are active mostly at night, when their sensitive barbels
help them find food in the darkness. They are omnivorous bottom-feeders and eat a wide variety of plant
and animal material, including aquatic insects and larvae, worms, minnows and other small fish, crayfish,
snails, freshwater clams and even algae. Brown bullheads are able to exist on atmospheric air for a time.
They can remain alive for hours if kept moist when they are out of the water.
Black bullheads occur in quiet waters over soft bottoms in habitats ranging from farm ponds
to lakes and reservoirs, and small creeks to large rivers. They are dark brown to nearly black with a
yellow to white underside. The fins are characterized as having dark membranes that contrast sharply with
paler fin rays. The posterior tip of the adipose fin is free from the dorsal surface of the body. The
caudal fin is truncate or rounded, and the tip of the dorsal lobe of the caudal fin is never white. The
chin barbels have dark pigment and the sides of this bullhead are never mottled. The sharp projections
(serrae) on the posterior edge of the pectoral spine are weak.
Adults are very secretive during daylight hours, feeding almost exclusively after dark, and
are seldom seen or caught in rivers and streams until after dusk. Adults feed on a wide variety of aquatic
invertebrates, while juveniles feed predominantly on ostracods, amphipods, and copepods.
The nest, consisting of a hollowed out depression in the gravel substrate, was constructed by the female
using her pelvic and anal fins to sweep out the depression, and pushing larger particles out of the
depression with her snout. The male remained near the nest during and after its construction, and
courtship was apparently initiated by the female. After several pairings, spawning was noted by a distinct
quivering of the female. The female guarded the nest and eggs during the first day following spawning,
with the male assuming this role thereafter. Eggs hatched in 5-10 days, and free-swimming young remained
in a tight school, typically guarded by the male, for about 2 weeks, at which time they had attained 25 mm
(1 in.) total length. Nuptial males develop swollen lips and dorsal head musculature, and typically do not
feed during nesting. The females produce from 2,500-3,800 eggs. Young feed primarily on ostracods,
amphipods, and copepods, with much feeding associated with mid-day schooling activity. Juveniles fed
mostly at dawn or dusk. Adults fed almost exclusively after dark and utilized a wide variety of aquatic
invertebrates. Midge larvae were the predominant food item in all studies reported, and other immature
insects, snails, fingernail clams, crustacea, and fish were often eaten. Consumption of sewerage at
outfalls and aquatic vegetation has been noted.
Smoky Madtom
The smoky madtom is a small fish (maximum size 3 in.) that is currently only known from a
4.2-km portion of Citico Creek, Monroe County, Tennessee. The smoky madtom is a very secretive species
that in summer and fall inhabits areas transitional between pools and riffles with depths of about 25 cm
and gravel substrates interspersed with rounded cobbles and small boulders. In the winter and spring it
inhabits gentle runs and pools. The madtom is colored brown, with pale yellow dorsal saddles that do not
extend onto the sides. The adipose fin is fused to the back along its entire length and has a broad dark
bar that extends to or nearly to the dorsal margin. The caudal fin has vague pale and dark vertical bands.
The pectoral fin spine has the anterior armature (serrae) virtually absent and the posterior serrae
moderately developed. Their anal fin has 12-14 rays, soft pectoral fin has 8 rays, pelvic fin has 7-9 rays
(usually 8) and total caudal fin has 42-49 rays. They also have usually 2 internasal pores while
preoperculomandubular canal has 11 pores.
Madtoms may actually bury themselves under several inches of gravel and rely on interstitial
water during daylight hours. The madtoms, like the other ictalurids, are presumably opportunistic feeders,
preying on aquatic invertebrates and small fishes as well as scavenging. Feeding is primarily nocturnal.
The smoky madtom differs from the yellowfin madtom, Noturus flavipinnis, in lacking
extensive dark pigment on the dorsal fin rays and dark blotches, or bars, on the adipose and caudal fin
bases. The dorsal fin of the smoky madtom has no dark pigment except for brown on the spine, and only
vague pale and dark vertical bands on the caudal fin. Small Ictalurus have a forked tail, while madtoms
have a rounded or truncate tail; young Ameiurus and Pylodictis might be mistaken for one of the madtom
species, but the free posterior end of the adipose fin is apparent even in young Ameiurus and Pylodictis
(the adipose fin is fused to the back along its entire length in madtoms).
Yellowfin Madtom
The yellowfin madtom is a small fish (maximum size 5.25 in.) that is currently found
predominantly in a 1.5-km reach of Citico Creek in Monroe County, Tennessee. It is colored yellow dorsally
and white ventrally. Its nape area is dark, and there are dark blotches beneath the dorsal fin origin and
behind the dorsal fin. The adipose fin is fused to the back along its entire length and a dark vertical
band runs through the middle of the adipose fin and extends onto the adipose fin base. The dorsal and
caudal fins are boldly patterned with pale and dark areas. A black bar is present at the base of the
caudal fin. Both anterior and posterior armament of the pectoral spine is well developed. Their anal fin
has 14-16 rays, soft pectoral fin has 7-8 rays, pelvic fin has 8 rays and total caudal fin has 54-63 rays,
4-8 gill rakers. They also have usually 2 internasal pores while preoperculomandubular canal has 10-11
pores.
The yellowfin madtom is very difficult to see or collect in streams in the daytime, but is
easily seen or captured in open areas of pools while snorkeling at night. When accumulations of leaves are
available in pool areas, yellowfin madtoms, especially smaller individuals, use these areas for cover.
Madtoms may actually bury themselves under several inches of gravel and rely on interstitial water during
daylight hours. The madtoms, like the other ictalurids, are presumably opportunistic feeders, preying on
aquatic invertebrates and small fishes as well as scavenging. Feeding is primarily nocturnal.
Spawning occurs from late May to mid-July, with water temperatures of 65-70�F (18-21�C).
Females may spawn at least twice per season, since their complement of mature eggs is about twice the
average number found per nest. Males guard clutches of 30 to over 100 eggs in cavities under slab rock.
Young reach total lengths of about 2 in (50 mm) after one summer's growth, and sexual maturity is attained
at about 4 in (100 mm) total length. Life span is estimated to be 3-4 years.
The yellowfin madtom has extensive dark pigment on the dorsal fin rays and dark blotches or
bars on the adipose and caudal fin bases. It is distinguishable from the smoky madtom, Noturus baileyi,
which has no dark pigment on the dorsal fin except for brown pigment on the spine, and only vague pale and
dark vertical bands on the caudal fin. Small Ictalurus have a forked tail, while madtoms have a rounded or
truncate tail; young Ameiurus and Pylodictis might be mistaken for one of the madtom species, but the free
posterior end of the adipose fin is apparent even in young of these larger catfish (the adipose fin is
fused to the back along its entire length in madtoms).
Identification of Channel Catfish and Blue Catfish
Channel Catfish
Body with dark spots (spots may be absent in large adults).
Outer margin of anal fin rounded, and anal fin with 24 to 29 rays.
Blue Catfish
Body without dark spots.
Outer margin of anal fin straight, and anal fin with 30 to 36 rays.
Black Bullhead with Yellow Bullhead
The dark chin barbels and the sharply contrasting black membranes and paler rays of the caudal and anal
fins of the black bullhead are usually sufficient to separate it from the yellow bullhead, which has
uniformly dusky fins with a black margin on the caudal and anal fins, and non-pigmented chin barbels. The
several madtoms in the Park look similar to bullheads, but madtoms have the adipose fin fused to the body
along its entire length, while the posterior tip of the adipose fin of bullheads is free.
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