Life-history Attributes of the Imperiled Frecklebelly
Madtom, Noturus munitus (Siluriformes: Ictaluridae),
in the Cahaba River System, Alabama
Micah G. Bennett, Bernard R. Kuhajda, and Jenjit Khudamrongsawat
Southeastern Naturalist, Volume 9, Issue 3 (2010): 507–520
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2010 SOUTHEASTERN NATURALIST 9(3):507–520
Life-history Attributes of the Imperiled Frecklebelly
Madtom, Noturus munitus (Siluriformes: Ictaluridae),
in the Cahaba River System, Alabama
Micah G. Bennett1,2,*, Bernard R. Kuhajda1, and Jenjit Khudamrongsawat1,3
Abstract - Noturus munitus (Frecklebelly Madtom) is a diminutive catfish with a disjunct
distribution across the southeastern United States in large rivers and tributaries
of the Mobile Basin and Pearl River drainage. Its distribution has contracted since
extensive river modification began throughout its range in the 1960s, and it is likely
extirpated from the Alabama River. We collected 242 specimens of N. munitus from a
gravel island in the Cahaba River on the Coastal Plain in Alabama from May 2005 to
March 2007 to examine life-history characteristics. Adults were associated with fast
flow over large gravel at depths of 0.5–1.0 m. Young (<23 mm) were found at water
depths of 0.4–0.5 m. Gonad development indicated a reproductive season from May
to August, with collection of young-of-the-year in June and July supporting a mid- to
late-summer spawn. Stomach content analysis revealed a diet similar to other Noturus
species and dominated in volume by Baetidae nymphs (31.2%), Hydropsychidae
larvae (20.3%), and Simuliidae larvae (19.7%). Some seasonal and sex differences
in diet were apparent. Relative fecundity data indicate that N. munitus is one of the
most fecund madtoms of the subgenus Rabida (mean of 30.6 mature oocytes) studied
thus far. Few males were found in riffles during summer, and no young were found
in riffles outside summer, indicating potential sex and size differences in seasonal
habitat use. This knowledge is important for conservation of the species.
Since Taylor’s (1969) revision of the genus Noturus, there has been a
major effort to close gaps in our knowledge of madtom biology, and much
information is known for the genus as a whole (reviewed in Burr and
Stoeckel 1999). As a group, the North American genus is imperiled due to
river modification and other human impacts to aquatic ecosystems (Burr and
Stoeckel 1999, Jelks et al. 2008). However, several species still have no or
only partial life-history data published.
One of these imperiled species is Noturus munitus Suttkus and Taylor
(Frecklebelly Madtom), a robust, boldly patterned member of the monophyletic
saddled madtom subgenus Rabida (Hardman 2004, Near and
Hardman 2006, Suttkus and Taylor 1965). Noturus munitus has a disjunct
distribution across the southeastern United States in the Mobile Basin and
1University of Alabama Ichthyological Collection, Department of Biological Sciences,
Box 870345, Tuscaloosa, AL 35487-0345. 2Current address - Department of
Biology, Saint Louis University, 3507 Laclede Avenue, St. Louis, MO 63103-2010.
3Current address - Department of Biology, Faculty of Science, Mahidol University,
Bangkok, Thailand. *Corresponding author - firstname.lastname@example.org.
508 Southeastern Naturalist Vol. 9, No. 3
Pearl River drainage (Fig. 1). It occupies large and medium-sized rivers
mostly on the Gulf Coastal Plain, with an additional population in upland
areas in the upper Coosa River (Conasauga and Etowah systems) in Georgia
and Tennessee, which is considered an undescribed form (Boschung and
Mayden 2004, Butler and Mayden 2003, Jelks et al. 2008, Neely et al. 1998,
Suttkus and Taylor 1965). Although once fairly abundant in appropriate
habitat, N. munitus has declined rapidly since the mid-1960s, when river
modification began throughout its range. The species is now reliably found
in high numbers in only a few locations (Bennett et al. 2008, Boschung and
Mayden 2004, Piller et al. 2004, Shepard 2004) and is considered threatened
with extinction (Bennett et al. 2008, Jelks et al. 2008). Trauth et al. (1981)
examined aspects of reproductive development and population structure in
Mississippi, and Miller (1984) conducted a detailed study of the diet in a
population of N. munitus from the Tombigbee River system; however, the
species’ overall rarity, combined with its nocturnal habits and preference for
difficult-to-sample large-river gravel shoals, has contributed to the lack of
detailed life-history information for N. munitus.
Figure 1. Current and historical distribution of N. munitus. Gray shading represents
historic range. Hatching represents current distribution. 1. Pearl River drainage—a)
Bogue Chitto River, b) lower Pearl River and tributaries; 2. upper Tombigbee River
drainage—a) East Fork, b) Buttahatchie River, c) lower Luxapallila Creek, d) Sipsey
River; 3. Alabama and Cahaba river drainages—a) lower Cahaba River; 4. Etowah
River system—a) upper Etowah River; 5. Conasauga River system—a) middle Conasauaga
River. Black dot is study site on Cahaba River.
2010 M.G. Bennett, B.R. Kuhajda, and J. Khudamrongsawat 509
One of the few drainages in which N. munitus persists in abundance
is the Cahaba River in central Alabama, which has escaped large-scale
damming and other anthropogenic modifications. The Cahaba River flows
approximately 307 km (191 mi) through north-central Alabama, beginning
in the Valley and Ridge physiographic region near Birmingham and flowing
through the Coastal Plain into the Alabama River near Selma (Boschung and
Mayden 2004). The river has escaped major channelization and maintains
numerous gravel islands and shoals throughout its lower Coastal Plain section,
which provide habitat for N. munitus and other large-river specialists.
Here, we provide information on the age, diet, habitat, and reproduction of
N. munitus from the Cahaba River to add to the growing body of knowledge
of madtom ecology and to aid in our understanding and ability to protect this
Two hundred forty-two specimens of N. munitus were collected and
formalin-fixed during nighttime sampling from May 2005 to March 2007
from a gravel island on the Cahaba River (32.66500°N, -87.24083°W) using
a 4.6- x 1.2-m mesh seine and a backpack electrofisher. Measurements
of habitat included flow rate (estimated by timing a floating object for a
distance of 10 m), depth (measured using meter stick), and substrate. No
collections were made from January–March 2006 and August–January
2006–07 due to high water or because adequate samples were collected the
After transfer to 70% ethanol, standard length (SL) was measured to
the nearest 0.1 mm using dial calipers, and specimens were blotted dry
to determine wet body mass to the nearest 0.01 g. Sex of individuals was
determined by internal examination of gonads: testes were white and
lobed (cf., Mayden and Burr 1981, Sneed and Clemens 1963), and ovaries
consisted of spherical white, orange or amber oocytes (cf., Mayden and
Burr 1981). Gonads were weighed to the nearest 0.001 g and a gonadosomatic
index (GSI) was calculated using the formula ([gonad weight x
1000] / somatic body weight [i.e., after removal of abdominal organs
except the air bladder]) following Mayden and Burr (1981). Oocyte maturity
stage was determined using classification systems of both Baker and
Heins (1994) and Mayden and Burr (1981). Oocytes from mature, ripening,
and ripe ovaries (Baker and Heins 1994) and mature or potentially
mature ovaries (Mayden and Burr 1981) were counted, and the diameters
of three oocytes from each ripening and ripe individual were measured to
the nearest 0.01 mm.
A sub-sample of individuals, which included the two largest males, the
two largest females, and the two smallest individuals, was selected for diet
analysis from each season (spring = April–May; summer = June–August;
510 Southeastern Naturalist Vol. 9, No. 3
fall = September–November; winter = December–February). This subsample
was supplemented with intermediate-sized fish to increase sample
sizes for seasonal and other comparisons for a total of 91 stomachs.
Stomach contents were identified to family when possible, the proportion
of each type of food item was determined, and the volume of each type of
food item was approximated following Winemiller (1990). Percent of total
volume of diet items was compared between sexes and two size classes
(large [>42 mm SL] and small [23–40 mm SL]), and among seasons. We
tested for significant deviations from equal sex ratio using a chi square
test in Excel (Microsoft Corp., Seattle, WA). Age classes were visually
estimated by examining length-frequency data for various time periods of
Habitat and associated species
Several large-river specialists were frequently collected with
N. munitus, including Macrhybopsis sp. cf. aestivalis, an undescribed
Speckled Chub, Macrhybopsis storeriana (Kirtland) (Silver Chub), Notropis
uranoscopus Suttkus (Skygazing Shiner), Crystallaria asprella (Jordan)
(Crystal Darter), Percina lenticula Richards and Knapp (Freckled Darter),
and Percina vigil (Hay) (Saddleback Darter) (Boschung and Mayden 2004,
Shepard 2004). Adult madtoms were collected in swift current (mean = 1
m/sec) over large gravel, sometimes with sticks and leaf detritus, at depths
of 0.5–1.0 m. Young-of-the-year madtoms (<23 mm) collected in June and
July were associated with slower current in shallower water (0.4–0.5 m).
Noturus munitus was not collected over sand or associated with aquatic
vegetation. On two occasions, adult madtoms were collected within partially
buried mussel shells.
Reproductive development based on GSI values increased rapidly in
March for females, showing sustained high gonad-to-body weight ratios
during the spring. Their GSI values (range = 1.6–271.1) peaked in June, followed
by a substantial drop in July (Fig. 2). Male GSI values (range = 0.0–
8.8) peaked in May (Fig. 3). For all females, SL was significantly correlated
with gonad weight based on linear regression (R² = 0.64 for log-transformed
values, P < 0.001).
Of the 123 females examined for reproductive development, 15 were
early-maturing, 64 were late-maturing, 34 were mature, 8 were ripening,
and 2 were ripe based on the classifications of Baker and Heins (1994).
According to the classifications of Mayden and Burr (1981), all earlymaturing
and late-maturing individuals were immature, and there were 32
potentially mature and 12 mature individuals. Mature oocytes were usually
smaller and cream, opaque-yellow, or yellow. Ripening and ripe oocytes
2010 M.G. Bennett, B.R. Kuhajda, and J. Khudamrongsawat 511
were large (range = 1.6–2.5 mm, mean = 2.9 mm, n = 30) in diameter and
amber or orange in color; ripe ovaries were darker towards the urogenital
opening (cf., Heins et al. 1992). All fish with ripening and ripe oocytes
also contained a second distinct size class of latent white oocytes less than
Figure 3. Mean gonadosomatic index by capture date for male N. munitus (Frecklebelly
Madtom). Note gaps in sequence from June–August 2005, December
2005–April 2006, and July 2006–February 2007 due to no samples or absence of
mature individuals. Error bars represent ± 1 standard error.
Figure 2. Mean gonadosomatic index by capture date for female N. munitus
(Frecklebelly Madtom). Note gaps in sequence from June–August 2005, December
2005–April 2006, and July 2006–February 2007 due to no samples or absence of
mature females. Error bars represent ± 1 standard error.
512 Southeastern Naturalist Vol. 9, No. 3
0.1 mm in diameter (cf., Baker and Heins 1994, Mayden and Burr 1981).
One individual with mature oocytes was found in November; however,
most mature individuals were found from March through June. Individuals
with ripening oocytes were found from April through June and, along with
ripe individuals, had the highest GSI values. The only two ripe individuals
were found in June.
All 10 ripening and ripe individuals and nine of the larger mature individuals
from April through June were used to calculate fecundity (Baker and
Heins 1994). Total number of oocytes from both ovaries (absolute ovarian
fecundity, Burr and Stoeckel 1999) ranged from 70–171 in the 19 females
examined (mean = 119). Relative fecundity (mature oocytes per g body
weight) ranged from 21–39 (mean = 31). Even though the mature stage encompassed
a broad range of oocyte sizes (Baker and Heins 1994), restricting
fecundity measurements to ripening and ripe females (the mature of Mayden
and Burr 1981) did not produce a significantly different mean value or range.
The smallest mature female was 41.1 mm SL, which corresponds to the
approximate 2+ age class. The total number of oocytes increased with SL
for all females (R² = 0.39, P = 0.004), but the relationship was stronger for
ripening and ripe females (R² = 0.55, P = 0.014). The sex ratio for the entire
Table 1. Stomach contents for 91 specimens of N. munitus (Frecklebelly Madtom) by mean
percent volume and mean percent total number.
Food items Mean % volume Mean % composition by number
Chironomidae 2.3 9.0
Simuliidae 19.7 40.8
Tipulidae 0.3 0.6
Baetidae 31.2 35.4
Heptageniidae 0.1 0.4
Isonychiidae 6.0 0.4
Tricorythidae 0.5 0.5
Unknown 3.5 0.8
Perlidae 2.4 0.3
Perlodidae 5.0 0.5
Polycentropodidae 1.3 1.1
Hydropsychidae 20.3 9.4
Hydroptilidae 0.3 0.2
Psychomyiidae 0.04 0.1
Elmidae 0.2 0.2
Coryxidae 0.5 0.2
Other 5.4 0.1
2010 M.G. Bennett, B.R. Kuhajda, and J. Khudamrongsawat 513
sample was not significantly different from 2 females:1 male based on a
chi-square test (1.74 females/male, P = 0.74). This pattern was the same for
individuals in late spring through summer (May–August) (2.8 females/male,
P = 0.26), but in fall (September–December), the ratio was not significantly
different from 1:1 (1.5 females/male, P = 0.09).
Diet analysis showed Baetidae nymphs (31%), Hydropsychidae larvae
(20%), and Simuliidae larvae (20%) provided most of the food volume for
N. munitus (Table 1). These three groups maintain top position by percent
of total number (35, 9, and 41% respectively), although the order of relative
importance changes. Chironomidae made up a higher proportion of diet by
number than by volume (Table 1). An item of interest in a stomach (placed
in the “other” category in Tables 1–3) was a larval ictalurid.
Chironomidae made up a much larger portion of the diet in winter
(21%) than in other seasons (≤3%) (Table 2). Baetidae nymphs made up
56% of the diet volume in spring, but only 14–22% in other seasons. Simuliidae
larvae made up 38% of the diet volume in fall, but only 1–17% in
Table 2. Stomach content analysis by season for 91 specimens of N. munitus (Frecklebelly
Madtom). %V = percent volume, %N = percent by number
Spring (n = 25) Summer (n = 22) Fall (n = 22) Winter (n = 22)
Food items %V %N %V %N %V %N %V %N
Chironomidae 3.3 10.5 1.5 10.6 1.1 2.7 21.2 63.3
Simuliidae 8.2 22.0 17.4 49.9 38.1 59.8 1.0 2.5
Tipulidae 0.0 0.0 0.53 1.3 0.45 0.54 0.17 1.3
Baetidae 55.9 60.1 13.8 18.1 20.2 21.0 21.7 13.9
Heptageniidae 0.92 0.39 0.40 0.25 0.0 0.0 15.2 5.1
Isonychiidae 10.3 0.58 0.0 0.0 8.9 0.54 0.0 0.0
Tricorythidae 0.92 0.78 0.67 0.76 0.0 0.0 0.0 0.0
Unknown 0.0 0.0 6.8 1.8 4.5 0.81 0.0 0.0
Perlidae 1.1 0.19 0.0 0.0 2.5 0.54 9.9 1.3
Perlodidae 0.0 0.0 15.4 1.8 0.0 0.0 0.0 0.0
Polycentropodidae 0.0 0.0 0.0 0.0 0.89 0.0 0.0 0.0
Hydropsychidae 14.3 4.5 25.3 12.7 21.7 12.4 21.2 11.4
Hydroptilidae 0.65 0.19 0.0 0.0 0.37 0.27 0.0 0.0
Psychomyiidae 0.0 0.0 0.13 0.25 0.0 0.0 0.0 0.0
Other 1.3 0.19 3.1 2.5 0.89 0.81 0.33 1.3
Elmidae 0.40 0.19 0.0 0.0 0.0 0.27 0.0 0.0
Coryxidae 1.4 0.39 0.0 0.0 0.0 0.0 0.0 0.0
Other 1.3 N/A 14.9 N/A 0.30 0.27 9.3 0.0
514 Southeastern Naturalist Vol. 9, No. 3
other seasons. Isonychiidae nymphs appeared in the diet only in spring
and fall, and Perlodidae larvae were found only in summer. Percentage of
empty stomachs was greatest in spring (24%) and winter (23%) and low in
summer and fall (5%).
Diet comparison between 17 large and 17 small individuals indicated a
heavier reliance on Chironomidae by small madtoms (3% of diet volume
versus 1% in large individuals) and a greater diversity of prey items consumed
by large individuals. Small individuals consumed a total of 10 taxa
compared to 14 taxa consumed by large individuals. Examination of male
and female stomach contents (Table 3) revealed more utilization of Simuliidae
(32%) and Isonychiidae (7%) by volume in males, but both sexes heavily
utilized Baetidae (32%) and Hydropsychidae (males 17%; females 24%).
Females consumed a larger total volume (1416 μL) than an equal number of
males (810 μL).
Length-frequency histograms were somewhat difficult to interpret due to
low sample size for some seasons and the absence of individuals <37 mm
from October to December 2005 and should be taken as only preliminary
Table 3. Stomach content analysis by sex for 91 specimens of N. munitus (Frecklebelly Madtom).
Food items % volume % by number % volume % by number
Chironomidae 2.8 12.3 2.1 10.9
Simuliidae 31.8 45.1 13.8 34.8
Tipulidae 0.25 0.51 0.39 0.65
Baetidae 32.2 31.3 32.3 37.0
Heptageniidae 1.6 0.51 0.71 0.52
Isonychiidae 7.4 0.34 0.21 0.39
Tricorythidae 0.74 0.68 0.42 0.39
Unknown 4.9 0.85 2.9 0.65
Perlidae 0.37 0.17 3.7 0.39
Perlodidae 0.0 0.0 8.2 0.91
Polycentropodidae 0.99 1.0 1.6 1.0
Hydropsychidae 16.5 6.8 23.6 11.4
Hydroptilidae 0.0 0.0 0.53 0.26
Psychomyiidae 0.12 0.17 0.0 0.0
Elmidae 0.0 0.0 0.25 0.26
Coryxidae 0.0 0.0 0.78 0.26
Other 0.25 0.17 8.6 0.12
2010 M.G. Bennett, B.R. Kuhajda, and J. Khudamrongsawat 515
hypotheses for age structure. In the April–June histogram (Fig. 4) and the
July–September histogram (Fig. 5), the one with the largest sample size,
there appear to be approximately three size classes. Most of the young-ofthe-
year (0+) appear to have grown quickly, with a mode around 29 mm
(17–31 mm), and a second mode of around 34 mm may correspond to age
1+ fish (31–43 mm), but the upper boundary of this class is difficult to
define (Fig. 5). The 2+ is difficult to assign due to lack of specimens from
49–66 mm, but may be represented by the mode of 53 mm in the October
to December 2005 histogram, with possible 3+ individuals greater than or
equal to 58 mm (Fig. 6). The largest specimen collected was a 66.8 mm male.
Figure 5. Length-frequency histogram for N. munitus (Frecklebelly Madtom) collected
from July–September 2005 and 2006. Bars represent estimated age classes.
Figure 4. Length-frequency histogram for N. munitus (Frecklebelly Madtom) collected
from April–June 2005 and 2006. Bars represent estimated age classes.
516 Southeastern Naturalist Vol. 9, No. 3
Young-of-the-year individuals (13–23 mm SL) were first collected in late
June of 2005 and 2006 and were collected through late July. Most individuals
collected were in the 1+ age class.
Our data rank N. munitus as highly fecund compared to other members of
the subgenus Rabida. Based on data compiled in Burr and Stoeckel (1999)
and adding data from Bulger et al. (2002), absolute fecundity in Rabida
ranges from 14 to 340 (mean = 89.7) and relative fecundity, which is only
available for 5 of the 18 extant Rabida species, ranges from 11.7 to 43.1
(mean = 20.5). The mean absolute fecundity of N. munitus (119.4) is about
average for Rabida, but its mean relative fecundity (30.6), preferable for
comparing species (Mayden and Walsh 1984), is among the highest known
for the subgenus, with higher values reported only from a subspecies of the
Least Madtom, N. hildebrandi lautus Taylor (Mayden and Walsh 1984). Noturus
munitus is intermediate in mean absolute fecundity between two of its
closest relatives, N. placidus Taylor (Neosho Madtom) (41.5; Bulger et al.
2002) and N. stigmosus Taylor (Northern Madtom) (191; Burr and Stoeckel
1999) (Hardman 2004, Near and Hardman 2006).
Reproduction and diet are similar to those for other madtom species.
Noturus munitus likely spawns in mid-late summer and appears to reach
reproductive maturity during the second summer of life, as has been reported
for most madtom species not attaining 100 mm SL (Burr and Stoeckel
1999). Based on current knowledge of diet (Miller 1984), N. munitus is an
opportunistic insectivore feeding on a variety of aquatic insect larvae. Our
Figure 6. Length-frequency histogram for N. munitus (Frecklebelly Madtom) collected
from October–December 2005. Bars represent estimated age classes.
2010 M.G. Bennett, B.R. Kuhajda, and J. Khudamrongsawat 517
data for N. munitus diet are similar to results from Miller’s (1984) study on
a Tombigbee River population which found only slight changes in important
prey taxa through time and between sexes. The few seasonal changes in
diet probably reflect differences in prey availability, as has been previously
found for N. munitus and several other madtom species (Burr and Stoeckel
1999, Miller 1984).
Variations in sex ratio, presence of young-of-the-year, and a sharp drop
in female GSI from June to July, provide important clues to seasonal habitat
shifts in N. munitus at our sampling site. While no nests of N. munitus
have been found, different sex ratios in summer (2 females to 1 male) versus
fall (1:1), as well as lack of adults in summer, may result from males
moving to pools (where wading sampling is not possible) to prepare nesting
sites while females remain more evenly dispersed among different habitats
(Burr and Stoeckel 1999, Clugston and Cooper 1960, Mayden and Burr
1981). Higher male mortality, which could also explain unequal sex ratios,
is unlikely because males made up a greater portion of the larger size classes
(Clugston and Cooper 1960, Mayden and Walsh 1984). Lack of small
madtoms in fall collections (all were ≥34 mm) may indicate that young-ofthe-
year spend several months in slow-moving, deep-water habitats after
hatching. The sharp break in female GSI values from June to July could
result from ripe females moving to male-guarded nesting sites in pools, out
of the reach of our collecting gear. This explanation is further supported by
the fact that all females collected in July 2006 were less than 31 mm SL,
smaller than the youngest mature female collected during the study (41.1
mm SL). These data combined with the presence of young-of-the-year
in late June may suggest spawning and nesting in pools in June and July.
Brewer et al. (2008) found similar results with N. flavus Rafinesque (Stonecat),
in a Missouri river, with adults becoming rare in May and June and
returning in July, and suggested that histological techniques, rather than
GSI, may be more useful in fishes that move to difficult-to-sample habitats
for spawning because it would reveal internal morphological and physiological
changes associated with spawning in individual fish and would
thus require fewer samples.
Of the 29 described Noturus species, more than 50% are considered
vulnerable, imperiled, or extinct, and many of the undescribed forms are
likely in need of conservation action due to small ranges and increasing
anthropogenic threats (Burr and Stoeckel 1999, Jelks et al. 2008). We still
lack a basic understanding of the biology of some of the most critically
imperiled madtoms due to their rarity (e.g., N. crypticus Burr, Eisenhour,
and Grady [Chucky Madtom]; N. fasciatus Burr, Eisenhour, and Grady
[Saddled Madtom]; Noturus stanauli Etnier and Jenkins [Pygmy Madtom];
N. taylori Douglas [Caddo Madtom]). While phylogeny can be used to
infer traits of closely related species, there are still gaps in our understanding
of evolutionary relationships and important aspects of reproductive
518 Southeastern Naturalist Vol. 9, No. 3
biology. For example, nesting biology and habitat has yet to be determined
for N. munitus, and although these data could potentially be inferred from
close relatives N. placidus and N. stigmosus (Hardman 2004), there is also
very little information for these species (Burr and Stoeckel 1999, Holm
and Mandrak 2001, MacInnis 1998). Successful conservation of aquatic
biodiversity in the future will depend on accurate knowledge of species’
habitat and life-history traits, the communities and ecosystems they occupy,
recognition and description of evolutionary diversity within currently
described species, and our ability as scientists to educate and involve more
citizens in research and conservation efforts (Angermeier 2007, Mayden
and Wood 1995).
We thank J.H. Howell, A. Waggoner, N. Putman, C. Fluker, B.L. Fluker, G. Hubbard,
A. Rypel, T.B. Kennedy, L. Robinson, M. Sandel, P. Hegji, and R. Butler for
much-needed field assistance. The University of Alabama Ichthyological Collection
(UAIC) granted access to all specimens. Fieldwork was performed under permits
from the Alabama Department of Conservation and Natural Resources and the University
of Alabama Animal Care and Use Committee. A generous grant from the
Howard Hughes Medical Institute to the University of Alabama partially supported
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madtom catfish, Noturus hildebrandi (Bailey and Taylor 1950), with a review of
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