Content uploaded by Jan Jeffrey Hoover
Author content
All content in this area was uploaded by Jan Jeffrey Hoover on Feb 19, 2016
Content may be subject to copyright.
he paddlefish, Polyodon spathula, is unlike any
other fish found in the fresh waters of the northern
hemisphere (Fig. 1). Its large size and surface-
dwelling habits make it readily observable. Its
shark-like appearance and prominent bill, or rostrum, render
it instantly recognizable and long-remembered. Small wonder,
then, that the paddlefish was discovered and described not
once, but repeatedly, by explorers and naturalists, and will
probably continue to be described and pondered over well
into the 21st century.
Water Demons and Piexe Palla
Undoubtedly, the earliest observations of paddlefish
were those by American Indians. Medium to large-sized fish
(2-25 kg) were almost certainly encountered by Indians fishing
floodplain pools and large lakes. Very large specimens (> 40
kg), which usually occur in the main channel of big rivers or
in deep, flooded backwaters, were probably less familiar,
especially when viewed at some distance from shore, and may
have been interpreted as different creatures. Several tribes in
the lower Mississippi Valley (e.g., Quapaws) and Great Lakes
Basin (e.g., Hurons) had legends about demons that lived in
the water and which were usually seen as evil omens
(Meurger and Gagnon, 1988). These monsters were often
described as having long, scaleless bodies, large mouths, and
a great horn or bone protruding from the forehead. The
prevalence of such “horned serpent” myths within the range
of paddlefish, and during a time when large individuals
would be comparatively common, seems hardly coincidental.
American Currents Vol. 26, No. 21
Horned Serpents, Leaf Dogs, and
Spoonbill Cats: 500 Years of
Paddlefish Ponderings in North America
Jan Jeffrey Hoover, K. Jack Killgore, and Steven G. George
U. S. Army Engineer Research and Development Center, Waterways Experiment Station,
3909 Halls Ferry Road, Vicksburg, MS 39180-6199
THernando de Soto has been suggested as the first
European to “discover” paddlefish when he crossed the
Mississippi River (Carlander, 1954). De Soto himself may or
may not have seen paddlefish in the Mississippi, but one of
his party, a high-ranking professional soldier, published such
a description in 1557 (D. Sheppard, pers. comm.). “A
Gentleman from Elvas” wrote of the fishes caught by local
Indians using nets in the Wabash River near Terre Haute,
Indiana in June 1541 (Clayton et al., 1996). Species included
large catfish (probably blue catfish, Ictalurus furcatus), suckers
(probably buffalo, Ictiobus spp.), and a very unusual fish the
Portuguese called “piexe palla.” This fish had a “snout a cubit
in length . . . the tip of its upper lip . . . shaped like a shovel.”
Appropriately named by the explorers, “piexe palla” means
“shovel fish” or “paddle fish.”
Two decades after the de Soto expedition, another long-
snouted fish was reported by John Sparke the Younger who,
in 1564, sailed aboard the Jesus of Lubeck under Captain (later
Sir) John Hawkins and who kept the ship’s register. Sparke
was a dutiful reporter and a competent naturalist. He recorded
fantastic accounts related to him by early New World settlers
(such as unicorns and three-headed serpents), but he himself
made conservative observations of fish, reptile, and bird life
(Hakluyt, 1810). Near the mouth of a Florida river, he
recorded “great fish, some the length of a man and longer,
being of bigness according, having a snout much like a sword
a yard long.” According to zoologist Norman John Berrill,
these fish were paddlefish (Berrill, 1952). “Florida” at the
time comprised most of the southeastern United States
(Williams, 1986) and would certainly have included part of
Spring (May) 2000 American Currents 2
the geographic range of the paddlefish such as the Mobile
Bay drainage. Sparke, however, was writing about observations
in the St. Johns River (L. Williams, pers. comm.), an Atlantic
drainage far removed from any known records of paddlefish
populations in Gulf Slope drainages (Burr, 1981). Paddlefish
may have had a more extensive distribution in the 16th century
than they do now, but a more likely explanation is that
Sparke’s fish was a largetooth sawfish (Pristis pristis).
Largetooth sawfish are marine but occasionally enter freshwater
reaches of rivers and are known from the St. Johns (Robins et
al., 1986). If it was a sawfish, then it was odd that Sparke
failed to mention the teeth on the fish’s rostrum. Without
additional information, the honor of the first written report of
a paddlefish cannot be confidently attributed to John Sparke.
French Explorers Encounter the Spatule
Pierre Esprit Radisson was probably the first well-known
European to write about paddlefish. During his Mississippi
voyage of 1655-1658, while exploring Lake Winnebago or
Green Bay, Wisconsin, Radisson saw “fishes . . . some like the
sturgeons [with] a kind of slice at the end of their nose; some
three fingers broad in
the end and two only
near their nose; and
some eight thumbs
long, all marbled of
a blackish color” (Adams, 1961). This record is important,
not merely for priority, but because it confirms that paddlefish
were native to the Great Lakes prior to the construction of
canals in recent times (Rostlund, 1951). It is also interesting
for Radisson’s approximations of rostral dimensions,
which, although imprecise, constitute the first quantitative
morphological data published for the species.
More exciting is the description of a paddlefish by
Father Jacques Marquette, Jesuit missionary and explorer.
His memoirs are readily available, in English and original
French (Thwaites, 1900), and his encounter with a paddlefish
in 1673 is famous and frequently cited (Gowanloch, 1933;
Eifert, 1959; McKinley, 1984). Ignoring local Indian legends
of water demons, Marquette voyaged down the Wisconsin
River and into the Mississippi River where his small boat was
struck by monstrous fishes, one of which is described in some
detail. It was “a very extraordinary kind of a fish. It resembles
Fig. 1.
Coauthor (SGG) with paddlefish collected
from Frasier-Whitehorse Lake, Louisiana.
Upper portion of caudal fin is bent toward
the camera, making the dorsal lobe appear
shorter than it actually is.
the trout, with this difference, that its mouth is larger. Near
its nose [nostril?] which is smaller, as are also the eyes - is a
large bone shaped like a women’s busk, three fingers wide and
a cubit long, at the end of which is a disk as wide as one’s
hand.1This frequently causes it to fall backward when it leaps
out of the water.” The comparison with trout probably alludes
to the lack of large, prominent scales, but the fish described is
undoubtedly a paddlefish. Like Radisson, his description of
the rostrum indicates a substantial expansion near the end, or
a spoon-shaped bill.
In 1758, a military engineer named Antoine Simon La
Page du Pratz listed fishes found in Louisiana and illustrated
three (Gowanloch, 1933). These were the catfish, a gar, and
the paddlefish. “Spatule” was the name given by the French to
the paddlefish and refers to the shovel- or spatula-shaped snout.
La Page du Pratz was probably the first to publish a figure of
a paddlefish, but it is a crude illustration demonstrating either
a lack of firsthand experience with the species (and fish, in
general) or a decidedly odd artistic sensibility. La Page du
Pratz’s account is significant, though, because it represents an
early record of the species from the lower Mississippi Basin.
A more detailed description, and realistic illustrations, were
published shortly afterwards as European scientists attempted
to classify the spatule.
Shark!
Classification of the North American paddlefish was
hampered by its resemblance to sharks and a lack of specimens
with reliable locality data, which, in turn, resulted in a surprising
degree of taxonomic confusion. Although believed to have
been monotypic,2the scientific name of the paddlefish in
North America changed, and multiplied, several times in the
100 years following its formal scientific description.
The first detailed description and illustration of a paddlefish
was by French physician Pierre Jean Etienne Mauduyt de la
Varenne in 1774 (McKinley, 1984). He provided two excellent
line drawings of a specimen (dorsal and ventral views),
morphological description, and measurements of fins and
rostrum. He did not propose any name for the species but
indicated that the fish is “of the class of cartilaginous fishes,
of the genus of sharks,” and that Europeans called it the spatule,
after the pharmacist’s instrument. He also notes that it was
abundant in the Mississippi, but further observes that this
was a fish “of which few naturalists or travelers have perhaps
spoken.” Mauduyt de la Varenne’s account is of special interest
for three reasons: 1) its priority and great detail; 2) the fact
that it was largely overlooked until recently; and 3) the small
size of the specimen (132 mm), which at the time was rare in
museum collections.
The genus of the paddlefish was established 23 years
after Mauduyt de la Varenne’s description, but in the interim
the paddlefish was still regarded as a shark (Jordan, 1917;
McKinley, 1984). J. P. Bonaterre in 1788 re-described the
paddlefish and named it “chien de mer feuille” or “leaf dog of
the ocean,” alluding to its similarity with dogfish sharks.
Bonaterre was apparently working with no available information
on the source of his material or of previous observers; he
noted that the country and habits of the fish were unknown.
He also failed to provide a Latin- or Greek-based binomial
name (genus and species), and was not recognized for the
species description under the modern system of taxonomy,
which was proposed, promoted, and established by Carl
Linnaeus in 1758.
In 1792, Johann Julius Walbaum, who also believed the
fish to be a shark, created a formal binomial as the scientific
name, Squalus spathula. Squalus was, and is, the genus of dogfish
sharks. The species spathula refers to the spatula-like rostrum;
the difference in spelling (spathula vs. spatula) is believed to be
a lapsus calami or error in transcription (N. Douglas, pers.
comm.). In 1797, Bernard Germain Etienne de la Ville-sur-
Illion, Comte de Lacepede (later “Citoyen” La Cepede), realized
that the paddlefish was not a shark, and renamed the fish le
Polyodon feuille, which would later be modified to Polyodon folium
(Bloch and Schneider, 1801). Polyodon means “many teeth”
and probably refers to the numerous and prominent gill-rakers
which resemble teeth (Fig. 2); folium is the Latinized form of
feuille or “leaf ” and refers to the shape of the fish’s paddle.
The name Polyodon folium would persist in scientific literature
for nearly a century (e.g., Mitchill et al., 1827; Wailes, 1854,
Bridge, 1897; Allis, 1903) before the current nomenclature of
Polyodon spathula would be adopted (e.g., Stockard, 1907).
Other names would also be suggested, including Spatularia
reticulata in 1804 and Platirostra edentula in 1817 (Jordan et
al., 1928). Despite the plethora of names, it was always
assumed that there was only a single species of paddlefish,
possibly because prior to the mid-19th century only a few
specimens, most of intermediate size, had been preserved in
American Currents Vol. 26, No. 23
1A busk was a long piece of whalebone used to straighten a woman’s
corset. A cubit was a unit of measure representing the distance from
elbow to tip of the middle finger approximating 18 inches (457 mm), 21
inches (533 mm), or more.
2The Chinese paddlefish, Psephurus gladius, was largely unknown and
not formally described until 1861.
Spring (May) 2000 American Currents 4
museums, and little was known of paddlefish biology or range
(Shaw, 1804; Mitchill et al., 1827).
A Professor’s Plenitude of Paddlefishes
Constantine Samuel Rafinesque, the eccentric naturalist
and professor at the University of Transylvania (Kentucky),
muddled paddlefish classification with his listing of not one,
but four separate species of paddlefish in his classic
Ichthyologia Ohiensis, one of the earliest regional fish books
(Rafinesque, 1820). He recognized and provided descriptions
for Polyodon folium, which he called the western spadefish;
Planirostra edentula, the toothless paddlefish; and Proceros spp.,
the hornfishes. According to Rafinesque, the western spadefish
had a large head, toothed jaws, a long gill flap, a “cuneiform”
rostrum only as long as its head, and was countershaded with
a brown dorsum, and white belly. The toothless paddlefish
had a smaller head, no teeth, a “somewhat cuneiform” rostrum
longer than its head, and the body was uniformly olive-brown.
Polyodon folium and Planirostra edentula are both viewed as
archaic synonyms of Polyodon spathula (Jordan, 1923), but
Rafinesque’s use of the two different binomials may represent
his firsthand knowledge of
two different forms or, at
least, two very different-
looking specimens.
Rafinesque’s reference to paddlefish teeth is open to
interpretation. Adult and sub-adult paddlefish are traditionally
described as toothless (Mitchill et al., 1827; Beach, 1902),
but other sources note that the jaws are “armed with small
teeth” (e.g., Norman, 1948). One taxonomic reference
describes paddlefish teeth in some detail: double rows in the
upper jaw and a single row in the lower jaw of “sharp, curved,
and serrated teeth” (Shaw, 1804). Why the apparent confusion
on such a basic and presumably obvious morphological feature?
Teeth are very prominent in the mouths of newly hatched
(yolk-sac) paddlefish larvae (Ballard and Needham, 1964).
There are double rows of conical teeth in the upper jaw, and
a single row of teeth in the lower jaw, but as paddlefish grow
their teeth become relatively smaller and less apparent (Bemis
et al, 1997). Teeth are still prominent in specimens 50-100
mm total length (TL), but with further growth replacement
becomes less regular and teeth smaller (Grande and Bemis,
1991). Large specimens (> 1500 mm TL) appear toothless,
Fig. 2.
Paddlefish collected from Frasier-
Whitehorse Lake, Louisiana, showing
numerous “toothlike” gill rakers.
the teeth either shed or embedded in the jaw. Pointed ridges
are found in the jaws of some specimens, however, indicating
growth of the jaw bones over the teeth. Rafinesque may have
seen or heard of such specimens. We have observed prominent
serrations in the jaws of fish up to 500 mm TL, which may
represent the “teeth” of this otherwise typically toothless taxon.
The hornfishes were described as “sharks” lacking pectoral
and pelvic fins, with a snout protruding in a straight horn,
belonging to the genus Proceros (Rafinesque, 1820), later
deemed a genus of “mythical” paddlefishes (Jordan, 1923).
According to Rafinesque, Proceros maculatus, the spotted
hornfish, was iron-gray with white spots and lived in the
Mississippi River; P. vittatus had longitudinal stripes and
lived in Lake Ontario (Rafinesque, 1820). The spotted
hornfish is sketched and named in Rafinesque’s infamous
Notebook N. 17, which contained descriptions of fishes not
personally seen by the professor, but reported to him by
other observers (Markle, 1997). Prominent among these
observers was John James Audubon, who reported a series of
fantastic species to Rafinesque, either as a practical joke or to
exact revenge on Rafinesque for the destruction of the
ornithologist’s violin (Barber, 1980; Gilbert, 1981).
Audubon, guilty of fabricating imaginary sturgeons, cannot
be blamed for the hornfishes.
The hornfishes were probably atypical specimens, or
illustrations, of paddlefish. Descriptions could have been based
on mutilated, anomalous, or unusually pigmented specimens.
Morphologically anomalous paddlefish are known (Beard,
1878; Rosen and Hales, 1982; Ramos et al., 1994). Coloration
varies among individuals, and descriptions of individuals with
spots have been published (Mitchill et al., 1827; Alexander,
1914; Coker, 1923). Rafinesque may have appreciated, and
exaggerated, natural variation among individuals more so
than others, but he may also have seen more specimens, or
illustrations of specimens, than had other taxonomists.
If some ichthyologists seemed insufficiently familiar with
paddlefish to appreciate such variation, it was nothing compared
to that of the average American, who rarely had opportunities to
see this species.
Paddlefish and the Public
For many years, curious paddlefish enthusiasts had to be
content viewing rare preserved specimens (or parts of
specimens), published illustrations, and dioramas. Charles
Wilson Peale, in 1784, may have been the first to display a
paddlefish to the general public (McKinley, 1984). Peale’s
paddlefish was the second exhibit acquired for his museum in
Philadelphia that would later become one of the most celebrated
natural history collections in North America (Barber, 1980).
Jerome V. C. Smith describes a severed rostrum from the
collections of the Boston Society of Natural History (Smith,
1833). It was taken from an 18 kg “paddle-nosed sturgeon”
speared in 1830 at LeTart’s Falls on the Ohio River. In 1878,
an artist named David Beard, frustrated “by the absence of
any illustration and the very meager descriptions of our most
curious native specimens,” produced a drawing and detailed
description of a paddlefish, 104 cm TL, collected at St.
Louis, Missouri (Beard, 1878). Beard’s drawing shows a
paddlefish with its rostrum angled down towards the river
bottom. The left side of the specimen is depicted, possibly for
reasons of zoological protocol, but more likely because the
right opercular flap of this specimen was abnormally short.
In 1910, an American Museum of Natural History
expedition conducted by Louis Hussakof collected paddlefish
from Moon Lake, Mississippi (Dean, 1923). Paddlefish
replicas were cast from molds made in the field and a diorama
was later constructed at the museum showing a group of
paddlefish entering the seine of a fisherman. A photograph of
the exhibit in Natural History magazine suggests that the
diorama was impressive. Hussakof, though, did not refer to
paddlefish in very impressive terms. At the 40th annual meeting
of the American Fisheries Society later that year, in a talk
“illustrated with lantern slides,” he described paddlefish as
feeble, clumsy, and having “absolutely no sport value”
(Hussakof, 1910). His conclusions, however, were based on
their behavior in the giant winch-operated seines deployed by
commercial fishermen from specially designed boats. Large
commercial operations had developed, just a decade or so
earlier, on the Ohio and Mississippi Rivers to catch paddlefish
for their meat, caviar, and oil. Mechanized and highly efficient
fishing operations would soon deplete many of these formerly
abundant populations (Alexander, 1914; Alexander, 1915).
Repeated attempts by fishery scientists and public
aquaria to maintain healthy paddlefish were apparently not
successful for many years, the result being that the general
public rarely, if ever, saw live paddlefish. Adult and sub-adult
fish could be safely transferred to in-lake enclosures for short
periods (Alexander, 1915), but most paddlefish transported
by specially equipped boat or by rail car rarely survived
extended journeys (Coker, 1923). Small specimens were
maintained for several years in a small, 5 m deep reservoir in
Fairport, Iowa, but lost equilibrium when moved to tanks
(Coker, 1923). One paddlefish was maintained at the
American Currents Vol. 26, No. 25
Spring (May) 2000 American Currents 6
Lincoln Park Aquarium for nearly a year, but was fed only
sporadically and apparently with limited success; it was in
“good, though not fat, condition until the accident which
caused its death” (Weed, 1925). The New York Aquarium,
after a quarter-century of operation, listed the paddlefish in
its tour guide but showed no picture and indicated that it “is
not adapted to life in captivity,” with specimens living but a
few days (Townsend, 1929). Years later, the director of the
Shedd Aquarium noted that the easily injured rostrum and the
difficulty of supplying zooplankton as food made the paddlefish
difficult to keep (Chute, 1947). Even today, long-term captivity
of paddlefish presents special challenges to aquarium personnel.
It is not uncommon to see fish on display at public aquaria
that are conspicuously skinnier and more blunt-nosed than
their cousins in the wild.
Search for the Smallest Spoonbill
If adult paddlefish were rare curiosities for the general
public, young paddlefish were unobtainable “holy grails” for
certain biologists. By the beginning of the 20th century, most
of the specimens described in print or preserved in museum
collections were adults or subadults 500-1500 mm long.
Specimens 100-200 mm were unusual, and specimens less
than 100 mm were virtually unknown. There was intense
scientific interest in finding very small paddlefish so that
early anatomical development (e.g., jaw teeth) and life history
could be studied, and so that spawning and nursery grounds
could be identified.
In 1910, following Hussakof ’s paddlefish talk, Barton
Warren Evermann commented that the “queerest thing about
the spoonbill is this, that no one has been able to locate the
spawning grounds and to find young fry” (Hussakof, 1910).
The following year, three papers were published announcing
independent discoveries of young-of-year paddlefish. One 74
mm specimen was collected in 1910 from the Mississippi
River near St. Louis (Danforth, 1911). It was believed to be
the smallest specimen recorded. Famed naturalist Thomas
Barbour read the account and reported that there existed in
Harvard’s Museum of Comparative Zoology additional juvenile
specimens, three of which were even smaller: 35-65 mm in
length (Barbour, 1911). One was collected in Arkansas, the
others near St. Louis, prior to 1860! The specimens were
originally in the personal collection of Louis Agassiz and
most were well-preserved. Both articles were well-illustrated,
but neither described the method of capture or the habitats in
which the baby paddlefish were found.
Details on sampling young-of-year, albeit slightly larger,
paddlefish were provided by dedicated collector William F.
Allen (Allen, 1911). Allen was employed by Edwards Phelps
Allis, Jr., an anatomist specializing in primitive fishes, and was
commissioned to collect all “ganoids” possible. Before deciding
on where to collect, Allen reviewed all available information
and selected the confluence of the Ohio and Mississippi
Rivers as his sampling site. For one year he seined and set
hoop-nets in all habitats and was rewarded with 25 specimens
of paddlefish 100-150 mm. All of these, however, were collected
on a single date, 1 July 1904, from a tributary slough during
a drop in river stage, when water was rapidly receding from
the slough. Fish had not been collected there previously, and
Allen believed that they migrated during high water the night
before or early that same morning. Allen hurriedly preserved
the paddlefish (collected during a “violent thunderstorm”),
but noted that the bodies of the live paddlefish were almost
transparent. He did not observe young paddlefish again until
late August and early September, when he seined mud bars
and sandbars of the Ohio River at night and early morning.
Earlier that century, a reward of $5 offered for a paddlefish
less than 150 mm in length went unclaimed (Beach, 1902). In
the 1920s, anatomist Allis, wanting even smaller paddlefish,
offered a $1000 reward for any specimen of paddlefish less
than 50 mm, a reward that was not claimed and eventually
withdrawn (Gilbert, 1981). Smaller specimens of paddlefish
would later be discovered, however.
On the morning of 14 May 1932, David Thompson was
seining the head of a large island in the Mississippi River
near Grand Tower, Illinois, and collected seven specimens of
17-20 mm postlarval paddlefish (Thompson, 1933). These
were collected with a 6 m, 4 mm-mesh seine. Collected along
with the paddlefish were river prawns (Macrobrachium sp.),
minnows, sunfishes, and dragonfly nymphs. Comparably
sized specimens were again collected by Thompson on 29
May 1944, when he seined the main channel of the
Mississippi River at an island sand bar near Cape Girardeau,
Missouri (Larimore, 1949). There, water was less than one
meter deep, turbid, and 25°C. River stage was high, and
substrate was sand with an overlaying layer of muddy ooze.
Thompson was again using a 4 mm-mesh seine.
The development of paddlefish is now well documented
(Yeager and Wallus, 1990; Bemis and Grande, 1992). But at
the time of their collection, Thompson’s specimens were
considered sensational because they showed how some
structures, notably the rostrum, changed in size and shape
with the growth of the paddlefish.
How Does a Rostrum Grow?
Anecdotal comments indicated that the rostrum did not
grow at the same rate as the rest of the paddlefish (e.g.,
Brehm, 1893). Charles Stockard, who conducted one of the
earliest field studies of paddlefish in 1905, provided the first
quantitative data to support this hypothesis (Stockard, 1907).
Later, David Thompson would use those and other data from
preserved paddlefish to describe how the rostrum grows
(Thompson, 1933). When paddlefish fry hatch from their egg,
the rostrum is very small. It grows rapidly—more rapidly, in fact,
than the body (growth of a body part that is disproportionately
faster than the growth of the body of an animal is called positive
allometric growth). This continues until the paddlefish is
approximately 80 mm eye-to-fork length (EFL). Then rostrum
growth slows down and keeps pace with growth of the fish
(isometric growth). When the fish is larger than 250 mm,
rostrum growth becomes slower than that of the fish’s body
(negative allometric growth).
In subadult and adult paddlefish, the rostrum is
absolutely longer in larger fish, but is relatively shorter when
expressed as a percentage of body size. How this affects the
biology of paddlefish is not known. At one time, the rostrum
was believed to be an implement used by the paddlefish to
acquire food, either by digging and stirring aquatic invertebrates
into the water column or
by manipulating aquatic
plants for grazing
(Mitchill et al., 1827;
Beard, 1878; Beach,
1902). The rostrum-as-
utensil hypothesis persisted for decades (Norman, 1948).
Doubts were raised nearly a century ago, however, and the
theory is given little credibility today (Stockard, 1907;
Grande and Bemis, 1991). The rostrum is now believed to
function primarily as an electro-sensory organ (Bemis et al.,
1997), but it can be injured or lost in turbulent water upon
impact with underwater structure (Coker, 1923).
Observations of healthy paddlefish that are missing rostra
suggest that individuals with shorter (or absent) rostra may
function similarly to those with larger, well-developed rostra
(Stockard, 1907; Gannon and Howmiller, 1973).
Another, Undescribed Paddlefish in North America?
Rafinesque’s penchant for describing new species and
the pronounced allometric growth of the rostrum may have
obscured the existence of multiple forms of paddlefish.
Natural history illustrations made during the 19th century
(Fig. 3), and two common names for the fish used almost
American Currents Vol. 26, No. 27
Fig. 3.
Illustrations of paddlefish from
natural history references:
A) Bloch and Schneider, 1801;
B) Wood, 1863; C) Brehm and
Hacke, 1892; D) Cuvier, 1833-1837,
reproduced in Aramata, 1990.
Spring (May) 2000 American Currents 8
interchangeably, suggest two distinctive morphotypes based
on rostral shape. “Paddlefish” implies a long, narrow,
straight-sided snout; “spoonbill” suggests a shorter, broader,
terminally expanded snout. Additionally, some ichthyologists
have made tantalizing references to a second form of paddlefish
in North America. George Sprague Myers believed that there
were two species of North American paddlefishes, “one not
yet described,” but unfortunately did not provide a basis for
his rationale (Myers, 1949). It is probable that Myers was
influenced by an observation Stockard made while doing his
fieldwork in the lower Mississippi basin. Stockard believed
that there were two distinguishable forms of paddlefish in the
population he was studying: a long, narrow-nosed form in the
rivers, and a short, broad-nosed form in oxbow lakes
(Stockard, 1907). Unfortunately, Stockard published data
supporting his observations on negative allometric growth of
the paddlefish rostrum but did not provide supporting data
for the existence of multiple rostral forms.
While doing stream surveys in the Mississippi delta, we
also observed substantial variation in the shapes of paddlefish
rostra. Was Stockard correct? To determine the existence of
two or more rostral forms, we would need a large number of
specimens. In 1993, we were working in the Big Sunflower
River in Mississippi and met commercial fisherman William
Lancaster, who frequently encountered paddlefish as bycatch
when fishing for catfish, buffalo,
and gar. He agreed to save
dead and dying paddlefish for
us during his daily net-checks
along a reach of the river that was contiguous with five oxbow
lakes. The Mississippi Department of Wildlife, Fisheries,
and Parks modified our scientific collecting permit accordingly,
and between 1 March 1994 and 28 February 1995, we
obtained 118 specimens that were 411 to 1009 mm EFL.
On these specimens, we measured length of the rostrum,
breadth at 10 equidistant points along its length, and certain
distances between facial features (Fig. 4). Measurements
were used to calculate indices that described rostral size and
shape: relative length of the rostrum (rostrum length/paddlefish
EFL) and anterior expansion of the rostrum or just how
spoonlike it was shaped (maximum rostrum breadth/minimum
rostrum breadth).
We observed, like others had earlier, that relative rostrum
length decreased as size of adult paddlefish increased.
Because all of our specimens were from a single location, though,
we were able to develop a population-specific relationship
between paddlefish and rostrum size and to evaluate variation
that occurred within a single population. We found that relative
rostrum length (as % EFL) could be estimated from paddlefish
size (EFL in millimeters), or vice versa, using this relationship:
Fig. 4.
Rostral and facial metrics
used to describe variation
in rostrum size and shape.
Width of Rostrum
Facial Metrics
1 Operculum - Spiracle
2 Spiracle - Eye
3 Spiracle - Nostril
4 Eye - Nostril
Width of Head
Rostrum Length
Relative Length of Rostrum =
0.716 - (3.61) (10-4) (Length of Paddlefish)
Paddlefish size, however, only explained 49% of the variation
in rostrum length. Statistically, the relationship is “significant,”
but there is still a substantial amount of variation among
individuals that is independent of size. For example, fish that
are approximately 600 mm EFL have a predicted rostrum
length of 50% EFL, but some of our fish this size had rostra
that were considerably shorter (37% EFL) and somewhat
longer (57% EFL).
Could our short-nosed specimens be Stockard’s oxbow-
dwelling spoonbill, and long-nosed specimens his riverine
paddlefish? There was an easy way to test this: a simple x-y
plot of relative rostrum length and rostral expansion (Hoover
et al., 2000). If we had Stockard’s two morphotypes, then the
points would cluster out as long-, straight-nosed forms, and
short-, broad-nosed forms. To minimize effects of allometric
growth, we selected 30 specimens from a narrow size range
(600-650 mm) and plotted anterior expansion of the rostrum
against the relative rostrum length. Our results did not indicate
two cleanly discrete forms, however. There was one large
cloud of points in which the majority of fish had rostra greater
than 42% EFL with rostral expansion less than 165% its
minimum width. One fish looked a little different, though. It
had a rostrum that was 38% EFL and was expanded 175% its
minimum width. We concluded that if there was a short-, broad-
nosed form, then it was substantially less common and not
strikingly different from the more common longer, straighter-
nosed paddlefish. Unlike the daring Professor Rafinesque, we
were not yet ready to describe a new form of spoonbill.
Acknowledgments
Our paddlefish research was funded by the U.S. Army
Corps of Engineers Vicksburg District. The following
individuals provided historical information or insights into
paddlefish biology: Brooks Burr, Bil Gilbert, William
Lancaster, Doug Markle, Frank Rupert, Lindsey Williams.
Arcane paddlefish literature was obtained for us by James
Dolan and Kathleen Wilson. Manuscript review was provided
by Neil Douglas. The Chief of Engineers granted permission
to publish this document. Many thanks to all of the above.
Literature Cited [and Annotations]
Adams, A. T. (Ed.). 1961. The explorations of Pierre Esprit Radisson: from the
original manuscript in the Bodleian Library and the British Museum. Ross
and Haines, Inc., Minneapolis, 258 pp. + lxxxiv.
Alexander, M. L. 1914. The paddle-fish (Polyodon spathula). (Commonly
called “spoonbill cat.”) Trans. Am. Fish. Soc. 44: 73-78. [Article provides
early documentation of a disappearing population in an intensively fished
lake and advocates protective measures for paddlefish.]
Alexander, M. L. 1915. More about the paddle-fish (Polyodon spathula).
Trans. Am. Fish. Soc. 45: 34-39. [Article describes successful confinement
of paddlefish in enclosures and includes notes on the structure of the
digestive system.]
Allen, W. F. 1911. Notes on the breeding season and young of Polyodon
spathula. Journal of the Washington Academy of Science 1: 280-282.
Allis, E. P., Jr. 1903. On certain features of the lateral canals and cranial
bones of Polyodon folium. Zoologische Jahrbucher 17: 659-679.
Aramata, H. 1990. Fish of the world: a collection of 19th century paintings.
Portland House, New York, 279 pp.
Ballard, W. W. and R. G. Needham. 1964. Normal embryonic stages of
Polyodon spathula (Walbaum). Journal of Morphology 114: 465-478.
Barber, L. 1980. The heyday of natural history. Doubleday and Company,
Garden City, New York, 320 pp. [Book notes Peale’s acquisition of a
paddlefish and describes in detail the incident involving Rafinesque’s
destruction of Audubon’s violin.]
Barbour, T. 1911. The smallest Polyodon. Biol. Bull. 21: 207-215.
Beach, H., Sr. 1902. The paddle fish (Polyodon spathula). Bulletin of the
Wisconsin Natural History Society. [A fascinating article that speculates
freely, and incorrectly, about the feeding and hibernation of paddlefish.]
Beard, D. C. 1878. The paddle fish of the Mississippi. Scientific American
39: 391.
Bemis, W. E. and L. Grande. 1992. Early development of the actinopterygian
head. I. External development and staging of the paddlefish, Polyodon
spathula. Journal of Morphology 213: 47-83. [Detailed electron microscope
photographs and drawings of paddlefish head at more than 20 stages of
development.]
Bemis, W. E., E. K. Findeis, and L. Grande. 1997. An overview of
Acipenseriformes. Env. Biol. Fishes 48: 25-71.
Berrill, N. J. 1952. Journey into Wonder. Dood, Mead and Company, New
York, 338 pp.
Bloch, M. E. and J. G. Schneider. 1801. Systema ichthyolgiae. Reprint 1967.
Verlag Von J. Cramer, Lehre.
Brehm, A. E. and W. Hacke. 1892. Die fische. Brehm’s Tierleben,
Bibliohraphisches Institut, Leipzig, Germany.
Bridge, T. W. 1897. On the presence of ribs in Polyodon (Spatularia) folium.
Proceedings of the Zoological Society of London XX: 722-724.
Burr, B. M. 1981. Polyodon spathula (Walbaum). Paddlefish. Pp. 45-46 in
D. S. Lee, et al. Atlas of North American Freshwater Fishes, North Carolina
State Museum of Natural History, Raleigh, i-x + 854 pp.
Carlander, H. B. 1954. A history of fish and fishing in the upper Mississippi
River. Upper Mississippi River Conservation Committee, Springfield,
Il., 96 pp. [This well-researched synopsis covers many species of fishes
and bivalves including paddlefish encounters by La Salle in 1682, Captain
Jonathan Carver in 1767, and Prince Maximilien of Wied in 1843.]
Carlson, D. M. and P. S. Bonislawsky. 1981. The paddlefish (Polyodon
spathula) fisheries of the midwestern United States. Fisheries 6: 17-27.
Chute, W. H. 1947. Guide to the John G. Shedd Aquarium. Shedd Aquarium,
Chicago, 236 pp.
Clayton, L. A., J. V. Knight, Jr., and E. C. Moore (Eds.). 1996. The De Soto
chronicles: the expedition of Hernando De Soto to North America in 1539-
1543. University of Alabama Press, Tuscaloosa, Al.
Coker, R. E. 1923. Methuselah of the Mississippi. Scientific Monthly 16: 89-
103. [Good summary of paddlefish biology.]
Danforth, C. H. 1911. A 74 mm Polyodon. Biol. Bull. 20: 201-204.
American Currents Vol. 26, No. 29
Spring (May) 2000 American Currents 10
Dean, B. 1923. The Department of Fishes, American Museum. Natural
History 23 (6): 606-616.
Dillard, J. G., L. K.Graham, and T. R. Russell. 1986. The paddlefish: status,
management, and propagation. North Central Division, American Fisheries
Society. Special Publication No. 7. Columbia, Mo., 159 pp.
Eifert, V. S. 1959. River world: wildlife of the Mississippi. Dodd, Mead, and
Company, New York, 271 pp.
Gannon, J. E. and R. P. Howmiller. 1973. Ecological notes on paddlefish
(Polyodon spathula) with short rostrums. Michigan Academician 6: 217-222.
Gilbert, B. 1981. End of a long journey for spoonbill cat. Audubon 83: 66-71.
Gowanloch, J. N. 1933. Fishes and fishing in Louisiana. Bulletin No. 23,
Louisiana Department of Conservation, New Orleans, La., 638 pp.
Grande, L. and W. E. Bemis. 1991. Osteology and phylogenetic relationships
of fossils and recent paddlefishes (Polyodontidae) with comments on the
interrelationships of Acipenseriformes. Journal of Vertebrate Paleontology
Vol. 11, Supplement to No. 1: 1-121.
Hakluyt, R. 1810. The voyage made by M. Iohn Hawkins Esquire, and afterward
knight, Captain of the Iesus of Lubek, one of her Maiesties shippes, and General
of the Salomon, and other two barkes going in his company, to the coast of
Guinea, and the Indes of Noua Hispania, begun in An. Dom. 1564. Collection
of the Early Voyages, Travels, and Discoveries of the English Nation Vol.
III: pp. 594-618. Evans, Mackinlay, and Priestely, London. [Sparke’s
written observations of fishes are frustratingly brief for native fish
enthusiasts with one exception: a detailed account of the behavior and
interactions between flying fishes and bonitos.]
Hoover, J. J., S. G. George, and K. J.Killgore. 2000. Rostrum size of
paddlefish (Polyodon spathula) (Acipenseriformes: Polyodontidae) from
the Mississippi delta. Copeia 2000: 288-290.
Hussakof, L. 1910. The spoonbill fishery of the lower Mississippi. Trans.
Am. Fish. Soc. 40: 245-248. [Plate depicts special boat designed for seining
adult paddlefish and a typical catch being processed for roe.]
Jordan, D. S. 1917. The genera of fishes. Rpt. 1963. Stanford University
Press, Stanford, 576 pp.
Jordan, D. S. 1923. A classification of fishes. Rpt. 1963. Stanford University
Press, Stanford, 243 pp.
Jordan, D. S., B. W. Evermann, and H. W. Clark. 1928. Checklist of the fishes
and fishlike vertebrates of North and Middle America north of the northern
boundary of Venezuela and Colombia. Rpt. 1930. U.S. Government Printing
Office, Washington, D.C., 670 pp.
Larimore, R. W. 1949. Changes in the cranial nerves of the paddlefish,
Polyodon spathula, accompanying development of the rostrum. Copeia
1949: 204-212.
Markle, D. F. 1997. Audubon’s hoax: Ohio River fishes described by
Rafinesque. Archives of Natural History 24: 439-447. [A fascinating
analysis of one of the most celebrated stories in ichthyology.]
McKinley, D. 1984. History of a neglected account of the paddlefish,
Polyodon spathula. Copeia 1984: 201-204.
Meurger, M. and C. Gagnon. 1988. Lake monster traditions: a cross-cultural
analysis. Fortean Tomes, London, 320 pp. [Book combines anthropology,
folklore, popular culture, and biology to examine accounts of lake and
river monsters; of particular interest to native fish enthusiasts are the roles
attributed to eels, gars, pikes, and sturgeons in cryptozoology.]
Mitchill, S. L., S. P. Hildreth, and J. W. Clemens. 1827. Notice of the
spoonbill sturgeon or paddle fish, of the Ohio, (Polyodon feuille of
Lacepede). American Journal of Science and Arts 12: 201-205. [Three letters
describing and illustrating paddlefish.]
Myers, G. S. 1949. Salt-tolerance of fresh-water fish groups in relation to
zoogeographical problems. Bigdragen tot de Dierkunde 28: 315-322.
Norman, J. R. 1948. A history of fishes. A. A. Wyn, Inc., New York, 463 pp.
Rafinesque, C. S. 1820. Ichthyologia Ohiensis, or natural history of the fishes
inhabiting the Ohio River and its tributary streams preceded by a physical
description of the Ohio and its branches. Rpt. 1970. Arno Press, 90 pp.
Ramos, K. T., C. S. Berkhouse, and J. N. Fries. 1994. Apparent sunburn of
juvenile paddlefish. Prog. Fish.-Cult. 56: 214-216. [Article demonstrates
how sunburn can cause rostral deformities in paddlefish.]
Robins, C. R., G. C. Ray, and J. Douglass. 1986. A field guide to the Atlantic
Coast fishes. Peterson Field Guide Series. Houghton Mifflin Company,
Boston, 354 pp.
Rosen, R. A. and D. C. Hales. 1982. Occurrence of a blind paddlefish,
Polyodon spathula. Copeia 1982: 212-214. [Blind paddlefish was also
melanistic.]
Rostlund, E. 1951. Three early historical reports of North American
freshwater fishes. Copeia 1951: 295-296.
Shaw, G. 1804. Spatularia spatularia. Pp. 362-364. In: General zoology, or
systematic natural history. Vol. V. G. Kearsley, London.
Smith, J. V. C. 1833. Natural history of the fishes of Massachusetts, embracing a
practical essay on angling. Rpt. 1970. Freshet Press, New York, 400 pp.
Stockard, C. R. 1907. Observations on the natural history of Polyodon
spathula. American Naturalist 41: 753-766.
Thompson, D. H. 1933. The finding of very young Polyodon. Copeia 1933:
31-33.
Thwaites, R. G. (Ed.) 1900. Voyages of Marquette by Jacques Marquette.
Vol. LIX. In: The Jesuit relations and allied documents: travels and explorations
of the Jesuit missionaries in New France 1610-1791. The Burrows Brothers
Company, Cleveland. [1966 reprint available through University
Microfilms, Ann Arbor.]
Townsend, C. H. 1929. Guide to the New York Aquarium. New York
Zoological Society, New York, 170 pp.
Wailes, B. L. C. 1854. Report on the agriculture and geology of Mississippi
embracing a sketch of the social and natural history of the state. E. Barksdale,
State Printer, Jackson, Ms., 371 pp.
Weed, A. C. 1925. Feeding the paddlefish. Copeia 146: 67-68.
Williams, L. W. 1986. Boldly onward. Precision Publishing, Charlotte
Harbor, Fl., 192 pp.
Wood, J. G. 1863. The illustrated natural history. Routledge and Sons, London.
Yeager, B. L. and R. Wallus. 1990. Polyodontidae. Pp. 47-56. In: R. Wallus,
T. P. Simon, and B. L. Yeager. Reproductive biology and early life history of
fishes in the Ohio River drainage. Vol. I. Acipenseridae through Esocidae.
Tennessee Valley Authority, Chattanooga, Tn. [Good drawings and
detailed survey of literature on reproduction and development.]
“It’s not how long it is. It’s how you use it!”
© Todd Daniels