The following species increased in abundance from 1957 to 1959 (Tables
10 and 11): long-nosed gar, short-nosed gar, river carpsucker, creek
chub, gravel chub, sucker-mouthed minnow, mountain minnow, blunt-nosed
minnow, parrot minnow, stoneroller, stonecat, Neosho madtom, green
sunfish, slender-headed darter, and orange-throated darter.
These species can be separated into three groups, characteristic of
different habitats but having in common a preference for permanent flow.
One group, composed of long-nosed gar, short-nosed gar, river
carpsucker, gravel chub, mountain minnow, parrot minnow, and Neosho
madtom, prefers streams of moderate to large size.
A second group composed of creek chub, sucker-mouthed minnow,
stoneroller, and orange-throated darter occurs most abundantly in small,
permanent streams. The green sunfish may be included here on the basis
of its abundance at the upper Neosho station; however, this is a pioneer
species and does not require permanent flow.
The third group is characteristic of continuously flowing water, but in
both upstream and downstream situations. The species in this group
(blunt-nosed minnow, stonecat, and slender-headed darter), increased in
response to a resumption of permanent flow, but did not respond as
quickly as did channel catfish, flatheads and freshwater drum, which are
discussed subsequently.
The fact that riffle-insects were abundant throughout my study convinces
me that food was not a limiting factor in the re-establishment of the
fish-fauna on riffles of the Neosho River.
The following species decreased in abundance during my study (Tables 10
and 11): gizzard shad, carp, rosy-faced shiner, blunt-faced shiner, red
shiner, mimic shiner, black bullhead, yellow bullhead, channel catfish,
flathead, slender madtom, tadpole madtom, freckled madtom, spotted bass,
largemouth, black crappie, fan-tailed darter, and freshwater drum.
Among the species that decreased, three groups, characteristic of
different habitats, can be distinguished. The first group occurs most
commonly in ponded conditions or in slowly flowing streams. Species in
this group are: shad, carp, black bullhead, tadpole madtom, largemouth,
black crappie, and white crappie. Bullhead, bass and crappie commonly
occur in farm ponds and lakes in Kansas and seem less well adapted to
streams. It is therefore not surprising to find that these species
decreased in abundance when flow was resumed.
A second group, composed of rosy-faced shiner, blunt-faced shiner, mimic
shiner, slender madtom, freckled madtom, spotted bass, and fan-tailed
darter, normally is characteristic of clear tributaries rather than the
mainstream of rivers. These species probably used the mainstream as a
refugium during drought; with the resumption of flow, conditions became
unsuitable for these populations in the mainstream. At the same time,
conditions probably became favorable to the re-establishment of these
species in tributaries. Metcalf (1959:396) listed the rosy-faced shiner,
blunt-faced shiner and mimic shiner as species that were characteristic
of upland tributaries in the Flint Hills and Chautauqua Hills of
Chautauqua, Cowley and Elk counties in Kansas. The slender madtom and
fan-tailed darter are more common in clear streams of southeast Kansas
than in other areas of the state (Cross, personal communication and data
of the State Biological Survey of Kansas). Both species are recorded by
Hall (1952:57-58) only in upland tributaries on the east side of Grand
(Neosho) River in the Fort Gibson Reservoir area of Oklahoma. Neither
species was taken in faunal studies of the Verdigris River in Oklahoma
(Wallen, 1958), in the Verdigris and Fall rivers in Kansas (Schelske,
1957), or by Metcalf (1959).
The spotted bass is not so restricted in its distribution and its
habitat-requirements as are other species in this group; but, in Kansas,
spotted bass are most abundant in clear creeks in the southeast part of
the state.
The freckled madtom was taken in most of the studies cited above and is
most common in the smaller streams of the southeast one-fourth of Kansas
and the northeast one-fourth of Oklahoma. Schelske (1957:47) reports
that the freckled madtom was taken only in March, April, October and
November in the Verdigris River, Kansas. My only record of this species
was obtained in the Neosho River in April, 1958.
The third group is composed of channel catfish, flathead, and freshwater
drum. This group represents that element of the population that
responded most quickly to the resumption of continuous flow. The fact
that adult channel catfish and flatheads live in pools and do not
require flowing water to spawn gives these species a survival advantage
as well as a reproductive advantage over obligatory riffle fishes (such
as most darters) in the highly variable conditions found in Kansas
streams. These factors resulted in unusually high reproductive success
in 1957. Subsequent survival of fry was excellent; however, some
mortality in the highly-dominant 1957 year-class became apparent in the
1958 and 1959 collections, accounting for a numerical decline in these
species. The ability to respond immediately to increased flow is an
adaptive feature that allows these species to maintain high levels of
abundance in the highly fluctuating streams of Kansas.
The continuous flow that occurred in 1957 in the Neosho and Marais des
Cygnes rivers, for the first time in four years, provided the necessary
habitat for survival of young catfish hatched in that year. The nearly
complete absence of other species on the riffles, and the abundant
populations of riffle-insects that I observed in the summer of 1957,
were undoubtedly factors contributing to the survival of young.
The decrease in abundance of the red shiner may be partially due to an
increase in the numbers of other species that are well adapted to
conditions of permanent flow. At the completion of my study, the red
shiner was still the most abundant minnow in both rivers. In 1957 this
species was common in many habitats, including swift riffles, that were
later occupied by madtoms, darters, the gravel chub, mountain minnow and
sucker-mouthed minnow.
The basic pattern of change was clearly an increase in the species that
are characteristic of permanently flowing waters, and a decrease in the
species that are characteristic of ponds or small, clear streams.