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Despite decades of commercial harvest of bigmouth buffalo (Ictiobus cyprinellus) from Jamestown Reservoir, North Dakota, and the recent rapid growth of sport bowfishing that targets this species, there is a lack of biological information on this native catostomid. At present, no-limit recreational and commercial harvest of bigmouth buffalo occurs in North Dakota, with no harvest-reporting for recreational take. A long-lived life history was recently documented for this species, with a life-span exceeding 100 years. At Jamestown Reservoir, bigmouth buffalo were aged to 58 years of age, with onset of sexual maturity 10 years for females. Evidence for episodic recruitment over a 60-year period was in 1962–1979, 1993–2011, and 2017, with recruitment success more likely during non-drought periods. Annual commercial harvest data from this reservoir indicate bigmouth buffalo have declined significantly over the past 30 years, most precipitously since 2010 during the bowfishing era. The demographic patterns, episodic recruitment, and harvest changes observed in this population are relevant for informing management of bigmouth buffalo and other long-lived freshwater fishes.

Although the pace of senescence varies considerably, the physiological systems that contribute to different patterns of senescence are not well understood, especially in long-lived vertebrates. Long-lived bony fish (i.e., Class Osteichthyes) are a particularly useful model for studies of senescence because they can readily be aged and exhibit some of the longest lifespans among vertebrates. In this study we examined the potential relationship between age and multiple physiological systems including: stress levels, immune function, and telomere length in individuals ranging in age from 2 to 99 years old in bigmouth buffalo (Ictiobus cyprinellus), the oldest known freshwater teleost fish. Contrary to expectation, we did not find any evidence for age-related declines in these physiological systems. Instead, older fish appeared to be less stressed and had greater immunity than younger fish, suggesting age-related improvements rather than declines in these systems. There was no significant effect of age on telomeres, but individuals that may be more stressed had shorter telomeres. Taken together, these findings suggest that bigmouth buffalo exhibit negligible senescence in multiple physiological systems despite living for nearly a century.

The River Niger is blessed with diverse fish species and aquatic life. The study of the fish fauna and biodiversity along the River Niger was conducted from October 2016 to December 2018. A total of 35 species belonging to 18 families were obtained from this study. New to this River as regards literature are the family Solidae and Catostomidae. The sole fish (Solea solea) (0.16%) with only 1 representation while the Catastomids were represented by 3 species; Ictiobus niger (1.73%), Ictiobus cyprinellus (2.20%), Ictiobus bubalus (2.52%). Other species obtained were the Mormyrus rume 3.93%, Polyterus bichir (2.99%) and Protopterus annectens (7.08%). The most abundant of species observed was Gymnarchus niloticus (8.49%) of the family Gymnarchidae while the least was Solea solea (0.16%). The biodiversity indices revealed that Station 2 had the most evenly distributed species and the most of diverse species though Station 1 had the most number of species. Station 3 however had the least of species obtained. It is concluded the River Niger is still productive and in good condition, capable of maintaining and managing fish species according to condition factor.

Mortality of fish early life stages was measured in a pressure vessel to simulate vertical displacement within the water column. Mortality was measured for three pressure regimes for four fish species: larval bigmouth buffalo Ictiobus cyprinellus, larval blue catfish Ictalurus furcatus, juvenile bluegill Lepomis macrochirus, and juvenile largemouth bass Micropterus salmoides. The maximum pressure‐change tested, 344.8 kPa, equivalent to a 35.2 m displacement of fish within the water column, did not cause significant mortality of larvae or juveniles. Since 32.5 m exceeds depths in most inland navigation channels and possibly the depth to which rapid propeller induced water mixing occurs, the range of pressure changes that could be experienced by early life stages during towboat mixing of the water column will not result in significant mortality.

Understanding the age structure and population dynamics of harvested species is crucial for sustainability, especially in fisheries. The Bigmouth Buffalo (Ictiobus cyprinellus) is a fish endemic to the Mississippi and Hudson Bay drainages. A valued food-fish for centuries, they are now a prized sportfish as night bowfishing has become a million-dollar industry in the past decade. All harvest is virtually unregulated and unstudied, and Bigmouth Buffalo are declining while little is known about their biology. Using thin-sectioned otoliths and bomb-radiocarbon dating, we find Bigmouth Buffalo can reach 112 years of age, more than quadrupling previous longevity estimates, making this the oldest known freshwater teleost (~12,000 species). We document numerous populations that are comprised largely (85–90%) of individuals over 80 years old, suggesting long-term recruitment failure since dam construction in the 1930s. Our findings indicate Bigmouth Buffalo require urgent attention, while other understudied fishes may be threatened by similar ecological neglect.

Species invasions may disrupt resource partitioning in aquatic ecosystems, potentially resulting in competitive exclusion, or shifts in resource use by native species. Diet overlap between invasive Silver Carp (Hypophthalmichthys molitrix) and native planktivores has been linked to declines in condition and abundance of native planktivores. However, there is little information on how such diet overlap varies temporally. We used stable-isotope ratios to examine seasonal resource overlap among Silver Carp and two native planktivores, Gizzard Shad (Dorosoma cepedianum) and Bigmouth Buffalo (Ictiobus cyprinellus). Resource overlap between Bigmouth Buffalo and Silver Carp was minimal (

Planktivorous Silver Carp Hypophthalmichthys molitrix and Bighead Carp H. nobilis have successfully invaded much of the Upper Mississippi River System and its tributaries during the last 30 years. During the initial years of the invasion, concurrent declines in the body condition and the catch per unit effort (CPUE) of planktivorous Gizzard Shad Dorosoma cepedianum and Bigmouth Buffalo Ictiobus cyprinellus were attributed to competition with Asian carp. Using an additional seven years of data (2007–2013), we assessed whether Silver Carp have continued to exert adverse pressure on the condition, CPUE, and biomass of native planktivores or whether there is evidence of a potential rebound in the populations of native planktivores. The extended data set reaffirms the body condition and the CPUE of Bigmouth Buffalo remain significantly reduced. However, unlike previous analyses, we also observed significant reductions in the CPUE of Gizzard Shad. Additionally, new results show that the CPUE and biomass of Bigmouth Buffalo were more inversely related to Silver Carp CPUE and biomass relative to the CPUE and biomass of Gizzard Shad. These results reinforce that Silver Carp likely suppress native planktivores and also suggest that diet and other life-history traits may explain some of the subtle differences in species-specific responses. Our results also emphasize that long-term data can be critical to understanding how non-native species can influence native fish population dynamics and how this influence may change over time.

Silver carp (Hypophthalmichthys molitrix) are a potential threat to native filter feeders and larval fish due to dietary overlap. To test for dietary overlap and selectivity, we collected diet samples from invasive silver carp and two native filter feeders (gizzard shad Dorosoma cepedianum and bigmouth buffalo Ictiobus cyprinellus), and river plankton samples at three sites on the Wabash River during the spring and summer of 2015. Contents of diet items were identified to major group and quantified. Diet proportions were compared among seasons, sites and species. Diet selectivity was calculated using the Manly–Chesson diet selectivity index. The results of our diet analysis showed that silver carp had significantly dissimilar diets among seasons and displayed dietary overlap with native fishes. We did not find a significant difference among sample sites. While silver carp diets overlapped with native fishes, the impact of this possible source of competition requires further study to confirm impacts on native fish abundances and body conditions.

In 1998, a 123-pound flathead catfish (Pylodictis olivaris) was captured by a recreational angler from Elk City Reservoir, Montgomery County, Kansas. This fish was recognized as the all-tackle world record, and the record has persisted through the time this article was published in fall, 2016. The fish was frozen after capture until it was presented to Kansas Department of Wildlife, Parks, and Tourism in 2016 for further examination. It was concluded that the fish was at least 22 years old, grew rapidly, was most likely male, and had recently consumed a bigmouth buffalo (Ictiobus cyprinellus). Results presented herein provide evidence of rapid growth possible in flathead catfish and help to foster a greater understanding of the species' natural history.

Nonnative bigheaded carps are established in the Mississippi River and there is substantial concern about their potential entry into the interconnected Laurentian Great Lakes. While electrical barriers currently exist as a preventative measure, there is need for additional control mechanisms to promote barrier security through redundancy. We tested the effectiveness of infused carbon dioxide gas (CO2) as a tool to influence the movement and behavior invasive bigheaded carps, namely Bighead Carp Hypophthalmichthys nobilis and Silver Carp H. molitrix, as well as native Bigmouth Buffalo Ictiobus cyprinellus, Channel Catfish Ictalurus punctatus, Paddlefish Polyodon spathula, and Yellow Perch Perca flavescens in an experimental pond. Individuals were monitored with acoustic telemetry before, during, and after CO2 addition to the pond. We noted distinct changes in fish behavior following CO2 addition. Each species except Paddlefish maintained farther distances from the CO2 infusion manifold relative to ...

The information regarding the fish species occurrence in rivers and lakes depends on the quantity and quality of ichthyofaunal surveys. Non-native buffalo fishes, Ictiobus cyprinellus and I. niger (Catostomidae) were introduced to pond aquaculture in the 20th century but since that time they have never been recorded from the natural environment in Europe. Forensic analysis was performed using online data from Czech anglers websites to test whether these fishes were ever caught. In total 13 records were obtained but only 3 were verified in terms of species identification, locality and date. The found records are scattered throughout the area of Czechia and they are without an obvious distribution pattern. The analysis of online fishing web sites can be considered a suitable source of additional information on the occurrence of fishes.

Invasive species are considered the second largest threat to native biodiversity, and ecosystem function and services. One pair of global invaders, bighead, Hypophthalmichthys nobilis, and silver carp, H. molitrix, (collectively referred to as Asian carps) have been introduced throughout the world, and are invading three prairie stream tributaries to the Missouri River in the United States. There is a paucity of knowledge and understanding about Asian carp population characteristics and biology in North America. As such, we documented spatial and temporal trends in population dynamics (i.e., density, size structure, age, growth and condition) of Asian carps in three tributaries to the Missouri River in South Dakota: Big Sioux, James and Vermillion from 2009 to 2012. Finally, native planktivore (i.e., gizzard shad, Dorosoma cepedianum, bigmouth buffalo, Ictiobus cyprinellus, and emerald shiner, Notropis atherinoides) characteristics were examined using condition (Fulton’s K). Overall, 469 silver carp and eight bighead carp were collected using boat electrofishing and mean catch-per-unit-effort of silver carp increased annually. The three rivers’ populations were similar in length frequencies. Silver carp growth was faster initially than later ages and overall was slower than Middle Mississippi River populations. Recruitment of silver carp was erratic with the 2010 year class dominating 91% of catches. Silver carp condition was also similar across rivers, seasons, and years. South Dakota silver carp populations were predicted from a length-weight regression to be lighter than the Gavins Point reach population of the Missouri River, and heavier than both the middle Mississippi and the Illinois River populations. Additionally, mean catch-per-unit-effort for bigmouth buffalo and emerald shiner decreased over the study period. Continued monitoring and research on this newly invading population of Asian carps will provide additional invaluable insight into complex invasive species, assist with understanding Asian carps population dynamics during and after an invasion, and expose the potential negative impacts Asian carps may be having on prairie stream ecosystems.

To better understand potential diet overlap among exotic Asian species of carp and native species of filter-feeding fishes of the upper Mississippi River system, microscopy was used to document morphological differences in the gill rakers. Analysing samples first with light microscopy and subsequently with confocal microscopy, the three-dimensional structure of gill rakers in Hypophthalmichthys molitrix, Hypophthalmichthys nobilis and Dorosoma cepedianum was more thoroughly described and illustrated than previous work with traditional microscopy techniques. The three-dimensional structure of gill rakers in Ictiobus cyprinellus was described and illustrated for the first time.

The determination if fish movement of potadromous species is impeded in a river system is often difficult, particularly when timing and extent of movements are unknown. Furthermore, evaluating river connectivity poses additional challenges. Here, we used large-scale, long-term fish movement to study and identify anthropogenic barriers to movements in the Lake Winnipeg basin including the Red, Winnipeg, and Assiniboine rivers. In the frame of the project, 80 Bigmouth Buffalo (Ictiobus cyprinellus) and 161 Channel Catfish (Ictalurus punctatus) were tagged with acoustic transmitters. Individual fish were detected with an acoustic telemetry network. Movements were subsequently analyzed using a continuous-time Markov model (CTMM). The study demonstrated large home ranges in the Lake Winnipeg basin and evidence of frequent transborder movements between Canada and the United States. The study also highlighted successful downstream fish passage at some barriers, whereas some barriers limited or completely blocked upstream movement. This biological knowledge on fish movements in the Lake Winnipeg basin highlights the need for fish passage solutions at different obstructions.

Some species of fish are more tolerant of rotenone, a commonly used non-specific piscicide, than others. This species-specific tolerance to rotenone has been thought to be associated with the uptake and the efficiency at which the chemical is detoxified. However, rotenone stimulates oxidative stress and superoxides, which are also toxic. Understanding the modes in which fish physiologically respond to rotenone is important in developing improved protocols for its application in controlling aquatic nuisance species. Using a molecular approach, we investigated the physiological and molecular mechanisms of rotenone resistance. Species-specific responses were observed when rotenone-sensitive silver, Hypophthalmichthys molitrix, and both rotenone-resistant bighead carp, Hypophthalmichthys nobilis, and bigmouth buffalo, Ictiobus cyprinellus, were exposed to rotenone. Rotenone levels in plasma were highest 90 min after exposure in both silver carp and bigmouth buffalo, but bigmouth buffalo tolerated over twice the burden (ng mL(-1) g(-1)) than silver carp. Expression of genes related with detoxification (cyp1a and gst) increased in silver carp, but either decreased or remained the same in bighead carp. Genes linked with oxidative stress in the cytosol (gpx, cat and sod1) and hsp70 increased only in silver carp after a 6-h exposure. Expression of genes associated with oxidative stress in the mitochondria (sod2 and ucp2) differed between silver carp and bighead carp. Expression of sod2 changed minimally in bighead carp, but expression of ucp2 linearly increased to nearly 85-fold of the level prior to exposure. Expression of sod2 and ucp2 did not change until 6 h in silver carp. Use of sod1 and sod2 to combat oxidative stress results in hydrogen peroxide production, while use of ucp2 produces nitric oxide, a chemical known to inhibit apoptosis. We conclude that the mechanism at which a fish handles oxidative stress plays an important role in the tolerance to rotenone.

Non-native, Asian carps bighead Hypophthalmichthys nobilis and silver Hypophthalmichthys molitrix have been present in the Illinois River since the early 1990s. The Long-Term Resource Monitoring Program (LTRMP) has been collecting bighead and silver carps in routine monitoring of the La Grange Reach, Illinois River, since 1995 and 1998, respectively. Despite variable recruitment, Asian carps abundance and biomass have increased since 2000, as evidenced by commercial landings, and Asian carps now dominate the fish community on La Grange Reach. Previous research suggests dietary overlap among bighead and silver carps and two native Illinois River fishes, gizzard shad Dorosoma cepedianum and bigmouth buffalo Ictiobus cyprinellus. Total length and mass data from c. 5000 fishes were used to test for changes in gizzard shad and bigmouth buffalo body condition after Asian carps establishment and investigate potential competitive interactions and changes in fitness. Analyses revealed significant declines in body condition of gizzard shad (� 7%) and bigmouth buffalo (� 5%) following the Asian carps invasion from 2000 to 2006. Segmented regression analyses showed no significant change in the rate of decline in gizzard shad condition after 2000, whereas the rate of decline in bigmouth buffalo condition increased significantly after 2000. Statistically significant differences in gizzard shad condition after Asian carps establishment (2000–2006) was observed, whereas condition of bigmouth buffalo was significantly lower in all years following Asian carps establishment as compared to 2000. Declines in gizzard shad and bigmouth buffalo condition were significantly correlated with increased commercial harvest of Asian carps and poorly correlated with other abiotic and biotic factors (e.g. temperature, chlorophyll a and discharge) that may influence fish body condition. These results may suggest that Asian carps are influencing native planktivore body condition, and future research should focus on determining whether food is limited in the Illinois River for native planktivores and other fish species.

Effects of the starting time and duration of cold shock, as well as the source of heterogenic sperm on the percentage of viable gynogenic larvae (PVGL) in tench were studied. The DNA in sperm of red common carp (Cyprinus carpio var singuonensis) was inactivated by ultraviolet radiation prior to use to induce meiotic gynogenetic development in tench. In experiment 1, tench eggs were cold-shocked for 30 min starting at 1, 3, 5, 7, 10 and 15 min post activation. In experiment 2, cold shock began 5 min after activation and lasted for 10, 20, 30, 40, 50 min, respectively. Each experiment was run in triplicate using 3 tench females, and one group not treated with cold shock was included in each experiment to serve as a control group. In experiment 3, sperm of bigmouth buffalo (Ictiobus cyprinellus), red common carp or grass carp (Ctenopharyngodon idella) was used to induce gynogenesis in tench with a 20-min cold shock starting 5 min post activation. The results showed that PVGL from the control group was very low (0.11-0.47%). In experiment 1, the highest average PVGL (9.60%) was observed when cold shock treatment was applied 5 min post activation. When cold shock treatment was started 5 min post activation, duration of cold shock affected PVGL. Cold shock lasting 20 min resulted in the highest average PVGL (12. 57%) among the selected duration of cold shock studied in experiment 2. The average PVGL was 2.3, 8.6, and 9.3%, respectively, for eggs induced by sperm of bigmouth buffalo, red common carp and grass carp. Average PVGL was significantly lower for eggs induced by sperm of bigmouth buffalo, compared with that for eggs induced by sperm of the other two species. However, average PVGL were similar for eggs induced by sperm of red common carp and grass carp. In summary, the optimal conditions for gynogenesis in tench include the use of irradiated sperm of grass carp to activate the eggs and cold shock of 20 min starting 5 min post activation. Since female tench grow much faster to a larger size than male tench, gynogenesis of tench holds great potential for production enhancement.

In 1997 and 1998, we sampled the Missouri River, North Dakota to determine if anthropogenic disturbances had influenced catostomid species composition and feeding ecology. We compared two distinct river segments, the Missouri River between the mouth of the Yellowstone River and Lake Sakakawea (the Yellowstone–Sakakawea segment (YSS)), a moderately altered segment and the Missouri River between Garrison Dam and Lake Oahe (the Garrison–Oahe segment (GOS)), a highly altered segment. The segments exhibited greatly different sucker communities. Bigmouth buffalo, Ictiobus cyprinellus, smallmouth buffalo, Ictiobus bubalus, and river carpsucker, Carpiodes carpio, represented 94% of the sucker catch in the YSS, whereas in the GOS, white sucker, Catostomus commersoni, and longnose sucker, Catostomus catostomus, constituted 98% of the sucker catch. In the YSS, high zooplankton densities led to greater sucker zooplanktivory and food niche overlap than in the GOS. Intense anthropogenic disturbances to the GOS are associated with the differences in sucker species composition, prey density and composition, and sucker feeding ecology between the two segments.

Summary Natural diets of tench (Tinca tinca L.), carp (Cyprinus carpio L.) and bigmouth buffalo (Ictiobus cyprinellus Val.) were studied to determine food competition among them in polyculture stocks of two different densities. Tench diet consisted mainly of zooplankton (43.8%) and bottom sediments (21.2%). In contrast, carp diet consisted mainly of bottom items including plant debris and detritus (68.8%), which dominated over zooplankton (19.1%). In bigmouth buffalo, most food bulk comprised zooplankton (80.7%). Thus, the resulting food competition (i.e. similarity) was most pronounced between tench and carp (60.8%) and between tench and bigmouth buffalo (47.4%). When comparing growth performance of the three cultured species, the ratios between stocking and harvesting size were: in normal stocking density (392 kg ha−1) 1.72, 3.67 and 2.13, and in doubled stocking density (777 kg ha−1) 1.07, 2.33 and 2.16 in tench, carp and bigmouth buffalo, respectively.

The complete mitochondrial genome of Ictiobus cyprinellus was first determined by a polymerase chain reaction-based sequencing method in this study. The mitochondria was 16,611 bp in length, including 13 protein genes, 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes and 1 control region. All genes were encoded on the heavy strain except for ND6 and eight tRNA genes. The gene arrangement of I. cyprinellus was similar to those found in the other Catostomidae species. Base composition of the heavy strain was A (29.40%), T (24.86%), C (27.96%), G (17.78%) and with A + T bias of 54.26%.

Relative weight (W r) is one of several condition indices used to assess the general health of fishes. Standard weight (W s) equations are required to calculate W r, but are unavailable for many nongame and riverine fish species. Therefore, we developed W s equations for the following taxa: longnose gar Lepisosteus osseus, spotted gar L. oculatus, common carp Cyprinus carpio, bigmouth buffalo Ictiobus cyprinellus, river carpsucker Carpiodes carpio, shorthead redhorse Moxostoma macrolepidotum, smallmouth buffalo I. bubalus, white sucker Catostomus commersoni, black bullhead Ameiurus melas, brown bullhead A. nebulosus, flathead catfish Pylodictis olivaris, white catfish A. catus, yellow bullhead A. natalis, white perch Morone americana, yellow bass M. mississippiensis, green sunfish Lepomis cyanellus, rock bass Ambloplites rupestris, and warmouth L. gulosus. These W s equations were evaluated with statistical validation approaches similar to previously defined regression-line-percentile equations. ...

During early life stages, fish in the Mississippi River system may become stranded by shoreline drawdowns induced by the passage of commercial vessels. We examined the stranding of larval shovelnose sturgeon Scaphirhynchus platorynchus, paddlefish Polyodon spathula, and bigmouth buffalo Ictiobus cyprinellus and of juvenile blue catfish Ictalurus furcatus, largemouth bass Micropterus salmoides, and bluegill Lepomis macrochirus in a laboratory flume. Stranding was measured at three vertical drawdown rates (0.76, 0.46, and 0.21 cm/s) and two bank slopes (1:5 and 1:10). Blue catfish, shovelnose sturgeon, and paddlefish were not tested at both bank slopes. Susceptibility to stranding varied among species and was independent of drawdown rate. At a slope of 1:5, shovelnose sturgeons had the highest stranding percentage (66.7%), followed by paddlefish (38.0%), bluegills (20.0%), bigmouth buffalo (2.2%), and largemouth bass (0.0%). At 1:10, blue catfish had the highest stranding percentage (26.7%), follow...

Lake and fish survey data (1991–1992) were compiled for 23 eastern South Dakota natural lakes to provide a basis for preliminary investigation of black bullhead (Ameiurus melas) populations. Survey data contained numerous physical and chemical variables describing lake environments and relative abundance and sue structure of the primary fish species present. Analyses indicated that abundance of black bullheads increased with decreasing lake size (area, depth and volume), increasing nutrients (e.g., total and dissolved phosphorus), and decreasing transparency. Overall, models of biotic variables indicated that black bullhead abundance was negatively associated with abundance of bigmouth buffalo (Ictiobus cyprinellus) and walleyes (Stizostedion vitreum), but positively associated with northern pike (Esox lucius) and common carp (Cyprinus carpio) abundance. Black bullhead sue structure was inversely related to the abundance of common carp, northern pike and yellow perch (Perca flavescens). Black bul...

Hepatocellular hemosiderosis was observed in several species of fish associated with mixed chemical pollution in a Mississippi River Basin ecosystem. Three species of buffalo fish—smallmouth buffalo ( Ictiobus bubalus ), bigmouth buffalo ( Ictiobus cyprinellus ), and black buffalo ( Ictiobus niger )—were collected from a contaminated site, Devil's Swamp, and a control site, Tunica Swamp, both near Baton Rouge, Louisiana. Liver, kidney and spleen were examined histologically. Hepatocellular iron overload was observed in smallmouth buffalo and bigmouth buffalo from Devil's Swamp. Smallmouth buffalo from Tunica Swamp had no stainable iron in the hepatocytes. Bigmouth buffalo from Tunica Swamp had trace amounts of stainable iron in the hepatocytes. Black buffalo from both Devil's Swamp and Tunica Swamp had no stainable iron in the hepatocytes. Iron could accumulate in sediment where it enters the food chain through benthic organisms. Analyses of water and sediment from both study sites revealed similarly high concentrations of iron. The pollutants in the Devil's Swamp may have affected the iron absorption and metabolism in smallmouth buffalo and bigmouth buffalo. The variation in the presence of stainable iron in the liver of three species of buffalo fish may indicate significant interspecies variation in the iron absorption and metabolism under conditions of mixed pollution.

Argulus americanus, A. flavescens, A. lepidostei, and A. japonicus are reported from Illinois for the first time. Gizzard shad (Dorosoma cepedianum) is a new host record for A. japonicus, bigmouth buffalo (Ictiobus cyprinellus) is a new host record for A. catostomi, and black crappie (Pomoxis nigromaculatus) is a new host record for A. stizostethii. Eight species, A. americanus, A. appendiculosus, A. catostomi, A. flavescens, A. japonicus, A. lepidostei, A. mississippiensis, and A. stizostethii, have been recorded from 13 Illinois fish species. Ciliated protozoans (Epistylis or Opercularia) were observed on four Argulus spp., and crustacean shell disease was observed on five species.

Two species of buffalo fish, smallmouth buffalo (Ictiobus bubalus) and bigmouth buffalo (Ictiobus cyprinellus), were collected from a contaminated (multiple metals and organic chemicals) Mississippi River Basin ecosystem, Devil's Swamp and a control site, Tunica Swamp, both near Baton Rouge, Louisiana, USA. The buffalo fish were examined for general health and histopathological effects. This research consists of an analysis of the prevalence of infectious and non-infectious disease from the contaminated vs the relatively uncontaminated control site. Tissue burdens were also determined by chemical analysis of buffalo fish muscle (fillets) samples. Both bigmouth buffalo (BMB) and smallmouth buffalo (SMB) from Devil's Swamp accumulated metals in muscle tissue and generally had a higher prevalence of gill lesions than fish collected from the control site, Tunica Swamp. SMB from Devil's Swamp had higher prevalences of lesions than BMB from Devil's Swamp. The primary types of infectious gill lesions observed in the buffalo fish were protozoan infections in the gill filament cartilage and gill lamellae. Chondrolysis, chondritis and bronchitis were associated with parasitic infection. Eosinophils were the predominant cell type involved with bronchitis and chondritis. The proliferative lesions observed were chondroplasia, chloride cell hyperplasia, mucus cell hyperplasia, and epithelial cell hyperplasia and fusion. Based on these preliminary findings, SMB appeared to be a potentially sensitive biomarker of exposure.

An overabundance of common carp Cvprinus carpio and bigmouth buffalo Ictiobus cyprinellus in North and South Heron lakes, Minnesota, has hindered production of food plants for waterfowl. These shallow (maximum depth, 1.5 m), turbid lakes are partially drawn down each winter. Common carp were radio-tracked in both lakes during the winters of' 1991 and 1992 to monitor their movements and survival. Four of six radio-tagged fish died during the first winter because of low water, but all of an additional 12 radio-tagged common carp survived the second winter. The fish overwintered in water 28–50 cm deep under about 40 cm of ice cover. To assess the ability of an electrical barrier across the outlet stream to prevent migration into the Heron lakes basin, 1,600 common carp and bigmouth buffalo were marked with dart tags and released downstream from the barrier. No tagged fish were among the 3,376 fish caught upstream from the barrier. Catches of the two species per unit gillnetting effort in South Heron...

We report collections of the bighead carp, Hypophthalmichthys nobilis (Richardson, 1845) in the Mississippi River in Missouri and Illinois between 1991 and 1994. In all, we collected 48 specimens ranging from 18 to 790 mm total length. Young-of-the-year fish were caught in 1992 and 1994, which suggests that the species is able to reproduce in the Mississippi River and may become established. Because H. nobilis is a low level filter feeder, its presence may affect other filter feeding fishes such as the paddlefish (Polyodon spathula), bigmouth buffalo (Ictiobus cyprinellus), and gizzard shad (Dorosoma cepedianum). Further research is needed to confirm that the species is established and what its biological impact will be.

Tag retention was measured for paddlefish Polyodon spathula, channel catfish Ictalurus punctatus, blue catfish Ictalurus furcatus, smallmouth buffalo Ictiobus bubalus, and bigmouth buffalo Ictiobus cyprinellus. Fish were captured in 1986 and 1987, triple-tagged with spaghetti tags (Floy FT-4 lock-on), anchor tags (Floy FD-6813), and fin or opercular marks, and released into Energy Lake, Kentucky. After testing for homogeneity, we constructed spaghetti tag retention curves for combined buffalo species and for combined catfish species. Fifty percent of spaghetti tags were lost from buffaloes after 190 d and from catfish after 250 d. Relative tag retention rates after 540 d were higher for anchor than for spaghetti tags on buffalo fish (97 versus 47%) but not different for catfish (74 versus 69%) and paddlefish (97 versus 95%). Spaghetti tags were retained for as long as 4.1 years by channel catfish and 5.2 years by paddlefish. Anchor tags were retained for as long as 3 years by paddlefish, 4.1 year...

During the summers of 1972–73, 10 fish species were evaluated as predators against larvae of the dark rice field mosquito, Psorophora confinnis (Lynch-Arribalzaga), near Stuttgart, Ark. Stocking rates were 0.02, 0.03, and 0.06 fish/ft2. At the lowest stocking rate green sunfish, Lepomis cyanellus Rafinesque, reduced larval numbers by 89.7% and were significantly more effective than adult mosquitofish, Gambusia affinis (Baird and Girard). The white amur, Ctenopharynogodon idella Valenciennes, was intermediate in effectiveness when compared with the above. At 0.03 fish/ft2, green sunfish reduced larvae by 99.2% and were significantly more efficient than juvenile mosquitofish, which had little effect on the larval population. At the 0.06 fish/ft2 rate mosquitofish; white amur; Israeli carp, Cyprinus carpio L.; and hybrids (Israeli carp × goldfish) were significantly more effective than bigmouth buffalo, Ictiobus cyprinellus (Valenciennes); black buffalo, Ictiobus niger (Rafinesque); goldfish, Carassius auratus (L.); or juvenile mosquitofish. Recovery counts of fish indicated that fish survived under natural conditions in Arkansas rice fields.

Chinese methods of fish culture were evaluated for potential use in animal waste management, pollution control, and the production of protein. Two ponds were stocked with grass carp (Ctenopharyngodon idella), silver carp (Hypophthalmichthys molotrix), bighead carp (Aristichthys nobilis), carp (Cyprinus carpio), northern largemouth bass (Micropterus salmoides salmoides), channel catfish (Ictalurus punctatus), and the hybrid of bigmouth buffalo female (Ictiobus cyprinellus) and black buffalo male (I. niger). One pond (0.127 hectare) received the total wastes from five growing pigs (about 39 pigs/hectare of water area), the other pond (0.121 hectare) received the wastes from eight pigs (66 pigs/hectare). Two consecutive lots of pigs were fattened during the study. Over a fish-growing period of about 170 days (May to October 1975) the net increments in fish biomass were 2,971 kg/hectare in the 0.127-hectare pond and 3,834 kg/hectare in the 0.121-hectare pond. A beneficial influence by the fish on wat...

Spatial separation of fishes in the littoral zone of a turbid prairie lake (Clear Lake, Iowa) was assessed with gill nets and fyke nets. Catch per unit of effort was used to determine differences among habitat types, sampling times within a 24 h period, and sampling months. Four of 10 species examined were significantly more numerous in one of the three habitats — nonvegetated, vegetated, or gravel-rock substrate. Black bullhead (Ictalurus melas) and bigmouth buffalo (Ictiobus cyprinellus) were most abundant in vegetated areas, yellow bass (Morone mississippiensis) in gravel-rock areas, and channel catfish (Ictalurus punctatus) in both non-vegetated and gravel-rock areas. Temporal patterns in habitat use were indicated for these four species, as well as yellow perch (Perca flavescens), white bass (Morone chrysops), common carp (Cyprinus carpio), walleye (Stizostedion vitreum vitreum), black crappie (Pomoxis nigromaculatus), white sucker (Catostomus commersoni).

Fish samples were collected annually with rotenone in coves in Beaver Lake, Arkansas, to (1) detect changes in species composition, relative abundance, and standing crops, (2) explore interactions between important groups of species and their physical environment, and (3) describe trends in the total fish population in the reservoir during the first 18 years of impoundment. Fish recovered after treatment of coves with rotenone indicated that the number of species decreased after impoundment. Twelve species showed a general increase in abundance during the period, six species decreased, and three species disappeared-yellow bullhead (Ictalurus natalis), black bullhead (Ictalurus melas), and mooneye (Hiodon tergisus). Of five species introduced into the lake-striped bass (Moroue saxatilis), bigmouth buffalo (Ictiobus cyprinellus), smallmouth buffalo (Ictiobus bubalus), blue catfish (Ictalurus furcatus), and threadfin shad (Dorosoma peteneuse)- only threadfin shad made a major contribution to the tot...

The paper deals with some results of experimental acclimatization of American channel catfish and bigmouth buffalo in U.S.S.R. waters. Attention is focused on the biological characteristics such as growth, nutrition, maturation, etc. of the species, under new environmental conditions. Consideration is given to biotechniques for rearing the introduced species in Ukrainian inland waters.

Aquarium-held bigmouth buffalo Ictiobus cyprinellus (Valenciennes) were fed the blue-green alga Spirulina platensis (Nordstedt) at a daily rate of 29 g dry weight/kg body weight for 28 days. Daily growth was 14 g/kg body weight, and food conversion was 2.0. Tilapia aurea (Steindachner) also was fed this blue-green alga; growth and food conversion were similar to those found for bigmouth buffalo. Fresh Spirogyra sp. fed to grass carp Ctenopharyngodon idella Valenciennes resulted in poor growth, and food conversion was about 10.

The field study of the bigmouth buffalo (Ictiobus cyprinellus (Valenciennes)), conducted mainly in 1955 and 1956, was concentrated on two small eutrophic lakes in the Qu'Appelle River drainage of Saskatchewan. The bigmouth buffalo reaches its northern limit of range in the Qu'Appelle drainage. Migration into Saskatchewan was probably through postglacial connections at the headwaters of the Mississippi and Red River systems. In the lakes studied, the species prefers water shallower than 5 m.The relation of standard length to fork length and of fork length to weight is presented graphically, and the latter described by the equation: weight in pounds = (0.00097 fork length in inches)2.91. Length–frequency distributions and age determinations from scale reading show that the population studied was largely the very successful 1948 year-class, produced in a year of extensive flooding. Annulus formation occurred during the second or third week in June. Growth of the 1948 year-class in Pasqua Lake was extremely slow, probably influenced by the cool climate and population density here.Food of young buffaloes was mainly Cladocera and Copepoda. Larger buffaloes ate about 75% Entomostraca and 15% chironomids, the latter more important as the size of fish increased. Analysis of the living habits of the food eaten, and the feeding mechanism of the buffalo, shows that they occupy a food niche overlapping both bottom feeders and limnetic plankton feeders.Sexual maturation, especially of females, was extremely slow both in age and size as compared with southern populations. Examination of gonads suggests spawning occurs about May 18–25. Egg measurements indicate that females do not all spawn each year. The contention by other investigators that spawning is "triggered" by addition of fresh water analogous to normal spring floods of the Mississippi River is supported by the present study.The population in the Qu'Appelle drainage is probably dependent on the very sporadic production of strong year-classes. A more stable population would require association with regular spring floods of a nearby river or marsh. Commercial removal from the viewpoint of greatest productivity is most economical at the smallest marketable size, as yearly weight gains are probably more than offset by natural mortality.

A hematological study was made based on 10 specimens each of the buffalofishes Ictiobus cyprinellus and I. bubalus (Catostomidae). Average results of analyses of selected blood characteristics of I. cyprinellus and I. bubalus, respectively, were: hemoglobin content, 7.8 and 8.5 g/100 ml; erythrocyte count, 1.08 and 1.28 millions/mm2; hematocrit, 34.6 and 32.9%; mean corpuscular hemoglobin, 67 and 64 μμg; and leucocyte count, 23916 and 29004 cells/mm3. Types of leucocytes noted were lymphocytes, neutrophils, "secretory granulocytes," eosinophils, and thrombocytes. No basophils were found. The secretory granulocyte is apparently derived from the neutrophil series. The status of the secretory granulocyte in buffalofishes is discussed with reference to pertinent literature.

Food habits and food selectivity of bigmouth buffalo, Ictiobus cyprinellus, in Lake Poinsett, South Dakota were studied from January through November 1968. Food of bigmouth buffalo fry ranging from 12.5 to 21.0 mm total length was primarily benthic organisms. Food of sub-adult and adult bigmouth buffalo ranging from 236 to 833 mm total length was primarily zooplankton. Most planktonic organisms were consumed in about the same proportion as they were available. Selectivity was greatest for adult Daphnia pulex, the largest food item present, and least for calanoid copepods. The bigmouth buffalo in Lake Poinsett might best be described as an indiscriminate planktivor throughout most of its life history.

Three species of buffalofish from Apache and Roosevelt Lakes on the Salt River (Gila River System), Arizona, were examined for helminth parasites. They are Bigmouth buffalofish Ictiobus cyprinellus, Smallmouth buffalofish I. bubalus, and Black buffalofish I. niger. All host species were infected with Nematobothrium texomensis McIntosh and Self, 1955 (Trematoda: Didymozoidae) and Glaridacris confusus Hunter, 1929 (Cestoda: Caryophyllaeidae) (new locality records). In the present paper ecological and morphological data concerning these parasites and their relationship with their fish-hosts are reported. Notes on the feeding behavior and capture of hosts, and processing of parasitic worms are also included.

HAFFNER, R. E. 1952. Zoogeography of the bathypelagic fish, Chauliodus. Syst. Zool. 1(3): 112-133. IVANENKOV, V. N., V. R. VINTOVKIN, AND K. Z. SHATSKOV. 1964. Distribution of oxygen in the water of the northern part of the Indian Ocean. Trudy Inst. Okeanol. 44:115-127. (In Russian. Reprinted in Internat. Indian Ocean Exped., Collected Reprints 1:435-447.) MORROW, J. E., JR. 1961. Taxonomy of the deep sea fishes of the genus Chauliodus. Bull. Mus. Comp. Zool. 125(9):249-294. 1964. Family Chauliodontidae. In: Fishes of the western North Atlantic. Mem.

Monobothrium hunteri sp. n. (Cestoidea : Caryophyllaeidae) is described from Catostomus commersoni (Lacepede) in four states. The adult is described, and a table comparing the four species of Monobothrium is given. The systematics of the genus are briefly discussed and the literature records of M. ingens Hunter are reviewed. The life cycle is unknown. A new species of monozoic tapeworm found in the fish Catostomus commersoni (Lacepede) in central New York by Mackiewicz (1961a) is described in this paper. MATERIALS AND METHODS A nonrandom sample of 506 C. commersoni was examined. Of these, 381 were collected from central New York from July 1955 through June 1958. Localities, with numbers of fish and incidence respectively in parentheses, are as follows: Tompkins Co., Cayuga Lake and feeder streams at Ithaca (114/5); Fall, Cascadilla, and Six-mile creeks at Ithaca (137/2); Salmon Creek near Ludlowville (2/0); Dryden Lake outlet at Dryden (26/5). Onondaga Co., Oneida Lake at Shackelton Point (43/0). Herkimer Co., Bisby and Little Moose lakes near Old Forge (28/0). Oswego Co., Black Creek at Cleveland (18/0); and Cayuga Co., Owasco Lake outlet at Groton (13/0). Of the remaining fish 68 were from the Cornell University fish collection representing the following regions, fish numbers, and incidence: Alberta, Canada (1/0); Delaware (2/0); Kentucky (2/0); Maryland (2/0); New Jersey (2/0); North Carolina (17/4); Ohio (6/0); South Carolina (1/0); South Dakota (2/0); Tennessee (11/0); Virginia (7/0); West Virginia (11/1); and Wyoming (4/1). Five additional preserved fish from Michigan and 52' others from Pennsylvania were negative. Preserved fish ranged in total length from 92 to 419 mm; nonpreserved, 28 to 527 mm. Fish were collected in both summer and winter. Received for publication 15 February 1963. * Modified from a thesis submitted to the Graduate School of Cornell University in partial fulfillment of the requirements for the degree of Doctor of Philosophy. t Present address: Department of Biology, State University of New York at Albany, Albany. Cestodes from preserved fish were sometimes badly distorted and not suitable for critical morphological studies. Living worms were first placed in 0.7% saline to observe the scolex movements before dropping them in hot AFA, 10% formalin, or Bouin's fluid. Cross, sagittal, and frontal sections of both mature and immature worms were made. Measurements are based on relaxed, unflattened specimens. Testes and vitellaria measurements on a single worm were obtained by taking the mean of 30 follicles consisting of a nonrandom sample of the ten anterior, middle, and posterior follicles. Material examined included whole mounts of 14 mature and 20 immature worms; serial sections of 4 mature and 6 immature worms. Comparative material of Monobothrium wageneri Nybelin, 1922 consisted of three whole mounts of mature worms and sections of one other from Tinca tinca (L.) Odra River, Poland, determined by and obtained from Dr. Janiszewska, Wroclaw, Poland; and six slides of serial sections of worms from the type locality in Italy from Dr. Nybelin's collection. Comparative material of M. ingens Hunter, 1927 consisted of the type (whole mount, USNM 51176), a single whole mount of a mature worm from Ictiobus cyprinellus (Val.), and three immature worms from Carpiodes carpio (Raf.) from St. Croix River, Minnesota, in the collection of T. Jensen. The M. ingens reported by Bangham and Venard (1942), Self and Campbell (1956), and Krueger (1954) could not be obtained. Examples of M. auriculatum Kulakovskaja, 1961 could not be obtained. Monobothrium hunteri sp. n. Specific diagnosis (N = size of sample measured): Adults (N = 9) from 6.8 to 21 mm long by 0.5 to 1.3 mm wide at the male gonopore. Immature worms (N = 5) from 1.7 to 7 mm long by 0.3 to 0.7 mm wide at the male gonopores. Scolex round in cross section, lacking longitudinal