Aquatic parasites cause disease in economically and culturally important Klamath River salmonids Oncorhynchus spp., and the myxozoan parasite Ceratonova shasta has been linked to high juvenile salmonid mortality. Because C. shasta requires the freshwater annelid Manayunkia occidentalis to complete its life cycle, management approaches have focused on disrupting annelid populations to reduce C. shasta

Effective stocking programs are an essential part of maintaining most high-quality tributary steelhead Oncorhynchus mykiss fisheries in the Great Lakes, requiring sufficient numbers of stocked fish to survive, imprint, and return as adults. New York’s Lake Erie tributaries have long supported popular and economically important recreational steelhead fisheries, attracting anglers from across the country

For many years bait has been banned in catch-and-release trout fisheries owing to anticipated high rates of hooking mortality. Recent studies that have been conducted in streams have found relatively low rates of hooking mortality. The objective of this study was to quantify the rates of hooking and handling mortality of stocked trout that were caught by recreational anglers using the terminal tackle

Supplemental stocking of crappie is a primary management strategy in many small southern reservoirs, but survival and contribution to the year-class in these systems is not known. We assessed the contribution of hatchery fish to the age-1 year-class within established crappie populations in four reservoirs ranging 29–74 ha in surface area. Chemically marked White Crappie Pomoxis annularis and magnolia

Offshore petroleum platforms provide habitat that is utilized by an array of reef fish that are valuable to both commercial and recreational fishers. However, thousands of offshore platforms have been decommissioned in the Gulf of Mexico over the past decade, with many of the removals being accomplished using explosive severance methods. Here, we estimate the impact of platform removal in the Gulf

Bigheaded carp (Bighead Carp, Hypophthalmichthys nobilis and Silver Carp, Hypophthalmichthys molitrix) are invasive species in the US and have spread throughout much of the Mississippi River Basin. Population abundance upstream of Lock and Dam 19 (LD19) on the Upper Mississippi River (UMR) has likely been limited by the high-head dam at this location, which restricts all upstream fish passage to the

The Yakama Nation manages a program for reintroducing Sockeye Salmon Oncorhynchus nerka upstream of Cle Elum Dam in the Yakima River basin. The program involves transplanting of a mix of adult Sockeye Salmon from two middle Columbia River donor stocks, Lake Wenatchee (WEN) and Osoyoos Lake (OSO), with the goal of establishing a self-sustaining population in the basin. In 2017, a subset of the transplanted

Basic life history information can be useful for informing management of protected species such as the Pahrump Poolfish Empetrichthys latos, a goodeid (Cyprinodontiformes) endemic to the Mojave Desert in southern Nevada, USA, and the last surviving remnant of Empetrichthys. Critically endangered and extirpated from its native range, E. latos has been managed among constructed refuge habitats since

Shovelnose Sturgeon Scaphirhynchus platorynchus were extirpated from the Bighorn River, Wyoming during the 20th century after the construction of two main-stem dams and the resulting modifications to fish passage and flow and thermal regimes. The species was reintroduced to the river between 1996 and 2020, but nothing was known about how these fish used the river and whether they could sustain themselves

Brown Trout Salmo trutta are a popular sport fish, and numerous populations that are unable to successfully reproduce are maintained with supplemental stockings in waters with habitat that can support individual survival (e.g., appropriate thermal refuge). Long-term management of these populations requires understanding of their population dynamics to determine harvest restrictions and stocking rates

Muskellunge Esox masquinongy fisheries have increased in abundance and popularity in numerous southern and mid-Atlantic rivers. However, the paucity of information for these fisheries has limited biologists’ ability to effectively manage these resources. We utilized data from simultaneously conducted fishery dependent tag-return and fishery independent capture-recapture studies to estimate catch-and-release

Fecundity is a necessary metric to assess reproductive potential (e.g., spawning potential ratio and recruitment overfishing) in invasive fishes, yet the direct measurement of fecundity is often difficult, impractical, and time consuming. Therefore, the ability to estimate fecundity from field measurements (i.e., TL, relative weight [Wr], or ovary weight) can be a valuable tool for fisheries managers

Hybridization among the black basses (Micropterus spp.) occurs due to weak postzygotic reproductive barriers and anthropogenic factors such as habitat alteration. Introduction of previously allopatric species can also result in hybrid swarms and in some cases, extirpation of native species. Introgressive hybridization is a major conservation concern for the more range-restricted black basses, which

Columbia River hatcheries release millions of juvenile Chinook Salmon Oncorhynchus tshawytscha, to support fisheries and mitigate for historical productivity declines from dam construction and upriver habitat losses. Recent Federal Biological Opinions for Federal Columbia River Power System operations also have mandated restoration of estuarine rearing habitats to mitigate for mortality of naturally

The Yaqui Catfish Ictalurus pricei is an understudied species, with limited information available on its ecology, distribution, and local habitat use. Native to the southwestern United States and northwestern Mexico, Yaqui Catfish populations are declining, which has prompted listing of the species as threatened in the United States and as a species of concern in Mexico. Water overallocation, habitat

Retention of visible implant elastomer (VIE) was assessed during an evaluation of put-grow-and-take Brown Trout Salmo trutta and Rainbow Trout Oncorhynchus mykiss stockings in Apalachia Reservoir, North Carolina. Visible implant elastomer was injected in the postocular adipose tissue of two sizes (approximately 254 [small] and 356 [large] mm TL) of Brown Trout and Rainbow Trout in November 2012–2015

Accurate estimates of salmonids passing Lower Granite Dam on the Snake River, by species and origin, are a critical input to assessing the status and trends of various populations as well as successful management of fisheries in the Snake River basin. Here, we describe a state-space model that estimates such escapement past a dam by using window counts, PIT tag observations, and data from an adult

Standard weight equations have been proposed for a variety of fishes, including many nongame species. Here, we developed standard weight (Ws) equations for Lake Chubsucker Erimyzon succetta using the traditional regression-line-percentile technique and the newer empirical-percentile method. Length and weight data for 19,727 Lake Chubsuckers from 8 to 42 cm TL and 129 populations were used in the final

The Cape Fear River basin is located along the southeastern Atlantic Slope and is the largest river basin located within North Carolina. Historically, the ictalurid assemblage was characterized by five species of bullhead Ameiurus spp. and three species of madtom Noturus spp. Channel Catfish Ictalurus punctatus were introduced in the early 20th century, followed by Flathead Catfish Pylodictis olivaris

The relationship between the magnitude of reproduction and adult density of pelagically spawning carp (PSC) species (bigheaded carp Hypophthalmichthys spp., Grass Carp Ctenopharyngodon idella, and Black Carp Mylopharyngodon piceus) and the influence of environmental factors on this relationship are valuable information for management and control of these highly invasive cyprinids. Six years of standardized

“Bartram’s Bass” Micropterus sp. cf. coosae is endemic to the upper Savannah River basin of the southeastern United States and is threatened by hybridization with invasive Alabama Bass Micropterus henshalli. Bartram’s Bass have been functionally extirpated from reservoirs, and hybrid individuals have been detected in several tributaries. However, the extent of introgression in tributaries is currently

Substantial work has been conducted to estimate the river length required for recruitment of invasive Grass Carp and bigheaded carp; however, the distance upstream and size of stream required for spawning remain unclear. Adult Grass Carp are regularly captured in Truman Reservoir, Missouri although there have been only unconfirmed sightings of Silver Carp. Fertile diploid Grass Carp are used legally

Catch-and-release ice angling is a popular recreational activity, but little is known about the postrelease behavior of fish in the winter. Cold water temperatures and an ambush hunting strategy may constrain Northern Pike Esox lucius, limiting their postrelease movements to a small area near the capture location. We used manual acoustic telemetry to track 15 Northern Pike ranging from 56 to 98.5 cm

The Black Drum Pogonias cromis is an abundant estuarine-dependent fish that supports recreational and commercial fisheries. We examined the phylogeography and historical demography of the Black Drum along the Atlantic and Gulf of Mexico coasts of the United States using mitochondrial DNA sequences and nuclear DNA microsatellites. Black Drum exhibited high haplotype diversity and low nucleotide diversity

Introduced species can alter the dynamics of food webs, species interactions, populations, communities, and reduce a system’s recreational value. Several reports have documented the establishment of Redside Shiners Richardsonius balteatus into mountain lakes resulting in declines in sizes and abundance of salmonid species. An illegal bait bucket release introduced Redside Shiners to Green Canyon Lake

Condition indices, such as relative weight (Wr), provide a simple method for comparing length–weight relationships among populations. However, no standard weight (Ws) equation has been developed for Utah Chub Gila atraria, a species of important management focus in the Intermountain West. We obtained length–weight data for 30,541 Utah Chub from 24 populations in Idaho, Montana, Utah, and Wyoming. We

Calibrated estimates of fisheries population abundance are vital in the development and appraisal of management actions. Capture–recapture (CR) experiments are invaluable monitoring tools for estimating abundance of biological populations in general. Many researchers, including those studying out-migrating juvenile Chinook Salmon Oncorhynchus tshawytscha in the Klamath Basin of Oregon and California

Muskellunge Esox masquinongy are large, predatory game fish whose association with shallow, complex habitats is well documented, particularly during early life stages. Despite this association, relatively little guidance exists regarding effective sampling of Muskellunge larvae and previous efforts to sample larval Muskellunge have been met with limited success. Therefore, our objective was to determine

Maximum economic yield (MEY) as derived from Schaefer’s bioeconomic model was potentially a major contribution to fishery management but it has been hard to apply to fishery management in reality. Schaefer’s model with fixed catchability and associated linear catch-per-unit-effort (CPUE) does not match the variable nature of catchability resulting from technological progress and schooling behavior

Recent declines in abundance of Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri in the upper Blackfoot River drainage in Idaho coincided with establishment of a nearby nesting colony and increased abundance of American White Pelicans Pelicanus erythrorhynchos (hereafter pelicans). Published pelican predation rates have been estimated to be as high as 70% on Yellowstone Cutthroat Trout in

Catch-curve analyses are routinely used to estimate instantaneous mortality (Z) in fish and as the age-frequency data are often over-dispersed, the application of a variance bias-correction factor has been recommended. The extensions of the Poisson generalized linear model (GLMPoisson) may however constitute a better alternative, as they model the variance (SE) in counts more adequately with their

Restoring stream connectivity by replacing road culverts is a high conservation priority, yet long-term fish passage data aimed to “ground-truth” culvert prioritization methods are lacking. One common tool for prioritizing culvert removals is the protocol developed by the North Atlantic Aquatic Connectivity Collaborative (NAACC), which uses culvert characteristics to estimate barrier severity and fish

Water diversions are very common in agricultural landscapes, providing water to irrigate a diverse range of crops. Larval Pacific Lamprey Entosphenus tridentatus are vulnerable to entrainment during the irrigation withdrawals and can be exposed to desiccation or predation during dewatering at the end of the irrigation season. A customized portable deepwater electrofishing system was deployed to determine

The American Eel Anguilla rostrata is a catadromous fish found in rivers along the East Coast of North America. American Eel populations have declined throughout their range for several reasons, including habitat fragmentation caused by damming, which hinders access to much of their historic lotic habitats. This study examined differences in abundance and size structure across river segments divided

Texas’ Neighborhood Fishin’ Program provides close-to-home angling opportunities within nine large metropolitan areas to increase angling participation among urban constituents. Water bodies (0.4–2.4 ha) are typically stocked with harvestable (≈305 mm TL) Channel Catfish (CCF) Ictalurus punctatus to provide high-catch, successful fishing experiences. However, fish producers have been increasingly rearing

Management of Gulf of Mexico Red Snapper Lutjanus campechanus has been a topic of much scientific debate and intensive public scrutiny. In response to political, public, and management desires for more robust data on Red Snapper populations, a gulfwide initiative commonly referred to as the “Great Red Snapper Count” (GRSC) was funded to estimate the absolute abundance of Red Snapper in the U.S. Gulf

Relative weight (Wr) is an index that is commonly used by fisheries managers to evaluate the condition within and among fish populations. Managers also use Wr comparisons to assess condition dynamics among species. Rather than using population-level mean Wr for comparisons, standard length categories are frequently used to evaluate mean Wr differences among length categories. To establish Wr values

Translocation is one of the most commonly proposed management actions for securing and recovering native fish species. However, the success of native fish translocations has varied widely due to several limiting factors, including the presence of nonnative fishes. The Blue River Native Fish Restoration Project involved construction of a fish passage barrier, removal of nonnative fish, translocation

Adult summer-run steelhead Oncorhynchus mykiss overwinter in freshwater for several months prior to spawning. In systems supporting mixed populations of fisheries and conservation importance, understanding the distribution and survival of pre- and postspawn fish is necessary for informed management. The upper Columbia River supports hatchery-origin components valued by anglers, natural-origin components

The National Marine Fisheries Service is mandated by the Magnuson–Stevens Fishery Conservation and Management Act to implement effective annual catch limits and accountability measures to prevent overfishing. These requirements compel further research into alternative fishing practices that could reduce mortality of sharks (class Chondrichthyes) and allow fishers to release unwanted sharks to the water

Tailwater trout fisheries provide popular and unique opportunities for anglers across the southeastern USA but often suffer from high mortality and low returns to creel. The Sipsey Fork tailwater in Alabama provides such an opportunity and is stocked monthly with Rainbow Trout Oncorhynchus mykiss. However, a recent creel survey found that less than 25% of fish stocked each month were harvested, with

Fish managers must weigh trade-offs among cost, speed, efficiency, and ecological adaptation when deciding how to translocate native salmonids to either establish or genetically augment populations. Remote site incubators (RSIs) appear to be a reasonable strategy, but large-scale evaluations of this method have been limited. We used 129 RSIs to incubate >35,700 eyed embryos of Westslope Cutthroat Trout

Discard mortality studies are considered a primary research priority, particularly for species and fisheries where discard rates are high. Monkfish (the commercial name for Goosefish) Lophius americanus supports the most lucrative finfish fishery in New England, and it is also the second highest bycatch species by weight in the sea scallop dredge fishery. Despite its commercial importance, no data

The American Eel Anguilla rostrata has experienced a marked population decline due to a multitude of threats, including pollution, overfishing, and damming. Government agencies responsible for American Eel management have identified gaps in survey coverage and understanding of habitat needs as critical obstacles to recovery. However, efforts to expand American Eel monitoring are hindered by this species’

The invasive White Perch Morone americana occurs intermittently throughout Kansas and is ubiquitous in three Kansas reservoirs. However, a paucity of information on the effectiveness of sampling gears for providing accurate and precise estimates of size structure and relative abundance for White Perch precludes reasonable assessments of the effectiveness of control measures. The North American standard

Muskellunge Esox masquinongy fisheries in Ohio are maintained through annual stocking of advanced fingerlings (25–30 cm) at nine reservoirs. Voluntary angler catch reporting is the principal method for monitoring (stocking and angling success) these fisheries. During 1960–2007, anglers reported catching over 47,000 Muskellunge by mailing catch cards to the Ohio Department of Natural Resources, Division

Endangered and endemic Razorback Suckers Xyrauchen texanus of the Colorado River basin largely spawn in main-stem rivers and reservoirs. While documenting other native fish use of two intermittent tributaries of the Gunnison River, Colorado, USA, we detected PIT-tagged Razorback Suckers during the 2015–2019 spawning seasons (April–June) and captured reproductively ready individuals. Because the species

Chase boats are used to assist in the capture of Blue Catfish Ictalurus furcatus because they often surface relatively far from the electrofishing boat (electrofisher) when incapacitated by low-frequency, pulsed DC. We conducted this study to determine how chase boat use affects size-related and capture efficiency metrics of Blue Catfish, and we concurrently examined possible confounding effects of

We summarized advancements in Flathead Catfish Pylodictis olivaris biology, fisheries, and management published from 1999-2020. Our goal was to highlight recent advancements in Flathead Catfish research and address information needs for this species to encourage future research. We identified and reviewed 141 papers from 33 peer-reviewed journals, 27 theses/dissertations, and 13 technical reports on

Channel Catfish Ictalurus punctatus were collected during 2018 and 2019 from the Monongahela River in West Virginia using hoop nets to estimate population dynamics. Length, weight, sex, fecundity, and age data were obtained from collected individuals. Population characteristics (e.g., relative abundance, size structure, age structure, growth, etc.) were modeled under three proposed length limits of

Three species of invasive carp—Grass Carp Ctenopharyngodon idella, Silver Carp Hypophthalmichthys molitrix, and Bighead Carp H. nobilis—are rapidly spreading throughout North America. Monitoring their reproduction can help to determine establishment in new areas but is difficult due to challenges associated with identifying fish eggs. Recently, random forest models provided accurate identification

Saugeye (female Walleye Sander vitreus × male Sauger S. canadensis) are stocked annually into Ohio reservoirs to maintain popular recreational fisheries. The growth and recruitment of stocked saugeye are highly variable among years and reservoirs, but the causes of this variability are not well understood. Using a multi-year (2004–2019), multi-reservoir (six reservoirs) data set, we implemented mixed-effects

Flathead Catfish Pylodictis olivaris have been either intentionally or accidentally introduced into Atlantic Slope drainages extending from Florida to Pennsylvania and have quickly become established. In Pennsylvania, Flathead Catfish were first detected in the Schuylkill River at the Fairmont Dam in 1999 and in the Susquehanna River at Safe Harbor Dam in 2002. The species has since moved throughout

Setlines and trotlines are useful tools for sampling catfish populations. These gears offer an alternative to sampling in habitats or conditions that are unsuitable for traditional sampling gears, and they may be capable of sampling a different subset of the population. However, little is known about their efficacy as catfish sampling gear. We developed a standardized method for deploying setlines

The St. Clair and Detroit rivers historically supported abundant fish populations. However, like many river systems, these rivers have been greatly altered through the creation of navigation channels and other anthropogenic disturbances, resulting in the loss of fish and wildlife habitat and declines in native fish populations. To ameliorate this environmental degradation, artificial fish spawning

Catfishes (Ictaluridae) are among North America’s most important ichthyofauna for human consumption and recreation. As such, research on Blue Catfish Ictalurus furcatus, Channel Catfish I. punctatus, and Flathead Catfish Pylodictis olivaris has been abundant in historic and contemporary literature. A common technique for studying catfish involves marking or tagging fish to understand behavior, sampling

The management of invasive Blue Catfish Ictalurus furcatus in Chesapeake Bay tributaries is hindered by the lack of information on its reproductive biology, which is a key component of population models used to forecast abundance. We quantified and compared the reproductive traits of female Blue Catfish from two populations from the tidal reaches of the James and York River subestuaries during 2015–2017

Many adult hatchery‐origin Pacific salmon Oncorhynchus spp. return to their natal river but do not enter the hatchery, instead spawning in the river, where they can have detrimental genetic and ecological effects on naturally reproducing wild populations. This phenomenon is especially well documented in Elk River (Oregon) Chinook Salmon O. tshawytscha based on previous analyses of coded wire tag recoveries

Management agencies commonly stock Channel Catfish Ictalurus punctatus as advanced yearlings instead of fingerlings (age 0) to help reduce potential predation mortality despite uncertainty regarding the degree to which predation limits fingerling poststocking survival. To better understand whether fingerling survival during the first 7 d after stocking—when predation risk is likely greatest—could benefit

The Blue Catfish Ictalurus furcatus is a popular sport fish in its native range and a prolific invasive species in its nonnative range. Low‐frequency electrofishing (LFE) is effective for sampling Blue Catfish, and development of standardized LFE protocols for sampling Blue Catfish is critical for monitoring and management of their populations. However, standardized sampling for Blue Catfish can be