Allen F Mensinger

• PhD
• Professor (Full) at University of Minnesota, Duluth

Understanding the phenotypic consequences of naturally occurring genetic changes, as well as their impact on fitness, is fundamental to understanding how organisms adapt to an environment. This is critical when genetic variants have pleiotropic effects, as determining how each phenotype impacted by a gene contributes to fitness is essential to unde...

There are increasing concerns from scientists and policymakers regarding the potential effects of sound on aquatic life. While mobile species can move away from sound sources, slow moving or sessile organisms are unable to escape. Many species of elasmobranchs are oviparous and deposit egg cases that remain in a fixed position on or near the seabed...

The foraging success and growth of piscivores often depend on environmental light availability. In north-temperate systems, high tannin concentrations limit light, and increasing variability in tannin levels may influence fish foraging behavior, success, growth, and further contribute to varying recruitment trends. To evaluate foraging and growth r...

Successful foraging of piscivores is often dependent upon light availability in their visual habitat and is often influenced by a number of abiotic and biotic factors. In north-temperate lakes, dissolved organic carbon concentrations vary greatly, thus likely influencing foraging success. To understand the impact this has on the walleye (Sander vit...

The round goby (Neogobius melanostomus) is an invasive benthic fish first introduced to the Laurentian Great Lakes in 1990 that has negatively impacted native fishes through increased competition for food and habitat, aggressive interactions, and egg predation. While complete eradication of the round goby is currently not possible, intensive trappi...

Fish bioacoustics, or the study of fish hearing, sound production, and acoustic communication, was discussed as early as Aristotle. However, questions about how fishes hear were not really addressed until the early 20th century. Work on fish bioacoustics grew after World War II and considerably in the 21st century since investigators, regulators, a...

The behaviour of two benthic species, round goby ( Neogobius melanostomus ) and mottled sculpin ( Cottus bairdii ), were examined under natural relevant downwelling light during predatory attacks by Burbot ( Lota lota ) and Smallmouth Bass ( Micropterus dolomieu ). Population declines have been observed for mottled sculpin after round goby invaded...

The oyster toadfish, Opsanus tau, has been a valuable biomedical model for a wide diversity of studies. However, its vocalization ability arguably has attracted the most attention, with numerous studies focusing on its ecology, behavior, and neurophysiology in regard to its sound production and reception. This paper reviews 30 years of research in...

Grass (Ctenopharyngodon idella) and black (Mylopharyngodon piceus) carp were imported to the United States as biocontrol agents in aquaculture facilities; however, due to intentional stocking or accidental release, invasive populations have become established. Invasive bigheaded carps display negative phonotaxis to sound, suggesting acoustic deterr...

Anthropogenic activity and its associated sounds have been shown to incur adverse effects on the behaviour and physiology of a wide range of aquatic taxa, from marine mammals to fishes. Yet, little is known about how invertebrates detect and respond to anthropogenic sound. The hummingbird bobtail squid (Euprymna berryi) has a short lifespan (< 6 mo...

Population divergence is often quantified using phenotypic variation. However, because sensory abilities are more difficult to discern, we have little information on the plasticity and rate of sensory change between different environments. The Mexican tetra (Astyanax mexicanus) is a fish distributed throughout Southern Texas and Northern Mexico and...

Freshwater lake soundscapes yield crucial information regarding biological, geological, and anthropogenic activity, yet is a relatively unexplored area of study. These soundscapes are particularly important to aquatic life that may use sound to navigate, find food, avoid predators, and communicate. Further research is required to understand how aqu...

The inner ear of teleost fishes is composed of three paired multimodal otolithic end organs (saccule, utricle, and lagena), which encode auditory and vestibular inputs via the deflection of hair cells contained within the sensory epithelia of each organ. However, it remains unclear how the multimodal otolithic end organs of the teleost inner ear si...

The soundscapes of marine systems have been studied for decades to determine spatial and temporal patterns of biological, geological, and anthropogenic activity. However, comparatively little is known about freshwater soundscapes. Lake Superior is the world’s largest freshwater lake by surface area and home to a variety of aquatic animals. The Twin...

Vessel sound is now globally recognized as a significant and pervasive pollutant to aquatic life. However, compared to marine environments, there is a paucity of data on sound emitted by vessel activity in freshwater habitats. The Upper Mississippi River (UMR) is home to a diverse array of aquatic life as well as being a key route for barge transpo...

In coastal waters, anthropogenic activity and its associated sound have been shown to negatively impact aquatic taxa that rely on sound signaling and reception for navigation, prey location, and intraspecific communication. The oyster toadfish Opsanus tau depends on acoustic communication for reproductive success, as males produce ‘boatwhistle’ cal...

Piscivorous fishes attack and consume a variety of prey, however few studies have examined interactions of multiple predators with multiple prey species. The situational complexity of foraging at different times of the day was explored by examining the interactions of paired native predators (Burbot Lota lota or Smallmouth Bass Micropterus dolomieu...

Anesthesia is used to sedate aquatic animals during transportation or to immobilize them for surgery. However, most studies have focused on the behavioral effects of induction and recovery, without addressing the effect of anesthetic on neural activity. This study investigated the neural response of anterior lateral line afferent fibers in the oyst...

Due to a mistake during the production process, the online/HTML version of the original article was published under the terms of the Creative Commons Attribution 4.0 International License. The article is not open access and no special license applies. The original article has been corrected.

Many aquatic organisms use vocalizations for reproductive behavior; therefore, disruption of their soundscape could adversely affect their life history. Male oyster toadfish (Opsanus tau) establish nests in shallow waters during spring and attract female fish with boatwhistle vocalizations. Males exhibit high nest fidelity, making them susceptible...

The effects of anthropogenic sound on freshwater animals has received considerably less attention than their marine counterparts. Physical barriers such as dams in rivers and lakes, provide flood protection and generate hydroelectric power, but can also hinder fish movements. Fish that transit navigational locks adjacent to dams are exposed to vess...

Finding effective ways to direct native fish away from anthropogenic hazards and limit the spread of invasive species, without physical intervention, harming non-target fishes or interrupting aquatic commerce is a major challenge for fisheries management. One option is to target fish sensory systems to manipulate behavior using attractive or repuls...

Invasive silver (Hypophthalmichthys molitrix) and bighead (H. nobilis) carp, collectively referred to as bigheaded carps, threaten aquatic ecosystems of the Upper Midwestern USA. Due to the extensive ecological impacts associated with these species, prevention of their further range expansion is the aim for fisheries management. Recent behavioral s...

Monitoring freshwater ecosystems using passive acoustics is a largely unexplored approach, despite having the potential to yield information about the biological, geological and anthropogenic activity of a lake or river system. The state of Minnesota, located in the upper Midwest of the USA and nicknamed ‘land of 10,000 lakes’, provides an interest...

No PDF available ABSTRACT For the oyster toadfish, Opsanus tau, vocal communication and sound detection are critical for reproductive success, however, little is known about how they respond to changes in their acoustic environment. Passive acoustic monitoring was conducted in Eel Pond, MA, USA in the summer months (2017–2019) to investigate vocali...

No PDF available ABSTRACT Monitoring freshwater ecosystems using passive acoustics is a largely unexplored approach, despite having the potential to yield information about the biological, geological and anthropogenic activity of a lake or river system. Minnesota, nicknamed “land of 10 000 lakes,” provides an interesting case study, because of the...

Foraging characteristics of siscowet lake trout (Salvelinus namaycush siscowet) on deepwater sculpin (Myoxocephalus thompsonii) were studied under ecologically relevant downwelling light intensities (9.0 × 108 to 1.62 × 1011 photons m−2 s−1) and emission spectrum (500–510 nm) on varying substrates (gravel, sand, and black fabric). Siscowet reaction...

Visual communication is used widely across the animal kingdom to convey crucial information about an animals' identity, reproductive status, and sex. Although it is well-demonstrated that auditory and olfactory sensitivity can change with reproductive state, fewer studies have tested for plasticity in the visual system, a surprising detail since co...

Non‐physical barriers, including the use of underwater strobe lights alone or paired with sound or bubbles, are being considered as a means to prevent the upstream migration of invasive silver carp Hypophthalmichthys molitrix and bighead carp H. nobilis. To optimize potential optical deterrents, it is necessary to understand the visual sensitivity...

Acoustic communication is vital across many taxa for mating behavior, defense, and social interactions. Male oyster toadfish, Opsanus tau, produce courtship calls, or “boatwhis-tles,” characterized by an initial broadband segment (30–50 ms) and a longer tone-like second part (200–650 ms) during mating season. Male calls were monitored continuously...

A longstanding question in aquatic animal sensory physiology is the impact of self-generated movement on lateral line sensitivity. One hypothesis is that efferent modulation of the sensory hair cells cancels self-generated noise and allows fish to sample their surroundings while swimming. In this study, microwire electrodes were chronically implant...

Studies on the behavioural function of sounds are very rare within heterospecific interactions. John Dory (Zeus faber) is a solitary, predatory fish that produces sound when captured, but has not been documented to vocalize under natural conditions (i.e. in the wild). The present study provides the first in-situ recordings of John Dory vocalisation...

Male oyster toadfish (Opsanus tau) acoustically attract females to nesting sites using a boatwhistle call. The rapid speed of sound underwater combined with the close proximity of the otolithic organs makes inner ear interaural time differences an unlikely mechanism to localize sound. To determine the role that the mechanosensory lateral line may p...

Human‐generated sound affects hearing, movement, and communication in both aquatic and terrestrial animals, but direct natural underwater behavioral observations are lacking. Baited underwater video (BUV) were deployed in near shore waters adjacent to Goat Island in the Cape Rodney–Okakari Point Marine Reserve (protected) or outside the reserve app...

Silver (Hypophthalmichthys molitrix) and bighead (H. nobilis) carp (collectively bigheaded carp) are invasive fish that threaten aquatic ecosystems in the upper Midwest United States and the Laurentian Great Lakes. Controlling bigheaded carp is a priority of fisheries managers and one area of focus involves developing acoustic deterrents to prevent...

Male oyster toadfish, Opsanus tau, produce long duration (250 to 650 ms) sexual advertisement calls or “boatwhistles” during the breeding season. When males are in close proximity, they employ multiple vocalization strategies. They normally alternate the production of boatwhistles to avoid temporal overlap. When the fundamental frequencies of multi...

This conference has provided a venue for the exchange of information on various aspects of aquatic invasive species since its inception in 1990. The conference continues to provide an opportunity for dialog between academia, industry and environmental regulators. Abstract Invasive silver carp (Hypophthalmichthys molitrix) dominate large regions of...

Silver carp (Hypophthalmichthys molitrix), an invasive planktivorous fish species in North America, pose a threat to aquatic ecosystems throughout the Mississippi River Drainage. These fish are well known for their airborne leaps in response to passing watercraft, but the trigger for, and functional significance of jumping remains unknown. The beha...

Recent studies have shown the potential of acoustic deterrents against invasive silver carp (Hypophthalmichthys molitrix). This study examined the phonotaxic response of the bighead carp (H. nobilis) to pure tones (500–2000 Hz) and playbacks of broadband sound from an underwater recording of a 100 hp outboard motor (0.06–10 kHz) in an outdoor concr...

Human generated noise affects hearing, movement and communication in both aquatic and terrestrial animals, but direct natural underwater behavioral observations are lacking. Baited underwater video (BUV) equipped with hydrophones were deployed inside and outside a marine reserve to observe fish behavior during motorboat transits. BUVs were effectiv...

Invasive silver carp (Hypophthalmichthys molitrix) are notorious for their prolific and unusual jumping behavior. Juvenile and adult (~25 kg) carp can jump up to 3 m above the water surface in response to moving watercraft; however, it is unclear what is the trigger that elicits jumping. Broadband sound (0.06 – 10 kHz) recorded from an outboard mot...

The soft-bottom benthic fish community of the St. Louis River and Duluth-Superior Harbor was examined yearly (20 of 23 years) from 1989 through 2011 using bottom trawling. Catch per unit effort (CPUE) and fish lengths were used to assess the impact of the round goby, which appeared in trawl records in 1998, on benthic native fishes. Logperch (_Perc...

The utricular otolith and the mechanosensory lateral line of the toadfish, Opsanus tau, were investigated for sensitivity to multimodal sensory input by recording neural activity from free swimming fish. The utricle was sensitive to horizontal body movement, and displayed broad sensitivity to low frequency (80–200 Hz) sound. The lateral line was se...

Bighead carp (Hypophthalmichthys nobilis), silver carp (H. molitrix) (hereafter: bigheaded carps), and common carp (Cyprinus carpio) are invasive fish causing negative impacts throughout their North American range. To control their movements, non-physical barriers are being developed. Broadband sound (0.06 to 10 kHz) has shown potential as an acous...

The reaction distance, angle of attack, and foraging success were determined for siscowet lake trout (Salvelinus namaycush siscowet) during laboratory trials under lighting conditions that approximated downwelling spectral irradiance and intensity (9.00 × 108–1.06 × 1014 photons m− 2 s− 1) at daytime depths. Siscowet reaction distance in response t...

The invasive Silver Carp (Hypophthalmichthys molitrix) dominate large regions of the Mississippi River drainage and continue to expand their range northward threatening the Laurentian Great Lakes. This study found that complex broadband sound (0–10 kHz) is effective in altering the behavior of Silver Carp with implications for deterrent barriers or...

The Laurentian Great Lakes have been the site of numerous aquatic invasive species such as the sea lamprey, zebra mussel and round goby. To further understand interactions between invasive and native species in situ, competitive interactions between native logperch (Percina caprodes) and invasive round goby (Neogobius melanostomus) were examined us...

The inner ear of fishes contains three paired otolithic endorgans, the saccule, lagena, and utricle, which function as biological accelerometers. The saccule is the largest otolithin most fishes and much of our current understanding on auditory function in this diverse group of vertebrates is derived from anatomical and neurophysiological studies o...

The predator-prey interactions in the offshore food web of Lake Superior have been well documented, but the sensory systems mediating these interactions remain unknown. The deepwater sculpin, (Myoxocephalus thompsoni), siscowet (Salvelinus namaycush siscowet), and kiyi (Coregonus kiyi) inhabit low light level environments. To investigate the potent...

Silver carp (Hypophthalmichthys molitrix) dominate large regions of the Mississippi River Drainage, outcompete native species, and continue to expand northward threatening the Great Lakes. Understanding silver carp behavior is critical to determine effective techniques for controlling this harmful species. Field observations and recordings in Havan...

Although bubble curtains have been proposed many times as practical and inexpensive solutions to hinder the movement of invasive fish, few studies have examined why or how they might work. By understanding how bubble curtains influence fish behavior, management tools could be developed to control movement of invasive fish. In this study, the common...

Sound communication is fundamental to many social interactions and essential to courtship and agonistic behaviours in many vertebrates. The swimbladder and associated muscles in batrachoidid fishes (midshipman and toadfish) is a unique vertebrate sound production system, wherein fundamental frequencies are determined directly by the firing rate of...

In the underwater environment, sound propagates both as a pressure wave and particle motion, with particle motions dominating close to the source. At the receptor level, the fish ear and the neuromast hair cells act as displacement detectors, and both are potentially stimulated by the particle motion component of sound. The encoding of the anterior...

Male oyster toadfish, Opsanus tau, produce long duration (250 to 650 msec duration) sexual advertisement calls or "boatwhistles" during the breeding season. When males are in close proximity, the fishes alternate the production of boatwhistles with other males to avoid call overlap. However, males can also produce a number of different sounds, incl...

Classical acoustic conditioning was investigated with the common carp (Cyprinus carpio) to determine its potential as a management tool for this invasive species. Groups of five juvenile carp were trained to associate a 400 Hz pure tone stimulus with a food reward in small laboratory tanks (≤ 1000 L). Following three days of training, the majority...

Reaction distances under various light intensities (0-19 uE/m2/s), angles of attack, swimming speeds, and percentage of overall foraging success were measured. Extensive efforts have been invested in restoring lean lake trout (Salvelinus namaycush) populations in the Laurentian Great Lakes, but successful natural recruitment of lake trout continues...

Monthly, overwinter and annual instantaneous growth rates for round goby Neogobius melanostomus were calculated with maximal growth occurring in July and August and almost no growth observed between ice appearance (October) and melt (March). Annual absolute growth rates averaged 27·3 ± 1·9 mm for males and 19·8 ± 2·4 mm for females. The most parsim...

The oyster toadfish, Opsanus tau, has been an important model organism for biomedical studies on muscle and sensory physiology. However, the function of large, fleshy multilobed protuberances called cirri that project from the head and jaw of the fish remains unknown. Additionally, the role of more simplified protuberances termed papillae that proj...

Title: Potential bioacoustic control for the round goby, Neogobius melanostomus Format: Poster Authors: Cordo, Elise B. University of Minnesota- Duluth Biology Dept; 218-726-6125; cord0128@d.umn.edu and Mensinger, Allen F. University of Minnesota- Duluth Biology Dept; 218-726-7259; amensing@d.umn.edu Presenter: Elise Cordo The round goby (Ne...

The round goby is an aggressive benthic fish native to the Ponto-Caspian region of Eurasia and has become invasive in the Laurentian Great Lakes. Competition for food and habitat are hypothesized to lead to the competitive exclusion of native species. We sought to determine the extent of interspecific competition between the round goby and the logp...

Abstract –  Despite its small size [adult: 60–130 mm, total length (TL)] and limited home range, the round goby (Neogobius melanostomus) has quickly become established throughout the Laurentian Great Lakes. Little information is available, however, on the natural dispersal pattern of this species. This capture–mark–recapture study utilised alphanum...

Marine teleost fish comprise one of the most diverse groups of luminescent animals with over 45 families and more than 190 genera containing luminescent species. Predominantly blue light is emitted diffusely through translucent tissue that harbors symbiotic bioluminescent bacteria, or discretely from complex photophores equipped with reflectors, le...

Acoustic advertisement signals have evolved in many taxa and are best known among arthropods, anurans, and birds. In populations where individuals alternate signals, males often adjust the timing of calls to avoid overlap. However, specific attempts at jamming especially using a signal that differs temporally and spectrally in fundamental frequency...

The invasive round goby Apollonia melanostomus (formerly Neogobius melanostomus) has negatively affected benthic fish communities throughout the Great Lakes. In this study, we compared the sensory physiology and behavior of three native species—slimy sculpin Cottus cognatus, spoonhead sculpin C. ricei, and logperch Percina caprodes—with those of th...

Male toadfish acoustically attract females to nesting sites by producing boat-whistle calls. To determine how the fish localize sound underwater, inductive neural telemetry was used to record from microwire electrodes chronically implanted into the utricular nerve of the toadfish, Opsanus tau. The telemetry tag allowed both laboratory and field mon...

Acoustic communication is critical for reproductive success in the oyster toadfish Opsanus tau. While previous studies have examined the acoustic characteristics, behavioral context, geographical variation, and seasonality of advertisement boatwhistle sound production, there is limited information on the grunt or other non-advertisement vocalizatio...

Sex steroid hormones are important for reproduction in all vertebrates, but few studies examine inter-individual, temporal, and population-level variations, as well as environmental influences on circulating steroid levels within the same species. In this study we analyzed plasma 11-ketotoestosterone (11-KT) and 17beta-estradiol (E(2)) levels in th...

Round gobies were first discovered in the Duluth-Superior Harbor, Lake Superior, in 1995. Anecdotal sightings by anglers and others suggested that the infestation was growing and expanding; however, direct evidence of the distribution and expansion rate in the harbor was largely unknown. Distribution and range of the round goby, Apollonia melanosto...

Regeneration of the teleost retina following surgical extirpation of 25% to 100% of the neural retina was investigated in goldfish (Carrasius auratus) and sunfish (Lepomis cyanellus). The retina will regenerate following removal of up to 95% of the neural retina, however complete extirpation prevented regeneration. Visual sensitivity was assessed b...

Simple (dorsal light reflex) and complex (predator-prey interactions) visually mediated behaviors were used concurrently with morphological examination to assess restoration of visual function following optic nerve crush in bluegill (Lepomis macrochirus) x pumpkinseed (Lepomis gibbosus) hybrid sunfish. Regenerating optic nerve axons projected into...

The effects of temperature and diet on the growth of captive year 0 specimens of Opansus tau were examined for two consecutive year classes. The 2001 year class was raised at about 23, 26, or 29 degrees C and provided with live brine shrimp, frozen butterfish and squid, or commercial food pellets (45% protein, 19% fat, and 3% fiber) three times per...

Inductive neural telemetry was used to record from microwire electrodes chronically implanted into the anterior lateral line nerve of the oyster toadfish, Opsanus tau (L.). The lateral lines of free-ranging toadfish were stimulated by the swimming movements of a prey fish (Fundulus heteroclitus), and the corresponding neural activity was quantified...

Blood biochemistry parameters were ex- amined in the oyster toadfishOpsanus tau from the late spring through early fall for two consecutive seasons to establish baseline values and evaluate whether any of the parameters could be used as predictors of disease and mortality in this important experimental organism. The blood plasma was analyzed for al...

Inductive neural telemetry was used to record from microwire electrodes chronically implanted into the anterior lateral line nerve of the toadfish, Opsanus tau. Spontaneous neural activity and the response of lateral line fibers to water current were continually monitored from 17 primary afferent fibers before, during, and after the administration...

The ability of age-0 year yellow perch Perca flavescans to detect prey using visual and mechano-sensory input was examined during laboratory feeding trials at varying light intensities. Perch were highly effective predators and captured Daphnia pulicaria with 94% overall foraging success at light levels ranging from 0 to 3400 lx. Maximum average re...

Nests of oyster toadfish Opsanus tau with guardian males were transported from Waquoit Bay, Massachusetts, to the Marine Biological Laboratory in Woods Hole, Massachusetts. Following larval detachment from the nest, the offspring were separated from the males and placed into culture tanks with flow-through seawater. The juveniles were initially fed...

The gravity sensors in the inner ear (the utricle and saccule) no longer receive strong gravitational signals in weightlessness. In an effort to compensate for the reduced input, these sensors may become more sensitive using a process called up-regulation. If this happens, the output of the vestibular nerve from the inner ear would be greatly incre...

One of the major goals of the Decade of the Brain (the 1990's) was the implementation of chronic interfaces to the nervous system. Such interfaces could serve as conduits for signal transmission past injured nerves or be used to control prostheses. One approach to this interface has been the sieve electrode. In this design, a small piece of silicon...

Vertebrates possess hair cell otolith organs of the inner ear, the utricule and saccule, that transduce inertial force due to head translation and head tilt relative to gravitational vertical, and transform the vector sum of the imposing accelerations into a neural code carried by the afferent nerve fibers. This code is combined in the central vest...

The consequence of exposure to microgravity on the otolith organs was studied by recording the responses of vestibular nerve afferents supplying the utricular otolith organ to inertial accelerations in four toadfish, Opsanus tau, sequentially for 5 days following two National Aeronautics and Space Administration shuttle orbital flights. Within the...