Browsing by Subject "bigheaded carp"
Now showing 1 - 3 of 3
Results Per Page
Sort Options
Item Acoustic and chemical conditioning and retention for behavioral deterrence in invasive bigheaded carps (Hypophthalmichthys molitrix and H. nobilis)(2023-05) Culotta, JackieInvasive bigheaded carps (Hypophthalmichthys molitrix and H. nobilis) are two aquatic invasive species that are expanding their range throughout the Mississippi River Basin. These carp display negative phonotaxis to broadband sound and thus acoustic deterrents have shown promise for managing their populations. Numerous dams block direct upstream access for the carp; however, fish can bypass these physical obstructions by swimming though navigational locks. Nonphysical acoustic deterrents have the advantage of not effecting navigation, are relatively inexpensive, and could be tuned above the hearing range of non-ostariophysian fishes. Fish also react negatively to high levels of carbon dioxide, and it has been proposed to combine these two stimuli into one deterrent system to reduce potential habituation to long term acoustic playbacks and increase barrier efficacy. Here, the possible synergies of combining these two stimuli into integrated deterrent systems are evaluated.Item Data for Evaluation of a broadband sound projected from the gates of a navigation lock in the Mississippi River shows it to be a weak deterrent for common carp and unable to block passage(2022-01-19) Riesgraf, Andrew T.; Finger, Jean S.; Zielinski, Daniel P.; Dennis III, Clark E.; Whitty, Jeff M.; Sorensen, Peter W.; soren003@umn.edu; Sorensen, Peter W.; University of Minnesota - Minnesota Aquatic Invasive Species Research CenterThere is an urgent need to block the passage of carp and other invasive fishes through navigational locks in large rivers. Although the broadband sound of an outboard motor has been shown to strongly repel three species of carp in laboratory flumes and to a lesser extent inside of a lock chamber, it has not yet been tested to see if it can stop carp from entering a lock. To test this possibility, we attached speakers to lock gates and played the sound of an outboard motor while measuring its efficacy by tracking free-ranging transplanted tagged common carp in its vicinity. Eight groups of 20 carp were tested while the sound system was turned on and off for 2 week periods. When the sound system was on, these carp spent approximately one-third less time in front of the gates than when it was off which when modeled by GLMM was shown to no greater than the effects of river discharge or temperature. Further, there was no indication that this sound blocked carp from entering and presumably passing through the lock. However, the number of times that tagged carp entered the lock was low even when the sound was off. A number of factors may have contributed to the limited efficacy of this deterrent system including the sound itself.Item Evaluating the ability of sound, an air curtain, and high-intensity light, both alone and together, to deter bighead and common carps(2019-12) Dennis, ClarkThere is an urgent need to develop deterrent systems to impede the spread of invasive silver carp (Hypophthalmichthys molitrix), bighead carp (H. nobilis) and common carp (Cyprinus carpio). Sound, light and air curtains have all been shown to deter carp; however, no study to date had systematically compared the responses of carp to each of these deterrents. The overarching goal of this dissertation was to determine whether and how sound, light and air might be used, either on their own or together, to impede the movement of invasive carps while having minimal effects on other fishes. Four laboratory and one field study were conducted. When tested in a dimly-lit laboratory flume, bighead and common carps were more deterred by a 20-2000 Hz cyclic sound than a broad-spectrum outboard-motor sound (10-10,000 Hz) (p < 0.05). Further, coupling these sounds with an air curtain enhanced their ability to block fish passage in the laboratory (> 97% blocked by the coupled cyclic sound and air curtain). A second laboratory experiment showed that lake sturgeon (Acipenser fulvescens) and brown trout (Salmo trutta) were less deterred by the broad-spectrum outboard-motor sound than either bighead or common carps. However, none of these fishes were deterred by this sound when frequencies lower than 1000 Hz were removed. Another laboratory experiment showed that constantly-lit and strobing lights blocked 80% of bighead carp in a dimly-lit flume, while a constant light worked better than a strobing light in a well-lit background (80% and 33% blocked, respectively) (p < 0.05). Largemouth bass were similarly repelled by light in a dimly-lit flume, but attracted to the light in a well-lit environment. The last laboratory experiment examined the response of bighead carp to different combinations of light, sound and air curtains. Greater than 90% blockage for carp was observed when strobing light (but not constant light) was combined with sound and/or an air curtain. A final field study, conducted in a lock chamber, found that although adult common carp were initially deterred by the outboard-motor sound in the lock, they habituated after single exposure; whereas in the laboratory, habituation occurred only after three exposures. Several factors, including differences between sound fields observed in the laboratory and field, may have been responsible. Together, these experiments suggest broad-spectrum sounds are well suited to block carp, especially if they are coupled with an air curtain and strobing light. Field tests are needed to fully evaluate their potential.