Carp have escaped from fish farms and threaten fresh water ecologies. The rapidly growing and reproducing fish are pushing out native species in the Mississippi and Missouri rivers and are threatening the Great Lakes. Traditional methods have failed to hold the expansion of carp populations.
Fish can be detected using sonar finders but are still harvesting using traditional nets and fishing lines. Carp can escape these snares and quickly repopulate an area.
The proposed design would enable the suppression of carp populations.
Sonic guns, developed as anti-swimmer defenses, could be employed to stun fish. Underwater acoustic systems introduced for diver deterrent generate low frequency sound s that interferes with breathing, induces vestibular disorientation, panic, and uncontrolled ascent to surface. This systems could be employed against carp.
The proposed design uses Time Reversal Acoustic (TRA) as shown in the attached figure to precisely target carp with intense focused sound. An array of emitter-detectors initially transmit a low-powered sonic pulse. It may be possible based on the signal return to separate native fish from the invading carp; the system could, in more than one sense. be focused on carp.
The echo from the carp is "time reversed", amplified and focused back to the carp in real-time. The tightly controlled beam should stun the carp sending it floating to the surface without affecting nearby fish.
Even if a native fish is caught in the same beam as the carp the two can be separated at the surface and the native fish returned to the river.
Stevens Institute of Technology has demonstrated a TRA anti-diver system that can control a sonic beam up to 700 meters distant from the source. Carp should require less power to be stunned than a human diver.
The system would have to be demonstrated in a river system but no significant hurdles exist to the rapid demonstration and, if successful, deployment against this threat to native fish populations.