A method and an apparatus for perfusion imaging using coded excitation. Each backsheet strip may include a water-impermeable layer and may be extensible. The liquid in the primary barrier is pressurized to a level substantially greater than the pressure of the surrounding water, and such pressure may be maintained or varied during the period of deployment of the breakwater. The outflow attracts insects to the vicinity of the device, and the inflow urges the insects to enter the device. The tacky adhesive, in turn, may be treated with a miticide or activated carbon.