Most Croakers are gregarious, community animals and make noise by way of oscillating their swim bladder as part of their spawning ritual. The swim bladder is a pocket of air inside most fish that helps keep them afloat and facing upright. Male croakers use this sound to attract females. Being the first day of Spring I figured it was a good time to go give them a visit.
Recorded at low-tide on the bridge over the San Gabriel River that connects Seal Beach to Long Beach at Marina Drive. From this bridge it is less than 1 mile from the open ocean. The Croakers were very active, there is also shrimp and even frogs if you listen close enough. There was also a fair amount of car traffic (vibrating the bridge and being picked up) and some small boat noise in the distance.
Recorded on a Mix Pre 6 II with DIY OPA Hydrophones
Hydrophones Available
Hydrophone – 40ft
High-quality piezo cylinder and OPA-based impedance convertor encased in polyurethane
Specs:
Cable: Canare L-2T2S – 40ft
Connector: Neutrik NC3MXX XLR
Piezo: Steminc Cylinder
Circuit: OPA Alice mini
Required Power: 48v
Built to order – 30 day turnaround time
Built based on the fantastic Instructable and OPA Alice circuit designed by Jules Ryckebusch