UC San Diego Library – Scripps Digital Collection

UCDWR No. U100. This investigation was undertaken to obtain information onthe northward extension of crackling underwater noises characteristicof the coastal waters of Southern California and for the purpose ofobserving if there were any seasonal changes in background noises inthe Puget Sound area which had been visited previously in November1942. The regions visited include Santa Barbar.a, San Luis Obispo,Monterey and Eureka to Crescent City in California, and AdmiraltyInlet and the San Juan Archipelago in Puget Sound.The characteristic crackling noises produced by snappingshrimps were found only at Santa Barbara, San Luis Obispo, andMonterey. In the northern California and Puget Sound areas wherethese animals have not been reported the waters were relatively freefrom biological noises, only very weak crackling and piping soundswere detected. There was no noticeable seasonal change .in noiseconditions in the Puget Sound area.