GAS AND BUBBLE PRODUCTION BY SIPHONOPHORES.

Gas-filled siphonophore floats collected from a deep scattering layer DSL were photographed in the act of voluntarily expelling bubbles of nearly pure carbon monoxide. These observations suggest the possible release of free bubbles in the sea at depths considerably greater than previously known. Such free bubbles, together with the siphonophore floats themselves, constitute a biological family of potentially resonant sonar targets. Measurements of rates of gas production and diffusion, and of bubble and float dimensions, indicate the possibility of acoustic targets within the DSL which will resonate in response to sonar frequencies of less than 10 to greater than 110 kcs depending upon depth. Author