Meeting Abstract

P3.92  Jan. 6  Two sides to sound production: behavior and pulse patterns in spiny lobsters SHIPP, L. E.*; PATEK, S. N.; University of California, Berkeley; University of California, Berkeley leshipp@gmail.com

When interacting with predators, the California spiny lobster, Panulirus interruptus, generates pulsatile rasp sounds using a stick and slip friction mechanism. Sounds are produced by two independently controlled plectrum/file units at the base of each antenna. Because these sound producing apparatuses are activated independently, spiny lobsters have the ability to produce sounds using one side only, two sides sequentially or two sides simultaneously. Using audio and video recordings, we measured the signal features and behaviors associated with sound production. We found that sound production is correlated with two motor behaviors associated with escape attempts: leg movement and tail flip. In addition, tail flipping is correlated with presence of sequential or simultaneous sound production, but not with single side sound production. Furthermore, regardless of whether the lobsters use one or both sides, a greater number of sounds are produced per unit time during leg movement than when the legs are still. The behavioral option to use one or both plectrums allows for greater variation in rasp duration and pulse rate. Rasps consisted of one pulse to 30 pulses with durations of less than a millisecond to 0.45 seconds. Pulses were generated in both uniform and varied temporal intervals at rates between 8 and 192 pulses per second. The pulse rate did not correlate significantly with rasp duration, though there was a positive relationship between pulse number and rasp duration. By sequentially activating both plectrums to overlap two independent series of pulses, the animal is able to fit more pulses into a rasp, possibly to produce a more effective noise.