| shifts in frequency-modulated pulses recorded during an encounter with blainville's beaked whales (mesoplodon densirostris). | echolocation signals produced by beaked whales (family: ziphiidae) include frequency-modulated (fm) pulses that appear to have species-specific characteristics. to date there has been no established evidence that a single species of beaked whale might produce more than one type of fm pulse. in 2014 a group of blainville's beaked whales (mesoplodon densirostris) were sighted off of southern california; recordings included fm pulses with significant increases in peak frequency, center frequency, a ... | 2016 | 27586775 |