|Title||Shifts in frequency-modulated pulses recorded during an encounter with Blainville's beaked whales (Mesoplodon densirostris)|
|Publication Type||Journal Article|
|Year of Publication||2016|
|Authors||Keating J.L, Barlow J, Rankin S.|
|Journal||Journal of the Acoustical Society of America|
|Type of Article||Article|
|Keywords||clicks; echolocation signals; prey; pseudorca-crassidens; transmission beam pattern|
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, and -10 dB bandwidth relative to FM pulses previously attributed to this species. This research suggests there may be greater variation in received beaked whale FM pulses than previously understood.