题名: |
Comparison of Harbor Porpoise (Phocoena phocoena) Echolocation Clicks Recorded Simultaneously on Two Passive Acoustic Monitoring Instruments |
作者: |
Jacobson, E. K.; Merkens, K. P. B.; Forney, K. A.; Barlow, J. |
关键词: |
Harbor porpoise##Echolocation clicks##Comparison##Phocoena phocoena##Recorded Simultaneously##Passive acoustic detection##Hydrophone recording##Ocean Instruments##Narrow-band, high-frequency (NBHF)## |
摘要: |
Passive acoustic surveys are a useful tool for long-term assessment of cetacean populations. However, the application of these methods requires that species of interest produce distinctive, well-characterized vocalizations. Several sympatric species of cetaceans produce narrow-band, high-frequency (NBHF) echolocation clicks which are difficult to distinguish. On the U.S. West Coast, Dall's porpoise (Phocoenoides dalli) and harbor porpoise (Phocoena phocoena) emit NBHF echolocation clicks and overlap in distribution. To determine whether different passive acoustic instruments could be used to monitor harbor porpoise, we recorded harbor porpoise echolocation clicks simultaneously on an autonomous hydrophone recording system (SoundTrap, Ocean Instruments New Zealand) and on a commonly used passive acoustic monitoring device (C-POD, Chelonia Ltd., UK) and investigated whether the number and peak frequency of recorded echolocation clicks were consistent between the two instruments. We found that the number of echolocation clicks recorded by the two instruments was highly correlated. However, the C-POD and SoundTrap measurements of the peak frequency of echolocation signals were not well-correlated. This suggests that while both instruments are capable of detecting harbor porpoise echolocation clicks, it may not be feasible to use C-PODs to discriminate harbor porpoise echolocation clicks in regions where multiple species with NBHF echolocation clicks are present. The use of calibrated hydrophones with full-bandwidth recording instruments may be required for this task. |
总页数: |
16 |
报告类型: |
科技报告 |