Data from: Low frequency sampling rates are effective to record bottlenose dolphins
Acoustic monitoring in cetacean studies is an effective but expensive approach. This is partly because of the high sampling rate required by acoustic devices when recording high-frequency echolocation clicks. However, the proportion of recording echolocation clicks at different frequencies is unknow...
Main Authors: | , , , , , |
---|---|
Format: | Software |
Language: | unknown |
Published: |
2021
|
Subjects: | |
Online Access: | https://zenodo.org/record/5137898 https://doi.org/10.5281/zenodo.5137898 |
Summary: | Acoustic monitoring in cetacean studies is an effective but expensive approach. This is partly because of the high sampling rate required by acoustic devices when recording high-frequency echolocation clicks. However, the proportion of recording echolocation clicks at different frequencies is unknown for many species, including bottlenose dolphins. Here, we investigated the echolocation clicks for two subspecies of bottlenose dolphins in the western South Atlantic Ocean. The possibility of record echolocation clicks at 24 and 48 kHz was assessed by two approaches. First, we considered the clicks in the frequency range up to 96 kHz. We found a loss of 0.95-13.90% of echolocation clicks in the frequency range below 24 kHz, and 0.01-0.42% below 48 kHz, to each subspecies. Then, we evaluated these recordings downsampled at 48 and 96 kHz and confirmed that echolocation clicks are recorded at these lower frequencies, with some loss. Therefore, despite reaching high frequencies, the clicks can also be recorded at lower frequencies because echolocation clicks from bottlenose dolphins are broadband. We concluded that ecological studies based on presence-absence data are still effective for bottlenose dolphins when acoustic devices with a limited sampling rate are used. 01_data_prop_freq.csv The file contains 220 one minute samples (rows) and seven columns: dolphin_group contains a string for each group recorded, with a prefix for coastal (COAST) and offshore (OFF) recordings, and the ID of the group separated by an underline; environment contains information of the environment where the recording was made (coastal or offshore); recording contains the number of the recording file; duration contains the sample duration in seconds (up to 60 s); click_L24 contains the number of clicks only detected in frequencies below 24 kHz; clicks_L48 contains the number of clicks detected in frequencies up to 48 kHz; clicks_total contains all the clicks detected up to 96 kHz. Data_GPS_location.csv The file contains 18 locations of ... |
---|