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 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.