344
frequency occurred in Pipa (0.78 kHz), with a minimum number of harmonics
higher than other regions (3 harmonics).
The sounds produced by boats (diesel and petrol) in the three regions were synthesized in order to obtain a range of values (frequencies) for comparison of these
impacts. The minimum and maximum values of frequencies (kHz) of all recorded
anthropic activities are presented in the Table 13.4.
A water pump in Pipa beach used to be turned on every day in the late afternoon
to fill up a swimming pool of a resort, creating noise from 1.84 to 8.14 kHz.
Regarding to the frequency range, small petrol engine boats (Fig. 13.18) emitted
the highest frequencies, reaching 46.8 kHz, followed by diesel engine boats (35.71
kHz) (Fig. 13.19) while other noise sources had significantly lower maximum frequencies 20 kHz (wood-barges) (Fig. 13.20), 17.30 kHz (dredging) (Fig. 13.21) and
8.14 kHz (water pump).
Table 13.2 Values of minimum, maximum, initial, final and delta frequencies and duration of the
whistles from Sotalia guianensis populations from Cananéia estuary (CAN), Caravelas estuary
(CVL) and Pipa beach (PIP)
Whistles
Min.
Freq.
(kHz)
Max.
Freq.
(kHz)
Initial
Freq.
(kHz)
Final
Freq.
(kHz)
Delta
Freq.
Duration (s)
CAN Min.-Max. 4.6–12.4
8.5–19.9
4.7–12.6 8.5–19.9
Ø – 15.2 0.038–0.476
Mean
8.2
16.4
8.5
16.3
–
0.231
CVL Min.-Max. 2.5–14.3
10.4–24.0 3.7–23.3 2.5–24.0
0.6–18.4 0.032–0.564
Mean
10.1
17.2
10.1
16.8
7.1
0.265
PIP
Min.-Max. 5.6–11.9
10.5–18.4 5.6–15.6 10.5–18.4 Ø – 12.8 0.056–0.680
Mean
8.6
15.7
9.7
16.4
–
0.315
Table 13.3 Values of minimum, maximum and mean frequencies, mean duration and minimum
and maximum number of harmonics of the pulsed calls from Sotalia guianensis populations from
Cananéia estuary (CAN), Caravelas estuary (CVL) and Pipa beach (PIP)
Pulsed
Calls
Min. Freq.
(kHz)
Max. Freq.
(kHz)
Mean
(kHz)
Mean duration (s)
Min.- Max.
Harmonics
CAN
0.42
5.00
3.00
0.1–2.1
1–15
CVL
0.18
24.00
6.65
0.12
1–38
PIP
0.78
17.20
0.98
0.20
3–24
Table 13.4 Values of minimum and maximum frequencies of the anthropogenic noises in
Cananéia estuary (CAN), Caravelas estuary (CVL) and Pipa beach (PIP)
Source
Min. Freq. (kHz)
Max. Freq. (kHz)
Diesel engine boats (CAN; CVL; PIP)
0.38
35.71
Petrol engine boats (CAN; CVL; PIP)
0.84
46.80
Wood-barges (CVL)
0.02
20.00
Dredging activity (CVL)
0.15
17.30
Water Pump (PIP)
1.84
8.14
F. de Sousa Pais et al.
frequency occurred in Pipa (0.78 kHz), with a minimum number of harmonics
higher than other regions (3 harmonics).
The sounds produced by boats (diesel and petrol) in the three regions were synthesized in order to obtain a range of values (frequencies) for comparison of these
impacts. The minimum and maximum values of frequencies (kHz) of all recorded
anthropic activities are presented in the Table 13.4.
A water pump in Pipa beach used to be turned on every day in the late afternoon
to fill up a swimming pool of a resort, creating noise from 1.84 to 8.14 kHz.
Regarding to the frequency range, small petrol engine boats (Fig. 13.18) emitted
the highest frequencies, reaching 46.8 kHz, followed by diesel engine boats (35.71
kHz) (Fig. 13.19) while other noise sources had significantly lower maximum frequencies 20 kHz (wood-barges) (Fig. 13.20), 17.30 kHz (dredging) (Fig. 13.21) and
8.14 kHz (water pump).
Table 13.2 Values of minimum, maximum, initial, final and delta frequencies and duration of the
whistles from Sotalia guianensis populations from Cananéia estuary (CAN), Caravelas estuary
(CVL) and Pipa beach (PIP)
Whistles
Min.
Freq.
(kHz)
Max.
Freq.
(kHz)
Initial
Freq.
(kHz)
Final
Freq.
(kHz)
Delta
Freq.
Duration (s)
CAN Min.-Max. 4.6–12.4
8.5–19.9
4.7–12.6 8.5–19.9
Ø – 15.2 0.038–0.476
Mean
8.2
16.4
8.5
16.3
–
0.231
CVL Min.-Max. 2.5–14.3
10.4–24.0 3.7–23.3 2.5–24.0
0.6–18.4 0.032–0.564
Mean
10.1
17.2
10.1
16.8
7.1
0.265
PIP
Min.-Max. 5.6–11.9
10.5–18.4 5.6–15.6 10.5–18.4 Ø – 12.8 0.056–0.680
Mean
8.6
15.7
9.7
16.4
–
0.315
Table 13.3 Values of minimum, maximum and mean frequencies, mean duration and minimum
and maximum number of harmonics of the pulsed calls from Sotalia guianensis populations from
Cananéia estuary (CAN), Caravelas estuary (CVL) and Pipa beach (PIP)
Pulsed
Calls
Min. Freq.
(kHz)
Max. Freq.
(kHz)
Mean
(kHz)
Mean duration (s)
Min.- Max.
Harmonics
CAN
0.42
5.00
3.00
0.1–2.1
1–15
CVL
0.18
24.00
6.65
0.12
1–38
PIP
0.78
17.20
0.98
0.20
3–24
Table 13.4 Values of minimum and maximum frequencies of the anthropogenic noises in
Cananéia estuary (CAN), Caravelas estuary (CVL) and Pipa beach (PIP)
Source
Min. Freq. (kHz)
Max. Freq. (kHz)
Diesel engine boats (CAN; CVL; PIP)
0.38
35.71
Petrol engine boats (CAN; CVL; PIP)
0.84
46.80
Wood-barges (CVL)
0.02
20.00
Dredging activity (CVL)
0.15
17.30
Water Pump (PIP)
1.84
8.14
F. de Sousa Pais et al.