Passive acoustic monitoring as a tool for offshore wind farm biodiversity assessments: a pilot study

Pilot study on the use of underwater passive acoustic recordings to monitor changes in biodiversity on the East Coast of Scotland. The focus of this study was to assess fish’s and crustacean’s active and passive sounds.


8. Supplementary materials

S1 Sound Pressure Levels

Sound Pressure Levels were calculated using PAMGuide in MATLAB (Merchant et al. 2015). Third-Octave Level (TOL) SPLs were calculated at 60-second resolution from 1-2000Hz, in order to characterise both benthic biodiversity and noise pollution from shipping noise (Merchant et al. 2016). TOL data was calculated based on the raw sound files. While some shipping activity is present at the St Abbs location (SPL peaks at 130 dB and 120 dB), the 10th of April is mostly absent of ship noise.

Daily average SPL data for the 100Hz third-octave level across all 8 moorings. April 10th is the best date for covering all sites, without high levels of shipping noise.
Daily average SPL data for the 100Hz third-octave level across all 8 moorings. April 10th is the best date for covering all sites, without high levels of shipping noise.
Hourly average SPL for 100Hz third-octave level on April 10th 2021.
Hourly average SPL for 100Hz third-octave level on April 10th 2021.

S2 Biological and environmental data sets

Overview of the contextual and environmental data layers, which were downloaded from open-source websites.

Layer

Source

Depth (m)

General Bathymetric Chart of the Oceans

Habitat map (EUNIS classification)

UK Sea Map 2018

Temperature, Currents, Light, DOC, Phytoplankton, Primary Productivity, Chlorophyll

Bio Oracle

Faunal cluster class, benthic biodiversity

OneBenthic Portal

NBN atlas

NBN atlas

Spawning and nursery ground layers

Spawning and Nursery Grounds Layers for Selected Fish in UK Waters in 2010 - Cefas

Developing essential fish habitat maps - Scottish Government 2023

S3 Start time and length of the recordings

The timings which are highlighted in bold indicate the files that had the largest amount of noise pollution and were therefore drastically reduced in file length.

Site

Phase

Start time

Cleaned file length (mm:ss)

Arbroath

Midnight

01:20:00

04:12

Arbroath

Sunrise

06:20:00

03:16

Arbroath

Midday

13:20:00

02:43

Arbroath

Sunset

19:50:00

04:02

CrudenBay

Midnight

01:25:00

09:50

CrudenBay

Sunrise

06:25:00

09:56

CrudenBay

Midday

12:55:00

09:46

CrudenBay

Sunset

19:55:00

09:40

Fraserburgh

Midnight

01:05:00

05:31

Fraserburgh

Sunrise

06:35:00

09:17

Fraserburgh

Midday

13:05:00

06:02

Fraserburgh

Sunset

20:05:00

09:40

Helmsdale

Midnight

01:25:00

09:59

Helmsdale

Sunrise

06:25:00

09:59

Helmsdale

Midday

13:25:00

09:59

Helmsdale

Sunset

19:55:00

09:59

Latheron

Midnight

01:15:00

06:27

Latheron

Sunrise

06:15:00

09:38

Latheron

Midday

13:15:00

04:29

Latheron

Sunset

19:45:00

06:50

SpeyBay

Midnight

01:15:00

09:58

SpeyBay

Sunrise

06:15:00

09:59

SpeyBay

Midday

13:15:00

09:40

SpeyBay

Sunset

19:45:00

10:00

StAbbs

Midnight

01:00:00

09:27

StAbbs

Sunrise

06:30:00

10:00

StAbbs

Midday

13:00:00

09:18

StAbbs

Sunset

20:00:00

09:09

StAndrews

Midnight

01:00:00

09:58

StAndrews

Sunrise

06:30:00

09:53

StAndrews

Midday

13:00:00

10:00

StAndrews

Sunset

20:00:00

09:52

S4 Biological variables associated with each site

Location

Predicted Habitat type

Depth (m)

Taxa Richness

Faunal Class

Area Class (km2)

No. Taxonomic Classes

Spey Bay

Coarse

23

8±5

D2c

136.66

5

Latheron

Coarse

26

24±8

D2a

30.69

3

Fraserburgh

Coarse

38

27±8

D2b

147.57

3

St Andrews

Coarse

41

27±8

D2b

152.59

6

St Abbs

Hard

34

8±5

D2c

17.86

5

Cruden Bay

Sandy

21

8±5

D2c

152.72

5

Arbroath

Sandy

47

24±8

D2b

65.13

5

Helmsdale

Sandy

48

24±8

D2b

295.15

5

S5 Summary data for the types of sounds used to calculate phonic richness

Presented are the mean duration, frequencies and power of each sound type.

Row Labels

Count of Sound Type

Average Duration (s)

Low frequency (Hz)

High frequency (Hz)

Peak frequency (Hz)

ST1

143

0.44

25.56

572.6

82.28

ST2

49

0.19

5682.49

26705

7875

ST3

22

0.35

193.75

1037.16

421.88

ST4

53

0.83

197.53

2610.7

397.11

ST5

4

0.2

145.84

745.78

410.16

ST6

931

0.3

260.8

2386.31

547.7

ST7

27

2.58

1786.84

12053.26

3168.4

ST8

3

0.67

1996.22

20478.08

2828.13

ST9

1

0.24

0

5714.31

46.88

ST10

3

0.44

2067.21

5885.98

3015.63

ST11

18

0.23

856.82

1956.79

1200.52

ST12

5

0.36

650.29

1978.17

937.5

ST13

18

0.25

32.04

642.29

85.94

ST14

2

0.27

0

2373.23

46.88

ST15

2

0.88

129.27

1246.28

164.06

ST16

15

0.78

40.22

1634.3

115.63

Contact

Email: ScotMER@gov.scot

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