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  • ECHO Program

    Study Summary

    February 2019 | Page 1 of 2

    W hale w atching boats and sm all vessel underw ater noise

    m easurem ents study

    Southern resident killer whales frequent Haro St rait during the sum m er m onths to feed.

    This area support s an act ive com m unity of recreat ional boaters and whale watching

    organizat ions, as well as internat ional shipping routes. Underwater noise from ships

    increases am bient noise levels and can interfere with the abilit y of whales to feed and

    com m unicate.

    To invest igate the underwater noise levels of whale watching boats and other sm all vessels

    that operate in the Salish Sea near southern resident killer whales (SRKW) sum m er feeding

    habitat , the Enhancing Cetacean Habitat and Observat ion (ECHO) Program and Fisheries

    and Oceans Canada supported a sm all vessel underwater noise m easurem ent study in Haro

    St rait . I n parallel with another study m easuring underwater noise levels from large piloted

    com m ercial ships in Haro St rait , this study was undertaken to bet ter understand the

    underwater noise em issions from sm all boats and vessels.

    This sum m ary docum ent describes how and why the proj ect was conducted, and it s key

    findings and conclusions.

    W hat quest ions w as the study t rying to answ er?

    The study aim ed to establish high-qualit y noise level m easurem ents for whale watching

    boats and sm all vessels, and evaluate the relat ionship between speed and sound levels from

    the boats, especially at higher frequencies relevant to SRKW com m unicat ion (500 to 15,000

    Hz) and echolocat ion (above 15,000 Hz) .

    W ho conducted the project?

    JASCO Applied Sciences (Canada) Ltd. was retained by the

    Vancouver Fraser Port Authority and Fisheries and Oceans

    Canada to conduct the study, using the listening stat ions

    deployed in Haro St rait as part of the larger 2017

    voluntary vessel slowdown t r ial.

    W hat m ethods w ere used?

    The ECHO Program sponsored the deploym ent of two

    underwater listening stat ions in Haro St rait from July to

    October 2017 to m easure sound levels produced m ainly by

    com m ercial ships t ransit ing the st rait .

    Several whale watching boats and other sm all vessels

    volunteered to perform t ransits past the two underwater listening stat ions. The study

    included 20 boats and sm all vessels, of which eleven were whale watching boats. Passes

    were recorded from six different vessel types including: four r idged-hull inflatable boats

    (RHI Bs) , ten m onohulls, two catam arans, two sailboats, a landing craft and a sm all boat

    with a 9.9 HP outboard engine. Part icipat ing boats perform ed at least two t ransits past one

    of the underwater listening stat ions at each of t he predeterm ined speeds: 5 knots, 9 knots

    and cruising speed.

    The underwater listening

    stat ion in Haro Strait captured

    noise levels of vessels t ransit ing the area.

  • VANCOUVER FRASER PORT AUTHORITY | ECHO Program Study Sum m ary

    This report is provided for interest only. I t s contents are solely owned by the Vancouver Fraser Port Author ity ECHO Program.

    Vancouver Fraser Port Author it y is not liable for any errors or om issions contained in this report nor any claim s ar ising from the use

    of informat ion contained therein.

    The listening stat ions were set t o m easure acoust ic data cont inuously, and were set to

    m easure at a higher sam ple rate in the early m orning hours to capture the higher frequency

    sound from whale watching boats and sm all vessels for the purpose of this study. Acoust ic

    data were analyzed using the ShipSound m odule of JASCO Applied Science’s PortListen®

    underwater noise m easurem ent software system . This software autom at ically calculates

    sound levels from boats using calibrated hydrophone data and accurate boat and vessel

    posit ion data according to the ANSI S12.64-2009 standard for ship noise m easurem ents.

    W hat w ere the key findings?

    Noise levels from several whale watching boats and other sm all vessels were m easured

    while t ransit ing at m ult iple speeds past two underwater listening stat ions deployed in Haro

    St rait .

    Key findings include:

    • I n general, noise levels from the boats and sm all vessels increased with speed for the sm all boats included in this study; however, the t rends are not as st rong as those of

    large com m ercial ships.

    • At slow speeds, less than seven knots, m edian noise levels from the boats and sm all vessels in the SRKW com m unicat ion band ranged from approxim ately 149 to 161 dB ( re

    1 μPa2 @ 1m ) ; and in the SRKW echolocat ion band ranged from approxim ately 133 to 169 dB (re 1 μPa2 @ 1m).

    • At fast speeds, greater t han 15 knots, m edian noise levels from the boats and sm all vessels in the SRKW com m unicat ion band were within 168 to 170 dB (re 1 μPa2 @ 1m); and in the SRKW echolocat ion band ranged from approxim ately 155 to 162 dB ( re 1

    μPa2 @ 1m). • The overall findings indicate a significant reduct ion in noise levels when boats are

    conduct ing whale-watching act ivit ies at slow speeds, less than seven knots, com pared to

    fast t ransit speeds of greater than 15 knots.

    • As with the larger com m ercial ships, there was a st ronger speed-sound correlat ion in the SRKW echolocat ion band than in lower- frequency bands, which is likely due to the

    greater im portance of propeller cavitat ion noise relat ive to engine noise.

    • Based on the lim ited num ber of boats and sm all vessels included in the study, correlat ions were largely conducted on the m onohull boat type, which had the largest

    sam ple size of t en unique boats. For these m onohull boats, speed through water had the

    st rongest correlat ion with noise level from the boat , followed by propeller type and

    vessel breadth in the SRKW com m unicat ion frequency range. Speed had the st rongest

    correlat ion in the SRKW echolocat ion range, followed total horsepower and vessel

    breadth.

    • Onboard echosounders produced a significant peak at approxim ately 50 kHz for som e vessels, which is within the m ost sensit ive hearing range of SRKW. I t is recom m ended

    that vessels turn off their echosounders when in proxim ity to high- frequency hearing

    m arine m am m als.

    Conclusions

    This project was inst rum ental in advancing the understanding of noise levels from whale

    watching boats and sm all vessels t ransit ing in SRKW crit ical habitat , and how they vary with

    speed. Although this is one of the m ost com prehensive sm all vessel noise em ission studies

    to date, it should be noted that the findings are based on a relat ively sm all sam ple size per

    vessel type.

  • Version 3.0 i

    Whale Watch and Small Vessel Underwater Noise Measurements Study

    Final Report

    Submitted to:

    Rangyn Lim

    Krista Trounce Vancouver Fraser Port Authority ECHO Program Contract: 17-0070

    Authors:

    Jennifer Wladichuk David Hannay Alexander MacGillivray Zizheng Li

    30 April 2018

    P001368-002 Document 01522 Version 3.0

    JASCO Applied Sciences (Canada) Ltd Suite 2305, 4464 Markham St. Victoria, BC V8Z 7X8 Canada

    Tel: +1-250-483-3300 Fax: +1-250-483-3301

    www.jasco.com

    http://www.jasco.com/

  • Version 3.0 i

    Suggested citation:

    Wladichuk, J., D. Hannay, A. MacGillivray, Z. Li. 2018. Whale Watch and Small Vessel Underwater Noise Measurements Study: Final Report. Document 01522, Version 3.0. Technical report by JASCO Applied Sciences for Vancouver Fraser Port Authority ECHO Program.

    Disclaimer:

    The results presented herein are relevant within the specific context described in this report. They could be misinterpreted if not considered in the light of all the information contained in this report. Accordingly, if information from this report is used in documents released to the public or to regulatory bodies, such documents must clearly cite the original report, which shall be made readily available to the recipients in integral and unedited form.

  • JASCO APPLIED SCIENCES Whale Watch and Small Vessel Underwater Noise Measurements Study

    Version 3.0 ii

    Contents

    EXECUTIVE SUMMARY ........................................................................................................ 1

    1. INTRODUCTION .............................................................................................................. 3

    2. METHODS ...................................................................................................................... 4

    2.1. Whale Watch and Small Vessel Acoustic Emissions Study Overview ............................................. 4

    2.2. Underwater Listening Stations .......................................................................................................... 6

    2.3. ShipSound Analysis ..............................................................................................................

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