COP12 Resolution on Adverse Impacts of Anthropogenic Noise on Cetaceans and Other Migratory Species, incl. CMS Family Guidelines on Environmental Impact Assessments for Marine Noise-generating Activities

Several resolutions of ASCOBANS, ACCOBAMS and CMS have recognized underwater noise as a major threat to many marine species. These resolutions call for noise-related considerations to be taken into account as early as the planning stages of activities, especially by making effective use of Environmental Impact Assessments (EIA). Thanks to a voluntary contribution from Monaco, the CMS Secretariat on behalf also of the ACCOBAMS and ASCOBANS Secretariats was able to hire consultants to undertake this work.

Following a multi-step consultation process as outlined in UNEP/CMS/COP12/Doc.24.2.2, Resolution 12.14 on Adverse Impacts of Anthropogenic Noise on Cetaceans and Other Migratory Species was adopted by the 12th Meeting of the Conference of the Parties to CMS. In its Annex, it contains CMS Family Guidelines on Environmental Impact Assessments for Marine Noise-generating Activities.

These Guidelines cover the necessary detail for meaningful EIAs for Military and Civil High-powered Sonar, Shipping and Vessels Traffic, Seismic Surveys (Air Gun and Alternative Technologies), Construction Works, Offshore Platforms, Playback and Sound Exposure Experiments, Pingers (Acoustic Deterrent/Harassment Devices, Navigation), and other Noise-generating Activities (Acoustic Data Transmission, Wind, Tidal and Wave Turbines and Future Technologies).

The Resolution urges Parties to ensure that Environmental Impact Assessments take full account of the effects of activities on CMS-listed marine species and their prey and consider a more holistic ecological approach at a strategic planning stage. The Guidelines are designed to support them in this endeavour.


Technical Support Information

Parties and members of the advisory bodies and relevant working groups of CMS, ACCOBAMS and ASCOBANS were also invited to peer review the expert-authored Technical Support Information Modules made available below. Changes remained at the discretion of each author.

A single file containing all Modules of the Technical Support Information is available here and as UNEP/CMS/COP12/Inf.11.

COP13 (2020) in Decision 13.59 c) instructed the Secretariat to add the Advisory Note: Further guidance on independent, scientific modelling of noise propagation (UNEP/CMS/COP13/Inf.8) to the Technical Support Information.

Outline of Modules:

  • Executive Summary

  • Module A: Sound in Water is Complex’
    provides an insight into the characteristics of sound propagation and dispersal. This module is designed to provide decision-makers with necessary foundation knowledge to interpret the other modules in these guidelines and any impact assessments that are presented to them for consideration.

  • ‘Module B: Expert Advice on Specific Species Groups’
    presents twelve separate detailed sub-modules covering each of the CMS species groups, focusing on species' vulnerabilities, habitat considerations, impact of exposure levels and assessment criteria.
    B.1.     Inshore Odontocetes
    B.2.     Offshore Odontocetes
    B.3.     Beaked Whales
    B.4.     Mysticetes
    B.5.     Pinnipeds
    B.6.     Polar Bears
    B.7.     Sirenians
    B.8.     Marine and Sea Otters
    B.9.     Marine Turtles
    B.10.  Fin-Fish
    B.11.  Elasmobranchs
    B.12.  Marine Invertebrates

  • ‘Module C: Decompression Stress’
    provides important information on bubble formation in marine mammals, the source of decompression stress, the source frequency, level and duration, and assessment criteria.

  • ‘Module D: Exposure Levels’
    presents a summary of the current state of knowledge about general exposure levels.

  • ‘Module E: Marine Noise-generating Activities’
    provides a brief summary of military sonar, seismic surveys, civil high powered sonar, coastal and offshore construction works, offshore platforms, playback and sound exposure experiments, shipping and vessel traffic, pingers and other noise-generating activities. Each section presents current knowledge about sound intensity level, frequency range and the activities general characteristics. The information is summarized in a table within the module.

  • ‘Module F: Related Intergovernmental or Regional Economic Organization Decisions’
    presents the series of intergovernmental decisions that have determined the direction for regulation of anthropogenic marine noise.

  • ‘Module G: Principles of EIAs’
    establishes basic principles including strategic environmental assessments, transparency, natural justice, independent peer review, consultation and burden of proof.

  • ‘Module H: CMS-Listed Species Potentially Impacted by Anthropogenic Marine Noise’


The Government of the Principality of Monaco were recognized as Champion for their generous support and commitment towards marine species conservation for the period 2015 – 2017. The development of the guidelines has been funded with the contribution granted by Monaco under the Migratory Species Champion Programme.