Marine Mammals and Mapping

I’ve just returned from a symposium on “Cetaceans and Noise Mapping” sponsored by NOAA and agency partners Bureau of Ocean Energy Management (BOEM) and the Office of Naval Research (ONR).

The purpose of the meeting was to explore and expand on the idea of creating digital maps of our outer continental shelf fully embellished with sound propagation characteristics and populated with typical marine mammals found in the areas represented on the maps. The objective of these maps would be to inform policies on ocean use, determining areas that need particular types of protection, and identifying the conditions that would be permitted while exploiting other areas.

Bering Sea Map of Humpbacks (NOAA)

Bering Sea Map of Humpbacks (NOAA)

Bearing Sea Map of Humpbacks (NOAA)In using the system a proposed project such as a seismic survey or a military exercise could be modeled on the maps to see the impacts of introduced noise sources on the inhabitants of the area in question.

The project is really ambitious, particularly in light of what we don’t know about the ocean. While the seafloor geography can be represented fairly accurately, and the noises from various sources can be brought into play with the seafloor and the ‘typical’ water conditions, sound propagation is greatly influenced by sea states and seasonal thermal settings that are much harder to model.

Additionally, while there are some areas that may yield to reasonably accurate marine mammal populations due to the presence of many observers throughout the year (such as ocean sanctuaries adjacent to metropolitan areas with year-around whale watching boats) other areas might only be “populated” by one observation throughout an entire year.

The risk in this is that the paucity of data in one area may be confused with the abundance of data in another – and what we don’t know could be overshadowed by the little we do. In this context it could take decades to fully populate the maps. In the meanwhile decisions need to be made on how we inform ocean stakeholders and properly mitigate for noise impacts where required.

Nonetheless it is a worthy project as it will at least serve as a banner to consolidate the work of many researchers and provide yet another reason to support their work. And in a fully embellished, open architecture version anyone (or anything) who has input on marine mammals, noise sources, or observations on ocean conditions could input data onto the map. This will help researchers, policymakers, and the public understand many things about our interactions with the ocean.

The risk, as with any “virtualized” environment is that users could easily mistake the map for the territory.