In 2012 I moved to Rio de Janeiro to work as a Marine Mammal Observer. Despite my field research experiences with cetaceans, I had never worked with environmental licensing or environmental legislation until then. This was a bright new world.
Offshore, on board seismic vessels, my responsibilities included registering and monitoring the presence of cetaceans and marine turtles, and stopping seismic activities depending on the proximity of the animals to the vessel's airguns. For those unfamiliar with seismic activities at sea, here is how things work.
Seismic vessels at sea are mainly either searching for oil and gas under the bottom of the ocean, or assessing how much oil and gas is left in an existing reservoir. The latter type of survey is commonly known as a 4D seismic survey - the fourth dimension being time.
To be able to 'see through' the different layers of the ocean bottom, seismic vessels tow an array of air guns and cables containing hydrophones (which are basically underwater microphones). The airguns are fired roughly every ten seconds. The airguns shoot compressed air and make a really loud noise. The sound waves travel through the ocean, and reflect at different speeds, depending on the density of the layers that exist in the bottom. Those reflected waves are captured by the hydrophones and allow geologists and oceanographers to visualize what's underneath the ocean floor.
But there is one problem. The noise produced by the airguns affect marine life. The most obvious impacts are on cetaceans, who use sound to communicate, and may even go temporarily deaf due to the noise made by airguns. But seismic surveys are now known to affect other marine animals too, including fishes, and invertebrates such as cephalopods.
Brazilian legislation aims to protect cetaceans and marine turtles. It determines that whenever those animals are within 500 meters of the sound source (the airguns), seismic operations must be suspended. To ensure that these guidelines are followed, three Marine Mammal Observers are placed on every seismic vessel operating in Brazilian waters. Monitoring happens from sunrise to sunset, and in some operations, acoustic monitoring is also required overnight.
My experience as a Marine Mammal Observer brought much joy and also frustration to my still young conservation career. I was extremely frustrated by the way environmental licensing and monitoring happens in Brazil. Should the seismic companies hire their own licensing and monitoring crew? I was surprised by the high turnover of employees and the lack of qualification of many MMOs and Environmental Technicians brought on board. I was also appalled at how the fragility of working relationships offshore may impact the quality of environmental management. One of my motivations in returning to Brazil to work in marine conservation is to try and address some of these problems.
