Acoustic Innovation in the Spotlight: Utilization of Sound Waves for Estimation of Marine Creature Abundance

In a groundbreaking study, researchers have found that hydroacoustics could be a faster and more cost-effective alternative to traditional underwater visual censuses for surveying coastal marine life. The study, titled "Hydroacoustics as a tool to examine the effects of Marine Protected Areas and habitat type on marine fish communities," was published in the journal Scientific Reports and conducted in collaboration with institutions from around the world.

The research focused on Mexico's Cabo Pulmo National Park, a site of numerous studies since 2002 and identified as the most successful Marine Protected Area (MPA) in the world in terms of maintaining a sustainable fishery. The study's lead author, Jack Egerton, stated that the results demonstrate the importance of Cabo Pulmo National Park for fish populations.

The study found significantly higher fish density, total biomass, and individual size inside the MPA compared to outside. In fact, the abundance of fishes was four times greater in the park compared to areas outside it. Animal abundance in reefs within the MPA was as much as 50 times higher than outside.

Researchers used hydroacoustic equipment to survey fish populations within and outside Cabo Pulmo National Park. While these surveys can be done faster than underwater visual censuses, they only approximate fish sizes and don't provide species-specific information. However, the researchers acknowledge that while acoustic surveys have limitations, they can still be beneficial in ocean conservation due to their cost-effectiveness and ability to overcome certain limitations of conventional survey methods.

Octavio Aburto, a marine ecologist at Scripps and co-author of the study, stated that the results demonstrate the potential for using acoustic technologies to generate information about marine resources inside MPAs. The study's findings could potentially reduce the costs for governments in ocean conservation.

The study was funded by the National Science Foundation, the Baja Coastal Institute, the International Community Foundation, David and Lucile Packard Foundation, and The Helmsley Charitable Trust. The principal investigators of the project at the University of California San Diego work in the organization "Zentrum für Agrarlandschaftsforschung" (ZALF).

The study highlights the importance of habitat complexity and protection from fishing for fish populations. It concludes that hydroacoustics could still be useful in gauging the benefits of marine protected areas. The researchers suggest that hydroacoustics could be a more cost-effective method for assessing fish populations.

The study's co-authors include Scripps postdoctoral scholar Andrew Johnson, researchers from Bangor University, and researchers from Centro para la Bioversidad Marina y la Conservación in La Paz, Mexico. The results of this study could pave the way for more efficient and cost-effective methods of monitoring marine life in protected areas, contributing to the conservation and sustainability of our oceans.

Acoustic Innovation in the Spotlight: Utilization of Sound Waves for Estimation of Marine Creature Abundance