Expedition log by Science Communication Fellow Marike Pinsonneault

The opening days at sea have been defined by preparation, discovery, and the kind of adaptive problem-solving that fieldwork demands.

Winds on day two prompted a shift from our primary dive site, Sur Ridge. Choppy weather makes launch and recovery of the MiniROV more challenging, so the team determined it would be safer to survey Sponge Ridge instead. Located inside Monterey Bay, this research site is approximately 550 meters (1,800 feet) deep and is more protected from the winds. 

Over the days that followed, the team refined workflows and carried out mapping operations at a site already familiar to the CoMPAS Lab. While portions of the ridge have been charted in previous work, the newly generated maps will meaningfully contribute to MBARI’s ongoing monitoring of Monterey Bay, enabling comparisons of seafloor change across multiple scales, from geological processes visible at meter-scale resolution to subtle shifts in marine life, such as the growth of sponges previously mapped by the CoMPAS Lab, captured at centimeter and millimeter scales. 

Next, we’ll explore a research site nicknamed “Central Slope Corals,” a location the CoMPAS Lab hasn’t mapped before. The name says it all—this rocky crest is home to various coral species and offers ample opportunities for the CoMPAS Lab to create new dynamic maps that can be built on in the future to monitor corals and topography. Central Slope Corals is much deeper than Sponge Ridge. Located approximately 1,100 meters (3,600 feet) underwater, this dive will be great practice for diving at Sur Ridge this weekend when the weather improves.

These dives also served as a valuable engineering test, putting new tools through challenging weather conditions—testing the machine-learning-assisted laser scanner under varying turbidity, lighting, and visibility, and evaluating the vehicle controller in the presence of currents and swell. 

The weather may have reshaped our original plans, but it has not slowed us down. With Sur Ridge dives on the horizon, the second half of this expedition is shaping up to be even more rewarding than the first!