Skip to content

Expedition Planning 101 – How Models Can Help Guide Deep-Sea Exploration

In May 2018, a joint Marine Conservation Institute and Marine Applied Research and Exploration (MARE) expedition will probe the deep seafloor within the Channel Islands National Marine Sanctuary. The sanctuary is home to an astonishing diversity of cold-water corals and sponges that build crucial habitat for a large number of fish and invertebrate species (e.g., Figure 1). These habitats can be considered the ‘old-growth forests’ of the ocean – they are long-lived, slow growing, and extremely slow to recover following disturbance.


Figure 1: A copper rockfish takes refuge near a cold-water coral colony in the Channel Islands National Marine Sanctuary. Photo: MARE


Globally, these fragile deep-sea ecosystems are at significant risk from a growing number of threats including climate change, oil and natural gas extraction, seafloor mining, and fisheries (Ramirez-Llodra et al. 2011). Bottom-trawling fisheries, which drag enormous nets along the seafloor and indiscriminately catch corals and fish, have completely destroyed these habitats in many areas (Puig et al. 2012).


Figure 2: Three dimensional view of predicted habitat suitability for soft corals in the Santa Cruz Passage between Santa Rosa and Santa Cruz Islands.


Only a small percentage of the deep seafloor has been explored. The Channel Islands National Marine Sanctuary spans an expansive 1,470 square miles, a vast area to cover given the expense and technological difficulties associated with surveying deeper waters. Coupled with the fact that cold-water coral and sponge habitats are relatively rare, covering only small patches of the seafloor, simply locating these communities can be difficult. Picking the areas you want to survey is expedition planning 101, but can also be one of the more difficult – and stressful steps. Habitat suitability models are tools that help scientists better map the areas where these deep-sea ecosystems will likely be found. The models link environmental data with locations that are already known to be inhabited, allowing us to predict where we expect to find new communities in unexplored areas (Figure 2, 3, and 4).


Figure 3: A close-up look at the habitat suitability model for soft corals within the Channel Islands National Marine Sanctuary. Warmer colors indicate more suitable habitat.


Figure 4: Diagram showing the basic modeling process used to predict habitat suitability for cold-water corals and sponges in the Channel Islands Marine National Sanctuary (CIMNS).

Since these models can be developed using limited field surveys and remotely sensed data, then used to predict distributions over large seafloor areas, they are particularly useful in improving our understanding of deep-sea distributions. We developed models for five taxonomic groups in the Channel Islands Marine National Sanctuary: soft corals, hard corals, sea pens, black corals, and sponges. These models (e.g., Figure 2, 3, and 4) act as our best estimate of where we expect to find these taxa in completely unexplored areas, and will help us choose sites and plan ROV surveys on our upcoming expedition.

Marine Conservation Institute and Marine Applied Research and Exploration (MARE) have joined together to find and protect sensitive deep-sea corals. Together, we are raising funds to support our 2018 mission off the coast of Southern California. On May 14, the expedition will depart from Santa Barbara to discover never before seen deep-sea corals. MARE will deploy an unmanned robotic submarine to document this deep-sea habitat. With only 3% of the ocean explored – this expedition is sure to bring back critical information about our oceans! We only have until May 10 to reach our campaign goal, and we need your help to save these deep-sea corals. Thank you for joining in protecting our oceans – the life line of our planet. The oceans thank you!


Support our deep-sea expedition with MARE!


Feature Photo: An octopus explores the deep sea, by MARE.



Puig P, Canals M, Martín J, Amblas D, Lastras G, Palanques A, Calafat AM. 2012. Ploughing the deep sea floor. Nature

Ramirez-Llodra E, Tyler PA, Baker MC, Bergstad OA, Clark MR, Escobar E, Levin LA, Menot L, Rowden AA, Smith CR, Van Dover CL. 2011. Man and the last great wilderness: human impact on the deep sea. PLoS One. 6(8):e22588.



  1. […] Author: Sam Georgian / Source: Marine Conservation Institute […]