This year marks the 50th anniversary of the National Marine Sanctuaries, a crowning conservation achievement akin to National Parks. Places with this designation protect 620,000 square miles of beautiful and diverse ocean and Great Lakes habitats for future generations. By protecting ecosystems and sustainable fisheries, as well as promoting tourism and recreational opportunities, the sanctuaries and other coastal habitats contribute $160 billion to the $373 billion blue economy, according to National Oceanic and Atmospheric Administration estimates. Sanctuary managers are turning to new information technology to identify emerging threats to ocean life caused by the absorption of excess heat and carbon dioxide produced by human industrial activity.
From 2014-2015, a massive marine heat wave, dubbed “the blob,” developed in the Gulf of Alaska and spread down the West Coast triggering a cascade of harmful events from Washington to Southern California. Higher ocean temperatures can stress ecosystems by decreasing marine productivity and oxygen levels and disrupting the balance of microscopic algal species, called phytoplankton, to favor harmful species. Some toxic algae produce high levels of a neurotoxin that accumulates in the marine food chain — including important shellfish species such as mussels, clams and crabs — and poisons shellfish-consuming marine mammals and humans.
The most severe harmful algal bloom (HAB) ever recorded in Monterey Bay and along the West Coast occurred in the aftermath of the blob and led to the closure of the West Coast Dungeness crab season, costing the fishery some $100 million. The marine heat wave also contributed to a 95 percent decline in coastal kelp forests in California and Oregon and the loss of countless seabirds, sea lions and whales.
The severity of the 2015 marine heat wave took the oceanographic community by surprise; no climate records or forecasts had predicted such a devastating event on the West Coast. Seven years on, fishery scientists and ecologists are still working to document and understand the long-term impacts of heat-laden waters on important and productive marine ecosystems and develop strategies to provide early-warning alerts and forecasts and to develop effective habitat restoration.
Monitoring marine life is difficult, as marine plants and animals are usually hidden from view below the ocean’s surface. Plankton, which feed ocean food webs and can cause harmful algal blooms, are microscopic and spread in three dimensions with the tides and currents. Whales and other marine mammals come to the surface to breathe, but can swim hundreds of miles in a day, making their detection a hit-or-miss affair. Sharks and turtles along with large, commercially valuable fish traverse ocean basins to feed and mate. Kelp forests canopies are visible on the surface, but life among the fronds and on the seafloor is typically hidden to all but the occasional scuba diver.
To meet this challenge, teams of engineers, oceanographers and biologists have been working on new and expanding technologies to document and study life in the changing ocean and advance our understanding of the ways that physical and biological systems interact. Autonomous observing systems have the potential to contribute to expansive biological datasets that are otherwise scant or unavailable to scientists and marine managers.
These new technologies include eDNA, which uses adapted genome technology to detect the molecular presence of species through fragments of DNA left in the water column. Like forensic scientists on the scene of a crime, autonomous eDNA sampling from a ship or robotic underwater vehicle can detect if whales have been nearby or whether an area is a biodiversity hotspot and worthy of becoming a marine sanctuary.
Another promising new tool is the Imaging FlowCytobot (IFCB), a robotic microscope that photographs and counts individual phytoplankton cells and, using artificial intelligence similar to facial recognition software, identifies individual harmful and beneficial species in near real time. Other biological observing platforms deploy underwater cameras and ocean sound recordings, which can detect nearby fish schools and distant whales as well as tagged sharks and seals that carry a sensor package to record their movements and the physical environment they swim through. Data from these animal oceanographers is even being relayed by satellite to improve daily weather forecasts.
This wealth of biological data is being added to a growing worldwide database of physical and geochemical observations. These data come from continuously operated buoys, ocean gliders and drones, ship-based data collection, cabled ocean-floor observatories and other environmental sensors. The devices record oceanographic and biogeochemical conditions in real time including temperature, salinity, currents, oxygen and dissolved carbon dioxide that can lead to harmful ocean acidification.
Like all “big data,” these observational datasets hold great promise for understanding complex systems and forecasting future scenarios. For marine scientists, this can mean the prediction of individual events, like a coming marine heat wave or harmful algal bloom, or the creeping impacts of warming ocean temperatures and ocean acidification on marine ecosystems and fisheries. But this emerging informational wealth is running a race against the growing use of and damage to ocean resources. Harnessing trillions of observations into actionable science and conservation depends on making datasets accessible, interoperable and translatable into visualizations, tools and forecasts that decision-makers, scientists and the public can use to change humanity’s relationship to the ocean and help us become more sustainable and responsible in our actions. Ocean data will be critical in determining optimum locations for offshore wind farms and measuring how wind turbines affect fisheries and ocean life.
Biological data can also help sanctuary managers monitor the effectiveness of ecosystem restoration, including the Northern California kelp forests. Scientists there are monitoring kelp canopies using satellites and drones as well as identifying refuge locations where divers can plant and protect kelp from over-predation, giving the forests an opportunity to grow and regain their former range. While continuing to monitor the ecosystem and environmental conditions by traditional methods, eDNA can detect the presence and relative abundances of predators and kelp-grazers and track the health of the underwater forest.
On both local and global scales, these maturing marine life observing capabilities will provide critical information to continue protecting and managing important marine resources and to find new ocean-based solutions to mitigate global environmental change.
Henry Ruhl, Ph.D., is director of the Central and Northern California Ocean Observing System (CeNCOOS), a regional association of the national Integrated Ocean Observing System. Ruhl is also an investigator in the Marine Biodiversity Observation Network (MBON) and other related initiatives.
Mary K. Miller is a science and environment writer and emeritus program director for environmental science at the San Francisco Exploratorium. She works closely with the ocean observing and conservation communities in California and serves on the board of CeNCOOS and the Sanctuary Advisory Council for the Greater Farallones National Marine Sanctuary.