Within the waters off New England, one in all Earth’s rarest mammals swims slowly, mouth agape. The North Atlantic proper whale filters clouds of tiny reddish zooplankton — referred to as Calanus finmarchicus — from the ocean. These zooplankton, no greater than grains of rice, are the whale’s lifeline. Solely about 370 of those huge creatures stay.
For many years, monitoring the tiny plankton meant sending analysis vessels out within the ocean, towing nets and counting samples by hand. Now, scientists are trying from above as a substitute.
Utilizing NASA satellite tv for pc knowledge, researchers discovered a option to detect Calanus swarms on the ocean floor within the Gulf of Maine, selecting up on the animals’ pure pink pigment. This early-stage strategy, described in a brand new examine, might assist researchers higher estimate the place the copepods collect, and the place whales would possibly comply with.
Monitoring the zooplankton from house might assist each the whales and maritime industries. By predicting the place these mammals are prone to feed, researchers and marine useful resource managers hope to cut back lethal vessel strikes and fishing gear entanglements — two main threats to the species. Understanding the feeding patterns might additionally assist transport and fishing industries function extra effectively.
“NASA invests in this type of analysis as a result of it connects space-based remark with real-world challenges,” mentioned Cynthia Corridor, a help scientist at NASA headquarters in Washington. She works with the Early Profession Analysis Program, which partly funded the work. “It’s one more a option to put NASA satellite tv for pc knowledge to work for science, communities, and ecosystems.”
Revealing the Ocean’s Hidden Patterns
The brand new strategy makes use of knowledge from the Reasonable Decision Imaging Spectroradiometer (MODIS) aboard NASA’s Aqua satellite tv for pc. The MODIS instrument doesn’t immediately see the copepods themselves. As a substitute, it reads how the spectrum of daylight mirrored from the ocean floor adjustments in response to what’s within the water.
When giant numbers of the zooplankton rise to the floor, their reddish pigment — astaxanthin, the identical compound that provides salmon its pink coloration — subtly alters how photons, or particles of sunshine, from the solar are absorbed or scattered within the water. The destiny of those photons within the ocean will depend on the combination of dwelling and non-living matter in seawater, making a slight shift in coloration that MODIS can detect.
“We didn’t know to search for Calanus earlier than on this method,” mentioned Catherine Mitchell, a satellite tv for pc oceanographer at Bigelow Laboratory for Ocean Sciences in East Boothbay, Maine. “Distant sensing has sometimes targeted on smaller issues like phytoplankton. However latest analysis prompt that bigger, millimeter-sized organisms like zooplankton may affect ocean coloration.”
Just a few years in the past, researchers piloted a satellite tv for pc methodology for detecting copepods in Norwegian waters. Now, a few of those self same scientists — together with Mitchell’s crew — have refined the strategy and utilized it to the Gulf of Maine, a vital feeding floor for proper whales throughout their northern migration. By combining satellite tv for pc knowledge, a mannequin, and subject measurements, they produced enhanced pictures that exposed Calanus swarms on the sea floor, and have been in a position to estimate numbers of the tiny animals.
“We all know the proper whales are utilizing habitats we don’t absolutely perceive,” mentioned Rebekah Shunmugapandi, additionally a satellite tv for pc oceanographer at Bigelow and the examine’s lead writer. “This satellite-based Calanus info might finally assist establish unknown feeding grounds or higher anticipate the place whales would possibly journey.”
Monitoring Elusive Giants
Regardless of a long time of examine, North Atlantic proper whales stay remarkably enigmatic to scientists. As soon as pretty predictable of their actions alongside the Jap Seaboard of North America, these huge mammals started abandoning some conventional feeding grounds in 2010-2011. Their sudden shift to sudden areas just like the Gulf of Saint Lawrence caught individuals off guard, with lethal penalties.
“We’ve had whales getting hit by ships and whales getting caught in fishing gear,” mentioned Laura Ganley, a analysis scientist within the Anderson Cabot Heart for Ocean Life on the New England Aquarium in Boston, which conducts aerial and boat surveys of the whales.
In 2017, the Nationwide Oceanic and Atmospheric Administration designated the scenario as an “uncommon mortality occasion” in an effort to handle the whales’ decline. Since then, 80 North Atlantic proper whales have been killed or sustained severe accidents, in response to NOAA.
Within the Gulf of Maine, there’s much less transport exercise, however there is usually a advanced patchwork of lobster fishing gear, mentioned Sarah Leiter, a scientist with the Maine Division of Marine Assets. “Every fisherman has 800 traps or so,” Leiter defined. “If a bigger variety of whales reveals up instantly, like they only did in January 2025, it’s difficult. Fishermen want time and good climate to regulate that gear.”
What excites Leiter probably the most concerning the satellite tv for pc knowledge is the potential to make use of it in a forecasting instrument to assist predict the place the whales might go. “That might be extremely helpful in giving us that essential lead time,” she mentioned.
PACE: The Subsequent Era of Ocean Observer
For now, the Calanus-tracking methodology has limitations. As a result of MODIS detects the copepods’ pink pigment, not the animals themselves, which means different small, reddish organisms could be mistaken for the zooplankton. And cloud cowl, tough seas, or deeper swarms all restrict what satellites can spot.
MODIS can also be nearing the tip of its operational life. However NASA’s next-generation PACE (Plankton, Aerosol, Cloud, ocean Ecosystem) satellite tv for pc — launched in 2024 — is poised to make dramatic enhancements within the detection of zooplankton and phytoplankton.
“The PACE satellite tv for pc will certainly be capable to do that, and perhaps even one thing higher,” mentioned Bridget Seegers, an oceanographer and mission scientist with the PACE crew at NASA’s Goddard House Flight Heart in Greenbelt, Maryland.
Native information of seasonal plankton patterns will nonetheless be important to interpret the info appropriately. However the purpose isn’t excellent detection, the scientists say, however reasonably to offer one other instrument to tell decision-making, particularly when time or sources are restricted.
By Emily DeMarco
NASA Headquarters
