Latest news with #CatherineMitchell
Newsweek
25-06-2025
- Science
- Newsweek
Satellite Image Reveals Unexpected East Coast Phenomena: 'Impressive'
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources. Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content. A striking image of a massive bloom of phytoplankton—microscopic plant-like organisms that often float near the surface of the ocean—has been captured from space in the Gulf of Maine. Coccolithophores, a type of phytoplankton that has been less common in the waters off the New England coast since about 2010, "made an impressive appearance" this summer, NASA said in a statement. The image, taken by NASA's PACE (Plankton, Aerosol, Cloud, ocean Ecosystem) satellite, captured of one of the largest blooms of its kind to turn up on the waters of the Gulf of Maine in recent years. Coccolithophores have plates made of calcium carbonate. The light reflecting off the calcium carbonate gives the water a milky blue hue. Catherine Mitchell, a satellite oceanographer at Bigelow Laboratory for Ocean Sciences, notes that coccolithophore blooms such as this one have been less common in the gulf waters over the past 15 years. An image of a massive bloom of phytoplankton captured from space by NASA's PACE (Plankton, Aerosol, Cloud, ocean Ecosystem) satellite. An image of a massive bloom of phytoplankton captured from space by NASA's PACE (Plankton, Aerosol, Cloud, ocean Ecosystem) satellite. NASA Earth Observatory The presence or absence of these tiny organisms—along with other types of phytoplankton—in the Gulf of Maine can impact the entire ecosystem from finfish to shellfish and the local fisheries that depend on them. Phytoplankton form a crucial part of the coastal and open ocean ecosystems and a healthy system houses a diverse range of species. Coccolithophores do not produce any known toxins that are harmful to humans, but dense phytoplankton blooms of any species can potentially cause localized issues, such as low dissolved oxygen levels that can kill fish, microbiologist Brianna King warned in a March article for the Maine government's department of marine resources. Blooms of coccolithophores can also be beneficial for the local environment. For example, their calcium carbonate scales can act as a natural buffer, "dissolving under certain conditions and helping to counter-act ocean acidification on a very localized level," King said. Recent years have seen coccolithophores make a rebound. Researchers have also reported a rise in dinoflagellates—a type of phytoplankton with whip-like tails—and a decades-long drop in phytoplankton productivity. These changes have occurred amid changing water conditions, such as varying temperatures, NASA said. The relationship between these changing water conditions and phytoplankton communities in the gulf is unknown but Mitchell believes ongoing research, with the help of images captured by PACE, could start pointing to some answers. "A major benefit of PACE is its ability to 'see the rainbow,'" Mitchell said, enabling scientists to observe the ocean color in more detail and at a higher resolution than before. Do you have a tip on a science story that Newsweek should be covering? Do you have a question about marine life? Let us know via science@
CBC
29-05-2025
- Health
- CBC
Researchers hope tracking zooplankton from space will help endangered whales
Researchers are hoping a technique that identifies zooplankton from space will eventually help them track the movement of critically endangered North Atlantic right whales in the Gulf of Maine. Scientists at the Bigelow Laboratory for Ocean Sciences in Maine are using NASA satellite data to attempt to identify Calanus finmarchicus, the tiny zooplankton that are the main food source of North Atlantic right whales. The zooplankton, which are smaller than a grain of rice, contain a reddish pigment — the same pigment that makes salmon look pink. When large quantities of the creatures congregate at the water's surface, that pigment affects the spectrum of sunlight that is absorbed and reflected, and the satellite can detect the resulting colour shift. The researchers hope that by tracking the presence of zooplankton, they will someday be able to predict the movement of North Atlantic right whales, and hone attempts to protect them. "The Gulf of Maine conditions have been changing. They've been rapidly warming. And we believe that means their main food source has moved to a different location," says Catherine Mitchell, a senior research scientist at the Bigelow Laboratory and co-author of a new study about the ocean colour technique. "So if we know where the whales are, it could help inform the conversation around their conservation." North Atlantic right whales are nearing extinction, with only about 370 remaining, and only about 70 breeding females. After 17 dead whales were identified in Canada and the United States in 2017, Canada implemented restrictions on fishing and ship speeds in certain areas of the Atlantic region to prevent further deaths due to vessel strikes and entanglements in fishing gear. Knowing where the whales are, and where they might go, could help governments more efficiently use fishing closures or vessel speed restrictions to protect them. Seeing red The Bigelow Laboratory researchers got the idea of using the satellite data to try to find Calanus finmarchicus from a previous study that was done off Norway. But when they started reviewing the data from the Gulf of Maine dating back to 2003, they noticed something unusual. "We were detecting patterns out of the season when we would expect to see Calanus finmarchicus, which made us realize that we were seeing other things too," Mitchell said. The model was picking up not just Calanus finmarchicus, but other zooplankton that contain the same red pigment. Mitchell and Rebekah Shunmugapandi, lead author and post-doctoral scientist at the Bigelow Laboratory, are now trying to refine their method to try to pinpoint the North Atlantic right whale's favourite food species. Shunmugapandi is working to validate some of the satellite data with in-the-water observations from researchers in the Gulf of Maine as well as actual right whale sightings. "They move along with their prey, right?" Shunmugapandi said. "So with all those in situ Calunus and the right whale sighting data set … it's kind of a reverse study that I'm doing." New satellite, new possibilities One potential solution to differentiating Calanus finmarchicus from other red-pigmented zooplankton could be orbiting the Earth right now. The researchers have so far relied on data from NASA's Aqua satellite, but the instrument used to capture the light spectrum, MODIS, is nearing the end of its lifespan. However, NASA's newer PACE (Plankton, Aerosol, Cloud, ocean Ecosystem) satellite, which was launched last year, could vastly improve scientists' abilities to analyze ocean colour. Aqua's light-detecting instrument identifies 10 wavelengths of light. The researchers used only three of its wavelengths for their study. The new instrument aboard PACE, called the Ocean Color Instrument, can detect 280 wavelengths. Shunmugapandi says researchers would need to develop a new computer model to analyze a wider spectrum of light. "The hope is that with much more wavelengths, we might be able to tease out some more things, particularly things actually like the different species," Mitchell says. '1 piece of the puzzle' Currently, zooplankton researchers attempt to identify and track species by collecting them in nets to examine, using video cameras that function as underwater microscopes, and studying acoustics in the water. Catherine Johnson is a research scientist at Fisheries and Oceans Canada who specializes in zooplankton ecology. She says quantifying and identifying zooplankton is difficult because the ocean is so vast and their distribution is variable over space and time. Most sampling techniques work best when they're focused in a specific area or time frame. Johnson, who was not involved in the new study, says remote sensing of zooplankton could be a tool in the toolbox of scientists. "It has the potential to provide good coverage over space and time if you're looking for exceptionally dense and large aggregations that are right near the surface," she said. "It's one piece of the puzzle, and I think that the study is a proof of concept to try to apply these methods in an area where they haven't been applied before." Mitchell and Shunmugapandi agree there's lots more work to be done. "Science is a process and we're not saying that this satellite product we've made is the be-all and end-all answer to understanding where right whales are," says Mitchell. "We are just trying to provide an extra piece of information that could be useful to the story and helpful to people."
