Wednesday, February 17, 2021

Protecting a refuge of coldness

        This probably isn’t news to most readers, but our winters aren’t as cold as they used to be. Scientists who recently examined 100 years of winter temperature and precipitation data from weather stations across the Northeast found clear indications of that fact.
        They noted, for example, that there are now fewer days when daytime temperatures never go above freezing; fewer days when nighttime temperatures dip below freezing; and fewer days when temperatures sink below 0 F. They also concluded that the cold period of the year is now three weeks shorter than it used to be.
        For some of us, that’s something to celebrate. Fewer days of mind-numbing cold, snowy roads and frost-covered windows are a welcome respite from our winters of old. But not all creatures would agree.
        Snow cover provides an insulating blanket on top of the soil, keeping it from freezing too deeply and enabling some soil processes to continue unabated. Snow cover also provides important wildlife
habitat for many small mammals that create hidden travel corridors between the soil and snow layers. Shorter winters with fewer cold days also mean that disease-carrying ticks and invasive mosquitoes can expand their ranges northward, and more tree-killing pests will survive the winter.
        These revelations made me wonder whether it might be worthwhile to identify and protect refugia of coldness, places where cold-loving species can thrive. Are there locations on the landscape that are more likely to retain cold conditions and snow cover for longer periods? Can we manage a few nooks and crannies of the Ocean State as islands of coldness?
        It may sound at first like a strange concept, but it’s worth considering. If we want to continue to have black spruce trees in Rhode Island, for instance, we may need to preserve a few pockets of coldness. We’re at the southern end of the range of this cold-loving conifer, and as temperatures warm, the local conditions will likely soon become inhospitable to its growth.
        There are bound to be other species whose survival may be compromised by a reduction in cold conditions. A scan of the Rhode Island Natural Heritage Database would probably find other species that are barely hanging on in the state and may be pushed over the edge by too much winter warming.
        Identifying refugia of coldness shouldn’t be too difficult. Television meteorologists often mention the coldest places in the state during their forecasts, places like the valleys and north-facing slopes in the northwest corner of Rhode Island. There are plenty of cold pockets and frost hollows elsewhere in the state, too, locations where the first frost comes days or weeks before sites nearby.
        My friend David’s house in Wakefield is one such place. It sits in a broad valley where cold accumulates, and on some chilly mornings when he leaves his house and drives up a short rise in the road just past his driveway, he experiences a noticeable temperature increase.
        Someone with expertise in Geographic Information Systems would have no difficulty identifying other such areas. These sites don’t necessarily have to be the coldest places in the state, where the lowest low temperatures occur, however. It may be useful to also identify those places defined by temperatures that are simply less warm than elsewhere. Either way, it would be a worthwhile exercise, even when there are plenty of other factors to consider when deciding what lands to preserve.
        For it’s easy for humans to come in from the cold, but harder and harder for some species to find enough of it.

        This article first appeared in The Independent on Feb. 6, 2021.

Monday, February 8, 2021

A year in the ice in the Arctic

        It was planned as the largest Arctic science expedition in history: trapping the German icebreaker Polarstern in the ice near the North Pole for 13 months as 600 scientists from 19 countries collected urgently-needed data on the Arctic ecosystem and the interactions between the atmosphere, ocean and sea ice. But when the COVID-19 pandemic struck a few months after the project started, it led to innumerable challenges that disrupted the work, delayed the transfer of personnel, and required the establishment of new protocols.
        Yet through it all, the research team – including five scientists from the Graduate School of Oceanography – persevered and completed most of what they set out to accomplish.
        “This project was 10 years in the making,” said Brice Loose, GSO associate professor and one of the organizers of the expedition. “There was a recognition among many disciplines within the Arctic

sciences that there had been an extreme regime shift in the way the ocean and atmosphere were working. What we thought we knew about the Arctic didn’t necessarily apply anymore.”
        The $150 million MOSAIC expedition (Multidisciplinary Drifting Observatory for the Study of Arctic Climate) sought new insights from the epicenter of the changing climate as well as some of the first oceanographic data gathered from the region during winter. To collect a baseline understanding of what some are calling the New Arctic required an interdisciplinary approach and a year of continuous data collection to enable scientists to observe the complete life cycle of plankton and the physical processes taking place from month to month and season to season.
        But why get trapped in the ice? In part, it was the most practical solution, Loose said. It’s not feasible to navigate the ice flows throughout the winter, and it allowed scientists to use the ice as a platform for conducting their studies.
        “The atmosphere is moving at one speed and direction, the ice is moving at a different speed and direction, and the ocean is moving at a third speed and direction,” he said. “We just had to pick a frame of reference and stick with it.”
        Aboard ship at various times during the year, Marine Research Scientist Robert Campbell, Marine Research Specialist Celia Gelfman and Postdoctoral Fellow Katy Shoemaker studied the feeding, growth, reproduction and respiration of the Arctic zooplankton community.
        “We focused on a few key species throughout the drift and tried to get a better understanding of

their complete life cycles,” said Campbell, who spent several months on the ship last winter and again this fall. “We’re using the measurements we made to better understand the Arctic planktonic food web and to quantify energy flow and nitrogen and carbon transformation processes throughout the planktonic ecosystem.”
        A typical day for Campbell started with experimental readings before breakfast and often didn’t conclude until well after midnight. He worked from the ship three or four days each week deploying CTDs to collect water samples as deep as 4,000 meters and to measure salinity, pressure, depth and other variables. They also deployed net systems, cameras and particle counters to collect and count plankton from different depths. During other days he worked from the ice, drilling and collecting ice cores for other studies or sampling plankton with small nets from a hole in the ice.
        “On Saturdays we got to use the ‘Beast’, an ROV that has its own container on the ice away from the ship and is equipped with plankton nets,” he said. “We used it to collect plankton samples directly under the ice.”
        For Gelfman, the hardest part of the expedition was just getting to the ship. By the time her leg of the expedition was approaching, the pandemic was in full swing. After more than a month of delay, she, Shoemaker and Postdoctoral Fellow Alessandra D’Angelo flew to a hotel in Germany for two weeks of isolation, then boarded a ship to Svalbard where the Polarstern exchanged personnel after leaving the icepack. The entire process took more than a month.
        Once the ship was back in the ice, Gelfman fell into a similar routine as Campbell had before her. But rather than extreme cold and near total darkness all day long, she enjoyed round-the-clock daylight and temperatures that hovered around freezing.
        “For me, what was most interesting to think about was that we were on a boat moving with a flow of ice, so every time we put our nets in the water, the ice itself was always the same but the water underneath was always different,” she said. “We were moving through seasonal time, but also through geographic space. As a result, there’s going to be a lot of stuff we’re going to have to correlate in our analysis.
        “We also experienced a freshwater lens from the meltwater on the ice,” Gelfman added. “As the ice melted, it made a layer of freshwater on the surface, and it seemed like we had a plankton bloom that was related to that freshwater melt and release of nutrients. We sampled during those conditions, and I’m excited to see the progression of young stages of copepods feeding during that part of the year.”
        Loose’s research examined the occurrence of a group of microorganisms that produce or consume methane and their role in mitigating the release of large quantities of methane from the ocean bottom, which is hypothesized will take place as a result of the changing climate.
        “A tremendous amount of methane is trapped in the seafloor, more than you’d ever want to have get into the atmosphere,” Loose said “It’s trapped in one kind of ice or another, and that ice is stable at certain temperatures and pressures. But if the temperature or pressure changes, a lot of that methane could be released into the water column. Our question is, will that methane make it to the atmosphere, or will the microbes eat it first?”
        Since Loose didn’t spend any time aboard the ship, most of his data collection was left to D’Angelo, the team leader for all of the biogeochemical studies during the expedition. She collected ice core and seawater samples every week to analyze their methane and carbon dioxide concentrations and isotopic ratios.
        “We want to know the rate of oxidation or production of methane by the microbes so we can understand how much might be released into the atmosphere,” she said. “The more sea ice there is, the less methane will be exchanged with the atmosphere because the ice blocks the exchange.”
        All of the GSO participants in the expedition had joined many previous Arctic research cruises, but the total number of scientists involved in the MOSAIC expedition and the variety of disciplines they represented made this one special.
        “I really appreciated the effort everyone put into building new research ideas and new collaborations,” D’Angelo said. “We were very, very busy, so you don’t expect to have extra time to work on other research projects, but we were very willing to do it anyway. We created new research activities in parallel with our work. It was a good way to develop new ideas, new networks, and new collaborations for future proposals.”
        One variable in the daily activity that was impossible to predict was the presence of polar bears. While Gelfman, D’Angelo and Shoemaker were aboard, they saw polar bears nearly every day, and if the bears approached too closely, research activities on the ice had to be curtailed. “It was very nice to see polar bears when we were on the ship,” D’Angelo quipped, “but not so nice when we were on the ice.”
        While pandemic protocols made it difficult for the scientists to get to the ship and back home again – and many scientists never made it to the ship at all due to restrictions in their home countries – the virus wasn’t something they thought much about while at sea. “The coronavirus didn’t touch us on the ship, but now that we’ve come back it seems strange to have to wear a mask,” said D’Angelo. “Everything is so different and new.”
        Although there is still a great deal of data analysis to be done with the samples collected during the expedition, the scientists have already made some interesting observations.
        “We found that most animals in winter were found at depth, 500 to 2,000 meters in diapause, and some of these were already producing eggs in December that would float to the surface so that their offspring would be ready to feed on the spring bloom once it started in late spring,” Campbell said. “This is a very important life cycle strategy given the short growing season. We also found that some animals remain active in the surface during the winter. How were they fueling this activity during the polar night when food is so limiting? We hope to find this out from our analysis of the DNA of the prey items in their stomach contents.”
        On the last day of her quarantine after returning home from the Arctic, Gelfman said that one of the things she most appreciated during the MOSAIC cruise was the opportunity to walk around on the ice on a regular basis.
        “It’s a place that not many people get to see, and it’s so diverse and different every week,” she said. “There would be surface melting that would refreeze at night, and the ice crystal formations were always interesting. Like most cruises, it was wonderful to spend every day focused on your work and not everything you usually have to juggle in your life. But this one was special in so many ways – great people, great science, great place.”

        This article first appeared in the winter 2021 issue of Aboard GSO.

Friday, February 5, 2021

Dolphins strand along Rhode Island coast

        When a dead dolphin was discovered at Cormorant Cove on Block Island on January 17, a volunteer with the Mystic Aquarium Animal Rescue Team responded to the scene to collect data about the animal. A week later a second dead dolphin was discovered on Block Island near the North Light, and the same process was repeated. Two others were found dead off Ocean Drive in Newport in December.
        The dolphin deaths have some people worried and wondering what could be killing the animals. Might there be something unhealthy in Rhode Island waters?
        Scientists don’t think so. Instead, they believe the dolphin mortalities are probably due to natural
Common dolphin found on Block Island (Kim Gaffett)

attrition in a large population of dolphins that is typically most active in southern New England waters in fall and winter.
        Three of the four dead dolphins were common dolphins, a species that University of Rhode Island oceanographer Robert Kenney, writing in a blog in 2017, described as “the most abundant cetaceans off the Atlantic coast, with perhaps 240,000 or more between Florida and Labrador.” They also occur in tropical and temperate waters elsewhere around the world, and they sometimes aggregate into extremely large herds.
        Kim Gaffett, a naturalist with The Nature Conservancy and a board member of the Rhode Island Natural History Survey, was on hand when the aquarium volunteer responded to the Block Island dolphins. She said that common dolphins are regularly observed around the island in winter – and occasionally in summer – with most sightings coming from passengers on the Block Island ferry. She said dead dolphins are observed on the island shoreline about every other year.
        Neither of the dead Block Island dolphins had any visible signs of injury, according to Gaffett. Based on photos of the animals Gaffett provided, Kenney believes the animals were relatively old in age.
        The aquarium did not conduct a necropsy – an animal autopsy – on any of the recently reported dolphins, so their cause of death is unknown. Animals that appear to have died more than 24 hours previously are usually left to drift back out to sea, said Sarah Callan, assistant manager of the aquarium’s Animal Rescue Program, since the decomposition process would make their tissues too deteriorated to be useful in determining cause of death. Since necropsies require several people working in close proximity, the aquarium is conducting fewer necropsies during the COVID19 pandemic to reduce the risk to its staff and volunteers.
        Callan wouldn’t speculate about the cause of death of the dolphins found recently in Rhode Island waters, though she said it could be from any number of factors, including disease, respiratory infections, vessel strikes, fishing gear entanglements or various natural causes. She also noted that it isn’t uncommon for as many as 10 dolphins to strand in local waters in a typical year.
        “Every year is different,” she said. “Often when animals die, whether from natural causes or something else, where they wash up depends a lot on the weather and currents. It could be a fluke of the currents that pushed those two dolphins to Block Island. Animals that died on Cape Cod can even end up here. There are so many factors involved. It doesn’t necessarily indicate something has happened off our shoreline.”
        Data from an April 2020 assessment of common dolphins in the western North Atlantic by the National Oceanic and Atmospheric Administration estimated that 419 common dolphins are killed as fisheries bycatch each year. The same report indicated that 28 common dolphins were found stranded on Rhode Island beaches between 2013 and 2017 and 359 on Massachusetts beaches during the same period, including 166 in 2017 alone.
        Kenney said that when individual dolphins are found dead, it is typically because the animal was sick or injured. And while there are occasionally spikes in mortality due to disease, which the federal government labels an “unusual mortality event,” no such event has been declared for common dolphins anywhere on the East Coast in recent years.
        Kenney isn’t concerned about the health of the common dolphin population in southern New England, despite the number of animals found dead this winter.
        “If a marine mammal population is stable, an equal number of animals should be expected to die and be born every year,” he said. “Given that the current estimate for common dolphin abundance in the regional population is 172,825, if natural mortality is only one or two percent a year, there should be 2,000 to 3,000 dead ones every year.”
        In addition to common dolphins, Callan said that mid-winter is also a common time for gray seal pups to be found washed up on area beaches, both dead and alive, some of which may have originated as far away as Canada or Greenland. Anyone who finds a stranded marine mammal should call the Mystic Aquarium hotline at 860-572-5955, extension 107.

        This article first appeared on EcoRI.org on February 4, 2021.

Monday, February 1, 2021

Eating the invaders

        The scourge of invasive species is taking over the landscape. During a walk around almost any local park, you’re likely to find just about as many non-native species as native ones, and scientists say that the worst offenders are outcompeting native plants and interfering with the intricate relationships between native birds, insects, plants and other wildlife.
        And yet most invasives are here to stay; it’s almost impossible to eradicate them.
        “Because they’re not from around here, they don’t have the typical predators and diseases that keep them in check in their native land,” said Dave Gumbart, director of land management for the Connecticut office of The Nature Conservancy. “Once they’re established, they’re very capable of spreading and becoming aggressive.”
        At the Conservancy’s properties, Gumbart and his staff deploy a variety of tactics to fight the worst invaders. They manually cut them back, dig them out, and apply targeted herbicides, but it seems to be a never-ending battle.
        One step they haven’t tried, however, is eating them, and yet many chefs are taking that unusual step.
        Bun Lai, the chef and owner of Miya’s Sushi in New Haven, has been doing just that for nearly 20 years, ever since he was flipping rocks along the shoreline in Branford with a friend and started to see 
Fried Asian shore crabs prepared by Bun Lai (Eric Heimbold)
creatures he had never seen before.
        “I was just starting to promote sustainable seafood, and it dawned on me that maybe we should start thinking about invasive species as an alternate food source,” he said. “Slowly we started getting into it.”
        Today, Lai is among the national leaders of this growing movement. His restaurant’s menu features an extensive variety of invasive species, from pickled burdock root and garlic mustard falafel to Asian shore crabs caught in Long Island Sound. He even serves a saké drink made with the berries of the invasive autumn olive shrub. And although he will be closing his restaurant at the end of the year, Lai will continue to serve invasive species at Miya’s pop-up restaurants around the region, and he plans to market other invasive species-based food products.
        “Many of these plants are exponentially more nutritious than anything you can grow on an organic farm,” Lai said, “because they’re wild plants. Over 16,000 years we’ve cultivated for flavor, size, beauty and resilience but not for nutrition.”
        That’s not to say that they don’t taste good, especially when cooked by an expert like Lai. He said that invasive Japanese knotweed, a large abundant perennial that causes millions of dollars in damage to native environments around the country each year, is every bit as tasty as rhubarb. He serves it in multiple ways, including pickled and as a tea.
        He noted that invasive dandelion flowers also make an excellent tea and an even better liqueur that tastes like butterscotch candy. And mugwort, an Asian member of the daisy family, tastes like a powerful sage that he purees into rice.
        “Invasive garlic mustard tastes exactly the way it’s named – like garlic and mustard,” Lai said. “It’s pungent, and the leaves are very hardy. We put it in salads, sauté them, or put them in a soup with a bunch of other foraged weeds. I really think you can’t eat anything healthier.”
        James Wayman agrees. The executive chef at The Oyster Club in Mystic uses the root of garlic mustard as a horseradish substitute. “But my favorite part is that they have these lovely florets, almost like a broccoli or flowering kale, that I turn into pesto,” he said.
        Wayman became interested in eating invasive species while foraging for mushrooms and other edible wild plants. He said he doesn’t necessarily seek out plants because they are invasive. Instead, he selects invasive plants largely because they are abundantly available and delicious. He especially likes cooking with Japanese knotweed, which he pickles, uses as a vegetable or makes into a syrup that he serves over ice cream. He also makes autumn olive berries into a caramel.
        Both chefs get their invasive ingredients simply by walking around their own properties, at partner farms, and while enjoying nature. “We have everything I need right nearby,” Lai said. “I just step outside my door and pick it.”
        Customer reaction to seeing invasive species on the menu can vary, but once people taste them, they become believers. “We’ve done some foraged dinners and had a great response,” Wayman said. “My customers really become interested in it because they’re flavors that are different from what they’re used to.”
        Unfortunately, even if the consumption of invasive species became trendy, it’s not likely that it would have much of an impact on the abundance of invasives on the landscape. But that doesn’t make the effort any less worthwhile.
        “We’re not going to eat our way out of the invasive species problem,” Lai concluded. “We’ll never be able to turn the ecosystem around to what it was before. But the reality is that invasive species aren’t all bad, and eating them is part of the solution to the bigger problem of trying to make our food system sustainable.”

        This article first appeared in the November 2020 issue of Connecticut Magazine.