Friday, February 21, 2020

Whale behaviors make them vulnerable to ship strikes, entanglements

            Recent advances in technology have allowed scientists to learn so much more about wildlife during times when the animals are inaccessible to human observation. Songbirds are now capable of wearing tiny backpacks equipped with sensors and satellite technology that are revealing insights into their migratory behavior, for instance. Even bees, butterflies and dragonflies are being tagged to track their movements.
            In the marine environment, scientists are using suction cups to temporarily attach
Breaching humpback whale (Todd McLeish)
whales with a variety of devices that capture video and audio and the depth and location of their underwater activities. That information is being used to better understand how and why whales are at risk of being struck by large ships or becoming entangled in fishing gear.
            In a lecture Feb. 13 at the University of Rhode Island’s Bay Campus, sponsored by Rhode Island Sea Grant, the research coordinator at the Stellwagen Bank National Marine Sanctuary, David Wiley, discussed the feeding strategies used by humpback whales in the sanctuary located in the waters between Boston and Provincetown and how those behaviors increase their risk of mortality.
            “There’s a sand lance culture at Stellwagen Bank,” said Wiley, referring to the 6- to 8-inch fish the whales eat. “The Stellwagen humpbacks don’t go to Jeffrey’s Ledge 40 miles away because that’s a herring area, and the Jeffrey’s Ledge humpbacks that eat herring don’t go to Stellwagen. They’ve developed these cultures that allow them to be very productive in this habitat, and they try to stay in this habitat.”
            Based on the video data collected in recent years, Wiley said the whales scrape their jaws along the seafloor to capture sand lance as the fish try to escape from their hiding places in the sediments. But he believes that the whales coordinate their behavior to improve their odds of catching a meal.
            When feeding at night or in deep water, where visibility is particularly poor, two or three whales dive to the seafloor together and orient themselves head to head.
            “You can see them almost touching each other, rostrum to rostrum, as they try to capture these fish,” Wiley said. “They do it as a group and push the fish toward each other as the fish rocket out of the bottom.”
            To further prove that this is a cooperative behavior, rather than a competitive one, he showed that the same whales almost always orient themselves in the same compass position relative to one another. Relative to a tagged whale, one untagged whale was positioned at the same angle in the feeding group 96 percent of the time, while a second untagged whale was consistently oriented at an angle between the first two 67 percent of the time.
            Wiley also collected data about the whales as they fed at the surface in a behavior called bubble-netting, when the whales blow bubbles to herd their prey together before capturing them. Again, the whales appear to coordinate their feeding by orienting themselves at similar angles and even opening and closing their mouths at the same time.
            “They orient themselves in a star formation and synchronize their engulfment, so it’s clearly a group feeding behavior and a cooperative behavior,” he said.
            In one version of the bubble-netting behavior, the whales also slap their tails at the surface in between blowing bubbles. Why they do so is a mystery.
            “They slap their tails over and over again, so it must have an adaptive value, but we really don’t know,” Wiley said. “People used to think it was to stun the fish, but we’ve never seen stunned fish. We think the percussion scares the fish and makes them aggregate into a tighter school, but we can’t really see what goes on in a bubble net because there’s so much happening at once.”
            How do these behaviors make the whales more vulnerable to becoming entangled in fishing gear or struck by ships?
            According to Wiley, bubble-netting is a feeding strategy used exclusively during daylight hours because that’s the only time when sand lance swim near the surface, and that’s when ship activity is highest. The whales feed on sand lance at the seafloor almost exclusively at night, when visibility is poorest, and they may not see the lobster traps and other fishing gear on or near the bottom. And because most fishing gear has ropes from the bottom to buoys at the surface, entanglement risk is high at whatever depth the whales are in.
            They’re vulnerable to vertical lines 100 percent of the time, Wiley said. They spend 50 percent of their time near the surface during the day when they could get struck by a boat. They spend 50 percent of their time feeding on the bottom at night where they’re vulnerable to fishing gear.
            “Humpback whale vulnerability comes from the fact that this is how they have to live. Their lives depend on being at that place in the water column,” he added. “The only way to reduce this risk is to reduce the amount of human activity that co-occurs or by reducing its penetration into the water column.”

This article first appeared on EcoRI.org on Feb. 20, 2020.

Tuesday, February 18, 2020

Time to go owling

            The freezing temperatures in February make it difficult to force myself out the door after dark. And knowing that I’ll be standing around outside for extended periods while trying to stay completely silent doesn’t make it any easier. But hearing just one distant hoot warms my bones and makes the experience worthwhile.
            Mid-winter is the ideal time to search for owls in Rhode Island, even on years like this one when visiting snowy owls are absent. Great horned owls, the largest resident owl in the
Barred owl (M.E. Sanseverino)
area, are already sitting on eggs or caring for nestlings, so it’s my first target species whenever I go owling. Standing up to two feet tall and with a wingspan of more than four feet, their silhouette is easily identified on a moonlit night by the feather tufts on their head that give them their common name. But it’s their low booming voice that I seek.
            I drive along forested roads, occasionally stopping to listen for a few minutes, especially where forests abut farm fields. Unlike most of the region’s other owls, which feed primarily on mice and voles in the woods, great horned owls are large enough to target rabbits and squirrels, and the forest edge is a great place to watch and listen for them. Most of the time, I hear nothing but traffic noise, an occasional dog bark, and the blood pumping through my head as I strain to hear anything resembling an owl.
            And then I hear it. The unmistakable sound of an owl. One hoot is enough to call the night a success, but when a second owl responds with a series of hoots of its own, I know I’ve hit the jackpot.
            Sometimes, instead of a great horned owl I hear the who-cooks-for-you call of a barred owl, though they are much more active a little later in the season. And rarely – like maybe only a few times in my life – I’ve heard a tiny screech owl spontaneously burst forth with its high-pitched whinny. They’re just as common as the other two species and can be found in similar forested habitat, but they seem to have much less to say. At least when I’m paying attention.
            If standing around in the dark listening – usually in vain – for an owl isn’t your idea of a well-spent winter evening, and yet you’d still like to see or hear an owl in the wild, then there’s another strategy to try. Just before dusk, stand in the parking lot of Sachuest Point National Wildlife Refuge or Third Beach in Middletown or the Moonstone Beach Road side of Trustom Pond National Wildlife Refuge in South Kingstown, and watch for short-eared owls hunting for prey over the adjacent marshlands.
The gold-and-brown streaked birds seldom vocalize, so going after dark won’t be productive. But they are regularly observed at dusk flying back and forth just above the vegetation and occasionally pouncing silently into the reeds to capture a meal. And their long wings and butterfly-like flight are so distinctive that even if you only see their silhouette, you’ll know it’s a short-eared.
A few other owl species can sometimes be detected around Rhode Island this time of year, like tiny saw-whet owls or long-eared owls – and barn owls on Block Island – but finding them is much more challenging. And the noises they make are very un-owl-like.
But if, like me, you want the most owl-like of owl encounters, all it takes is time spent listening in the forest after dark. And plenty of patience.

This story first appeared in The Independent on Feb. 16, 2020.

Friday, February 14, 2020

Drones an important tool in environmental research

            The rapid technological advances in drone technology, together with their affordability and ease of customization, has made them an increasingly important tool for scientists studying wildlife and the environment. Rhode Island researchers are taking advantage of them for such wide-ranging uses as monitoring algae blooms, assessing forest damage following storms, and creating high-resolution maps of the landscape.
            Paolo Stegagno, a new engineering professor at the University of Rhode Island, worries that some people may think that drones are the solution to every problem, and he is skeptical
URI engineer Paolo Stegagno and his drone (Nora Lewis)
that they will be effective at delivering packages or pizzas, as some companies claim.
            “But there are some tasks that drones are really useful for, tasks in which you have to reach someplace that has difficult terrain to go over or could be dangerous for people,” he said. “They can also collect a lot of data that is difficult to collect otherwise, like infrared imagery or thermal information from wildfires or from people in distress. If you select the right sensor for a specific task, you can get a better point of view of what’s going on.”
            Stegagno is working with scientists in three other states to collect data about how algae blooms develop in lakes in an effort to better predict when they might occur. That data will be shared with the Watershed Watch program, which tracks water quality in most of Rhode Island’s water bodies.
            “We don’t really have any real knowledge of what actually triggers the blooms, so we can’t predict them now,” he said. “We plan to put drones in the air and surface vehicles on the water to collect data using specific bands of light to determine the factors driving the blooms.”
            The project will begin this spring by monitoring algae blooms in Barber Pond and Yawgoo Pond in South Kingstown.
            Jason Parent, another new URI professor, is using drones to map forest characteristics like canopy density and tree mortality and to measure stem density and diameter.
            “These are characteristics of a forest that indicate forest health and tree risk to infrastructure, when they’re more vulnerable to failure during storms,” he said. “I’m using that data to help better manage the roadside forest, to reduce risk so we can invest resources in the most beneficial treatments.”
            The objective is to help utility companies and municipalities identify trees that are a threat to power lines and other infrastructure so they may be trimmed or removed before the trees fall. Parent is working with colleagues at the University of Connecticut and Connecticut utilities on a vegetation management program to manage the forest within 100 feet of the roadside by removing unhealthy trees. He hopes to initiate a similar project with National Grid in Rhode Island.
            “It’s an intense program, so it needs to be targeted where it can have the biggest impact, and drones help to identify priority areas,” he said. “Drones are limited by their battery power and other restrictions, so we use them to calibrate data collected by planes. The airborne data has lots of information, but it’s hard to interpret and you can’t get to the same level of detail as you can with drones. So we’re using drones to ground-truth the airborne data.”
            Parent is also beginning a project to use drones to map the inside of buildings to create indoor navigation systems for first responders.
            At the URI Environmental Data Center, which creates ecological maps of the entire state for a wide variety of environmental applications, drones are being used to create high-resolution imagery for use in classifying habitats and land cover.
            “We’re hoping drones will allow us to image over smaller areas and capture much more precise information at times of the year when we can call the shots and not have to wait for the state’s periodic overflights,” said Charles LaBash, director of the center, who notes that the Rhode Island Department of Transportation collects aerial photography of the state by conventional aircraft three times each year to support its stormwater management efforts and other projects. “If something is happening now, we can go up and mobilize relatively quickly. That’s the advantage of drones.”
            For instance, staff at the Environmental Data Center are using drones to monitor the progress of several efforts by the Coastal Resources Management Council, Save the Bay and others to raise the elevation of salt marshes that are threatened by rising sea levels and storm surge.
            “Drones give us a way to monitor the success of the vegetation that’s taking root out there,” LaBash said. “You can look at it with your eyes, but having that imagery gives you a consistent way to document the geospatial position and extent of revegetated areas.”
            When conditions are right, the center is also using drones to look into the water in the state’s coastal ponds to map the location of eelgrass beds. It also has used its drones to test equipment used by other researchers that detects migratory birds flying by the Block Island wind farm, among other projects.
            “There are many other possible uses of drones that we’re just beginning to think about,” said Stegagno, the URI engineering professor, “like monitoring wide areas for early detection of wildfires or for use in precision agriculture, where you collect data from crops to figure out whether your plants are in distress. All you have to do is customize them with the right sensors.”

This article first appeared on EcoRI.org on Feb. 13, 2020/

Wednesday, January 29, 2020

Dead tree brings life to forest

            I knew it was going to happen one day soon.  I just never knew when.  And then finally, sometime during one of last year’s storms, my favorite tree – a massive dead oak in the swampy forested section of my property – went toppling to the ground.
            The tree must have been dead long before I came on the scene.  It was the largest tree on my lot, yet the loggers that came through about 35 years ago didn't want it.  Its enormous trunk was completely stripped of bark, and the last leaves to grow on it became compost decades ago. And yet it still played a significant role in the cycle of life in the forest.
            Woodpeckers visited the naked oak regularly in search of insects boring into its rotted
core.  Hawks occasionally perched on its limbs to scan the area for a meal.  And I sometimes found fur around the lower part of the trunk from where a deer had nuzzled against it, perhaps in an effort to relieve an irritating itch.
            Big dead trees are often cause for alarm among the human population, and many dying trees are quickly dispatched with a chain saw.  Sadly, that was one of the chief reasons for the decline of bluebirds, purple martins and other birds that nest in tree cavities but can’t drill their own holes as woodpeckers do.  Thankfully, we have replaced natural tree cavities with artificial ones – bird houses – so these and other birds can more easily flourish.
            But birds aren't the only creatures that love dead trees.
            The crumbled branches piled around the now-horizontal tree trunk provide protection and nesting sites for small mammals like chipmunks, squirrels, voles and mice.  The entangled branches also make for excellent elevated pathways for these tiny creatures, like a miniature version of a highway on-ramp.
            The increased population of small mammals in and around the fallen oak has attracted predators of a sort I seldom see. 
            I spotted my first least weasel emerging from a tiny crevice beneath the tree last spring.  These fierce relatives of mink are just six or seven inches long – half of it tail – and look cute and cuddly. But they attack and kill prey twice their size with a tremendous bite to the base of the skull.  Despite their ferocious nature, I was pleased that the dead tree had lured such an unusual creature to my yard.
            Foxes and coyotes have nosed around the site, too, now that it harbors so many potential prey species.  And on most spring and summer evenings I can usually hear the back-and-forth hooting of a pair of barred owls that I’m sure are attracted to the feast around the tree.
            Last fall I noticed a bit of moss growing on the fallen trunk, the first step in the long process of decay and decomposition.  But that won't be the end of the tree's contribution to the forest.  Eventually, the rotted wood will deposit its nutrients into the soil and the cycle of growth will begin again.  The nutrient-rich soil will contribute to healthy new vegetation, which in turn will feed other wildlife.  Perhaps a new oak tree will even grow up to take the place of the old one and oversee my back woods.
            For me, though, I'm happy to climb upon the trunk to survey the forest and think back on the many creatures nourished by that old tree over the last century.  I bet it was a satisfying life.  

This article first appeared in the Newport Daily News on January 25, 2020.

Monday, January 27, 2020

Mako shark populations to take half century to recover from overfishing

            An essay in this month’s newsletter of the Rhode Island Saltwater Angler’s Association claims that populations of shortfin mako sharks – a popular sportfish and a tasty offering on local menus – are “in crisis,” with fewer and smaller mako sharks being caught compared to 25 years ago. Written by Long Island attorney Charles Witek, a recreational fisherman who identifies himself as a consultant on fisheries management issues, the essay also criticizes the measures adopted to reduce shark mortality and the long timeline for rebuilding the population.
            “Even if such reductions could be achieved, it will take about 50 years to return the shortfin mako stock to something resembling a healthy level of abundance,” Witek wrote. “Which, in turn, means that I and probably most of the people reading this article, will never see a healthy mako population in our lifetimes.”
            Although shark biologists in southern New England disagree that makos are in crisis,
Short-fin mako shark (Stock)
those surveyed agree that the species is being overfished and that, even if targeted fishing for the species around the world was eliminated entirely, it would likely take at least several decades for the species to recover to healthy levels.
            “In the world of fish, mako sharks are like a Lamborghini or a Corvette or a Ferrari,” said Greg Skomal, a shark researcher and senior scientist at the Massachusetts Division of Marine Fisheries. “It’s a high-performance fish from a physiological point of view. Its body is built for speed, it’s really well adapted to its environment, and it’s a very efficient predator.
            “Those same attributes make it fun to catch for recreational fishermen because they leap out of the water and they’re strong fighters,” he added.
            Last year, the International Commission for the Conservation of Atlantic Tunas, the agency that manages mako sharks in the North Atlantic, concluded that the sharks are being overfished – too many are being killed by commercial and recreational fishermen to sustain the population. The commission recommended two management strategies designed to rebuild the population: Commercial long-line fisheries, few of which target mako sharks, should release any mako that is still alive; and the minimum size limit of sharks captured by recreational fishermen should be increased to 83 inches, which is about the size when they become sexually mature.
            “That translates into fewer dead mako sharks, higher survivorship, and rebuilding of the population,” said Brad Wetherbee, a University of Rhode Island professor who studies mako sharks. “But they realized that it could take until 2070 for mako sharks to rebuild and reach sustainable levels. It’s a slow process.”
It’s a slow process because mako sharks grow slowly, they take a long time to become sexually mature, and they give birth to relatively few young.
            According to Skomal, the United States accounts for only about 10 percent of the landings of mako sharks in the North Atlantic. Most are caught as bycatch by commercial longline fishermen targeting tuna and swordfish. Spain and Portugal have large longline fleets that target mako sharks in the mid-Atlantic, and many other nations primarily catch them as bycatch.
            “We’re small players in the mako market,” he said. “The argument I hear from recreational and commercial fishermen in the U.S. is that we’ve already done a lot for the conservation of makos, and other countries need to step up. But the conservation community says, no, everyone has to pull their weight, which means the U.S. has to reduce its landings further. Some conservation groups are calling for a complete moratorium on mako fishing.”
            That’s not likely to happen, since more than 50 nations fish for mako sharks. And even if targeted fishing for the species is eliminated, mako sharks are still going to be killed unintentionally.
            “If the Portuguese landline fleet targeted only blue sharks, they’re still going to keep catching makos and bring them in if they’re dead,” he said. “There is never hypothetically zero mortality, unless you pull the fleets off the water and reduce fishing effort, and that’s not going to happen. There will always be bycatch mortality, release mortality and illegal mortality.”
            So how did the mako shark population get in such a dire situation in the first place? Skomal said it started with poor historical recordkeeping about shark landings from shark fishing nations, including the United States.
            “We can’t identify a problem if we don’t have good data on which to build a good assessment,” he said. “In the case of sharks, most historical data sets don’t differentiate by species, so it’s difficult to look at historic trends. We also don’t have good reporting from all nations, which means we end up with flawed data. If big fishing nations don’t fully report, then you don’t fully account for all of the mortality.
            “Now that we finally have good data, we suddenly see that we’ve been hitting this species too hard,” Skomal said.
            Wetherbee has been tracking the movements of mako sharks since 2004, and more than 25 percent of the sharks he has affixed with satellite transmitters have been caught and killed by commercial or recreational fishermen. His data, which showed that the mortality rate of mako sharks is more than 10 times higher than the rate previously estimated, contributed to the assessment that the sharks are being overfished.
            “They grow over 10 feet long and over 1,000 pounds, but people hardly ever see makos that big now because there aren’t that many big ones out there anymore,” he said.
            After more than 15 years of studying mako shark movement and migration patterns, their habitat use, fishing mortality and other topics, Wetherbee is pleased that his data is being used to inform policymaking. But he’s not sure the recent policy recommendations go far enough.
            “I have a more radical opinion than most people,” he said. “I don’t think they should catch and kill them at all. But most people aren’t going to subscribe to that. If they were being fished sustainably, I’d say go ahead and catch and eat them.
            “We’ll see if the actions they’ve taken to rebuild the stocks are going to be effective,” Wetherbee added. “It’s a step in the right direction. They could have done more, but they didn’t.”

This article first appeared on EcoRI.org on January 26, 2020.

Thursday, January 16, 2020

Sea urchins could be Rhode Island’s next climate-resilient crop

             Atlantic purple sea urchins are common in coastal waters along the East Coast, and University of Rhode Island scientist Coleen Suckling thinks the Ocean State could become the home of a new industry to raise the spiny marine creatures for consumption in Japan and elsewhere around the world.
                She has teamed with a company called Urchinomics, which is pioneering urchin ranching around the world. Suckling is testing a sea urchin feed the company developed in Norway to see if Rhode Island’s urchins will eat the product and, in turn, become commercially appealing.
                “Sea urchins are generally good at coping with climate change; they appear to be resilient to warming and ocean acidification,” said Suckling, URI assistant professor of sustainable
aquaculture. “So they’re a good species to turn to for commercial harvest. And you can get a good return on your investment from them.”
             The global sea urchin market is valued at about $175 million per year, with about 65 to 70 percent of the harvest being sold to Japan. Urchins are primarily used for sushi, though they are also an ingredient in a variety of other recipes as well.
                Red urchins and Pacific purple urchins are harvested in California, Alaska and British Columbia, while green urchins are captured in Maine and Atlantic Canada. Little is known about how successfully Atlantic purple urchins would compete in the marketplace, but Suckling is taking the first steps to find out.
                The edible part of the sea urchin is its gonad tissue – which chefs refer to as roe or uni and Suckling describes as tasting “like what you imagine a clean ocean smells like” – but the tissue must be firm and bright yellow or orange to get the best prices.
                “Wild urchins typically have small gonads and the color isn’t great, so commercial harvesters are collecting wild-caught urchins and feeding them an enriched finishing diet in cages in the open water for a few months to allow them to grow larger gonads and develop good color,” Suckling said.
                At the Narragansett Bay Campus, URI undergraduates Max Zavell, Anna Byczynski and Alli McKenna are undertaking a three-month food trial on purple urchins caught in Rhode Island waters. The animals are being fed a variety of foods to see how well they grow and if they become marketable. The students monitor water quality and regularly weigh and measure the urchins, and by February they should have preliminary results.
            “If they become marketable, then it opens up a whole interesting range of potential options,” Suckling said. “Under future climate conditions, there may be a need to diversify what we produce in the seafood sector. And since urchins are good at coping with acidification, this could be a good opportunity here in Rhode Island to exploit sea urchins.”
             Even if the formulated diet works as expected, many additional questions remain to be answered before urchins could be raised commercially in the state.
             “It’s a local species, so we can potentially grow them here, but is it something the Coastal Resources Management Council and the Department of Environmental Management would be interested in?” Suckling asked. “Are there aquaculture farmers interested in growing them? Can we ranch them reliably? We’re just taking the first step to see if it’s worth the effort to answer these other questions.
             “Part of my role is to try to understand what seafood we may need to turn to in a sustainable manner so we can maintain food security and economic security in the future,” she added.

Wednesday, January 15, 2020

A tangled knot: Plastics and wildlife

           Almost every day, Geoff Dennis walks the beaches of Little Compton with his dog Koda and picks up the trash he sees along the way. Most of it he discards in a proper trash receptacle, but some of the plastic he finds – bottles, balloons and straws, for instance – is saved and recorded with a photograph at the end of the year to document its annual accumulation.
            In the summer of 2018 alone, he picked up 2,946 plastic bottles, 129 cigarette lighters, and 529 straws on just one beach. And that’s just the trash he counted and photographed. He picked up many many more plastic cups and plates, Styrofoam take-out containers, plastic bags, and an untold number of other plastic items. One day last May he collected 282 balloons on the beaches he frequents, and two weeks later he picked up another 89. This year he noted
Koda and balloons collected on RI beaches (Geoff Dennis)
the growing number of plastic pods from Keurig coffee makers, and blue rubber gloves are on the rise as well – 70 one day in September and 30 more three weeks later.
            “They’re small, as some people say in defending the use of plastic straws, but still part of the plastic problem,” said Dennis. “Smalls add up.”
            He estimates that about half of what he picks up is generated by local beachgoers and the other half from people and industries many miles away, since it shows evidence of having drifted on ocean currents for some time.
The growing problem of plastics pollution is due in part to our throw-away society and because plastic degrades very slowly in the environment. It persists for hundreds of years, at least. And unless we change our consumer behaviors and the plastics and packaging industries reform themselves, the problem won’t go away anytime soon. The recycling rate of plastics is floundering at dreadfully low levels while plastics production is expected to increase by about 40 percent by 2025.
“Plastic pollution has been an issue for Audubon for a long time, largely because of its impacts on wildlife,” said Meg Kerr, Audubon’s senior director for policy. “The global focus on plastics in the oceans and the attention it has received through social media has made it an issue of top concern to us. And in the context of climate change, plastics are made by fossil fuels, which we are trying to transition away from.
“Our throw-away society wasn’t created by accident,” she added. “It’s a very intentional industry push to create a throw-away world so the industry has a use for its products. They greenwash the ability to recycle and reuse, knowing full well that only a small portion actually gets recycled or reused.”
Jamie Rhodes agrees. A Providence-based attorney who has been working on plastics reduction initiatives around the country for the last decade, he said that consumer product manufacturers and those who use plastic for packaging and shipping have no incentive to reduce their use of plastics because it costs so little and its creation is subsidized by the oil industry.
The plastics industry emerged after World War II as the oil industry sought uses for the byproducts of the process of refining crude oil into gasoline and other fuels.
“They realized that the chemicals that came from the fossil fuel refinement process could be turned into plastics, which are among the most flexible chemical compounds out there,” Rhodes said. “The growth of plastics was a way for the fossil fuel industry to find value in what had been an industrial byproduct. They were drilling for oil, and plastics became a byproduct.
“Now we’re at the point where the tail is wagging the dog,” he continued. “Our use of oil for transportation and heating is declining, and a lot of the large fossil fuel companies have realized that the future of oil extraction is in plastics. There has been a significant shift in oil extraction efforts to cater to the needs of the plastics industry. We’re now seeing a growth in the construction of cracking plants in the U.S., which crack the chemical chain into component parts for specialized plastic resins.”
The results of all of that plastic production can be seen everywhere you look.
Approximately 8.3 billion tons of plastic has been produced since the 1950s, and only about 9 percent has been recycled. Drink companies alone use about 500 billion single-use plastic bottles each year. Much of it finds its way into the oceans and across the landscape where it affects wildlife of every sort.
According to a 2016 report by the United Nations, more than 800 species have been harmed by marine debris, mostly through ingesting or becoming entangled in plastics, which causes suffocation, starvation and drowning. As many as 40 percent of cetaceans and 44 percent of seabird species have been documented to have ingested marine debris.
Because plastic floats, small pieces are often accidentally consumed by seabirds, which may be the most likely wildlife to be harmed by plastic. University of Rhode Island Professor Peter Paton said the “classic example” is the laysan and black-footed albatrosses on Midway Island in the Pacific, which soar for thousands of miles around the ocean in search of food and often bring pieces of plastic back to their nests to feed their chicks, sometimes pieces as large as toothbrushes.
“If you go to Midway, you see dead chicks everywhere with their crops and gizzards completely full of plastic,” said Paton, a member of the Audubon board of directors.
Closer to home, an ongoing study of chemical contaminants in the tissues of great shearwaters off the New England coast by a URI doctoral student turned into a study of plastics after she found plastic inside every one of the 350 dead birds on which she conducted a necropsy (an animal autopsy).
“It’s been quite jarring,” said Anna Robuck, who examined birds that were found dead between 2007 and 2019. “There hasn’t been a bird I’ve cut open that hasn’t had plastic in it. I’ve analyzed about 400 pieces of the plastics I found in the birds, and most are recyclable polyethylene.”
Among the plastics Robuck has found in great shearwaters are fragments of bottle caps, food wrappers and tangled up balls of microfibers. Most are smaller than 5 millimeters in size, which are considered microplastics, though many are considerably larger, large enough to pose a choking hazard. Some birds were found to have more than 100 pieces of plastic in their bodies, but they averaged 7 to 10.
“Great shearwaters are opportunistic foragers at the water’s surface, which means they’re probably ingesting the plastic directly,” she explained. “Most pieces are large enough that their prey – primarily small fish called sand lance – didn’t consume it first.”
While it is uncertain if the ingestion of plastic was the primary cause of death of the birds, it is likely to have been a contributing factor. And because chemical contaminants easily adhere to plastics, the plastics may also serve to deliver toxic chemicals to the birds and other animals that ingest them.
Not all plastics are equally hazardous when consumed by wildlife, however. Balloons are especially deadly.
A study published last summer by researchers in Australia found that balloons are more likely to kill seabirds than any other kind of plastic debris. In an evaluation of 1,733 dead seabirds, the researchers noted that 32 percent had ingested plastic debris. And while soft plastics like balloons accounted for only 5 percent of the items ingested, they were responsible for 42 percent of the seabird deaths. In addition, although just 2 percent of all ingested plastic were pieces of balloons, the birds that ingested balloon pieces were 32 times more likely to die than if the bird had ingested a hard plastic. According to the research team, balloons are especially lethal because they are easily swallowed and can squeeze into a bird’s stomach cavity, where they reduce the space available for food.
But pelagic seabirds aren’t the only birds negatively affected by plastic pollution.
Paton said that gulls often include a wide variety of plastic debris in the construction of their nests, some of which pose an entanglement threat to the birds and their chicks.
“Leg injuries in gulls and shorebirds are common due to entanglements,” he said. “One of the first piping plovers I caught for my research had fishing line entangled around one foot and the leg was swollen. It causes them to have a hard time foraging, and they often lose their leg because of it.”
It’s not just coastal birds that are at risk, however. Paton received a call in September about a great blue heron in Burrillville whose neck and wing were entangled in plastic debris, making the bird unable to fly.
Examples abound of marine mammals and sea turtles being similarly affected by plastic pollution in the marine environment. A Cuvier’s beaked whale died on the coast of the Philippines last spring with 88 pounds of plastic in its stomach. A month later, a pregnant sperm whale in the Mediterranean Sea was found dead after having swallowed 48 pounds of plastic. Then there’s the harp seal found dead in Scotland with plastic wrappers in its intestines and the viral photo of the sea turtle with a plastic straw stuck in its nostril.
“When baleen whales feed, they aren’t selectively nibbling on their very tiny prey. They swim across the water with their mouths open, and they take in a lot of water and whatever else happens to be in the water,” said Janelle Shuh, the stranding coordinator at Mystic Aquarium. “When they filter the water out with their baleen, any plastics in the water get stuck inside their mouths.”
Shuh calls ocean plastics a significant problem for all species living in the ocean environment, and it’s a problem she sees regularly in the animals she rescues from beaches throughout the region. She regularly responds to calls about seals entangled in monofilament fishing line and other plastic debris, which often causes wounds and infections. She once conducted a necropsy on a dead harp seal and found several plastic bags in its stomach.
“I’ve also done plenty of sea turtle necropsies where we’ve seen plastics in their stomach and esophagus,” she said. “Leatherback turtles eat jellyfish, and a floating plastic bag can have the appearance of a jellyfish and they’ll eat it assuming it’s prey. Loggerheads also tend to have had plastics in their system. They munch on crabs on the sea bottom, and if there’s a plastic bottle cap down there, they might accidentally ingest it along with the crab.”
While it’s often difficult to determine whether the plastic items were the primary cause of death of the animals, Shuh believes the plastic is usually a contributing factor.
“Our narrative needs to shift,” she concluded. “I grew up in the 70s with the mantra of ‘reduce, reuse, recycle.’ But we’ve only really focused on recycling, and that’s becoming more challenging. We need to shift our mindset to ‘reduce and reuse’ so the materials aren’t getting into the environment in the first place. That’s the direction we need to go in now.”

This story first appeared in the December 2019 issue of Audubon Report.