Tuesday, December 26, 2017

Forest birds decline in Vermont

In one of the longest-running studies of its kind in North America, the Vermont Center for Ecostudies has documented a 14.2 percent decrease in forest birds in Vermont over the past 25 years. While not all of the 125 species included in the report are declining – and some are even increasing – the researchers say that the overall state of forest birds in the region raises critical concerns about birds and forests alike.
            Unlike the North American Breeding Bird Survey, which has conducted an annual assessment of bird populations along roadsides since 1966, the Vermont study provides data about birds in interior forests away from the effects of roads.
            “Forests are vital to our economy in Vermont, and birds are vital to the health of the
Canada warbler (Garth McElroy)
forest,” said biologist Steve Faccio, the lead author of the report. “This should serve as a wake-up call to focus our efforts on maintaining healthy forests and thinking about how we should do that.”
            The study used highly-skilled birders who traveled 31 forested transects twice during each breeding season and counted all of the birds they saw or heard at five sites along each transect. Most of the population declines they observed occurred during the first ten years of the study. After stabilizing for about a decade, bird numbers began decreasing again in 2008.
            An in-depth analysis of 34 of the most widely distributed species found that 13 have experienced significant declines, including Canada warbler, white-throated sparrow, great crested flycatcher and veery. Populations of just eight species have increased, among them American robin, red-eyed vireo and ovenbird.
            Faccio said that forest fragmentation, climate change, invasive species and threats on the birds’ wintering grounds could all be contributing factors to their decline. “Just because we’re seeing lower populations here doesn’t necessarily mean it’s something happening on the breeding grounds that’s causing the decline,” he said.
            Changes in habitat due to maturing forests could explain some of the declines. Habitat for species that nest or feed in the lower or middle canopy layers, for instance, could be affected through the natural progression of forest growth.
The birds that fared the worst in the study are the “aerial insectivores,” those that catch and eat insects on the wing, such as Eastern phoebe, Eastern wood pewee and least flycatcher.  The 11 species in this group declined by 45 percent.
            “That leads us to believe that there’s something going on with their prey, probably a combination of effects like pesticide use, changing climate and habitat,” Faccio said. “Polarized light pollution is having a devastating effect on broad groups of insects, which could lead to reproductive failure of some water-breeding insects.”
            The report recommends that those interested in managing their forests for birds should consider creating more structural diversity to emulate natural disturbances in mature forests, while also retaining a high proportion of large trees to support canopy and cavity nesters. Land managers should also focus on protecting uncommon forest types, contiguous forest blocks of more than 250 acres, and corridors that connect conservation areas.

This article first appeared in the fall 2017 issue of Northern Woodlands magazine.

Friday, December 22, 2017

Roasting chestnuts may make a comeback

It’s been about a century since Americans have been able to celebrate the holidays by roasting native chestnuts over an open fire. Almost every one of America’s more than 4 billion chestnut trees from Maine to Georgia was wiped out by chestnut blight, a fungal disease that spread like wildfire after its accidental introduction into the U.S. from trees imported from Japan to the Bronx Zoo in 1904.
The tree’s disappearance has dramatically changed the landscape of eastern North America. Chestnuts were once the dominant tree in eastern forests, and its wood was used for fence posts, railroad ties, utility poles and anything else that required rot-resistant lumber.
American chestnut tree, via The Rural Blog
Many of Rhode Island’s historic homes were once sheathed in it.
In addition, the edible nuts provided vital nutrition to wildlife and were an important element in cattle and hog feed. And because the nuts ripened right around Thanksgiving, they became a popular snack during the holiday season (and a key lyric in that most popular of Christmas carols).
All but the caroling ended soon after the blight took hold. The few chestnuts we eat these days come from non-native species imported from overseas.
But that may not be the case in the coming years, thanks largely to efforts by the American Chestnut Foundation and a little help from local volunteers. A number of research projects are underway designed to develop blight-resistant trees so the species can be restored in our forests.
URI Master Gardener Rudi Hempe is one of the volunteers. He and a team of about 25 other master gardeners who call themselves Rudi’s Rangers are growing a one-acre breeding orchard and a two-acre seeding orchard of chestnut trees on land owned by the South Kingstown Land Trust.
The trees they planted originated with seeds from a single tree in East Greenwich and another one in Exeter that apparently have a genetic abnormality that makes them immune to the blight. Those two parent trees are among the very few mature American chestnuts that did not succumb to the disease, and they are giving scientists a starting point for studying disease resistance.
When the trees planted and maintained by the master gardeners grow tall enough, Rudi’s Rangers will inoculate them with a low-dose of the blight in hopes that some will develop a resistance to the disease. Similar efforts are underway at three other locations in Rhode Island and at dozens more in Massachusetts, Maine and elsewhere in the tree’s original range.
In a separate study, the chestnut foundation is also crossing American chestnuts with a similar species from China that is naturally resistant to the disease. Five of those hybrid trees were planted at URI’s East Farm several years ago, and three of them are still going strong.
It is uncertain whether any of these studies – or others approaching the problem using biotechnology tools – will bear fruit. It’s likely to take a decade or more to find out. But we’ve waited far longer than that already. The wild trees have been gone for so long that almost no one alive today has any recollection of how stately a chestnut forest looked before the blight.
But hopefully, in the not too distant future, singing about roasting chestnuts will have a new, deeper meaning to carolers – and all Americans – once the majestic trees make their heralded return.

This article first appeared in the Independent on December 21, 2017. 

Saturday, December 16, 2017

A merry year for Christmas tree growers

            Jean Bento knows that the weather is the primary factor determining the success or failure of local Christmas tree farms. As the owner of Patchet Brook Tree Farm in Tiverton, she’s happy to report that the weather in 2017 has been ideal.
            “The weather affects almost everything about this business,” she said.
            Bento explained that the rainy spring came along at just the right time to stimulate growth and keep newly-planted seedlings alive, but there wasn’t so much rain that it caused a fungus to build up on the needles. The summer wasn’t hot enough to dry out the trees or make the needles susceptible to dropping too soon. And the weather on Thanksgiving weekend – the first big weekend for sales – was perfect for families to visit local Christmas tree farms and tag or cut their trees.
            “It’s definitely been a good year for growing Christmas trees,” agreed Eric Watne, owner of Clark’s Christmas Tree Farm in Tiverton and president of the Rhode Island Christmas Tree Growers Association. “Rain in spring is key, but you also need some rain in the summer, too. When fir trees think they’re going to die, which will happen when we don’t get rain in the summer, they start producing pine cones, which is their way of propagating the species. That’s bad for Christmas trees because the tree’s nutrients go to the cones and the needles die.”
            That didn’t happen this year.
It also wasn’t a bad year for pests, according to University of Rhode Island entomologist Heather Faubert, despite concerns that gypsy moth caterpillars were going to feast on the needles.
“The gypsy moths didn’t turn out to be as bad as we feared,” she said. “Spider mites and scale insects are the other pests that can be a concern for Christmas tree growers. A few aren’t a problem, but if you get high numbers of them, the trees lose their color and the needles start to drop.”
            The conditions were so good this year, in fact, that the growers said that any trees negatively affected by last year’s drought have probably recovered.
            The only concerns Christmas tree farmers face this year have to do with competition from artificial trees, which have improved in appearance in recent years, and from the big box stores and street-corner sellers that typically get their trees from Quebec or Nova Scotia, where they are cut down as early as October.
            Jan Eckhart, owner of Sweet Berry Farm in Middletown, isn’t worried. He said nothing can compare to locally grown trees. And besides, “Christmas trees are a renewable resource. It’s like growing broccoli. The freshest you can possibly get is a farm grown tree from right here in Rhode Island.”
            While the window for selling Christmas trees is condensed into a few busy weeks, the growers agree that it’s their favorite time of year.
            “When people start showing up to buy their trees, they’re in such a great mood,” said Watne. “I get to be a little part of everybody’s Christmas. It’s a month-long Christmas party.”

This article first appeared in the Newport Mercury on December 14, 2017.

Thursday, December 14, 2017

Forecast calls for a snowy owl winter

            It’s looking more and more like the winter of 2017-18 is going to be a big year for snowy owls in southern New England. Large numbers of the iconic white birds have been observed throughout the Upper Midwest and Northeast since late November, and many have turned up in Rhode Island.
            Project SNOWstorm, a volunteer-based snowy owl tracking organization, is predicting that the attractive birds will invade much of the northern tier of the United States this winter. Hundreds of birds have already been sighted, including some as far south as North Carolina, Oklahoma and Missouri.
            Scott Wiedensaul, director of Project SNOWstorm, said it’s difficult to predict how many birds will travel to the area or how long they will stay. “There’s a little bit of voodoo and black magic in all of this,” he told Audubon magazine. But the signs point to it being a good year for snowy owl watching.
            Rhode Island has so far had visits by at least 17 snowy owls in recent weeks, according to Rachel Farrell, a member of the state’s Avian Records Committee. University of Rhode Island ornithologist Peter Paton reported seeing seven snowy owls on Block Island last week, and local birdwatchers have reported additional owls at Sachuest Point National Wildlife Refuge in Middletown, East Matunuck State Beach in South Kingstown, along the shores of the Narrow River in Narragansett, and elsewhere. One was even photographed perched on a chimney in a residential neighborhood in Providence, and another Providence bird – or perhaps the same one – was located at the headquarters of Save the Bay.
Just one or two snowy owls usually visit Rhode Island during a typical winter.
Snowy owls spend most of their lives in the Arctic feeding on lemmings on the tundra. But Farrell said that about every four years, when lemming numbers are high, the owls lay more eggs than usual. Many of the birds that hatch from those eggs end up migrating south in winter after being forced from their Arctic habitat by adult owls due to the reduced availability of food in the deep snow.
“It’s all due to the population cycling of lemmings,” she said. “They’re a boom or bust animal.”
Canadian scientists reported that snowy owls successfully raised an especially large number of young birds last summer.
This year’s irruption of snowy owls into the U.S. is not unprecedented. Four years ago, the the country experienced the largest influx of snowy owls since at least the 1920s, when several thousand owls spent the winter south of the Canadian border. Some traveled to places they had never before been reported, including Jacksonville, Fla., and Bermuda. More than 400 were observed in Pennsylvania alone, a state that seldom records more than 10 in a year.
            The birds that visit Rhode Island are usually found on beaches, farm fields and airports, which mimic their tundra homes, where they search for mice and voles. Owls that spend time in coastal locations often hunt for wintering ducks, something they don’t often eat on their breeding grounds.
            As exciting as it is to see a snowy owl, they can also be a nuisance and a safety hazard at airports. Paton and fellow URI professor Scott McWilliams will attempt to capture and relocate any owls that show up at Quonset State Airport and other undesirable locations this winter.
            The large number of snowy owls visiting the area is not necessarily a sign that the breeding population is growing, however. Farrell said that the population of snowy owls breeding in North America has declined by about 64 percent since 1970, though scientists are not sure why.
Unlike so many other rare birds that occasionally turn up in southern New England, snowy owls are easy to identify. Weighing in at about six pounds, it is the heaviest owl species in North America, and its white plumage and piercing yellow eyes make it unmistakable. Adult males may be pure white, the perfect camouflage for a bird that spends much of its life in a snowy environment. Younger birds are much more visible, with contrasting gray barring on their white bellies and wings that make them stand out as they perch on fence posts, beaches and snow-covered fields.
The Audubon Society of Rhode Island advises that those interested in going in search of snowy owls in the area should bring along binoculars or a spotting scope and stay at least 200 feet away from the birds, as the owls can be skittish. It also recommends staying quiet and refraining from making sudden movements that may frighten them. The owls are already rather stressed after their long migration and their efforts to find food in unfamiliar places, and rambunctious humans will add to their stress.
            “We still don’t know the magnitude of this year’s irruption yet,” concluded Farrell. “But it has already been fairly substantial. And it started a little earlier than the last one, so that may be a good sign for what’s to come.”

This story first appeared on EcoRI.org on December 14, 2017.

Monday, December 11, 2017

Changes to ecology of Narragansett Bay worry fishermen

            Narragansett Bay has experienced dramatic changes over the last century, from being a dumping place for sewage and industrial pollutants to a near paradise for recreational swimming and boating. But changes continue to occur, whether from the warming climate, invasive species, fluctuating wastewater effluent or other factors.
            As University of Rhode Island oceanography professor Candace Oviatt told an audience of fishermen, scientists and students last week, “I don’t think I’ve ever seen an average day on Narragansett Bay. The bay is always changing. Every year is different. Whether we like it or not, the bay is going to keep changing.”
            Oviatt’s comments were part of a daylong symposium sponsored by Rhode Island Sea Grant aimed at creating a dialogue between fishermen – many of whom are worried that the
Narragansett Bay photo by Frank Carini/EcoRI News
bay has gotten so clean that there is little food left for fish to eat – and scientists whose research tells a sometimes confusing story of how the changing bay ecology might give that erroneous impression.
            While most of the scientists claim that their research suggests that the biomass of fish and other creatures living in Narragansett Bay has changed little through the years, almost all said the composition of species that call the bay home has changed dramatically.
            A weekly fish trawl survey in two locations in the bay conducted since 1959 illustrates those changes. According to Jeremy Collie, the URI oceanography professor who directs the trawl, in the early years of the survey most of the species collected in the nets were fish and invertebrates that live on or near the bottom, like lobster, winter flounder, tautog, cunner and hake. Those species also happen to prefer cooler water.
            In recent years, the species that prefer warmer waters and that live higher in the water column have dominated the trawl survey results, including butterfish, scup and squid.
            “Very few species are standing still or swimming in place,” said Collie, noting that similar patterns have taken place in estuaries throughout the Northeast. “All are either increasing or decreasing. And some have had really big changes.”
            One of the major drivers of change in the bay is nutrient levels, primarily nitrogen and phosphorous, which largely come from discharges from wastewater treatment plants. Those nutrients stimulate the growth of plankton, which are fed upon by fish and a wide variety of marine invertebrates. But when nutrient levels are too high, it can cause harmful algae blooms and oxygen depletion in the water, which can lead to massive fish kills like the one that occurred in Greenwich Bay in 2003.
            Stricter discharge regulations for wastewater treatment plants since the mid-2000s has reduced nutrient levels significantly, leading to much clearer and cleaner water, especially in the upper bay. But it has prompted some fishermen, including lobsterman Al Eagles, to worry that Narragansett Bay has become “a dead bay.” Their concerns are in part because the decline of popular species like winter flounder and lobster seemed to occur at the same time that discharge regulations were tightened.
            Oviatt acknowledged that nutrient levels in the upper bay have declined by 50 percent since 2004, which resulted in a 33 percent decrease in “primary production” – the growth of plankton, especially algae. This has significantly decreased the size of the annual winter/spring plankton bloom that occurs throughout the bay and serves as the base of the food web, when it sinks to the bottom and is fed upon by crabs, fish and other species.
            “When we have a short winter/spring bloom, or no bloom, we have low input of organic matter to the sea floor,” Oviatt said. “The consequence is lower biomass to the benthos [seafloor] and pelagic fish dominating the bay.”
            She said this partly explains Collie’s findings that the species composition in the bay has shifted from bottom species to species living higher in the water column.
            “Are there fewer fish in the bay? I don’t think so,” she said. “We’ve had a dramatic decrease in the bottom community, which started in the 1990s. Our decapods [crustaceans like lobsters and crabs] have basically left the bay.”
            Oviatt said that nutrients in the bay are still three times higher than they were before Europeans colonized New England, but just a few decades ago, when more sewage was being discharged into local waters, nutrient levels were up to five times higher than in pre-colonial times.
            “Wastewater treatment facilities are still the major contributor of nutrients to the bay,” she said.
            Yet Oviatt and others said that decreases in nutrients from wastewater plants aren’t the only reason for the changes to marine life in Narragansett Bay.
            Robinson Fulweiler, a professor at Boston University who studies nutrients in the bay, said that the warming climate is causing some species to move northward to cooler waters and other species to arrive here from the south. And other factors complicate the situation.
            Responding to a question about the “best” level of nutrients in the bay, she said it depends on what you’re looking for. “The estuary a purist wants to go back to is not likely the one that fishermen might want.”

This article first appeared on EcoRI.org on December 10, 2017.

Sunday, December 10, 2017

Spotted turtles in trouble in Rhode Island

            A University of Rhode Island doctoral student who surveyed the state for freshwater turtles and studied their habitat preferences found that the once-common spotted turtle is in trouble, due largely to habitat disturbance.
            Scott Buchanan, a New Jersey native working in collaboration with URI Associate Professor Nancy Karraker, repeatedly visited 88 different wetlands in the state over three years and captured nearly 2,000 turtles of four different species. Just 50 were spotted turtles, a species considered by the state to be of high conservation concern and a candidate for the U.S. endangered species list.
            “Throughout their range, populations of spotted turtles have declined extensively, and we can certainly say with a good deal of confidence that’s also the case in Rhode Island,” said
Spotted turtle (Photo by Scott Buchanan)
Buchanan, who graduates from URI later this month. “I found that they are associated with wetlands in forested landscapes, which means they are susceptible to development, forest fragmentation, wetland alteration and other human disturbances.”
            Buchanan said that the largest populations of spotted turtles he found were in locations where human disturbance has been minimal. “So now it’s a matter of managing those landscapes in an appropriate way,” he added.
            Habitat alteration is not the only conservation concern the species faces, however. The illegal collection of wild turtles for the pet trade is also a problem.
            “Spotted turtles will command a formidable sum in the pet trade, which is unfortunate,” Buchanan said, noting that he encountered people during his research who had captured spotted turtles they intended to bring home to keep as pets but released them at his insistence. “It’s really easy for someone to deplete an entire population of them very quickly.”
During his turtle surveys, Buchanan also found a non-native turtle called a red-eared slider in more wetlands than he found spotted turtles. The slider is a species commonly purchased at pet stores and frequently released into the wild after their owners no longer wish to care for them. He said that wetlands close to human populations, especially those with easy access from roads, are the most likely place to find red-eared sliders in Rhode Island.
“They’re an especially detrimental invasive species,” he said. “It’s a good bet that all the sliders we found are turtles that were bought at pet stores. We don’t know if they’re reproducing in the wild.”
Eastern painted turtles and common snapping turtles, the two most common species of freshwater turtles in Rhode Island, were found in abundance during Buchanan’s turtle surveys.
“They were everywhere, with no strong pattern as to where we might find them across different landscape types,” he said.
What can be done to protect the region’s declining spotted turtle populations?
“It would mean protecting and preserving wetlands, especially forested wetlands, including small wetlands like vernal pools where they sometimes overwinter,” Buchanan said. “It would also mean minimizing fragmentation of the landscape surrounding those wetlands. And it’s also really important that we protect the turtles themselves from illegal collection. That’s an increasing concern among conservation biologists.”
As Buchanan prepares to graduate from URI, he will share his data with a region-wide team of biologists collecting information about the three turtle species being considered for inclusion on the U.S. endangered species list – spotted, wood and Blanding’s turtle.
“The habitat information we collected could help determine where populations of spotted turtles occur and help protect and appropriately manage those populations into the future,” he said.

Friday, December 8, 2017

What do plants hear?

            Plants and trees are seldom considered to have acute senses – at least not like those of many mammals. But scientists at the University of Western Australia discovered that plants have far more complex senses than previously believed, and they can even detect and respond to the sound of moving water.
            In a study led by Associate Professor Monica Gagliano, pea plants sensed sound vibrations from running water moving through pipes or in the soil, and the plant’s roots responded to that sound by moving toward the source of water. The study also revealed that plants avoid other sounds by moving away from them.
            The researchers put pea plants into containers with two tubes at the base, giving them a choice of directions for their roots to grow. They then exposed the plants to a series of sounds beneath each tube, including white noise, running water, and a recording of running water.  They found that the plants could tell where the source of the water was and their roots grew toward the water.
            “It was surprising and extraordinary to see that the plant could actually tell when the sound of running water was a recording and when it was real, and that the plant did not like the recorded sound,” said Gagliano, adding that when moisture was readily available in the soil, the plants did not respond to the sound of running water.
How the plants accomplish this feat is unknown. “The detection of acoustic vibrations, which are vibrations of mechanical nature, is likely to involve the same sensory systems plants use to detect touch – and they’re really good at that,” she said. “If correct, this would possibly involve touch genes and mechanoreceptors because sound is a touch-at-a-distance kind of phenomenon.”
These findings may explain how and why tree roots invade sewer pipes and could lead to the development of soundproof materials for pipelines.
“This would not only improve the sewer systems but reduce exorbitant repair and maintenance costs to municipalities worldwide and make the use of toxic chemicals currently used to clear the roots from the sewer system unnecessary, hence reducing environmental pollution and contamination,” Gagliano said.
The study also raises questions about the implications of noise pollution on plants. Might the increasingly noisy environment be drowning out the ability of plants to hear moving water? Gagliano calls that an open question that should be investigated.
“In animal communities, both in terrestrial and marine environments, these kinds of questions have been raised and the current available studies are showing that these effects are indeed serious and detrimental,” she said. “Based on our findings, it is reasonable to expect that this would be the case for plants, too. Acoustic pollution could mask important acoustic information and make life and survival for plants more difficult. And we have no idea of the long-term consequences of this form of anthropogenic disturbance to plant life.” 

This article first appeared in the fall 2017 issue of Northern Woodlands magazine.

Tuesday, November 28, 2017

It's bug versus bug in fight against invasive species

            The mixed hardwood forest on the edge of the town of Dalton in western Massachusetts looks healthy to the untrained eye, but the researchers from the University of Massachusetts who visited the site every few weeks last summer are anything but untrained. They quickly noted the small holes made in some trunks by foraging woodpeckers and distinguished them from the even smaller holes made by wood-boring insects. And staring into the canopy they observed that many of the trees were in the early stages of decline.
Consisting primarily of ash and red maples, the forest is owned by the nearby city of Pittsfield to protect its public drinking water supply. But it also serves as a living laboratory to test a variety of methods for controlling the emerald ash borer, an iridescent green beetle native to China that has killed hundreds of millions of ash trees in the eastern and central United States, Ontario and Quebec.
The invasive beetle was discovered near Detroit in 2002 and slowly expanded in all directions, reaching New York in 2008, Massachusetts in 2012 and New Hampshire a year later.
Spathius galinae, a parasitoid of emerald ash borer. (Jian Duan USDA)
While it hasn’t yet been found in Vermont or Maine, it is only a matter of time before trees there will also start dying. The beetle is expected to kill almost all mature ash trees in the region in the next decade or two.
But that isn’t stopping researchers from trying to control the invasive beetle and find a way to protect future generations of the trees from succumbing. While several trees in the Dalton forest have been injected with a systemic pesticide to test whether adjacent trees will benefit from the treatment, the forest is primarily the site of a series of biological control experiments to determine if the emerald ash borer’s natural enemies in the Far East might succeed at keeping the insect in check here as well.
As UMass research fellow Ryan Crandall wandered the forest, he carried with him two prescription medicine bottles capped with a fine mesh. Inside the bottles were coffee filters embedded with emerald ash borer eggs, and inside the eggs were the larvae of Oobius agrili, a tiny parasitic wasp that is one of several insects that scientists hope will do in the U.S. what they do in China – control emerald ash borer populations so native ash trees can continue to thrive.
Crandall and his assistant, Sebastian Harris, were seeking the perfect trees on which to hang the medicine bottles – ash trees that aren’t too far gone yet but that exhibit numerous woodpecker holes suggesting the trees are infested with emerald ash borers. Most of the larger trees they examined were already near death, but eventually the researchers selected a couple of smaller specimens and proceeded to hammer nails in their trunks and hang the pill bottles on the nails. Soon, they hoped, the parasitic wasps would emerge and seek out more emerald ash borer eggs in which to lay their own eggs.
Although Crandall and Harris spent just 30 minutes at the Dalton site, they were far from finished for the day. They had five more stops to make at similarly infested forests in Massachusetts, New York and Connecticut, where they left behind a total of 1,400 emerald ash borer eggs parasitized by Oobius agrili....

Continue reading the rest of this article in the fall 2017 edition of Northern Woodlands magazine.

Wednesday, November 22, 2017

Nocturnal feeder visitors

            Before construction was even finished on my house many years ago, I had already put up several birdfeeders in the backyard, and I’ve been keeping them filled throughout the colder months of the year ever since. If you haven’t put out your feeder for the year yet, it’s definitely time. In addition to the regular winter visitors, I have high hopes that this will be one of those unusual years when we’ll have some rarities from the far north dropping by, like redpolls, evening grosbeaks and red crossbills.
            But don’t think that it’s just birds and squirrels that are attracted to birdfeeders. A wide variety of other creatures are, too. And if you get into the habit – as I have – of briefly turning on
the back porchlight and glancing at the feeders before going to bed at night, there is an excellent chance that you will spy some unexpected neighbors dropping by for a bedtime snack.
            I first started paying attention to my nocturnal feeder visitors when I noticed that large
Cartoon by David Chatowsky
quantities of birdseed was disappearing during the overnight hours when I assumed all the seed-eating birds were asleep. It wasn’t long before I discovered a parade of wildlife scavenging spilled seed from beneath the feeders and a few adept critters climbing on the feeders and knocking more seed to the ground.
            A pair of gray foxes were the first night-time animals I noticed in the illuminated area around my feeders. Slightly larger than their more common red cousins, gray foxes sport a conspicuous black tip to their tail and a black “mane” running atop their tail’s entire length. When I turned on the light, they glanced toward it and then went back to slurping up sunflower seeds from the ground.
            My continued vigilance with the backyard light occasionally turns up at least two different striped skunks that must live nearby, one with a wide white stripe down its back and tail and another whose white stripe is thin, crooked and mottled with black. In all my years of watching, I’ve seen just one opossum, and it just strolled through the light without stopping to eat any seeds.
            My favorite nighttime visitors have been flying squirrels, three of them with big ears, huge eyes and a thick flap of fur between their front and hind legs allowing them to soar from tree to tree. They frequently chase each other around the feeders and then play peek-a-boo behind a tree trunk when they see my face in the window. Like several of the more common daytime birds, the flying squirrels take one seed at a time and disappear into the forest to eat it before returning for another morsel.
            Lately, my feeders have been regularly assaulted by a family of five raccoons. When I flicked on the light the other night, I saw one tugging at a big chunk of suet, another was hanging upside-down on a tube feeder sucking out the seeds, and a third was on the ground gobbling up what the tube sucker had spilled. The other two animals were perched comfortably above the feeders high in a tree, probably digesting a big meal compliments of yours truly.
            But I’m not complaining. My nocturnal visitors are highly entertaining, and I’m happy to have them. Besides, it could be worse. At least no bears have found my feeders. Yet.

This article first appeared in The Independent on November 16, 2017.

Thursday, November 16, 2017

Scientists seeking insights into saw-whet owl migration

Nearly every evening between mid-October and Thanksgiving, when the weather conditions are promising for bird migration, Scott Comings sets up a series of nearly-invisible nets on Block Island and plays a recording of the call of the saw-whet owl, the smallest owl to be found in Rhode Island. His aim is to capture as many of the birds as possible, place bands around their legs, and learn what he can about the migratory habits of the diminutive owl.
            Comings, the associate director of the Rhode Island office of The Nature Conservancy, is among a growing cadre of biologists and ornithologists from throughout the coumtry who have been banding saw-whet owls regularly since the early 2000s to get an idea of the bird’s
Saw-whet owl (Megan Lorenz)
movement patterns and population distribution. The effort, dubbed Project OwlNet, began in Pennsylvania in 1997 and now includes several hundred researchers at more than 350 different sites.
            “Before this started, there was a big question about how they move through the area, so it became a concerted effort to see if we could crack this problem,” said Comings, who calls the birds “a really majestic species” despite being just 8 inches tall. “It’s a species that has always captivated me. It’s something you don’t normally see, so that pushes me to want to do more, to learn more, and to go deep into the night trying to catch them instead of sleeping.”
            Peter Paton, professor of natural resources science at the University of Rhode Island, is another of the Project OwlNet collaborators. He has been banding saw-whet owls since 2000 at locations in Richmond, South Kingstown and Hope Valley.
            “It’s as effective to set up the nets at my house as it is at more remote areas,” he said. “It turns out you can put a net out almost anywhere and still do a good job of catching the birds.”
            In a typical year, he catches more than 100 owls, and some nights when the winds are just right, he may catch a dozen or more in just a few hours. Comings catches similar numbers of owls, though one year he banded more than 200 of the birds.
            In the eastern United States, saw-whet owls primarily breed in northern New England and New York and in the Appalachian Mountains, and they winter as far south as North Carolina. According to Rachel Farrell, a member of the Rhode Island Avian Records Committee, saw-whet owls have been documented as breeding in Rhode Island just six times since 1952. Two of those records occurred in the last two years and were documented as part of the Rhode Island Breeding Bird Atlas, which is managed by ornithologist Charles Clarkson.
            “It seems like the species is maintaining a small but persistent breeding population in the state,” Clarkson said.
            But many more saw-whet owls migrate through Rhode Island. Those that are captured by Comings and Paton are revealing interesting details about their migration patterns.
            “We have a much better idea of their migratory pathways,” said Paton. “We’ve also learned that they’re much more common than people used to think. And we see an annual variation in their numbers.”
Paton said that the number of saw-whet owls migrating through the Northeast rises and falls every other year based largely on the number of acorns and other seeds produced by trees in the area. When trees produce large numbers of acorns, they provide abundant food for small mammals like mice and voles, whose populations then skyrocket. When the small mammal numbers increase, saw-whet owl numbers grow, because the owls eat the mammals and can produce more chicks.
Most of the owls caught in Rhode Island fly to the mid-Atlantic states.
“We know that because we’re starting to build a database of where the birds have been caught and where they’ve ended up,” explained Comings. “I’ve had birds I’ve caught recaptured by others in New Jersey, Massachusetts and Maryland, and I caught birds that had previously been banded in Cape May, New Jersey, and Massachusetts.”
Paton has similar records. “One year I caught a bird at my house in Richmond, the next year it was caught in northern Maine, and a week after that it was caught at Audubon’s Eppley refuge in West Kingston.”
One of the more unusual findings from Project OwlNet is that birds migrating for the first time often take a different route than older birds who have previous migration experience. First time migrants tend to be caught along the coast, while adult birds are more likely to follow an inland migratory route.
“The older birds know better when to fly; they’re a little more savvy,” Comings said. “If you’re an adult bird and this isn’t your first rodeo, you know to wait for a northeast wind, which takes you on an inland route. If you’re a young bird, you know you’re supposed to go on a north wind, but if it’s from the northwest it pushes you toward the coast. Almost all the saw-whet owls I catch on Block Island are young ones.”
So far, this year has been a quiet one for saw-whet owl migration. Through the first week of November, Paton had captured only one owl, and Comings hadn’t fared much better.
“It’s been really slow this year because the winds haven’t been right,” Comings said. “But there’s still time. I’m just waiting for that one big night.”

This story first appeared on EcoRI.org on November 16, 2017.

Wednesday, October 25, 2017

Scientists create 'observatory' to monitor climate impacts on Narragansett Bay

            A group of scientists from almost every college and university in Rhode Island is constructing what they call a bay observatory to continuously monitor and model the changes occurring in Narragansett Bay as a result of the warming climate. The system of data-collection devices will include sensors to detect environmental conditions, a “cyto-bot” to photograph micro-organisms, and a way to transmit the data to a publicly-accessible website.
            “We need to improve our ability to measure changes in climate variability and nutrient pollution, in terms of both time and space,” said Geoff Bothun, a professor of chemical
engineering at the University of Rhode Island and a leader of the project. “More accurate measurements at lower detection limits with greater frequency and finer spatial resolution will help dramatically to predict and plan for what is to come.”
            The new instruments will be deployed in Greenwich Bay, in the waters just off the west coast of Conanicut Island, in the bay’s East Passage and elsewhere.  Each will be able to collect data about water temperature, salinity, pH, nutrient levels, dissolved oxygen, currents, and wind speed, while also monitoring biological and biogeochemical activity.
            “We’re trying to understand how various stressors – both human caused and natural – can impact the ecology of Narragansett Bay,” said Lewis Rothstein, a URI oceanography professor. “It’s designed to look at the whole bay ecosystem, highlighting those individual components deemed most important for hypoxia [oxygen deficiency] events, for example.”
One of the unique aspects of the observatory is that it can be programmed to respond to events and trigger a response,” added Bothun. “If we begin to see spikes or trends that are an indicator of an algae bloom, for example, we can trigger our cyto-bot to begin taking more frequent images so we can see the microbiology in the bay at the same time that the measurements are being taken.”
            Although there are already a number of oceanographic measuring devices scattered around Narragansett Bay to collect data for the Rhode Island Department of Environmental Management and scientists at URI’s Graduate School of Oceanography, this new effort requires more precise data that can be fed into computer models to forecast changes that are likely to happen in the near future. So the research team must design and build a new generation of sensors that can more accurately detect minute quantities of various compounds of interest.
            “This is a tough problem, but my vision is to use living biosensors – microorganisms that respond to nutrients and can report to us what’s going on and what molecules are present in the bay,” explained Jeff Morgan, professor of medicine and engineering at Brown University, who leads the sensor development team with URI Chemistry Professor Jason Dwyer. “There are a number of living microorganisms that are terrific at detecting, sensing and reporting the presence of certain nutrients in the environment.”
            Other researchers will approach the sensor development effort from other directions, including nanotechnology solutions, paper-based sensors, and sensors that can be used by citizen scientists.
            All of the data collected by the bay observatory, along with historic data about Narragansett Bay, will eventually be fed into computer models being developed by Rothstein, Baylor Fox-Kemper, associate professor of earth, environmental and planetary sciences at Brown, and others. Their aim is to forecast changes that might occur at a particular place or time so that local decision makers have time to act on those changes.
            “The observatory is in place to do the heavy lifting for us,” Rothstein said, “but we’ll only have instruments at certain spatial points. The modeling is essentially trying to represent what we observed at those locations and interpolate observations at locations where we don’t have instruments. That will allow us to observe the entire bay.
“All of the forecasts will be analyzed and visualized in ways that will provide public and private decision makers with the tools they need to optimize their decisions for the benefit of all Rhode Islanders,” he added.
            The models will also incorporate data from social scientists to factor in the impact of human behavior and how people may behave differently to mitigate particular changes taking place in the bay.
            The researchers will also create an on-line depository they are calling the Rhode Island Center for Data Discovery that will include all of the real-time observational data and modeling data, along with images and historical data.
            “The public will be able to click on a point in Narragansett Bay and take a look in real-time at temperatures or circulation or other ecological variables about that point at a particular time,” Rothstein said. “That will be a legacy program for us.”
            The Bay Observatory is one element funded by a $19 million grant from the National Science Foundation to establish the Rhode Island Consortium for Coastal Ecology,
Assessment, Innovation and Modeling. The grant will be augmented with $3.8 million from the Rhode Island Science and Technology Advisory Council. The collaboration consists of researchers from URI, Brown, Rhode Island School of Design, Rhode Island College, Bryant University, Providence College, Roger Williams University and Salve Regina University.

This article first appeared in EcoRI.org on October 25, 2017.

Saturday, October 21, 2017

That glimmer and glow in the ocean

            That strange glow you sometimes see for a brief moment when you’re standing on the beach at night and staring toward the crashing waves might not be your eyes playing tricks on you after all. It also might not be the moon’s reflection or the flicker of an underwater flashlight or any other explanation you may have come up with. That strange glimmer in the water may be real, and it may have a natural explanation.
            I’ve been curious about the phenomena of bioluminescence – the chemical production of light by living organisms – for many years. In the terrestrial environment, fireflies do it, as do some beetles and a few mushrooms. But in the ocean, numerous creatures can produce light
Bioluminescent plankton in the Maldives (Doug Perrine)
under various circumstances – to lure prey, to attract a mate, or to frighten predators away, among other reasons. In Monterey Bay, California, scientists recently calculated that three-quarters of all marine species are bioluminescent.
In the waters of the Ocean State, bioluminescence is most often seen in the late summer and fall when some types of microscopic plants called dinoflagellates multiply in large numbers. If there are enough of them, these dinoflagellates will glow when disturbed, like when waves crash around them. If you are out boating on the water at night under the right conditions, they also might glow when you jump in the water or start your engine.
Some grape-sized jellyfish called ctenophores and a few kinds of tiny crustaceans also use bioluminescence in local waters.
According to Jim Sullivan, a Providence native and former marine scientist at the University of Rhode Island who is now a professor at Florida Atlantic University, bioluminescence typically occurs when a particular protein and enzyme combine in the body to release photons of light. Creatures typically keep the protein and enzyme separated inside specialized structures in their cells until they are triggered to come together.
“There’s a biochemical control for turning it on and off,” he told me. “In the case of the dinoflagellates, it typically happens when another organism goes to eat them, but they flash as soon as they are touched, and that flash startles the predator, which lets goes of it and runs away.”
The flash of light might also attract a larger predator to come and eat the smaller predator.
A great many questions still remain about bioluminescence, yet few scientists are studying the subject. The U.S. Navy funded most of the research into bioluminescence in the 1980s and 1990s when it believed that modern satellites might be able to detect the movement of submarines by the trail of bioluminescence in their wakes.  Sullivan conducted studies of bioluminescence off Iceland back then when Russian submarines were known to frequent the waters in the area.
Today, the research funding has dried up, but it’s still a fascinating phenomenon to observe.
My only experience with bioluminescence in the ocean was during a midnight walk out to Napatree Point in Westerly several years ago when I was volunteering to monitor breeding horseshoe crabs. During a break in the action, I stared toward the crashing waves and saw what appeared to be a brief blue-green flash of light. It reminded me of a distant flash of lightning or the green flash some say is visible at the moment the sun sets.
Or maybe it was just my eyes playing tricks on me.

This article first appeared in the Newport Daily News on October 21, 2017.

Wednesday, October 11, 2017

The hunt for red October

            Rhode Islanders pay close attention to the changing foliage colors each fall and are justifiably proud of the picture-perfect show the region’s trees put on every year. But Keith Killingbeck, 67, probably pays closer attention than most. A recently retired professor of plant ecology and biology at the University of Rhode Island and the former assistant dean of the URI Graduate School, he has been studying the nutrient dynamics and energy flow in trees – the process that causes the leaves to change color – since his grad school days at the University of North Dakota. A native of Michigan who moved to Rhode Island in 1979, Killingbeck said that despite his 36 years teaching botany, he didn’t start out with a particularly strong interest in plants and foliage. “My passion is for nature and the outdoors and everything and anything that’s part of it.”

Q: Why does New England have the reputation for having the best fall foliage colors?
A: It has to do with the tree species we have and the climate we have. Often in New England we’ll have sunny days and cold nights in the fall, and the tree species that we have respond to
Fall foliage in New England (Glen Russell)
that with a number of chemical changes in their leaves that yield the brilliant colors we see.

Q: What do trees do to produce those colors?
A: One of the most important things they do is break down compounds like chlorophyll to save some of the nutrients, especially nitrogen and phosphorous. Those nutrients are being shunted out of the leaves and moved back into the trees to be saved to be used in the next growing season. It’s essentially a conservation strategy.

Q: Why do different trees exhibit different colors?
A: There’s no easy answer to that. But if we look at birches, they turn yellow. Yellow pigments are unmasked as the green chlorophyll molecules are broken down, and as some of the nutrients are moved out, you have these xanthophylls – accessory pigments in tree leaves -- that show up as bright yellow. Tupelos turn a red-maroonish color, and those are from anthocyanins, a whole different kind of chemical, which are being built up in the fall rather than unmasked. They protect some of the photosynthetic systems in the leaves. It’s complicated.

Q: Do you have a favorite tree for its fall foliage?
A: I’ll give you three. My favorite tree in New England is sugar maple for its peachy color. This is an oddball, but I also like poison sumac, which has this beautiful orange color to its leaves. The third one is Virginia creeper, a vine that has beautiful maroon leaflets in fall.

Q: What factors influence the timing of when leaves change color?
A: The amount of daylight, or photoperiod, is one of the main kickers in all this. Photoperiod is constant from year to year to year, so it’s a good trigger for plants and animals for the timing of anything they do. Within that time period, though, everything from daytime versus nighttime temperatures, precipitation, drought, all those things really impinge on and impact the leaf changing color. The chemistry that’s going on during that time is impacted by all those factors, but photoperiod is a constant predictor of where we are on a year’s cycle.

Q: It doesn’t appear that the leaves all change at the same time. Why not?
A: They certainly don’t. In mid-September, many birches have yellow leaves already, Virginia creeper has maroon leaves already, but most of the leaves on other species are still green – oaks have not turned, most of maples have not turned. Individual species change at different times. In southern Rhode Island, for example, the peak of red maple color is probably around the second or third week in October. Oaks are going to be later, others earlier. It’s species by species and also individual site by individual site. Red maples in very wet areas are going to have their leaves turn earlier than red maples on a much drier site.

Q: How will the gypsy moth defoliation affect the fall foliage?
A: In those areas hardest hit, virtually all the leaves were eaten. Some of those trees that didn’t die reflushed some leaves, but as I’ve looked at some of those trees, the new leaves that were produced after the defoliation were much smaller and there are many fewer of them. So even if those individual leaves turn bright colors, there’s not enough leaf mass to show much color. And, of course, those trees that died, you’ll get no color out of them.

Q: What other factors affect foliage from one year to the next?
A: Ideally, to bring out the most vibrant colors, what works the best is bright sunny days when there is a lot of photosynthesis – they’re producing sugars during photosynthesis – and cool nights for depressing the rates of metabolism so those sugars being produced in daytime are not used up as rapidly as they would be on warm nights. So it’s those sunny days for good photosynthesis and chilly nights. That’s the perfect recipe for vibrant leaves.

Q: Based on those factors, do you have a prediction for what this year’s foliage is going to be like?
A: It’s certainly going to be at the usual time, not knowing what the upcoming weather is going to be, because the variation in timing from year to year is pretty small. I’ve been following leaf color change in individual trees for many years, and the timing changes only by a few days from year to year.  The amount of rain we get, when we get rain, the temperatures at night all make a difference, but it’s very subtle. This year the thing that’s going to impact our color most is whether trees were defoliated in spring and early summer. But other than pockets of trees that were defoliated, I think the colors are going to be great again this year.

Q: Why do some individual trees change color especially early, like in August?
A: I’ve observed that also, and in fact I have a single red maple tree that I call my early red maple that I see when I drive to campus every day. It turns earlier than any of the other red maples around it. I think it’s genetics. The genetic makeup of the individual. The environmental conditions are the same versus trees meters away – whether it be soil conditions, rainfall, sunlight, anything else – so the difference has to be attributed to genetics.

Q: Is climate change likely to have an effect on foliage colors or timing in the coming years?
A: The simple answer is yes, as far as we can tell. There are certainly phenological studies around the world that show plants budding earlier in the spring than normal, extending the growing season on the front end, and it appears that leaves are being held onto later in the fall, at least for some species, extending the growing season on the tail end. So it certainly seems that the warming of the planet is having an effect and will continue to have an effect.

This article first appeared in the Newport Mercury on October 11, 2017.

Sunday, October 8, 2017

Wildlife rehabilitators in Rhode Island

            At the end of a quiet dead-end street in Westerly, a three-story brick house is surrounded by a maze of shed-like structures that seem only slightly out of place. The largest is 40-feet long and 12-feet tall and sheathed almost entirely in wire screening. Inside, laying on a tree stump, is the carcass of a half-eaten squirrel. And perched on a beam above the carcass are two female red-tailed hawks – Griffin, a 7-year-old with a deformed beak, and Matrix, 15, who has a traumatic head injury from being struck by a golf ball at a country club in Massachusetts.
The two birds periodically fly the length of the cage to exercise their wings, then swoop
Baby cottontails (James Jones)
down to peck at the squirrel carcass. Every year, one of them lays an infertile egg, and the birds take turns incubating it until they realize it’s not going to hatch.
            Adjacent to the flight cage are a dozen 8-by-10-foot cages. In one sits a turkey vulture named Lurch with neurological damage caused by ingesting something poisonous at the Charlestown landfill. Next door is Krypto, a peregrine falcon born on the Superman building in Providence but who flew into a window of the downtown Blue Cross Blue Shield building, breaking its wrist and causing a head injury. Nearby, two barred owls perch in a darkened section of their cage, one-eyed Wink and his partner Boytoy, who was rescued after being struck by a car.
            The newest cage, built last year with the help of a local eagle scout, houses a red-tailed hawk that struck a window so hard that the homeowner thought it was a gunshot.
“It was paralyzed for 11 days, but on the 12th day we arrived to see it standing up, and it’s slowly getting better,” says Vivian Maxson, who operates the Born to be Wild Nature Center with her husband John. “It now can fly the length of the cage, and we’re hopeful it can be released.”
            Most of the birds at the nature center have permanent injuries and would not survive in the wild, but some are destined to be returned to the outdoors when they heal.
            The Maxson’s started Born to be Wild after taking a wildlife rehabilitation class through the Rhode Island Department of Environmental Management and apprenticing with a certified rehabilitator.
“That person starts you off with easy cases, like baby squirrels or opossums, then you get bumped up to the next level and you’re on your own,” Vivian says. “I really like the feeling of giving back to nature. Man’s impact causes so much harm that it’s a way to try to balance it out.”
            “All it takes is one or two enjoyable cases, and it strengthens us and keeps us going,” adds John.
            The Maxsons have become the state experts at rehabilitating raptors, so almost every hawk or owl in Rhode Island that is found injured or unable to care for itself usually finds its way to their nature center. Every day, they provide the birds with their preferred meal – dead mice and rats for some, squirrels and rabbits for others – and assess the health of each to determine when they are ready for release. When they have time, the Maxsons also host tours of the nature center or bring some of the birds to summer camps and retirement homes for educational programs.
            About 70 hawks and owls spend time at Born to be Wild each year, and about 65 percent survive to be released, a better success rate than the national average. Some must be euthanized because of the seriousness of their injuries.
            According to John, the most difficult hawks to care for are ospreys.
            “They only eat live fish, so every day I have to go fishing,” he says with a smile. “Anyone who visits us in the summer, we hand them a fishing pole and tell them to go catch some fish.”

....Continued in the October 2017 issue of Rhode Island Monthly magazine.