Thursday, July 21, 2016

Extinction predicted within 50 years for local sparrow

            Saltmarsh sparrows are the only species of breeding bird found nowhere else but the East Coast of the United States, where they live exclusively in coastal marshes, including several sites in Rhode Island. But the birds are predicted to go extinct within the next 50 years.
            That’s the unfortunate news reported by University of Connecticut researchers Chris Elphick and Chris Fields earlier this month. Their data shows that the sparrows, which Elphick describes as small songbirds similar to the sparrows that visit many bird feeders in winter, have been declining at a rate of about 9 percent per year since the late 1990s.
Saltmarsh sparrow by R. Crossley/Vireo
            “To put it in context, if your stock portfolio was declining at that rate, you’d be losing money fast. It’s pretty bad,” he said. “About three-quarters of the population has disappeared.”
            According to Rachel Farrell, a member of the Rhode Island Avian Records Committee, birdwatchers in the Ocean State have made similar observations about saltmarsh sparrows, which they used to be able to find in good numbers at numerous salt marshes in the state. Now they report that the birds are few and far between. She said that birders have reported that the sparrows have all but disappeared from salt marshes in Little Compton, and they have declined somewhat in recent years at the marshes at the Charlestown and Quonochontaug breachways and around Ninigret Pond.
            Walter Berry, a research biologist at the U.S. Environmental Protection Agency in Narragansett, has conducted annual surveys of saltmarsh sparrows at Ninigret and Quonochontaug since 2007, and while he hasn’t observed a population decline during that period, he is pessimistic about their future.
            “Saltmarsh sparrows look like they’re holding their own at those sites, but judging by the quality of the habitat there, they won’t be holding their own for very long,” he said.
            The cause of the range-wide decline of saltmarsh sparrows is uncertain, though sea level rise and tidal restrictions at marshes are major factors.
            “The presence of a road across a marsh that restricts the natural tidal flow, even if there’s a culvert that allows the water to go in and out, is one of the most important predictors of decline,” Elphick said. “We found no decline in marshes without tidal restrictions, but the trouble is that nearly all marshes have some sort of tidal restriction.”
            He notes that locations that are experiencing the greatest sea level rise are also the sites where the decline in saltmarsh sparrows is greatest. That’s because the birds nest on the ground in the marsh, and the high spring tide causes many nests to flood.
            “If that only happened once a month, it wouldn’t be a problem because the birds’ nesting cycle takes 23 or 24 days to complete,” Elphick explained. “So if there’s a 24-day window between spring tides, they can reproduce. But if that window gets shorter because of big storms or onshore winds driving the water high up into the marsh, or if the marshes don’t drain the way they would naturally, suddenly the birds don’t have enough time to reproduce.”
            To complicate things, Elphick said that as sea level is causing the peak of the high tides to get higher.
            “It doesn’t take too much sea level rise to flip the switch for the birds,” he said. “Literally, a couple inches can make the difference.”
            To draw their conclusions, Elphick, Fields and their colleagues surveyed for salmarsh sparrows at 1,800 locations throughout the birds’ breeding range and compared their results to similar surveys conducted in the 1990s and 2000s. They also monitored nesting success and estimated the survival rates of adult birds.
            Sadly, the researchers say there is little that can be done to protect the birds in the long term, since any steps taken now to reduce sea level rise won’t have a practical effect until it’s too late. They are exploring several short-term or temporary fixes, however, like identifying the marshes that are least susceptible to the effects of sea level rise so they can be protected from development or alteration. They are also identifying locations where it is possible for the marshes to move inland as sea level rises so those inland locations can be protected as well.
            But ultimately, Elphick is not optimistic about the future for saltmarsh sparrows.
            “This is a really difficult problem, one we’ve ignored, and the longer we ignore things the harder they are to fix,” he said. “It’s not just about the sparrows, though. That’s just one species in these marshes. If we start acting now, all the things we do to benefit this sparrow will also benefit all the other species in the marsh, even if it doesn’t work for saltmarsh sparrows.
“This sparrow tells us there’s something bad happening in the system that we have to act on now if we’re not going to run into bigger problems down the road,” he added.

This article first appeared in EcoRI.org on July 20, 2016.

Tuesday, July 19, 2016

Researcher worries shark fishermen may capture his research subjects

           It’s the peak of shark fishing season, when hundreds of fishermen enter tournaments throughout southern New England and Long Island to catch the biggest shark in nearby waters. And it has BradleyWetherbee worried.
            The University of Rhode Island shark researcher knows that one mako shark he tagged off the coast of Maryland last year – which a sponsor named Charlotte – arrived in Rhode Island waters last week after a year-long, 6,500 mile journey. And given his track record of having his tagged sharks captured and killed by commercial and recreational fishermen, Wetherbee has his fingers crossed that Charlotte survives the month.
            “Makos are caught in all kinds of fisheries all around the world,” he said. “They’re the shark everyone wants to catch because they’re good to eat – like a shark version of swordfish – and they fight and jump and put up a big battle.
            “But it takes a great deal of effort and money to catch and track sharks, and we don’t want to see our research subjects captured and killed and lose their contribution to science,” he added.
            Wetherbee doesn’t object to shark fishing. In fact, his research is aimed at collecting information about the animals so they can be better managed and available for sustainable harvest for many years to come. He just hopes that any fisherman who catches Charlotte or any other shark with a satellite tracking tag on its fin will release the shark back in the water unharmed.
            Little is known about the health of mako shark populations, the migratory routes they travel, or their preferred feeding grounds. Wetherbee hopes his research will help to answer some of these questions. Makos are especially difficult to manage because they travel through the waters of dozens of countries, thereby requiring significant international cooperation to protect them from overfishing.
            Shark fishing isn’t the only threat to mako shark populations, however. The demand in China for shark fin soup is causing 70 million sharks to be killed each year for their fins. And while little shark finning takes place in New England waters, mako sharks have a worldwide distribution, so they are among the most commonly captured shark in the finning trade.
            Wetherbee and his colleagues at the Guy Harvey Research Institute at Nova SoutheasternUniversity have tagged more mako sharks in the Atlantic Ocean than any other scientists. The satellite tags they attach to the sharks’ fins enable the researchers to track the animals’ movements from day to day, which is how Wetherbee knew exactly when Charlotte arrived back in Rhode Island waters. It’s also how he knows that nearly a third of the 50 mako sharks he has tagged in recent years have been caught and killed by fishermen.
            “It’s easy to see the track lead right to a port somewhere and the tag just ends up sitting on a dock,” he said.
            The data Wetherbee is collecting from his tagged sharks is providing estimates of mako shark mortality that are far higher than scientists once believed.
            “So it’s possible that they are being overfished much more than previously thought,” Wetherbee said.
            His tagged sharks have moved through the waters of 27 countries. One shark traveled 14,000 miles in one year, and many have traveled more than 10,000 miles. Charlotte’s route took her from Maryland to Virginia, then north to Rhode Island and Long Island, where she spent several months last fall.  She then returned south to North Carolina before going on a two month loop far out into the Atlantic in April and May. She returned to south coastal waters in June, and then traveled to Rhode Island, where she arrived last week.
             “It’s information that no one had any idea about – their movements, how much time they spend in the north in winter, the countries they visit,” Wetherbee said. “It’s generating a lot of great information that is useful for managing shark populations.”
            The URI scientist said that Charlotte is obviously unaware of the risks she is taking by arriving in Rhode Island waters at this time.
            “She’s running the gauntlet,” he said. “There are three shark fishing tournaments just in tiny Rhode Island, and many more in Massachusetts and Long Island. There are hundreds of boats out there that would like to kill her and eat her. And if she makes it up to Canada, that’s where the longline fishery takes place. That’s another place she could easily get caught.
            “If I were Charlotte’s parent, I’d be crossing my fingers that she makes it out of here alive,” Wetherbee said.
            Monitor the movements of Charlotte and the other sharks Wetherbee has tagged here

Monday, July 18, 2016

Rhode Island aids cause, bans shark fin trading

            The first shark I ever saw was about 25 feet long – nearly as long as the research boat I was on – and it repeatedly cruised back and forth under and around us as we drifted in Cape Cod Bay.  Then it glided to the surface and just floated next to us, unmoving, its giant fin jutting above the water line. It was a basking shark, the second largest shark on Earth, and I quickly put my wetsuit on to join a film crew in the water with it. But it disappeared before I was ready.
            I haven’t seen many sharks in the wild since that day, but I’m often reminded of that shark’s massive fin, perhaps two feet tall, and how the animal seemed to have no fear of us. Sadly, that giant fin and the shark’s lack of fear – along with the great demand in China for shark fin soup – has put basking sharks and many other shark species at great risk.

     Brad Wetherbee, a shark researcher atthe University of Rhode Island, said about 70 million sharks die each year from having their fins sliced off to meet the demand for shark fin soup. The reportedly tasteless delicacy is served primarily at weddings and other celebrations in China and at Chinese restaurants in the U.S. and elsewhere.

            ”It’s the biggest issue in the world that sharks face,” Wetherbee said. “If you could do away with one thing to benefit sharks, it would be finning.”
            Slicing off a shark’s fins causes the animal to die a slow and cruel death. Wetherbee likened it to trying to fly a plane without wings. The sharks just sink to the bottom, unable to swim, and die.
So it was heartening to learn last month that Governor Gina Raimondo signed into law a bill that makes it a crime to own or sell shark fins in Rhode Island, unless it is for use in scientific research. It makes the Ocean State the 11th state in the nation to ban the trade in shark fins. And while there isn’t believed to be much of a market for shark fins in Rhode Island, the law is useful in raising awareness of the practice of shark finning and the ecological damage it does.
            Basking sharks have no teeth and feed exclusively on tiny plankton, which is why some biologists call them whales in shark’s clothing – they eat what most of the large whales eat. It’s also why I felt comfortable getting in the water with one. They are no threat to humans or almost any other creature. Yet they are targeted by some fishermen because just one of their massive fins can sell for tens of thousands of dollars in China.
            The depletion of global shark populations due to finning is causing a ripple effect – what scientists call a trophic cascade – that is affecting numerous other species, from shellfish and corals to sea turtles and commercially important fish. So reducing the slaughter of sharks for their fins will not only benefit the sharks, but many other marine creatures as well.
            Wetherbee said that Rhode Island’s ban on the sale of shark fins probably won’t reduce shark mortality a great deal. “We’re just a tiny state, but we want to be on the right side of this issue and make a statement about it. So in that respect it’s a good move for Rhode Island.”

This article was first published in The Independent on July 21, 2016.

Wednesday, July 6, 2016

Where the wild things are

What's the story behind the increased spottings of bobcats, bears and coyotes in Rhode Island?

The bright orange tackle box in the back of Charles Brown’s state-owned pickup truck is filled with all sorts of lures, none of which have anything to do with fishing. Instead, like the shelves in a chemistry lab, it contains small, colorful bottles of murky liquids emitting unappetizing aromas. With names like Cat-man-doo, Gusto and Cat Fancy, their contents are used by trappers and hunters to attract predators. One, called Booty Call, contains a putrid mix of secretions from a bobcat’s anal gland that Brown carefully applied to a series of box traps he and University of Rhode Island researcher Amy Mayer set up in South Kingstown last winter.

Mayer and Brown, a wildlife biologist for the Rhode Island Department of Environmental Management (DEM), used the lures almost daily for five months last fall and winter as part of a project to capture bobcats in South County. Their objective was to assess what appears to be a growing population of the state’s only wild feline. The animals have been sighted with increased frequency in almost every community in mainland Rhode Island, but little is known about how widely they travel, what they eat and other aspects of their behavior and ecology.

Growing up to thirty-five pounds, bobcats are the most widely distributed wild cat in North America, where they can be encountered in deserts, prairies, mountains and coastal regions. They have always been present in Rhode Island, though they have gone through periods when they were quite scarce. Today they are most often reported in South Kingstown, Westerly and Foster, though they are known to travel through the most densely populated areas of the state as well.

Bobcats are among a group of large predators, including black bears, fishers and coyotes, that are making some residents feel that their suburban communities have become more like the wilds of Yellowstone National Park than the safe enclave to which they had been accustomed. And although the animals’ arrival in the region has been spread out over several decades, many people perceive that the predators have recently become increasingly bold as they wander through neighborhoods and brazenly stand their ground.....

Read the full feature story in the June issue of Rhode Island Monthly.

Friday, July 1, 2016

Caterpillars, defoliation may benefit some wildlife

The massive defoliation of trees in southern New England by winter moth and gypsy moth caterpillars this spring and summer has totally changed the look of the regional landscape. And while scientists say it is unlikely that many trees will die as a result of one year of defoliation, it raises the question of how it will affect other species of wildlife.

University of Rhode Island ornithologist Peter Paton says that several varieties of songbirds are likely benefiting from the huge number of caterpillars swarming the area. Black-billed and yellow-billed cuckoos, two species that are known to eat large numbers of caterpillars, including the prickly gypsy moth caterpillars that many other birds avoid, are likely to thrive this year. He said that birdwatchers in the region have noticed an unusually large number of very active cuckoos since the birds arrived from their wintering grounds in South America in May. As a result, the birds will probably have a very successful nesting season.

“Last week I was watching some robins 40 feet up in a tree foraging, which is a pretty unusual place to find them eating,” he said. “So I’m guessing they were probably feasting on caterpillars, too.”

Paton also observed blue jays and hairy woodpeckers tearing apart some of the abundant caterpillar cocoons, another unusual behavior brought about by the caterpillar infestation.

“And if the defoliation ends up killing trees,” he added, “that could eventually have a positive impact on woodpeckers,” which consume insects that live in dead trees and which drill nesting cavities in dead trees.

As for other possible effects on wildlife, he speculated that the absence of leaves on many trees will enable sunshine to filter down to the forest floor and other areas that are typically shady, which may provide additional sunny areas for turtles and snakes to nest and sun themselves.

On the other hand, fewer shady areas may make it more difficult for wood frogs and salamanders living in the forest to remain cool and moist, according to David Gregg, executive director of the Rhode Island Natural History Survey.

“Ferns and other forest floor plants are also more likely to have a negative experience of this phenomenon than a positive one,” he added.

Natural History Survey botanist Hope Leeson said there will be both winners and losers on the forest floor, depending on the needs of the species living there. “If there is an understory of trees and shrubs, they’ll be happy to have the sun.”

Leeson points to greenbrier as one plant that will thrive with the additional sunlight penetrating to the forest floor, and it will provide benefits to other species that may be at risk.

“At the moment, any small mammal living in the forest doesn’t have any cover,” she said. “Deer have eaten all the tree seedlings and shrub seedlings, so there isn’t anything for the mice and chipmunks to hide under. Once the canopy was removed by the caterpillars, it made it easy for the hawks and owls to see the small mammals pretty well.”

The increased growth of greenbrier, she said, will provide the small mammals with new places to hide.

Leeson and Gregg also noted that some unwanted invasive species may also thrive this year, thanks to the defoliation. Amur cork trees, for instance, an Asian species, have invaded forests throughout the Mid-Atlantic States and are now found in small numbers in coastal forests of Rhode Island as well. They grow very slowly in the shade, with some 25 year-old trees no more than eight feet tall with trunks only an inch or two in diameter.

“They just wait it out in a shady situation,” Leeson said. “They just eek out an existence and wait for the moment when there’s light, and that’s when they put on a lot of growth.” And this year could be the year they will shoot skyward.

According to Rick Enser, retired biologist for the Rhode Island Department of Environmental Management, if the region experiences another gypsy moth infestation next year, tree mortality will likely increase, which could create gaps in the forest for new species to move into.

“Unfortunately, invasives are highly adept at dispersal, although small infestations within forest openings should theoretically be reduced or eliminated as the canopy returns,” he said.

He points to winged euonymus, also known as burning bush, as one invasive species that can spread quickly to new areas and survive when the forest canopy returns. It is a shrub that has become a primary concern at URI’s W. Alton Jones Campus.

Because it has been more than 30 years since Rhode Island has experienced such a severe defoliation, many of the environmental effects are uncertain and unstudied, leaving some scientists with more questions than answers.

“I was wondering about the nutrient balance,” said Gregg. “Normally oak leaves breakdown in a certain way at a certain time, but this year they've been consumed by caterpillars and turned into manure and sprinkled all over the forest floor. So is that good for the plants? What's the nutrient analysis of gypsy moth poop?”


This article first appeared in EcoRI.org on June 29, 2016.