Sunday, October 25, 2020

Fungal disease plagues porcupines

        Porcupines are quite common across the northern tier of the United States, but scientists at the New Hampshire Veterinary Diagnostic Laboratory have discovered a crippling fungal disease that is often fatal, and it could have implications for the long-term health of porcupine populations in the region.
        As part of a study of porcupine mortality in Maine, New Hampshire, and Massachusetts, pathologists at the lab examined 44 dead porcupines during a 7-year period and found 12 had died from a disease caused by a fungus known to cause ringworm in wild and domestic animals.
        “The fungus usually causes localized, often minor skin infections in animals and people,” said
Porcupine with fungal disease (NH Veterinary Diagnostic Lab) 

veterinary pathologist David Needle. “In porcupines, however, the skin lesion becomes severe and spreads to the whole body, resulting in debilitation and death if not treated. The pattern of disease caused by this fungus has never been reported in porcupines.”
        The porcupine’s response to the fungus is to try to slough it off by growing a large quantity of keratin, which Needle describes as “a self-adhesive sheet of dried-out cells.” But because the fungus thrives in keratin, and because no inflammation blocks the fungus, the fungus eventually grows over the animal’s entire body, including its eyes and ears in some cases.
        Because the disease has only been diagnosed in the three states – plus a new case in Connecticut – Needle believes that a regional subpopulation of porcupines may be susceptible to the pathogen. Additional cases have been identified by wildlife-rehabilitation clinics in the region, and a newly developed treatment protocol is having modest success at healing the animals.
        The fungus is zoonotic, which means it can be transmitted from animals to humans, although there are no reported cases of humans becoming infected by porcupines. But it is emerging at the same time that several other fungal diseases are affecting other wildlife populations around the world, from bats and frogs to snakes and salamanders.
        How the disease found its way into porcupines is unknown, but Needle speculates that it probably emerged in the last decade and may be spreading. Because porcupines are not commonly rehabilitated and not studied extensively, it is unknown how common the disease is at this time.
        “Porcupines are quite populous in some areas and are sometimes viewed as a pest, so concern for their population numbers isn’t a high priority,” Needle said. “There isn’t a groundswell of financial backing to investigate the disease further. But in areas where fishers had been extirpated and have been recently reintroduced, there has been a plummet in porcupine populations. Added pressure from this fungus is not helping them. They are still common enough in New England that we are not aware of a significant population decline, but studies to assess this may be lacking.”
        To get a better idea of how widespread the disease is, Needle is now assimilating data from 400 dead porcupines studied at diagnostic labs across the country during the last 20 years. “We just started, but this new disease might be the most common diagnosis,” he said.

This article first appeared in the autumn 2020 issue of Northern Woodlands.

Friday, October 23, 2020

Search for rare salamander takes place in the dark

        After dark at a well-hidden vernal pool in Richmond, Peter Paton shined his flashlight back and forth at the moss-covered ground around the nearly-dry pond basin. He was searching for marbled salamanders, the only autumn-breeding salamander in New England, and one that is seldom seen except on rainy fall evenings. It didn’t take him long to spot one.
        “I got one,” he called out. “Over here.”
        Marbled salamanders are the second largest salamander in the region – after only the spotted salamander -- and their attractive black-and-white patterning makes them unmistakable. The one Paton found, a male, was on his way out of the pond basin, indicating that the animal had completed his
mating duties and was headed to the forest to spend the winter underground.
        Female salamanders were likely hidden in the sphagnum moss around the pond, where they remain for a month or more to guard their eggs until rain fills the pond and the eggs are protected from predators and the elements. The eggs hatch within days after being covered in water, and the larvae overwinter in the pond.
        Paton, a professor of natural resources science at the University of Rhode Island, was confident of finding
Marbled salamander (Todd McLeish)
marbled salamanders at the Richmond site, since it was a place he studied and monitored in 2000 and 2001, when he and colleagues conducted an amphibian survey of 137 vernal pools around the state. Marbled salamanders were found in just four of the pools, however, making it one of the rarest pond-breeding amphibians in the region.
        Previous efforts in the 1980s and 1990s by Chris Raithel, a wildlife biologist at the Rhode Island Department of Environmental Management, documented as many as 50 marbled salamander breeding sites in the state, mostly in Kent and Washington counties. There are no records from Bristol county or from areas adjacent to Narragansett Bay and few from the Blackstone Valley.
        “The present localized distribution of marbled salamanders in Rhode Island may be related to habitat fragmentation and patch isolation,” Raithel wrote in his 2019 book, Amphibians of Rhode Island. “If this effect is real, the species is secure only in the larger contiguous habitats of southern and western Rhode Island, and additional range retraction should be evident to future generations.”
        Marbled salamanders require a very specific habitat for breeding – ponds that are surrounded by sphagnum moss and dry up in the summer, keeping fish and large dragonfly larvae from inhabiting the pond and preying on the salamander larvae.
        “They tend to like relatively small ponds, and there aren’t many sites available that fill their habitat requirements,” Paton said.
        In addition to habitat fragmentation, road mortality is also a significant concern for the species, because they are often crushed by vehicles as the adults cross roads to reach their breeding ponds or as juveniles disperse to find territories.
        On the other hand, Paton said it’s possible that the changing environmental conditions associated with the warming climate may make southern New England more favorable to marbled salamanders in the future. Their current range extends as far south as northern Florida and eastern Texas, and populations in warmer climates tend to be considerably larger than those in Rhode Island.
        “They aren’t very tolerant of the cold, so we’re at the northern limits of their range,” Paton said. “The larvae don’t grow much in the winter because it’s too cold, but once wood frogs arrive to breed in early spring, the salamander larvae feed on the frog tadpoles as their main fuel source to undergo metamorphosis.”
        After metamorphosis, the salamanders leave their ponds and spend the rest of their lives in the forest, except for brief breeding periods each fall.
        Despite how few marbled salamander breeding sites were found during the last amphibian survey, a recent graduate student at the University of Massachusetts at Boston thinks a new survey method may detect the salamanders more effectively than traditional sampling methods.
        Jack He, who graduated in May, used eDNA – environmental DNA collected from water or soil – to detect the presence of marbled salamanders even when the animals could not be seen.
        “Everything sheds DNA in one form or another, like from skin cells or blood, and they release it into the environment,” He said. “Ideally we can collect water or soil samples containing those cells and extract that DNA and sequence it to determine what species are present.”
        He detected marbled salamander DNA in a number of water and soil samples from vernal pools in western Massachusetts. He calls it a less labor-intensive method of determining if the salamanders are present at a site than using dipnets to capture larvae in the spring, which is how Paton conducted his survey.
        “I’ve done dipnet studies and compared them to eDNA, and I found that eDNA was a bit more effective,” he said.
        Paton, however, isn’t convinced.
        “My impression is that larvae are relatively easy to find, but I could be biased,” he said. “Maybe they’re in there and I missed them a lot. But however you do it, I suspect that marbled salamanders are still fairly rare in Rhode Island.”

This article first appeared on on October 22, 2020.

Tuesday, October 20, 2020

Some bats are migratory contrarians

        October is one of the busiest months of the year for migration.
        Millions of songbirds that spent the summer breeding in the Northeast – warblers and flycatchers and orioles, for instance – are winging their way southward to Central America, South America or the Caribbean to enjoy the warm climate and to feed on the abundance of insects that are mostly absent during our northern winters. They’re joined by an equal number of their offspring, all of whom are making the dangerous journey for the first time.
        At the same time, geese and ducks and finches and many sparrows are heading southward from the north, destined to spend the winter eating from our bird feeders or carousing in our ponds or along our
Little Brown Bat (Kentucky Fish and Wildlife)
 coastlines. For them, the New England winter is their version of the Tropics. They’re accustomed to chilly winters and adapted to eating seeds or mussels or whatever else we have available in winter.
        Our few migratory butterflies and dragonflies have departed by now, too, in their search for warmer temperatures to the south. Reptiles and amphibians are also on the move, just not nearly as far – mostly to nearby underground lairs or to the muddy bottoms of ponds and streams.
        But strangely enough, one group of animals is going in the opposite direction. Most of our bats are migratory contrarians. October is the time when they are moving northward instead of south, toward caves and mines in Vermont, New Hampshire and the Adirondacks.
        They’re seeking out a very precise environmental condition – high humidity and a temperature that will remain stable a bit above freezing for the next five months. That’s where they’ll hang together from the ceiling, sometimes in large numbers, in a state of inactivity and slow their metabolism so they don’t have to eat or drink for the entire winter. Rhode Island doesn’t have any suitable caves or mines in which bats can hibernate, so most of our bats head to those closest to us, all of which are to the north and northwest.
        These bat caves – officially called hibernacula – are the perfect location for their long winter naps. But because the bulk of the region’s bat populations are all gathered together in a very few sites, it made it easy for an unexpected disease to rapidly spread among them. Bunched together wing to wing, a deadly disease called white nose syndrome was quickly passed from one bat to another – sort of like Covid-19 among party-goers – and over a few short years close to 90 percent of our bats died.
        That’s why we’re seeing far fewer bats now than we did 20 years ago. The one exception is a species called the big brown bat – as opposed to the little brown bat, which used to be the most abundant species in the Northeast. A few big browns have found enough old buildings, underground bunkers and earthen crevices in Rhode Island with adequate enough conditions to keep them home for the winter. Which may be one factor – along with good genes and naturally occurring probiotics – that has allowed them to survive the disease in greater numbers. Their populations only crashed by about 50 percent.
        I wouldn’t want to suggest that the bats that migrated in the opposite direction of all the other wildlife on our continent are like the clumsy Gang That Couldn’t Shoot Straight, but there’s something to be said for the bat that simply chose to stay home. Maybe, by not migrating at all, the big brown bat is the true migratory contrarian. 

This article first appeared in The Independent on Oct. 11, 2020.

Thursday, October 15, 2020

Survey of knowledge, beliefs about coyotes seeks to inform management

        A University of Rhode Island graduate student is seeking to inform coyote management in Rhode Island by conducting a survey of Ocean State residents to gain insights into their knowledge, beliefs and feelings about the controversial carnivore.
        Kimberly Rivera, of Westchester County, New York, is examining the relationship between what people know and believe about coyotes and their first-hand experience with the animals. She will also factor in their personal environmental beliefs and demographics.
        “Coyotes aren’t going anywhere, so the better we understand where we stand with them, the better we’ll be able to coexist with them,” said Rivera.
        She is seeking at least 500 Rhode Islanders from throughout the state to take the survey before the end of November. It takes about 10 minutes to complete and can be found here.
           According to Rivera, about half of all nuisance wildlife calls received by state wildlife officials are about coyotes, which may have more to do with people’s beliefs about coyotes than it does about the actual threat the animals pose.
        Rivera plans to combine the results of her survey with data from a statewide camera trap study of
Eastern coyote (Todd McLeish)

coyotes to see if people’s opinions about coyotes are more or less positive in areas where the animals are most abundant.
        “We’re going to take what we learn from these surveys and disseminate it to wildlife managers so they can incorporate the data into their management practices,” she said. “If there are areas with greater conflict or where people are especially antagonistic toward coyotes, then maybe we can manage them better for both the coyotes and the people.
        “I’m especially interested in learning about interactions between pets and coyotes,” Rivera added. “There are lots of stories about missing pets suspected of, or witnessed, being taken by coyotes, and I’d like to learn how often it really happens and how often people think it happens.”
        The survey also aims to gauge opinions about current management practices, such as trapping coyotes with foothold traps, which is illegal in the state. Results of the survey may be used to inform future management decisions related to the harvesting of coyotes.
            Rivera’s coyote survey is the result of a survey she had planned to conduct with farmers in Madagascar about conflicts between carnivores and livestock. The pandemic cancelled her travel plans to the island nation off the east coast of Africa, so she sought to focus on a related issue closer to home.
            “I fell in love with spotted hyenas while doing an internship in South Africa while I was an undergrad,” Rivera said. “They’re considered vermin there because they are presumed to depredate livestock. It got me thinking about how perceived interactions can change how people think about a species. Those opinions are important. If people don’t care about animals, we’re not going to be able to conserve or coexist with them.”

Tuesday, October 13, 2020

Scientists investigate effects of marine heat wave off southern New England

        A team of scientists from the University of Rhode Island and partner institutions depart today aboard the research vessel Endeavor for a five-day cruise to investigate the implications of a marine heat wave in the offshore waters of New England.
        The waters on the continental shelf – extending from the coast to about 100 miles offshore – have been 2 to 5 degrees Fahrenheit warmer than usual since July, according to URI oceanographer Tatiana Rynearson, one of the leaders of the expedition. And that warmth could have significant impacts for local fisheries and the marine ecosystem.
           “The water is very warm compared to the average of the last 40 years,” said Rynearson, a professor at the URI Graduate School of Oceanography who studies plankton. “The question we’re
URI ship Endeavor

asking is, how is it affecting the ecosystem and the productivity of the continental shelf waters.”
        The Northeast Pacific Ocean experienced a similar marine heat wave in 2014 and 2015, when what was described as a “blob” of warm water spread offshore from Alaska to California, resulting in major die-offs of fish and seabirds and closures of fisheries.
        “The impacts went all the way up the food chain from that warm blob of water,” Rynearson said. “Similar dramatic impacts haven’t been documented for New England waters, but we’re going to try to understand what’s going on out there.”
        Rynearson hopes the expedition will provide a clearer understanding of how the marine ecosystem responds to short-term heat waves and how it may react to the long-term temperature increases that are expected in the ocean due to the changing climate.
        “We think these heat waves will happen more frequently in the future, so it’s important to understand how the ecosystem responds to them,” she said. “We’re also interested in whether the response to this heat wave will give us insight into the general warming trend.”
        The expedition – which includes scientists from the Woods Hole Oceanographic Institute, Wellesley College, University of Massachusetts at Dartmouth, and the National Oceanic and Atmospheric Administration – is part of a long-term ecological research project funded by the National Science Foundation. Its aim is to compare how variability in the environment affects the ecosystem, from microscopic plankton to fish.
        “From our ongoing study we’ve learned that there are two different kinds of water out there – cold, nutrient-rich water that supports a lot of fisheries production, and warm, less-productive water,” Rynearson said. “We’re interested in the balance between how long the waters are warm and nutrient-poor versus cold and nutrient-rich.”
        The researchers will collect data along a transect from Narragansett to Martha’s Vineyard and then southward about 100 miles to an area at the edge of the continental shelf where the water is about 5,000 feet deep. Along the way they will take water samples at various depths to evaluate how much plankton is in the water, the rate of photosynthesis, and the rate that tiny marine animals called zooplankton are feeding upon tiny marine plants called phytoplankton.
        “We’ll also be looking at what species of phytoplankton and zooplankton are out there, because there seem to be differences in the community when you have cold, nutrient-rich waters versus warm, nutrient-poor waters,” said Rynearson. “We’ll ask, are we still seeing a summer community of marine life out there or is it too late in the year for that.”
        The research team also aims to gain a better understanding of the marine food web by studying the links between the tiniest creatures and the forage fish that are fed upon by the top predators in the ocean and captured in local fisheries.
        “We’re probing a part of the food web that’s not well understood in terms of the transfer of energy or the response to climate change,” Rynearson said. “That part of the food web is a bit of a black hole, and we want to shine some light in there.”

Thursday, October 8, 2020

Volunteers find Rhode Island's rarest turtle at new sites

        A pilot project using volunteers to scout for new populations of Rhode Island’s rarest turtle, the diamondback terrapin, turned up 15 new sites where the turtles have been confirmed. But despite the new populations, the biologist who led the project said the state’s terrapins are no less threatened than they were before the new populations were discovered.
        Herpetologist Scott Buchanan, a wildlife biologist at the Rhode Island Department of Environmental Management, said that prior to 1990, when a population of terrapins was discovered in Barrington, “no one had seen a terrapin in Rhode Island in many years.” Additional populations were
Diamondback terrapin (Todd McLeish)

discovered elsewhere in the state in the past decade, and when Buchanan was hired in 2018 and began asking around, he heard a number of unconfirmed reports of terrapins being observed elsewhere in Rhode Island.
        "That led me to think that they’re probably more widespread in the state than the narrative would lead us to believe,” he said.
        So he examined maps to identify “reasonable places” where he could send volunteers on a regular basis to see if they could spot the terrapins, the only turtle in the region that lives in salt marshes and brackish waters. Four volunteers each visited two to four sites twice a week from late May through mid-July, and an additional volunteer surveyed a dozen sites. During each visit they scanned the water with binoculars for three 5-minute periods and counted any turtle heads they observed.
        The discovery of 15 new sites was a revelation to Buchanan.
        “What it means is that they are much more widespread than we had thought,” he said. “It’s encouraging from a conservation standpoint, but at many of these sites, we have little or no information about how many turtles may be there, whether they are successfully breeding, or whether they are established populations. We don’t want to be overconfident or get too comfortable with the fact that there are multiple sites containing the species.”
        Most of the newly discovered terrapin sites are in coves along mid and upper Narragansett Bay. They’re still mostly absent from the lower bay, according to Buchanan.
        “What we’re seeing now is probably a shadow of their former distribution and abundance,” he said. “They’re out there, that’s excellent, but we know there’s lots of places they don’t occur. All the evidence suggests that they’re still absent from many places where they were historically present. And the types of abundances that we’re documenting are probably far less than historic abundances.”
        Buchanan speculated that the newly discovered populations in the upper bay may be the result of dispersal from the Barrington population, which has grown to number in the hundreds because of extensive conservation efforts.
        Despite the success of the survey project, Buchanan is still concerned for the state’s diamondback terrapins. Most terrapin eggs are consumed by what he calls “human-subsidized predators,” including coyotes, raccoons, skunks, and dogs. Terrapins are also at risk of being illegally collected for the pet trade, which is why he prefers not to reveal the location of the newly discovered sites. They also face drowning in crab traps, injury from being struck by boats, and automobile strikes as females cross roads on their way to their nesting territories.
        “The big threat, though, is sea-level rise and salt marsh decline,” he said. “They’re an obligate salt marsh species; if sea level rises and marshes disappear, they don’t have a chance. That’s something I’m especially worried about over the next 10, 20, 30 years along the Rhode Island coast. Salt marshes are critical as a source of food and a place where they overwinter and take shelter, especially the juveniles and hatchlings.
        “This new information we have is very encouraging, but it doesn’t mean we should let our guard down. They’re still a species that warrants conservation, even without sea-level rise. We must remain vigilant.”
        Having identified the location of additional terrapin populations, Buchanan hopes to prioritize those sites for future conservation efforts, modeled after the successful nest-protection and monitoring efforts in Barrington.
        “Knowing where they are, there are lots of small steps you can do to improve their conservation,” he said. “Things like small-scale habitat management, create barriers to keep them off busy roads, public outreach to ensure boaters use caution, adapt local pot fishery management.”
        The success of the pilot project to identify new diamondback terrapin populations has inspired Buchanan to double or triple the effort next summer at numerous additional locations. He also hopes to continue the project for many years to eventually be able to identify population trends at each site. He will be seeking additional volunteers this spring to survey coastal sites around the state in June and July. Those interested in volunteering should contact Buchanan at

The story first appeared in on October 5, 2020.