Showing posts with label Delaware. Show all posts
Showing posts with label Delaware. Show all posts

Saturday, 16 August 2014

Killer ranavirus threatens frogs, turtles in Delaware-The disease blamed for a worldwide decline in amphibians has been spreading to reptiles.- via Herp Digest


Molly Murray, The (Wilmington, Del.) News Journal 7:55 p.m. EDT June 2, 2014

A virus partially blamed for a worldwide amphibian decline has made its way to Delaware, killing tadpoles and raising fears it will spread to reptile species.
The ranavirus, a type of virus that affects cold-blooded species, has been found in wood frog tadpoles in all of Delaware's counties and eight in Maryland. And there is concern it could impact iconic reptile species like the Eastern box turtle or endangered species like the bog turtle.
"Of 23 Delaware ponds tested in 2013, ranavirus was detected in 14 – 61 percent – and amphibian die-offs were recorded for two of those during the sampling period," said Holly Niederriter, wildlife biologist with the state's Species Conservation and Research Program.
In addition, a dead bog turtle found three years ago in Delaware likely died from a predator attack but it was infected with ranavirus, herpes and mycoplasma, she said.
Tracking the potential impact on relatively secretive turtle species is difficult, why is why Niederriter has been out again this year re-sampling ponds. She is finding similar signs of the virus.
She said that infectious diseases such as ranavirus – which is likely spread by contact with water or sick or dead tadpoles – are a large cause of the worldwide amphibian decline.
The disease is found throughout the United States in both frogs and turtles but it has not been found in birds or mammals. With some tadpole frog species, the mortality rate is as high as 99 percent.
"The virus can also be spread via water, in soil and on the boots, nets and gear of humans," Niederriter said.
The ranavirus was identified in Maryland in 2001 in Prince George's County, said Scott Smith, a wildlife ecologist with the Maryland Department of Natural Resources.
Delaware officials began looking for the disease in wooded ponds last year as part of a regional effort, prompted by a turtle die-off discovered as part of a study on the impact of a proposed new highway in the Maryland suburbs of Washington.
A researcher at Towson University put radio transmitters on Eastern box turtles to see how they would fair if they were moved to new locations as part of a road construction mitigation project.
But the transmitters turned up something unexpected.
"They'd be sick one day and dead the next," Niederriter said.
Smith said the researcher lost both his control site and his two test plots to ranavirus in the study that took place from 2008 to 2011.
One reason for the concern, Smith said, is that box turtles are long-lived and have reproductive strategy that differs from frogs. Frogs typically lay eggs in woodland ponds by the hundreds.
But box turtles, while laying several clutches of eggs, may only lay three to eight at a time.
Smith said with frogs, especially wood frogs, the disease seems to have highest impact on the tadpoles but doesn't kill adults. That means the adults, which typically live five to eight years, can return to breed again the following year.
There are species, like bullfrogs, that appear more resistant to the disease, he said.
So far, researchers believe the disease in our area has the greatest impact on wood frogs and spotted salamanders. No one is certain how it spreads from pond to pond, though there is some thought that other wildlife may spread it, including bullfrogs, which can travel three miles to breeding pools.
Researchers have found that one day a pond can seem fine and then the entire wood frog tadpole population can be wiped out in as little as five days.
Over several days in late May, Niederriter and research assistant Christine Tilton set out to sample wood frog tadpoles.
The two scientists waded into slightly less than knee deep water at Blackbird State Forest. In March, they marked the areas where wood frogs laid their egg masses with orange survey tape.
Last week, they took long-handled nets and swept through the leaves and water in the survey area, searching for inch-and-a-half long tadpoles.
They needed 30 animals, which they collected in a bucket and took back to a test site in a cleared area in the woods.
"They have to be a certain age," Niederriter explained. The telltale sign is that the tadpoles are starting to develop legs. At this stage of development, the tadpoles may even show signs of the disease – red splotches.
For this study, the tadpoles are killed with a numbing agent before being examined because they must be sent out to a lab for positive confirmation of the disease.
"This year we're finding die-offs in more of the ponds," Niederriter said.

Wednesday, 3 October 2012

Florence Lenahan Killed By Falling Llama In Ohio


DELAWARE, Ohio — An Ohio sheriff's department says a woman has been struck by a pet llama that was trying to greet her and has died.

A report by the Delaware County Sheriff's Office says former coroner Florence Lenahan apparently had a heart attack as she was being taken to a hospital.

The report says the 74-year-old Lenahan called for help Tuesday after a llama named Baby Doll slipped on wet grass while running to greet her and knocked her down, causing her to hit her head on concrete. It says there's no evidence the llama was acting maliciously.

Lenahan's family is working with the Delaware County Humane Society to find homes for the animals on her property.

Thursday, 30 August 2012

Climate Change Could Increase Levels of Avian Influenza in Wild Birds

ScienceDaily (Aug. 29, 2012) — Rising sea levels, melting glaciers, more intense rainstorms and more frequent heat waves are among the planetary woes that may come to mind when climate change is mentioned. Now, two University of Michigan researchers say an increased risk of avian influenza transmission in wild birds can be added to the list.

Population ecologists Pejman Rohani and Victoria Brown used a mathematical model to explore the consequences of altered interactions between an important species of migratory shorebird and horseshoe crabs at Delaware Bay as a result of climate change.

They found that climate change could upset the carefully choreographed interactions between ruddy turnstone shorebirds and the horseshoe crabs that provide the bulk of their food during the birds' annual stopover at Delaware Bay, a major estuary of the Delaware River bordered by New Jersey to the north and Delaware to the south.

Climate change-caused disruptions to the well-timed interplay between the birds and crabs could lead to an increase in the avian influenza infection rate among ruddy turnstones and resident ducks of Delaware Bay, the researchers found. Because Delaware Bay is a crossroads for many bird species traveling between continents, an increase in the avian infection rate there could conceivably help spread novel subtypes of the influenza virus among North American wild bird populations, according to Rohani and Brown.

Continued: 
http://www.sciencedaily.com/releases/2012/08/120829093850.htm 
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