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Pennsylvania's rivers and streams are home to a creature that has been attracting interest in the scientific community – the eastern hellbender salamander.
If the name is any indication, the large aquatic amphibian is not what you'd call attractive. The creature can be various shades of brown, gray or black with markings down its back and fleshy folds on its sides. It has a large, flat head, tiny, wide-set eyes, short legs and a tail. The hellbender can grow to about two feet in length and primarily feeds on crayfish.
Their highly permeable skin takes in oxygen from the river or stream in which they're living. For this reason, their presence is an indicator of environmental health.
Kurt Regester, Ph.D., of Clarion University Biology and Geosciences Department, has
been leading a long-term study of the eastern hellbender throughout the western two-thirds
of Pennsylvania. The purpose of the study is to assess the abundance, distribution
and health of hellbenders in our region.
During the past eight years, Regester and his students have captured and tagged hellbenders
by inserting a microchip, similar to the microchips offered at veterinary practices,
in the tail. Each year, the hellbenders are recaptured to obtain measurements of each
animal and collect swab and tissue samples from them.
One of the aims of the research is to learn demographic information – how many males,
females and juveniles are present, how many offspring are being produced, and how
many hellbenders survive from year to year.
In addition to demographics, Regester and his students study the health of each animal in the population. There are two infectious pathogens for which they have continually tested, including the fungus Batrachochytrium dendrobatidis, or Bd for short, and a virus called ranavirus.
The good news is that when the hellbenders are recaptured and scanned for a microchip from year to year, Regester recognizes them. In other words, a large percentage of the population that has been tagged for research survive from year to year. Regester said 60 to 70 percent of the animals they capture at their sites are animals that have already been tagged with a microchip.
On one of the research team excursions this summer, Regester and his students captured a hellbender that never had been captured before. In order to capture the animal, they had to search the creek for suitable large, flat rocks. Hellbenders live under these rocks, but researchers must find the rocks with adequate openings for the hellbender to enter. Often times, these rocks are large and require two to three people to carefully lift the rock, while other people wait with nets to capture the creature.
"It's a young hellbender in beautiful condition," Regester said when the hellbender was being examined.
The hellbender was tagged, measured and weighed. The animal also was gently stroked
with a sterile swab, and a small piece of tail was preserved to test for the pathogens
of concern. Once the animal was examined and data and samples collected, it was returned
to its exact home in the water – a practice that is performed for each animal.
The hellbender that was captured was small, indicating successful reproduction there,
and was without marks or blemishes – unlike most of the older adult salamanders.
"The old ones, especially the males, have many old injuries and can appear really beat up," Regester said.
Regester explained that during the fall, males defend their home rock as a territory for mating, vigorously defending them from other males, noting that most males have scars and missing toes from combat, and that he's captured several with missing legs.
Through the research, they've also discovered that even if the hellbenders contract the fungal pathogen Bd, they show no symptoms of disease and are doing quite well, Regester explained.
Unlike Bd, those that test positive for ranavirus are never caught again, leaving
researchers with concern for those individuals and more research questions about the
consequences of infections by the virus, he said.
The good news is that ranavirus appears to have only affected about 5 percent of the
population. The bad news is it's not just an amphibian virus, so fish, turtles and
other animals that share this same environment may be infected as well, Regester said.
"We are working on figuring out which species are big players in disease processes and how hellbenders are getting infected," Regester said.
This is the conservation biologist's dilemma.
"A conservation biologist will always work to protect species and habitats before problems occur, but they often spend much of their time addressing an immediate problem, such as the threat of diseases to global amphibian populations," Regester said. "In some cases, it can be a race against time."
Another such problem can be siltation – a problem in which fine particles pollute the stream water, disturbing habitats filled with aquatic life. Samantha Sullivan, a 2013 Clarion University graduate who works as a water pollution biologist with the state Department of Environmental Protection in Pittsburgh, said her work deals with the impact gas drilling has on waterways. She came back to help Regester and his students search for hellbenders this summer.
"I absolutely love to do hellbending, as we call the work in the field," Sullivan said.
Sullivan said her work as a student in the field with Regester prepared her for her work with the DEP and is still relevant to her present work.
As biologists work to figure out why certain amphibians are disappearing, the population declines continue to occur in many regions of the world, Regester said. The good news is that for hellbenders in western Pennsylvania, populations are fairly large and generally healthy – giving us a responsibility for one of the remaining core populations of the species. Regester says that hellbenders in the Midwest and our neighboring states are not faring well, so he's happy that the amphibians seem to be thriving here.
"The bottom line is that although our hellbenders appear to be doing well, we now have even more questions about these fascinating animals and a renewed commitment to conserve them here in Pennsylvania," Regester said.
Other projects
Regester also is associated with a handful of other projects in Pennsylvania.
PARS
The Pennsylvania Amphibian and Reptile Survey makes everyday citizens scientists in the field. The survey is conducted when everyday people take photographs of amphibians and reptiles, collectively known as herps, while outside enjoying nature. These volunteer participants then upload their photos to a publically accessible database on the Pennsylvania Herp Survey site: www.paherpsurvey.org.
In addition to uploading a photo of the animal they've found, participants are asked to fill in as much basic information as possible, including the county where the herp was located, the time it was located, the number of animals seen, age, sex, air temperature, cloud cover, weather conditions, elevation and habitat. Once this information is submitted, a team of five experts confer to make certain the report is plausible and approve the finding. Once the information and photo are approved, the findings live in the database.
The purpose of the survey is to determine where herps live in the state, if any of
animals are making a comeback in specific counties, or if their population is spreading
to other counties, Regester explained.
"You can't conserve an animal if you don't know where it lives," he said.
Regester first learned about this project at a local Audubon Society meeting, decided
to get involved and is now serving as the Clarion County coordinator for the project.
The information is invaluable to a conservation biologist.
"I think it's good to know how things are changing," Regester said.
In the two years since the project launched, there have been 1,350 registered participants who have recorded 98,000 records, which is encouraging to Regester.
"These are people who just care about the critters," he said.
This project is between the Mid-Atlantic Center for Herpetology and Conservation and the Pennsylvania Fish & Boat Commission with additional funding from the Department of Conservation and Natural Resources, Wild Resource Conservation Fund.
Newt study
Regester's work with PARS also led him to ask representatives of the Mid-Atlantic Center for Herpetology and Conservation if they would like to partner, using some of the active PARS volunteers, for a statewide sample study of the eastern red-spotted newt.
The study involves 45 recruited PARS volunteers who are gathering skin swab samples and very small tail samples from newts in the 67 counties across Pennsylvania. The samples are required to discover if the newts have any of three pathogens, including Batrachochytrium dendrobatidis, ranavirus and a new fungal pathogen called Batrachochtrium salamandrivorans.
Regester said for one person to take all of the samples, it would be very time consuming. He knew he needed a minimum of 30 people to cover the state's 67 counties. He has 45 volunteers and will get 1,500 samples back after volunteers collect all of the samples, starting in the spring and ending in the fall. The volunteers will keep their samples in a freezer until they are sent to Regester.
The volunteers were trained at a PARS meeting in March at the Elk County Visitor Center. The training covered how to collect the samples in a noninvasive way. Those who were trained could already identify the newts, he said. At the training, volunteers were given their sampling kits.
This study also is an opportunity for two different fields of biology to come together. When the samples are returned to Regester, they will be processed at Clarion University by assistant professor of biology Helen Hampikian, Ph.D., and her students. Hampikian is a molecular microbiologist.
"Helen and her students will have a lot of work," Regester said.
Regester said he and Hampikian hope to have the students trained in each area of the study with students training citizen scientists and learning lab techniques.
"It's cool that we can combine our expertise," Hampikian said. "It's awesome for the students."
Hampikian said once the samples start coming in this fall, she and the students will
begin the labor-intensive work to extract DNA from the samples to determine if the
two fungal pathogens and the viral pathogen are present.
Initially, Hampikian will spend time in the lab training her students, but once they
are confident with the process, they can work on the project in their spare time.
"I'm hoping to be able to recruit more students to work on it," Hampikian said.
Once the DNA is extracted, Hampikian and her students will go to the Barnes Center to use a special machine that amplifies the pieces of DNA. Hampikian isn't sure how long it will take to process all of the samples, but she expects to have results by next summer.
Regester hopes he can begin to publish the findings of the study sometime next summer, which is something Hampikian said is exciting for the students. They'll gain experience with research manuscripts and have the opportunity to present findings at conferences.
The project is supported by a grant from the Pennsylvania State System of Higher Education, facilities at Clarion University and the Barnes Center for Biotechnology Development, and a generous donation from a PARS member.
Regester believes the project was a good fit for the PASSHE grant because it is a research project in its truest form with citizen scientists and the involvement of students who are being cross trained in the field and lab.
"The science is so much better when you can combine the disciplines," Regester said.
Rattlesnake study
Along the same lines of Regester's hellbender and salamander work, Regester has been spearheading a study of the eastern massasauga rattlesnake, which has a presence in Western Pennsylvania.
The eastern massasauga is prone to a fungus which disfigures the reptile's face, making it impossible for them to eat. They also will collect demographic information on the snakes.
He will be working with Clarion University alumnus Howard Reinert, Ph.D., ('78, M.S. in biology) on the project. Reinert is a professor of biology at the College of New Jersey. Matthew Allender, Ph.D., of the University of Illinois, will complete the lab work for the project.
Vernal pools study
Regester also will begin a two-year study in 10 different state parks to survey the types of species living in vernal pools.
Regester explained that vernal pools are often temporary pools of water that have
a short life before they dry up. However, before they dry up, vernal pools often support
different species of animals such as frogs and their tadpoles.
The parks included in the study are Bendigo State Park in Elk County, Chapman State
Park in Warren County, Clear Creek State Park in Jefferson County, Cook Forest in
Clarion and Jefferson counties, Laurel Hill State Park in Somerset County, Maurice
K. Goddard State Park in Mercer County, Nescopeck State Park in Luzerne County, Pine
Grove Furnace State Park in Cumberland County, Promised Land State Park in Wayne County
and Swatara State Park in Lebanon County.
The study is supported by the Wild Resource Conservation Fund which is established by the sale of wildlife license plates in the Commonwealth of Pennsylvania.