Blogs from Powdermill Nature Reserve

Powdermill Nature Reserve is Carnegie Museum of Natural History’s environmental research center. Located 55 miles southeast of Pittsburgh in Rector, Pennsylvania, Powdermill is a field station and laboratory where researchers do long-term studies of natural populations in western Pennsylvania. In addition to being positioned for Appalachian-specific studies in ornithology, ecology, invertebrate zoology, and botany, Powdermill is a great place to spend a fun-filled day outdoors with the family.

December 14, 2020 by wpengine

Oh deer, that’s a lot of parasites!

by Andrea Kautz

When a permitted hunter harvested a deer from Powdermill Nature Reserve in mid-November, I took the opportunity as an entomologist to inspect the hide for parasites. I was not surprised to find deer ticks and deer keds on the animal, but I was surprised by how many parasites there were, and the presence of two additional species of ticks not previously known from Powdermill.

Deer ticks (Ixodes scapularis) are infamous to most Pennsylvanians as the main vectors of Lyme disease. Over 300 deer ticks were found on this single deer, so that should give you an idea of how they can be so abundant, especially in areas with high deer densities. Adult females (Picture 1) were mostly found attached to the skin, in the process of becoming engorged with blood. Many adult males were also found on the deer, but since they don’t require a blood meal, what were they doing on a host? It turns out, a deer is a great place to locate a mate! While the female is attached for days feeding on blood, a male can easily locate and mate with her by inserting his mouthparts into an opening on her ventral side. Many of the females removed from the deer had a male attached (Picture 2).

female deer tick with male deer tick attached

Deer keds (Lipoptena cervi) are sometimes called tick flies because of their resemblance to ticks (both are flattened dorsoventrally), but they behave rather differently. Keds move much faster than ticks, and don’t remain attached for long periods of time while feeding. They are indeed true flies, in the same group of insects as the typical house fly, but they remove their wings once they locate a host, to make it easier to move within the dense hair. The adult females and males both feed on blood, and the female carries one larva at a time internally, giving birth to a mature larva ready to pupate. This is rare among insects, which typically lay many eggs at one time. About 450 keds were collected off this one deer, so the strategy seems to be working for them!

Winter ticks (Dermacentor albipictus) are closely related to the more familiar American dog tick (Dermacentor variabilis), but have a different life cycle. While most ticks utilize different hosts throughout their life cycle (feeding on three different animals as a larva, nymph, and adult), winter ticks spend their whole life on a single host, most commonly a deer, elk, or moose. They can be a serious problem for moose when infestations are severe. Three males of this species were collected off the deer. Although the winter tick has a broad distribution across North America, this trio represents the first Powdermill record.

The fourth and final parasite recovered from the deer was a single female Lone Star tick (Amblyomma americanum). Easily recognized by the white dot on the back of adult females, Lone Star ticks are found across the eastern U.S. and use a variety of mammals and birds as hosts. This is our first time encountering this species at Powdermill as well!

Penn State is conducting a citizen science project called PA Parasite Hunters to learn more about deer parasitology and vector-borne diseases, so the keds and ticks we collected will be sent there in order to contribute to these important studies.

Andrea Kautz is a Research Entomologist at Carnegie Museum of Natural History’s Powdermill Nature Reserve. Museum employees are encouraged to blog about their unique experiences and knowledge gained from working at the museum.

Bobcats

With winter approaching, visitors to Powdermill Nature Reserve can anticipate seeing the tracks in the snow of one of our most splendid residents, the bobcat! These wild felines do not hibernate, rather they remain very active in winter because of their high metabolism. Although they are commonly photographed on trail cameras at Powdermill Nature Reserve, bobcats have excellent vision and hearing and are unlikely to show themselves to people. The stealthy and efficient predators are found state-wide, and the range for the species known scientifically as Lynx rufus stretches across the North American continent from southern Canada to northern Mexico.

This adult female was photographed in late October, but photos do not really capture the full beauty of these animals. Image credit: John Wilkinson.

Bobcats are known to walk on top of fallen logs to move silently through the understory. Adults weigh up to 20 pounds, feed mostly on rodents and birds, but are capable of taking small fawns and perhaps even yearling deer. Bobcats are highly adaptable and do well even in close proximity to humans and coyotes. In our area, males wander over areas as large as 10 square miles, territories that span the smaller territories of several females. Bobcats are protected except for a brief trapping season in winter. Their coats are highly variable, and pelts are considered prime in winter, and more valuable when spotted. The highest quality, large pelts from the Rocky Mountains may sell for as much as $900. However, luckily for our cats, the market here is unlikely to provide $40 for a pelt, which will keep them safe from most trappers.

John Wenzel is the Director at Powdermill Nature Reserve, Carnegie Museum of Natural History’s environmental research center. Museum employees are encouraged to blog about their unique experiences and knowledge gained from working at the museum.

The Christmas Bird Count During an Irruption Year

Since 1900, the National Audubon Society has hosted the Christmas Bird Count (CBC), a fun day for birders and bird watchers of all skill levels to get outside and count everything they see and hear within a designated count circle. The CBC was started with the purpose of creating a new way of censusing winter birds. Before binoculars and optics were widely available, people used shotguns during a competition to see who could bring back the biggest pile of birds and mammals. In 1900, conservationists developed a non-destructive way to tally what they saw, and the Christmas Bird Count was born. The CBC’s initial 25 count circles have blossomed into coverage across the continent, in Central and South America, and to the Pacific Islands.

Each year, Powdermill Nature Reserve sponsors the Rector, PA Christmas Bird Count. This year, with some extra pandemic-related safety precautions, an intrepid group of local birders will canvass a 15-mile diameter circle centered just a bit north of Powdermill on Sunday, December 20. Upcoming counts promise to be interesting and exciting locally and across much of North America due to the irruption of many species of “winter finches.”

So, what is an irruption and what birds might we expect to see during an irruption year? Irruptive migration happens most often when there’s a change in food availability over much of a species’ normal range. It’s less predictable than the annual migration that we observe every spring and fall, and often happens in a cyclical pattern, reflecting normal changes in abundance of food items. Species that breed in the far north and winter generally farther north than Pennsylvania are those most likely to be irruptive migrants. When there is a poor seed crop, birds that eat things like conifer seeds, such as Pine Siskins, Red-breasted Nuthatches, and Evening Grosbeaks, as well as birds that prey upon small seed-eating animals, such as Snowy Owls, are often seen south of their typical range. This year has already proven to be a major irruption year and the season has barely begun!

At the beginning of September, we started to see Red-breasted Nuthatches at Powdermill in higher numbers than in previous years. They were followed in early October by large flocks of Pine Siskins, small finches that look a bit like streaky goldfinches. Although many remain in the area, quite a few siskins continued south and are currently flocking to feeders in the Carolinas and beyond! Even more exciting was the influx of Evening Grosbeaks, which first appeared in mid-October. This species’ population is in steep decline: these birds used to be commonly seen here in the winter until about 30-35 years ago, but now visit during only the biggest irruption years.

Northern Saw-whet Owl. Photo credit: Catherine Werth

Northern Saw-whet Owls are a species that we generally see each year, but this year banders are catching more than usual. One evening at Powdermill the team caught eight individuals, three of which were foreign recaptures! (This term refers to birds that were banded and recaptured at different banding stations. The three owls from that evening came from northeastern Pennsylvania, southeastern Ontario, and, for a bird initially banded four years ago, western Virginia.) Even familiar and common species that we see year-round but that have ranges that extend far north, such as Black-capped Chickadees and Purple Finches, are being seen in higher numbers this year.

What species can we expect next? Red Crossbills and Common Redpolls haven’t been reported in the Powdermill area yet but are creeping ever closer, and if we’re really lucky perhaps we may even spot White-winged Crossbills, Pine Grosbeaks, or Hoary Redpolls. So, keep your eyes peeled, your ears primed for unfamiliar calls, your binoculars polished, and a field guide nearby, and you may have a spectacular Christmas Bird Count season!

For more information about the Christmas Bird Count, please visit: https://www.audubon.org/conservation/join-christmas-bird-count

And for a fun kickoff to the Christmas Bird Count season, Powdermill avian researchers, along with colleagues and a very special guest, will be hosting a watch party of the movie The Big Year the evening of December 18. For more information and to register: https://carnegiemnh.org/event/the-big-year-watch-party/

Annie Lindsay is the Bird Banding Program Manager at Carnegie Museum of Natural History’s Powdermill Nature Reserve. Museum employees are encouraged to blog about their unique experiences and knowledge gained from working at the museum.

One man’s trash is another man’s weather instrument

A piece of debris was recovered by staff Friday afternoon while hiking along Powdermill Run at Carnegie Museum of Natural History’s biological research station, Powdermill Nature Reserve. What initially looked like nothing more than a pile of orange plastic garbage turned out to be something much more exciting! It was actually the remains of a weather balloon carrying a recording instrument called a radiosonde.

Powdermill Run, where the instrument was found. Thank you to Bobby Ankney, Maintenance Manager at Powdermill, for wading across the stream to recover it!

These devices are deployed by the National Weather Service in order to gather data about the upper atmosphere. A large balloon (5 feet in diameter) filled with helium or hydrogen gas carries the radiosonde upward at a rate of 1,000 feet/minute. The balloon can reach an altitude of over 20 miles before it expands (due to decreasing air pressure) to a diameter of 20-25 feet and pops. Temperatures at that height can be as cold as -130⁰F!

During its ascent, the radiosonde transmits data on temperature, pressure, humidity, and GPS location to a ground tracking antenna. GPS data indicate wind speed and direction during the flight. After the balloon pops, an orange parachute carries the spent instrument slowly to the ground, where it may be recovered and returned to the National Weather Service to be reused.

close up of weather balloon label that says "Harmless Weather Instrument"

The radiosonde we found was deployed in Pittsburgh on June 28, 2020. Pittsburgh is one of 69 stations in the contiguous United States and over 800 worldwide. Weather balloons at each station are typically deployed at the same time each day, 365 days a year. Data from these instruments are used in weather forecasting, air pollution modelling, and climate change research. While removing litter from the environment is a great thing to do anyway, in this case there was a bonus learning and recycling opportunity included. Cool!

From Collector to Director

Figure 1: CM 50625 – Rugosa Coral. Collected by M. Graham Netting in 1912. Coral body shape has a radial symmetry.

In 1912, eight-year-old M. Graham Netting unearthed 13 coral fossils within the city limits of Louisville, Kentucky. Later, as a 22-year-old Pitt student, he donated them to the Carnegie Museum of Natural History (Figure 1). When the Great Depression cut short his graduate studies at the University of Michigan in 1929, he returned to the museum as Assistant Curator of Herpetology, and worked his way up to Curator in 1932. In 1954, six months before turning 50, he was appointed Director of the Carnegie Museum of Natural History. Along the way, the Wilkinsburg native left an astonishing legacy that includes a steady growth in scientific collections, numerous wildlife dioramas in the Halls of Wildlife, and a mid-Appalachian field research station, Powdermill Nature Reserve. Upon his retirement in 1975, the Post-Gazette noted, “Long before it was “in,” Netting saw pollution of the air and water ravaging the land.”

Albert Kollar, Collection Manager of the of Section of Invertebrate Paleontology, re-discovered young Graham Netting’s horn corals while working on a multiyear review of the Bayet Collection. Netting’s label note did not provide any evidence for the stratigraphic unit that he collected from, but more on that later.

Figure 2: Carnegie Museum of Natural History exhibit reconstruction of an Early to Middle Devonian reef, 375 – 390 MYA. The reef shows Rugosa and Tabulate corals, a spiny trilobite about 18 inches in length and several straight cephalopods. Coral tentacles (shown in white) are illustrated in feeding mode. Both Rugosa and Tabulate corals went extinct at the end of the Permian Period.

Rugose corals are often called horn corals because many species have a horn shape. Horn corals attach to the sea floor by way of a sticky tentacle that protrudes from the base or curved end of the animal. Other invertebrate animals, such as brachiopods, attached in this position are described as sessile. The coral animal or “polyp” built its skeleton from calcium carbonate, a mineral formed from Bicarbonate and Calcium ions in seawater. The polyp tentacles or feeding polyp extend out from the top of the basic body for feeding (Figure 2). When the animal died, its soft tissues would have decayed and left behind the external hard mineral skeleton that fossilized.

Netting’s Louisville coral specimens are fossilized in a different way than similar corals from the nearby Falls of the Ohio middle Devonian fossil beds. His corals are lighter and fragile to the touch, conditions which gave Albert reason to compare Netting’s fossils to similar invertebrate paleontology corals from strata within the Louisville area. Sometime during or after burial, these horn coral skeletons were replaced by silica or quartz, a process known as silicification. The mineral silica can saturate a column of seawater when the seabed is overwhelmed with a large population of sponges. Sponge skeletons are composed of silica and when they die silica is added to a column or more of seawater. Volcanic eruptions eject silica into the atmosphere that eventually settles into the sea. Again potentially adding higher amounts of silica. Whatever the cause, Albert believes Netting’s corals were collected from the fossiliferous Middle Devonian age Jeffersonville Limestone, where the “lower foot of a “conglomerate” of reworked silicified Louisville Limestone” of Upper Silurian age is known to occur with silicified coral fossils (Conkin and Conkin, 1972).

Horn and Tabulate corals thrived in shallow seas forming diversified ecological reefs from about the late Silurian Period to the beginning of the Late Devonian epoch. During the Middle Devonian epoch roughly 400 Ma to 390 Ma years ago, reefs formed in central New York, southern Ontario, central Ohio, central Iowa, western Alberta, Canada, western Australia, and in Eifel, Germany.

Figure 3: Paleogeographic Map of the Middle Devonian Period – Kentucky is well south of the equator.

Louisville, during the Devonian Period, was centered in the southern hemisphere about 40 degrees south of the equator. Because of plate tectonics, the coral beds of Louisville would travel 5,500 miles over the next 390 million years to their present-day location of 38 degrees north (Figure 3). Today, fossil outcrops in the city limits of Louisville are difficult to find.

Figure 4: Graham Netting in his twenties.

When Netting retired as Director of Carnegie Museum of Natural History, he moved to a modest house next to Powdermill Nature Reserve. A seat was saved for him each Sunday at the reserve’s weekly nature talk. In 1996, he passed away. Steve Rogers, Collections Manager for the Section of Birds, recalls sipping fresh lemonade on Netting’s back porch in 1981. According to Rogers, Netting was reflective and humble. The fossil collector who became a museum director had a habit of rubbing his chin while listening to someone speak. When asked about his legacy, Rogers replied, “He was more instrumental in forming Powdermill than anyone. He had an amazing ability to be a part of a team that got things done.”

Figure 5: Graham Netting at Retirement in 1975.

As Netting prepared to step down as director in 1975, he said, “These great collections are a natural resource to answer questions about the life of the world.” On a recent day, I saw two children jumping up and down in front of the Glacier Bear diorama in Hall of North American Wildlife on a family visit to the museum. When one of the children asked, “what’s a diorama?” I thought about Graham Netting, smiled, and encouraged their engagement with the life of the world.

Many thanks to Xianghua Sun, Carnegie Museum Library Manager, Marie Corrado, Carnegie Museum Library Clerk, Stephen Rogers, Collections Manager for the Section of Birds, and John Wenzel, Director of Powdermill Nature Reserve for help researching this post.

Joann Wilson is an Interpreter in the Education Department at Carnegie Museum of Natural History and Albert Kollar is Collections Manager for the Section of Invertebrate Paleontology. Museum employees are encouraged to blog about their unique experiences and knowledge gained from working at the museum.

A Bumble’s Blog and Bumble “Weee” Catapult Craft

Wander outside in the spring and summer and I bet you will bump into a busy bumble bee bumbling among the wildflowers. Bumble bees (Bombus sp.) are rather rotund, fuzzy bees usually with black and yellow-orange stripes. Unlike the famous honey bee that hails from Europe and Asia, most bumble bee species are native to our area. Bumble bees have small underground colonies with a loose social system, compared to that of a honey bee. While bumble bees produce honey, it is in small quantities and certainly not enough to share on an industrial scale. Still, these fuzzy bumbles play an important role as pollinators of local wildflower populations and are even adapted to pollinate certain flowers!

This fashionable bumble bee is trying to squeeze into a little pair of white breeches! Duchman’s breeches (Dicentra cucullaria) to be exact. A bumble bee’s proboscis (tongue) is long enough to reach the nectaries within the nectary spurs or “pant leg” and the bee is strong enough to push open the flower petals to collect pollen.

This bumble bee is sipping nectar from squawroot (Conopholis americana). Bumble bees and flies are the typical visitors of this parasitic plant! Fun fact: bumble bees “buzz” pollenate, which means they vibrate their bodies, effectively knocking pollen down into the flowers they visit.

Upon observing the flight of a bumble bee, I have noticed that while they are strong flyers, they are not the most graceful. Sometimes they miss their mark and land on a chunk of moss instead of the flower. However, they just take that moment to rest their wings before firing up their little motor and buzzing off into, hopefully, the next flower. Their rather clunky flight pattern gave me an idea for a fun activity to help young children learn about pollinators (and sneak in a STEM activity): The Bumble “Weee” Catapult! See below for assembly instructions:

Materials

3 pipe cleaners

Paper

Pen or pencil

Coloring supplies

Scissors

Recycled egg carton

Recycled plastic spoon

4-5 large Rubber bands

Let’s dismiss the idea of launching real bumble bees and begin building the bee puppet 😉. Pick 3 different colors of pipe cleaner. Feel free to go with traditional bee colors or mix it up!

1. For the body, twist together two pipe cleaners.

2. Wrap the twisted pipe cleaners tightly around a pen or pencil and slide it off.

3. Tuck the loose ends inward and tighten up the coils on the end you would call the head.

4. For the wings, shorten the remaining pipe cleaner by 1/3, then loop it under one of the coils of the bee’s body.

5. Adjust the pipe cleaner for equal length on either side and twist at the base.

6. Roll in the loose ends to finish forming your wings, thus completing the bumble bee.

step by step photos of creating a bee from pipe cleaners

Next, build the catapult to help your bee puppet fly. The catapult consists of half of an egg carton, 4-5 rubber bands, and a recycled spoon. Tension energy is generated when the spoon is pulled back. The arm stores that energy as potential energy. Upon release, that potential energy is transferred to the object as kinetic energy, moving the object away from the arm. Pictured is the simplest catapult design with rubber bands holding the spoon, or arm of the catapult, in place. Feel free to design something more elaborate!

photo of catapult made from egg carton, plastic spoon, and rubber bands

Finally, the bumble bee needs a flower to land in! Draw a flower of your choice on a piece of paper and color it in. Many bees are able to see UV light, which means they are able see colors and patterns invisible to the human naked eye. Some flowers have nectar guides that really stand out to bees, so feel free to draw some nectar guides, or lines that point to the center on your flower targets to help guide your bumble bee!

Feel free to create as many flowers as you like and propel your little bumble bee into as many flowers as you can. Happy pollinating!

Sara Klingensmith an educator at Powdermill Nature Reserve, Carnegie Museum of Natural History’s environmental research center. Museum employees are encouraged to blog about their unique experiences and knowledge gained from working at the museum.

Oh deer, that’s a lot of parasites!

by Andrea Kautz

Related Content

Carnegie Museum of Natural History Blog Citation Information

Share this post!

Bobcats

Related Content

The Christmas Bird Count During an Irruption Year

Related Content

One man’s trash is another man’s weather instrument

Related Content

From Collector to Director

Related Content

A Bumble’s Blog and Bumble “Weee” Catapult Craft

Related Content

About

Get Involved

Bring a Group

Powdermill

More Information