UD graduate student studies snow leopard population in Tajikistan

December 19, 2012 under CANR News

snow leopard in TajikistanAs he lay in a bathtub, seeking shelter from the barrage of mortar attacks just outside his building, Shannon Kachel realized that his summer of studying snow leopards, ibex and Marco Polo sheep in the desolate mountains ranges of Asia was over.

Spending the season in the Pamir Mountains region of Tajikistan to study wild ungulate -– or hooved mammals — and snow leopards to determine all the variables surrounding the species and possibly get an idea about their population sizes, Kachel, a University of Delaware graduate student working with Kyle McCarthy in the Department of Entomology and Wildlife Ecology, went into the city of Khorog to resupply for the final month of research and found himself caught in the middle of a fight between the Tajikistan central government forces and what the government deemed was an illegally armed group.

Kachel said that he wanted to stay and continue with his research but he knew that he had to leave.

“I would have stayed because my read of the situation was that it was going to get better,” said Kachel. “But I don’t know that I would have gotten anything done.”

Luckily for Kachel, he had already set up enough cameras in the region – cameras designed to record the movement of the various animals — that he was confident he had enough material for his study.

Researching two distinct areas of the Pamirs, Kachel placed one set of cameras in a location where the government allows trophy hunting of wild ungulates while informally managing the population for sustainability.

He also set up cameras in a section where it is illegal to hunt the animals and where there is no regulation of the species, but where poaching and overgrazing still threaten the wildlife.

“What I’m doing is comparing those two sites, one for the availability of the ungulate prey, but then the snow leopard populations, as well,” said Kachel.

While hunting and poaching is a concern, with the snow leopard population number dropping precipitously over recent decades, Kachel stressed that his research is looking more at the impact pastoral communities have on the species.

“A lot of that population loss results from the typical poaching pressures that we think of from people going out and killing big cats but a bigger component is competition with pastoral people,” said Kachel.

He explained that as external government food subsidies dried up with the fall of the Soviet Union, it left an artificially high human population in the area based on what the environment could support. In this high and desolate region of the world, the people turned to livestock production and the killing of wild ungulates in order to sustain themselves.

snow leopard“The component that I’m addressing is more from the ecological perspective,” said Kachel. “The other side of having all these livestock on the landscape is that it reduces the amount of natural prey that’s available for snow leopards and it gets rid of all the forage available for, specifically in my study area, the ibex and the Marco Polo sheep.”

Thanks to funding from Panthera, a global wild cat conservation group, and help from the Tajik Academy of Sciences, Kachel spent June and July traversing the rugged terrain and eventually getting close to 80 cameras set up in an area about half the size of the state of Delaware. “We were hiking around a lot,” said Kachel. “Huffing and puffing in that high mountain air.”

He explained that the cameras “work based on heat and motion. So an animal that’s a different temperature from the background walks by and the camera starts shooting pictures.” Kachel said that since they used two different types of cameras for the study, they put out lures with the cameras to draw in the animals.

“Because the cameras function differently, we needed to make sure that any animal passing by was present long enough to get clear images,” said Kachel. “So we used the lure to draw them in and hold their attention. We need clear images so we can identify the individual cats.”

Kachel explained that he did this because “snow leopards are individually identifiable based on their spots, so we can use our observations of when, where, and how frequently individuals are caught by the cameras to build better population estimates that tell us more than a simple minimum count.”

The cameras, which were retrieved by a Tajik man once the violence ended, have already caught pictures of two snow leopard cubs, and were highlighted by Reuters and inBusiness Insider.

Kachel said that he is encouraged with the results he has gotten back so far.

“As far as getting these pictures is concerned, in some ways I’m actually really optimistic about how many pictures we’ve gotten back in terms of snow leopard outlook and the prognosis for the species,” said Kachel. “The global population estimate ranges from 3,500-7,000 animals and that’s a huge range. It could be anywhere in there, so for at least the trophy hunting site, to get the number of images that we’ve gotten back is encouraging to me.”

Kachel, who is 28, said that if these preliminary results are borne out, it would give conservationists another tool to protect snow leopards and their prey throughout their range.

Article by Adam Thomas

Images courtesy of Panthera and Shannon Kachel

To watch a video of the snow leopards, check out the article on UDaily.

Share

UD Embarks on New Study Abroad to Cambodia, Vietnam

December 18, 2012 under CANR News

January 2013 marks the beginning of an exciting journey for 12 adventurous students at the University of Delaware. In their Winter Study Abroad session, these students will embark on the University’s first expedition to Cambodia and Vietnam. The goal of this 27-day program is to give students the opportunity to explore the rich wildlife and unique history of Cambodia and Vietnam, while at the same time fulfilling two Wildlife Conservation courses: Conservation of Southeast Asian Wildlife and People and Wildlife of Southeast Asia. The students will venture on this journey with an Art study abroad program fulfilling–Indigenous Arts of Southeast Asia and Documentary Photography–led by Jon Cox, assistant professor of art.

The students will be blogging about their experience throughout winter session.

“All of our [conservation] programs have a human component, and look at how humans impact conservation. South East Asia has a long history, dating back much farther than most areas of the world,” says Jacob Bowman, associate professor of wildlife ecology, and one of the faculty members leading the study abroad session.

According to Bowman, these war-torn countries offer students an unusual view on culture and wildlife, as many of the region’s mountainous areas have been mostly untouched by humans (other than guerillas) throughout the war, thereby preserving the habitats of the indigenous animals.

“There are still tigers, elephants, leopards and a lot of large mammals left in some of these remote areas, partially because for a long time it was dangerous for people to go into these areas,” Bowman explains.

The program begins in Vietnam, where students visit ancient temples of Angkor Wat, journey through the Mekong River and the dated tunnels used in the Vietnam War. Next, in Cambodia, students will experience unique wildlife and learn first-hand about conservation issues. Students will study Cambodia’s history and people by visiting various locations, including sacred temples and the historical killing fields, where large numbers of people were killed after the Cambodian Civil War. It is from this visit to the killing fields that Bowman expects students to be the most affected.

“When you go there and see a tower of skulls from all the people that have been killed, it’s a powerful experience. Hopefully students walk away realizing how bad humans can be, and how we continue to not learn from our own historical mistakes.”

A strong conservation issue to be examined is how overpopulated countries over-hunt their wildlife, and how these countries could benefit from developing an eco-friendly balance. Says Bowman, “Because it [Asia] has such a large population, it tends to overexploit its resources. There is almost no wildlife here because of the economic dilemma. People care about the wildlife, but their situation prevents them from conserving. They are just trying to feed their families and survive day to day.”

While Bowman says the University supported his choice of studying in Cambodia and Vietnam, the group is still being careful in these areas. UD students will interact with students from The Royal University of Phnom Penh and will predominantly stay in hotels throughout the trip, as it is safer than camping.

Bowman, who along with Cox, has run numerous study abroad programs to Tanzania, Australia, and Antarctica, is very excited for this new trip, and for the students. “Being able to interact with the students in a way where you can get them thinking about things cognitively instead of just strict classroom assignments is very satisfying. If something happens, the group is small enough to talk about it.” He relates a story that on one of his trips to Africa, he came face to face with a lion at night. “Stuff like that is hard to put into words, but particular things happen on every trip, and that is what builds impressions.”

What Bowman really hopes each student walks away with is a new point of view. He hopes this journey will open their eyes about the challenges of conservation on an international arena, where they will witness a form of living very different from their own.

According to Carly Costello, a UD junior majoring in animal science and taking this in-demand program, “It’s all about the first-hand experience. I’m excited to experience another culture; everyday things that we think are ordinary are so different to them, and vice versa.”

Article by Samantha Walsh, UD Wildlife Conservation and Communication junior

Share

Beekeeping 101

December 17, 2012 under CANR News, Cooperative Extension, Events

Dr. Deborah Delaney, assistant professor and extension specialist, will be a presenter at a “Beekeeping 101″ workshop offered on Saturday, January 12 from 8am-4pm at Delaware State University’s Research and Outreach Center in Smyrna, Delaware.

Sponsored by the Delaware Beekeepers Association and Delaware State University’s Small Farms Program, this one-day course is a great intensive learning opportunity for anyone interested in the art and science of beekeeping. For more information or to register, contact Bill Leitzinger at e-mail – DEBeekeepers@gmail.com.

The cost for the workshop is $50 and includes lunch, a one year membership in the Delaware Beekeepers Association (a $20 value), handouts for each topic covered, and the popular beginning beekeeping book “The Backyard Beekeeper” by Kim Flottum, editor of Bee Culture magazine (list price $24.99). Married couples/life partners are welcome to both attend – and only pay for one person. (Only one book will be given out per family/couple who attend.)

Other workshop presenters include:

  • Bill Leitzinger, President, Delaware Beekeepers Association
  • Robert Mitchell, State Apiarist, Delaware Department of Agriculture
  • David Carter, Backyard Beekeeper & Experienced in Woodworking

AGENDA

8:00      Registration & Networking – Muffins, donuts, fruit, coffee, tea, juice, etc…

8:30      “Why Beekeeping is a Great Hobby”

8:45      “Essential Beekeeping Equipment”

9:45       BREAK

10:00    “Hive Management in the First Year of Beekeeping”

10:45    “Flowering Plants Important to Honey Bees”

11:30    “Inspecting, Feeding, & Placement of Your New Hives”

12:00    Lunch – sandwiches, fruit, dessert, & drinks provided

12:45    “The Secret Life of Honey Bees”

1:45      “Identifying Honey Bee Diseases & Pests”

2:30      BREAK

2:45      “Integrated Pest Management”

3:30      “Ask the Beekeeping Experts” – Panel of Beekeeping Experts

4:00      ADJOURN

DIRECTIONS: From Route 1 – Get off at the South Smyrna Exit. Turn right onto Rt. 13 North. At the next light, turn right onto Smyrna-Leipsic Road. Go ½ mile, see sign on right for Delaware State University – Smyrna Research & Outreach Center. (look for yellow “BEE MEETING” signs). The snow date is Saturday, January 19th.

Share

Jeffrey Smith recognized for excellence in entomology academics and research

December 14, 2012 under CANR News

Jeffrey Smith, a senior in the College of Agriculture and Natural Resources majoring in ecology and environmental science, received an Undergraduate Student Achievement in Entomology Award presented by the Plant-Insect Ecosystems section of the Entomological Society of America (ESA) at the ESA’s annual meeting in Knoxville, Tennessee.

The award included $1,500, which could be used towards travel expenses for the winning students to participate in the ESA meeting. Award winners must attend the ESA National meeting and participate by submitting and presenting a paper or poster.

“For me this award was as much about honoring the past work I had accomplished, which was both gratifying and deeply appreciated, as it was about enabling me to attend and present at the national conference, which was simultaneously humbling and inspirational,” said Smith. “While it felt great to be honored for what I have already accomplished, having the chance to learn about new topics, to meet new people, and to see the opportunities available to me in research was a much more valuable component of the award.”

The award was given to Smith for work he did in the summer of 2011, when he worked with Judith Hough-Goldstein, professor in the Department of Entomology and Wildlife Ecology who serves as Smith’s advisor and who nominated Smith for the award, as a summer scholar, which was funded by the United States Forest Service, the Undergraduate Research Program, and the Department of Entomology and Wildlife Ecology.

The research involved studying the host finding behavior of a small beetle, Rhinoncomimus latipes, used as a biological control agent for the invasive mile-a-minute weed. “Biological control of weeds is essentially the use of the natural enemy of the undesirable plant as a control method rather than chemical herbicides or mechanical control, such as weeding or mowing,” explained Smith. He said that mile-a-minute weed is native to Asia and was accidentally introduced to the United States.

Since its introduction, it has “become very weedy, overgrowing and out-competing desirable native plants.” The beetle, which is also native to Asia, was determined after years of testing to be host specific to the mile-a-minute weed.

“My specific project studied what behaviors influence how the beetle finds mile-a-minute in order to help improve the efficacy of the control program by strategically determining where to release the beetle,” said Smith. “I determined that this host finding behavior was a combination of both phototaxis, an attraction to sunlight and an attraction to chemical or visual cues given off by the mile-a-minute plant.”

Smith also presented on the topic twice prior to the national conference and his research was published in the Journal of Insect Behavior that can be found here.

Article by Adam Thomas

Photo by Brian Cutting

Share

Asters keep UD Botanic Gardens colorful through November

November 12, 2012 under CANR News, Cooperative Extension

Some of autumn’s pleasures are fleeting. Like the sight of migrating broad-winged hawks soaring on thermals in the September skies. Like the golden leaves of the ginkgo, which drop from the tree in a few days or sometimes mere hours. Like the big, orange, once-a-year occurrence of the harvest moon.

But other autumn pleasures – like asters – endure all season long. Asters start blooming at the same time as such early fall wildflowers as goldenrod and thoroughwort. But long after many other blooms have turned brown, the aster is still going strong.

Of course, no one species of native aster blooms straight through from September to November. Most bloom for a few weeks and then, as they die off, other varieties began to flower. Some of the native varieties that bloom the latest include aromatic and heath asters.

“It’s not unusual to see aromatic, heath and other species of asters blooming in late November,” says Sue Barton, an ornamental horticulture specialist with University of Delaware Cooperative Extension. “Asters continue to add a splash of color to the landscape in late autumn, when little else is blooming in Delaware.”

There are 33 native species and varieties of the genus Aster in Delaware, according to Bill McAvoy, a botanist with the Delaware Natural Heritage Program. Several of these varieties are classified as rare in the state. Asters are found in a wide range of habitat – woodlands, swamps, marshes, wet meadows and old fields. Some species are tall and bushy; others are groundcovers. Most prefer sunny conditions but some do well in shade.

Asters are tough and reliable, which is why they are popular with both home gardeners and commercial landscapers. “Asters – both natives and non-natives – are some of the easiest perennials to grow,” says Barton. “They don’t require much watering, fertilizing or other care.”

Doug Tallamy likes asters because they contribute to healthy local ecosystems. Asters are a valuable food source for a variety of pollinators, including native bees, honeybees, butterflies, beetles and flies, says Tallamy, chair of UD’s Department of Entomology and Wildlife Ecology and author of Bringing Nature Home: How Native Plants Sustain Wildlife in Our Gardens.

“As one of the latest blooming widespread plants, asters are very important as a carbohydrate energy source for butterflies, bees, beetles and flies,” says Tallamy.

If you’re looking for a good aster to plant in Delaware you couldn’t do better than talking to Jeanne Frett, a research horticulturalist at Mt. Cuba Center. A few years ago she conducted a performance evaluation of asters in conjunction with Victor Piatt, the center’s former trial area gardener.

The duo evaluated 56 different asters over a two-year period for such factors as color, bloom period, foliage quality, disease resistance and more.

Varieties that got top marks include smooth aster, prairie aster and calico aster. A late bloomer that scored well is the large-flowered aster. Some years, this aster may start in mid-October and finish by Halloween. Other seasons, it doesn’t flower until mid-November and then continues blooming past Thanksgiving.

You can see these varieties of asters – any many more – at Mt. Cuba. Public garden tours are held Thursdays through Sundays; registration is necessary. The University of Delaware Botanic Gardens also has a great selection of asters. Late bloomers there include Aster oblongifolius “Raydon’s Favorite,” a showy variety that sports a profusion of blue-lavender flowers with yellow centers.

Mt. Cuba Center is located at 3120 Barley Mill Road in Hockessin. For more information, call 239-4244.

The University of Delaware Botanic Gardens is located on the grounds of Townsend Hall off South College Avenue in Newark. The garden is open dawn to dusk daily and is free of charge. Parking is available at meters or by purchasing a parking permit for $3 online. To learn more, call 831-0153.

Article by Margo McDonough

Photo by Danielle Quigley

This article can also be viewed on UDaily.

Share

UD researcher offers the buzz on why bees, wasps are busy in autumn

October 9, 2012 under CANR News, Cooperative Extension

You buy a cider doughnut at the apple orchard and they quickly find you. Your kid opens a sports drink at the soccer field and they show up. You dine on the deck on a warm afternoon and sure enough, there they are.

This time of year, bees and wasps seem to be everywhere. Why won’t they buzz off?

University of Delaware bee researcher Debbie Delaney can’t clear the bees and wasps from your backyard barbecue but she can shed some light on why these insects are busy in autumn. Given how beneficial these species are to humans (yes, wasps, too) she hopes people will become more tolerant of their activity this time of year.

“Bees aren’t trying to sting you or ruin your outdoor fun,” says Delaney, assistant professor of entomology and wildlife ecology in the College of Agriculture and Natural Resources. “It’s just that autumn is a particularly important time for honeybees and native bees as they get ready for winter.”

In late summer and fall, worker bees labor long hours, collecting enough nectar to feed and maintain the colony throughout the winter. Bees visit flowers to obtain carbohydrates (nectar) and protein (found in the pollen).  Late-blooming flowers that feed the bees include asters, chrysanthemums, goldenrod and Russian sage.

“As the days shorten, the bees know it’s time to go into this food-gathering mode,” says Delaney. “If supplies run low during the winter, beekeepers can feed bees various sugary concoctions — for example, sugar syrup, corn syrup or granulated sugar in the form of sugar boards. But wild bees are out of luck in this regard. Their colonies may not survive if they didn’t make adequate preparations.”

For the most part, bees hunker down and stay in the hives all winter. On unseasonably warm winter days, they will come out to remove waste from their abdomens and the hive, clean themselves, and forage. Of course, there isn’t much to forage in the dead of winter so provisions gathered in fall are critical to the success of the hive.

While bees are busy getting ready for the season ahead, wasps are taking advantage of a brief, well-deserved retirement.

“In late summer and fall, when the queen wasp stops laying eggs, the worker wasps change their food-gathering strategy,” says Delaney. “Earlier in the season, the wasps were busy collecting insects – a protein source – for the colony’s young. But now they’re intent on getting sweets and carbohydrates for their own consumption.”

Adult wasps have just a few weeks to binge on carbohydrates before they die off at the first hard frost. They deserve some fun, considering the good that they do.

“I don’t think many people realize that wasps are beneficial insects,” says Delaney. “But they are true carnivores and engage in a lot of insect collecting earlier in the season. They are predators of a number of pest insects, including mosquitoes, flies and beetle larvae.”

Wasps that do enjoy a longer lifespan are the newly mated gynes (aka, queens). They over winter alone, awaiting the first signs of spring, which signals them to start the creation of their own nest.

Compared to wasps, there’s much more awareness of the critical role that bees play to human life. If honeybees disappeared, food would be scarce, as colonies stopped pollinating fruit, nut and vegetable crops. And if all 20,000-plus species of bees in the world were to disappear, the results could be catastrophic.

Here in Delaware, residents can thank honeybees and native bees for pollinating a cornucopia of crops, including apples, asparagus, blueberries, broccoli, cabbage, carrots, cantaloupe, cucumber, eggplant, peaches, pears, peppers, pumpkins, strawberries, tomatoes, watermelon and more, notes Delaney.

Plus, the honeybees share their honey with us, too. Delaney and her students pulled honey from the UD Apiary in late July and August and it’s now for sale for at the UDairy Creamery. This is the second season that UD honey has been available to the public.

Branded with the moniker “Dare to Bee,” the first harvest was golden in color and had a light taste, which reflects the fact that the bees obtained a lot of pollen and nectar from a stand of black locust trees near the apiary. The second harvest is darker in color and has a caramel flavor representing a blend of late season native and introduced species such as asters and knotweeds.

“Dare to Bee” honey sold out fast last autumn. If you’d like to try it, buzz on over to the UDairy Creamery soon. It’s located behind Townsend Hall on the university’s Newark campus. For store hours and more info, go to the website.

Article by Margo McDonough

Photo by Danielle Quigley

This article can also be viewed on UDaily.

Share

Now’s the time to watch migrating raptors, says UD’s Williams

September 27, 2012 under CANR News

If seeing a kettle of birds is on your bucket list, head to Hawk Watch at Ashland Nature Center or Cape Henlopen State Park ASAP. If this natural phenomenon isn’t on your bucket list, perhaps it should be.

“Kettle” is the word that birders use to describe a group of birds wheeling and circling tightly in the air on a thermal updraft, says Chris Williams, a University of Delaware associate professor of entomology and wildlife ecology. Nature photographer M. Timothy O’Keefe speculated that the term comes from the fact that these furiously flying flocks look like “something boiling in a cauldron.”

Your jaw is bound to drop the first time you see hundreds of birds swerving and soaring inside a thermal bubble as it rises aloft. (It’s still pretty jaw-dropping the sixth or sixteenth time you see it.)

Now’s the prime time to catch a kettle. That’s because broad-winged hawks are currently passing over Delaware on their fall migration to the neo-tropics. Although all raptors utilize thermals to make their flights more efficient, certain species, such as broad-winged hawks, are known to be frequent users of these air currents.

Large kettles of broad-winged hawks started showing up in Delaware in mid-September – more than 2,000 broad-wingeds were spotted at Ashland on Sept. 11 alone – and will continue through the end of the month.

“When it comes to the fall migration, my favorite species is actually the golden eagle,” says Jim White, associate director of land and biodiversity management for the Delaware Nature Society, which owns Ashland Nature Center. “The golden eagle is the ‘holy grail’ of fall bird-watching,” adds White. “But, in terms of pure spectacle, nothing beats the broad-winged hawk migration and the sight of hundreds and hundreds of hawks overhead.”

Long before the leaves turn or the autumnal equinox even occurs, the fall bird migration gets underway. “In August and September, songbirds migrate, beginning with hummingbirds and kingbirds and followed by warblers,” says Williams. “Slowly a parade of migrants work their way south, some leaving our area while others are coming in. Expect to see the shorebirds leave first followed by teal passing through and finally wintering waterfowl setting up shop.”

Now through October is peak season for the raptors – birds of prey, including hawks, eagles, falcons, ospreys and owls. However, every raptor flying overhead isn’t necessarily a migrant.

“Some raptors migrate south; others in the same species choose to overwinter here in Delaware,” notes White.  “For example, there is a pair of resident bald eagles that nests at Hoopes Reservoir. If you’re up on Hawk Watch Hill and see two bald eagles just monkeying around, flying low over Ashland’s Treetop Woods, then it’s probably these residents and not migrants. We train the Hawk Watch coordinator to exclude resident raptors from the counting records.”

The Hawk Watch sites are each staffed by a coordinator who is there to educate visitors as well as to count birds. Both programs are funded by the Delmarva Ornithological Society with additional support from other nature organizations.

Williams finds value in citizen-scientist initiatives such as Delaware’s Hawk Watch program. “These programs offer useful data for ornithologists,” he says. “Bird populations are dynamic and constantly in flux. No single researcher or team of researchers working alone could document the distribution and movements of so many fall migrants the way Hawk Watch efforts throughout the nation do.”

Of course, you don’t need to be part of a formal citizen-scientist program to track fall migrants. Just ask Ethan Harrod, a 5-year-old North Wilmington resident who counts birds with the help of his trusty field guide for young birders.

“Ethan sighted a red-tailed hawk on the Wilmington waterfront and he saw a sharp-shinned hawk fly over our backyard,” reports his father, John Harrod, who is manager of the DuPont Environmental Education Center in Wilmington. “He loves to try to id a bird and then check his field guide to see if he was right.”

The elder Harrod also has been seeing lots of migrating raptors in recent days. “I went kayaking on the Christina recently and spotted a northern harrier, a bald eagle and an osprey,” reports Harrod.

Make time to get out to a Hawk Watch site soon. The best time to visit is on a sunny, clear day when there is a breeze from the north or northwest, says White. If you’re lucky, you’ll see a kettle or two of broad-wingeds flying overhead.

Hawk Watch sites

Ashland Hawk Watch is located at Ashland Nature Center in Hockessin. Cape Henlopen Hawk Watch is at Cape Henlopen State Park in Lewes. For more information about either hawk watch contact Anthony Gonzon at 735-8673 or go to this website.

Article by Margo McDonough

This article can also be viewed on UDaily.

Share

UD researchers use weevils to check spread of prolific mile-a-minute weed

July 2, 2012 under CANR News

Mile-a-minute weed has declared war on Doug Tallamy’s yard. This non-native, invasive vine is growing up his trees, scrambling over shrubs and smothering tree seedlings. By blocking sunlight, it weakens a plant by reducing its ability to photosynthesize.

Mile-a-minute doesn’t care one whit that Tallamy, professor and chair of the University of Delaware’s Department of Entomology and Wildlife Ecology, is a highly respected proponent of native gardening who doesn’t believe in planting any non-natives, let alone a highly invasive non-native.

“The deer brought mile-a-minute from our neighbor’s yard three years after we moved in,” says Tallamy. “We had just a few plants the first year, a few hundred the second year, and 20 trillion the third year.”

Accidentally introduced to the U.S. from China in the 1930s, mile-a-minute doesn’t actually grow a mile per minute but it definitely is prolific. Studies show it can grow six inches per day. In addition to Tallamy’s yard, it has waged battle on countless other area yards as well as on Pea Patch Island, at White Clay Creek State Park, at Coverdale Farm Preserve and at other important natural areas.

Chemical control measures aren’t very effective and native insects don’t like to eat mile-a-minute. So Tallamy hand pulls mile-a-minute and, in areas where it has spread widely, whacks it with a scythe. But thanks to UD colleague Judy Hough-Goldstein, Tallamy has another tool in his arsenal, a weevil known as Rhinoncomimus latipes.

Weevils are beetles that have snouts. The itsy-bitsy Rhinoncomimus latipes, a native of China, is host-specific to mile-a-minute; it won’t eat any other plant. Since 2004, Hough-Goldstein and cooperators have released Rhinoncomimus latipes at numerous sites in Delaware and in Chester County, Pa., including Tallamy’s backyard.

A professor of entomology who has spearheaded a number of groundbreaking research projects into the biological control of invasive plants, Hough-Goldstein had to conduct eight years of laboratory testing in quarantine before the federal government would permit fieldwork to be carried out.

She was the first researcher in the world to obtain a permit to release a biological control agent of mile-a-minute weed. Today, her lab is still the only one in the U.S. — and one of a handful in the world — attempting to control this invasive plant through biological means.

Results, thus far, have been encouraging. The weevil establishes easily because it produces multiple generations per year. Thus, only a couple hundred weevils need to be released at any one site. Adult weevils and their larvae eat and damage mile-a-minute, but even more importantly, appear to suppress seed production in the plant.

“We had a problem with mile-a-minute at Burrows Run, which is part of Coverdale Farm Preserve,” notes Dave Pro, a land and facilities steward for the Delaware Nature Society. “We participated in UD’s early field studies with Rhinoncomimus latipes and followed up with a second weevil release. Since then, we’ve seen a reduction of mile-a-minute vine and weevils have been found actively feeding.”

In June, Hough-Goldstein kicked off a new phase of her research. The U.S. Forest Service is funding a study that compares the performance of weevils already in the field against lab-reared weevils and field weevils direct from China.

“Currently, weevils that are sent to cooperators throughout the northeastern U.S. come from a Beneficial Insect Laboratory operated by the New Jersey Department of Agriculture,” says Hough-Goldstein. “However, insects that are lab-reared for 10 or more generations adapt to lab conditions and this can sometimes affect their field performance. We’ll compare the survival, longevity and reproductive abilities of the three different populations of weevils to see if it may be desirable to add wild-type genetic material to the rearing stock.”

Amanda Stout is a rising junior at UD who is participating in the Summer Scholar research program. Throughout the summer, she will be responsible for most of the fieldwork for the new project.

To her delight, she has discovered that this means doing a bit of everything. “With Dr. Hough-Goldstein’s help, I designed and constructed rearing tubs for the weevils,” says Stout. “I also spent several days installing ‘bug dorms’ in full sun as well as in full shade.”

“I really gain intellectual satisfaction out of my work at the end of the day. It’s really exciting to get results,” she says.

As for Tallamy’s backyard, weevils are making in-roads in the ongoing war against mile-a-minute, with certain limitations.

“My assessment of the weevil is that it is quite effective in dry years,” says Tallamy. “But it doesn’t outpace mile-a-minute in wet years, such as last year when we had 12 more inches of rain than usual. However, the weevils are munching away at mile-a-minute this summer, so I’m happy to have them in my yard.”

Article by Margo McDonough

Photo by Danielle Quigley

This article can also be viewed on UDaily.

Share

CANR’s Delaney has the buzz on UD’s new research apiary

June 21, 2012 under CANR News

Debbie Delaney has two million new best friends.

That’s the number of honey bees buzzing about in the recently opened University of Delaware research apiary, which joins an existing 30-colony teaching apiary on the university’s Newark Farm.

Delaney, a UD assistant professor of entomology and wildlife ecology, has been researching honey bees for years but continues to be amazed at their abilities, ranging from the way they precisely maintain colony temperature to their figure-eight dances that tell hive mates where to find patches of flowers and water.

She has a hunch that her insect friends have some undisclosed talents, too. For example, in her own backyard beekeeping, she has noticed that hives that swarm and split into separate colonies seem to have fewer mites than hives that don’t split up.

“Varroa mites are the single biggest threat to honey bee health. Most backyard beekeepers and commercial operations treat for mites,” says Delaney. “But I think mites can be reduced naturally by interrupting their brood cycle. Mites require bee brood for reproduction but the brood cycle is interrupted when colonies are split, thus slowing mite reproduction rates. This reduces the total number of mites in each new colony.”

Delaney doesn’t treat with miticides in her personal hives; she simply allows certain colonies in the apiary to swarm and make new colonies when they are so inclined, rather than repress such efforts. Although she relies on gut instinct in her own backyard, Delaney knows she can’t advise other beekeepers until she puts her theories to rigorous test.

That’s where the new research apiary comes in. Delaney received a $50,000 grant from the Environmental Protection Agency for the facility, which is operated in collaboration with a new apiary at Penn State University. Research at both locations will focus on non-chemical ways to manage parasites in small colonies. The goal is to reduce pesticide use by small beekeepers by as much as 80 percent.

Varroa mites are only the size of a small freckle but they can wreak havoc on hives. First reported in the U.S. in 1987, varroa mites are now the major killer of all bee colonies, wild or managed.

“I don’t think splitting and swarming is sufficient to control mites in large, commercial operations but our research project may show that it’s a good management practice for small-scale beekeeping,” says Delaney.

Historically, beekeepers have tried to prevent their bees from swarming because they thought the process was detrimental to honey production and pollination. But existing research already shows that colonies allowed to swarm show lower mite numbers and decreased bee mortality. Delaney’s research may help beekeepers look at apiaries as dynamic systems that require constant turn-over to stay healthy.

“I’m trying to re-define what’s considered to be a healthy apiary,” says Delaney. “We want to reduce the use of chemicals and create sustainable, long-term solutions to the issue of mites and other pests in honey bee colonies.”

Katy Evans is a new UD graduate student who will be overseeing the research apiary. She also will be managing varroa mite research at Penn State’s apiary, with assistance from researchers there. A 2009 graduate of the University of Florida, Evans most recently worked for the state of Florida as an African honey bee lab technician.

A Florida native, she says she is excited to be part of a varroa mite project because the pest is an even greater problem in Florida than here in Delaware. “It’s hotter in Florida, and gets hotter sooner,” says Evans. “This weakens the bees and gives the varroa mites a greater opportunity to infest the hives.”

“I’m really pumped about working in a brand-new apiary and being in charge of the project,” adds Evans. “I hope that our research is able to help small beekeepers better manage their hives.”

UD’s teaching apiary had a good winter and the number of colonies is up. However, this bucks the overall trend of declining honey bee populations. Since 2007, there has been a loss of approximately 33 percent of over-wintered colonies in the U.S. each year.

“Colony declines in domestic honey bees continues to be a major concern,” says Delaney. “We still don’t know the cause or causes. But our research project may give us a better understanding of the role that natural resistance plays in fighting disease or environmental stress, as well as a better understanding of genetic components that contribute to ‘survivor stock.’”

Article by Margo McDonough

Photo by Danielle Quigley

This article can also be viewed on UDaily.

Share

UD’s McCarthy part of group that films rare striped rabbit in Sumatra

May 23, 2012 under CANR News

With cameras set up in Sumatra looking for medium- and small-sized wild cats, such as leopards, a research group involving the University of Delaware’s Kyle McCarthy, found images of something else entirely — a rabbit. Not just any ordinary rabbit, but a Sumatran striped rabbit, one of the world’s rarest species and one that had been captured on film only three times before.

There has never been a viable study of the Sumatran striped rabbit and McCarthy, assistant professor in the Department of Entomology and Wildlife Ecology in the College of Agriculture and Natural Resources (CANR), said that while his group plans on continuing their study of small cats, they are now also focusing on the rare rabbit species.

“This is the most data that anybody has compiled on these rabbits ever,” said McCarthy. “The idea would be to go get a better idea of how many there might be in an area and we’re hoping that this can spur that forward.”

For the study, led by Jennifer McCarthy, a doctoral candidate in the Department of Environmental Conservation at the University of Massachusetts Amherst, the group obtained 10 photographs of the Sumatran striped rabbit on two separate occasions in locations 790 meters apart in the Liwa region of Bukit Barisan Seletan National Park.

After obtaining the photographs, the group conducted an informal survey of colleagues who have worked in other protected areas of Sumatra to find out if they had ever seen or documented on film the Sumatran striped rabbit to get a better idea of where the rabbits might be living.

According to Kyle McCarthy, there is a great need for collaboration among the many groups studying animal species in the area because “this is one of those things that can just fly under the radar.”

With disparate researchers in different groups in many different parks, McCarthy said scientists have to collaborate or they could miss out on an important discovery.

The group found that most of the researchers hadn’t recorded the species, but they did find that scientists in Kerinci Seblat National Park, the largest park in Sumatra, had recently seen the rabbits multiple times.

One of the main factors working in the rabbits’ favor is that the group photographed them in an area that thus far has not been subject to heavy amounts of poaching. “One of the problems is that Sumatra continues to be settled and so we’re going to get more and more pressure around the edges of the parks and we’re going to see more poaching,” said McCarthy. “In other parts of this exact same park, we see a lot of poaching across the boundaries. This part is up high enough that we don’t see as many people and we don’t see as many poachers.” A point that McCarthy wanted to make clear is that most of the poachers are doing so to feed themselves, not as a means to profit.

McCarthy said that one of the reasons the group is so eager to launch a study of the rabbit is that “this could be a good spot to try and conserve them, especially for now, because they haven’t had that poaching pressure yet and so there’s probably a bigger population there.”

For now, McCarthy is just excited to be able to bring focus to a species that has been neglected for too long. “We’ve had a chance to not rediscover a species but, in essence, to bring focus back to a very rare rabbit. Often things like rabbits go overlooked because most people don’t even know there is a Sumatran rabbit. Part of doing field work in remote locations is that we are able to see things like this, and it can be really important for conservation.”

Details of the research and the team’s findings are being published in Oryx, an international wildlife journal. For a first look at the article, see the journal website.

The research was funded by the Mohamed bin Zaved Species Conservation Fund, Panthera and the McCarthy Laboratory in CANR’s Department of Entomology and Wildlife Ecology.

Article by Adam Thomas

Photo courtesy of Kyle McCarthy

This article can also be viewed on UDaily

To watch a video of the rabbit, visit the University of Delaware’s Youtube page

Share